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  • 251.
    Ahsan, Aisha
    et al.
    Univ Basel, Switzerland.
    Mousavi, S. Fatemeh
    Univ Basel, Switzerland.
    Nijs, Thomas
    Univ Basel, Switzerland.
    Nowakowska, Sylwia
    Univ Basel, Switzerland.
    Popova, Olha
    Univ Basel, Switzerland.
    Wackerlin, Aneliia
    Univ Basel, Switzerland.
    Björk, Jonas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Gade, Lutz H.
    Heidelberg Univ, Germany.
    Jung, Thomas A.
    Paul Scherrer Inst, Switzerland.
    Phase Transitions in Confinements: Controlling Solid to Fluid Transitions of Xenon Atoms in an On-Surface Network2019Ingår i: Small, ISSN 1613-6810, E-ISSN 1613-6829, Vol. 15, nr 3, artikel-id 1803169Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study reports on "phase" transitions of Xe condensates in on-surface confinements induced by temperature changes and local probe excitation. The pores of a metal-organic network occupied with 1 up to 9 Xe atoms are investigated in their propensity to undergo "condensed solid" to "confined fluid" transitions. Different transition temperatures are identified, which depend on the number of Xe atoms in the condensate and relate to the stability of the Xe clustering in the condensed "phase." This work reveals the feature-rich behavior of transitions of confined planar condensates, which provide a showcase toward future "phase-transition" storage media patterned by self-assembly. This work is also of fundamental interest as it paves the way to real space investigations of reversible solid to fluid transitions of magic cluster condensates in an array of extremely well-defined quantum confinements.

  • 252.
    Ahsan, Aisha
    et al.
    Univ Basel, Switzerland.
    Mousavi, S. Fatemeh
    Univ Basel, Switzerland.
    Nijs, Thomas
    Univ Basel, Switzerland.
    Nowakowska, Sylwia
    Univ Basel, Switzerland.
    Popova, Olha
    Univ Basel, Switzerland.
    Wackerlin, Aneliia
    Univ Basel, Switzerland.
    Björk, Jonas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Gade, Lutz H.
    Heidelberg Univ, Germany.
    Jung, Thomas A.
    Univ Basel, Switzerland; Paul Scherrer Inst, Switzerland.
    Watching nanostructure growth: kinetically controlled diffusion and condensation of Xe in a surface metal organic network2019Ingår i: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 11, nr 11, s. 4895-4903Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Diffusion, nucleation and growth provide the fundamental access to control nanostructure growth. In this study, the temperature activated diffusion of Xe at and between different compartments of an on-surface metal organic coordination network on Cu(111) has been visualized in real space. Xe atoms adsorbed at lower energy sites become mobile with increased temperature and gradually populate energetically more favourable binding sites or remain in a delocalized fluid form confined to diffusion along a topological subset of the on-surface network. These diffusion pathways can be studied individually under kinetic control via the chosen thermal energy kT of the sample and are determined by the network and sample architecture. The spatial distribution of Xe in its different modes of mobility and the time scales of the motion is revealed by Scanning Tunneling Microscopy (STM) at variable temperatures up to 40 K and subsequent cooling to 4 K. The system provides insight into the diffusion of a van der Waals gas on a complex structured surface and its nucleation and coarsening/growth into larger condensates at elevated temperature under thermodynamic conditions.

  • 253.
    Ahsan, Naveed
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Ouacha, Aziz
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Dabrowski, Jerzy
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Samuelsson, Carl
    Swedish Defence Research Agency (FOI), P.O. Box 1165, SE-581 11 Linköping, Sweden.
    Dual Band Tunable LNA for Flexible RF Front End2007Ingår i: Proceedings of the IEEE International Bhurban Conference on Applied Sciences & Technology (IBCAST 2007), January 8-11, 2007, Islamabad, Pakistan, IEEE Explore , 2007, s. 19-22Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents a dual band LNA that can be switched between two bands (2.4 GHz & 5.2 GHz) for IEEE 802.1 la/b/g WLAN applications. The LNA is also tunable within each band and the tuning is incorporated by on-chip varactors. The test chip consists of two fully integrated narrow-band tunable LNAs along with SPDT switch. For power saving one LNA can be switched off. The technology process is 0.2 mum GaAs offered by OMMIC. The LNA can achieve a relatively good performance over the two bands as demonstrated by simulation. With a 3V supply, the LNA has a gain of 26.2 dB at 2.4 GHz and 21.8 dB at 5.2 GHz and the corresponding NF varies between 2.07 dB and 1.84 dB, respectively. The LNA has an IIP3 of -7 dBm at 2.4 GHz and -1.6 dBm at 5.2 GHz.

  • 254.
    Ahsan, Naveed
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Ouacha, Aziz
    Linköpings universitet, Institutionen för systemteknik, Elektroniska komponenter. Linköpings universitet, Tekniska högskolan.
    Samuelsson, Carl
    Swedish Defence Research Agency (FOI), P.O. Box 1165, SE-581 11 Linköping, Sweden.
    Boman, Tomas
    Swedish Defence Research Agency (FOI), P.O. Box 1165, SE-581 11 Linköping, Sweden.
    Applications of Programmable Microwave Function Array (PROMFA)2007Ingår i: Proceedings of the IEEE European Conference on Circuit Theory and Design (ECCTD 2007), August 26-30, 2007, Seville, Spain, IEEE , 2007, s. 164 -167Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper describes the use of programmable microwave function array (PROMFA) for different microwave application. The PROMFA concept is based on an array of generic cells, in which a number of different functions can be realized. Each PROMFA cell is a four-port circuit, that can either be programmed independently or collectively according to a specific need. Specifically, the phase shift capability in a single PROMFA cell, useful for a new type of phase shifter design is discussed. The paper also presents the functionality of this new architecture as a beamforming network. As an example case an active corporate feed network and a tunable recursive filter is demonstrated. Simulated and measured results are presented.

  • 255.
    Ahvenniemi, Esko
    et al.
    Aalto University, Finland.
    Akbashev, Andrew R.
    Stanford University, CA 94305 USA.
    Ali, Saima
    Aalto University, Finland.
    Bechelany, Mikhael
    University of Montpellier, France.
    Berdova, Maria
    University of Twente, Netherlands.
    Boyadjiev, Stefan
    Bulgarian Academic Science, Bulgaria.
    Cameron, David C.
    Masaryk University, Czech Republic.
    Chen, Rong
    Huazhong University of Science and Technology, Peoples R China.
    Chubarov, Mikhail
    University of Grenoble Alpes, France.
    Cremers, Veronique
    University of Ghent, Belgium.
    Devi, Anjana
    Ruhr University of Bochum, Germany.
    Drozd, Viktor
    St Petersburg State University, Russia.
    Elnikova, Liliya
    Institute Theoret and Expt Phys, Russia.
    Gottardi, Gloria
    Fdn Bruno Kessler, Italy.
    Grigoras, Kestutis
    VTT Technical Research Centre Finland, Finland.
    Hausmann, Dennis M.
    Lam Research Corp, OR 97062 USA.
    Seong Hwang, Cheol
    Seoul National University, South Korea; Seoul National University, South Korea.
    Jen, Shih-Hui
    Globalfoundries, NY 12203 USA.
    Kallio, Tanja
    Aalto University, Finland.
    Kanervo, Jaana
    Aalto University, Finland; Abo Akad University, Finland.
    Khmelnitskiy, Ivan
    St Petersburg Electrotech University of LETI, Russia.
    Han Kim, Do
    MIT, MA 02139 USA.
    Klibanov, Lev
    Techinsights, Canada.
    Koshtyal, Yury
    Ioffe Institute, Russia.
    Krause, A. Outi I.
    Aalto University, Finland.
    Kuhs, Jakob
    University of Ghent, Belgium.
    Kaerkkaenen, Irina
    Sentech Instruments GmbH, Germany.
    Kaariainen, Marja-Leena
    NovaldMedical Ltd Oy, Finland.
    Kaariainen, Tommi
    NovaldMedical Ltd Oy, Finland; University of Helsinki, Finland.
    Lamagna, Luca
    STMicroelectronics, Italy.
    Lapicki, Adam A.
    Seagate Technology Ireland, North Ireland.
    Leskela, Markku
    University of Helsinki, Finland.
    Lipsanen, Harri
    Aalto University, Finland.
    Lyytinen, Jussi
    Aalto University, Finland.
    Malkov, Anatoly
    Technical University, Russia.
    Malygin, Anatoly
    Technical University, Russia.
    Mennad, Abdelkader
    CDER, Algeria.
    Militzer, Christian
    Technical University of Chemnitz, Germany.
    Molarius, Jyrki
    Summa Semicond Oy, Finland.
    Norek, Malgorzata
    Mil University of Technology, Poland.
    Ozgit-Akgun, Cagla
    ASELSAN Inc, Turkey.
    Panov, Mikhail
    St Petersburg Electrotech University of LETI, Russia.
    Pedersen, Henrik
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska fakulteten.
    Piallat, Fabien
    KOBUS, France.
    Popov, Georgi
    University of Helsinki, Finland.
    Puurunen, Riikka L.
    VTT Technical Research Centre Finland, Finland.
    Rampelberg, Geert
    University of Ghent, Belgium.
    Ras, Robin H. A.
    Aalto University, Espoo, Finland.
    Rauwel, Erwan
    Tallinn University of Technology, Estonia.
    Roozeboom, Fred
    Eindhoven University of Technology, Netherlands; TNO, Netherlands.
    Sajavaara, Timo
    University of Jyvaskyla, Finland.
    Salami, Hossein
    University of Maryland, MD 20742 USA.
    Savin, Hele
    Aalto University, Finland.
    Schneider, Nathanaelle
    IRDEP CNRS, France; IPVF, France.
    Seidel, Thomas E.
    Seitek50, FL 32135 USA.
    Sundqvist, Jonas
    Fraunhofer Institute Ceram Technology and Syst IKTS, Germany.
    Suyatin, Dmitry B.
    Lund University, Sweden; Lund University, Sweden.
    Torndahl, Tobias
    Uppsala University, Sweden.
    van Ommen, J. Ruud
    Delft University of Technology, Netherlands.
    Wiemer, Claudia
    CNR, Italy.
    Ylivaara, Oili M. E.
    VTT Technical Research Centre Finland, Finland.
    Yurkevich, Oksana
    Immanuel Kant Balt Federal University, Russia.
    Recommended reading list of early publications on atomic layer deposition-Outcome of the "Virtual Project on the History of ALD"2017Ingår i: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 35, nr 1, artikel-id 010801Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Atomic layer deposition (ALD), a gas-phase thin film deposition technique based on repeated, self-terminating gas-solid reactions, has become the method of choice in semiconductor manufacturing and many other technological areas for depositing thin conformal inorganic material layers for various applications. ALD has been discovered and developed independently, at least twice, under different names: atomic layer epitaxy (ALE) and molecular layering. ALE, dating back to 1974 in Finland, has been commonly known as the origin of ALD, while work done since the 1960s in the Soviet Union under the name "molecular layering" (and sometimes other names) has remained much less known. The virtual project on the history of ALD (VPHA) is a volunteer-based effort with open participation, set up to make the early days of ALD more transparent. In VPHA, started in July 2013, the target is to list, read and comment on all early ALD academic and patent literature up to 1986. VPHA has resulted in two essays and several presentations at international conferences. This paper, based on a poster presentation at the 16th International Conference on Atomic Layer Deposition in Dublin, Ireland, 2016, presents a recommended reading list of early ALD publications, created collectively by the VPHA participants through voting. The list contains 22 publications from Finland, Japan, Soviet Union, United Kingdom, and United States. Up to now, a balanced overview regarding the early history of ALD has been missing; the current list is an attempt to remedy this deficiency. (C) 2016 Author(s).

  • 256. Aichholzer, Oswin
    et al.
    Akitaya, Hugo
    Cheung, Kenny
    Demaine, Erik
    Demaine, Martin
    Fekete, Sándor
    Kleist, Linda
    Kostitsyna, Irina
    Löffler, Maarten
    Masárová, Zuzana
    Mundilova, Klara
    Schmidt, Christiane
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Folding Polyominoes with Holes into a Cube2019Konferensbidrag (Refereegranskat)
  • 257. Aichholzer, Oswin
    et al.
    Biro, Michael
    Demaine, Erik
    Demaine, Martin
    Eppstein, David
    Fekete, Sándor P.
    Hesterberg, Adam
    Kostitsyna, Irina
    Schmidt, Christiane
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Folding Polyominoes into (Poly)CubesIngår i: International journal of computational geometry and applications, ISSN 0218-1959Artikel i tidskrift (Refereegranskat)
  • 258.
    Aid, Graham
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell miljöteknik. Linköpings universitet, Tekniska fakulteten.
    Operationalizing Industrial Ecology in the Waste Sector: Roles and tactics for circular value innovation2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The take-make-waste approach to resource management in human production and consumption systems is contributing to a variety of environmental and social problems worldwide. Additionally, as the world’s population and affluence increase, so do the negative impacts of poor resource management. Lifting the waste management (WM) sector into a new phase of development, which takes its lead from the ideals of Industrial Ecology and circular economy, is seen by many scholars and practitioners as one potential to assist in alleviating these impacts. While there are many studies on how more efficient inter-organizational resource management is (or could be) constructed, there are relatively few business development studies which have explored novel approaches (from roles to tactics) that WM organizations might operationalize toward more efficient resource management.

    The aim of this thesis is to contribute to the development of knowledge and understanding of how the waste management sector can operationalize more effective and efficient resource management. In approaching this aim, two research questions guided the exploration of: 1) novel roles for WM and 2) support tactics for such roles. Grounded in the broader context of Industrial Ecology (IE) and Business Development, five studies were performed. Two studies, focused on the novel roles of inter-organizational resource management and high value secondary resource extraction, were performed through literature review and interviews, and market driver analysis respectively. In exploring support tactics, two design and proof of concept studies were carried out to investigate data analysis tools for inter-organizational resource management, and one long-term action research engagement project was coordinated to study hands-on inter-organizational collaboration tactics.

    The studies highlighted that the Swedish WM sector holds some key capacities for operationalizing (and in some cases, is already developing) the novel resource management roles identified: industrial symbiosis facilitator, eco-industrial park manager, holistic facility management, and high value resource extractor. However, depending on the portfolio of services to be performed in such roles, several capacities may need to be developed or strengthened. Main opportunities seen for these roles were – staying ahead of market developments, and aligning activities with organizational goals. The main general risk related to these roles was insufficient returns on investment. Looking forward, the main enablers identified were policy leadership for more balanced market mechanisms, increasing use of external knowledge, developing long term partnerships, lobbying, stockpiling resources, and carefully crafting new business models.

    The tools developed for strategically applying external information toward the identification of opportunities within new roles showed tactical potential. However, their implementation in broader development processes has yet to be fully validated. The hands-on exploration of change oriented collaboration, highlighted collective system framing and goal setting and face-to-face interaction as key activities for inter-organizational approaches within roles such as industrial symbiosis facilitator.

    Throughout the studies, several novel roles were investigated. Each of these roles will need to be individually evaluated by directing bodies of WM organizations, and evaluated from the organization’s vision and strategy. If certain roles are chosen to be explored in more detail, they will need to be developed within full business models - addressing issues such as income structure, internal processes and capacities to be developed, and key customers. Through applying IE and business development concepts and findings, WM organizations have possibilities to translate ambitious visions into novel offerings.

    Delarbeten
    1. Expanding roles for the Swedish waste management sector in interorganizational resource management
    Öppna denna publikation i ny flik eller fönster >>Expanding roles for the Swedish waste management sector in interorganizational resource management
    2017 (Engelska)Ingår i: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 124, s. 85-97Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Several waste management (WM) professionals see an ongoing shift in the focus of the industry, from that of atransport and treatment sector to that of a more integrated sustainable service provision and material productionsector. To further develop such transitional ambitions, WM organizations are increasingly looking toward interorganizationalresource network concepts (such as the circular economy and industrial symbiosis) as models ofhow they would like to create new value together with their customers and partners.This article aims to take a step in addressing uncertainties behind such transitions by analyzing barriers forinter-organizational resource management and in turn uncovering some potential opportunities and risks ofnovel offerings from the WM sector. Obstacles for developing innovative inter-organizational resource networkshave been identified based on studies of implementing industrial symbiosis networks. Subsequently, managingexecutives from Swedish private and public WM organizations were interviewed regarding the sector’s capacityto overcome such barriers – opportunities and risks of providing new resource management services – and howtheir organizations might approach the role of actively facilitating more resource efficient regions.Eco-Industrial park management and contracting out holistic resource management are some areas in whichthe respondents see WM organizations offering new services. In relation to such approaches, various risks (e.g.being cut out of investment benefits, or unstable supply) and opportunities (e.g. new markets and enhancedsustainability profiles) were identified. Additionally, it was seen that WM companies would need to makesubstantial changes to their business approach, becoming less dependent on flows of mixed materials forexample, if they are to become even more central value chain actors. To strengthen such approaches, it was seenthat the sector will need to find methods to strategically build strong, long term partnerships, expand upon andtake advantage of available knowledge resources (i.e. best practice technologies and regional material flows),and explore new business models (i.e. stockpiling, park management, or waste minimization). Additionally,working with sector representatives to argue for a more balanced market conditions next to primary productionshould assist the viability of new offerings in the wider market.

    Nyckelord
    Circular economy, Industrial symbiosis, Recycling, Business development, Green innovation
    Nationell ämneskategori
    Miljöledning
    Identifikatorer
    urn:nbn:se:liu:diva-137456 (URN)10.1016/j.resconrec.2017.04.007 (DOI)000403860200009 ()
    Anmärkning

    Funding agencies: Ragnar Sellbergs Foundation

    Tillgänglig från: 2017-05-16 Skapad: 2017-05-16 Senast uppdaterad: 2017-08-07
    2. Driving Forces and Inhibitors of Secondary Stock Extraction
    Öppna denna publikation i ny flik eller fönster >>Driving Forces and Inhibitors of Secondary Stock Extraction
    2016 (Engelska)Ingår i: The Open Waste Management Journal, ISSN 1876-4002, E-ISSN 1876-4002, Vol. 9, s. 11-18Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Even though it’s well known that our common resources are limited and that recycling is key for a sustainable future; inreality we see few examples of true recycling where virgin raw material is substituted by waste. There are endless numbers ofexamples where waste is utilized to some extent without solving the core issue: reducing the need of extracting virgin raw materials.This article analyses some of the driving forces and inhibitors of secondary stock extraction to explore why it’s so difficult establishlarge scale secondary stock extraction although suitable technologies are available. The authors discuss and suggest possible ways forreducing some of the main barriers presented.

    Nyckelord
    Circular economy, Economy, Recycling, Resources, Sustainability
    Nationell ämneskategori
    Miljöledning
    Identifikatorer
    urn:nbn:se:liu:diva-137459 (URN)10.2174/1876400201609010011 (DOI)
    Tillgänglig från: 2017-05-16 Skapad: 2017-05-16 Senast uppdaterad: 2017-11-29
    3. Looplocal - a heuristic visualization tool to support the strategic facilitation of industrial symbiosis
    Öppna denna publikation i ny flik eller fönster >>Looplocal - a heuristic visualization tool to support the strategic facilitation of industrial symbiosis
    2015 (Engelska)Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 98, s. 328-335Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Industrial symbiosis (IS) developments have been differentiated as self-organized, facilitated, and planned. This article introduces a tool, Looplocal, which has been built with objectives to support the strategic facilitation of IS. Looplocal is a visualization tool built to assist in 1) Simplifying the identification of regions susceptible to new industrial symbiosis facilitation activities 2) Enabling proactive and targeted marketing of potential exchanges to key actors in specific regions and 3) Assisting facilitators to assess the various strategies and consequential engagement and analysis methodologies suitable for additional IS development in specific regions. The tool compares industrial symbiosis data and estimated regional material and energy flows (on a facility level) to identify potential IS transfer information along with key stakeholder and network data. The authors have performed a proof of concept run of this tool on Sweden. In its early stages of application the method has given results seen as useful for identifying regions susceptible to the investment of symbiosis facilitators' time and resources. The material focus and customization possibilities for the tool show potential for a spectrum of potential facilitators: from waste management companies to national or regional authorities. In conjunction with long term business models, such a tool might be utilized throughout an adaptive chain of facilitation activities and aims.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2015
    Nationell ämneskategori
    Samhällsbyggnadsteknik
    Identifikatorer
    urn:nbn:se:liu:diva-137462 (URN)10.1016/j.jclepro.2014.08.012 (DOI)000356194300033 ()2-s2.0-84929966422 (Scopus ID)
    Anmärkning

    QC 20150713

    Tillgänglig från: 2015-07-13 Skapad: 2017-05-16 Senast uppdaterad: 2017-05-16Bibliografiskt granskad
    4. Secondary Resources in the Bio-Based Economy: A Computer Assisted Survey of Value Pathways in Academic Literature
    Öppna denna publikation i ny flik eller fönster >>Secondary Resources in the Bio-Based Economy: A Computer Assisted Survey of Value Pathways in Academic Literature
    2017 (Engelska)Ingår i: Waste and Biomass Valorization, ISSN 1877-2641, E-ISSN 1877-265X, Vol. 8, nr 7, s. 2229-2246Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Research on value pathways for organic wastes has been steadily increasing in recent decades. There have been few considerably broad overview studies of such materials and their valuation potential in the bio-based economy in part because of the vast multitude of materials and processes that can be used to produce energy carriers, chemicals, and materials of value. This article explores how automated data analysis approaches can help in analyzing large bodies of text to distill and present potential value pathways for secondary (waste) bio-based materials. The study employed multiple methods (literature collection, topic modelling, and co-occurrence analysis) on a collection of abstracts from 53,292 academic articles covering technologies, applications, and products (TAPs) for bio-based wastes. The results of both the topic modelling and co-occurrence analysis are presented as online interactive web pages. The topic modelling presented an overview of research clusters related to secondary organic resources, processes, and disciplines. The co-occurrence analysis helped to understand which TAPs are researched in relation to a broad spectrum of organic wastes. Co-occurrences were evaluated using the Normalized Pointwise Mutual Information measure to locate terms which co-occur more frequently than would be expected by chance. Through the use of detailed lists of organic wastes and TAPs, the co-occurrence method mapped out 7118 unique intersections between 473 specific wastes and 228 TAPs. This technique enables us to find seemingly non-obvious valorization pathways such as the re-use of oyster shells as catalysts for bio-diesel production and bioplastic production from brewery waste. While a proof-of-concept, this work points the way for using Big Data to suggest novel pathways for implementing the Circular Economy.

    Ort, förlag, år, upplaga, sidor
    Springer, 2017
    Nyckelord
    By-product, Waste valorization, Circular economy, Recycling, Industrial symbiosis, Big Data
    Nationell ämneskategori
    Miljövetenskap Miljöbioteknik
    Identifikatorer
    urn:nbn:se:liu:diva-138067 (URN)10.1007/s12649-017-9975-0 (DOI)000411975600001 ()2-s2.0-85020108904 (Scopus ID)
    Anmärkning

    Funding agencies: Ragnar Sellbergs Foundation

    Tillgänglig från: 2017-06-08 Skapad: 2017-06-08 Senast uppdaterad: 2017-10-23Bibliografiskt granskad
    5. Improvement of aggregate cycles in Stockholm and the Baltic Region: Activities and results of the BRA initiative
    Öppna denna publikation i ny flik eller fönster >>Improvement of aggregate cycles in Stockholm and the Baltic Region: Activities and results of the BRA initiative
    2012 (Engelska)Ingår i: Proceedings of the 8th International conference on Sustainable management of waste and recycled materials in construction, Gothenburg, Sweden, 30 May - 1 June 2012 / [ed] M. Arm, C. Vandecasteele, J. Heynen, P. Suer and B. Lind, Swedish Geotechnical Institute , 2012, s. 1-9Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    From 2009 until 2011 project BRA (Bygg-och Rivningsavfall i Stockholms Län) “Construction and Demolition (C&D) waste in Stockholm County” was coordinated from the division of Industrial Ecology, KTH. This project was focused on actively improving (from plural perspectives) the cycles of C&D (specifically non-metallic inert) materials in the region. In response to the normative aim and inter-systems complexity, a highly participative action research procedure was adopted. Through processes of network communication, workshops, a course, and an international symposium - a number of issues (such as market development, recycled product quality, greenhouse gas impacts, collaborative planning, and statistics) were prioritized, researched, and acted upon. Indicators for measuring progress in selected areas were developed and preliminary action plans created. At a final co-organized symposium Swedish delegates laid the groundwork for the establishment of a Swedish C&D recycling b ranch organization. This initiative of continued collaboration between and within sectors is seen as a vehicle for the priorities and action requirements identified in BRA to be further enabled and held in focus. Furthermore, these actors taking ownership of the process is seen as a success in accordance to the original aims and the need for further cycles of evaluation, planning, and action.

    Ort, förlag, år, upplaga, sidor
    Swedish Geotechnical Institute, 2012
    Nyckelord
    by-product, recycling, synergy, industrial ecology, facilitation
    Nationell ämneskategori
    Byggproduktion
    Identifikatorer
    urn:nbn:se:liu:diva-137463 (URN)
    Konferens
    WASCON 2012 – towards effective, durable and sustainable production and use of alternative materials in construction. 8th International conference on sustainable management of waste and recycled materials in construction, Gothenburg, Sweden, 30 May - 1 June 2012
    Anmärkning

    QC 20130522

    Tillgänglig från: 2013-05-20 Skapad: 2017-05-16 Senast uppdaterad: 2017-05-16Bibliografiskt granskad
  • 259.
    Aiempanakit, Montri
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Reactive High Power Impulse Magnetron Sputtering of Metal Oxides2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The work presented in this thesis deals with reactive magnetron sputtering processes of metal oxides with a prime focus on high power impulse magnetron sputtering (HiPIMS). The aim of the research is to contribute towards understanding of the fundamental mechanisms governing a reactive HiPIMS process and to investigate their implications on the film growth.

    The stabilization of the HiPIMS process at the transition zone between the metal and compound modes of Al-O and Ce-O was investigated for realizing the film deposition with improved properties and higher depositionrate and the results are compared with direct current magnetron sputtering (DCMS) processes. The investigations were made for different sputtering conditions obtained by varying pulse frequency, peak power and pumping speed. For the experimental conditions employed, it was found that reactive HiPIMS can eliminate/suppress the hysteresis effect for a range of frequency, leading to a stable deposition process with a high deposition rate. The hysteresis was found to be eliminated for Al-O while for Ce-O, it was not eliminated but suppressed as compared to the DCMS. The behavior of elimination/suppression of the hysteresis may be influenced by high erosion rate during the pulse, limited target oxidation between the pulses and gas rarefaction effects in front of the target. Similar investigations were made for Ti-O employing a larger target and the hysteresis was found to be suppressed as compared to the respective DCMS, but not eliminated. It was shown that the effect of gas rarefaction is a powerful mechanism for preventing oxide formation upon the target surface. The impact of this effect depends on the off-time between the pulses. Longer off-times reduce the influence of gas rarefaction.

    To gain a better understanding of the discharge current-voltage behavior in a reactive HiPIMS process of metal oxides, the ion compositions and ion energy distributions were measured for Al-O and Ti-O using time averaged and time-resolved mass spectrometry. It was shown that the different discharge current behavior between non-reactive and reactive modes couldn’t be explained solely by the change in the secondary electron emission yield from the sputtering target. The high fluxes of O1+ ions contribute substantially to the discharge current giving rise to an increase in the discharge current in the oxide mode as compared to the metal mode. The results also show that the source of oxygen in the discharge is both, the target surface (via sputtering) as well as the gas phase.

    The investigations on the properties of HiPIMS grown films were made by synthesizing metal oxide thin films using Al-O, Ti-O and Ag-Cu-O. It was shown that Al2O3 films grown under optimum condition using reactive HiPIMS exhibit superior properties as compared to DCMS. The HiPIMS grown films exhibit higher refractive index as well as the deposition rate of the film growth was higher under the same operating conditions. The effect of HiPIMS peak power on TiO2 film properties was investigated and the results are compared with the DCMS. The properties of TiO2 films such as refractive index, film density and phase structure were experimentally determined. The ion composition during film growth was investigated and an explanation on the correlation of the film properties and ion energy was made. It was found that energetic and ionized sputtered flux in reactive HiPIMS can be used to tailor the phase formation of the TiO2 films with high peak powers facilitating the rutile phase while the anatase phase can be obtained using low peak powers. These phases can be obtained at room temperature without external substrate heating or post-deposition annealing which is in contrast to the reactive DCMS where both, anatase and rutile phases of TiO2 are obtained at either elevated growth temperatures or by employing post deposition annealing. The effect of HiPIMS peak power on the crystal structure of the grown films was also investigated for ternary compound, Ag-Cu-O, for which films were synthesized using reactive HiPIMS as well as reactive DCMS. It was found that the stoichiometric Ag2Cu2O3 can be synthesized by all examined pulsing peak powers. The oxygen gas flow rate required to form stoichiometric films is proportional to the pulsing peak power in HiPIMS. DCMS required low oxygen gas flow to synthesis the stoichiometric films. The HiPIMS grown films exhibit more pronounced crystalline structure as compared to the films grown using DCMS. This is likely an effect of highly ionized depositing flux which facilitates an intense ion bombardment during the film growth using HiPIMS. Our results indicate that Ag2Cu2O3film formation is very sensitive to the ion bombardment on the substrate as well as to the backattraction of metal and oxygen ions to the target.

    Delarbeten
    1. Hysteresis and process stability in reactive high power impulse magnetron sputtering of metal oxides
    Öppna denna publikation i ny flik eller fönster >>Hysteresis and process stability in reactive high power impulse magnetron sputtering of metal oxides
    Visa övriga...
    2011 (Engelska)Ingår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 519, nr 22, s. 7779-7784Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In the further development of reactive sputter deposition, strategies which allow for stabilization of the transition zone between the metallic and compound modes, elimination of the process hysteresis, and increase of the deposition rate, are of particular interest. In this study, the hysteresis behavior and the characteristics of the transition zone during reactive high power impulse magnetron sputtering (HiPIMS) of Al and Ce targets in an Ar-O(2) atmosphere as a function of the pulsing frequency and the pumping speed are investigated. Comparison with reactive direct current magnetron sputtering (DCMS) reveals that HiPIMS allows for elimination/suppression of the hysteresis and a smoother transition from the metallic to the compound sputtering mode. For the experimental conditions employed in the present study, optimum behavior with respect to the hysteresis width is obtained at frequency values between 2 and 4 kHz, while HiPIMS processes with values below or above this range resemble the DCMS behavior. Al-O films are deposited using both HiPIMS and DCMS. Analysis of the film properties shows that elimination/suppression of the hysteresis in HiPIMS facilitates the growth of stoichiometric and transparent Al(2)O(3) at relatively high deposition rates over a wider range of experimental conditions as compared to DCMS.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2011
    Nyckelord
    Reactive sputtering, High power impulse magnetron sputtering, Aluminum oxide, Cerium oxide, Hysteresis, Process stability
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-71797 (URN)10.1016/j.tsf.2011.06.021 (DOI)000295057000027 ()
    Anmärkning

    Funding Agencies|Swedish Research Council (VR)|621-2008-3222|Strategic Research Center in Materials Science for Nanoscale Surface Engineering (MS2E)||Ministry of Science and Technology, Thailand||VR|623-2009-7348|

    Tillgänglig från: 2011-11-04 Skapad: 2011-11-04 Senast uppdaterad: 2017-12-08
    2. Studies of hysteresis effect in reactive HiPIMS deposition of oxides
    Öppna denna publikation i ny flik eller fönster >>Studies of hysteresis effect in reactive HiPIMS deposition of oxides
    Visa övriga...
    2011 (Engelska)Ingår i: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 205, s. S303-S306Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    igh power impulse magnetron sputtering (HiPIMS) has proven to be capable of substantial improvement of the quality of deposited coatings. Lately, there have been a number of reports indicating that the hysteresis effect may be reduced in HiPIMS mode resulting in an increase of the deposition rate of stoichiometric compound as compared to a direct current magnetron sputtering process in oxide mode. In this contribution, we have studied the hysteresis behaviour of Ti metal targets sputtered in Ar + O(2) mixtures. For fixed pulse on time and a constant average power, there is an optimum frequency minimizing the hysteresis. The effect of gas dynamics was analyzed by measurements of the gas refill time and rarefaction. Results indicate that the gas rarefaction may be responsible for the observed hysteresis behaviour. The results are in agreement with a previous study of Al oxide reactive process.

    Ort, förlag, år, upplaga, sidor
    Elsevier Science B.V., Amsterdam., 2011
    Nyckelord
    Magnetron sputtering, Reactive sputtering, HiPIMS, Hysteresis, Oxides deposition
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-69986 (URN)10.1016/j.surfcoat.2011.01.019 (DOI)000293258600065 ()
    Tillgänglig från: 2011-08-12 Skapad: 2011-08-12 Senast uppdaterad: 2017-12-08
    3. Understanding the discharge current behavior in reactive high power impulse magnetron sputtering of oxides
    Öppna denna publikation i ny flik eller fönster >>Understanding the discharge current behavior in reactive high power impulse magnetron sputtering of oxides
    Visa övriga...
    2013 (Engelska)Ingår i: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 113, nr 13Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The discharge current behavior in reactive high power impulse magnetron sputtering (HiPIMS) of Ti-O and Al-O is investigated. It is found that for both metals, the discharge peak current significantly increases in the oxide mode in contrast to the behavior in reactive direct current magnetron sputtering where the discharge current increases for Al but decreases for Ti when oxygen is introduced. In order to investigate the increase in the discharge current in HiPIMS-mode, the ionic contribution of the discharge in the oxide and metal mode is measured using time-resolved mass spectrometry. The energy distributions and time evolution are investigated during the pulse-on time as well as in the post-discharge. In the oxide mode, the discharge is dominated by ionized oxygen, which has been preferentially sputtered from the target surface. The ionized oxygen determines the discharge behavior in reactive HiPIMS.

    Ort, förlag, år, upplaga, sidor
    American Institute of Physics (AIP), 2013
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-91256 (URN)10.1063/1.4799199 (DOI)000317238000006 ()
    Tillgänglig från: 2013-04-18 Skapad: 2013-04-18 Senast uppdaterad: 2017-12-06
    4. Effect of peak power in reactive high power impulse magnetron sputtering of titanium dioxide
    Öppna denna publikation i ny flik eller fönster >>Effect of peak power in reactive high power impulse magnetron sputtering of titanium dioxide
    Visa övriga...
    2011 (Engelska)Ingår i: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 205, nr 20, s. 4828-4831Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The effect of peak power in a high power impulse magnetron sputtering (HiPIMS) reactive deposition of TiO(2) films has been studied with respect to the deposition rate and coating properties. With increasing peak power not only the ionization of the sputtered material increases but also their energy. In order to correlate the variation in the ion energy distributions with the film properties, the phase composition, density and optical properties of the films grown with different HiPIMS-parameters have been investigated and compared to a film grown using direct current magnetron sputtering (DCMS). All experiments were performed for constant average power and pulse on time (100W and 35 mu s, respectively), different peak powers were achieved by varying the frequency of pulsing. Ion energy distributions for Ti and O and its dependence on the process conditions have been studied. It was found that films with the highest density and highest refractive index were grown under moderate HiPIMS conditions (moderate peak powers) resulting in only a small loss in mass-deposition rate compared to DCMS. It was further found that TiO2 films with anatase and rutile phases can be grown at room temperature without substrate heating and without post-deposition annealing.

    Ort, förlag, år, upplaga, sidor
    Elsevier Science B.V., Amsterdam., 2011
    Nyckelord
    HiPIMS; Titanium dioxide; Rutile; Anatase; Reactive sputtering; TiO(2)
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-69795 (URN)10.1016/j.surfcoat.2011.04.071 (DOI)000292361400013 ()
    Anmärkning

    Original Publication: Montri Aiempanakit, Ulf Helmersson, Asim Aijaz, Petter Larsson, Roger Magnusson, Jens Jensen and Tomas Kubart, Effect of peak power in reactive high power impulse magnetron sputtering of titanium dioxide, 2011, Surface & Coatings Technology, (205), 20, 4828-4831. http://dx.doi.org/10.1016/j.surfcoat.2011.04.071 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/

    Tillgänglig från: 2011-08-10 Skapad: 2011-08-08 Senast uppdaterad: 2017-12-08
    5. Ag2Cu2O3 thin films deposited by reactive high power impulse magnetron sputtering
    Öppna denna publikation i ny flik eller fönster >>Ag2Cu2O3 thin films deposited by reactive high power impulse magnetron sputtering
    2013 (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Ag2Cu2O3 thin films were prepared by reactive high power impulse magnetron sputtering (HiPIMS) from an alloy silver-copper (Ag0.5Cu0.5) target on silicon and glass substrates. The effects of the oxygen gas flow and the peak power on the structural properties of the films were investigated. Structural characterization by grazing incidence X-ray diffraction measurements show that the structure of Ag2Cu2O3 is related to the oxygen flow and the peak power. Films grown with high peak power required higher oxygen flow rate in order to get stoichiometric Ag2Cu2O3 thin films. It was further found that using HiPIMS, polycrystalline Ag2Cu2O3 films can be grown at room temperature without substrate heating or post-deposition annealing, while films deposited by DCMS exhibit poor crystallinity under the same process conditions.

    Nyckelord
    Silver-copper oxide, HiPIMS, Reactive sputtering, film structure
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-91258 (URN)
    Tillgänglig från: 2013-04-18 Skapad: 2013-04-18 Senast uppdaterad: 2013-10-30Bibliografiskt granskad
  • 260.
    Aiempanakit, Montri
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Aijaz, Asim
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Lundin, Daniel
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Helmersson, Ulf
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Kubart, Tomas
    The Ångström Laboratory, Uppsala University, Uppsala, Sweden.
    Understanding the discharge current behavior in reactive high power impulse magnetron sputtering of oxides2013Ingår i: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 113, nr 13Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The discharge current behavior in reactive high power impulse magnetron sputtering (HiPIMS) of Ti-O and Al-O is investigated. It is found that for both metals, the discharge peak current significantly increases in the oxide mode in contrast to the behavior in reactive direct current magnetron sputtering where the discharge current increases for Al but decreases for Ti when oxygen is introduced. In order to investigate the increase in the discharge current in HiPIMS-mode, the ionic contribution of the discharge in the oxide and metal mode is measured using time-resolved mass spectrometry. The energy distributions and time evolution are investigated during the pulse-on time as well as in the post-discharge. In the oxide mode, the discharge is dominated by ionized oxygen, which has been preferentially sputtered from the target surface. The ionized oxygen determines the discharge behavior in reactive HiPIMS.

  • 261.
    Aiempanakit, Montri
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Lund, Esben
    Department of Physics/Center for Materials Science and Nanotechnology, University of Oslo, Oslo, Norway.
    Kubart, Tomas
    The Ångström Laboratory, Uppsala University, Uppsala, Sweden.
    Helmersson, Ulf
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Ag2Cu2O3 thin films deposited by reactive high power impulse magnetron sputtering2013Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Ag2Cu2O3 thin films were prepared by reactive high power impulse magnetron sputtering (HiPIMS) from an alloy silver-copper (Ag0.5Cu0.5) target on silicon and glass substrates. The effects of the oxygen gas flow and the peak power on the structural properties of the films were investigated. Structural characterization by grazing incidence X-ray diffraction measurements show that the structure of Ag2Cu2O3 is related to the oxygen flow and the peak power. Films grown with high peak power required higher oxygen flow rate in order to get stoichiometric Ag2Cu2O3 thin films. It was further found that using HiPIMS, polycrystalline Ag2Cu2O3 films can be grown at room temperature without substrate heating or post-deposition annealing, while films deposited by DCMS exhibit poor crystallinity under the same process conditions.

  • 262.
    Aiempanakit, Montri
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik.
    Lundin, Daniel
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik.
    Larsson, Petter
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik.
    Jädernäs, Daniel
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik.
    Helmersson, Ulf
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik.
    Effects on deposition rate when varying the magnetic field strength in magnetron sputtering2008Ingår i: 14th International Congress on Thin Films,2008, 2008Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Poster

  • 263. Aifa, Sami
    et al.
    Frikha, Fakher
    Miled, Nabil
    Johansen, Knut
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad Fysik.
    Lundström, Ingemar
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad Fysik.
    Svensson, Samuel P.S.
    Astra Zeneca.
    Phosphorylation of Thr654 but not Thr669 within the juxtamembrane domain of the EGF receptor inhibits calmodulin binding2006Ingår i: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 347, nr 2, s. 381-387Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Calcium-calmodulin (CaM) binding to the epidermal growth factor receptor (EGFR) has been shown to both inhibit and stimulate receptor activity. CaM binds to the intracellular juxtamembrane (JM) domain (Met645-Phe688) of EGFR. Protein kinase C (PKC) mediated phosphorylation of Thr654 occurs within this domain. CaM binding to the JM domain inhibits PKC phosphorylation and conversely PKC mediated phosphorylation of Thr654 or Glu substitution of Thr654 inhibits CaM binding. A second threonine residue (Thr669) within the JM domain is phosphorylated by the mitogen-activated protein kinase (MAPK). Previous results have shown that CaM interferes with EGFR-induced MAPK activation. If and how phosphorylation of Thr669 affects CaM-EGFR interaction is however not known.In the present study we have used surface plasmon resonance (BIAcore) to study the influence of Thr669 phosphorylation on real time interactions between the intracellular juxtamembrane (JM) domain of EGFR and CaM. The EGFR-JM was expressed as GST fusion proteins in Escherichia coli and phosphorylation was mimicked by generating Glu substitutions of either Thr654 or Thr669. Purified proteins were coupled to immobilized anti-GST antibodies at the sensor surface and increasing concentration of CaM was applied. When mutating Thr654 to Glu654 no specific CaM binding could be detected. However, neither single substitutions of Thr669 (Gly669 or Glu669) nor double mutants Gly654/Gly669 or Gly654/Glu669 influenced the binding of CaM to the EGFR-JM. This clearly shows that PKC may regulate EGF-mediated CaM signalling through phosphorylation of Thr654 whereas phosphorylation of Thr669 seems to play a CaM independent regulatory role. The role of both residues in the EGFR-calmodulin interaction was also studied in silico. Our modelling work supports a scenario where Thr654 from the JM domain interacts with Glu120 in the calmodulin molecule. Phosphorylation of Thr654 or Glu654 substitution creates a repulsive electrostatic force that would diminish CaM binding to the JM domain. These results are in line with the Biacore experiments showing a weak binding of the CaM to the JM domain with Thr654 mutated to Glu. Furthermore, these results provide a hypothesis to how CaM binding to EGFR might both positively and negatively interfere with EGFR-activity. © 2006 Elsevier Inc. All rights reserved.

  • 264.
    Aigbavbiere, Ernest
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ekologi.
    How does predation from fish influence the benthic invertebrates’ species composition in the Phragmites australis and Chara vegetation of Lake Takern?2011Självständigt arbete på avancerad nivå (masterexamen), 60 poäng / 90 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Predation is one of the important selective factors that regulate the species composition of benthic invertebrate communities. The study objective was to investigate the invertebrate distribution in two contrasting habitats in Lake Takern, southern Sweden, submerged Chara vegetation and emergent Phragmites australis vegetation, and to investigate the influence of predation from fish on certain invertebrates. Laboratory studies were used to estimate handling time and the intake rate (mg/sec) by the fish based on the optimal foraging model. In the field, fish and invertebrates were collected with gill nets and hand nets respectively and the fish gut content was analyzed. In total, sixteen invertebrates’ taxa were collected from the two habitats. The proportion of the invertebrate’s overlaps from each of the habitat was calculated by Renkonen index and with Sorensen diversity index. Both indices showed a similarity larger than 65%, indicating that there was no significant difference in the invertebrates’ distribution in the P. australis and the Chara habitat. The fish caught with the gill nets were: roach (Rutilus rutilus), perch (Perca fluviatilis), tench (Tinca tinca), and rudd (Scardinius erythrophthalmus). The caught perch had eaten: Asellus aquaticus, Gammarus lacustris, Corixidae, and the larvae of Chironomidae and Zygoptera.A comparison was made on the invertebrates found in the field and the ones observed from the gut of the perch, and the findings were that the invertebrates that had more occurrence in the gut were less in proportion in the benthic samples. In the laboratory experiment perch ( Perca fluviatilis) was used as the predator fish and the prey organisms were Asellus aquaticus,Gammarus pulex, and Corixidae of three size categories. The results showed that perch handling time for A.aquaticus of the different size categories, was not significantly different (p>0.05); and the same results were valid for Corixidae and G. pulex. However, the intake rate of perch across the prey and their size categories were significantly different. The handling time was not significantly different which means that the predator fish will gain more in terms of intake rate as it prey on larger size prey items, thus harmonizing with the optimum foraging theory.

     

  • 265.
    Aigbavbiere, Ernest
    Linköpings universitet, Institutionen för tema, Tema vatten i natur och samhälle.
    The effects of heavy metals on denitification in a wetland sediment..2006Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [en]

    Wetlands water quality is influenced by the anthopogenic activities in the catchments’ areas. Wastewaters from the urban storm, agricultural runoff and sewage treatment often end up in wetlands before flowing to rivers, lakes and the sea. A lot of pollutants are readily transported in these wastewaters, thus subjecting the wetland ecosystem into a continuous resilience. Importantly, heavy metals like Cu, Zn, and Pb etc. are constituents of such pollutants in the wastewaters.

    The study has as a specific objective to investigate the effects of heavy metal Cu, Zn and Pb on denitrification, an important ecosystem process and service. In a wetland situation, denitrification is a permanent nitrogen removal process accounting for about 90% of the total nitrogen removal.

    The research was carried out in the laboratory and sediment samples were taken from a constructed wetland in Linkoping. We employed acetylene inhibition technique in obtaining N2O as a product resulting from nitrate reduction. The treatments (Cu, Zn and Pb) levels were 100 mg/kg, 250 mg/kg, 500 mg/kg and 1000 mg/kg of sediment, in three replicates and a control.

    Samplings of the assay were taken within 24hours. Gas chromatography was used to analyse and quantify N2O in the various samples. A linear regression analysis was carried out with Windows Excel and SPSS to compare the various treatments with the control at 95% confidence level.

    The results show that there were no inhibitions of denitrification at 100 mg/kg sediment treatment level for any of the element. Inhibition of denitrification was observed at treatment levels 500 mg/kg and 1000 mg/kg of sediment. The rate of nitrate reduction was compared from the slope of the regression curve. The rate for Cu at 500 mg and 1000 mg /kg of sediment was moderately related to that of the control, Zn shows a similar trend but a higher rate in some samples, while Pb shows more inhibition.

  • 266.
    Aigner, Mats
    et al.
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska högskolan.
    Tjatyrko, Vitalij
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska fakulteten.
    Nyagahakwa, Venuste
    National University of Rwanda, Rwanda .
    ON COUNTABLE FAMILIES OF SETS WITHOUT THE BAIRE PROPERTY2013Ingår i: Colloquium Mathematicum, ISSN 0010-1354, E-ISSN 1730-6302, Vol. 133, nr 2, s. 179-187Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We suggest a method of constructing decompositions of a topological space X having an open subset homeomorphic to the space (R-n , tau), where n is an integer greater than= 1 and tau is any admissible extension of the Euclidean topology of R-n (in particular, X can be a finite-dimensional separable metrizable manifold), into a countable family F of sets (dense in X and zero-dimensional in the case of manifolds) such that the union of each non-empty proper subfamily of F does not have the Baire property in X.

  • 267.
    Aigner, Mats
    et al.
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska fakulteten.
    Tjatyrko, Vitalij
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska fakulteten.
    Nyagahakwa, Venuste
    National University of Rwanda, Rwanda.
    THE ALGEBRA OF SEMIGROUPS OF SETS2015Ingår i: Mathematica Scandinavica, ISSN 0025-5521, E-ISSN 1903-1807, Vol. 116, nr 2, s. 161-170Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We study the algebra of semigroups of sets (i.e. families of sets closed under finite unions) and its applications. For each n greater than 1 we produce two finite nested families of pairwise different semigroups of sets consisting of subsets of R" without the Baire property.

  • 268.
    Aijaz, Asim
    Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Design and Characterisation of A SynchronousCo-Axuak Double Magnetron Sputtering System2009Självständigt arbete på avancerad nivå (masterexamen), 30 poäng / 45 hpStudentuppsats (Examensarbete)
    Abstract [en]

    High power impulse magnetron sputtering (HiPIMS) is a novel pulsed power technique. In HiPIMS, high power pulses are applied to the target for short duration with a low duty factor. It provides a high degree of ionization of the sputtered material (in some cases up to 90%) and a high plasma density (1019 m-3) which results in densification of the grown films. Recently a large side-transport of the sputtered material has been discovered, meaning that the sputtered material is transported radially outwards, parallel to the cathode surface. In this research, we use this effect and study the side-ways deposition of thin films. We designed a new magnetron sputtering system, consisting of two opposing magnetrons with similar polarity. Ti films were grown on Si using the side-ways transport of the sputtered material. Scanning electron microscope was employed to investigate the microstructure of the grown films. Optical emission spectroscopy (OES) measurements were made for investigating the ionized fraction of the sputtered material while Langmuir probe measurements were made for evaluating the plasma parameters such as electron density. The conclusion is that the system works well for side-ways deposition and it can be useful for coating the interior of cylindrically shaped objects. It is a promising technique that should be used in industry.

  • 269.
    Aijaz, Asim
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    HiPIMS-based Novel Deposition Processes for Thin Films2012Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In this research, high power impulse magnetron sputtering (HiPIMS) based new deposition processes are introduced to address; the issue of low degree of ionization of C in magnetron sputtering discharges, and the difficulty encountered in thin film deposition on complex-shaped surfaces. The issue of low degree of C ionization is addressed by introducing a new strategy which is based on promoting the electron impact ionization ofC by increasing the electron temperature in the plasma discharge using Ne, instead of conventionally used Ar. The Ne-based HiPIMS process provides highly ionized C fluxes which are essential for the synthesis of high-density and sp3 rich amorphous carbon (a-C) thin films such as diamond-like carbon (DLC) and tetrahedral a-C (ta-C). The feasibility of coating complex-shaped surfaces is demonstrated by using the dual-magnetron approach in an open-field (magnetic field of the magnetrons) configuration and performing sideways deposition of Ti films. The HiPIMS-based open-field configuration process enhances the sideways transport of the sputtered flux — an effect which is observed in the case of HiPIMS.

    The characterization of the Ne-HiPIMS discharge using a Langmuir probe and mass spectrometry shows that it provides an increase in the electron temperature resulting in an order of magnitude decrease in the mean ionization length of the sputtered C as compared to the conventional Ar-HiPIMS discharge. The C1+ ion energy distribution functions exhibit the presence of an energetic C1+ ion population and a substantial increase in the total C1+ ion flux. The higher C1+ ion flux facilitates the growth of sp3 rich carbon films with mass densities, measured by x-ray reflectometry, reaching as high as approx. 2.8 gcm-3.

    The dual-magnetron open-field configuration process is operated in DCMS as well as in HiPIMS modes. The plasma characterization, performed by Langmuir probe measurements and optical emission spectroscopy, shows that the plasma density in the Ti-HiPIMS discharge is higher than that of the Ti-DCMS discharge. This results in the higher ionized fraction of the sputtered Ti in the case of HiPIMS. The film uniformity and the deposition rate of the film growth, obtained by employing scanning electron microscopy, demonstrate that the sideways deposition approach can be used for depositing thin films on complex-shaped surfaces.

    Delarbeten
    1. A strategy for increased carbon ionization in magnetron sputtering discharges
    Öppna denna publikation i ny flik eller fönster >>A strategy for increased carbon ionization in magnetron sputtering discharges
    Visa övriga...
    2012 (Engelska)Ingår i: Diamond and related materials, ISSN 0925-9635, E-ISSN 1879-0062, Vol. 23, s. 1-4Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A strategy that facilitates a substantial increase of carbon ionization in magnetron sputtering discharges is presented in this work. The strategy is based on increasing the electron temperature in a high power impulse magnetron sputtering discharge by using Ne as the sputtering gas. This allows for the generation of an energetic C+ ion population and a substantial increase in the C+ ion flux as compared to a conventional Ar-HiPIMS process. A direct consequence of the ionization enhancement is demonstrated by an increase in the mass density of the grown films up to 2.8 g/cm3; the density values achieved are substantially higher than those obtained from conventional magnetron sputtering methods.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2012
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-74315 (URN)10.1016/j.diamond.2011.12.043 (DOI)000302887600001 ()
    Forskningsfinansiär
    Vetenskapsrådet, 621-2008-3222 623-2009-7348
    Tillgänglig från: 2012-01-24 Skapad: 2012-01-24 Senast uppdaterad: 2017-12-08Bibliografiskt granskad
    2. Dual-magnetron open field sputtering system for sideways deposition of thin films
    Öppna denna publikation i ny flik eller fönster >>Dual-magnetron open field sputtering system for sideways deposition of thin films
    2010 (Engelska)Ingår i: SURFACE and COATINGS TECHNOLOGY, ISSN 0257-8972, Vol. 204, nr 14, s. 2165-2169Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A dual-magnetron system for deposition inside tubular substrates has been developed. The two magnetrons are facing each other and have opposing magnetic fields forcing electrons and thereby also ionized material to be transported radially towards the substrate. The depositions were made employing direct current magnetron sputtering (DCMS) and high power impulse magnetron sputtering (HiPIMS). To optimize the deposition rate, the system was characterized at different separation distances between the magnetrons under the same sputtering conditions. The deposition rate is found to increase with increasing separation distance independent of discharge technique. The emission spectrum from the HiPIMS plasma shows a highly ionized fraction of the sputtered material. The electron densities of the order of 10(16) m(-3) and 10(18) m(-3) have been determined in the DCMS and the HiPIMS plasma discharges respectively. The results demonstrate a successful implementation of the concept of sideways deposition of thin films providing a solution for coating complex shaped surfaces.

    Nyckelord
    Dual-magnetron, Open field configuration, Sideways deposition, HiPIMS, HPPMS, DCMS
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-54766 (URN)10.1016/j.surfcoat.2009.11.044 (DOI)000275920900009 ()
    Tillgänglig från: 2010-04-09 Skapad: 2010-04-09 Senast uppdaterad: 2015-05-28
  • 270.
    Aijaz, Asim
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Synthesis of Carbon-based and Metal-Oxide Thin Films using High Power Impulse Magnetron Sputtering2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The work presented in this thesis deals with synthesis of carbon-based as well as metal-oxide thin films using highly ionized plasmas. The principal deposition method employed was high power impulse magnetron sputtering (HiPIMS). The investigations on plasma chemistry, plasma energetics, plasma-film interactions and its correlation to film growth and resulting film properties were made. The thesis is divided into two parts: (i) HiPIMS-based deposition of carbon-based thin films and (ii) HiPIMS-based deposition of metal-oxide thin films.

    In the first part of the thesis, HiPIMS based strategies are presented that were developed to address the fundamental issues of low degree of carbon ionization and low deposition rates of carbon film growth in magnetron sputtering. In the first study, a new strategy was introduced for increasing the degree of ionization of sputtered carbon via increasing the electron temperature in the discharge by using a higher ionization potential buffer gas (Ne) in place of commonly used Ar. A direct consequence of enhanced electron temperatures was observed in the form of measured large fluxes of ionized carbon at the substrate position. Consequently, high mass densities of the resulting amorphous carbon (a-C) thin films reaching 2.8 g/cm3 were obtained.

    In another study, feasibility of HiPIMS-based high density discharges for high-rate synthesis of dense and hard a-C thin films was explored. A strategy was compiled and implemented that entailed coupling a hydrocarbon precursor gas (C2H2) with high density discharges generated by the superposition of HiPIMS and direct current magnetron sputtering (DCMS). Appropriate control of discharge density (by tuning HiPIMS/DCMS power ratio), gas phase composition and energy of the ionized depositing species lead to a route capable of providing ten-fold increase in the deposition rate of a-C film growth compared to that obtained using HiPIMS Ar discharge in the first study. The increased deposition rate was achieved without significant incorporation of H (<10 %) and with relatively high hardness (>25 GPa) and mass density (~2.32 g/cm3). The knowledge gained in this work was utilized in a subsequent work where the feasibility of adding high ionization potential buffer gas (Ne) to increase the electron temperature in an Ar/C2H2 HiPIMS discharge was explored. It was found that the increased electron temperature lead to enhanced dissociation of hydrocarbon precursor and an increased H incorporation into the growing film. The resulting a-C thin films exhibited high hardness (~ 25 GPa), mass densities in the order of 2.2 g/cm3 and H content as low as about 11%. The striking feature of the resulting films was low stress levels where the films exhibited compressive stresses in the order of 100 MPa.

    In the second part of the thesis, investigations on reactive HiPIMS discharge characteristics were made for technologically relevant metal-oxide systems. In the first study, the discharge characteristics of Ti-O and Al-O were investigated by studying the discharge current characteristics and measuring the ion flux composition. Both, Ti-O and Al-O discharges were dominated by large fluxes of ionized metallic as well as sputtering and reactive gases species. The generation of large ionized fluxes influenced the discharge characteristics consequently surpassing the changes in the secondary electron emission yields which, in the case of DCMS discharges entail contrasting behavior of the discharge voltage for the two material systems. The study also suggested that the source of oxygen ions in the case of reactive HiPIMS is both, the target surface (via sputtering) as well as gas phase.

    In a subsequent study, the knowledge gained from the studies on metal-oxide HiPIMS discharges was utilized for investigating the behavior of reactive HiPIMS discharges related to ternary compound thin film growth. In this work Al-Si-O system, which is a promising candidate for anti-reflective and solar thermal applications, was employed to carry out the investigations under varied target compositions (Al, Al0.5Si0.5, and Al0.1Si0.9). It was found that the discharge current behavior of metal and oxide modes of Al-Si-O HiPIMS discharges were similar to those of Al-O and were independent of the target composition. The influence of energy and composition of the ionized depositing fluxes on the film growth was also investigated. It was shown that stoichiometric Al-Si-O thin films exhibiting a refractive index below 1.6 (which is desired for anti-reflective applications) can be grown. Furthermore, the refractive index and chemical composition of the resulting films were found to be unchanged with respect to the energy of the depositing species.

    The effect of ionized deposition fluxes that are generated in metal-oxide HiPIMS discharges was also investigated for the phase composition and optical properties of TiO2 thin films. It was found that energetic and ionized sputtered flux in reactive HiPIMS can be used to tailor the phase formation of the TiO2 films with high peak powers facilitating the rutile phase while the anatase phase can be obtained using low peak powers. It was also demonstrated that using HiPIMS, these phases can be obtained at room temperature without external substrate heating or  post-deposition annealing. The results on plasma and film properties were also compared with DCMS.

    Delarbeten
    1. A strategy for increased carbon ionization in magnetron sputtering discharges
    Öppna denna publikation i ny flik eller fönster >>A strategy for increased carbon ionization in magnetron sputtering discharges
    Visa övriga...
    2012 (Engelska)Ingår i: Diamond and related materials, ISSN 0925-9635, E-ISSN 1879-0062, Vol. 23, s. 1-4Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A strategy that facilitates a substantial increase of carbon ionization in magnetron sputtering discharges is presented in this work. The strategy is based on increasing the electron temperature in a high power impulse magnetron sputtering discharge by using Ne as the sputtering gas. This allows for the generation of an energetic C+ ion population and a substantial increase in the C+ ion flux as compared to a conventional Ar-HiPIMS process. A direct consequence of the ionization enhancement is demonstrated by an increase in the mass density of the grown films up to 2.8 g/cm3; the density values achieved are substantially higher than those obtained from conventional magnetron sputtering methods.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2012
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-74315 (URN)10.1016/j.diamond.2011.12.043 (DOI)000302887600001 ()
    Forskningsfinansiär
    Vetenskapsrådet, 621-2008-3222 623-2009-7348
    Tillgänglig från: 2012-01-24 Skapad: 2012-01-24 Senast uppdaterad: 2017-12-08Bibliografiskt granskad
    2. Principles for designing sputtering-based strategies for high-rate synthesis of dense and hard hydrogenated amorphous carbon thin films
    Öppna denna publikation i ny flik eller fönster >>Principles for designing sputtering-based strategies for high-rate synthesis of dense and hard hydrogenated amorphous carbon thin films
    Visa övriga...
    2014 (Engelska)Ingår i: Diamond and related materials, ISSN 0925-9635, E-ISSN 1879-0062, Vol. 44, s. 117-122Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In the present study we contribute to the understanding that is required for designing sputtering-based routes for high rate synthesis of hard and dense amorphous carbon (a-C) films. We compile and implement a strategy for synthesis of a-C thin films that entails coupling a hydrocarbon gas (acetylene) with high density discharges generated by the superposition of high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS). Appropriate control of discharge density (by tuning HiPIMS/DCMS power ratio), gas phase composition and energy of the ionized depositing species leads to a route capable of providing ten-fold increase in the deposition rate of a-C film growth compared to HiPIMS Ar discharge (Aijaz et al. Diamond and Related Materials 23 (2012) 1). This is achieved without significant incorporation of H (< 10 %) and with relatively high hardness (> 25 GPa) and mass density (~2.32 g/cm3). Using our experimental data together with Monte-Carlo computer simulations and data from the literature we suggest that: (i) dissociative reactions triggered by the interactions of energetic discharge electrons with hydrocarbon gas molecules is an important additional (to the sputtering cathode) source of film forming species and (ii) film microstructure and film hydrogen content are primarily controlled by interactions of energetic plasma species with surface and sub-surface layers of the growing film.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2014
    Nyckelord
    Hydrogenated amorphous carbon, DLC, HiPIMS, reactive sputtering
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-104261 (URN)10.1016/j.diamond.2014.02.014 (DOI)000335272800017 ()
    Tillgänglig från: 2014-02-13 Skapad: 2014-02-13 Senast uppdaterad: 2017-12-06Bibliografiskt granskad
    3. Synthesis of amorphous carbon thin films using acetylene-based high power impulse magnetron sputtering discharges
    Öppna denna publikation i ny flik eller fönster >>Synthesis of amorphous carbon thin films using acetylene-based high power impulse magnetron sputtering discharges
    Visa övriga...
    2013 (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Amorphous carbon (a-C) thin films are synthesized using high power impulse magnetron sputtering (HiPIMS) based Ne-Ar/C2H2 discharges. Plasma properties and film growth are investigated under different gas phase composition and operating pressures. Film mass densities, H content, hardness and compressive stresses are measured. Mass densities in the order of 2.2 g/cm3, hardness close to 25 GPa and H content as low as 11% are obtained. The film properties manifest a dependence on energy and flux of the depositing species and energetic ion bombardment driven structural changes in the films are found to govern the resulting film properties.

    Nyckelord
    Diamond-like carbon, hydrogenated amorphous carbon, HiPIMS, Reactive sputtering
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-104263 (URN)
    Tillgänglig från: 2014-02-13 Skapad: 2014-02-13 Senast uppdaterad: 2014-02-13Bibliografiskt granskad
    4. Understanding the discharge current behavior in reactive high power impulse magnetron sputtering of oxides
    Öppna denna publikation i ny flik eller fönster >>Understanding the discharge current behavior in reactive high power impulse magnetron sputtering of oxides
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    2013 (Engelska)Ingår i: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 113, nr 13Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The discharge current behavior in reactive high power impulse magnetron sputtering (HiPIMS) of Ti-O and Al-O is investigated. It is found that for both metals, the discharge peak current significantly increases in the oxide mode in contrast to the behavior in reactive direct current magnetron sputtering where the discharge current increases for Al but decreases for Ti when oxygen is introduced. In order to investigate the increase in the discharge current in HiPIMS-mode, the ionic contribution of the discharge in the oxide and metal mode is measured using time-resolved mass spectrometry. The energy distributions and time evolution are investigated during the pulse-on time as well as in the post-discharge. In the oxide mode, the discharge is dominated by ionized oxygen, which has been preferentially sputtered from the target surface. The ionized oxygen determines the discharge behavior in reactive HiPIMS.

    Ort, förlag, år, upplaga, sidor
    American Institute of Physics (AIP), 2013
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-91256 (URN)10.1063/1.4799199 (DOI)000317238000006 ()
    Tillgänglig från: 2013-04-18 Skapad: 2013-04-18 Senast uppdaterad: 2017-12-06
    5. Exploring the potential of high power impulse magnetron sputtering for the synthesis of scratch resistant, antireflective coatings
    Öppna denna publikation i ny flik eller fönster >>Exploring the potential of high power impulse magnetron sputtering for the synthesis of scratch resistant, antireflective coatings
    Visa övriga...
    2013 (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Broad band anti-reflective multilayer coatings require the use of a low-index material as a top layer. Normally SiO2 is used which exhibits sufficiently low refractive index (~1.5 at 550 nm) yet its low hardness (~10 GPa) hinders its application in abrasive environments. A strategy to circumnavigate these limitations is the synthesis of multicomponent materials that combine good mechanical and optical performance. In this work we synthesize Al-Si-O thin films seeking to combine the low refractive index of SiO2 and the relatively high hardness of Al2O3. The potential of reactive high power impulse magnetron sputtering (HiPIMS) for synthesizing Al-Si-O suitable for top-layers in anti-reflective coating stacks is explored by depositing films in an Ar+O2 ambient under varied target compositions (Al0.5Si0.5 and Al0.1Si0.9). The behavior of discharge current in metal and oxide mode is correlated with the plasma composition, plasma energetics as well as target surface composition in order to obtain information about the chemical nature and the energy of the film forming species. Plasma composition and plasma energetics are investigated by measuring electron density, electron temperature as well as energy distributions and as fluxes of Ar+, Al+, Si+ and O+ ions. Monte-Carlo based computer simulations are employed to assess the ion-target surface interactions to gain insight into the discharge characteristics as well as film growth. The properties of the grown films (chemical composition, mechanical and optical properties) are investigated and an understanding of the reactive HiPIMS-based growth of anti-reflective Al-Si-O thin films is established. For reference, the plasma and film properties of Al-O are also studied.

    Nyckelord
    Al-Si-O, anti-reflective coatings, optical coatings, HiPIMS, reactive sputtering
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-104264 (URN)
    Tillgänglig från: 2014-02-13 Skapad: 2014-02-13 Senast uppdaterad: 2014-02-13Bibliografiskt granskad
    6. Effect of peak power in reactive high power impulse magnetron sputtering of titanium dioxide
    Öppna denna publikation i ny flik eller fönster >>Effect of peak power in reactive high power impulse magnetron sputtering of titanium dioxide
    Visa övriga...
    2011 (Engelska)Ingår i: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 205, nr 20, s. 4828-4831Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The effect of peak power in a high power impulse magnetron sputtering (HiPIMS) reactive deposition of TiO(2) films has been studied with respect to the deposition rate and coating properties. With increasing peak power not only the ionization of the sputtered material increases but also their energy. In order to correlate the variation in the ion energy distributions with the film properties, the phase composition, density and optical properties of the films grown with different HiPIMS-parameters have been investigated and compared to a film grown using direct current magnetron sputtering (DCMS). All experiments were performed for constant average power and pulse on time (100W and 35 mu s, respectively), different peak powers were achieved by varying the frequency of pulsing. Ion energy distributions for Ti and O and its dependence on the process conditions have been studied. It was found that films with the highest density and highest refractive index were grown under moderate HiPIMS conditions (moderate peak powers) resulting in only a small loss in mass-deposition rate compared to DCMS. It was further found that TiO2 films with anatase and rutile phases can be grown at room temperature without substrate heating and without post-deposition annealing.

    Ort, förlag, år, upplaga, sidor
    Elsevier Science B.V., Amsterdam., 2011
    Nyckelord
    HiPIMS; Titanium dioxide; Rutile; Anatase; Reactive sputtering; TiO(2)
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-69795 (URN)10.1016/j.surfcoat.2011.04.071 (DOI)000292361400013 ()
    Anmärkning

    Original Publication: Montri Aiempanakit, Ulf Helmersson, Asim Aijaz, Petter Larsson, Roger Magnusson, Jens Jensen and Tomas Kubart, Effect of peak power in reactive high power impulse magnetron sputtering of titanium dioxide, 2011, Surface & Coatings Technology, (205), 20, 4828-4831. http://dx.doi.org/10.1016/j.surfcoat.2011.04.071 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/

    Tillgänglig från: 2011-08-10 Skapad: 2011-08-08 Senast uppdaterad: 2017-12-08
  • 271.
    Aijaz, Asim
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Aiempanakit, Montri
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan. Present address: Department of Physics, Faculty of Science, Silpakorn University, Nakhon Pathom, Thailand.
    Bruns, Stefan
    Fraunhofer Institute for Surface Engineering and Thin Films (IST), Germany.
    Helmersson, Ulf
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Vergöhl, Michael
    Fraunhofer Institute for Surface Engineering and Thin Films (IST), Germany.
    Sarakinos, Kostas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Exploring the potential of high power impulse magnetron sputtering for the synthesis of scratch resistant, antireflective coatings2013Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Broad band anti-reflective multilayer coatings require the use of a low-index material as a top layer. Normally SiO2 is used which exhibits sufficiently low refractive index (~1.5 at 550 nm) yet its low hardness (~10 GPa) hinders its application in abrasive environments. A strategy to circumnavigate these limitations is the synthesis of multicomponent materials that combine good mechanical and optical performance. In this work we synthesize Al-Si-O thin films seeking to combine the low refractive index of SiO2 and the relatively high hardness of Al2O3. The potential of reactive high power impulse magnetron sputtering (HiPIMS) for synthesizing Al-Si-O suitable for top-layers in anti-reflective coating stacks is explored by depositing films in an Ar+O2 ambient under varied target compositions (Al0.5Si0.5 and Al0.1Si0.9). The behavior of discharge current in metal and oxide mode is correlated with the plasma composition, plasma energetics as well as target surface composition in order to obtain information about the chemical nature and the energy of the film forming species. Plasma composition and plasma energetics are investigated by measuring electron density, electron temperature as well as energy distributions and as fluxes of Ar+, Al+, Si+ and O+ ions. Monte-Carlo based computer simulations are employed to assess the ion-target surface interactions to gain insight into the discharge characteristics as well as film growth. The properties of the grown films (chemical composition, mechanical and optical properties) are investigated and an understanding of the reactive HiPIMS-based growth of anti-reflective Al-Si-O thin films is established. For reference, the plasma and film properties of Al-O are also studied.

  • 272.
    Aijaz, Asim
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Louring, Sascha
    Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Denmark.
    Jensen, Jens
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska högskolan.
    Sarakinos, Kostas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Helmersson, Ulf
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Synthesis of amorphous carbon thin films using acetylene-based high power impulse magnetron sputtering discharges2013Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Amorphous carbon (a-C) thin films are synthesized using high power impulse magnetron sputtering (HiPIMS) based Ne-Ar/C2H2 discharges. Plasma properties and film growth are investigated under different gas phase composition and operating pressures. Film mass densities, H content, hardness and compressive stresses are measured. Mass densities in the order of 2.2 g/cm3, hardness close to 25 GPa and H content as low as 11% are obtained. The film properties manifest a dependence on energy and flux of the depositing species and energetic ion bombardment driven structural changes in the films are found to govern the resulting film properties.

  • 273.
    Aijaz, Asim
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan. Uppsala University, Sweden.
    Louring, Sascha
    Aarhus University, Denmark; Danish Technology Institute, Denmark.
    Lundin, Daniel
    University of Paris Saclay, France.
    Kubart, Tomas
    Uppsala University, Sweden.
    Jensen, Jens
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Sarakinos, Kostas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Nanodesign. Linköpings universitet, Tekniska fakulteten.
    Helmersson, Ulf
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska fakulteten.
    Synthesis of hydrogenated diamondlike carbon thin films using neon-acetylene based high power impulse magnetron sputtering discharges2016Ingår i: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 34, nr 6, artikel-id 061504Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hydrogenated diamondlike carbon (DLC:H) thin films exhibit many interesting properties that can be tailored by controlling the composition and energy of the vapor fluxes used for their synthesis. This control can be facilitated by high electron density and/or high electron temperature plasmas that allow one to effectively tune the gas and surface chemistry during film growth, as well as the degree of ionization of the film forming species. The authors have recently demonstrated by adding Ne in an Ar-C high power impulse magnetron sputtering (HiPIMS) discharge that electron temperatures can be effectively increased to substantially ionize C species [Aijaz et al., Diamond Relat. Mater. 23, 1 (2012)]. The authors also developed an Ar-C2H2 HiPIMS process in which the high electron densities provided by the HiPIMS operation mode enhance gas phase dissociation reactions enabling control of the plasma and growth chemistry [Aijaz et al., Diamond Relat. Mater. 44, 117 (2014)]. Seeking to further enhance electron temperature and thereby promote electron impact induced interactions, control plasma chemical reaction pathways, and tune the resulting film properties, in this work, the authors synthesize DLC: H thin films by admixing Ne in a HiPIMS based Ar/C2H2 discharge. The authors investigate the plasma properties and discharge characteristics by measuring electron energy distributions as well as by studying discharge current characteristics showing an electron temperature enhancement in C2H2 based discharges and the role of ionic contribution to the film growth. These discharge conditions allow for the growth of thick (amp;gt;1 mu m) DLC: H thin films exhibiting low compressive stresses (similar to 0.5 GPa), high hardness (similar to 25 GPa), low H content (similar to 11%), and density in the order of 2.2 g/cm(3). The authors also show that film densification and change of mechanical properties are related to H removal by ion bombardment rather than subplantation. (C) 2016 American Vacuum Society.

  • 274.
    Aijaz, Asim
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Sarakinos, Kostas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Lundin, Daniel
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Brenning, Nils
    Royal Institute of Technology.
    Helmersson, Ulf
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    A strategy for increased carbon ionization in magnetron sputtering discharges2012Ingår i: Diamond and related materials, ISSN 0925-9635, E-ISSN 1879-0062, Vol. 23, s. 1-4Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A strategy that facilitates a substantial increase of carbon ionization in magnetron sputtering discharges is presented in this work. The strategy is based on increasing the electron temperature in a high power impulse magnetron sputtering discharge by using Ne as the sputtering gas. This allows for the generation of an energetic C+ ion population and a substantial increase in the C+ ion flux as compared to a conventional Ar-HiPIMS process. A direct consequence of the ionization enhancement is demonstrated by an increase in the mass density of the grown films up to 2.8 g/cm3; the density values achieved are substantially higher than those obtained from conventional magnetron sputtering methods.

  • 275.
    Aijaz, Asim
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Sarakinos, Kostas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Raza, Mohsin
    Chimie des Interactions Plasma-Surface (ChIPS), University of Mons, Belgium.
    Jensen, Jens
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska högskolan.
    Helmersson, Ulf
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Principles for designing sputtering-based strategies for high-rate synthesis of dense and hard hydrogenated amorphous carbon thin films2014Ingår i: Diamond and related materials, ISSN 0925-9635, E-ISSN 1879-0062, Vol. 44, s. 117-122Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In the present study we contribute to the understanding that is required for designing sputtering-based routes for high rate synthesis of hard and dense amorphous carbon (a-C) films. We compile and implement a strategy for synthesis of a-C thin films that entails coupling a hydrocarbon gas (acetylene) with high density discharges generated by the superposition of high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS). Appropriate control of discharge density (by tuning HiPIMS/DCMS power ratio), gas phase composition and energy of the ionized depositing species leads to a route capable of providing ten-fold increase in the deposition rate of a-C film growth compared to HiPIMS Ar discharge (Aijaz et al. Diamond and Related Materials 23 (2012) 1). This is achieved without significant incorporation of H (< 10 %) and with relatively high hardness (> 25 GPa) and mass density (~2.32 g/cm3). Using our experimental data together with Monte-Carlo computer simulations and data from the literature we suggest that: (i) dissociative reactions triggered by the interactions of energetic discharge electrons with hydrocarbon gas molecules is an important additional (to the sputtering cathode) source of film forming species and (ii) film microstructure and film hydrogen content are primarily controlled by interactions of energetic plasma species with surface and sub-surface layers of the growing film.

  • 276.
    Aikawa, Hiroaki
    et al.
    Hokkaido Univ, Japan.
    Björn, Anders
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska fakulteten.
    Björn, Jana
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska fakulteten.
    Shanmugalingam, Nageswari
    Univ Cincinnati, OH 45221 USA.
    Dichotomy of global capacity density in metric measure spaces2018Ingår i: Advances in Calculus of Variations, ISSN 1864-8258, E-ISSN 1864-8266, Vol. 11, nr 4, s. 387-404Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The variational capacity cap(p) in Euclidean spaces is known to enjoy the density dichotomy at large scales, namely that for every E subset of R-n, infx is an element of R(n)cap(p)(E boolean AND B(x, r), B(x, 2r))/cap(p)(B(x, r), B(x, 2r)) is either zero or tends to 1 as r -amp;gt; infinity. We prove that this property still holds in unbounded complete geodesic metric spaces equipped with a doubling measure supporting a p-Poincare inequality, but that it can fail in nongeodesic metric spaces and also for the Sobolev capacity in R-n. It turns out that the shape of balls impacts the validity of the density dichotomy. Even in more general metric spaces, we construct families of sets, such as John domains, for which the density dichotomy holds. Our arguments include an exact formula for the variational capacity of superlevel sets for capacitary potentials and a quantitative approximation from inside of the variational capacity.

  • 277.
    Ail, Ujwala
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Jafari, Mohammad Javad
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Wang, Hui
    Linköpings universitet, Institutionen för teknik och naturvetenskap. Linköpings universitet, Tekniska fakulteten.
    Ederth, Thomas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Berggren, Magnus
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Crispin, Xavier
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Thermoelectric Properties of Polymeric Mixed Conductors2016Ingår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 26, nr 34, s. 6288-6296Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The thermoelectric (TE) phenomena are intensively explored by the scientific community due to the rather inefficient way energy resources are used with a large fraction of energy wasted in the form of heat. Among various materials, mixed ion-electron conductors (MIEC) are recently being explored as potential thermoelectrics, primarily due to their low thermal conductivity. The combination of electronic and ionic charge carriers in those inorganic or organic materials leads to complex evolution of the thermovoltage (Voc) with time, temperature, and/or humidity. One of the most promising organic thermoelectric materials, poly(3,4-ethyelenedioxythiophene)-polystyrene sulfonate (PEDOT-PSS), is an MIEC. A previous study reveals that at high humidity, PEDOT-PSS undergoes an ionic Seebeck effect due to mobile protons. Yet, this phenomenon is not well understood. In this work, the time dependence of the Voc is studied and its behavior from the contribution of both charge carriers (holes and protons) is explained. The presence of a complex reorganization of the charge carriers promoting an internal electrochemical reaction within the polymer film is identified. Interestingly, it is demonstrated that the time dependence behavior of Voc is a way to distinguish between three classes of polymeric materials: electronic conductor, ionic conductor, and mixed ionic–electronic conductor

  • 278.
    Ail, Ujwala
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Ullah Khan, Zia
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Granberg, Hjalmar
    Innventia AB, Sweden.
    Berthold, Fredrik
    Innventia AB, Sweden.
    Parasuraman, Rajasekar
    Mat Research Centre, India.
    Urnarji, Arun M.
    Mat Research Centre, India.
    Slettengren, Kerstin
    Innventia AB, Sweden.
    Pettersson, Henrik
    Innventia AB, Sweden.
    Crispin, Xavier
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Room temperature synthesis of transition metal silicide-conducting polymer micro-composites for thermoelectric applications2017Ingår i: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 225, s. 55-63Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Organic polymer thermoelectrics (TE) as well as transition metal (TM) silicides are two thermoelectric class of materials of interest because they are composed of atomic elements of high abundatice; which is a prerequisite for mass implementation of thermoelectric (TE) solutions for solar and waste heat recovery. But both materials have drawbacks when it comes to finding low-cost manufacturing. The metal silicide needs high temperature (amp;gt;1000 degrees C) for creating TE legs in a device from solid powder, but it is easy to achieve long TE legs in this case. On the contrary, organic TEs are synthesized at low temperature from solution. However, it is difficult to form long legs or thick films because of their low solubility. In this work, we propose a novel method for the room temperature synthesis of TE composite containing the microparticles of chromium disilicide; CrSi2 (inorganic filler) in an organic matrix of nanofibrillated cellulose-poly(3,4-ethyelenedioxythiophene)-polystyrene sulfonate (NFC-PEDOT:PSS). With this method, it is easy to create long TE legs in a room temperature process. The originality of the approach is the use of conducting polymer aerogel microparticles mixed with CrSi2 microparticles to obtain a composite solid at room temperature under pressure. We foresee that the method can be scaled up to fabricate and pattern TE modules. The composite has an electrical conductivity (sigma) of 5.4 +/- 0.5 S/cm and the Seebeck coefficient (a) of 88 +/- 9 mu V/K, power factor (alpha(2)sigma) of 4 +/- 1 mu Wm(-1) K-2 at room temperature. At a temperature difference of 32 degrees C, the output power/unit area drawn across the load, with the resistance same as the internal resistance of the device is 0.6 +/- 0.1 mu W/cm(2). (C) 2017 Elsevier B.V. All rights reserved.

  • 279.
    Aili, Daniel
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Enander, Karin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Baltzer, Lars
    Division of Organic Chemistry, Department of Biochemistry and Organic Chemistry, BMC, Box 576, Uppsala UniVersity, SE-751 23 Uppsala, Sweden.
    Liedberg, Bo
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Assembly of Polypeptide-Functionalized Gold Nanoparticles through a Heteroassociation- and Folding-Dependent Bridging2008Ingår i: Nano letters (Print), ISSN 1530-6984, E-ISSN 1530-6992, Vol. 8, nr 8, s. 2473-2478Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Gold nanoparticles were functionalized with a synthetic polypeptide, de novo-designed to associate with a charge complementary linker polypeptide in a folding-dependent manner. A heterotrimeric complex that folds into two disulphide-linked four-helix bundles is formed when the linker polypeptide associates with two of the immobilized peptides. The heterotrimer forms in between separate particles and induces a rapid and extensive aggregation with a well-defined interparticle spacing. The aggregated particles are redispersed when the disulphide bridge in the linker polypeptide is reduced.

  • 280.
    Aili, Daniel
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Enander, Karin
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Baltzer, Lars
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Liedberg, Bo
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Synthetic de novo designed polypeptides for control of nanoparticle assembly and biosensing2007Ingår i: Bionanotechnology; from self-assembly to cellbiology,2007, London: Biochemical Society Transactions , 2007, s. 532-Konferensbidrag (Refereegranskat)
    Abstract [en]

         

  • 281.
    Aili, Daniel
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Enander, Karin
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Lundström, Ingemar
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad Fysik.
    Baltzer, Lars
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Liedberg, Bo
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Towards novel functional materials and sensors using de novo designed polypeptides on gold nanoparticles2006Ingår i: Europtrode VIII,2006, 2006Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

        

  • 282.
    Aili, Daniel
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Enander, Karin
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Rydberg, Johan
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Lundström, Ingemar
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad Fysik.
    Baltzer, Lars
    Uppsala University.
    Liedberg, Bo
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Alpha helix-inducing dimerization of synthetic polypeptide scaffolds on gold - a model system for receptor mimicking and biosensing2004Ingår i: 8th World Congress on Biosensors,2004, 2004Konferensbidrag (Övrigt vetenskapligt)
  • 283.
    Aili, Daniel
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Enander, Karin
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Rydberg, Johan
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Lundström, Ingemar
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad Fysik.
    Baltzer, Lars
    Uppsala University.
    Liedberg, Bo
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Folding-induced aggregation of polypeptide-decorated gold nanoparticles - an nano-scale Lego for the construction of complex hybrid materials2004Ingår i: 5th International Conference on Biological Physics,2004, 2004Konferensbidrag (Övrigt vetenskapligt)
  • 284.
    Aili, Daniel
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Enander, Karin
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Rydberg, Johan
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Lundström, Ingemar
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad Fysik.
    Baltzer, Lars
    Uppsala University.
    Liedberg, Bo
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik.
    Immobilization and heterodimerisation of helix-loop-helix polypeptides on gold surfaces - a model system for peptide-surface interactions2003Ingår i: 1st World congress on Synthetic Receptors,2003, 2003Konferensbidrag (Övrigt vetenskapligt)
  • 285.
    Aili, Daniel
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Selegård, Robert
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Baltzer, Lars
    Division of Organic Chemistry, Department of Biochemistry and Organic Chemistry, BMC, Box 576, Uppsala University, SE-751 23 Uppsala, Sweden.
    Enander, Karin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Liedberg, Bo
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Colorimetric Protein Sensing by Controlled Assembly of Gold Nanoparticles Functionalized with Synthetic Receptors2009Ingår i: Small, ISSN 1613-6810, Vol. 5, nr 21, s. 2445-2452Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A strategy for colorimetric sensing of proteins, based on the induced assembly of polypeptide-functionalized gold nanoparticles, is described. Recognition was accomplished using a polypeptide sensor scaffold designed to specifically bind the model analyte, human carbonic anhydrase II (HCAII). The extent of particle aggregation, induced by the Zn2+-triggered dimerization and folding of a second polypeptide also present on the surface of the gold nanoparticle, gave a readily detectable colorimetric shift that was dependent on the concentration of the target protein. In the absence of HCAII, particle aggregation resulted in a major redshift of the plasmon peak whereas analyte binding prevented formation of dense aggregates, significantly reducing the magnitude of the redshift. The limit of detection of HCAII was estimated to be around 15 nM. The versatility of the technique was demonstrated using a second model system based on the recognition of a peptide sequence from the tobacco mosaic virus coat protein (TMVP by a recombinant antibody fragment. This strategy is proposed as a generic platform for robust and specific protein analysis that can be further developed for monitoring a wide range of target proteins.

  • 286.
    Aili, Daniel
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Selegård, Robert
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Baltzer, Lars
    Uppsala University .
    Enander, Karin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Liedberg, Bo
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Colorimetric sensing: Small 21/20092009Ingår i: Small, ISSN 1613-6810, E-ISSN 1613-6829, Vol. 5, nr 21Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    The cover picture illustrates a novel concept for colorimetric protein sensing based on the controllable assembly of polypeptide-functionalized gold nanoparticles. Recognition of the analyte is accomplished by polypeptide-based synthetic receptors immobilized on gold nanoparticles. Also present on the particle surface is a de novo-designed helix-loop-helix polypeptide that homodimerizes and folds into four-helix bundles in the presence of Zn2+, resulting in particle aggregation. Analyte binding interferes with the folding-induced aggregation, giving rise to a clearly detectable colorimetric response.

  • 287.
    Aineslahti, Emmi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi.
    Training of spider monkeys in a food-rewarded two-choice olfactory discrimination paradigm and assessment of olfactory learning and memory performance2019Självständigt arbete på avancerad nivå (masterexamen), 40 poäng / 60 hpStudentuppsats (Examensarbete)
    Abstract [en]

    There is little knowledge about olfactory learning in primates, even though primates are known to use olfaction in several behaviors including food selection and territorial defense. Therefore I assessed the olfactory learning and memory performance in five adult spider monkeys (Ateles geoffroyi) using a food-rewarded two-choice olfactory discrimination paradigm. The spider monkeys acquired the initial odor discrimination in 530-1102 trials and in a series of intramodal transfer tasks they needed 30-510 trials to reach the learning criterion. There was a significant negative correlation between the number of trials needed to reach the learning criterion and the number of transfer tasks completed. Thus, as a group, the animals displayed olfactory learning set formation. The number of trials that the spider monkeys needed in initial olfactory learning was comparable to that of other primate species tested previously but higher compared to that of other mammals such as dogs and rats. The learning speed of the spider monkeys in intramodal transfer tasks was similar to that of other mammals tested, suggesting that primates are less prepared to use olfactory cues in the initial solving of a problem but that once they learn the concept, their learning speed with novel odor discrimination problems is not generally slower than that of non-primate mammals. All spider monkeys tested reached the learning criterion in the memory tasks straight on the first testing day, that is: within 30 trials, suggesting similar long-term odor memory capabilities in spider monkeys and other mammals such as dogs, mice and rats.

  • 288.
    Aira, Naomi
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Lactate Dehydrogenase and Citrate Synthase activity in cardiac and skeletal muscle of lowland and highland tinamous2013Självständigt arbete på grundnivå (kandidatexamen), 10,5 poäng / 16 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Tinamous (Tinamidae) have the smallest heart in relation to body mass compared to any other flying bird today (Bishop 1997). This means that heart size is likely to restrict aerobic metabolism. Tinamous inhabit areas from sea level to 4800 m a.s.l., which means that the high altitude living species, Nothoprocta ornata (NO), is exposed to hypoxia. In this study the activity of the two metabolic enzymes Lactate Dehydrogenase (LDH) and Citrate Synthase (CS) was measured and the ratio between the enzyme activities calculated to examine if the small heart of the tinamous affects their aerobic/anaerobic metabolism. The activity of the two enzymes was measured in the heart and the gastrocnemius muscle in the three species Nothoprocta ornata (NO), Nothoprocta perdicaria (NP) and Gallus gallus (GG). CS activity was significantly higher in the heart compared to the skeletal muscle and LDH activity was significant higher in the skeletal muscle than in the heart in all three species. The LDH/CS ratio was significantly higher in NO’s skeletal muscle than in chickens but there was no significant difference between species in the heart. The higher ratio in NO´s muscle could be a sign of a higher anaerobic metabolism that is used in the muscles to compensate for the small heart NO have. In conclusion, the Tinamous

  • 289.
    Airaksinen, Tom
    et al.
    Linköpings universitet, Institutionen för datavetenskap.
    Byström, Erik E.
    Linköpings universitet, Institutionen för datavetenskap.
    User and Business Value: A Dual-Stakeholder Perspective on IT Systems2007Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [en]

    When discussing the value of an information technology (IT) system, the most common approach is to take on the perspective of either the organization introducing the IT system or the end users. The purpose of this thesis has been to study the values of both stakeholder groups in order to define what system characteristics are the most desirable from a dual-stakeholder point of view.

    Through a series of contextual inquiries, interviews and questionnaires, the value perceptions of end users and IT managers at a large European rail operator were investigated. The results of the study point to a high degree of similarity in the value perceptions of end users and IT managers, although the former were generally focused on short-term value while the latter also were concerned about long-term, sustaining value.

    The findings are applicable to practitioners wishing to take a dual perspective on IT value as well as academics looking to find touch points between usability and business strategy. In the context of end users and IT managers, the most important system characteristics that maximize value for both stakeholder groups were found to be Availability, Recoverability, Efficiency, Reliability and Future Proofness.

  • 290.
    Aitken, Colin
    et al.
    School of Mathematics, University of Edinburgh, Edinburgh, United Kingdom.
    Nordgaard, Anders
    Linköpings universitet, Institutionen för datavetenskap, Statistik och maskininlärning. Linköpings universitet, Filosofiska fakulteten. Swedish Police Auhtority, National Forensic Centre (NFC).
    Taroni, Franco
    School of Criminal Justice, Université de Lausanne, Lausanne, Switzerland.
    Biedermann, Alex
    School of Criminal Justice, Université de Lausanne, Lausanne, Switzerland.
    A commentary on Likelihood Ratio as Weight of Forensic Evidence: A Closer Look: by Lund, S. P., and Iyer, H. (2017). J. Res. Natl. Inst. Stand. Technol. 122:272018Ingår i: Frontiers in Genetics, ISSN 1664-8021, E-ISSN 1664-8021, Vol. 9, artikel-id 224Artikel i tidskrift (Refereegranskat)
  • 291.
    Ajjan, Fátima
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ambrogi, Martina
    Max Planck Institute Colloids and Interfaces, Germany.
    Ayalneh Tiruye, Girum
    IMDEA Energy Institute, Spain.
    Cordella, Daniela
    University of Liege ULg, Belgium.
    Fernandes, Ana M.
    POLYMAT University of Basque Country UPV EHU, Spain.
    Grygiel, Konrad
    Max Planck Institute Colloids and Interfaces, Germany.
    Isik, Mehmet
    POLYMAT University of Basque Country UPV EHU, Spain.
    Patil, Nagaraj
    University of Liege ULg, Belgium.
    Porcarelli, Luca
    POLYMAT University of Basque Country UPV EHU, Spain.
    Rocasalbas, Gillem
    KIOMedPharma, Belgium.
    Vendramientto, Giordano
    University of Bordeaux, France.
    Zeglio, Erica
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Antonietti, Markus
    Max Planck Institute Colloids and Interfaces, Germany.
    Detrembleur, Cristophe
    University of Liege ULg, Belgium.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Jerome, Christine
    University of Liege ULg, Belgium.
    Marcilla, Rebeca
    IMDEA Energy Institute, Spain.
    Mecerreyes, David
    POLYMAT University of Basque Country UPV EHU, Spain; Basque Fdn Science, Spain.
    Moreno, Monica
    POLYMAT University of Basque Country UPV EHU, Spain.
    Taton, Daniel
    University of Bordeaux, France.
    Solin, Niclas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Yuan, Jiayin
    Max Planck Institute Colloids and Interfaces, Germany.
    Innovative polyelectrolytes/poly(ionic liquid)s for energy and the environment2017Ingår i: Polymer international, ISSN 0959-8103, E-ISSN 1097-0126, Vol. 66, nr 8, s. 1119-1128Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    This paper presents the work carried out within the European project RENAISSANCE-ITN, which was dedicated to the development of innovative polyelectrolytes for energy and environmental applications. Within the project different types of innovative polyelectrolytes were synthesized such as poly(ionic liquid)s coming from renewable or natural ions, thiazolium cations, catechol functionalities or from a new generation of cheap deep eutectic monomers. Further, macromolecular architectures such as new poly(ionic liquid) block copolymers and new (semi)conducting polymer/polyelectrolyte complexes were also developed. As the final goal, the application of these innovative polymers in energy and the environment was investigated. Important advances in energy storage technologies included the development of new carbonaceous materials, new lignin/conducting polymer biopolymer electrodes, new iongels and single-ion conducting polymer electrolytes for supercapacitors and batteries and new poly(ionic liquid) binders for batteries. On the other hand, the use of innovative polyelectrolytes in sustainable environmental technologies led to the development of new liquid and dry water, new materials for water cleaning technologies such as flocculants, oil absorbers, new recyclable organocatalyst platforms and new multifunctional polymer coatings with antifouling and antimicrobial properties. All in all this paper demonstrates the potential of poly(ionic liquid)s for high-value applications in energy and enviromental areas. (c) 2017 Society of Chemical Industry

  • 292.
    Ajjan, Fátima
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Casado, N.
    University of Basque Country, Spain.
    Rebis, Tomasz
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Elfwing, Anders
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Solin, Niclas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Mecerreyes, D.
    University of Basque Country, Spain; Ikerbasque, Spain.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    High performance PEDOT/lignin biopolymer composites for electrochemical supercapacitors2016Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 4, nr 5, s. 1838-1847Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Developing sustainable organic electrode materials for energy storage applications is an urgent task. We present a promising candidate based on the use of lignin, the second most abundant biopolymer in nature. This polymer is combined with a conducting polymer, where lignin as a polyanion can behave both as a dopant and surfactant. The synthesis of PEDOT/Lig biocomposites by both oxidative chemical and electrochemical polymerization of EDOT in the presence of lignin sulfonate is presented. The characterization of PEDOT/Lig was performed by UV-Vis-NIR spectroscopy, FTIR infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, cyclic voltammetry and galvanostatic charge-discharge. PEDOT doped with lignin doubles the specific capacitance (170.4 F g(-1)) compared to reference PEDOT electrodes (80.4 F g(-1)). The enhanced energy storage performance is a consequence of the additional pseudocapacitance generated by the quinone moieties in lignin, which give rise to faradaic reactions. Furthermore PEDOT/Lig is a highly stable biocomposite, retaining about 83% of its electroactivity after 1000 charge/discharge cycles. These results illustrate that the redox doping strategy is a facile and straightforward approach to improve the electroactive performance of PEDOT.

  • 293.
    Ajjan, Fátima
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Javad Jafari, Mohammad
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Rebis, T.
    Poznan University of Tech, Poland.
    Ederth, Thomas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Spectroelectrochemical investigation of redox states in a polypyrrole/lignin composite electrode material2015Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 3, nr 24, s. 12927-12937Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report spectroelectrochemical studies to investigate the charge storage mechanism of composite polypyrrole/lignin electrodes. Renewable bioorganic electrode materials were produced by electropolymerization of pyrrole in the presence of a water-soluble lignin derivative acting as a dopant. The resulting composite exhibited enhanced charge storage abilities due to a lignin-based faradaic process, which was expressed after repeated electrochemical redox of the material. The in situ FTIR spectroelectrochemistry results show the formation of quinone groups, and reversible oxidation-reduction of these groups during charge-discharge experiments in the electrode materials. The most significant IR bands include carbonyl absorption near 1705 cm(-1), which is attributed to the creation of quinone moieties during oxidation, and absorption at 1045 cm(-1) which is due to hydroquinone moieties.

  • 294.
    Ajjan Godoy, Fátima Nadia
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Biohybrid Polymer Electrodes for Renewable Energy Storage2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Daily and seasonally fluctuating energy supply and demand requires adequate energy storage solutions. In recent years electrochemical supercapacitors have attracted considerable attention due to their ability to both store and deliver electrical energy efficiently. Our efforts are focused on developing and optimizing sustainable organic electrode materials for supercapacitors based on renewable bioorganic materials, offering a cheap, environmentally friendly and scalable alternative to store energy. In particular, we are using the second most abundant biopolymer in nature, lignin (Lig), which is an insulating material. However, when used in combination with electroactive and conducting polymers such as polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT), the biohybrid electrodes PPy/Lig and PEDOT/Lig display significantly enhanced energy storage performance as compared to the pristine conducting polymers without the lignin. Redox cyclic voltammetry and galvanostatic charge/discharge measurements indicate that the enhanced performance is due to the additional pseudocapacitance generated by the quinone moieties in lignin. Moreover, a conjugated redoxpolymer poly(aminoanthraquinone) PAAQ, with intrinsic quinone functions and excellentstability, has been combined with lignin and PEDOT resulting in a trihybrid bioelectrode. PEDOT compensates the low conductivity of PAAQ and provides electrical pathways to the quinone groups. The electrochemically generated quinones undergo a two electron, two protonredox process within the biohybrid electrodes as revealed by FTIR spectroelectrochemistry.These remarkable features reveal the exciting potential of a full organic energy storage device with long cycle life. Therefore, supercapacitor devices were designed in symmetric or asymmetric two electrode configuration. The best electrochemical performance was achieved by the asymmetric supercapacitor based on PEDOT+Lignin/PAAQ as the positive electrode and PEDOT/PAAQ as the negative electrode. This device exhibits superior electrochemical performance and outstanding stability after 10000 charge/discharge cycles due to the synergistic effect of the two electrodes. Finally, we have characterized the response of this supercapacitor device when charged with the intermittent power supply from an organic photovoltaic module. We have designed charging/discharging conditions such that reserve power was available in the storage device at all times. This work has resulted in an inexpensive fully organic system witht he dual function of energy conversion and storage.

    Delarbeten
    1. Biopolymer hybrid electrodes for scalable electricity storage
    Öppna denna publikation i ny flik eller fönster >>Biopolymer hybrid electrodes for scalable electricity storage
    2016 (Engelska)Ingår i: Materials Horizons, ISSN 2051-6347, E-ISSN 2051-6355, Vol. 3, nr 3, s. 174-185Artikel, forskningsöversikt (Refereegranskat) Published
    Abstract [en]

    Powering the future, while maintaining a cleaner environment and a strong socioeconomic growth, is going to be one of the biggest challenges faced by mankind in the 21st century. The first step in overcoming the challenge for a sustainable future is to use energy more efficiently so that the demand for fossil fuels can be reduced drastically. The second step is a transition from the use of fossil fuels to renewable energy sources. In this sense, organic electrode materials are becoming increasingly attractive compared to inorganic electrode materials which have reached a plateau regarding performance and have severe drawbacks in terms of cost, safety and environmental friendliness. Using organic composites based on conducting polymers, such as polypyrrole, and abundant, cheap and naturally occurring biopolymers rich in quinones, such as lignin, has recently emerged as an interesting alternative. These materials, which exhibit electronic and ionic conductivity, provide challenging opportunities in the development of new charge storage materials. This review presents an overview of recent developments in organic biopolymer composite electrodes as renewable electroactive materials towards sustainable, cheap and scalable energy storage devices.

    Ort, förlag, år, upplaga, sidor
    ROYAL SOC CHEMISTRY, 2016
    Nationell ämneskategori
    Annan naturresursteknik
    Identifikatorer
    urn:nbn:se:liu:diva-128741 (URN)10.1039/c5mh00261c (DOI)000375296600002 ()
    Anmärkning

    Funding Agencies|Knut and Alice Wallenberg Foundation; Wallenberg Scholar grant

    Tillgänglig från: 2016-05-31 Skapad: 2016-05-30 Senast uppdaterad: 2017-11-30
    2. Spectroelectrochemical investigation of redox states in a polypyrrole/lignin composite electrode material
    Öppna denna publikation i ny flik eller fönster >>Spectroelectrochemical investigation of redox states in a polypyrrole/lignin composite electrode material
    Visa övriga...
    2015 (Engelska)Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 3, nr 24, s. 12927-12937Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    We report spectroelectrochemical studies to investigate the charge storage mechanism of composite polypyrrole/lignin electrodes. Renewable bioorganic electrode materials were produced by electropolymerization of pyrrole in the presence of a water-soluble lignin derivative acting as a dopant. The resulting composite exhibited enhanced charge storage abilities due to a lignin-based faradaic process, which was expressed after repeated electrochemical redox of the material. The in situ FTIR spectroelectrochemistry results show the formation of quinone groups, and reversible oxidation-reduction of these groups during charge-discharge experiments in the electrode materials. The most significant IR bands include carbonyl absorption near 1705 cm(-1), which is attributed to the creation of quinone moieties during oxidation, and absorption at 1045 cm(-1) which is due to hydroquinone moieties.

    Ort, förlag, år, upplaga, sidor
    ROYAL SOC CHEMISTRY, 2015
    Nationell ämneskategori
    Materialkemi
    Identifikatorer
    urn:nbn:se:liu:diva-120069 (URN)10.1039/c5ta00788g (DOI)000356022800044 ()
    Anmärkning

    Funding Agencies|Knut and Alice Wallenberg foundation; Marie Curie network Renaissance; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]

    Tillgänglig från: 2015-07-06 Skapad: 2015-07-06 Senast uppdaterad: 2017-12-04
    3. High performance PEDOT/lignin biopolymer composites for electrochemical supercapacitors
    Öppna denna publikation i ny flik eller fönster >>High performance PEDOT/lignin biopolymer composites for electrochemical supercapacitors
    Visa övriga...
    2016 (Engelska)Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 4, nr 5, s. 1838-1847Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Developing sustainable organic electrode materials for energy storage applications is an urgent task. We present a promising candidate based on the use of lignin, the second most abundant biopolymer in nature. This polymer is combined with a conducting polymer, where lignin as a polyanion can behave both as a dopant and surfactant. The synthesis of PEDOT/Lig biocomposites by both oxidative chemical and electrochemical polymerization of EDOT in the presence of lignin sulfonate is presented. The characterization of PEDOT/Lig was performed by UV-Vis-NIR spectroscopy, FTIR infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, cyclic voltammetry and galvanostatic charge-discharge. PEDOT doped with lignin doubles the specific capacitance (170.4 F g(-1)) compared to reference PEDOT electrodes (80.4 F g(-1)). The enhanced energy storage performance is a consequence of the additional pseudocapacitance generated by the quinone moieties in lignin, which give rise to faradaic reactions. Furthermore PEDOT/Lig is a highly stable biocomposite, retaining about 83% of its electroactivity after 1000 charge/discharge cycles. These results illustrate that the redox doping strategy is a facile and straightforward approach to improve the electroactive performance of PEDOT.

    Ort, förlag, år, upplaga, sidor
    ROYAL SOC CHEMISTRY, 2016
    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-125323 (URN)10.1039/c5ta10096h (DOI)000368839200035 ()
    Anmärkning

    Funding Agencies|Power Papers project from the Knut and Alice Wallenberg foundation; Wallenberg Scholar grant from the Knut and Alice Wallenberg foundation; Marie Curie network Renaissance (NA); European Research Council by Starting Grant Innovative Polymers for Energy Storage (iPes) [306250]; Basque Government

    Tillgänglig från: 2016-02-23 Skapad: 2016-02-19 Senast uppdaterad: 2017-11-30
  • 295.
    Ajma, Muhammad
    et al.
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Furdek, Marija
    School of Information and Communication Technology, KTH Royal Institute of Technology, Stockholm, Sweden / Faculty of Electrical Engineering and Computing, Dept. of Telecommunications, University of Zagreb, Croatia.
    Monti, Paolo
    School of Information and Communication Technology, KTH Royal Institute of Technology, Stockholm, Sweden.
    Wosinska, Lena
    School of Information and Communication Technology, KTH Royal Institute of Technology, Stockholm, Sweden.
    Forchheimer, Robert
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Dynamic provisioning utilizing redundant modules in elastic optical networks based on architecture on demand nodes2014Ingår i: European Conference on Optical Communication (ECOC), 2014, IEEE , 2014, s. 1-3Konferensbidrag (Refereegranskat)
    Abstract [en]

    Survivable synthetic ROADMs are equipped with redundant switching modules to support failure recovery. The paper proposes a dynamic connection provisioning strategy which exploits these idle redundant modules to provision regular traffic resulting in a substantial improvement in the blocking performance.

  • 296.
    Ajmal, Muhammad
    et al.
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Cavdar, Cicek
    Royal Institute of Technology, KTH, Stockholm, Sweden.
    Wosinska, Lena
    Royal Institute of Technology, KTH, Stockholm, Sweden.
    Forchheimer, Robert
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Trading Quality of Transmission for Improved Blocking Performance in All-Optical Networks2013Ingår i: Asia Communications and Photonics Conference 2013, 2013, s. AF4E.5-Konferensbidrag (Refereegranskat)
    Abstract [en]

    We propose a connection provisioning strategy in dynamic all-optical networks, which exploit the possibility to allow a tolerable signal quality degradation during a small fraction of holding-time resulting in a significant improvement of blocking performance.

  • 297.
    Ajmal, Muhammad
    et al.
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Furdek, Marija
    Royal Institute of Technology, KTH, Stockholm, Sweden / Dept. of Telecommunications, University of Zagreb, Croatia.
    Monti, Paolo
    Royal Institute of Technology, KTH, Stockholm, Sweden.
    Wosinska, Lena
    Royal Institute of Technology, KTH, Stockholm, Sweden.
    Forchheimer, Robert
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    An Optimization Model for Dynamic Bulk Provisioning in Elastic Optical Networks2014Ingår i: Asia Communications and Photonics Conference 2014, Optics Info Base, Optical Society of America, 2014, s. AF3E.6-Konferensbidrag (Refereegranskat)
    Abstract [en]

    We investigate benefits of setup-delay tolerance in elastic optical networks and propose an optimization model for dynamic and concurrent connection provisioning. Simulation shows that the proposed strategy offers significant improvement of the network blocking performance.

  • 298.
    Ajmal, Muhammad
    et al.
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Zervas, Georgios
    High-Performance Networks Group, University of Bristol, UK.
    Saridis, George
    High-Performance Networks Group, University of Bristol, UK.
    Salas, Emilio H.
    High-Performance Networks Group, University of Bristol, UK.
    Simeonidou, Dimitra
    High-Performance Networks Group, University of Bristol, UK.
    Forchheimer, Robert
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Flexible and Synthetic SDM Networks with Multi-core-Fibers Implemented by Programmable ROADMs2014Ingår i: Proceedings of European Conference on Optical Communication ECOC2014, Cannes, France, September 21-25 September 2014, IEEE , 2014, s. 1-3Konferensbidrag (Refereegranskat)
    Abstract [en]

    This study looks into network planning issues for synthetic MCF-based SDM networks implemented through programmable ROADMs. The results show that significant savings in switching modules and energy can be attained by exploiting the flexibility inherent in programmable ROADM through a proper network design.

  • 299.
    Akhlaq, Faisal
    et al.
    Linköpings universitet, Institutionen för datavetenskap.
    Loganathan, Sumathi
    Linköpings universitet, Institutionen för datavetenskap.
    Assembler Generator and Cycle-Accurate Simulator Generator for NoGAP2010Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    System-on-Chip is increasingly built using ASIP(Application  Specific Instruction set Processor) due to the flexibility and efficiency obtained from ASIPs. NoGAP (Novel Generator of Accelerator and Processor framework) is an innovative approach for  ASIP design, which provides the advantage of both ADL (Architecture  Description Language) and HDL (Hardware Description Language) to the  designer.

    For the processors designed using NoGAP, software tools need to be automatically generated, to aid the  designer in programming and verifying the processor. As part of the master thesis work, we have developed two generators namely Assembler generator and Cycle-Accurate Simulator generator for NoGAP using C++. The Assembler generator automatically generates an assembler, which is used to convert the assembly code written by a programmer into relocatable binary code. The Cycle-Accurate Simulator generator automatically generates a cycle-accurate simulator to model the behavior of the designed processor. Both these generators are static, and can be used to generate the tools for any processor created using NoGAP.

    In this report, we have detailed the concepts behind the generators,and the implementation details of the generators. We have listed the results obtained from running assembler and cycle-accurate simulator on a test processor created using NoGAP.

  • 300.
    Akhter Feroz, Raisin
    Linköpings universitet, Institutionen för tema, Tema vatten i natur och samhälle. Linköpings universitet, Filosofiska fakulteten.
    Climate Change Vulnerability Assessment for Sustainable Urban Development: A Study on Slum Population of Kota, India2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The urban centres are becoming more vulnerable to climate change because of the rapid urbanization and the inequality of urban development. This study assesses the urban vulnerability in an integrated approach focusing the slum people as the targeted group. The slum people are severely exposed to climate risks in terms of city‟s overall development. The negative indications of the indicators of person‟s vulnerability represent their high sensitivity to the adverse impact of climate change. The determinants of adaptive capacity also confirm that the slum people are more vulnerable to climate change with having lower adaptive capacity; though, the city is possessing high development indexes. In this context, an institutional structure is developed to build multi-level urban climate governance with the involvement of all relevant stakeholders based on the case study and literature review to integrate the vulnerable group in development planning for climate change adaptation.

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