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Melis Duyar

Dr. Melis Duyar | University of Surrey Return to homepage Designing dual function materials for integrated carbon dioxide capture and utilisation Carbon dioxide capture and utilisation (CCU) technologies will play an essential role in decarbonising all sectors to reach a net zero emission future. In particular there is an urgent need to replace fossil derived carbon in the chemical industry as well as in fuels supplied to “hard-to-decarbonise” sectors such as transportation and residential heating. Dual function materials (DFMs) for integrated CCU are materials designed with both adsorbent and catalytic capabilities (hence “dual function”) that can capture and subsequently directly convert dilute streams of CO 2 (from stationary emissions or the atmospheric air) to useful chemicals. In a typical cycle of operation, the DFMs are first exposed to a source of CO 2 to achieve capture, then switched to a stream of co-reactant such as hydrogen or hydrocarbons to achieve the in-situ conversion of captured CO 2 . The chemical transformation of captured CO 2 regenerates the adsorbent while releasing a concentrated stream of desired end product. In combining CO 2 capture and utilisation, DFMs can achieve unique synergies that can improve energy efficiency. For example, exothermic hydrogenations of CO 2 such as the methanation reaction can supply heat that then drives CO 2 on adsorbent sites to spill over to catalytic sites during DFM operation. This allows reaction heat to be directly used in the energy intensive process of sorbent regeneration, while maintaining isothermal conditions to promote CO 2 conversion on catalytic sites. This seminar will discuss approaches to develop novel adsorbent materials for CO 2 capture, catalytic materials for the production of sustainable chemicals and present strategies to effectively combine these approaches to yield an integrated CCU system. A rational design approach based on fundamental understanding of structure-function relationships is needed to accelerate materials discovery for CCU in a diverse set of scenarios, and recent developments in this area will also be presented. Biography Dr. Melis Duyar is Senior Lecturer in the School of Chemistry and Chemical Engineering at the University of Surrey. She has a research background in heterogeneous catalysis for energy and environmental applications. Her current research interests include engineering dynamic catalytic systems for the direct utilization of CO 2 in any emissions source, the catalytic upcycling of plastics waste and the sustainable synthesis and use of ammonia. Dr. Duyar received her B.Sc. (2012) in Chemical and Biological Engineering from Koç University. She obtained her M.S. (2013) and Ph.D. (2015) in Earth and Environmental Engineering from Columbia University and conducted post-doctoral research (2015-2017) in the Chemical Engineering Department at Stanford University. Prior to her appointment at the University of Surrey (2019), she worked at the US Department of Energy’s SLAC National Accelerator Laboratory as Associate Staff Scientist at the SUNCAT Center for Interface Science and Catalysis and was also Lecturer of Chemical Engineering at Stanford University (2017-2019).

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SciVal is a bibliometric tool that can be used to analyse and visualize the positioning of research of individuals, groups and institutes. As a researcher, you can use SciVal for example to create evaluation reports, identify a publication strategy, and to find new collaborations. What does Scival provide? SciVal uses the Scopus database and provides publication information and metrics of over 10,000 research institutions, countries and individual researchers. You can define your own publication sets, groups or research areas by using keywords, importing publications from Scopus for example. You can also collect and group names of colleagues or collaborators to analyse group performances. Log in to SciVal Use Overview to get a high-level overview of the research performance of TU Delft, other institutions, countries and groups of researchers. Use Benchmarking to compare and benchmark TU Delft with other institutions, researchers and groups of researchers using a variety of metrics. Use the Collaboration module to explore the collaboration network of both TU Delft and other institutions. Explore Trends to get the current scientific trends to determine a new research strategy, and to find collaboration opportunities and rising stars. How to get started with SciVal Read SciVal at a glance for a quick overview of how it works and access SciVal to explore the tool. Do you have questions or need help or practical examples? Consult the FAQ and the ever growing number of SciVal use cases or email library@tudelft.nl . Share your feedback If you have any feedback, ideas, suggestions etc. after using SciVal, please send these to library@tudelft.nl . Your feedback, is highly appreciated as it helps us improve our services and support as a Library. Thank you.

Prof.dr. Laurens Siebbeles

Laurens Siebbeles (1963) is head of the section Optoelectronic Materials in the Chemical Engineering Department at TU Delft, (3 PI's, 5 technicians, ~20 PhD students/postdocs). The section has a worldwide unique infrastructure with production of excitons/charges by laser or high-energy electron pulses, and detection by time-resolved optical, microwave or THz conductivity techniques. He pairs experimental research with theory of charge/exciton dynamics in materials with potential (opto)electronic applications. Experimental and theoretical studies are carried out in collaboration with numerous academic groups worldwide and with industry, most notably Toyota Motor Europe in Brussels, Belgium. He publishes the results in international peer reviewed journals and via (invited) oral presentations at (international) conferences, universities or research institutes. Some results have been highlighted in other scientific journals, (inter)national newspapers and other popular media/websites. The research of Siebbeles has been funded by the Netherlands Organisation for Scientific Research (NWO, FOM, STW), the European Union, the Deutsche Forschungs Gemeinschaft and Toyota Motor Europe. In 2004 he received a VICI grant from NWO; a prestigious grant of 1250 k€ for PI's who have demonstrated their ability to develop a new line of research and act as mentor for young researchers. The grant was complemented by 500 k€ from TU Delft and used to develop a femtosecond laser facility and picosecond pulsed high-energy electron accelerator. In 2016 he was awarded an NWO-TOP grant of 800 k€, offering outstanding researchers the possibility to renew their research. He uses this grant to study excitons and charge carriers at high density, including the formation of electron-hole Cooper pairs (in collaboration with Vanmaekelbergh and Stoof from Utrecht). On a regular basis Siebbeles is (co-)organizer of (inter)national conferences, serves on (inter)national recruitment committees, boards for awarding research grants, etc. He has been teaching several courses for bachelor and master students at TU Delft, including classical mechanics, quantum mechanics/chemistry, spectroscopy and condensed matter physics. Since 2016 he is director of the Graduate School (for PhD students) of the Faculty of Applied Sciences at TU Delft. Curriculum Vitae Scientific education 1991 PhD degree, University of Amsterdam Thesis studies carried out in FOM Institute for Atomic and Molecular Physics (AMOLF) in Amsterdam. Thesis title: Anisotropy in the photodissociation of H2. Thesis advisor: Prof. Dr. J. Los 1986 MSc degree Chemistry, Free University Amsterdam Topics: Photolectron spectroscopy experiments on ionization of small molecules and quantum chemical electronic structure calculations. Past and present positions 2005-present Professor and head of section Optoelectronic Materials in Dept. of Chemical Engineering (TU Delft). Topics: Experiments and theory on excitons and charges in (in)organic nanomaterials, such as quantum dots, nanowires and two-dimensional materials. 2016-present Director of the Graduate School (for PhD students) of the Faculty of Applied Sciences at TU Delft. 2011-2016 Deputy Head of the Department of Chemical Engineering (TU Delft). 2001-2005 Professor and head of section Radiation Chemistry in Reactor Institute of TU Delft. Topics: Experiments and theory on excitons and charges in organic materials and interaction of high-energy radiation (electrons, positrons, muons) with matter. 2000-2001 Associate professor of Radiation Chemistry in the Reactor Institute of TU Delft. 1994-2000 Assistant professor of Radiation Chemistry in the Reactor Institute of TU Delft. Topics: Experiments and theory on excitons and charges in organic materials and interaction of high-energy radiation (electrons, positrons, muons) with matter. 1994-1994 Postdoc in FOM Institute for Atomic and Molecular Physics (AMOLF, Amsterdam) in group of Prof. Dr. W.J. van der Zande. Topic: Quantum theory on photodissociation of molecules. 1991-1994 Postdoc in Laboratoire pour l’Utilisation du Rayonnement Electromagnétique, Université de Paris Sud (Orsay, France) in group of Prof. dr. J.A. Beswick. Topics: Experiments and quantum theory on photodissociation of molecules. Awards TOP grant (2016) form the Netherlands Organisation for Scientific Research (NWO) of 800 kEuro, offering outstanding researchers the possibility to renew their research. VICI grant (2004) in the Innovational Incentives Scheme of The Netherlands Organisation for Scientific Research (NWO); prestigious grant of 1250 kEuro for senior researchers that have demonstrated their ability to develop a new line of research and act as a mentor for young researchers. Young Chemist grant (2002, NWO); grant of 230 kEuro for excellent young chemists to initiate a new research line. Antoni van Leeuwenhoek professorship (2001); honorary early promotion to full professor awarded by TU Delft to excellent, promising young scientists. Prof.dr. Laurens D.A. Siebbeles +31 (0)15 27 81800 l.d.a.siebbeles@tudelft.nl Building 58 Van der Maasweg 9 NL-2629 HZ Delft

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New LDE trainee in D&I office

Keehan Akbari has started since the beginning of September as a new LDE trainee in the Diversity and Inclusion office. What motivated him to work for the D&I office, what does he expect to achieve during this traineeship? Read the short interview below! What motivated you to pursue your LDE traineeship in Diversity and Inclusion office of the TU Delft? I completed both bachelor's and master's degrees in Cultural Anthropology and Development Sociology at Leiden University. Within these studies, my main area of interest was in themes of inclusion and diversity. After being hired as a trainee for the LDE traineeship, and discovering that one of the possible assignments belonged to the Diversity and Inclusion office, my choice was quickly made. I saw this as an excellent opportunity to put the theories I learned during my studies into practice. What specific skills or experiences do you bring to the D&I office that will help promote inclusivity on campus? I am someone who likes to connect rather than polarize, taking into account the importance of different perspectives and stakeholders. I believe that this is how one can achieve the most in fostering diversity and inclusion. You need to get multiple parties on board to get the best results. What are your main goals as you begin your role here, and how do you hope to make an impact? An important goal for me this year is to get students more involved in diversity and inclusion at the university. One way I will try to accomplish this is by contributing to the creation of D&I student teams. By establishing a D&I student team for faculties, it will be possible to deal with diversity- and inclusion-related issues that apply and relate to the specific department. How do you plan to engage with different (student) communities within the university? Since I am new to TU Delft, the first thing I need to do is expand my network here. Therefore, I am currently busy exploring the university and getting to know various stakeholders. Moreover, I intend to be in close contact with various student and study organizations to explore together how to strengthen cooperation on diversity and inclusion. Welcome to the team Keehan and we wish you lots of success with your traineeship!

Researchers from TU Delft and Cambridge University collaborate on innovative methods to combat Climate Change

For over a year and a half, researchers from TU Delft and the Cambridge University Centre for Climate Repair have worked together on groundbreaking techniques to increase the reflectivity of clouds in the fight against global warming. During a two-day meeting, the teams are discussing their progress. Researchers at Cambridge are focusing on the technical development of a system that can spray seawater, releasing tiny salt crystals into the atmosphere to brighten the clouds. The team from TU Delft, led by Prof. Dr. Ir. Herman Russchenberg, scientific director of the TU Delft Climate Action Program and professor of Atmospheric Remote Sensing, is studying the physical effects of this technique. Prof. Russchenberg emphasizes the importance of this research: "We have now taken the first steps towards developing emergency measures against climate change. If it proves necessary, we must be prepared to implement these techniques. Ideally, we wouldn't need to use them, but it's important to investigate how they work now." Prof. Dr. Ir. Stefan Aarninkhof, dean of the Faculty of Civil Engineering and Geosciences, expresses pride in the team as the first results of this unique collaboration are becoming visible. If the researchers in Delft and Cambridge can demonstrate the potential of the concept, the first small-scale experiments will responsibly begin within a year. This research has been made possible thanks to the long-term support from the Refreeze the Arctic Foundation, founded by family of TU Delft alumnus Marc Salzer Levi . Such generous contributions enable innovative and high-impact research that addresses urgent global challenges like climate change. Large donations like these enable the pursuit of innovative, high-impact research that may not otherwise be feasible, demonstrating how our collective effort and investment in science can lead to real, transformative solutions for global challenges like climate change. Climate-Action Programme

How system safety can make Machine Learning systems safer in the public sector

Machine Learning (ML), a form of AI where patterns are discovered in large amounts of data, can be very useful. It is increasingly used, for example, in chatbot Chat GPT, facial recognition, or speech software. However, there are also concerns about the use of ML systems in the public sector. How do you prevent the system from, for example, discriminating or making large-scale mistakes with negative effects on citizens? Scientists at TU Delft, including Jeroen Delfos, investigated how lessons from system safety can contribute to making ML systems safer in the public sector. “Policymakers are busy devising measures to counter the negative effects of ML. Our research shows that they can rely much more on existing concepts and theories that have already proven their value in other sectors,” says Jeroen Delfos. Jeroen Delfos Learning from other sectors In their research, the scientists used concepts from system safety and systems theory to describe the challenges of using ML systems in the public sector. Delfos: “Concepts and tools from the system safety literature are already widely used to support safety in sectors such as aviation, for example by analysing accidents with system safety methods. However, this is not yet common practice in the field of AI and ML. By applying a system-theoretical perspective, we view safety not only as a result of how the technology works, but as the result of a complex set of technical, social, and organisational factors.” The researchers interviewed professionals from the public sector to see which factors are recognized and which are still underexposed. Bias There is room for improvement to make ML systems in the public sector safer. For example, bias in data is still often seen as a technical problem, while the origin of that bias may lie far outside the technical system. Delfos: “Consider, for instance, the registration of crime. In neighbourhoods where the police patrol more frequently, logically, more crime is recorded, which leads to these areas being overrepresented in crime statistics. An ML system trained to discover patterns in these statistics will replicate or even reinforce this bias. However, the problem lies in the method of recording, not in the ML system itself.” Reducing risks According to the researchers, policymakers and civil servants involved in the development of ML systems would do well to incorporate system safety concepts. For example, it is advisable to identify in advance what kinds of accidents one wants to prevent when designing an ML system. Another lesson from system safety, for instance in aviation, is that systems tend to become more risky over time in practice, because safety becomes subordinate to efficiency as long as no accidents occur. “It is therefore important that safety remains a recurring topic in evaluations and that safety requirements are enforced,” says Delfos. Read the research paper .