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Colleague dr. Jan Willem Foppen (1965–2024) passed away

A life dedicated to groundwater contaminant transport research & education On June 24 th , 2024 Jan Willem Foppen passed away at the age of 58. Jan Willem was a widely recognized and appreciated specialist on groundwater contaminant transport, especially of colloids, an excellent and beloved lecturer and mentor, and a dear friend to many in the hydrology community. Jan Willem received his education at Vrije Universiteit (VU) Amsterdam and obtained his MSc-degree in hydrogeology. Until 1998 he worked at the VU and Institute for Applied Geosciences, TNO, on a wide variety of hydrological projects. In 1995, he stepped into the life-changing adventure as a resident hydrogeologist working in Yemen. Here, he was responsible for the drinking water supply in the Sana’a region. His multi-talent was shown here: he organized, planned and performed the fieldwork, data collection, and groundwater modelling all by himself. He was deeply concerned about the overexploitation of the groundwater resources (mainly due to qat irrigation) and the fast decline in groundwater quality. He loved working in Yemen. Therefore, in 1998, he joined IHE Delft and stayed until 2000 in Yemen as a resident advisor for Sana’a University. He established the Water & Environment Centre and worked on the MSc program on Water and Environment. Back in Delft, he joined the hydrology group of IHE and ran a wide range of training and expert panel projects in the Middle East region. In this period, his enthusiasm for science grew, and he started to work on E. coli transport in groundwater systems. Although the application focused on the Sana’a basin, he wanted to understand the behavior of E. coli in saturated porous media fundamentally. He performed numerous laboratory experiments and often managed to stay through the night in the IHE laboratory. This resulted in his very well received PhD in 2007. Jan Willem was an experienced educator. He developed, coordinated and taught a wide variety of courses, workshops and MSc programs. He was passionate about bringing students to the field, especially to Southern France, and confronted them with hydrology in practice. Hydro(geo)logy was not a science that could be taught in class only; this was his motto. He supported active learning and self-efficacy of students to achieve goals by believing in themselves. He had the capacity to let students and colleagues grow! Jan Willem continued cutting edge, creative research on colloid transport in porous media with MSc students and PhD students. He wanted to understand the underlying complex processes in particle transport, which made him shift his focus from water resources to more fundamental research. It made him move to TUDelft part-time in 2021 and full-time in 2023. Here, he managed to bridge disciplines, pro-actively stepped forward to assist with fieldwork and excursions and helped many of the younger and experienced staff alike with project proposals, research designs, interpretation of experimental results and manuscript writing. He was an excellent writer, a master in writing lean, clean and to-the-point scientific articles. He rigorously deleted speculations or unsupported ideas. Those were for new lab experiments. Jan Willem was a dedicated scientist with the highest standards of research and scholarship. He expected to give the best one could: for himself, his colleagues and his students. Determined, driven, direct, and opportunistic, Jan Willem would give a lot to his students and expect no less in return, but he always could retract and support you as much as needed. We want to express our deepest condolences to his family and friends, and we wish them strength in these difficult times. We will dearly miss Jan Willem and his boundless enthusiasm, scientific knowledge, positive attitude and humour. With Jan Willem, we have lost a wise, bold, helpful, hard-working, genuine, creative, and super honest 58-year young mentor, colleague and friend. Profile Jan Willem Foppen (1965) received his M.Sc. degree in Hydrogeology from the VU University in Amsterdam in 1990. He worked for Natuurmonumenten, Dienst Grondwaterverkenning TNO, the Institute of Applied Geosciences of TNO, and since 1998 for IHE Delft. Intrigued by poor groundwater health conditions in various developing countries, Foppen focused on the transport of the fecal indicator organism Escherichia coli in saturated porous media, whereby the aim was to extend the colloid filtration theory. Over the years, his interest focused more on the transport of colloids in groundwater and surface waters. Since 2016, he worked on silica DNA tracers. In search of new tracer substances to identify hydrologic processes, Foppen and his team used synthetic DNA in groundwater and surface water injection experiments. Synthetic DNA is a small piece of 'organic matter', 100% natural, and completely harmless. Detection of these synthetic DNA molecules is carried out by the polymerase chain reaction (PCR), a method widely used in molecular microbiology, biomedical research, forensic diagnostics, etc. Besides the transport of bacteria and silica DNA tracers, his research interests include water and sanitation in slums in Sub-Saharan Africa. In 2023, he arrived at TU Delft. His research interests address environmental water quality issues with a focus on: artificial DNA, either free or encapsulated, as a marker to study mass transport processes in hydrology; groundwater safety and the transport of bacteria and viruses in groundwater and surface water systems; fate of colloids, like plastics and engineered nanomaterials in environmental waters; water and sanitation in slums in sub-Saharan Africa (T-GroUP website, SCUSA website). Since March 2024, he had the ius promovendi.

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Papers Daan Bos en Noah Gooijer vallen in de prijzen op International System Dynamics Conference

Daan Bos en Noah Gooijer (beiden oud EPA-student) hebben de honourable mention Dana Meadows Award ontvangen tijdens de International System Dynamics Conference in Bergen. De prijs erkent hoogwaardig student onderzoek op het gebied van systeemdynamica. Systeemdenken in mentale gezondheidszorg Daan deed onderzoek naar systeemdenken in de mentale gezondheidszorg. Alcoholmisbruik is wereldwijd een groot gezondheidsprobleem en leidt tot veel ziekte en sterfte. In Nederland is er een lichte daling in overmatig alcoholgebruik, maar toch heeft ongeveer 20% van de bevolking nog steeds een alcoholverslaving. Dit zorgt voor veel druk op de geestelijke gezondheidszorg, nu en in de toekomst. Het paper beschrijft onderzoek dat met behulp van Group Model Building de meningen van experts over alcoholverslaving in de zorg in kaart brengt en voegt ze samen. De resultaten laten zien dat experts vaak alleen naar hun eigen deel van het probleem kijken en het overzicht over het hele systeem missen. De studie benadrukt dat het betrekken van heterogene groepen experts kan helpen bij het vinden van oplossingen voor een duurzame gezondheidszorg. Lees de samenvatting van zijn thesis. Systeemdenken bij brugonderhoud Noah’s paper introduceert een nieuwe manier om fysieke infrastructuur te modelleren met een Entity-based System Dynamics aanpak. Deze nieuwe methode maakt het mogelijk om complexe netwerken op systeemniveau te analyseren, terwijl er ook ruimte is om kleinere onderdelen van het systeem gedetailleerd te modelleren. Het paper laat zien hoe verschillende strategieën voor brugonderhoud invloed hebben op het efficiënt inzetten van middelen zoals personeel en materiaal. De resultaten tonen aan dat het samenvoegen van onderhoudsprojecten kan zorgen voor een efficiënter gebruik van middelen en een beter voorspelbare inzet van onderhoudscapaciteit. Lees Noah’s thesis . Over de International System Dynamics conference De International System Dynamics Conference brengt experts, professionals en studenten samen om ideeën uit te wisselen, praktijkvoorbeelden te tonen en buitengewone prestaties in het vakgebied te vieren. Elk jaar erkent de System Dynamics Society uitzonderlijke bijdragen met verschillende prijzen. Lees meer . Daan Bos tijdens ontvangst prijs. Noah Gooijer

Bipolar membranes for intrinsically stable and scalable CO2 electrolysis

The energy transition requires technology to supply sustainable carbon-based chemicals for hard-to-abate sectors such as long-distance transport and plastic manufacturing. These necessary hydrocarbon chemicals and fuels, responsible for 10-20% of the global greenhouse gas emissions, can be produced sustainably by the electrolysis of captured CO 2 using renewable electricity. Currently, the state-of-the-art CO 2 electrolyzers employ anion exchange membranes (AEMs) to facilitate the transport of hydroxide ions from the cathode to the anode. However, CO 2 is crossing the membrane as well, resulting in a loss of reactant and unfavourable anode conditions which necessitates the use of scarce anode materials. Bipolar membranes (BPMs) offer an alternative that addresses the problem of CO 2 crossover but still requires research to match the product selectivity of AEM-based systems. Our perspective, a collaboration between groups of David Vermaas, Tom Burdyny and Marc Koper, published in Nature Energy, assesses the potential of BPMs for CO 2 electrolysis by looking at CO 2 utilization, energy consumption, and strategies to improve the product selectivity. Abstract CO 2 electrolysis allows the sustainable production of carbon-based fuels and chemicals. However, state-of-the-art CO 2 electrolysers employing anion exchange membranes (AEMs) suffer from (bi)carbonate crossover, causing low CO 2 utilization and limiting anode choices to those based on precious metals. Here we argue that bipolar membranes (BPMs) could become the primary option for intrinsically stable and efficient CO 2 electrolysis without the use of scarce metals. Although both reverse- and forward-bias BPMs can inhibit CO 2 crossover, forward-bias BPMs fail to solve the rare-earth metals requirement at the anode. Unfortunately, reverse-bias BPM systems presently exhibit comparatively lower Faradaic efficiencies and higher cell voltages than AEM-based systems. We argue that these performance challenges can be overcome by focusing research on optimizing the catalyst, reaction microenvironment and alkali cation availability. Furthermore, BPMs can be improved by using thinner layers and a suitable water dissociation catalyst, thus alleviating core remaining challenges in CO 2 electrolysis to bring this technology to the industrial scale. Go to the publication Kostadin Petrov Christel Koopman David Vermaas Tom Burdyny Siddharta Subramanian

Understanding the learning process: machine learning and computational chemistry for hydrogenation

Machine learning is being mentioned all around, but can it be applied to modelling homogeneous catalysis? Researchers from TU Delft together with Janssen Pharmaceuticals published an extensive study accompanied by one of the biggest datasets on rhodium-catalyzed hydrogenation in Chemical Science trying to answer this question. Adarsh Kalikadien Evgeny Pidko For more than half a century, Rhodium-based catalysts have been used to produce chiral molecules via the asymmetric hydrogenation of prochiral olefins. The importance of this transformation was acknowledged by a Nobel prize given to Noyori and Knowles for their contributions in this field. Nowadays, asymmetric hydrogenation catalysts are widely used in the pharmaceutical industry, numerous chiral ligands are available to tackle a wide range of prochiral substrates and the reaction mechanism has been extensively studied. Consequently, one would expect that finding the best catalyst for the asymmetric hydrogenation of a new substrate is a trivial task. Unfortunately, this is not the case and a tedious and costly experimental screening is still needed. Adarsh Kalikadien and Evgeny Pidko from TU Delft together with experts in high-throughput-experimentation, data science and computational chemistry from Janssen Pharmaceutica in Belgium decided to investigate whether a well-trained machine could do the job. To their surprise, the machine was actually not able to learn as much as they expected. The idea was to set up a simple model reaction with a well-known rhodium catalyst. Based on the experimental data generated by the high-throughput experimentation team of Janssen, a computational dataset was built to which multiple machine learning models were applied. “We digitalized the 192 catalyst structures and represented them with features of various levels of complexity for the machine learning models,” says Kalikadien, a PhD student in Pidko’s group. "The interesting thing was that all the simpler models, including the random model, showed similar performances as the expensive variant, which intrigued us. It turned out to be an early indication that the machine was not really learning anything useful.” "One of our conclusions was, when tested more extensively, that for an out-of-domain modeling approach, it doesn't matter what representation you put in”. Nevertheless, although the team was not able to build an accurate model, their study was worth publishing. The publication process went relatively smoothly. “Although the first journal we contacted rejected our submission as too specialized, the high-impact journal Chemical Science saw the value of this work. Not many researchers are interested in just seeing the R2 value of a model and then having no possibility to use it, they are probably interested in an in-depth analysis like ours. So we were able to submit our data, code and even interactive figures there for everyone to use.” At the moment there is a big incentive for publishing negative data in order to help the community to assess the true added value of machine learning, since models trained on mainly positive results tend to become very biased. "We made everything open source," says Kalikadien. "Not only is all the data accessible, but we also offer the code including packages and instructions, so that anyone who is interested can do the same type of research." In this way, they have published one of the largest datasets of a certain type of hydrogenation reaction. What's next? "Our representation of the catalyst wasn't as meaningful for the machine learning models as we had hoped, so we are now looking for a representation that may be less simplified but still as simple as possible," says Kalikadien. "Creating a digital representation of your catalyst should not cost way more money than running the actual experiment, so we are trying to incorporate more information from the reaction mechanism into the model without making it too extensive. A more dynamic and hopefully more informative version of the representation." Read the publication Adarsh Kalikadien, Cecile Valsecchi, Robbert van Putten, Tor Maes, Mikko Muuronen, Natalia Dyubankova, Laurent Lefort and Evgeny A. Pidko

Start jij dit jaar je studie in Delft? ‘Discover your X’ tijdens de OWee en IP!

Wat tof, jij gaat aan de TU Delft studeren! Dan neem je vast ook deel aan de OWee of IP. Tijdens deze week ontdek je alles over de TU Delft, Delft zelf én natuurlijk wat er te doen is buiten je studie. Wil jij in Delft sporten? Jezelf creatief uiten? Helemaal ontspannen? Nieuwe mensen ontmoeten? Of af en toe een te gek evenement bijwonen? We zien jou graag tijdens de infomarkt én natuurlijk de Activity Market bij X! Op maandag 19 augustus staan we op de infomarkt in Delft. Hopelijk kunnen we daar alvast kennismaken! Avondprogramma Vanaf zondag 18 augustus t/m donderdag 22 augustus kun je alvast kennismaken met X door de evenementen uit ons rustige avondprogramma te bezoeken. Klik hier voor de agenda. Activity Market | 21 augustus Op woensdag 21 augustus vindt bij X de Activity Market plaats voor alle nieuwe en eerstejaars studenten. Je maakt hier kennis met de faciliteiten van X, de sport- & en cultuurverenigingen en alles wat X te bieden heeft op het gebied van sport, cultuur, kunst, lifestyle, games en eten en drinken. Volg ons alvast op Instagram voor een eerste sneak peek van X en de Activity Market! *Er worden foto's gemaakt op de Activity Market. Meer info over ons fotografiebeleid bij X vind je in de algemene voorwaarden. Beschikbaarheid X voor huidige X-leden X-leden kunnen nog steeds meedoen met het beschikbare aanbod, maar houd rekening met extra drukte. Zo kunnen de nieuwe studenten dit jaar ook een kijkje nemen in de Fitness op de Activity market tussen 11:00 en 15:00. Check de beschikbare lessen en waar ze komende week plaatsvinden in het rooster.

Opening van het academisch jaar 2024-2025 op 2 september

Vier met ons de opening van het academisch jaar! Je bent van harte uitgenodigd om op maandag 2 september aanwezig te zijn bij de opening van het Academisch Jaar 2024-2025 van de TU Delft. Met het thema 'Engineering the Future' kijken we dit jaar naar de bouwstenen van onze duurzame toekomst. Mobiliteit, voedselvoorziening, gezondheidszorg, energievoorziening en de manier waarop we grondstoffen gebruiken: ze zullen allemaal drastisch veranderen in deze eeuw. Aan de TU Delft kunnen we deze transities helpen vormgeven. Wat we hier doen kan invloed hebben op hoe bedrijven en eindgebruikers zich gedragen. Neem onze smartphones, waarvan het meeste goud en lithium na een paar jaar nog steeds op de vuilnisbelt belandt. Als je ze vanaf het begin anders ontwerpt, kun je uiteindelijk 'nul afval' bereiken - en dit is slechts één voorbeeld. Michiel Langezaal, alumnus en CEO van FastNed, het bedrijf dat een netwerk van snellaadpunten bouwt langs de snelwegen van Europa, is te gast. We praten met Dream Team Epoch, dat AI wil gebruiken om bij te dragen aan de Sustainable Development Goals van de Verenigde Naties. We verwelkomen ook Irek Roslon, alumnus en oprichter van SoundCell, de startup die een screening ontwikkelt waarmee artsen razendsnel de juiste antibiotica voor patiënten kunnen kiezen. Zij zullen het hebben over hun weg naar de toekomst, de bouwstenen die ze nodig hebben en de obstakels waar ze tegenaan lopen. Hoe ze hun eigen en onze toekomst vormgeven en met wie ze samenwerken. Muziek en dans maken ook deel uit van deze feestelijke bijeenkomst. En aan het eind heffen we met z'n allen het glas op het nieuwe academische jaar! Klik hier om je aan te melden.