21 results on '"Ulmer U"'
Search Results
2. The solar package on ISS: SOL-ACES
- Author
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Wienhold, F.G., Anders, J., Galuska, B., Klocke, U., Knothe, M., Riedel, W.J., Schmidtke, G., Singler, R., Ulmer, U., and Wolf, H.
- Published
- 2000
- Full Text
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3. Aging-related loss of the chromatin protein HMGB2 in articular cartilage is linked to reduced cellularity and osteoarthritis
- Author
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Taniguchi N, Caramés B, Ronfani L, Ulmer U, Komiya S, Lotz M., BIANCHI , MARCO EMILIO, Taniguchi, N, Caramés, B, Ronfani, L, Ulmer, U, Komiya, S, Bianchi, MARCO EMILIO, and Lotz, M.
- Published
- 2009
4. 2.4 - Advanced White cell design for investigation of ethylene using a nondispersive infrared photometer
- Author
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Eberhardt, A., primary, Wöllenstein, J., additional, Ulmer, U., additional, and Schmitt, K., additional
- Published
- 2017
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5. Phase-structural transformations in a metal hydride battery anode La1.5Nd0.5MgNi9 alloy and its electrochemical performance
- Author
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Volodin, A.A., primary, Wan, ChuBin, additional, Denys, R.V., additional, Tsirlina, G.A., additional, Tarasov, B.P., additional, Fichtner, M., additional, Ulmer, U., additional, Yu, Yingda, additional, Nwakwuo, C.C., additional, and Yartys, V.A., additional
- Published
- 2016
- Full Text
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6. Langzeit-Aerosolüberwachung mit einem kalibrierfreien, kompensierten Streulichtfotometer
- Author
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Laile, E., Zahoransky, R.A., Poss, G., Riedel, W.J., Ulmer, U., Grisar, R., and Publica
- Subjects
aerosol ,Heißgasfiltration ,Massenkonzentrationsüberwachung - Abstract
Zur Messung geringer Massenkonzentrationen und der Partikelgrößenverteilung unter hohen Druck- und Temperaturbedingungen, wie sie z.B. bei Überwachung des Gasstromes in Druckwirbelschichtfeuerungen oder in Druckkohlenstaubfeuerungen vorkommen, wird ein kompensiertes Streulichtfotometer vorgeschlagen. Streulicht- und Transmissionswerte des Partikelkollektivs werden erfasst und miteinander verknüpft . Als Vorteil dieses Mess- und Auswerteprinzips ergibt sich im Gegensatz zu konventionellen Fotometern eine weitgehende Unempfindlichkeit gegenüber Fenster-Verschmutzung und Alterung von Komponenten. Das neue Konzept ist bis etwa 900°C einsatzfähig.
- Published
- 2005
7. Die SUCCESS-Studie – Toxizitätsanalyse einer Phase III Studie mit Docetaxel und Gemcitabine in der adjuvanten Therapie des frühen Mammakarzinoms
- Author
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Genss, EM, primary, Janni, W, additional, Rack, B, additional, Sommer, H, additional, Schneeweiss, A, additional, Rezai, M, additional, Hilfrich, J, additional, Lorenz, R, additional, Tesch, H, additional, Forstbauer, H, additional, Ulmer, U, additional, Schneider, A, additional, Lichtenegger, W, additional, Beckmann, MW, additional, and Friese, K, additional
- Published
- 2008
- Full Text
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8. Abstracts from the 8th Annual Meeting of the Scientific Association of Swiss Radiation Oncology (SASRO)
- Author
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Allal, A. S., primary, Ares, C., additional, Dulguerov, P., additional, Tschanz, E., additional, Verdan, C., additional, Mhawech, P., additional, Riesterer, O., additional, Honer, M., additional, Vuong, V., additional, Jochum, W., additional, Zingg, D., additional, Bodis, S., additional, Ametamey, S., additional, Pruschy, M., additional, Inteeworn, N., additional, Ohlerth, S., additional, Höpfl, G., additional, Roos, M., additional, Wergin, M., additional, Rohrer Bley, C., additional, Gassmann, M., additional, Kaser-Hotz, B., additional, Berthou, S., additional, Aebersold, D. M., additional, Ganapathipillai, S., additional, Streit, B., additional, Stalder, D., additional, Gruber, G., additional, Greiner, R. H., additional, Zimmer, Y., additional, Lutters, G., additional, Krek, W., additional, Tenzer, A., additional, Hofstetter, B., additional, Bonny, C., additional, Azria, A., additional, Larbouret, C., additional, Cunat, S., additional, Ozsahin, M., additional, Zouhair, A., additional, Gourgou, S., additional, Martineau, P., additional, Evans, D. B., additional, Romieu, G., additional, Pujol, P., additional, Pèlegrin, A., additional, Heuberger, J., additional, Kestenholz, P., additional, Taverna, Ch., additional, Lardinois, D., additional, Jörger, M., additional, Schneiter, D., additional, Jerman, M., additional, Weder, W., additional, Stahel, R., additional, Bodis, St., additional, Vees, H., additional, Mach, N., additional, Hügli, A., additional, Balmer Majno, S., additional, Beer, K. T., additional, Friedrich, E. E., additional, Ciernik, I. F., additional, Stanek, N., additional, Taverna, C., additional, Greiner, R., additional, Mahler, F., additional, Landmann, Ch., additional, Studer, G., additional, Bernier, J., additional, Gallino, A., additional, Juelke, Peter D., additional, Hafner, Hans-Peter, additional, Jamshidi, Peiman, additional, Erne, Paul, additional, Resink, Therese Josephine, additional, Thum, Peter, additional, Notter, M., additional, Bargetzi, M., additional, Suleiman, M., additional, Luthi, J. C., additional, Bieri, S., additional, Curschmann, J., additional, Pajic, B., additional, Kranzbühler, H., additional, Lippold, B., additional, Ueltschi, G., additional, Bonetti, M., additional, Nasi, M. L., additional, Price, K. N., additional, Castiglione-Gertsch, M., additional, Rudenstam, C.-M., additional, Holmberg, S. B., additional, Lindtner, J., additional, Gol-ouh, R., additional, Collins, J., additional, Crivellari, D., additional, Carbone, A., additional, Thürlimann, B., additional, Simoncini, E., additional, Fey, M. F., additional, Gelber, R. D., additional, Coates, A. S., additional, Goldhirsch, A., additional, Jeanneret Sozzi, W., additional, Kramar, A., additional, Mirimanoff, R. O., additional, Azria, D., additional, Taussky, D., additional, Becker, M., additional, Kranzbuehler, H., additional, Weitzel, M., additional, Bortoluzzi, L., additional, Behrensmeier, F., additional, Isaak, B., additional, Pasche, P., additional, Luthi, F., additional, Weber, D. C., additional, Lomax, A. J., additional, Rutz, H. P., additional, Pedroni, E. S., additional, Verwey, J., additional, Goitein, G., additional, Timmermann, B., additional, Lomax, A., additional, Bolsi, A., additional, Weber, D., additional, Bentzen, S. M., additional, Khalil, A. A., additional, Saunders, M. I., additional, Horiot, J. C., additional, Van den Bogaert, W., additional, Cummings, B. J., additional, Dische, S., additional, Slosman, D. O., additional, Kebdani, T., additional, Allaoua, M., additional, Stadelmann, O., additional, Stupp, R., additional, Pica, A., additional, Dubois, J. B., additional, Oehler, C., additional, Ulmer, U., additional, Lütolf, U. M., additional, Huser, M., additional, Burger, C., additional, Szekely, G., additional, Davis, J. B., additional, Gervaz, P., additional, Gertsch, P., additional, Morel, Ph., additional, Roth, A. D., additional, Zenklusen, H., additional, Schott, A., additional, Curti, G., additional, Schefer, H., additional, Kolotas, C., additional, Thalmann, G., additional, Vetterli, D., additional, Kemmerling, L., additional, Mini, R., additional, Rouzaud, M., additional, Nouet, P., additional, Mollà, M., additional, Escudé, L., additional, Miralbell, R., additional, Beer, K., additional, von Briel, C., additional, Jichlinski, P., additional, Guillou, L., additional, Fogliata, A., additional, Nicolini, G., additional, Cozzi, L., additional, Hafner, H. P., additional, Hueber, P., additional, Szczerba, D., additional, Born, E. J., additional, Dipasquale, G., additional, Jargy, C., additional, Munier, F., additional, Balmer, A., additional, Do, H. P., additional, Pasche, G., additional, Wang, H., additional, Moeckli, R., additional, Boehringer, T., additional, Coray, A., additional, Lin, S., additional, Pedroni, E., additional, Rutz, H., additional, Baumert, B. G., additional, Norton, I. A., additional, Schoenmaker, E., additional, Krayenbühl, J., additional, Bründler, M.-A., additional, Allemann, K., additional, Laluhovà, D., additional, Collen, T., additional, Coucke, P., additional, Ries, G., additional, Rufibach, K., additional, Huguenin, P., additional, Abdou, M., additional, Girardet, C., additional, Vees, H. J., additional, Bigler, R., additional, Özsoy, O., additional, Bouville, S., additional, Corminboeuf, F., additional, Betz, M., additional, Matzinger, O., additional, Tebeu, P., additional, Popowski, Y., additional, Verkooijen, H., additional, Bouchardy, C., additional, Ludicke, F., additional, Usel, M., additional, Major, A., additional, Merçay, A., additional, Pache, G., additional, Bulling, S., additional, Bressan, S., additional, Valley, J. F., additional, Motta, M., additional, Presilla, S., additional, Richetti, A., additional, Franzetti, A., additional, and Pesce, G., additional
- Published
- 2004
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9. Cultural differences in simulation debriefing: A qualitative analysis.
- Author
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Rana SC, Francis U, Zavi L, Ella S, Honein-Abou Haidar G, and Peter D
- Abstract
Context: Simulation is a social practice impacted by norms, values, and beliefs. We seek to explore the relationship between cultural factors and participant behaviour patterns as perceived by debriefers during healthcare simulation debriefings. Our research question focuses on elucidating factors that influence debreifing dynamics between and among debriefers and learners according to Hofstede's cultural dimension: the Power Distance Index., Methods and Materials: The study employed inductive qualitative analysis following Braun and Clark's 6-step approach to explore debriefers' perceived barriers to discussing non-technical skills including closed-loop communication, situational awareness, and cultural aspects of healthcare simulation debriefing. This study is a complementation to previously published quantitative paper, the qualitative findings are derived from the third section of the interview guide developed by the authors which focused on aspects of the debriefing such as debriefers' perceptions of participant familiarity with non-technical skills and cultural sensitivity., Findings: The responses of 57 debriefers from 26 countries were analysed; 36 (64%) of whom practiced simulation in low power distance index (PDI) countries and 31 (36%) practiced in high PDI countries. We identified three major themes: I. Group dynamics, encompassing challenges of hierarchy, 'speaking up', fear of 'losing face' and 'judgement'. II. Conceptual clarity about debriefing medical/technical content and the challenges of 'language' and III. Institutional 'skepticism' toward simulation as a relatively new method of teaching in many parts of the world ., Insights: The findings confirm the social nature of simulation debriefings, where the interactions are guided by motivations and rules, and where more variability can be found within a culture than between cultures. Acknowledging these differences could lead to cultivating new integrative perspectives for all levels of the healthcare system., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.The authors have no conflicting interest to declare., (©2023PublishedbyElsevierLtd.)
- Published
- 2023
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10. Solar Urea: Towards a Sustainable Fertilizer Industry.
- Author
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Xia M, Mao C, Gu A, Tountas AA, Qiu C, Wood TE, Li YF, Ulmer U, Xu Y, Viasus CJ, Ye J, Qian C, and Ozin G
- Abstract
Urea, an agricultural fertilizer, nourishes humanity. The century-old Bosch-Meiser process provides the world's urea. It is multi-step, consumes enormous amounts of non-renewable energy, and has a large CO
2 footprint. Thus, developing an eco-friendly synthesis for urea is a priority. Herein we report a single-step Pd/LTA-3A catalyzed synthesis of urea from CO2 and NH3 under ambient conditions powered solely by solar energy. Pd nanoparticles serve the dual function of catalyzing the dissociation of NH3 and providing the photothermal driving force for urea formation, while the absorption capacity of LTA-3A removes by-product H2 O to shift the equilibrium towards urea production. The solar urea conversion rate from NH3 and CO2 is 87 μmol g-1 h-1 . This advance represents a first step towards the use of solar energy in urea production. It provides insights into green fertilizer production, and inspires the vision of sustainable, modular plants for distributed production of urea on farms., (© 2021 Wiley-VCH GmbH.)- Published
- 2022
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11. Shining light on CO 2 : from materials discovery to photocatalyst, photoreactor and process engineering.
- Author
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Dong Y, Duchesne P, Mohan A, Ghuman KK, Kant P, Hurtado L, Ulmer U, Loh JYY, Tountas AA, Wang L, Ali FM, Xia M, Dittmeyer R, and Ozin GA
- Abstract
Heterogeneous catalysis, a process in which the reaction of gaseous or liquid chemical reagents is facilitated at the surface of a solid material, is responsible for the majority of industrial-scale chemical and fuel production reactions. The energy required to drive these reactions has historically been derived from the combustion of non-renewable fossil fuels and carries an unavoidably large carbon footprint. More recently, the development of environmentally responsible and sustainable chemical industries is increasingly motivated by greenhouse gas-induced climate change, thus creating demand for eco-friendly heterogeneous catalytic processes. This includes innovative approaches enabled by renewable forms of energy, such as the electrification of chemical and petrochemical processes, utilization of CO
2 as a feedstock and the incorporation of light into catalytic reactions. Herein we review the conversion of solar energy to chemical energy using CO2 , and describe how the photophysical and photochemical properties of nanostructured metal oxide photocatalysts have been engineered to efficiently incorporate light into heterogeneous gas-solid CO2 hydrogenation reactions. Realizing high photonic and energy efficiencies in these systems has demanded innovation in not only photocatalyst engineering, but also photoreactor and process engineering. Rather than exclusively providing an in-depth discussion of the chemistry and science within each individual study, this Tutorial Review highlights the multidisciplinary character of photocatalysis studies by covering the four essential components of a typical research work in this field (materials engineering, theoretical modelling, reactor engineering and process development) via case studies of the archetypal indium oxide catalyst materials. Through advances in these four components, progress has been made towards the ultimate goal of industrializing the production of CO2 -derived chemicals and fuels.- Published
- 2020
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12. Hybrid Photo- and Thermal Catalyst System for Continuous CO 2 Reduction.
- Author
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Mohan A, Ulmer U, Hurtado L, Loh J, Li YF, Tountas AA, Krevert C, Chan C, Liang Y, Brodersen P, Sain MM, and Ozin GA
- Abstract
Heterogeneous thermal catalytic processes are vital for industrial production of fuels, fertilizers, and other chemicals necessary for sustaining human life. However, these processes are highly energy-intensive, requiring a vast consumption of fossil fuels. An emerging class of heterogeneous catalysts that are thermally driven but also exhibit a photochemically enhanced rate can potentially reduce process energy intensity by partially substituting conventional heat (where fossil fuels are needed) with solar energy. Such catalyst systems have yet to be practically utilized. Here, we demonstrate a compact electrically heated photo- and thermal annular reactor module to reduce CO
2 to CO, via the reverse water gas shift reaction. A first-principles-based design approach was taken in developing a SiO2 on an Al photo- and thermal catalyst system for the model photo- and thermal indium oxide hydroxide (In2 O3- x (OH)y ) catalysts. A 5-fold light enhancement in the CO production rate and over 70 h of stable CO production were achieved. This represents the highest light enhancement effect reported for this model photocatalyst to date. The reactor presented herein allows continuous operation and a significant reduction of 31% in heater power consumption when provided with an additional 2 suns of irradiation, demonstrating the strong photo- and thermal-harvesting performances of the catalyst system developed in this work.- Published
- 2020
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13. Bi-allelic variants in RNF170 are associated with hereditary spastic paraplegia.
- Author
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Wagner M, Osborn DPS, Gehweiler I, Nagel M, Ulmer U, Bakhtiari S, Amouri R, Boostani R, Hentati F, Hockley MM, Hölbling B, Schwarzmayr T, Karimiani EG, Kernstock C, Maroofian R, Müller-Felber W, Ozkan E, Padilla-Lopez S, Reich S, Reichbauer J, Darvish H, Shahmohammadibeni N, Tafakhori A, Vill K, Zuchner S, Kruer MC, Winkelmann J, Jamshidi Y, and Schüle R
- Subjects
- Adolescent, Adult, Animals, Calcium metabolism, Cell Line, Tumor, Child, Child, Preschool, Endoplasmic Reticulum metabolism, Female, Gene Knockdown Techniques, High-Throughput Nucleotide Sequencing, Humans, Inositol 1,4,5-Trisphosphate metabolism, Inositol 1,4,5-Trisphosphate Receptors metabolism, Male, Middle Aged, Primary Cell Culture, Signal Transduction, Skin cytology, Spastic Paraplegia, Hereditary metabolism, Zebrafish, Endoplasmic Reticulum-Associated Degradation genetics, Fibroblasts metabolism, Neurons metabolism, Spastic Paraplegia, Hereditary genetics, Ubiquitin-Protein Ligases genetics
- Abstract
Alterations of Ca
2+ homeostasis have been implicated in a wide range of neurodegenerative diseases. Ca2+ efflux from the endoplasmic reticulum into the cytoplasm is controlled by binding of inositol 1,4,5-trisphosphate to its receptor. Activated inositol 1,4,5-trisphosphate receptors are then rapidly degraded by the endoplasmic reticulum-associated degradation pathway. Mutations in genes encoding the neuronal isoform of the inositol 1,4,5-trisphosphate receptor (ITPR1) and genes involved in inositol 1,4,5-trisphosphate receptor degradation (ERLIN1, ERLIN2) are known to cause hereditary spastic paraplegia (HSP) and cerebellar ataxia. We provide evidence that mutations in the ubiquitin E3 ligase gene RNF170, which targets inositol 1,4,5-trisphosphate receptors for degradation, are the likely cause of autosomal recessive HSP in four unrelated families and functionally evaluate the consequences of mutations in patient fibroblasts, mutant SH-SY5Y cells and by gene knockdown in zebrafish. Our findings highlight inositol 1,4,5-trisphosphate signaling as a candidate key pathway for hereditary spastic paraplegias and cerebellar ataxias and thus prioritize this pathway for therapeutic interventions.- Published
- 2019
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14. Cu Atoms on Nanowire Pd/H y WO 3- x Bronzes Enhance the Solar Reverse Water Gas Shift Reaction.
- Author
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Li YF, Lu W, Chen K, Duchesne P, Jelle A, Xia M, Wood TE, Ulmer U, and Ozin GA
- Abstract
Nanowire hydrogen bronzes of WO
3 nanowires decorated with Pd (Pd/Hy WO3- x ) were previously demonstrated to effectively capture broadband radiation across the ultraviolet to near-infrared wavelength range and catalyze the reverse water gas shift reaction (RWGS). Herein, we report a synthetic strategy to enhance the performance of this class of photocatalysts by conformally coating Cu atoms onto the surface of Pd/Hy WO3- x by anchoring Cu(I)Ot Bu to the Brønsted acidic protons of the bronze. The resulting materials are characterized by a suite of analytical methods, including electron microscopy and X-ray absorption spectroscopy. In addition, in situ diffuse reflectance infrared Fourier transform spectroscopy demonstrated that for the light-driven RWGS reaction, as little as 0.2 at. % Cu facilitates the formation of surface carboxylate species from CO2 , resulting in a 300-500% enhancement in the rate of CO production. This metal anchoring method enables atom precise modification of the surfaces of metal oxide nanomaterials for catalytic applications, circumventing the need for complex and expensive atomic layer deposition processes.- Published
- 2019
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15. Fundamentals and applications of photocatalytic CO 2 methanation.
- Author
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Ulmer U, Dingle T, Duchesne PN, Morris RH, Tavasoli A, Wood T, and Ozin GA
- Abstract
The extraction and combustion of fossil natural gas, consisting primarily of methane, generates vast amounts of greenhouse gases that contribute to climate change. However, as a result of recent research efforts, "solar methane" can now be produced through the photocatalytic conversion of carbon dioxide and water to methane and oxygen. This approach could play an integral role in realizing a sustainable energy economy by closing the carbon cycle and enabling the efficient storage and transportation of intermittent solar energy within the chemical bonds of methane molecules. In this article, we explore the latest research and development activities involving the light-assisted conversion of carbon dioxide to methane.
- Published
- 2019
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16. Generation of two iPSC lines derived from two unrelated patients with Gaucher disease.
- Author
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Nagel M, Reichbauer J, Böhringer J, Schelling Y, Krägeloh-Mann I, Schüle R, and Ulmer U
- Subjects
- Alleles, Child, Preschool, Female, Gaucher Disease genetics, Gaucher Disease pathology, Glucosylceramidase metabolism, Homozygote, Humans, Induced Pluripotent Stem Cells pathology, Infant, Kruppel-Like Factor 4, Mutation, Cell Line, Gaucher Disease metabolism, Induced Pluripotent Stem Cells metabolism
- Abstract
Gaucher disease is the most common autosomal recessive lysosomal storage disorder, caused by mutations in the β-glucocerebrosidase gene GBA. Here we describe generation of iPSC from skin-derived fibroblasts from two unrelated individuals with neuronopathic forms of Gaucher disease. The donor for line iPSC-GBA-1, a 21 month old girl, carried the recurring GBA mutation c.1448 T > C, p.Leu483Pro at homozygous state; fibroblasts for line iPS-GBA-2 were obtained from a 4 year old girl compound heterozygous for the GBA mutations c.667 T > C, p.Trp223Arg and c.1226A > G, p.Asn409Ser. iPSCs were developed using integration free episomal vectors (OCT4, KLF4; L-MYC, SOX2 (OSKM) and LIN28). Resource table., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2019
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17. Towards Solar Methanol: Past, Present, and Future.
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Tountas AA, Peng X, Tavasoli AV, Duchesne PN, Dingle TL, Dong Y, Hurtado L, Mohan A, Sun W, Ulmer U, Wang L, Wood TE, Maravelias CT, Sain MM, and Ozin GA
- Abstract
This work aims to provide an overview of producing value-added products affordably and sustainably from greenhouse gases (GHGs). Methanol (MeOH) is one such product, and is one of the most widely used chemicals, employed as a feedstock for ≈30% of industrial chemicals. The starting materials are analogous to those feeding natural processes: water, CO
2 , and light. Innovative technologies from this effort have global significance, as they allow GHG recycling, while providing society with a renewable carbon feedstock. Light, in the form of solar energy, assists the production process in some capacity. Various solar strategies of continually increasing technology readiness levels are compared to the commercial MeOH process, which uses a syngas feed derived from natural gas. These strategies include several key technologies, including solar-thermochemical, photochemical, and photovoltaic-electrochemical. Other solar-assisted technologies that are not yet commercial-ready are also discussed. The commercial-ready technologies are compared using a technoeconomic analysis, and the scalability of solar reactors is also discussed in the context of light-incorporating catalyst architectures and designs. Finally, how MeOH compares against other prospective products is briefly discussed, as well as the viability of the most promising solar MeOH strategy in an international context., Competing Interests: The authors declare no conflict of interest.- Published
- 2019
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18. Pd@H y WO 3- x Nanowires Efficiently Catalyze the CO 2 Heterogeneous Reduction Reaction with a Pronounced Light Effect.
- Author
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Li YF, Soheilnia N, Greiner M, Ulmer U, Wood T, Jelle AA, Dong Y, Yin Wong AP, Jia J, and Ozin GA
- Abstract
The design of photocatalysts able to reduce CO
2 to value-added chemicals and fuels could enable a closed carbon circular economy. A common theme running through the design of photocatalysts for CO2 reduction is the utilization of semiconductor materials with high-energy conduction bands able to generate highly reducing electrons. Far less explored in this respect are low-energy conduction band materials such as WO3 . Specifically, we focus attention on the use of Pd nanocrystal decorated WO3 nanowires as a heretofore-unexplored photocatalyst for the hydrogenation of CO2 . Powder X-ray diffraction, thermogravimetric analysis, ultraviolet-visible-near infrared, and in situ X-ray photoelectron spectroscopy analytical techniques elucidate the hydrogen tungsten bronze, Hy WO3- x , as the catalytically active species formed via the H2 spillover effect by Pd. The existence in Hy WO3- x of Brønsted acid hydroxyls OH, W(V) sites, and oxygen vacancies (VO ) facilitate CO2 capture and reduction reactions. Under solar irradiation, CO2 reduction attains CO production rates as high as 3.0 mmol gcat -1 hr-1 with a selectivity exceeding 99%. A combination of reaction kinetic studies and in situ diffuse reflectance infrared Fourier transform spectroscopy measurements provide a valuable insight into thermochemical compared to photochemical surface reaction pathways, considered responsible for the hydrogenation of CO2 by Pd@Hy WO3- x .- Published
- 2019
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19. Performance Improvement of V-Fe-Cr-Ti Solid State Hydrogen Storage Materials in Impure Hydrogen Gas.
- Author
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Ulmer U, Oertel D, Diemant T, Bonatto Minella C, Bergfeldt T, Dittmeyer R, Behm RJ, and Fichtner M
- Abstract
Two approaches of engineering surface structures of V-Ti-based solid solution hydrogen storage alloys are presented, which enable improved tolerance toward gaseous oxygen (O
2 ) impurities in hydrogen (H2 ) gas. Surface modification is achieved through engineering lanthanum (La)- or nickel (Ni)-rich surface layers with enhanced cyclic stability in an H2 /O2 mixture. The formation of a Ni-rich surface layer does not improve the cycling stability in H2 /O2 mixtures. Mischmetal (Mm, a mixture of La and Ce) agglomerates are observed within the bulk and surface of the alloy when small amounts of this material are added during arc melting synthesis. These agglomerates provide hydrogen-transparent diffusion pathways into the bulk of the V-Ti-Cr-Fe hydrogen storage alloy when the remaining oxidized surface is already nontransparent for hydrogen. Thus, the cycling stability of the alloy is improved in an O2 -containing hydrogen environment as compared to the same alloy without addition of Mm. The obtained surface-engineered storage material still absorbs hydrogen after 20 cycles in a hydrogen-oxygen mixture, while the original material is already deactivated after 4 cycles.- Published
- 2018
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20. Thermochemical Energy Storage through De/Hydrogenation of Organic Liquids: Reactions of Organic Liquids on Metal Hydrides.
- Author
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Ulmer U, Cholewa M, Diemant T, Bonatto Minella C, Dittmeyer R, Behm RJ, and Fichtner M
- Abstract
A study of the reactions of liquid acetone and toluene on transition metal hydrides, which can be used in thermal energy or hydrogen storage applications, is presented. Hydrogen is confined in TiFe, Ti0.95Zr0.05Mn1.49V0.45Fe0.06 ("Hydralloy C5"), and V40Fe8Ti26Cr26 after contact with acetone. Toluene passivates V40Fe8Ti26Cr26 completely for hydrogen desorption while TiFe is only mildly deactivated and desorption is not blocked at all in the case of Hydralloy C5. LaNi5 is inert toward both organic liquids. Gas chromatography (GC) investigations reveal that CO, propane, and propene are formed during hydrogen desorption from V40Fe8Ti26Cr26 in liquid acetone, and methylcyclohexane is formed in the case of liquid toluene. These reactions do not occur if dehydrogenated samples are used, which indicates an enhanced surface reactivity during hydrogen desorption. Significant amounts of carbon-containing species are detected at the surface and subsurface of acetone- and toluene-treated V40Fe8Ti26Cr26 by X-ray photoelectron spectroscopy (XPS). The modification of the surface and subsurface chemistry and the resulting blocking of catalytic sites is believed to be responsible for the containment of hydrogen in the bulk. The surface passivation reactions occur only during hydrogen desorption of the samples.
- Published
- 2016
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21. Metastatic angiosarcoma arising from the right atrium: unusual presentation and excellent response to treatment in a young patient.
- Author
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Fehr M, Kuhn M, Mayer K, Padberg B, Ulmer U, and Cathomas R
- Subjects
- Adult, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Heart Atria drug effects, Hemangiosarcoma drug therapy, Humans, Lung Neoplasms drug therapy, Male, Prognosis, Tomography, X-Ray Computed, Heart Atria pathology, Hemangiosarcoma pathology, Lung Neoplasms secondary
- Published
- 2010
- Full Text
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