@misc{BuchananLewisParisetal., author = {Buchanan, Erin M. and Lewis, Savannah C. and Paris, Bastien and Forscher, Patrick S. and Pavlacic, Jeffrey M. and Beshears, Julie E. and Drexler, Shira Meir and Gourdon-Kanhukamwe, Am{\´e}lie and Mallik, Peter R and Silan, Miguel Alejandro A. and Miller, Jeremy K. and IJzerman, Hans and Moshontz, Hannah and Beaudry, Jennifer L. and Suchow, Jordan W. and Chartier, Christopher R. and Coles, Nicholas A. and Sharifian, MohammadHasan and Todsen, Anna Louise and Levitan, Carmel A. and Azevedo, Fl{\´a}vio and Legate, Nicole and Heller, Blake and Rothman, Alexander J. and Dorison, Charles A. and Gill, Brian P. and Wang, Ke and Rees, Vaughan W. and Gibbs, Nancy and Goldenberg, Amit and Thi Nguyen, Thuy-vy and Gross, James J. and Kaminski, Gwena{\^e}l and von Bastian, Claudia C. and Paruzel-Czachura, Mariola and Mosannenzadeh, Farnaz and Azouaghe, Soufian and Bran, Alexandre and Ruiz-Fernandez, Susana and Santos, Anabela Caetano and Reggev, Niv and Zickfeld, Janis H. and Akkas, Handan and Pantazi, Myrto and Ropovik, Ivan and Korbmacher, Max and Arriaga, Patr{\´i}cia and Gjoneska, Biljana and Warmelink, Lara and Alves, Sara G. and de Holanda Coelho, Gabriel Lins and Stieger, Stefan and Schei, Vidar and Hanel, Paul H. P. and Szaszi, Barnabas and Fedotov, Maksim and Antfolk, Jan and Marcu, Gabriela-Mariana and Schr{\"o}tter, Jana and Kunst, Jonas R. and Geiger, Sandra J. and Adetula, Adeyemi and Kocalar, Halil Emre and Kielińska, Julita and Kačm{\´a}r, Pavol and Bokkour, Ahmed and Galindo-Caballero, Oscar J. and Djamai, Ikhlas and P{\"o}ntinen, Sara Johanna and AGESIN, Bamikole Emmanuel and Jerns{\"a}ther, Teodor and Urooj, Anum and Rachev, Nikolay R. and Koptjevskaja-Tamm, Maria and Kurfal{\i}, Murathan and Pit, Ilse L. and Li, Ranran and {\c{C}}oksan, Sami and Dubrov, Dmitrii and Paltrow, Tamar Elise and Ban{\´i}k, Gabriel and Korobova, Tatiana and Studzinska, Anna and Jiang, Xiaoming and Aruta, John Jamir Benzon R. and Vintr, J{\´a}chym and Chiu, Faith and Kaliska, Lada and Berkessel, Jana B. and T{\"u}mer, Murat and Morales-Izquierdo, Sara and Chuan-Peng, Hu and Vezirian, Kevin and Rosa, Anna Dalla and Bialobrzeska, Olga and Vasilev, Martin R. and Beitner, Julia and K{\´a}cha, Ondřej and Žuro, Barbara and Westerlund, Minja and Nedelcheva-Datsova, Mina and Findor, Andrej and Krupić, Dajana and Kowal, Marta and Askelund, Adrian Dahl and Pourafshari, Razieh and Đorđević, Jasna Milošević and Schmidt, Nadya-Daniela and Baklanova, Ekaterina and Szala, Anna and Zakharov, Ilya and Vranka, Marek A. and Ihaya, Keiko and Grano, Caterina and Cellini, Nicola and Białek, Michał and Anton-Boicuk, Lisa and Dalgar, Ilker and Ad{\i}g{\"u}zel, Arca and Verharen, Jeroen P. H. and Maturan, Princess Lovella G. and Kassianos, Angelos P. and Oliveira, Raquel and Čadek, Martin and Adoric, Vera Cubela and {\"O}zdoğru, Asil Ali and Sverdrup, Therese E. and Aczel, Balazs and Zambrano, Danilo and Ahmed, Afroja and Tamnes, Christian K. and Yamada, Yuki and Volz, Leonhard and Sunami, Naoyuki and Suter, Lilian and Vieira, Luc and Groyecka-Bernard, Agata and Kamburidis, Julia Arhondis and Reips, Ulf-Dietrich and Harutyunyan, Mikayel and Adetula, Gabriel Agboola and Allred, Tara Bulut and Barzykowski, Krystian and Antazo, Benedict G and Zsido, Andras N. and Šakan, Dušana Dušan and Cyrus-Lai, Wilson and Ahlgren, Lina Pernilla and Hruška, Matej and Vega, Diego and Manunta, Efisio and Mokady, Aviv and Capizzi, Mariagrazia and Martončik, Marcel and Say, Nicolas and Filip, Katarzyna and Vilar, Roosevelt and Staniaszek, Karolina and Vdovic, Milica and Adamkovic, Matus and Johannes, Niklas and Hajdu, Nandor and Cohen, Noga and Overkott, Clara and Krupić, Dino and Hubena, Barbora and Nilsonne, Gustav and Mioni, Giovanna and Solorzano, Claudio Singh and Ishii, Tatsunori and Chen, Zhang and Kushnir, Elizaveta and Karaarslan, Cemre and Ribeiro, Rafael R. and Khaoudi, Ahmed and Kossowska, Małgorzata and Bavolar, Jozef and Hoyer, Karlijn and Roczniewska, Marta and Karababa, Alper and Becker, Maja and Monteiro, Renan P. and Kunisato, Yoshihiko and Metin-Orta, Irem and Adamus, Sylwia and Kozma, Luca and Czarnek, Gabriela and Domurat, Artur and Štrukelj, Eva and Alvarez, Daniela Serrato and Parzuchowski, Michal and Massoni, S{\´e}bastien and Czamanski-Cohen, Johanna and Pronizius, Ekaterina and Muchembled, Fany and van Schie, Kevin and Sa{\c{c}}akl{\i}, Asl{\i} and Hristova, Evgeniya and Kuzminska, Anna O. and Charyate, Abdelilah and Bijlstra, Gijsbert and Afhami, Reza and Majeed, Nadyanna M. and Musser, Erica D. and Sirota, Miroslav and Ross, Robert M. and Yeung, Siu Kit and Papadatou-Pastou, Marietta and Foroni, Francesco and Almeida, In{\^e}s A. T. and Grigoryev, Dmitry and Lewis, David M. G. and Holford, Dawn L. and Janssen, Steve M. J. and Tatachari, Srinivasan and Batres, Carlota and Olofsson, Jonas K. and Daches, Shimrit and Belaus, Anabel and Pfuhl, Gerit and Corral-Frias, Nadia Sarai and Sousa, Daniela and R{\"o}er, Jan Philipp and Isager, Peder Mortvedt and Godbersen, Hendrik and Walczak, Radoslaw B. and Van Doren, Natalia and Ren, Dongning and Gill, Tripat and Voracek, Martin and DeBruine, Lisa M. and Anne, Michele and Očovaj, Sanja Batić and Thomas, Andrew G. and Arvanitis, Alexios and Ostermann, Thomas and Wolfe, Kelly and Arinze, Nwadiogo Chisom and Bundt, Carsten and Lamm, Claus and Calin-Jageman, Robert J and Davis, William E. and Karekla, Maria and Zorjan, Saša and Jaremka, Lisa M. and Uttley, Jim and Hricova, Monika and Koehn, Monica A and Kiselnikova, Natalia and Bai, Hui and Krafnick, Anthony J. and Balci, Busra Bahar and Ballantyne, Tonia and Lins, Samuel and Vally, Zahir and Esteban-Serna, Celia and Schmidt, Kathleen and Macapagal, Paulo Manuel L. and Szwed, Paulina and Zdybek, Przemysław Marcin and Moreau, David and Collins, W. Matthew and Joy-Gaba, Jennifer A. and Vilares, Iris and Tran, Ulrich S. and Boudesseul, Jordane and Albayrak-Aydemir, Nihan and Dixson, Barnaby James Wyld and Perillo, Jennifer T and Ferreira, Ana and Westgate, Erin C. and Aberson, Christopher L. and Arinze, Azuka Ikechukwu and Jaeger, Bastian and Butt, Muhammad Mussaffa and Silva, Jaime R. and Storage, Daniel Shafik and Janak, Allison P and Jim{\´e}nez-Leal, William and Soto, Jose A. and Sorokowska, Agnieszka and McCarthy, Randy and Tullett, Alexa M and Frias-Armenta, Martha and Ribeiro, Matheus Fernando Felix and Hartanto, Andree and Forbes, Paul A. G. and Willis, Megan L. and del Carmen Tejada R, Mar{\´i}a and Torres, Adriana Julieth Olaya and Stephen, Ian D and Vaidis, David C. and de la Rosa-G{\´o}mez, Anabel and Yu, Karen and Sutherland, Clare A. M. and Manavalan, Mathi and Behzadnia, Behzad and Urban, Jan and Baskin, Ernest and McFall, Joseph P. and Ogbonnaya, Chisom Esther and Fu, Cynthia H. Y. and Rahal, Rima-Maria and Ndukaihe, Izuchukwu L. G. and Hostler, Thomas J. and Kappes, Heather Barry and Sorokowski, Piotr and Khosla, Meetu and Lazarevic, Ljiljana B. and Eudave, Luis and Vilsmeier, Johannes K. and Luis, Elkin O. and Muda, Rafał and Agadullina, Elena and C{\´a}rcamo, Rodrigo A. and Reeck, Crystal and Anjum, Gulnaz and Venegas, M{\´o}nica Camila Toro and Misiak, Michal and Ryan, Richard M. and Nock, Nora L. and Travaglino, Giovanni A. and Mensink, Michael C. and Feldman, Gilad and Wichman, Aaron L. and Chou, Weilun and Ziano, Ignazio and Seehuus, Martin and Chopik, William J. and Kung, Franki Y. H. and Carpentier, Joelle and Vaughn, Leigh Ann and Du, Hongfei and Xiao, Qinyu and Lima, Tiago J. S. and Noone, Chris and Onie, Sandersan and Verbruggen, Frederick and Radtke, Theda and Primbs, Maximilian A.}, title = {The psychological science accelerator's COVID-19 rapid-response dataset}, series = {Scientific Data}, volume = {10}, journal = {Scientific Data}, number = {1}, publisher = {Springer Science and Business Media LLC}, issn = {2052-4463}, doi = {10.1038/s41597-022-01811-7}, pages = {1 -- 15}, language = {en} } @misc{HallSchmidtWaggeetal., author = {Hall, Braeden and Schmidt, Kathleen and Wagge, Jordan and Lewis, Savannah C. and Weissgerber, Sophia C. and Kiunke, Felix and Pfuhl, Gerit and Stieger, Stefan and Tran, Ulrich S. and Barzykowski, Krystian and Bogatyreva, Natalia and Kowal, Marta and Massar, KarlIJn and Pernerstofer, Felizitas and Sorokowski, Piotr and Voracek, Martin and Chartier, Christopher R. and Brandt, Mark J. and Grahe, Jon E. and {\"O}zdoğru, Asil A. and Andreychik, Michael R. and Chen, Sau-Chin and Evans, Thomas R. and Hautekiet, Caro and IJzerman, Hans and Kačm{\´a}r, Pavol and Krafnick, Anthony J. and Musser, Erica D. and Vergauwe, Evie and Werner, Kaitlyn M. and Aczel, Balazs and Arriaga, Patr{\´i}cia and Batres, Carlota and Beaudry, Jennifer L. and Cova, Florian and Ďurbisov{\´a}, Simona and Cramblet Alvarez, Leslie D. and Feldman, Gilad and Godbersen, Hendrik and Gottfried, Jaroslav and Haeffel, Gerald J. and Hartanto, Andree and Isloi, Chris and McFall, Joseph P. and Milyavskaya, Marina and Moreau, David and Nos{\´a}ľov{\´a}, Ester and Papaioannou, Kostas and Ruiz-Fernandez, Susana and Schr{\"o}tter, Jana and Storage, Daniel and Vezirian, Kevin and Volz, Leonhard and Weisberg, Yanna J. and Xiao, Qinyu and Awlia, Dana and Branit, Hannah W. and Dunn, Megan R. and Groyecka-Bernard, Agata and Haneda, Ricky and Kielinska, Julita and Kolle, Caroline and Lubomski, Paweł and Miller, Alexys M. and M{\ae}kel{\ae}, Martin J. and Pantazi, Mytro and Ribeiro, Rafael R. and Ross, Robert M. and Sorokowska, Agnieszka and Aberson, Christopher L. and Vassiliou, Xanthippi Alexi and Baker, Bradley J. and Bognar, Miklos and Cong, Chin Wen and Danvers, Alex F. and Davis, William E. and Dranseika, Vilius and Dumbravă, Andrei and Farmer, Harry and Field, Andy P. and Forscher, Patrick S. and Graton, Aur{\´e}lien and Hajdu, Nandor and Howlett, Peter A. and Kabut, Radosław and Larsen, Emmett M. and Lee, Sean T. H. and Legate, Nicole and Levitan, Carmel A. and Levy, Neil and Lu, Jackson G. and Misiak, Michał and Morariu, Roxana E. and Novak, Jennifer and Pronizius, Ekaterina and Prusova, Irina and Rathnayake, Athulya S. and Romanova, Marina O. and R{\"o}er, Jan P. and Sampaio, Waldir M. and Schild, Christoph and Schulte-Mecklenbeck, Michael and Stephen, Ian D. and Szecsi, Peter and Takacs, Elizabeth and Teeter, Julia N. and Thiele-Evans, Elian H. and Valeiro-Paterlini, Julia and Vilares, Iris and Villafana, Louise and Wang, Ke and Wu, Raymond and {\´A}lvarez-Solas, Sara and Moshontz, Hannah and Buchanan, Erin M.}, title = {Registered Replication Report: A Large Multilab Cross-Cultural Conceptual Replication of Turri et al. (2015)}, series = {Advances in Methods and Practices in Psychological Science}, volume = {7}, journal = {Advances in Methods and Practices in Psychological Science}, number = {4}, publisher = {SAGE Publications}, issn = {2515-2459}, doi = {10.1177/25152459241267902}, pages = {1 -- 38}, language = {en} } @inproceedings{KersteinGlaweSchmidtetal., author = {Kerstein, Alan R. and Glawe, Christoph and Schmidt, Heiko and Klein, Rupert and Gonzalez-Juez, Esteban D. and Schmidt, Rodney}, title = {Computational modeling of scalar transport and buoyancy effects in turbulent flows using ODTLES}, series = {Bulletin of the American Physical Society}, volume = {57}, booktitle = {Bulletin of the American Physical Society}, number = {17}, language = {en} } @inproceedings{RistauMeierEgbersetal., author = {Ristau, R. and Meier, M. and Egbers, Christoph and Schmidt, J.-R. and Poppe, T.}, title = {Partikelbeladene Str{\"o}mungen : Simulation und Messtechnik}, language = {de} } @inproceedings{BergCordsenHeueretal., author = {Berg, R. and Cordsen, J. and Heuer, J. and Nolte, J{\"o}rg and Oestmann, B. and Sander, M. and Schmidt, Heiko and Sch{\"o}n, F. and Schr{\"o}der-Preikschat, Wolfgang}, title = {The PEACE Family of Distributed Operating Systems}, language = {en} } @inproceedings{BergCordsenHastedtetal., author = {Berg, R. and Cordsen, J. and Hastedt, Ch. and Heuer, J. and Nolte, J{\"o}rg and Sander, M. and Schmidt, Heiko and Sch{\"o}n, F. and Schr{\"o}der-Preikschat, Wolfgang}, title = {Making Massively Parallel Systems Work}, language = {en} } @misc{DudekLupinaKozłowskietal., author = {Dudek, Piotr T. and Lupina, Grzegorz and Kozłowski, Grzegorz and Zaumseil, Peter and Bauer, Jakob and Fursenko, Oksana and Dabrowski, Jarek Marek and Schmidt, R. and Lippert, Gunther and M{\"u}ssig, Hans-Joachim and Schr{\"o}der, Thomas and Schmeißer, Dieter and Zschech, Ehrenfried}, title = {Atomic-scale engineering of future high-k dynamic random access memory dielectrics: The example of partial Hf substitution by Ti in BaHfO3}, series = {Journal of Vacuum Science and Technology / B}, volume = {29}, journal = {Journal of Vacuum Science and Technology / B}, number = {1}, issn = {2166-2754}, language = {en} } @misc{SchmidtKersteinNedelecetal., author = {Schmidt, Heiko and Kerstein, Alan R. and N{\´e}d{\´e}lec, Renaud and Wunsch, Scott and Sayler, Ben J.}, title = {Numerical study of radiatively induced entrainment}, series = {Journal of Physics: Conference Series}, volume = {318}, journal = {Journal of Physics: Conference Series}, issn = {1742-6588}, doi = {10.1088/1742-6596/318/7/072017}, pages = {072017}, language = {en} } @misc{SchmidtKersteinNedelecetal., author = {Schmidt, Heiko and Kerstein, Alan R. and N{\´e}d{\´e}lec, Renaud and Wunsch, Scott and Sayler, Ben J.}, title = {Analysis and numerical simulation of a laboratory analog of radiatively induced cloud-top entrainment}, series = {Theoretical Computational Fluid Dynamics}, journal = {Theoretical Computational Fluid Dynamics}, issn = {1432-2250}, doi = {10.1007/s00162-012-0288-4}, pages = {19}, language = {en} } @misc{OevermannSchmidtKerstein, author = {Oevermann, Michael and Schmidt, Heiko and Kerstein, Alan R.}, title = {HCCI combustion modeling using detailed chemistry coupled to LEM-based advection}, series = {Combustion and Flame}, volume = {155}, journal = {Combustion and Flame}, number = {3}, issn = {1556-2921}, pages = {370 -- 379}, language = {en} } @misc{SchulzGlaweSchmidtetal., author = {Schulz, Falko T. and Glawe, Christoph and Schmidt, Heiko and Kerstein, Alan R.}, title = {Toward modeling of CO2 multi-phase flow patterns using a stochastic multi-scale approach}, series = {Environmental Earth Sciences}, volume = {70}, journal = {Environmental Earth Sciences}, number = {8}, issn = {1866-6299}, doi = {10.1007/s12665-013-2461-5}, pages = {3739 -- 3748}, language = {en} } @inproceedings{SchulzGlaweSchmidtetal., author = {Schulz, Falko T. and Glawe, Christoph and Schmidt, Heiko and Kerstein, Alan R.}, title = {Liquid jet simulation using one-dimensional turbulence}, series = {14th European Turbulence Conference, Lyon, France, September 1-4, 2013}, booktitle = {14th European Turbulence Conference, Lyon, France, September 1-4, 2013}, language = {en} } @inproceedings{SchulzGlaweKersteinetal., author = {Schulz, Falko T. and Glawe, Christoph and Kerstein, Alan R. and Schmidt, Heiko}, title = {Toward modeling of supercritical CO2 flow using map-based advection}, series = {EGU General Assembly 2012, held 22-27 April, 2012 in Vienna}, booktitle = {EGU General Assembly 2012, held 22-27 April, 2012 in Vienna}, language = {en} } @inproceedings{SchmidtKerstein, author = {Schmidt, Heiko and Kerstein, Alan R.}, title = {Modeling of wind-field fluctuations using the one-dimensional-turbulence model}, series = {The Science of Making Torque from Wind, Oldenburg, Germany, October 9-11, 2012 Oldenburg Germany}, booktitle = {The Science of Making Torque from Wind, Oldenburg, Germany, October 9-11, 2012 Oldenburg Germany}, language = {en} } @inproceedings{SchmidtKerstein, author = {Schmidt, Heiko and Kerstein, Alan R.}, title = {Towards a multiscale strategy for modeling high-pressure flow of carbon dioxide for sequestration}, series = {Geoenergy 2010, Potsdam, Germany}, booktitle = {Geoenergy 2010, Potsdam, Germany}, pages = {2}, language = {en} } @inproceedings{NedelecSchmidtWunschetal., author = {N{\´e}d{\´e}lec, Renaud and Schmidt, Heiko and Wunsch, Scott and Sayler, Ben J. and Kerstein, Alan R.}, title = {Comparison of Entrainment Rates from a Tank Experiment with Results Us- ing the One-Dimensional-Turbulence Model}, series = {EGU General Assembly 2010, held in Vienna, Austria, 02 - 07 May 2010}, booktitle = {EGU General Assembly 2010, held in Vienna, Austria, 02 - 07 May 2010}, language = {en} } @inproceedings{OevermannSchmidtKerstein, author = {Oevermann, Michael and Schmidt, Heiko and Kerstein, Alan R.}, title = {Linear eddy modeling of n-heptane combustion in HCCI engines}, series = {12th SIAM International Conference on Numerical Combustion}, booktitle = {12th SIAM International Conference on Numerical Combustion}, pages = {S. 20}, language = {en} } @misc{SchmidtKersteinNedelecetal., author = {Schmidt, Heiko and Kerstein, Alan R. and N{\´e}d{\´e}lec, Renaud and Wunsch, Scott and Sayler, Ben J.}, title = {One-dimensional turbulence simulation of a laboratory analog of radiatively induced cloud-top entrainment}, language = {en} } @inproceedings{SchmidtSchulzKerstein, author = {Schmidt, Heiko and Schulz, Falko T. and Kerstein, Alan R.}, title = {Toward modeling of multi- phase flow patterns using a combination of level sets and one-dimensional turbulence}, series = {EGU General Assembly 2011, Vienna, Austria, 03 - 08 April 2011}, booktitle = {EGU General Assembly 2011, Vienna, Austria, 03 - 08 April 2011}, language = {en} } @misc{KersteinSchmidtNedelecetal., author = {Kerstein, Alan R. and Schmidt, Heiko and N{\´e}d{\´e}lec, Renaud and Wunsch, Scott and Sayler, Ben J.}, title = {Analysis and numerical simulation of a laboratory analog of radiatively induced cloud-top entrainment}, series = {Bulletin of the American Physical Society Dynamics}, volume = {55}, journal = {Bulletin of the American Physical Society Dynamics}, number = {16}, language = {en} } @inproceedings{GlaweKleinKersteinetal., author = {Glawe, Christoph and Klein, Rupert and Kerstein, Alan R. and Schmidt, Heiko}, title = {Towards the simulation of gravity waves using the One-Dimensional Turbulence model}, series = {EGU General Assembly 2012, held 22-27 April, 2012 in Vienna}, booktitle = {EGU General Assembly 2012, held 22-27 April, 2012 in Vienna}, language = {en} } @misc{SoniaRichterBrunneretal., author = {Sonia, G. and Richter, E. and Brunner, F. and Denker, A. and Lossy, R. and Mai, M. and Lenk, Friedrich and Bundesmann, J. and Pensl, G. and Schmidt, J. and Zeimer, U. and Wang, L. and Baskar, K. and Weyers, M. and W{\"u}rfl, Joachim and Tr{\"a}nkle, G{\"u}nther}, title = {2 MeV ion irradiation effects on AlGaN/GaN HFET devices}, series = {Solid-State Electronics}, volume = {52}, journal = {Solid-State Electronics}, number = {7}, issn = {0038-1101}, pages = {1011 -- 1017}, abstract = {AlGaN/GaN heterostructure field effect transistors (HFETs) were irradiated with 2 MeV protons, carbon, oxygen, iron and krypton ions with fluences ranging from 1 × 109 cm-2 to 1 × 1013 cm-2. DC, pulsed I-V characteristics, loadpull and S-parameters of the AlGaN HFET devices were measured before and after irradiation. In parallel, a thick GaN reference layer was also irradiated with the same ions and was characterized by X-ray diffraction, photoluminescence, Hall measurements before and after irradiation. Small changes in the device performance were observed after irradiation with carbon and oxygen at a fluence of 5 × 1010 cm-2. Remarkable changes in device characteristics were seen at a fluence of 1 × 1012 cm-2 for carbon, oxygen, iron and krypton irradiation. Similarly, remarkable changes were also observed in the GaN layer for irradiations with fluence of 1 × 1012 cm-2. The results found on devices and on the GaN layer were compared and correlated.}, language = {en} } @misc{GnanapragasamRichterBrunneretal., author = {Gnanapragasam, S. and Richter, E. and Brunner, F. and Denker, A. and Lossy, R. and Mai, M. and Lenk, Friedrich and Opitz-Coutureau, J. and Pensl, G. and Schmidt, J. and Zeimer, U. and Wang, L. and Krishnan, B. and Weyers, M. and W{\"u}rfl, Joachim and Tr{\"a}nkle, G{\"u}nther}, title = {Irradiation effects on AlGaN HFET devices and GaN layers}, series = {Journal of Materials Science: Materials in Electronics}, volume = {19}, journal = {Journal of Materials Science: Materials in Electronics}, number = {1}, issn = {1573-482X}, doi = {10.1007/s10854-008-9589-1}, pages = {64 -- 67}, abstract = {AlGaN/GaN heterostructure field effect transistors (HFETs) were irradiated with protons as well as carbon, oxygen, iron and krypton ions of high (68 and 120 MeV) and low (2 MeV) energy with fluences in the range from 1x107 to 1x1013 cm-2. High energy irradiation with protons, carbon and oxygen produced no degradation in devices while krypton irradiation at the fluence of 1x1010 cm-2 resulted in a small reduction of 2\% in the transconductance. Similarly, for GaN samples irradiated with protons, carbon and oxygen at high energy no changes were seen by XRD, PL and Hall effect, while changes in lattice constant and a reduction in PL intensity were observed after irradiation with high energy krypton. Low energy irradiation with carbon and oxygen at a fluence of 5x1010 cm-2 results in small change in the device performance while remarkable changes in device characteristics are seen at a fluence of 1x1012 cm-2 for carbon, oxygen, iron and krypton irradiation. Similarly changes are also observed by XRD, PL and Hall effect for the thick GaN layer irradiated at the fluence of 1x1012 cm-2. The device results and GaN layer properties are strongly correlated.}, language = {en} } @misc{SoniaRichterBrunneretal., author = {Sonia, G. and Richter, E. and Brunner, F. and Denker, A. and Lossy, R. and Lenk, Friedrich and Opitz-Coutureau, J. and Mai, M. and Schmidt, J. and Zeimer, U. and Wang, L. and Baskar, K. and Weyers, M. and W{\"u}rfl, Joachim and Tr{\"a}nkle, G{\"u}nther}, title = {High energy irradiation effects on AlGaN/GaN HFET devices}, series = {Semiconductor Science and Technology}, volume = {22}, journal = {Semiconductor Science and Technology}, number = {11}, issn = {0268-1242}, doi = {10.1088/0268-1242/22/11/007}, pages = {1220 -- 1224}, abstract = {The effect of proton, carbon, oxygen and krypton irradiation on AlGaN HFET devices has been studied. Irradiation was performed at 68 and 120 MeV with fluences in the range from 1 × 10^7 to 1 × 10^13 cm2 . Before and after irradiation, dc and pulsed I - V characteristics, loadpull and S -parameters of the AlGaN HFET devices were measured. A thick GaN reference layer was characterized by x-ray diffraction, photoluminescence and Hall measurements before and after irradiation. Proton, carbon and oxygen irradiation show no degradation in devices while krypton irradiation shows a small change at a fluence of 1 × 10 10 cm2 in the device characteristics. The device results are correlated with the thick GaN results.}, language = {en} } @inproceedings{MovagharLinneOevermannetal., author = {Movaghar, Amirreza and Linne, Mark and Oevermann, Michael and Meiselbach, Falko T. and Schmidt, Heiko and Kerstein, Alan R.}, title = {Numerical study of liquid breakup at the surface of turbulent liquid jets using One-Dimensional Turbulence}, series = {26th Annual Conference on Liquid Atomization and Spray Systems, ILASS, proceedings of the Conference, Bremen, Germany, 08.09.2014 - 10.09.2014}, booktitle = {26th Annual Conference on Liquid Atomization and Spray Systems, ILASS, proceedings of the Conference, Bremen, Germany, 08.09.2014 - 10.09.2014}, address = {Bremen}, isbn = {978-3-00-047070-7}, abstract = {This paper presents an investigation of primary breakup of planar turbulent liquid jets and breakup properties at the surface of turbulent jets in still air at standard conditions. Numerical simulations are carried out for jet exit Reynolds number 23000 and Weber numbers in the range [102-107]. Due to the limitation of direct numerical simulation (DNS) to moderate Reynolds numbers, a stochastic 1D ansatz based on the one-dimensional turbulence (ODT) model is used to simulate a planar liquid jet with a high lateral resolution. ODT permits an affordable high resolution of interface and single-phase property gradients which are key for understanding the local behavior. ODT is a stochastic model simulating turbulent flow evolution along a notional 1D line of sight by applying instantaneous maps to represent the effect of individual turbulent eddies on property profiles. The most relevant mechanisms that influence the primary breakup of liquid jets are found to be represented accurately based on comparisons to experiments and correlations reported in the literature. Building on this finding, future work will focus on the statistics of droplets generated by primary breakup, both to investigate their relationship to breakup mechanisms and to provide input to models of secondary breakup and subsequent spray evolution.}, language = {en} } @inproceedings{GlaweSchmidtKerstein, author = {Glawe, Christoph and Schmidt, Heiko and Kerstein, Alan R.}, title = {ODTLES: Mulitscale turbulence modeling and buoyant application}, series = {Book of abstracts, 7th European Postgraduate Fluid Dynamics Conference, Ilmenau, Germany, 14th - 17th, July 2014}, booktitle = {Book of abstracts, 7th European Postgraduate Fluid Dynamics Conference, Ilmenau, Germany, 14th - 17th, July 2014}, address = {Ilmenau}, pages = {S.46}, language = {en} } @misc{JozefikKersteinSchmidtetal., author = {Jozefik, Zoltan and Kerstein, Alan R. and Schmidt, Heiko and Lyra, Sgouria and Kolla, Hemanth and Chen, Jackie H.}, title = {One-dimensional turbulence modeling of a turbulent counterflow flame with comparison to DNS}, series = {Combustion and Flame}, volume = {162}, journal = {Combustion and Flame}, number = {8}, issn = {1556-2921}, pages = {2999 -- 3015}, language = {en} } @misc{SchmidtGlaweJozefiketal., author = {Schmidt, Heiko and Glawe, Christoph and Jozefik, Zoltan and Meiselbach, Falko T. and Kerstein, Alan R.}, title = {On the benefits of ODT-based stochastic turbulence modeling}, series = {Proceedings in applied mathematics and mechanics : PAMM}, volume = {14}, journal = {Proceedings in applied mathematics and mechanics : PAMM}, number = {1}, issn = {1617-7061}, pages = {655 -- 656}, abstract = {We summarize the group's progress in applying, analyzing, and improving ODT and ODT-based stochastic turbulence models like ODTLES. Compared to DNS these models span a wider range of scales while compared to RANS/LES (i) the molecular effects are retained and (ii) no assumption of scale separation is made. In this regard ODTLES has more properties of DNS than of standard LES.}, language = {en} } @incollection{JozefikKersteinSchmidt, author = {Jozefik, Zoltan and Kerstein, Alan R. and Schmidt, Heiko}, title = {Towards a compressible reactive multiscale approach based on One-Dimensional Turbulence}, series = {Active Flow and Combustion Control 2014}, booktitle = {Active Flow and Combustion Control 2014}, editor = {King, Rudibert}, publisher = {Springer}, address = {Switzerland}, isbn = {978-3-319-11967-0}, pages = {197 -- 211}, abstract = {Due to its huge complexity, progress in understanding and prediction of turbulent combustion is extremely challenging. In principle, progress is possible without improved understanding through direct numerical solution (DNS) of the exact governing equations, but the wide range of spatial and temporal scales often renders it unaffordable, so coarse-grained 3D numerical simulations with subgrid parameterization of the unresolved scales are often used. This is especially problematic for multi-physics regimes such as reacting flows because much of the complexity is thus relegated to the unresolved small scales. One-Dimensional Turbulence (ODT) is an alternative stochastic model for turbulent flow simulation. It operates on a 1D spatial domain via time advancing individual flow realizations rather than ensemble-averaged quantities. The lack of spatial and temporal filtering on this 1D domain enables a physically sound multiscale treatment which is especially useful for combustion applications where, e.g., sharp interfaces or small chemical time scales have to be resolved. Lignell et al. recently introduced an efficient ODT implementation using an adaptive mesh. As all existing ODT versions it operates in the incompressible regime and thus cannot handle compressibility effects and their interactions with turbulence and chemistry which complicate the physical picture even further. In this paper we make a first step toward an extension of the ODT methodology towards an efficient compressible implementation. The necessary algorithmic changes are highlighted and preliminary results for a standard non-reactive shock tube problem as well as for a turbulent reactive case illustrate the potential of the extended approach.}, language = {en} } @inproceedings{StollbergSchmidtNamangoetal., author = {Stollberg, Christian and Schmidt, M. and Namango, Saul and Pohl, R. and Ay, Peter}, title = {Conditioning, Identification and Automatic Sorting of Plastic Automotive Parts for Productive Recycling}, series = {International Automobile Recycling Congress, IARC 2002, Geneva, Switzerland, March 13 - 15, 2002, proceedings}, booktitle = {International Automobile Recycling Congress, IARC 2002, Geneva, Switzerland, March 13 - 15, 2002, proceedings}, publisher = {ICM AG}, address = {Muri}, language = {en} } @inproceedings{StollbergNamangoSchmidtetal., author = {Stollberg, Christian and Namango, Saul and Schmidt, M. and Pohl, R. and Ay, Peter}, title = {Preparation of plastics for automatic identification as the first step in recycling of automotive parts}, series = {Proceedings of the XXII International Mineral Processing Congress, Cape Town, South Africa, 29 September - 3 October 2003}, booktitle = {Proceedings of the XXII International Mineral Processing Congress, Cape Town, South Africa, 29 September - 3 October 2003}, publisher = {South African Institute of Mining \& Meta}, address = {Marshalltown, South Africa}, language = {en} } @misc{JahnBlaudeckBaumannetal., author = {Jahn, Stephan F. and Blaudeck, Thomas and Baumann, Reinhard R. and Jakob, Alexander and Ecorchard, Petra and R{\"u}ffer, Tobias and Lang, Heinrich and Schmidt, Peer}, title = {Inkjet Printing of Conductive Silver Patterns by Using the First Aqueous Particle-Free MOD Ink without Additional Stabilizing Ligands}, series = {Chemistry of Materials}, volume = {22}, journal = {Chemistry of Materials}, number = {10}, issn = {1520-5002}, doi = {10.1021/cm9036428}, pages = {3067 -- 3071}, abstract = {The chemical and physical properties of [AgO2C(CH2OCH2)3H] (3) and its use as an aqueous, ligand-free MOD ink (MOD = metal-organic decomposition) for piezo inkjet printing is discussed. The printed, thermal, or photochemical sintered silver features are electrically conductive on glass (2.7 × 107 S m-1) and PET (PET = polyethylene terephthalate) substrates (1.1 × 107 S m-1) corresponding to 43\% and 18\% of the bulk silver conductivity. Conducted tape tests show the suitability of the ink for particularly polymer substrates. TG-MS studies demonstrate a two-step decomposition for the conversion of 3 to elemental silver. The structure of 3 in the solid state was determined by single X-ray structure determination.}, language = {en} } @misc{JahnJakobBlaudecketal., author = {Jahn, Stephan F. and Jakob, Alexander and Blaudeck, Thomas and Schmidt, Peer and Lang, Heinrich and Baumann, Reinhard R.}, title = {Inkjet printing of conductive patterns with an aqueous solution of [AgO2C(CH2OCH2)3H] without any additional stabilizing ligands}, series = {Thin Solid Films}, volume = {518}, journal = {Thin Solid Films}, number = {12}, issn = {0040-6090}, doi = {10.1016/j.tsf.2010.01.030}, pages = {3218 -- 3222}, abstract = {The use of silver(I)-2-[2-(2-methoxyethoxy)ethoxy]acetate, [AgO2C(CH2OCH2)3H], and its application as an aqueous metal-organic decomposition (MOD) inkjet ink is reported. The chemical and physical properties of the silver carboxylate and the ink formulated thereof are discussed. The ink meets all requirements of piezo driven inkjet printing. The printed features were converted into electrically conducting silver patterns by thermal or photo-thermal treatment. The conversion of [AgO2C(CH2OCH2)3H] to elemental silver follows a two-step decomposition as demonstrated by thermogravimetry-mass spectrometry (TG-MS) measurements. The measured conductivities of the printed features on glass and polyethylene-terephthalate (PET) are 2.7 × 107 S m-1 and 1.1 × 107 S m-1, respectively, which correspond to 43\% (glass) and 18\% (PET) of the bulk silver conductivity.}, language = {en} } @inproceedings{BlehOstendorfMertenetal., author = {Bleh, D. and Ostendorf, Ralf and Merten, A. and Grahmann, Jan and Schenk, Harald and Kunzer, M. and Schmidt, R. and Wagner, J.}, title = {Miniaturization of a fast tunable external cavity QCL with customized gratings and MOEMS components}, series = {International Quantum Cascade Lasers School \& Workshop (IQCLSW), Policoro, Italy}, booktitle = {International Quantum Cascade Lasers School \& Workshop (IQCLSW), Policoro, Italy}, pages = {1 -- 2}, language = {en} } @inproceedings{GlaweSchulzGonzalezJuezetal., author = {Glawe, Christoph and Schulz, Falko T. and Gonzalez-Juez, Esteban D. and Schmidt, Heiko and Kerstein, Alan R.}, title = {ODTLES Simulations of Turbulent Flows through Heated Channels and Ducts}, series = {8th International Symposium on turbulence and shear flow phenomena (TSFP8), 28-30 August 2013, Poitiers, France, vol. 2}, booktitle = {8th International Symposium on turbulence and shear flow phenomena (TSFP8), 28-30 August 2013, Poitiers, France, vol. 2}, pages = {1 -- 6}, abstract = {A widely occurring problem in fluid dynamics either in engineering or e.g. hydrology is the turbulent transport through channels and ducts. ODTLES, a stochastic based multi-scale and multi-dimensional model, is a promising tool to describe these flows even including scalar proper- ties like temperature. We are quantifying the ability of ODTLES to describe the heated channel flow with respect to the Prandtl number and the flow through squared ducts with respect to the Reynolds number.}, language = {en} } @misc{JozefikKersteinSchmidtetal., author = {Jozefik, Zoltan and Kerstein, Alan R. and Schmidt, Heiko and Lyra, Sgouria and Kolla, Hemanth and Chen, Jackie H.}, title = {One-dimensional turbulence modeling of a turbulent counterflow flame with comparison to DNS}, series = {Combustion and Flame}, volume = {162}, journal = {Combustion and Flame}, number = {8}, issn = {0010-2180}, doi = {10.1016/j.combustflame.2015.05.010}, pages = {2999 -- 3015}, abstract = {The one-dimensional turbulence (ODT) model is applied to a reactant-to-product counterflow configuration and results are compared with DNS data. The model employed herein solves conservation equations for momentum, energy, and species on a one dimensional (1D) domain corresponding to the line spanning the domain between nozzle orifice centers. The effects of turbulent mixing are modeled via a stochastic process, while the Kolmogorov and reactive length and time scales are explicitly resolved and a detailed chemical kinetic mechanism is used. Comparisons between model and DNS results for spatial mean and root-mean-square (RMS) velocity, temperature, and major and minor species profiles are shown. The ODT approach shows qualitatively and quantitatively reasonable agreement with the DNS data. Scatter plots and statistics conditioned on temperature are also compared for heat release rate and all species. ODT is able to capture the range of results depicted by DNS. However, conditional statistics show signs of underignition.}, language = {en} } @misc{JozefikKersteinSchmidt, author = {Jozefik, Zoltan and Kerstein, Alan R. and Schmidt, Heiko}, title = {Simulation of shock-turbulence interaction in non-reactive flow and in turbulent deflagration and detonation regimes using one-dimensional turbulence}, series = {Combustion and Flame}, volume = {164}, journal = {Combustion and Flame}, issn = {0010-2180}, doi = {10.1016/j.combustflame.2015.10.035}, pages = {53 -- 67}, abstract = {The one-dimensional turbulence (ODT) methodology is extended to include an efficient compressible implementation and a model for capturing shock-induced turbulence is presented. Lignell et al. recently introduced a Lagrangian ODT implementation using an adaptive mesh. As the code operates in the incompressible regime (apart from constant-pressure dilatation) it cannot handle compressibility effects and their interactions with turbulence and chemistry. The necessary algorithmic changes to include compressibility effects are highlighted and our model for capturing shock- turbulence interaction is presented. To validate our compressible solver, we compare results for the Sod shock tube problem against a finite volume Riemannsolver. To validate our model for shock-turbulence interaction, we present comparisons for a non-reactive and a reactive case. First, results of a shock traveling from light (air) to heavy (SF6) with recheck have been simulated to match mixing width growth data of experiments and turbulent kinetic energy results from LES.Then, for one-step chemistry calibrated to represent an acetylene/airmixture we simulate the interaction of a shock wave with an expanding flame front, and compare results with 2D simulation (2D-sim) data for flame brush formation and ensuing deflagration-to-detonation transitions (DDT). Results for the Sod shock tube comparison show that the shock speed and profile are captured accurately. Results for the non-reactive shock-recheck problem show that interface growth at all simulated Mach numbers is captured accurately and that the turbulent kinetic energy agrees in order of magnitude with LES data. The reactive shock tube results show that the flame brush thickness compares well to 2D-sim data and that the approximate location and timing of the DDT can be captured. The known sensitivity of DDT characteristics to details of individual flow realizations, seen also in ODT, implies that model agreement can be quantified only by comparing flow ensembles, which are presently unavailable other than in an ODT run-to-run sensitivity study that is reported herein.}, language = {en} } @misc{GlaweSchmidtKersteinetal., author = {Glawe, Christoph and Schmidt, Heiko and Kerstein, Alan R. and Klein, Rupert}, title = {XLES Part I: Introduction to Extended Large Eddy Simulation}, series = {arXiv.org}, journal = {arXiv.org}, pages = {38}, abstract = {Direct numerical simulation (DNS), mostly used in fundamental turbulence research, is limited to low turbulent intensities due the current and future computer resources. Standard turbulence models, like RaNS (Reynolds averaged Navier-Stokes) and LES (Large Eddy Simulation), are applied to flows in engineering, but they miss small scale effects, which are frequently of importance, see e.g. the whole area of reactive flows, flows with apparent Prandtl or Schmidt number effects, or even wall bounded flows. A recent alternative to these standard approaches is the one-dimensional turbulence (ODT) model, which is limited to 1D sub-domains. In two papers we will provide a generalized filter strategy, called XLES (extended LES), including a formal theory (part I) and one special approach in the XLES family of models, called ODTLES (in part II (see Glawe et al. (2015))). ODTLES uses an ODT sub-grid model to describe all turbulent scales not represented by XLES, which leaves the larger scales to be simulated in 3D. This allows a turbulence modeling approach with a 3D resolution mainly independent of the turbulent intensity. Thus ODTLES is able to compute highly turbulent flows in domains of moderate complexity affordably and including the full range of turbulent and diffusive scales. The convergence of XLES to DNS is shown and the unconventional XLES advection approach is investigated in basic numerical tests. In part II, highly turbulent channel and duct flow results are discussed and show the future potential of XLES and ODTLES.}, language = {en} } @misc{GlaweSchmidtKersteinetal., author = {Glawe, Christoph and Schmidt, Heiko and Kerstein, Alan R. and Klein, Rupert}, title = {XLES Part II: From Extended Large Eddy Simulation to ODTLES}, series = {arXiv.org}, journal = {arXiv.org}, pages = {41}, abstract = {In turbulence research and flow applications, turbulence models like RaNS (Reynolds averaged Navier-Stokes) models and LES (Large Eddy Simulation) are used. Both models filter the governing flow equations. Thus a scale separation approach is introduced for modeling purposes with the large scales simulated using a numerical scheme while smaller scales are assumed to be less important and might be modeled more or less easily. Unfortunately small scales are frequently of big importance, e.g. in reactive flows, wall bounded flows, or flows with significant Prandtl or Schmidt number effects. Recent alternatives to these standard models are the class of models based on the one-dimensional turbulence (ODT) idea, like ODTLES. The ability of ODT to capture highly turbulent flows (recently up to Reτ=6×105) allows ODTLES to realize 3D resolutions basically independent of the turbulent intensity. In two papers we provide a formal theory and application of an innovative modeling strategy for highly turbulent flows in domains of moderate complexity: In part I (see Glawe et al. (2015)) a new general filtering approach, called XLES (extended LES), is introduced. Contrary to LES, XLES is based on 2D filtering of the governing equations, whereby additional small scale terms are interpreted numerically. In this work a new ansatz for the ODTLES model is introduced as one special approach in the XLES family of models by incorporating the ODT model into XLES. The ODT model introduces microstructures not captured by the XLES filtered equations. To illustrate the ODTLES model capabilities, turbulent channel and duct flows up to friction Reynolds number Reτ=10000 are studied.}, language = {en} } @inproceedings{GlaweSchmidtKerstein, author = {Glawe, Christoph and Schmidt, Heiko and Kerstein, Alan R.}, title = {ODTLES: A Multi-scale Ansatz for highly turbulent flows}, series = {15 The European turbulence conference, 25-28 august, 2015, Delft, The Netherland}, booktitle = {15 The European turbulence conference, 25-28 august, 2015, Delft, The Netherland}, pages = {2}, abstract = {We use ODTLES, a multi-dimensional extension of the One-Dimensional-Turbulence model (ODT). ODT describes turbulent advection on a 1D sub-domain using a stochastic process for turbulent advection. These 1D sub-domains are coupled to obtain a 3D approach. ODTLES is applied to channel flow. Preliminary results for the pdf of the wall shear stress are compared to DNS.}, language = {en} } @inproceedings{JozefikKersteinSchmidt, author = {Jozefik, Zoltan and Kerstein, Alan R. and Schmidt, Heiko}, title = {Incorporation of acceleration effects into the One-dimensional-turbulence model, with application to turbulent combustion and shock-turbulence interactions}, series = {15th European Turbulence Conference 2015 August 25-28th, 2015, Delft, The Netherlands}, booktitle = {15th European Turbulence Conference 2015 August 25-28th, 2015, Delft, The Netherlands}, pages = {2}, abstract = {One-dimensional turbulence (ODT) is a stochastic simulation in which 3D turbulence effects are captured on a notional 1D line of sight by introducing instantaneous spatial rearrangements (maps) that represent advection by notional turbulent eddies. These eddy events incorporate the possibility of kinetic-energy changes that are equal and opposite to changes of other forms of energy such as the gravitational potential energy change due to a rearrangement of a vertical density profile. This illustrates that motion aligned with an applied force, in this case gravitation g, can be associated with energy change. Using this principle, we 1) present a model of turbulence interaction with the dilatational acceleration caused by thermal expansion in flames and show results for a turbulent counterflow flame with comparison to DNS and 2) present a model for shock-induced turbulence and show results for mixing width growth in a shock tube with comparison to experiments.}, language = {en} } @misc{ChunSchmidtKucketal., author = {Chun, K. R. Julian and Schmidt, Boris and Kuck, Karl-Heinz and Andresen, Dietrich and Willems, Stefan and Spitzer, Stefan G. and Hoffmann, Ellen and Schumacher, Burghard and Eckardt, Lars and Seidl, Karlheinz and J{\"u}nger, Claus and Horack, Martin and Brachmann, Johannes and Senges, Jochen}, title = {Catheter ablation of atrial fibrillation in the young}, series = {Clinical Research in Cardiology}, volume = {102}, journal = {Clinical Research in Cardiology}, number = {6}, issn = {1861-0684}, doi = {10.1007/s00392-013-0553-6}, pages = {459 -- 468}, language = {en} } @misc{MovagharLinneOevermannetal., author = {Movaghar, Amirreza and Linne, Mark and Oevermann, Michael and Meiselbach, Falko T. and Schmidt, Heiko and Kerstein, Alan R.}, title = {Numerical investigation of turbulent-jet primary breakup using One-Dimensional Turbulence}, series = {International Journal of Multiphase Flow}, volume = {89}, journal = {International Journal of Multiphase Flow}, issn = {1879-3533}, pages = {241 -- 254}, abstract = {Primary breakup to form droplets at liquid surfaces is an important fundamental process to study as it determines the initial properties of the dispersed phase, which affect mixing rates, secondary breakup, droplet collisions, and flow separation within the dispersed flow region. Primary breakup can be regarded as one of the least developed model components for simulating and predicting liquid jet breakup. How- ever, it is of paramount importance in many technical applications, e.g. fuel injection in engines and spray painting. This paper presents a numerical investigation of primary breakup of a turbulent liquid jet in still air at standard conditions using the one-dimensional turbulence (ODT) modeling framework. ODT is a stochastic model that simulates turbulent flow evolution along a notional 1D line of sight by applying instantaneous maps to represent the effect of individual turbulent eddies on property profiles. An important feature of ODT is the resolution of all relevant scales, both temporal and spatial. The restriction to one spatial dimension in ODT permits affordable high resolution of interfacial and single-phase property gradients, which is key to capturing the local behavior of the breakup process and allows simulations at high Reynolds and Weber numbers that are currently not accessible to direct numerical simulations (DNS). This paper summarizes our extensions of the ODT model to simulate geometrically simple jet breakup problems, including representations of Rayleigh wave breakup, turbulent breakup, and shear-driven breakup. Each jet breakup simulation consists of a short temporal channel section to initialize a turbulent velocity profile at the nozzle exit followed by an adjacent jet section. The simulations are carried out for jet exit Reynolds number of 11,500, 23,000, 46,000 and 92,000 while the Weber number is varied within the range 102-107. We present results on breakup statistics including spatial locations of droplet release, droplet sizes and liquid core length. The results on primary breakup are compared to experimental results and models.}, language = {en} } @misc{EfimovaVargaMatuscheketal., author = {Efimova, Anastasia and Varga, Janos and Matuschek, Georg and Saraji-Bozorgzad, Mohammad R. and Denner, Thomas and Zimmermann, Ralf and Schmidt, Peer}, title = {Thermal Resilience of Imidazolium-Based Ionic Liquids—Studies on Short- and Long-Term Thermal Stability and Decomposition Mechanism of 1-Alkyl-3-methylimidazolium Halides by Thermal Analysis and Single-Photon Ionization Time-of-Flight Mass Spectrometry}, series = {Journal of Physical Chemistry B}, volume = {122}, journal = {Journal of Physical Chemistry B}, number = {37}, doi = {10.1021/acs.jpcb.8b06416}, pages = {8738 -- 8749}, abstract = {Ionic liquids are often considered as green alternatives of volatile organic solvents. The thermal behavior of the ionic liquids is relevant for a number of emerging large-scale applications at elevated temperature. Knowledge about the degradation products is indispensable for treatment and recycling of the used ionic liquids. The objective of this paper was an investigation of the short- and long-term stability of several 1-alkyl-3-methylimidazolium halides, determination of the degradation products, and the elucidation of their decomposition patterns and structure-stability relations. Short-term stability and mechanism of thermal degradation were investigated by a self-developed, innovative thermal analysis single-photon ionization time-of-flight mass spectrometry device with Skimmer coupling. The applied technology provides real-time monitoring of the forming species and allows tracing their change during the course of the decomposition. Therein, the almost fragment-free soft ionization with vacuum ultraviolet photons plays a crucial role. We have detected unfragmented molecules whose formation was only assumed by electron ionization. Nevertheless, the main decomposition products of the selected ionic liquids were alkyl imidazoles, alkenes, alkyl halides, and hydrogen halides. From the decomposition products, we have deduced the fragmentation patterns and discussed their interrelation with the length of the alkyl chain and the type of the halide anion. Our results did not suggest the evaporation of the investigated ionic liquids prior to their decomposition under atmospheric conditions. Long-term thermal stability and applicability were determined based on thermogravimetric analysis evaluated with a kinetic model. Thus, the time-dependent maximum operation temperature (MOT) for the respective ionic liquids has been calculated. As a rule, the short-term stability overestimates the long-term decomposition temperatures; the calculated MOT are significantly lower (at least 100 K) than the standardly obtained decomposition temperatures.}, language = {en} } @misc{LignellLansingerMedinaMendezetal., author = {Lignell, David O. and Lansinger, Victoria B. and Medina M{\´e}ndez, Juan Ali and Klein, Marten and Kerstein, Alan R. and Schmidt, Heiko and Fistler, Marco and Oevermann, Michael}, title = {One-dimensional turbulence modeling for cylindrical and spherical flows: model formulation and application}, series = {Theoretical and Computational Fluid Dynamics}, volume = {32}, journal = {Theoretical and Computational Fluid Dynamics}, number = {4}, issn = {0935-4964}, doi = {10.1007/s00162-018-0465-1}, pages = {495 -- 520}, abstract = {The one-dimensional turbulence (ODT) model resolves a full range of time and length scales and is computationally efficient. ODT has been applied to a wide range of complex multi-scale flows, such as turbulent combustion. Previous ODT comparisons to experimental data have focused mainly on planar flows. Applications to cylindrical flows, such as round jets, have been based on rough analogies, e.g., by exploiting the fortuitous consistency of the similarity scalings of temporally developing planar jets and spatially developing round jets. To obtain a more systematic treatment, a new formulation of the ODT model in cylindrical and spherical coordinates is presented here. The model is written in terms of a geometric factor so that planar, cylindrical, and spherical configurations are represented in the same way. Temporal and spatial versions of the model are presented. A Lagrangian finite-volume implementation is used with a dynamically adaptive mesh. The adaptive mesh facilitates the implementation of cylindrical and spherical versions of the triplet map, which is used to model turbulent advection (eddy events) in the one-dimensional flow coordinate. In cylindrical and spherical coordinates, geometric stretching of the three triplet map images occurs due to the radial dependence of volume, with the stretching being strongest near the centerline. Two triplet map variants, TMA and TMB, are presented. In TMA, the three map images have the same volume, but different radial segment lengths. In TMB, the three map images have the same radial segment lengths, but different segment volumes. Cylindrical results are presented for temporal pipe flow, a spatial nonreacting jet, and a spatial nonreacting jet flame. These results compare very well to direct numerical simulation for the pipe flow, and to experimental data for the jets. The nonreacting jet treatment overpredicts velocity fluctuations near the centerline, due to the geometric stretching of the triplet maps and its effect on the eddy event rate distribution. TMB performs better than TMA. A hybrid planar-TMB (PTMB) approach is also presented, which further improves the results. TMA, TMB, and PTMB are nearly identical in the pipe flow where the key dynamics occur near the wall away from the centerline. The jet flame illustrates effects of variable density and viscosity, including dilatational effects.}, language = {en} } @misc{KleinKersteinSchmidt, author = {Klein, Marten and Kerstein, Alan R. and Schmidt, Heiko}, title = {Stochastic modeling of transient boundary layers in high-Rayleigh-number thermal convection}, series = {25th International Congress of Theoretical and Applied Mechanics (ICTAM 20+1)}, journal = {25th International Congress of Theoretical and Applied Mechanics (ICTAM 20+1)}, pages = {2}, abstract = {One-dimensional turbulence (ODT) modeling is used to investigate the boundary layer in high-Rayleigh-number thermal convection for a notionally infinite horizontal layer of fluid. The model formulation distinguishes between turbulent advection, which is modeled by a stochastic process, and deterministic molecular diffusion to capture relevant vertical transport processes (including counter-gradient fluxes). For this study, statistical homogenization is applied to the two horizontal dimensions so that we use ODT as stand-alone tool. We show that the model yields mean and fluctuation temperature profiles that are in several respects consistent with available reference data. Furthermore, the profile of a surrogate for the fluctuation velocity is reminiscent of canonical wall turbulence.}, language = {en} } @misc{KleinSchmidtKerstein, author = {Klein, Marten and Schmidt, Heiko and Kerstein, Alan R.}, title = {Transition to the ultimate regime in a stochastic model for thermal convection with internal sources}, address = {IPAM Workshop: Transport and Mixing in Complex and Turbulent Flows (CTF2021), University of California, Los Angeles, CA, USA}, pages = {1}, language = {en} } @misc{KleinSchmidtKerstein, author = {Klein, Marten and Schmidt, Heiko and Kerstein, Alan R.}, title = {Transition to the ultimate regime in a stochastic model for radiatively driven turbulent convection}, series = {Verhandlungen der Deutschen Physikalischen Gesellschaft - BPCPPDYSOE21}, journal = {Verhandlungen der Deutschen Physikalischen Gesellschaft - BPCPPDYSOE21}, language = {en} } @misc{KleinSchmidtKerstein, author = {Klein, Marten and Schmidt, Heiko and Kerstein, Alan R.}, title = {Transition to the ultimate regime in a stochasticmodel for thermal convection with internal sources}, pages = {1}, abstract = {It is well established that heat transfer in turbulent Rayleigh-Bénard convection and angular momentum transfer in turbulent Taylor-Couette flow are similar in nature. This similarity manifests itself by isomorphic scaling laws for corresponding flow regimes. However, it is not clear at present if this similarity extends to flows with internal sources and different types of boundary conditions. Internal sources may occur, for example, due to radiative heating in dry or condensation in moist convection, or due to internal wave breaking and mean flow excitation in rotating Taylor-Couette-like flows. In this study, heat transfer in radiatively-driven turbulent Rayleigh-Bénard convection is investigated using the stochastic one-dimensional-turbulence model (ODT). A Boussinesq fluid of Prandtl number 1 is confined between two horizontal adiabatic no-slip walls that are located at z = 0 and H, respectively. The fluid is exposed to constant background gravity that points in vertical (-z) direction. A flow is driven by radiative heating from below yielding the local heating rate Q(z) = (P/l) exp(-z/l), where P is the prescribed mean total heat flux and l the absorption length that controls the thermal boundary layer thickness. ODT resolves all relevant scales of the flow, including molecular-diffusive scales, along a vertical one-dimensional domain, whereas stochastically sampled eddy events represent the effects of turbulent advection. ODT results reproduce and extrapolate available reference experiments of Lepot et al. (Proc. Natl. Acad. Sci. USA, 115, 2018, pp. 8937-8941) and Bouillaut et al. (J. Fluid Mech., 861, 2019, R5) in particular capturing the turbulent transition from the classical to the 'ultimate' regime. For these regimes, the exponent values in N u ∼ Ra^p scaling are found to be p ≈ 0.33 and p ≈ 0.55, respectively, in agreement with measured values. Joint probabilities of turbulent eddy size and location suggest that the regime transition is associated with a suppression of small-scale near-wall turbulent motions. The latter observation is found consistent with recent direct numerical simulations of heat transfer between permeable walls (Kawano et al., J. Fluid Mech., 914, 2021, A13).}, language = {en} } @misc{KleinSchmidtKerstein, author = {Klein, Marten and Schmidt, Heiko and Kerstein, Alan R.}, title = {Stochastic modeling of transient boundary layers in high-Rayleigh-number thermal convection, 25th International Congress of Theoretical and Applied Mechanics (ICTAM 20+1)}, pages = {1}, abstract = {One-dimensional turbulence (ODT) modeling is used to investigate the boundary layer in high-Rayleigh-number thermal convection for a notionally infinite horizontal layer of fluid. The model formulation distinguishes between turbulent advection, which is modeled by a stochastic process, and deterministic molecular diffusion to capture relevant vertical transport processes (including counter-gradient fluxes). For this study, statistical homogenization is applied to the two horizontal dimensions so that we use ODT as stand-alone tool. We show that the model yields mean and fluctuation temperature profiles that are in several respects consistent with available reference data. Furthermore, the profile of a surrogate for the fluctuation velocity is reminiscent of canonical wall turbulence.}, language = {en} } @misc{KleinFreireLignelletal., author = {Klein, Marten and Freire, Livia S. and Lignell, David O. and Kerstein, Alan R. and Schmidt, Heiko}, title = {Ein stochastischer Ansatz zur Modellierung fluktuierender Oberfl{\"a}chenfl{\"u}sse in turbulenten Grenzschichten}, series = {Kurzfassungen der Meteorologentagung DACH}, volume = {2022}, journal = {Kurzfassungen der Meteorologentagung DACH}, publisher = {Copernicus}, doi = {10.5194/dach2022-22}, pages = {1 -- 1}, abstract = {Im Konferenzbeitrag wird auf die Formulierung des stochastischen Modells eingegangen und gezeigt, dass neben Scherspannungen auch Druck-, Coriolis- und Auftriebskr{\"a}fte ber{\"u}cksichtigt werden k{\"o}nnen. Das Modell wird beispielhaft als unabh{\"a}ngiges, numerisches Werkzeug angewendet, um fluktuierende Oberfl{\"a}chenfl{\"u}sse in turbulenten Kanalstr{\"o}mungen sowie stabilen und konvektiven Grenzschichten zu untersuchen. Es werden sowohl glatte, als auch raue bzw. bewachsene (por{\"o}se) Oberfl{\"a}chen betrachtet. Anhand neuer Ergebnisse wird demonstriert, dass der Modellansatz in der Lage ist, Referenzdaten zufriedenstellend zu reproduzieren und extrapolieren. Daneben werden aktuelle Arbeiten zur Kopplung des stochastischen Modellansatzes mit Large-Eddy-Simulationen vorgestellt. Es wird gezeigt, dass die stochastische Modellierung oberfl{\"a}chennaher, subgitterskaliger Schwankungen in der Lage ist, wandnahe Turbulenzspektren zu reproduzieren und den filterbasierten Modellfehler bei ansonsten fester Gitteraufl{\"o}sung zu verringern.}, language = {de} } @misc{KersteinLignellSchmidtetal., author = {Kerstein, Alan R. and Lignell, David O. and Schmidt, Heiko and Starick, Tommy and Wheeler, Isaac and Behrang, Masoomeh}, title = {Using Hips As a New Mixing Model to Study Differential Diffusion of Scalar Mixing in Turbulent Flows}, series = {2021 AIChE Annual Meeting}, journal = {2021 AIChE Annual Meeting}, abstract = {Mixing two or more streams is ubiquitous in chemical processes and industries involving turbulent liquid or gaseous flows. Modeling turbulent mixing flows is complicated due to a wide range of time and length scales, and non-linear processes, especially when reaction is involved. On the other hand, in turbulent reacting flows, sub-grid scales need to be resolved accurately because they involve reactive and diffusive transport processes. Transported PDF methods use mixing models to capture the interaction in the sub-grid scales. Several models have been used with varying success. In this study, we present a novel model for simulation of turbulent mixing called Hierarchical Parcel Swapping (HiPS). The HiPS model is a stochastic mixing model that resolves a full range of time and length scales with the reduction in the complexity of modeling turbulent reacting flows. This model can be used as a sub-grid mixing model in PDF transport methods, as well as a standalone model. HiPS can be applied to transported scalars with variable Schmidt numbers to capture the effect of differential diffusion which is important for modeling scalars with low diffusivity like soot. We present an overview of the HiPS model, its formulation for variable Schmidt number flows, and then present results for evaluating the turbulence properties including the scalar energy spectra, the scalar dissipation rate, and Richardson dispersion. These model developments are an important step in applying HiPS to more complex flow configurations.}, language = {en} } @misc{BoehlerRosencrantzWolfetal., author = {B{\"o}hler, Stefan and Rosencrantz, Sophia and Wolf, Karina and Heinemann, Robert and Schmidt, Peer and Ganster, Johannes and B{\"u}sse, Thomas and Balko, Jens and Rosencrantz, Ruben R.}, title = {Active protease formulation in commodity polymers withstands melt processing into compounds and blown films}, series = {Materials Today Communications}, volume = {34}, journal = {Materials Today Communications}, issn = {2352-4928}, doi = {10.1016/j.mtcomm.2022.105018}, pages = {1 -- 9}, abstract = {Integrating enzymes into thermoplastic polymers is challenging due to their lack of robustness with respect to temperature and shear fields during conventional melt processing. In the present study, blown films from low-density polyethylene (LDPE) were prepared containing a technical protease from Bacillus sp. First, LDPE/protease compounds were produced followed by blown film extrusion, both processes at melt mass temperatures of 130 °C or higher. Enzyme activity was proven, both for the LDPE/protease compound and the blown film. The highest enzyme activity in the compound was determined for processing at 132 °C and a screw speed of 75 rpm. The influence of melt temperature and shear fields was studied in detail. Enzyme activities were determined for melt temperatures up to 160 °C and for screw speeds ranging from 75 to 300 rpm during compounding by twin-screw extrusion. The process was also applied for biobased and biodegradable polyesters, where similar protease activity after compounding was verified. Electron microscopy, X-ray diffraction, nuclear magnetic resonance spectroscopy and differential scanning calorimetry served to analyze components and morphology of the enzyme formulation used here. It is proposed that the porous morphology of the protease particles is beneficial for the enzyme to remain active after processing. Additionally, the polymer matrix surrounding the particles protects the protease at elevated temperatures, which can be attributed to thermal insulation. Thus, the right combination of a suited technical enzyme formulation with appropriate mild melt compounding conditions allows enzymes to be incorporated into thermoplastics and retain their activity. This opens the way to use the abundant biological functions of enzymes in thermoplastic applications.}, language = {en} } @misc{StarickBehrangLignelletal., author = {Starick, Tommy and Behrang, Masoomeh and Lignell, David O. and Schmidt, Heiko and Kerstein, Alan R.}, title = {Turbulent mixing simulation using the Hierarchical Parcel Swapping (HiPS) model}, series = {Proceedings of the Conference on Modelling Fluid Flow (CMFF'22)}, journal = {Proceedings of the Conference on Modelling Fluid Flow (CMFF'22)}, publisher = {Department of Fluid Mechanics, University of Technology and Economics}, address = {Budapest, Hungary}, isbn = {978-963-421-881-4}, pages = {1 -- 7}, language = {en} } @misc{LignellBehrangKersteinetal., author = {Lignell, David O. and Behrang, Masoomeh and Kerstein, Alan R. and Wheeler, Isaac and Starick, Tommy and Schmidt, Heiko}, title = {Investigation of turbulent mixing of scalars with arbitrary Schmidt numbers using the stochastic Hierarchical Parcel Swapping Model}, series = {77th Annual Meeting of the Division of Fluid Dynamics, November 24-26, 2024; Salt Lake City, Utah}, journal = {77th Annual Meeting of the Division of Fluid Dynamics, November 24-26, 2024; Salt Lake City, Utah}, publisher = {American Physical Society}, abstract = {Hierarchical Parcel Swapping (HiPS) is a stochastic model of turbulent mixing. HiPS is based on a binary tree structure consisting of nodes emanating from the top of the tree and terminating in parcels at the base of the tree containing fluid properties. Length scales decrease geometrically with increasing tree level, and corresponding time scales follow inertial range scaling. Turbulent mixing is modeled by swapping subtrees at different tree levels. Swaps involving single parcels result in micromixing that changes scalar states. Swaps are implemented as a Poisson process at rates corresponding to level time scales. HiPS is extended to simulation of multiple scalars with arbitrary diffusivities, considering transport in the inertial, viscous-advective, and inertial-diffusive ranges. Fundamental analysis of particle dispersion is presented with comparisons to theoretical results and DNS data in the inertial and viscous ranges. Scalar energy spectra are analysed in the three ranges and reproduce known scaling exponents. Scalar dissipation statistics are analysed and reproduce the experimental and theoretical lognormal distribution with negative skewness represented by a stretched-exponential function. DNS data are used to evaluate empirical coefficients, facilitating quantitative applications. The physical fidelity demonstrated with HiPS suggests its use as a low-cost subgrid model for coarse-grained flow simulation, for which parcel-pair mixing is a common treatment.}, language = {en} } @misc{StarickBehrangLignelletal., author = {Starick, Tommy and Behrang, Masoomeh and Lignell, David O. and Schmidt, Heiko and Kerstein, Alan R.}, title = {Turbulent mixing simulation using the Hierarchical Parcel-Swapping (HiPS) model}, series = {Technische Mechanik}, volume = {43}, journal = {Technische Mechanik}, number = {1}, issn = {0232-3869}, doi = {10.24352/UB.OVGU-2023-044}, pages = {49 -- 58}, abstract = {Turbulent mixing is an omnipresent phenomenon that permanently affects our everyday life. Mixing processes also plays an important role in many industrial applications. The full resolution of all relevant flow scales often poses a major challenge to the numerical simulation and requires a modeling of the small-scale effects. In transported Probability Density Function (PDF) methods, the simplified modeling of the molecular mixing is a known weak point. At this place, the Hierarchical Parcel-Swapping (HiPS) model developed by A.R. Kerstein [J. Stat. Phys. 153, 142-161 (2013)] represents a computationally efficient and novel turbulent mixing model. HiPS simulates the effects of turbulence on time-evolving, diffusive scalar fields. The interpretation of the diffusive scalar fields or a state space as a binary tree structure is an alternative approach compared to existing mixing models. The characteristic feature of HiPS is that every level of the tree corresponds to a specific length and time scale, which is based on turbulence inertial range scaling. The state variables only reside at the base of the tree and are understood as fluid parcels. The effects of turbulent advection are represented by stochastic swaps of sub-trees at rates determined by turbulent time scales associated with the sub-trees. The mixing of adjacent fluid parcels is done at rates consistent with the prevailing diffusion time scales. In this work, a standalone HiPS model formulation for the simulation of passive scalar mixing is detailed first. The generated scalar power spectra with forced turbulence shows the known scaling law of Kolmogorov turbulence. Furthermore, results for the PDF of the passive scalar, mean square displacement and scalar dissipation rate are shown and reveal a reasonable agreement with experimental findings. The described possibility to account for variable Schmidt number effects is an important next development step for the HiPS formulation. This enables the incorporation of differential diffusion, which represents an immense advantage compared to the established mixing models. Using a binary structure allows HiPS to satisfy a large number of criteria for a good mixing model. Considering the reduced order and associated computational efficiency, HiPS is an attractive mixing model, which can contribute to an improved representation of the molecular mixing in transported PDF methods.}, language = {en} } @misc{MedinaMendezKleinPeetersetal., author = {Medina M{\´e}ndez, Juan Ali and Klein, Marten and Peeters, Jurriaan W. R. and Schmidt, Heiko}, title = {Evaluating turbulent channel flows with rough walls : homogeneous roughness parameterization for use in a map-based turbulence model}, series = {International journal of heat and fluid flow}, volume = {117, Part B}, journal = {International journal of heat and fluid flow}, publisher = {Elsevier BV}, address = {Amsterdam}, doi = {10.1016/j.ijheatfluidflow.2025.110113}, pages = {1 -- 21}, abstract = {This work is focused on modeling the effects of homogeneous roughness on low-order velocity statistics in turbulent channel flows. Hydrodynamic effects due to the roughness are characterized on the basis of volume-averaging theory (VAT) and a discrete roughness element method. This theory exploits the homogeneous character of the roughness in order to reduce the complexity of the flow to its one-dimensional statistics. The formulated VAT-based roughness forcing is best suited for drag dominated surfaces. Turbulence modeling closure is achieved with a map-based turbulence model, the One-Dimensional Turbulence (ODT) model. This avoids the prescription of laws of the wall or other ad-hoc scalings, unlike in more traditional filter-based turbulence models. The modeling framework is applied on selected Reynolds number flows for likewise selected roughness topologies. Results are compared to direct numerical simulation (DNS) data available from the literature. Among others, model results are compared with those of a previously formulated parametric forcing approach (PFA) for roughness drag which involved a costly coefficient calibration linked to the roughness topology model. In ODT, the only calibration process required is the same one involved for the turbulence model parameters, i.e., similar to the ODT model application for smooth-wall flows. Despite all of the inherently implied shortcomings of a 1-D model, some appealing properties of ODT are discussed. Notably, the model is able to predict the roughness function, as well as the wall-normal profile of the Reynolds shear stress across the entire boundary layer thickness.}, language = {en} } @inproceedings{SchmidtEgbersRath, author = {Schmidt, J.-R. and Egbers, Christoph and Rath, H. J.}, title = {Experiments on the isothermal flow in wide spherical gaps}, language = {en} } @misc{BraudWallanderBussetal., author = {Braud, N. and Wallander, H.J. and Buß, L. and L{\"o}fstrand, M. and Blomqvist, J. and Berschauer, C. and Rodriguez, A. Morales and Kofoed, P.M. and Resta, A. and Krisponeit, J.-O. and Schmidt, T. and Lundgren, E. and Flege, J.I. and Falta, J. and Merte, L.R.}, title = {Growth, structure, and morphology of ultra-thin tin oxide phases forming on Pt₃Sn(111) single crystals upon exposure to oxygen}, series = {Surface science}, volume = {767}, journal = {Surface science}, publisher = {Elsevier BV}, address = {Amsterdam}, issn = {0039-6028}, doi = {10.1016/j.susc.2025.122927}, pages = {1 -- 8}, abstract = {Here we report an investigation of ultrathin tin oxide films on Pt3Sn(111) using low-energy electron microscopy (LEEM), microspot low-energy electron diffraction (𝜇-LEED), scanning tunneling microscopy (STM), surface X-ray diffraction (SXRD), and high-resolution X-ray photoelectron spectroscopy (XPS). Oxidation at ∼390-410 ◦C produces triangular, two-dimensional oxide islands that nucleate rapidly and exhibit self-limited lateral growth, attributed to limited Sn diffusion from the subsurface of the crystal. 𝜇-LEED shows that the initially formed (4 × 4) Sn oxide is subsequently converted to a more oxygen-rich (2 × 2𝑛) ''stripe'' phase. At 630 ◦C, enhanced Sn mobility enables a closed (4 × 4) film. The (2 × 2𝑛) phase is shown to consist of a (2 × 2) Sn lattice modulated by 1D stripe defects with spacings of 𝑛 = 4-6 atomic rows; LEED and SXRD measurements show diffraction features corresponding to this striped superstructure. The two oxides can be distinguished in XPS by their O 1s lineshapes: the (4 × 4) phase shows a clear doublet attributable to distinct O species, whereas the (2 × 2𝑛) phase exhibits a broader envelope consistent with a distribution of O coordination environments. The Sn 3d5∕2 spectra are similar for both phases, reflecting closely related Sn bonding motifs. The spectra are consistent with those of previous near-ambient-pressure XPS measurements, suggesting that the surface oxides forming under CO oxidation conditions are similar to those studied here.}, language = {en} }