Results 31 to 40 of about 107,082 (295)

Inverse Solvent Isotope Effects in Enzyme-Catalyzed Reactions

Molecules, 2020
Solvent isotope effects have long been used as a mechanistic tool for determining enzyme mechanisms. Most commonly, macroscopic rate constants such as kcat and kcat/Km are found to decrease when the reaction is performed in D2O for a variety of reasons ...
Patrick L. Fernandez, Andrew S. Murkin
doaj   +1 more source

Isotope Effects as New Proxies for Organic Pollutant Transformation

CHIMIA, 2014
Assessing the pathways and rates of organic pollutant transformation in the environment is a major challenge due to co-occurring transport and degradation processes. Measuring changes of stable isotope ratios (e.g. 13C/12C, 2H/1H, 15N/14N) in individual
Thomas B. Hofstetter, Jakov Bolotin, Sarah G. Pati, Marita Skarpeli-Liati, Stephanie Spahr, Reto S. Wijker   +5 more
doaj   +1 more source

Ab initio simulations of the kinetic properties of the hydrogen monomer on graphene

, 2010
The understanding of the kinetic properties of hydrogen (isotopes) adatoms on graphene is important in many fields. The kinetic properties of hydrogen-isotope (H, D and T) monomers were simulated using a composite method consisting of density functional ...
Allouche A., Ao Z. M., Balog R., Baouche S., Baroni S., Blöchl P. E., Bostwick A., Boukhvalov D. W., Boukhvalov D. W., Casolo S., Coey J. M. D., Dennis P. A., Duplock E. J., Elias D. C., Eyring H., Ferro Y., Ferro Y., Ferro Y., Giannozzi P., Guisinger N. P., Henkelman G., Herrero C. P., Hornekær L., Hornekær L., Hänggi P., Kerwin J., Kohn W., Lachawiec A. J., Lebégue S., Liang Feng Huang, Luo Z., Mei Yan Ni, Methfessel M., Miura Y., Morris J., Mounet N., Perdew J. P., Pollak E., Roman T., Ryu S., Shytov A. V., Sofo J. O., Sundell P. G., Toyoura K., Vanderbilt D., Vineyard G. H., Wang Huai Zhou, Xiao Hong Zheng, Yong Gang Li, Zecho T., Zecho T., Zhi Zeng   +51 more
core   +1 more source

Extreme enrichment in atmospheric 15N15N. [PDF]

, 2017
Molecular nitrogen (N2) comprises three-quarters of Earth's atmosphere and significant portions of other planetary atmospheres. We report a 19 per mil (‰) excess of 15N15N in air relative to a random distribution of nitrogen isotopes, an enrichment that ...
Fischer, Tobias P, Haslun, Joshua A, Hu, Huanting, Kohl, Issaku E, Li, Shuning, Ostrom, Nathaniel E, Schauble, Edwin A, Yeung, Laurence Y, Young, Edward D   +8 more
core   +1 more source

Evaluation of Poorly Soluble Drugs’ Dissolution Rate by Laser Scattering in Different Water Isotopologues

Molecules, 2021
The most important task in the design of dosage forms is to modify the pharmaceutical substances structure in order to increase solubilization, targeted delivery, controlled rate of drug administration, and its bioavailability.
Elena V. Uspenskaya, Tatiana V. Pleteneva, Ilaha V. Kazimova, Anton V. Syroeshkin   +3 more
doaj   +1 more source

Illuminating hydrological processes at the soil-vegetation-atmosphere interface with water stable isotopes [PDF]

, 2016
Funded by DFG research project “From Catchments as Organised Systems to Models based on Functional Units” (FOR 1Peer reviewedPublisher PDFPublisher ...
Adomako, Ali, Allen, Allen, Allison, Allison, Allison, Ambach, Anderson, Araguás-Araguás, Asano, Asbjornsen, Bachmann, Barbeta, Bariac, Barnes, Bayala, Bengtsson, Berman, Berry, Bertrand, Beven, Beyer, Beyer, Bijoor, Birkel, Birkel, Blume, Botter, Boutton, Bowen, Bowen, Bowen, Brandes, Braud, Brinkmann, Brodersen, Brooks, Brooks, Brooks, Brooks, Burger, Cheng, Clark, Comas-Bru, Coplen, Craig, Craig, Craig, Cui, Cui, Cui, Dai, Dansgaard, Darling, David, Dawson, Dawson, DeWalle, DeWalle, DeWalle, Dincer, Dubbert, Dubbert, Dubbert, Dutton, Eggemeyer, Ehleringer, Ehleringer, Eichler, Ellsworth, Ellsworth, Emerman, Evaristo, Fairburn, Ferretti, Fujimoto, Gaj, Gangi, Garvelmann, Gat, Gat, Gazis, Gehrels, Geris, Gibson, Goldsmith, Gonfiantini, Gonfiantini, Gonfiantini, Good, Gralher, Hannes Leistert, Hao, Hargreaves, Herbstritt, Holland, Hopmans, Horita, Horton, Hrachowitz, Hsieh, Hu, Huang, Hursh, Ikawa, Ingraham, Jackson, Jasechko, Jia, Kabeya, Kabeya, Katharina Gimbel, Kelln, Kendall, Kendall, Kendall, Kim, Klaus, Klaus, Kline, Koeniger, Koeniger, Koeniger, Koeniger, Komor, Kool, Kudo, Kulmatiski, Kulmatiski, Kurz-Besson, Lai, Landon, Landon, Landwehr, Landwehr, Le Roux, Leaney, Lee, Lee, Leibundgut, Leng, Leopoldo, Lin, Lindström, Liu, Liu, Liu, Liu, Lutz, M., Majoube, Mali, Mali, Maloszewski, Markus Weiler, Mathieu, Matthias Sprenger, McCole, McDonnell, McDonnell, McDonnell, McDonnell, McDonnell, McGuire, McGuire, McGuire, McGuire, McGuire, McMillan, Meinzer, Meinzer, Meißner, Mensforth, Moore, Moreira, Mueller, Murad, Murad, Muñoz-Villers, Münnich, Münnich, O'Driscoll, Oerter, Ogle, Ogle, Ohte, Orlowski, Orlowski, Orlowski, Orlowski, Oshun, Palacio, Pangle, Pangle, Parnell, Penman, Penman, Penna, Peralta-Tapia, Phillips, Pionke, Revesz, Richards, Rinaldo, Robertson, Rodhe, Rong, Rose, Rossatto, Rossatto, Rothfuss, Rothfuss, Rozanski, Sami, Saxena, Schlaepfer, Scholl, Schwendenmann, Seiler, Simonin, Simpson, Singleton, Snyder, Soderberg, Song, Song, Soulsby, Sprenger, Sprenger, Sprenger, Sprenger, Stanhill, Stewart, Stumpp, Stumpp, Stumpp, Stumpp, Stumpp, Stumpp, Stumpp, Sun, Sutanto, Swaffer, Tang, Tetzlaff, Thomas, Timbe, Timbe, Treydte, Twining, Vanderborght, Vereecken, Vitvar, Vogel, Volkmann, Volkmann, Volkmann, Wang, Wang, Wang, Wang, Wassenaar, Wei, Welker, Wenner, Wenninger, Wershaw, Wessolek, West, West, White, White, Williams, Windhorst, Windhorst, Xu, Yeh, Zhang, Zhang, Zhang, Zhou, Zhou, Zhou, Zhu, Zimmermann, Zimmermann, Zimmermann   +287 more
core   +1 more source

Development of an advanced on-line position-specific stable carbon isotope system and application to methyl tert-butyl ether [PDF]

, 2009
We present an advanced system for on-line position-specific carbon isotope analysis. The main limitation of on-line intramolecular isotope ratio measurements has been that optimal pyrolytic fragments are obtained mostly at temperatures where the analyte ...
Abelson, Barrie, Barth, Benson, Coplen, Corso, Corso, Corso, Daly, Dempster, Dias, Elsner, Elsner, Fischer, Gray, Hall, Hall, Harrington, Hayes, Hirschorn, Huang, Hunkeler, Jasper, Jeffrey, Kolhatkar, Kuder, Mancini, Mariotti, Matthews, Meckenstock, Meier-Augenstein, Meier-Augenstein, Merritt, Miller, Monson, Morrison, O'Sullivan, Poulson, Richnow, Rosell, Sacks, Sano, Schmidt, Schmidt, Schüth, Slater, Slater, Slater, Smallwood, Somsamak, Somsamak, Vogler, Wang, Wolyniak, Wolyniak, Yamada, Zwank   +56 more
core   +1 more source

Thallium Isotope Fractionation During Magma Degassing: Evidence From Experiments and Kamchatka Arc Lavas

Geochemistry, Geophysics, Geosystems, 2021
Thallium (Tl) isotope ratios are an emerging tool that can be used to trace crustal recycling processes in arc lavas and ocean island basalts (OIBs). Thallium is a highly volatile metal that is enriched in volcanic fumaroles, but it is unknown whether ...
Sune G. Nielsen, Yunchao Shu, Bernard J. Wood, Jerzy Blusztajn, Maureen Auro, C. Ashley Norris, Gerhard Wörner   +6 more
doaj   +1 more source

Quantum-instanton evaluation of the kinetic isotope effects [PDF]

The Journal of Chemical Physics, 2005
A general quantum-mechanical method for computing kinetic isotope effects is presented. The method is based on the quantum-instanton approximation for the rate constant and on the path-integral Metropolis–Monte Carlo evaluation of the Boltzmann operator matrix elements.
Vanicek, Jiri, Miller, William H., Castillo, Jesus F., Aoiz, F. Javier   +3 more
openaire   +4 more sources

Nitrogen isotopic fractionation during abiotic synthesis of organic solid particles

, 2014
The formation of organic compounds is generally assumed to result from abiotic processes in the Solar System, with the exception of biogenic organics on Earth.
Bernard, Sylvain, Carrasco, Nathalie, Fleury, Benjamin, Kuga, Maïa, Marrocchi, Yves, Marty, Bernard, Rigaudier, Thomas, Tissandier, Laurent   +7 more
core   +3 more sources