Results 31 to 40 of about 202,648 (320)

Mechanism for Degradation of Nafion in PEM Fuel Cells from Quantum Mechanics Calculations [PDF]

, 2011
We report results of quantum mechanics (QM) mechanistic studies of Nafion membrane degradation in a polymer electrolyte membrane (PEM) fuel cell. Experiments suggest that Nafion degradation is caused by generation of trace radical species (such as OH ...
Goddard, William A., III, Liu, Wei-Guang, Merinov, Boris V., Sha, Yao, Shirvanian, Pezhman, Yu, Ted H.   +5 more
core   +1 more source

Isotopic fractionation in proteins as a measure of hydrogen bond length [PDF]

, 2015
If a deuterated molecule containing strong intramolecular hydrogen bonds is placed in a hydrogenated solvent it may preferentially exchange deuterium for hydrogen.
Athokpam, Bijyalaxmi, McKenzie, Ross H., Ramesh, Sai   +2 more
core   +2 more sources

Hydrogen Bonding Constrains Free Radical Reaction Dynamics at Serine and Threonine Residues in Peptides [PDF]

, 2014
Free radical-initiated peptide sequencing (FRIPS) mass spectrometry derives advantage from the introduction of highly selective low-energy dissociation pathways in target peptides.
Adamson J. T., Anh N. T., Anusiewicz I., Anusiewicz I., Bagheri-Majdi E., Bakhtiar R., Barlow C. K., Barlow C. K., Bogdanov B., Chamot-Rooke J., Chang Ho Sohn, Chen X., Chu I. K., Cooper H. J., Cui W., Daniel A. Thomas, Diedrich J. K., Diedrich J. K., Frison G., Fu A.-p., Gronert S., Hodyss R., Hopkinson A. C., Håkansson K., Iavarone A. T., Izgorodina E. I., J. L. Beauchamp, Jinshan Gao, Ke Y., Kim T.-Y., Kruger N. A., Kruger N. A., Lam A. K. Y., Laskin J., Laskin J., Laskin J., Lee J., Lee J., Lee M., Lee M., Little D. P., Ly T., Ly T., Ly T., Marzluff E. M., Marzluff E. M., Masterson D. S., Miao R., Moore B., Moore B. N., Osburn S., Paizs B., Petrotchenko E. V., Ryzhov V., Sawicka A., Sawicka A., Schaftenaar G., Senko M. W., Shen Y., Shi S. D. H., Shukla A. K., Simon M. D., Simons J., Siuti N., Skurski P., Sobczyk M., Sobczyk M., Sobczyk M., Sobczyk M., Sohn C. H., Sun Q., Sun Q., Syka J. E. P., Syrstad E., Syrstad E. A., Syrstad E. A., Tao Y., Thompson M. S., Tureček F., Tureček F., Tureček F., Tureček F., Tureček F., Wee S., Wee S., Wee S., Wendler K., Xia Y., Yin H., Zhang L., Zhang X., Zhang X., Zhao Y., Zhao Y., Zhao Y., Zubarev R. A., Zubarev R. A., Zubarev R. A., Zubarev R. A.   +98 more
core   +1 more source

Low-barrier hydrogen bonds in enzyme cooperativity

Nature, 2019
The underlying molecular mechanisms of cooperativity and allosteric regulation are well understood for many proteins, with haemoglobin and aspartate transcarbamoylase serving as prototypical examples1,2. The binding of effectors typically causes a structural transition of the protein that is propagated through signalling pathways to remote sites and ...
Dai, Shao-Bo, Funk, Lisa Marie, Rabe von Pappenheim, Fabian, Sautner, Viktor, Paulikat, Mirko, Schröder, Benjamin, Uranga, Jon, Mata, Ricardo A., Tittmann, Kai   +8 more
openaire   +4 more sources

A candidate LiBH4 for hydrogen storage: Crystal structures and reaction mechanisms of intermediate phases [PDF]

, 2005
First-principles calculation and x-ray diffraction simulation methods have been used to explore crystal structures and reaction mechanisms of the intermediate phases involved in dehydriding of LiBH4. LiBH4 was found to dehydride via two sequential steps:
Goddard, William A., III, Han, Young Soo, Kang, Jeung Ku, Kim, Se Yun, Muller, Richard P.   +4 more
core   +1 more source

Efficient urea electrosynthesis from carbon dioxide and nitrate via alternating Cu–W bimetallic C–N coupling sites

Nature Communications, 2023
Electrocatalytic urea synthesis is an emerging alternative technology to the traditional energy-intensive industrial urea synthesis protocol. Novel strategies are urgently needed to promote the electrocatalytic C–N coupling process and inhibit the side ...
Yilong Zhao, Yunxuan Ding, Wenlong Li, Chang Liu, Yingzheng Li, Ziqi Zhao, Yu Shan, Fei Li, Licheng Sun, Fusheng Li   +9 more
doaj   +1 more source

Structural Relevance of Intramolecular H-Bonding in Ortho-Hydroxyaryl Schiff Bases: The Case of 3-(5-bromo-2-hydroxybenzylideneamino) Phenol

Molecules, 2021
A new Schiff base compound, 3-(5-bromo-2-hydroxybenzylideneamino)phenol (abbreviated as BHAP) was synthesized and characterized by 1H- and 13C- nuclear magnetic resonance and infrared spectroscopies.
İsa Sıdır, Yadigar Gülseven Sıdır, Sándor Góbi, Halil Berber, Rui Fausto   +4 more
doaj   +1 more source

From ab initio quantum chemistry to molecular dynamics: The delicate case of hydrogen bonding in ammonia [PDF]

, 2003
The ammonia dimer (NH3)2 has been investigated using high--level ab initio quantum chemistry methods and density functional theory (DFT). The structure and energetics of important isomers is obtained to unprecedented accuracy without resorting to ...
Boese, A. Daniel, Chandra, Amalendu, Martin, Jan M. L., Marx, Dominik   +3 more
core   +2 more sources

On the electronic nature of low-barrier hydrogen bonds in enzymatic reactions [PDF]

Proceedings of the National Academy of Sciences, 1998
The electronic nature of low-barrier hydrogen bonds (LBHBs) in enzymatic reactions is discussed based on combined low temperature neutron and x-ray diffraction experiments and on high levelab initiocalculations by using the model substrate benzoylacetone.
Schiøtt, Birgit, Iversen, B.B., Madsen, G.K.H., Larsen, F.K., Bruice, T.C.   +4 more
openaire   +3 more sources

Lancifodilactone G : insights about an unusually stable enol [PDF]

, 2008
From quantum mechanics calculations we confirm that the naturally occurring enol lancifodilactone G is stable over the keto form (by 2.6 kcal/mol in water), the only known stable aliphatic enol (devoid of conjugated or bulky aromatics and lacking a 1,3 ...
Chenoweth, D. M., Chenoweth, K., Goddard, W. A., III   +2 more
core   +1 more source