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81.
Romer S Behzadi B Fasel R Ernst KH 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(14):4149-4154
Two-dimensional lattice structures formed by racemic tartaric acid on a single crystalline Cu(110) surface have been studied and compared with the enantiopure lattices. At low coverage, the doubly deprotonated bitartrate species is separated into two-dimensional conglomerates showing opposite enantiomorphism. At higher coverage, however, a singly deprotonated monotartrate species forms a heterochiral, racemic crystal lattice. While the enantioseparated bitartrate system undergoes decomposition at the same temperature as the enantiopure system, the racemic monotartrate lattice has a lower thermal stability than the enantiopure lattice of identical periodicity and surface density. At monolayer saturation coverage, the pure enantiomers form a denser lattice than the racemate. This is in contrast to the three-dimensional tartaric acid crystals, where the racemate crystallizes in a lattice of higher density, which is also more thermally stable than the enantiopure tartaric acid crystals. 相似文献
82.
Armstrong DS Arvieux J Asaturyan R Averett T Bailey SL Batigne G Beck DH Beise EJ Benesch J Bimbot L Birchall J Biselli A Bosted P Boukobza E Breuer H Carlini R Carr R Chant N Chao YC Chattopadhyay S Clark R Covrig S Cowley A Dale D Davis C Falk W Finn JM Forest T Franklin G Furget C Gaskell D Grames J Griffioen KA Grimm K Guillon B Guler H Hannelius L Hasty R Hawthorne Allen A Horn T Johnston K Jones M Kammel P Kazimi R King PM Kolarkar A Korkmaz E Korsch W Kox S Kuhn J Lachniet J Lee L 《Physical review letters》2005,95(9):092001
We have measured parity-violating asymmetries in elastic electron-proton scattering over the range of momentum transfers 0.12 < or =Q2 < or =1.0 GeV2. These asymmetries, arising from interference of the electromagnetic and neutral weak interactions, are sensitive to strange-quark contributions to the currents of the proton. The measurements were made at Jefferson Laboratory using a toroidal spectrometer to detect the recoiling protons from a liquid hydrogen target. The results indicate nonzero, Q2 dependent, strange-quark contributions and provide new information beyond that obtained in previous experiments. 相似文献
83.
Cemil Ibis Sibel Sahinler Ayla Şenol Yavuz Hatice Asar Funda Özkök Hakan Bahar 《Phosphorus, sulfur, and silicon and the related elements》2018,193(6):358-362
In this study, S-, S,S- and S,O-substituted novel nitrodiene compounds were synthesized. Cyclization products were formed when difunctional nucleophiles were used. The stereoisomerism of a heterocyclic nitrodiene is discussed with the help of XRD studies. The structures of all compounds were characterized by spectroscopic methods (FT-IR, 1H NMR, 13C NMR, 19F NMR, MS) and microanalysis. 相似文献
84.
85.
Ucar Asuman Findik Mukerrem Kuzu Muslum Pehlivanoglu Suray Sayin Ulku Sayin Zafer Akgemci Emine Guler 《Research on Chemical Intermediates》2021,47(2):533-550
Research on Chemical Intermediates - Metal complexes of thiosemicarbazones have been receiving considerable attention in biological applications such as antimicrobial and anticancer therapies. In... 相似文献
86.
87.
Bahar J. Lghazi Y. Youbi B. Ait Himi M. Bimaghra I. 《Journal of Solid State Electrochemistry》2021,25(6):1889-1900
Journal of Solid State Electrochemistry - A comparative study of the electrochemical deposition of cobalt on tin-doped indium oxide (ITO) substrate was carried out using electrochemical techniques... 相似文献
88.
Abstract In this paper, the full wave expressions for the radar scattering cross sections for two-dimensional random rough surfaces are obtained. The rough-surface height/slope correlations are accounted for in this analysis. Analytical and numerical comparisons of the full wave solution with the small perturbation and physical optics solutions are made for isotropic, homogeneous random rough surfaces with Gaussian probability density function. The full wave results are also compared with experimental results. 相似文献
89.
Bahar Yeniad N. Oruç Köklükaya Hemantkumar Naik M. W. Martin Fijten Cor E. Koning Andreas Heise 《Journal of polymer science. Part A, Polymer chemistry》2013,51(1):84-93
Homo and copolymers were synthesized from enantionpure (R)‐ and (S)‐1‐(4‐vinylphenyl)ethanol by reversible addition‐fragmentation chain transfer polymerization. The polymerization conditions were optimized resulting in dioxane as the preferred reaction solvent. First‐order polymerization kinetics and well‐defined enantiopure homopolymers with low dispersities were obtained. In agreement with their enantiomeric composition, the (R) and (S)‐polymers gave opposite optical rotation of light. Polymer analogous esterification of the chiral hydroxy groups catalyzed by enantioselective Candida antarctica Lipase B was strongly (R)‐selective. Esterification on the homopolymer and copolymers could be achieved to a maximum of around 50 %. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
90.
Domain swapping proceeds via complete unfolding: a 19F- and 1H-NMR study of the Cyanovirin-N protein
Liu L Byeon IJ Bahar I Gronenborn AM 《Journal of the American Chemical Society》2012,134(9):4229-4235
Domain swapping creates protein oligomers by exchange of structural units between identical monomers. At present, no unifying molecular mechanism of domain swapping has emerged. Here we used the protein Cyanovirin-N (CV-N) and (19)F-NMR to investigate the process of domain swapping. CV-N is an HIV inactivating protein that can exist as a monomer or a domain-swapped dimer. We measured thermodynamic and kinetic parameters of the conversion process and determined the size of the energy barrier between the two species. The barrier is very large and of similar magnitude to that for equilibrium unfolding of the protein. Therefore, for CV-N, overall unfolding of the polypeptide is required for domain swapping. 相似文献