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51.
Görgen JJ Comfort JR Tinsley JR Averett T DeKorse J Franklin B Ritchie BG Kyle G Klein A Berman B Burleson G Cranston K Faucett JA Jarmer JJ Knudson JN Penttilä S Tanaka N Brinkmöller B Dehnhard D Yen YF Hoibråten S Breuer H Flanders BS Khandaker MA Naples DL Zhang D Barlett ML Hoffmann GW Purcell M 《Physical review letters》1991,66(17):2193-2196
52.
Marcelo Samuel Berman 《International Journal of Theoretical Physics》1992,31(8):1451-1454
We discuss various possible scenarios where 2q, where stands for the density parameter andq for the deceleration parameter. We further estimate the corrections necessary when a variable cosmological constant is considered in the theory. 相似文献
53.
Morari C Bogdan D 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(8):1881-1886
Ab initio and vibrational self-consistent field (VSCF) computations are used to investigate the vibrational normal coordinates of the protonated Schiff base (PSB) 4-cis-gamma,eta-dimethyl-C9H9 NH2+. The ground and the first excited states are investigated. Both harmonic and anharmonic frequencies for the first three overtones of the ground and first excited states are reported. Special attention is payed to the discussion of the normal coordinates modes that involve the central C=C bond which plays a significant role in the isomerization process. 相似文献
54.
[reaction: see text] Glycosyl phosphates can be readily accessed on a solid support via a three-step procedure from support-bound glycals. These resin-bound glycosyl phosphates were successfully used as glycosylating agents for coupling with a series of nucleophiles. The stereochemical outcome of disaccharide formation was dependent on the nature of the linker connecting the saccharide to the polymer. Interestingly, other glycosyl donors such as thioglycosides and trichloroacetimidates did not exhibit such a dependence, indicating a different reaction mechanism for glycosylation. 相似文献
55.
The formation of the XeF+ ion by ion-molecule reaction has been observed in an ionized mixture of Xe and NF3 by ion cyclotron resonance mass spectrometry. The excited 2P state of the xenon ion has unambiguously been identified as the major precursor by photoionization mass spectrometry. The NF+3 ion makes an additional minor contribution. Evidence suggests that the excited 2P xenon ion radiatively decays to the 2P ground state on the time scale of the experiment. The transition probability deduced for this dipole forbidden emission, 18 ± 4 s?1, is in good agreement with the theoretical value of 21 s?1 for the sum of the magnetic dipole and electric quadrupole transition rates. 相似文献
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Maja Ponikvar-Svet Diana N. Zeiger Loryn R. Keating Joel F. Liebman 《Structural chemistry》2013,24(6):2101-2114
The contents of issues 1 and 2 for the calendar year 2013 are summarized in the current review of the journal Structural Chemistry. In addition, a brief thermochemical commentary is added to the summary of each paper. 相似文献
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