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871.
Derek R. Boyd Peter B. Coulter W.James Hamilton W. Brian Jennings Valerie E. Wilson 《Tetrahedron letters》1984,25(21):2287-2288
The results of a kinetic study of the thermal isomerization of oxaziridines derived from -substituted C-arylaldimines and C-diarylketimines to the isomeric nitrones is reported. 相似文献
872.
873.
Simmons MY Hamilton AR Pepper M Linfield EH Rose PD Ritchie DA 《Physical review letters》2000,84(11):2489-2492
A detailed investigation of the metallic behavior in high-quality GaAs-AlGaAs two-dimensional hole systems reveals the presence of quantum corrections to the resistivity at low temperatures. Despite the low density ( r(s)>10) and high quality of these systems, both weak localization (observed via negative magnetoresistance) and weak hole-hole interactions (giving a correction to the Hall constant) are present in the so-called metallic phase where the resistivity decreases with decreasing temperature. If these quantum corrections persist down to T = 0, the results suggest that even at high r(s) there is no metallic phase in two dimensions. 相似文献
874.
JM Chatterjee M Saha Sarkar S Bhattacharya P Banerjee S Sarkar RP Singh S Murulithar RK Bhowmik 《Pramana》2001,57(1):165-169
High-spin states of 95,97Mo (Z=42, N=53,55) nuclei have been investigated through 82Se(18O, xn) reaction at Eb=60 MeV. The level scheme in 95Mo has been observed upto ≏ 10 MeV in the present experiment. The level structure shows mainly single particle character.
In 97Mo, the ground state level sequence has been extended to ≏ 4.5 MeV while the previous information had been up to 2.4 MeV.
A negative parity band built on 1437 keV (11/2−) excited state has been extended to 5.5 MeV. The structure seems to show a coexistence of single particle and collective
modes of excitation. Properties of both the nuclei have been compared with shell model calculations using OXBASH. 相似文献
875.
The nucleus 30 65 Zn was studied using the 52Cr(16O, 2pn)65Zn reaction at a beam energy of 65 MeV. The level scheme is extended up to an excitation energy of 10.57 MeV for spin-parity (41/2?) with several newly observed transitions placed in it. 相似文献
876.
Roesky HW Stasch A Hatop H Rennekamp C H Hamilton D Noltemeyer M Schmidt HG 《Angewandte Chemie (International ed. in English)》2000,39(1):171-173
A facile synthesis utilizing tetra-n-butylammonium hydrogen difluoride and Group 13 alkyl compounds leads to the soluble salts 1 - 4. Compound 1 is the smallest difluoro-diorganoaluminate so far characterized. The corresponding gallium and indium derivatives 3 and 4 are not sensitive to moisture. 相似文献
877.
878.
Allen ZA Astone P Baggio L Busby D Bassan M Blair DG Bonaldi M Bonifazi P Carelli P Cerdonio M Coccia E Conti L Cosmelli C Crivelli Visconti V D'Antonio S Fafone V Falferi P Fortini P Frasca S Hamilton WO Heng IS Ivanov EN Johnson WW Kingham M Locke CR Marini A 《Physical review letters》2000,85(24):5046-5050
We report the initial results from a search for bursts of gravitational radiation by a network of five cryogenic resonant detectors during 1997 and 1998. This is the first significant search with more than two detectors observing simultaneously. No gravitational wave burst was detected. The false alarm rate was lower than 1 per 10(4) yr when three or more detectors were operating simultaneously. The typical threshold was H approximately 4x10(-21) Hz-1 on the Fourier component at approximately 10(3) Hz of the gravitational wave strain amplitude. New upper limits for amplitude and rate of gravitational wave bursts have been set. 相似文献
879.
Tomáš Tyc Brett Hamilton Barry C. Sanders William D. Oliver 《Foundations of Physics》2007,37(7):1027-1048
Whereas boson coherent states with complex parametrization provide an elegant, and intuitive representation, there is no counterpart
for fermions using complex parametrization. However, a complex parametrization provides a valuable way to describe amplitude
and phase of a coherent beam. Thus we pose the question of whether a fermionic beam can be described, even approximately,
by a complex-parametrized coherent state and define, in a natural way, approximate complex-parametrized fermion coherent states.
Then we identify four appealing properties of boson coherent states (eigenstate of annihilation operator, displaced vacuum
state, preservation of product states under linear coupling, and factorization of correlators) and show that these approximate
complex fermion coherent states fail all four criteria. The inapplicability of complex parametrization supports the use of
Grassman algebras as an appropriate alternative.
相似文献
880.