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91.
HongBingJI DuGuiHE JunSONG YuQIAN 《中国化学快报》2004,15(10):1241-1244
Clean liquid oxidation of aldehydes can be accomplished using solid catalyst in the presence of molecular oxygen at room temperature, which is a valuable alternative to traditional counterparts. 相似文献
92.
本文介绍FAB质谱的原理、功能和优点。综述了FAB机理,讨论了影响FAB谱的因素。归纳了FAB法在金属有机配合物研究中的应用。 相似文献
93.
Summary In this paper, we continue earlier works of one of the authors on vague convergence of the sequence
k,n=
k+1 *...*
n, where
n is a sequence of probability measures on semigroups or groups. Typical results in this paper are: Theorem. Let S be a locally compact noncompact second countable group such that
being the support of a probability measure on S. Suppose there exists an open set V with compact closure such that x
–1
Vx=V for every xS. Then for all compact sets K, sup{
n
(Kx): xS0 as n. Theorem. Let S be an at most countable discrete group. Let
n be a sequence of probability measures on S. Then for all nonnegative integers k, the sequence
k,n converges vaguely to some probability measure if and only if there exists a finite subgroup G such that the series
and for any proper subgroup G of G and any choice of elements gn in S, the series
. A sufficient condition for the vague convergence of the sequence
k,n to a probability measure is that (i) there exists a finite subgroup G such that
and (ii)
n(e)>s>0 for all n, e being the identity.The author was supported by NSF grant MCS77-03639 相似文献
94.
ZENG ChunHua WANG Hua & HU JianHang Faculty of Science Kunming University of Science Technology Kunming China Province Engineering Research Center of Industrial Energy Conservation New Technology 《中国科学:物理学 力学 天文学(英文版)》2011,(8)
In this paper, we investigate the escape of Brownian particles and stochastic resonance (SR) with low-temperatures quantum fluctuations by using the quantum Smoluchowski equations at low-temperature. Two specific examples have been considered: one is the example of bistable system, and the other is the example of metastable system. The explicit expressions of the mean-first passage time (MFPT) and signal-to-noise ratio (SNR) for both specific examples are obtained, respectively. Based on the numerical compu... 相似文献
95.
1.The Journal Analysis in Theory and Applications(abbr.ATA used to be Approximation Theory and its Applications in1984-2002)publishes originalpapers 相似文献
96.
JIA HongSheng JIA XiaoPeng XU Yue WAN LianRu JIE KaiKai & MA HongAn State Key Laboratory of Superhard Materials Jilin University Changchun China Test Science Experiment Center Changchun 《中国科学:物理学 力学 天文学(英文版)》2011,(1)
Polycrystalline diamond compacts (PDC) were synthesized using diamond powder of average crystal size 3-20 μm by the Ni 70 Mn 25 Co 5 alloy infiltration technique at high temperature and high pressure (HPHT).The surface residual stress of polycrystalline diamond (PCD) layer was measured using micro-Raman spectroscopy with hydrostatic stress model and X-ray diffraction (XRD).Measurements of the stress levels of PCDs show that the residual compressive stresses range from 0.12 to 0.22 GPa,which increase with th... 相似文献
97.
Guangzhou Lu Limin Yang Liqiang Wu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):403-408
Abstract A simple, inexpensive, and efficient one-pot synthesis of 2-arylthiazoline derivatives under solvent-free conditions using a catalytic amount of 1-butyl-3-methylimidazolium tribromide with excellent product yields is reported. This methodology provides easy, quantitative access to various 2-arylthiazoline derivatives, using environmentally benign 1-butyl-3-methylimidazolium tribromide as a catalyst. 相似文献
98.
99.
HAN Tao LU XiaoChun WANG Xue RAO YongNan ZOU DeCai YANG JianFei & WU YangYang National Time Service Center Xi'an China Key Laboratory of Precision Navigation Timing Technology Chinese Academy of Sciences Graduate University of the Chinese Academy of Sciences Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(6)
With the development of Global Navigation Satellite System (GNSS),the idea of GNSS interoperability is born and has become the focus of study in the field of satellite navigation.The popularity for GNSS to augment the interoperability with the existing ones necessitates the study of the assessment algorithm of this idea.In this paper,an assessment algorithm for interoperability comprehensive benefits based on the differential equation dynamical system is discussed.There are two important aspects in GNSS tha... 相似文献
100.
A large-scale antenna system(LSAS) with digital beamforming is expected to significantly increase energy efficiency(EE) and spectral efficiency(SE) in a wireless communication system. However, there are many challenging issues related to calibration, energy consumption, and cost in implementing a digital beamforming structure in an LSAS. In a practical LSAS deployment, hybrid digital-analog beamforming structures with active antennas can be used. In this paper, we investigate the optimal antenna configuration in an N × M beamforming structure, where N is the number of transceivers, M is the number of active antennas per transceiver, where analog beamforming is introduced for individual transceivers and digital beamforming is introduced across all N transceivers. We analyze the green point, which is the point of maximum EE on the EE-SE curve, and show that the log-scale EE scales linearly with SE along a slope of-lg2/N. We investigate the effect of M on EE for a given SE value in the case of fixed NM and independent N and M. In both cases, there is a unique optimal M that results in optimal EE. In the case of independent N and M, there is no optimal(N, M) combination for optimizing EE. The results of numerical simulations are provided, and these results support our analysis. 相似文献