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991.
992.
XU Shuwei PAN Qiangyan ZHANG Tianmei YUAN Shuanggui ZHANG Xueqian SHI Shuanghui TIAN Jiaqi HUANG Wenda 《中国物理C(英文版)》1993,17(11):985-987
Activities of 183Os were produced by 39MeV α particles bombarding on a natural tungsten target.β+ spectrum with coincidence gate set on the strongest 382keV γ-rays of 183Os decay was measured.The endpoint energy of the β+ spectrum was determined and the QEC value of 183Os decay was extracted to be 2.24±0.10MeV which is in good agreement with the predicted value 2.30±0.10MeV on the basis of mass systematics. 相似文献
993.
A SYSTEMATIC DISTORTED WAVE IMPULSE APPROXIMATION ANALYSIS OF THE CONVENTIONAL MECHANISM FOR PION DOUBLE CHARGE EXCHANGE 下载免费PDF全文
In the framework of the distorted wave impulse approximation,a systematic analysis is performed for the contribution from the conventional mechanism to the double charge exchange to the double isobaric analog state.The effects of distortions of pions,nuclear wave functions,short-range correlation functions,parameters of form factors,the spin-dependent term in the πN amblitude etc.are examined.It is shown that all these elements are very important and not negligible for the conventional mechanism.But after including the effects of all these elements,the conventional mechanism is still not able to reproduce the experimental excitation function and agular distribution for the energy region of 0—300MeV,therefore the effects of some other mechanisms should be included. 相似文献
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By means of the transformation relation between the ordinary form of boson exponential quadratic operators (BEQO) and its anti-normal product form, we present an effective method to conveniently calculate arbitrary matrix elements of BEQO. By this method, many important matrix elements can be calculated analytically. As a direct application, we obtain the exact solutions of the density matrix and partition function for general boson quadratic Hamiltonian without any information about the energy level. 相似文献
997.
The dithiolenes and diimines and their metal complexes are an important research field in the organic and coordination chemistry[1-3]. Transition metal complexes of a dithiolene and a diimine have excellent electronic functions due to the intramolecular charge transfer from a ligand to other ligand (LL'CT)[3], in which are interested authors[4,5]. Recently we have been studied in detail the synthesis and properties of the title complexes M(mnt)(5-NO2-phen), M=MnⅡ, FeⅡ, CoⅡ, NiⅡ, CuⅡ, ZnⅡ. The structure and properties of the M(mnt)(5-NO2-phen) were characterized by the elemental analysis, TDA-TG, MASS, IR, UV-Vis, fluorescence and EPR spectra,molar conductivity and magnetic susceptibility. In the present abstract we report only the synthesis and spectroscopic characterization of these complexes. 相似文献
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By the aid of the linear quantum transformation (LQT), we derive all of the explicit expressions of Bogoliu bov-Valatin transformation and the rotation transformation in the case of multi-mode Fock space. 相似文献
1000.