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221.
In the framework of the relativistic mean field theory, the effects of the δ meson on the direct Urca (DURCA) processes are investigated. In a neutron star, the DURCA processes involving nucleons, Λ and Ξ- can take place while the process involving the Ξ0 can not. With the inclusion of the δ meson, the threshold densities for the DURCA processes become lower. With the δ included, the threshold neutron star mass for the DURCA process among nucleons and electrons becomes smaller while the threshold masses for the processes involving hyperons become larger. When the δ meson is included, the total neutrino emissivity remarkably increases in the density range of 0.32--0.41 fm-3. The total neutrino luminosity increases with the neutron star mass first and then decreases. The neutrino luminosity gets larger with the inclusion of the δ meson. The cooling of the EXO0748-676 is sensitive to the isovector scalar interaction. 相似文献
222.
This paper constructs a class of Harish-Chandra modules with multiplicity ≤1 of the two parameter deformation of Virasoro algebra and proves a classification theorem. 相似文献
223.
Xiao Bin YIN Rui WANG Xiao Long LI College of Mathematics Computer Science Anhui Normal University Anhui P.R.China 《数学研究与评论》2011,(6)
In this paper,we introduce a non-trivial generalization of ZI-rings-quasi ZI-rings.A ring R is called a quasi ZI-ring,if for any non-zero elements a,b ∈ R,ab = 0 implies that there exists a positive integer n such that an = 0 and anRbn = 0.The non-singularity and regularity of quasi ZI,GP-Vˊ-rings are studied.Some new characterizations of strong regular rings are obtained.These effectively extend some known results. 相似文献
224.
A self-intermolecular cyclocondensation reaction of 3,4-dihydropyrimidine-2-thione(DHPM) to give a novel tricyclic structure containing DHPM core in the presence of diethyl azodicarboxylate(DEAD) and triphenylphosphine(TPP) at room temperature is reported. 相似文献
225.
Zhi-zhuang Joe 《高等学校化学研究》2011,(3):474-477
PTPRU is an MAM domain-containing receptor-like protein tyrosine phosphatase. Previous studies have demonstrated an important role of the enzyme in the maintenance of epithelial integrity and in the regulation of the Wnt/β-catenin signaling pathway. To better understand the function of PTPRU, we cloned and expressed the intracellular portion of PTPRU as a GST fusion protein in E. coli cells. We purified the protein to homogeneity and used it to immunize mice for antibody production. The resultant antibody s... 相似文献
226.
The analytical expression for the complex amplitude of light reflected from a wedge-shaped thin film is derived. For plane wave incidence, a simple ray tracing approach is used to calculate Goos-H(a|¨)nchen (GH) shifts; and for non-plane wave incidence, for example, a Gaussian beam, the angular spectrum approach of plane wave is used in simulation. The two approaches predict that a wedge-shaped thin film can produce large negative longitudinal GH shifts. Although the reflectivity is small near the condition... 相似文献
227.
Ming Xia LI Yan Ming WANG Ru Ru CHEN* Research Institute of Elemento-Organic Chemistry Nankai University Tianjin Pittsburgh University Medical Center Pittsburgh PA U. S. A 《中国化学快报》2001,(6)
The chiral diols ((,(,((,((-Tetraaryl-1,3-dioxolane-4,5-dimethanols) have been used for the formation of cyclic titanates and similar derivatives of Mg, Al and Zr. These complexes of oxophilic metal centers were employed in catalytic and stiochiometric enantioselective reactions such as enantioselective addition reactions of carbon-centered nucleophiles to aldehydes1, [2+2] cycloadditions2, and Diels-Alder reactions3. So far, the two hydrogen atoms of all this type of diols are in trans form… 相似文献
228.
ZHAO Hai-feng WU Lei LU Ming HU Yu-lin HAN Xiao LI Zheng-qiang . Key Laboratory for Molecular Enzymology & Engineering Ministry of Education Jilin University Changchun P. R. China . Medical 《高等学校化学研究》2011,(3):450-454
Lipid-bound [VHb(406)] and lipid-free [VHb(402)] wide type Vitreoscilla hemoglobin were separated from E. coli BL21(DE3). The RZ is 3.30 for [VHb(406)] and 3.15 for [VHb(402)], respectively. VHb(406) shows a characteristic absorption band at 626 nm, while VHb(402) shows one at 644 nm, and it has more α-helix than VHb(402). Data of Raman spectra experiment shows under the excitation wavelength 488 nm, υ4 vibration of both VHb(402) and VHb(406) had a pure and strong signal at 1375 cm-1, which proves that iron... 相似文献
229.
研究了桂枝和桂皮醛对环丙沙星在小鼠体内分布的影响,并基于此探讨了桂枝作为引药使用的作用机制.实验中将小鼠分为三组,分别灌胃生理盐水、桂枝(50gkg-1)和桂皮醛(0.25mLkg-1),然后对三组小鼠尾静脉注射环丙沙星(20mgkg-1),并以荧光法测定不同时间点小鼠体内各组织中环丙沙星的浓度.结果显示桂枝、桂皮醛均促进了环丙沙星在四肢的分布,桂枝与桂皮醛组相对于生理盐水组可将环丙沙星在四肢的含量提高约40%~200%,证实了桂枝引药到达肢节的作用.桂枝与桂皮醛组对环丙沙星分布情况的影响没有显著性差异,说明桂皮醛很可能是发挥桂枝引药作用的主要物质. 相似文献
230.
ZHAO Xiao-ping JIN Ye-cheng ZENG Xing ZHANG Bo-li ZHANG Yu-feng .Tianjin State Key Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese Medicine Tianjin P.R.China .College of Preclinical Medicine Zhejiang Chinese Medical University Hangzhou .College of Pharmaceutical Sciences Zhejiang University Hangzhou 《高等学校化学研究》2011,(4):562-565
In order to identify the potential nephrotoxic compounds in traditional Chinese medicine Lithospermum erythrorhizon,it was separated into serial fractions according to their polarities.An in vitro method was utilized to determine the nephrotoxicity of these fractions with the help of fluorescence image analysis.As a result,the primary fraction A05 and its secondary fractions C06 C09 and C12 C14 were found to have significant toxicity to LLC-PK1 cell line,as determined by the survive rate less than 20% after... 相似文献