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11.
WANG Bo LIU ZhengWei HAN YunKun LEI ZhenXin LUO YangPing & HAN ZhanWen National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming China Key Laboratory for the Structure Evolution of Celestial Objects Graduate University of Chinese Academy of Sciences Beijing 《中国科学:物理学 力学 天文学(英文版)》2010,(3)
Type Ia supernovae (SNe Ia) play an important role in diverse areas of astrophysics, from the chemical evolution of galaxies to observational cosmology. However, the nature of the progenitors of SNe Ia is still unclear. In this paper, according to a detailed binary population synthesis study, we obtained SN Ia birthrates and delay times from different progenitor models, and compared them with observations. We find that the Galactic SN Ia birthrate from the double-degenerate (DD) model is close to those infe... 相似文献
12.
Zhi NA Bei JIANG Hui YANG Zhong Wen LIN Han Dong SUN* Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming Chemistry Deparment of the College of Life Science Chemistry Yunnan University K 《中国化学快报》2001,(8)
Isodon enanderianus (Hand. -Mazz.) H. W. Li, has been used in folk medicine as anti-inflammatory and detoxified agent1. The Isodon genus is known to be rich in ent-kaurane diterpenoids, a series of new ent-kaurane diterpenoids have been isolated from the dried leaves of I. enanderianus2-4. In order to find more biologically active substances, we have carefully investigated the chemical constituents of I. enanderianus collected in Shiping county of Yunnan province, and as a result, enanderi… 相似文献
13.
Hong Ping HE Yue Mao SHEN Xiao Sheng YANG Bin Gui WANG Ling LI Xiao Jiang HAO * Laboratory of Phytochemistry Kunming Institute of Botany the Chinese Academy of Sciences Kunming . The Key Laboratory of Chemistry for Natural Prod 《中国化学快报》2001,(1)
Spiraea japonica L. (Rosaceae) is widely distributed in Yunnan Provence, P. R. China. Previous chemical investigations on S. japonica and its varieties have led to the report of 7 new atisane-type diterpenoids and 38 new diterpene alkaloids of atisine- and hetisine-type1-11. This paper describes the isolation and structure elucidation of two new diterpene alkaloids named spiratines A and B (1-2). Their structures were elucidated on the basis of 1D and 2D NMR experiments (HMQC, HMBC, 1… 相似文献
14.
Hong Ping HE Yun ZOU Yue Mao SHEN Xiao Yan HAO Guo Yin ZUO Xiao Jiang HAO * Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming . Department of Medicinal Chemistry Guiyang Medical College 《中国化学快报》2001,(7)
Micromelum integerrimum (Rutaceae) is a shrub growing in Yunnan Province. Leaves and barks of this plant have been used for the treatment of dysentery, and arthritis1. Previous researches revealed that this plant contained coumarins2-8. Micromelin, the main chemical constituent of this plant, showed significant inhibition against leukaemia P-388 cell line (T/C 149% at 10 mg/kg) but was inactive in lower doses, and also showed significant activity (T/C 228% at 1.25 mg/kg) against Lewis lung… 相似文献
15.
Xue Jing Yanga Ya Ling Yang Wei Zhenb Mou Sheng Liua Jun Hong Chaia a Faculty of Life Science Technology Kunming University of Science Technology Kunming China b Kunming Fruit Business Economics Co.Ltd. Kunming China 《中国化学快报》2009,20(4)
An modified laminar crystal sodium silicate(A1-SKS-6) was synthesized by spray drying and high temperature crystallization using sodium silicate as silicon source,Al atom as inorganic source and hexadecyltrimethy ammonium bromide(CTMAB) as the structure template.The hydrothermal stability of product was at least 1 h.The synthesized material was characterized by XRD and SEM.The results indicated that shape and intensity of XRD diffraction peak at 2θtook changes,but raw materialδphase crystal form kept unc... 相似文献
16.
Three New Diterpenoids from Euphorbia wallichii 总被引:2,自引:0,他引:2
Three new abietane diterpene lactones, 3α-hydroxyjolkinolide A (1), ent-8α, 14β-dihydroxy-13(15)-ene-16(12α)-abietanolide (2) and ent-8α,14α-dihydroxy-13(15)-ene-16(12α)-abietanolide (3) as well as a known abietane diterpene jolkinolide A (4) were isolated from the roots of Euphorbia wallichii. Their structures were elucidated on the basis of spectroscopic analysis. 相似文献
17.
ZHANG Xia LIU Wei XU Yong YANG Liu KONG Wei-song RUI Xiao-dong YANG Shuai CHEN Yong-kuan MIAO Ming-ming .Key Laboratory of Tobacco Chemistry Yunnan Academy of Tobacco Science Kunming P.R.China .Research Development Center of Hongta Tobacco Corporation Limited Yuxi 《高等学校化学研究》2011,(4):550-556
The comparison of solid phase extraction(SPE) for the preconcentration and isolation of polyphenols in tobacco samples was carried out by ultra-high performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) and multivariate analysis.Several adsorbing materials of SPE(C18,NH2,SAX and OASIS) were investigated.It was found that the C18 and OASIS cartridges can not only speed up the purification process,but also simplify the SPE operation.A UPLC/MS/MS was used for the determination of polyphenols ... 相似文献
18.
本文给出了带正则*-断面的正则半群的若干性质,获得了带拟理想正则*-断面的正则半群的一个构造方法.利用这一构造定理,考虑了这类半群上的同余. 相似文献
19.
ZHANG Rong-PingKunming Medical College Kunming Yunnan ChinaSUN Han-DongKunming Institute of Botany Chinese Academy of Sciences Kunming Yunnan China 《中国化学》1997,15(5):425-430
Two new ent-kaurene diterpenoids, angustifolin B and natural hydrogen-bonded 1:1 complex, angustifolin C, as well as four known diterpenoids, angustifolin, isodonal, sodoponin, tri-chorabdal B, were isolated from the leaves of Rabdosia angustifolia. 相似文献
20.
介绍喇曼感生克尔效应光谱(RIKES)的琼斯(Jones)矩阵分析方法.探测光束的传输强度不仅由所经过的每一个光学器件的琼斯矩阵所决定,而且还受到强的泵波在非线性介质样品中感生依赖于强度的二向色性和双折射(克尔效应)对琼斯矩阵的影响.同时计及样品和光学器件由强泵波作用下感生应力和其他外部产生的线双折射对喇曼感生克尔效应光谱观察的不利影响,导出测量系统的功率传输函数的完整表达式和喇曼感生克尔效应光谱的实现观察条件,最后简述以甲笨(C_7H_8)液体为试样的喇曼感生克尔效应光谱实验结果分析. 相似文献