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991.
S. Shanmuga Sundara Raj Hoong‐Kun Fun Zhong‐Lin Lu Wen Xiao Xiao‐Yang Gong Chang‐Ming Gen 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):1013-1014
The crystal structure of the title compound, C15H14N2O2·H2O, is in the keto tautomeric form and the configuration at the azomethine C=N double bond is E. The molecule is non‐planar, with a dihedral angle of 27.3 (1)° between the aromatic rings. The crystal structure is stabilized by extensive hydrogen bonding involving the water molecule and hydrazone moiety. 相似文献
992.
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
993.
我们利用稀土直接掺杂工艺 ,通过向带隙宽为 4~ 5eV的ⅡA ⅥA族化合物中掺入稀土离子Eu、Sm ,合成了电子俘获材料 (ETM ElectronTrap pingMaterial)CaS :Eu ,Sm。该材料具有红外上转换和光存储特性 ,其红外响应光谱宽 ( 0 .8~ 1 .6μm)、量子转换效率高达 76% [1 ,2 ] 、热稳定性好、使用方便 (室温下工作 ,不需制冷 )、造价低 ,并且具有“常光充能”特性 ,即不需紫外线预激发就能在室温下将红外光 ( 0 .8~ 1 .6μm)直接转换为醒目的可见红光 ,是一种优良的红外探测材料 ,利用该材料制作的… 相似文献
994.
995.
JavaStatSoft, implemented using Java, is an open-source software for performing statistics. The current features of JavaStatSoft
are described. Several well-known patterns the software used are introduced. In addition, based on these patterns and the
experience in developing the software, a new framework, referred to as Data Analysis Module, is proposed to help programmers
develop a user-friendly software for data analysis. 相似文献
996.
997.
The polymerization kinetics of acrylamide (AAM) in water initiated by a ternary enzymatic system of horseradish peroxidase (HRP)/H2O2/acetylacetone (ACAC) was investigated. Conversion–time plots were obtained by dilatometry under different conditions of reaction temperatures and initial concentrations of HRP, ACAC, H2O2, and AAM. The results showed that the effect of the initial concentration of ACAC on the inhibition period was significant. The inhibition period decreases with increasing the initial concentration of ACAC. The inhibition period can be even eliminated by the use of a comparatively large amount of ACAC. From the conversion–time plots, the polymerization rate equation was obtained. Some kinetic features were explained on the basis of analysis of the reaction mechanism. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 475–481, 2012 相似文献
998.
Xie Wen Xiong Caidong Wang Xiangru Wang Zhigang Liu Yuming 《International Journal of Infrared and Millimeter Waves》2008,29(4):406-415
In this paper, a new type of gain guiding fiber is presented, with a parabolic-profile for both the gain and index guiding.
Theoretical investigation shows that the core diameter of such fiber may be up to 200 μm while propagating with single-mode. 相似文献
999.
XiangLin Yang YangJing Wen Ming Xu 《International Journal of Infrared and Millimeter Waves》2000,21(9):1495-1502
The control scheme of long distance optical transmission is treated based on conception of mode-locked Laser cavity in this paper. The general mode-locking equation of fiber ring soliton Laser is first constructed, then we give the general perturbed nonlinear schrödinger equation, and finally the transmission and control equations of optical soliton communication systems with various different configurations, respectively, are obtained. 相似文献
1000.
Zi‐Jing Li Hong‐Xiang Lou Wen‐Tao Yu Pei‐Hong Fan Dong‐Mei Ren Bin Ma Mei Ji 《Helvetica chimica acta》2005,88(10):2637-2640
The known 7,8‐secolabdane type diterpenoids neopallavicinin ( 1 ), pallavicinin ( 2 ), and 18‐hydroxypallavicinin ( 3 ) were isolated from Pallavicinia ambigua, and their structures were determined. The X‐ray crystal structure of 1 was solved, and, in combination with CD and NMR studies, the absolute configurations of 1 – 3 were established. A possible biogenetic pathway for 1 and 2 from a single labdane precursor is proposed. 相似文献