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First Total Synthesis of 4,5-Sccoeudesmane-type and Iphionane-type Compounds-Synthesis of 4,5-Dioxo-seco-γ-eudesmol and 5β,11-Dihydroxyiphionan-4-one

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Chinese Chemical Letters 2000年第2期11卷 113-114页

作者： Zhao Ming XIONG Gang ZHOU Xiao Lei GAO Yong Gang CHEN Yu lin LI (National Laboratory of Applied Organic Chemistry and Institute of organic Chemistry, lanzhou university, lanzhou 730000) Natl. Lab. of Appl. Organ. Chemistry Institute of Organic Chemistry Lanzhou University Lanzhou 730000 China

4, 5-Secoeudesmane-type and iphionane-type compounds are sesquiterpenes with new carbon skeletons found in natrual sources in recent years.1-6 The co-occurence of 4, 5-secoeudesmanes, iphionanes and eudesmanes as natrual products suggests that 4, 5-secoeudesmanes, iphionanes most likely are generated biogenetically from eudesmanes, and iphionanes are formed biogenetically by aldol reaction of 4, 5-dioxosecoeudesmanes1,4,6,7. The study on the synthesis of this two kind of new sesquiterpenes has not been reported in the literature.

关键词： type First Total Synthesis of 4,5-Sccoeudesmane-type and Iphionane-type Compounds-Synthesis of 4,5-Dioxo-seco eudesmol and 5 Dihydroxyiphionan-4-one

A Simple and Rapid Method for Synthesis of N,2-Diaryl Diazcnecarboxamides

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Chinese Chemical Letters 1999年第5期10卷 351-352页

作者： Jian Ping LI’ Hong WANG Yu Lu WANG Xiao Yang WANG Cat Lan WANG Dong Lan MA(Department of Chemistry, Henan Normal university, Xinxiang 453002 Department of Chemistry, lanzhou university, lanzhou 730000) Department of Chemistry Henan Normal University Xinxiang 453002 China Department of Chemistry Lanzhou University Lanzhou 730000 China

Using Fe2(SO4)3/H2SO4 as oxidant, nine N,2-diaryl diazcnecarboxamides weresynthesized from diaryl substituted semicarbazides in excellent yield under mild conditions for thefirst time. This method is simple, convenien... 详细信息

关键词： Oxidant synthesis semicarbazides, N,2-diaryl diazenecarboxamides

STUDIES ON PHOTOSENSITIZED OXIDATION OF DITERPENOIDS FROM HEDYCHIUM GENUS

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Chinese Chemical Letters 1996年第1期7卷 25-28页

作者： Qing ZHAO Xiao Jiang Hao / Yao Zu Chen Cheng Zou (Department of Chemistry,lanzhou university, lanzhou 730000)(Laboratory of Phytochemistry,Kunming institute of Botany,the Chinese Academy of Sciences, Kunming 650204) lanzhou UNIV DEPT CHEMLANZHOU 730000PEOPLES R CHINA CHINESE ACAD SCI KUNMING INST BOTLAB PHYTOCHEMKUNMING 650204PEOPLES R CHINA

Several products(2)-(6) were obtained from Hedychenone(1), a furanoid diterpene, by photosensitized oxidation, and the structures were identified by spectral methods. The mechanism of the reaction was discussed.

关键词： SPICATUM

A NEW TEST PROCEDURE FOR NEW BETTER THAN USED IN INCREASING CONVEX ORDERING

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Journal of Systems Science & Complexity 2004年第4期17卷 492-499页

作者： LIXiaohu DepartmentofMathematics LanzhouUniversityLanzhou730000China

A new nonparametric procedure is developed to test the exponentiality against the strict NBUC property of a life distribution. The exact null distribution is derived by the theory of sample spacings, and the asymptotic normality is also established by the large sample theory of L-statistics. Finally, the lower and upper tailed probability of the exact null distribution and some numerical simulation results are presented as well.

关键词： increasing convex ordering L-statistic NBUC sample spacings simulation

A study on the reaction of 2'-hydroxychalcones with I_2-H_2SO_4-DMSO system

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Chinese Journal of Chemistry 1994年第1期12卷 73-78页

作者： ZHANG, Fang-Jie LI, Yu-LinState Key Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry, lanzhou university , lanzhou, Gansu 73000, China State Key Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry Lanzhou University Lanzhou Gansu 73000 China

The reaction of 2'-hydroxychalcones with I_2-H_2SO_4-DMSO system has been studied. The results obtained by us are entirely different from those reported in the literature. The mechanism of this reaction has also been ... 详细信息

关键词： Reaction 2'-hydroxychalcone I_2-H_2SO_4-DMSO system.

Predictions of synthesizing element 119 and 120

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Science China(Physics,Mechanics & Astronomy) 2011年第S1期54卷 61-66页

作者： GAN ZaiGuo1, ZHOU XiaoHong1, HUANG MingHui1, FENG ZhaoQing1 & LI JunQing1,2 1Institute of Modern Physics, Chinese Academy of Sciences, lanzhou 730000, China 2School of Nuclear Science and Technology, lanzhou university, lanzhou 730000, China Chinese Acad Sci Inst Modern Phys Lanzhou 730000 Peoples R China lanzhou Univ Sch Nucl Sci & Technol Lanzhou 730000 Peoples R China

The evaporation residue cross sections of synthesizing superheavy nuclei Z=119, 120 are calculated by different sets of master equations with different dynamical variables. Two methods basically predicted similar results that the Ca induced hot fusion can 48 produce element 119 easier than produce 120, and the evaporation residue cross sections for 119 are detectable by current advanced techniques, while the evaporation residue cross sections are below 0.1 pb for producing element 120.

关键词： super heavy nuclei evaporation residue cross section master equations

A Parallel Computational Scheme on Hybrid Methods

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Journal of Systems Engineering and Electronics 1994年第4期5卷 8-18页

作者： Zhao ShuangsuoDepartment of Mathematics, lanzhou university, lanzhou 730000Wang ChangyinInst. of Mech. & Elec. Eng., Gansu university of Technology, lanzhou 730050 Department of Mathematics Lanzhou University Lanzhou 730000 Inst. of Mech. & Elec. Eng. Gansu University of Technology Lanzhou 730050

Based on the efficient hybrid methods for solving initial value problems of stiff ODEs, this paper derives a parallel scheme that can be used to solve the problems on parallel computers with N processors, and discusses the iteratively B-convergence of the Newton iterative process, finally, the paper provides some numberical results which show that the parallel scheme is highly efficient as N is not too large.

关键词： Hybrid methods Parallel computation Iteratively B-convergence.

An Efficient and Stereoselective Synthesis of (-)-Massoialactone

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Chinese Chemical Letters 1997年第1期8卷 13-14页

作者： Chi ZHANG Fang Ning ZHANG Xue Chao WANG Yu REN and Xin Fu PAN(Department of Chemistry, State Key Laboratory of Applied Organic Chemistry, lanzhou university, lanzhou730000) lanzhou UNIV DEPT CHEMSTATE KEY LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

An efficient and stereoselective four step synthesis of (-)-Massoialactone (1) is described. The key step involves deoxygenation of one alpha,beta - unsaturated carbonyl group in compound 5.

关键词： An Efficient and Stereoselective Synthesis of Cl Zhang Massoialactone

Influence of He-Ne laser irradiation on the excision repair of cyclobutyl pyrimidine dimers in the wheat DNA

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Chinese Science Bulletin 2002年第10期47卷 818-821页

作者： HAN Rong, WANG Xunling & YUE MingSchool of Life Science, Northwest university, Xi’an 710069, China School of Life Science, Shanxi Normal university, Linfen 041004, China School of Life Science, lanzhou university, lanzhou 730000, China School of Life Science Northwest University Xi’an China School of Life Science Shanxi Normal University Linfen China School of Life Science Lanzhou University Lanzhou China

Using agarose gel electrophoresis and T4-endo-deoxyribonuclease-V, which is a kind of restriction endonu-clease of cyclobutyl pyrimidine dimer (CPD), the impacts of He-Ne laser (5mW·mm-2) irradiation on DNA excision repair capacity in damaged wheat cells induced by enhanced ultraviolet-B (10.08kJ·m-2·d-1) radiation were studied. The results indicated that the content of endonuclease sensitive sites (ESS) was reduced by He-Ne laser irradiation, which formed in cells irradiated by enhanced ultraviolet-B. With the irradiation of He-Ne laser, the excision of CPDs and the reduction of single strand breaks (SSB) contents which were the endonuclease sensitive sites (ESS) digested by T4-endodeoxyribonuclease-Y had been stimulated in the wheat cells.

关键词： wheat ultraviolet-B He-Ne laser DNA excision repair.