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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,{3.)(Laboratory of Phytochemistry,Kunming institute of Botany,the Chinese Academy of Sciences, Kunming 650204) department of Chemistry Lanzhou University Lanzhou 730000 Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204

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 DITERPENOID ALKALOID FROM DELPHININUM CAERULEUM

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Chinese Chemical Letters 1996年第2期7卷 139-140页

作者： YaN,WANG Yuan Jiang PAN Shao Nong CHEN Yao Zu CHEN(State Key Laboratory of Applied Organic Chemistry and department of Chemistry. lanzhou university, lanzhou 73.000)(Departwent of Chemistry, Zhejiang {3.,Hangzhou 3.0027) State Key Lab. of Appl. Organ. Chem. Department of Chemistry Lanzhou University Lanzhou 730000 China department of Chemistry Zhejiang University Hangzhou 310027 China

A new minor diterpenoid alkaloid containing a C(19)=N-azomethine group, caerunine (1) was isolated from Delphinium caeruleum ***, its structure was determined by spectral data.

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Total Synthesis of (3.,6S)-(+)-3.7-Dimethyl-3.acetoxy-6-hydroxy-octa-1,7-diene

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Chinese Chemical Letters 1999年第2期10卷 111-112页

作者： Zuo Sheng LIU Jiong LAN Yu Lin LI(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,lanzhou university, lanzhou, {3.)Ya Cheng XING Wen CEN(department of Chemistry, Qingdao university, Qingdao, 266071) Natl. Lab. of Appl. Organ. Chemistry Institute of Organic Chemistry Lanzhou University Lanzhou 730000 China department of Chemistry Qingdao University Qingdao 266071 China

A total synthesis of(3., 6S)- (+)-3.7-dimethyl-3.acetoxy-6-hydroxy-octa-1,7-diene via the rearrangement of chiral 2,3.epoxy alcohol, with the system of Ph3., pyridine, I-2 and H2O, is described.

关键词： 2,3.epoxy alcohol rearrangement synthesis

X-Ray Diffraction and NMR Study of Inclusion Complex of Podophyllotoxin with β-Cyclodextrin

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Chinese Chemical Letters 1999年第4期10卷 313-316页

作者： Xue Yi MA Zhi Xin LIAO Yun ZEN Hua Dong XIU Ru LIU and Yao Zu CHEN(department of Chemistry, National Laboratory of Applied Organic Chemistry,lanzhou university,{3.) department of Chemistry Natl. Lab. of Appl. Organ. Chemistry Lanzhou University Lanzhou 730000 China

The inclusion complex of podophyllotoxin (P) with β-cyclodextrin (β-CD) has been studied by X-ray diffractometry and 1HNMR、13.NMR spectroscopy. The complex structure is deduced.

关键词： Podophyllum bexan drum podophyllotoxin β-cyclodextrin inclusion complex X-Ray NMR

Study on the two and three-parameter working stability regions of 3.-TZP suspension

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Science China(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2, ZHANG Xinni3. CHEN Sha’ou3.& QI Ping3.1. department of Chemistry, Qingdao university, Qingdao 266071, China 2. department of Chemistry, Tsinghua university, Beijing 100084, China 3. department of Physics, Qingdao university, Qingdao 266071, China department of Chemistry Qingdao University Qingdao China department of Chemistry Tsinghua University Beijing China department of Physics Qingdao University Qingdao China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3.-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3.-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3.-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3.-TZP, suspension, stability, DLVO theory, interparticle potential energy.

Texual Cohesion and Coherence

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兰州大学学报（社会科学版） 2000年第S1期28卷 250-256页

作者： Zhang Haiying (Foreign Languages Teaching department, Northwest Normal university lanzhou,{3., China)

Cohesion and coherence are two of the most important components in discourse analysis. This thesis investigales some cohesive devices and coherent means. At zhe same time, it gives an account of how a text is identifi... 详细信息

关键词： text cohesion coherence

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, lanzhou{3.) department of Chemistry State Key Lab. of Appl. Organ. Chem. Lanzhou University Lanzhou 730000 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

Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

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Science China Earth Sciences 2010年第9期53卷 1329-1334页

作者： DUAN Yi1, ZHENG ChaoYang2 & WU BaoXiang1 1 Key Laboratory of Petroleum Resources Research, Institute of geology and Geophysics, Chinese Academy of Sciences, lanzhou 73.000, China 2 department of geology, Northwest university, Xi’an 710069, China Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China department of geology Northwest University Xi’an China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in China. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -254‰ to -184‰) are lighter than those in woody plant leaf ( from -195‰ to -142‰ ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13. and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13. values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship

Determination of tectonic background for sedimentary basin from sandstone geochemistry

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Chinese Science Bulletin 1998年第14期43卷 1191-1196页

作者： SHAO Lei 1, K. Stattegger 2 and LI Wenhou 3.1. Laboratory of Marine geology, Tongji university, Shanghai 200092, China 2. Geological and Paleontological Institute, university of Kiel, 24118 Kiel, Germany {3., Northwest Unive Laboratory of Marine geology Tongji University Shanghai China Geological and Paleontological Institute University of Kiel Kiel Germany department of geology Northwest University Xi’an China

The chemical composition of sedimentary rocks is mainly controlled by source rocks. Through examining chemical composition of terrigenous rocks, the tectonic evolution of a sedimentary basin can be modeled. The Turpan Basin belongs to a continental sedimentary basin and its source rocks are derived from the upper continental crust.

关键词： sedimentary rock geochemistry basin analysis Turpan Basin.