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Sequence Analysis of Polypeptide by Mass Spectrometry

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Chemical Research in Chinese Universities 1993年第4期9卷 288-295页

作者： YANG Hou-jun , LI Xiao-ling, HU Xiao-yu and CHEN Yao-zu (State Key Laboratory of Applied Organic Chemistry, lanzhou university, lanzhou, 730000)

The method described in this work provides a sensitive and fast technique for investigating the primary structure of peptides with molecular weight up to 3340 amu. Usually, the metastable ion kinetic energy spectra (MIKES) and collisional activated decomposition (CAD) spectra provide complementary information for the FAB mass spectra, the MIKES and CAD spectra generally contain high-mass sequence ions.

关键词： Peptide Sequence analysis Mass spectrometry.

Total Synthesis of Several 8, 8",-Biflavones

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Chinese Chemical Letters 1998年第4期9卷 351-352页

作者： Lian Yun ZHAO Shi Jun DA Yu Lin LI Wen CEN Ya Cheng XING(National Laboratory of Applied Organic Chemistry, lanzhou university, lanzhou 730000 Department of Chemistry, Qingdao university, Qingdao 266071) lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China Ocean Univ Qingdao Dept Chem Qingdao 266071 Peoples R China

Four 8, 8'-biflavones were synthesized by the iodination of 2'-hydroxychalcones at 8-position in I-2-H2SO4-DMSO system as the key step followed by coupling under Ullmann reaction conditions.

关键词： 8,8 ''-biflavones synthesis I-2-H2SO4-DMSO system coupling Ullmann reaction

Total Synthesis of (-)-Baimuxifuranic Acid

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Chinese Chemical Letters 1997年第8期8卷 697-700页

作者： Yong Gang CHEN Zhao Ming XIONG Jiong YANG Yu Lin LI(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry lanzhou university,lanzhou 730000) lanzhou UNIV NATL LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA lanzhou UNIV INST ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

The first total synthesis of (-)-baimuxifuranic acid (1) starting from (-)-carvone has been described. In our studies a surprising allylic oxidation was found in the oxidation of alpha beta-unsaturated aldehyde 5 with... 详细信息

关键词： ppm MHz EIMS Baimuxifuranic Acid Total Synthesis of

Tandem Lewis acid catalyzed coupling/semipinacol rearrangement of allylic alcohol

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Science China Chemistry 2010年第1期53卷 147-150页

作者： YUAN DaoYi,ZHANG YongQiang,TU YongQiang,CHEN ZhiHua & ZHAO Xiong State Key Laboratory of Applied Organic Chemistry Department of Chemistry,lanzhou university,lanzhou 730000,China 1. State Key Laboratory of Applied Organic Chemistry Department of Chemistry Lanzhou University Lanzhou 730000 China

Construction of the polyaryl quaternary unit through a ZnBr2 catalyzed tandem coupling/semipinacol rearrangement participated by allylic cations was reported for the first time.

关键词： coupling semipinacol rearrangement allylic cation quaternary center

A piecewise-integration method for simulating the influence of external forcing on climate

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Progress in Natural Science:Materials International 2008年第10期18卷 1239-1247页

作者： Zhifu Zhang Chongjian Qiu Chenghai Wang Key Laboratory of Arid Climatic Changing and Reducing Disaster of Gansu Province,College of Atmospheric Sciences,lanzhou university.lanzhou 730000.China Key Laboratory of Arid Climatic Changing and Reducing Disaster of Gansu Province College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China

Climate drift occurs in most general circulation models (GCMs) as a result of incomplete physical and numerical representation of the complex climate system,which may cause large uncertainty in sensitivity experiments evaluating climate response to changes in external *** solve this problem,we propose a piecewise-integration method to reduce the systematic error in climate sensitivity studies. The observations are firstly assimilated into a numerical model by using the dynamic relaxation technique to relax to the current state of atmosphere,and then the assimilated fields are continuously used to reinitialize the simulation to reduce the error of climate simulation. When the numerical model is integrated with changed external forcing,the results can be split into two parts,background and pertur- bation fields,and the background is the state before the external forcing is *** piecewise-integration method is used to con- tinuously reinitialize the model with the assimilated field,instead of the ***,the simulation error of the model with the external forcing can be *** this way,the accuracy of climate sensitivity experiments is greatly *** with a simple low-order spectral model show that this approach can significantly reduce the uncertainty of climate sensitivity experiments.

关键词： Climate model External forcing Sensitivity experiment Low-order spectral model Dynamic relaxation technique

Regioselective Synthesis of Two Novel 4-alkenyloxy-2,6-dihydroxyacetophenones

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Chinese Chemical Letters 1998年第9期9卷 799-800页

作者： Chu Sheng HUANG Zhe ZHANG Shu Hua LI Yu Lin LI (National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry, lanzhou university, lanzhou 730000) lanzhou Univ Inst Organ Chem Lanzhou 730000 Peoples R China lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China

Two novel Acetophenones, 4-(1'-geranyloxy)-2,6-dihydroxyacetophenone 1 and 4-(1'-farnesyl)-2,6-dihydroxyacetophenone 2 isolated from the fruit of Evodia merrillii and from the aerial parts of Borronia ramosa respectiv... 详细信息

关键词： 4-alkenyl-2 6-dihydroxyacetophenones total synthesis

A Study on the Driving Force for Binding of Benzene Derivatives by α-and β-Cyclodextrin

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Chinese Chemical Letters 1998年第5期9卷 463-464页

作者： Shuang Hui LUO Hui Ming JMNG You Cheng LIU(National Laboratory of Applied organic Chemistry, lanzhou university, lanzhou 730000)Qing Xiang GUO (Department of Chemistry, university of Science and Technology of China, Hefei 230026) lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China Univ Sci & Technol China Dept Chem Hefei 230026 Peoples R China

A three-dimensional diagram shows that the association constants (Ka) for the inclusionof a- and 6-CD with substitUted benzene are mainly correIated with the molar refraction (R.) andhydrophobic constant (%) of the substitUents of guest compounds. It reveals that the inclusion ofcyclodextrin with the substitUted benzene is dondnantly driYen by van der Waals forces andhydrophobic interactions.

关键词： benzene derivatives cyclodextrin driving force inclusion complexation

SYNTHESIS OF 3,7-DINITRODIBENZOBROMONIUN SALTS

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Chinese Chemical Letters 1990年第1期1卷 69-70页

作者： Zi Jie HOU Institute of Organic Chemistry,lanzhou university,lanzhou 730000

3,7-Dinitrodibenzobromonium salts were prepared directly by reaction of 4,4'-dinitrobiphenyl with both sodium bromide and potassium persulphate in concentrated sulphuric acid.

关键词： ppm SYNTHESIS OF 3,7-DINITRODIBENZOBROMONIUN SALTS

Effect of cooling rate on plastic deformation of Zr-based bulk metallic glasses

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Progress in Natural Science:Materials International 2012年第1期22卷 21-25页

作者： Chunyan Li a,Shengzhong Kou a,b,Yanchun Zhao a,Guangqiao Liu b,Yutian Ding a a State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials,lanzhou university of Technology,lanzhou 730050,China b Key Laboratory of Non-ferrous Metal Alloys and Processing of the Ministry of Education,lanzhou university of Technology,lanzhou 730050,China [a] State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials Lanzhou University of Technology Lanzhou 730050 China [b] Key Laboratory of Non-ferrous Metal Alloys and Processing of the Ministry of Education Lanzhou University of Technology Lanzhou 730050 China

The effect of cooling rate on plastic deformation of Zr-based bulk metallic glasses has been *** specimens with the diameters of 3 mm,4 mm and 6 mm cut from the same ladder-shaped Zr 55 Al 10 Ni 5 Cu 30 BMG rod were used in the present *** experimental results indicated that the different plastic strains were induced for the three type compression *** compressive plastic strain increased with the decreasing diameter for the as-cast specimens,which means that the compressive plastic strain increased with the increasing cooling *** reason of the difference is attributed to the free volume existed in the BMGs during the rapid solidification,and the larger free volume was contained in the specimen fabricated with the higher cooling *** has been found that the prominent serrations and multiple shear bands appeared during the compressive deformation tests of the specimen with smaller diameter of 3 mm,indicating that the specimen with smaller diameter exhibits better plasticity due to more free volume content.

关键词： Bulk metallic glasses Cooling rate Serration Plastic deformation Free volume