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Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 13.Cs technique

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Chinese science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of Environmental Change and Natural Disaster, the Ministry of Education of china, Beijing Normal university, Beijing 100875, china 2. Institute of Desert Research, Chinese Academy of {3.s, Lanzhou 73.000, china 3. Institute of Mountain Hazards and Environment, Chinese Academy of {3.s, chengdu 610041, china 4. department of Physics, sichuan Union university, chengdu 610041, china Key Laboratory of Environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China Institute of Desert Research Chinese Academy of Sciences Lanzhou China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-13. (13.Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 13.Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 13.Cs reference inventories of 982.11 and 2 3.6.04 Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 13.Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 40 years have been revealed, i.e. the shrub coppicedunes (S1) and semi-fixed dunefields (S3. experienced the alternation of erosion and deposition,while the grasslands (S4, S6 and S7) and dry farmlands (S5) suffered erosion only. By using 13.Csmodel, the average wind erosion rates for shrub coppice

关键词： 13.Cs technique Qinghai-Tibetan Plateau wind erosion.

Statistical properties for the vibrational energy levels of OCS

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Chinese science Bulletin 2002年第8期47卷 641-643页

作者： XIE Daiqian & LU YuhuiInstitute of Theoretical and Computational Chemistry, department of Chemistry, Nanjing university, Nanjing 210093. china department of Chemistry, sichuan university, chengdu 610064, china Institute of Theoretical and Computational Chemistry Department of Chemistry Nanjing University Nanjing China department of Chemistry Sichuan University Chengdu China

A potential energy surface for the electronic ground state of carbonyl sulfide was optimized by using a self-consistent configuration-interaction method and involving the recently observed vibrational band origins up to 8000 cm-1. With the optimized potential, the vibrational energy levels of OCS up to 15000 cm-1 were computed using the discrete variable representation method and Lanczos algorithm. Approximately 480 vibrational energy levels were identified. The statistical investigation showed that the vibrational energy levels of OCS up to 15000 cm-1 are largely regular.

关键词： OCS potential energy surface vibrational spectra sta-tistical property.

Tanshinone prevents cancellous bone loss induced by ovariectomy in rats

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Acta Pharmacologica Sinica 2004年第05期25卷 136-142页

作者： Liao CUI2,3. Tie WU3. Yu-yu LIU3. Yi-feng DENG4, Chun-mei AI4, Huai-qing CHEN22Institue of Biomedical engineering, West china Medical Center, sichuan university, {3. 610041, china 3.5} of Pharmacology, 4Guangdong Key Laboratory for Research and Development of Natural Drugs,Guangdong Medical College, Zhanjiang 524023.china Institue of Biomedical engineering West China Medical Center Sichuan University department of Pharmacology Guangdong Key Laboratory for Research and Development of Natural Drugs Guangdong Medical College

AIM: To investigate the skeletal effects of total tanshinone in ovariectomized rats by analyzing cancellous bonehistomorphometry of fourth lumbar vertebrae (LV4) and proximal tibial metaphyses (PTM). METHODS: Four-month-old Sprague-Dawley female rats were sham-operated and treated with vehicle or ovariectomized and treatedwith either vehicle, total tanshinone (200 mgkg-1d-1, equivalent to 3. gkg-1d-1 of tanshinone II A and 16 mgkg -1d-1 ofcryptotanshinone), or 17a-ethynylestradiol (3. gkg-1d-1 as positive treatment group) starting one day post-sur-gery for 10 weeks. Double in vivo fluorochrome labeling was administered to all rats. The undecalcified longitu-dinal LV4 and PTM sections were cut and stained with Goldners Trichrome (4-m thickness) or unstained (8-mthickness) for the bone histomorphometric analysis. RESULTS: A significant decrease in trabecular bone volume(BV/TV) and trabecular number (Tb.N) and a significant increase in osteoclast surface (OCS/BS) and mineralizingsurface (MS/BS) were found in both LV and PTM of vehicle-treated OVX rats compared with sham *** completely prevented the decreases in BV/TV and Tb.N and the increase in OCS/BS in the LV4, andpartially prevented the decreases in BV/TV and Tb.N in the PTM of OVX rats. In addition, tanshinone increasedtrabecular thickness (***) whereas it did not alter MS/BS. Moreover, tanshinone had no effect on uterine weightand body weight of OVX rats. Estrogen treatment increased BV/TV and Tb.N and decreased OCS/BS, but, alsomarkedly decreased MS/BS and increased uterine weight in OVX rats. CONCLUSION: The current study demon-strated that the adequate supply of tanshinone prevented OVX-induced cancellous bone loss in rats through inhibi-tion of elevated bone resorption.

关键词： tanshinone cryptotanshinone 2-fluoro-17alpha-ethynylestradiol ovariectomy bone and bones osteoclasts osteoporosis histocytochemistry morphology

New-generation biomedical materials:Peptide dendrimers and their application in biomedicine

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science china Chemistry 2010年第3期53卷 458-478页

作者： GU ZhongWei,LUO Kui,SHE WenChuan,WU Yao & HE Bin National engineering Research Center for Biomaterials,sichuan university,{3. 610064,china National engineering Research Center for Biomaterials Sichuan University Chengdu China

Peptide dendrimers are attractive synthetic polymers and have been widely used as a new generation of biomaterials in recent *** dendrimers,as well as general dendrimers,may be synthesized to reach nano sizes,and display well-defined architectures,highly-branched structures,high density of functional terminal groups,and controllable molecular *** the other hand,peptide dendrimers have properties similar to proteins and some special characteristics,such as good biocompatibility,water solubility and resistance to proteolytic *** to these advantages,peptide dendrimers have received considerable attention in *** review focuses on the development of peptide dendrimers with emphasis on their applications both in diagnostics and in therapy.

关键词： peptide dendrimers molecular probes drug delivery gene delivery

Theoretical study on the hydrolysis mechanism of N,N-dimethyl-N′-(2′,3.-dideoxy-3.-thiacytidine)formamidine

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science china Chemistry 2008年第10期51卷 911-917页

作者： ZHANG Chang1 & XUE Ying2? 1 College of Chemistry and Environment Protection engineering, Southwest university for Nationalities, chengdu 610041,{3. 2 College of Chemistry, sichuan university, chengdu 610064,{3. College of Chemistry and Environment Protection engineering Southwest University for Nationalities Chengdu China College of Chemistry Sichuan University Chengdu China

The hydrolysis mechanisms of N,N-dimethyl-N′-(2′,3.-dideoxy-3.-thiacytidine)formamidine (FA-3.C) in the gas phase and in aqueous solution were studied by use of the density functional theory B3.YP/6-3.+G(d, p) method. Two possible reaction pathways in the title reaction were considered. In one pathway water attacks the C=N double bond first (path A) while in the other water attacks the C—N single bond first (path B). The calculated results indicate that the first step in both pathways is the rate-limiting process and path A is more favorable than path B in the gas phase. The effect of solvent water on the title reaction was assessed at the B3.YP/6-3.+G(d, p) level of theory based on the po-larizable continuum model (CPCM). In water the first mechanism (path A) is also favored.

关键词： N N-dimethyl-N′-(2′ 3.-dideoxy-3.-thiacytidine)formamidine hydrolysis solvent effect B3.YP polarizable continuum model

Incipient Motion of Bed Load Sediment and Its Application in the Three Gorges Hydro Project

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四川大学学报（工程科学版） 2005年第S1期37卷 102-105页

作者： HE Wenshe~(1,3. CAO Shuyou~2 YUAN Jie~3.DAI Huichao~3.(1.Lanzhou Jiao Tong Univ.,Lanzhou 73.070,china 2.State Key Lab.of Hydraulics and Mountain River Eng.,sichuan Univ.,chengdu {3.,china 3.china Yangtze Three Gorges Project Development Corporation,Hubei Yichang 443.02,china) Lanzhou Jiaotong Univ. Lanzhou 730070 China china Yangtze Three Gorges Project Development Corporation Yichang 443002 China State Key Lab. of Hydraulics and Mountain River Eng. Sichuan Univ. Chengdu 610065 China

A formula for the calculation of critical shear stress of non-uniform sediment was developed by on river bed has been established while considering the relative degree expose of *** values of the Coeffi- cients in the formula have been *** formula has been verified with prototype observation data, flumes data of both nature and lightweight *** computed results fully reflect the characteristics of thresh- old motion of non-uniform *** result have been used in some physical mo...

关键词： non-uniform sediment incipient motion bed load Three Gorges Hydro Project

Bioinformatics Data Distribution and Integration via Web Services and XML

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Genomics, Proteomics & Bioinformatics 2003年第4期1卷 299-303页

作者： Xiao Li and Yizheng ZhangCollege of Life science, sichuan university/sichuan Key Laboratory of Molecular Biology and Biotechnology,{3. 610064, china. College of Life science Sichuan University/Sichuan Key Laboratory of Molecular Biology and Biotechnology Chengdu 610064 China.

It is widely recognized that exchange, distribution, and integration of biological data are the keys to improve bioinformatics and genome biology in post-genomic era. However, the problem of exchanging and integrating biological data is not solved satisfactorily. The extensible Markup Language (XML) is rapidly spreading as an emerging standard for structuring documents to exchange and integrate data on the World Wide Web (WWW). Web service is the next generation of WWW and is founded upon the open standards of W3. (World Wide Web Consortium) and IETF (Internet engineering Task Force). This paper presents XML and Web Services technologies and their use for an appropriate solution to the problem of bioinformatics data exchange and integration .

关键词： biological data integration extensible Markup Language (XML) web services extensible Stylesheet Language (XSL)

On the Birch-Swinnerton-Dyer Conjecture of Elliptic Curves E_D:y^2=x^3.D^2x

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Acta Mathematica Sinica,English Series 2000年第2期16卷 229-236页

作者： Delang Li department of Mathematics,sichuan Union university,{3. 610064,P.R.china Ye Tian department of Mathematics,Columbia university,New York,NY 10027,USA department of Mathematics Sichuan Union University Chengdu 610064 P. R. China department of Mathematics Columbia University New York NY 10027 USA

We prove in this paper that the BSD conjecture holds for a certain kind of elliptic curves.

关键词： Elliptic curve BSD conjecture Graph 2-component

Solvent Extraction of Some Lanthanides with Trioctylphosphine Oxide in Molten Paraffin Wax

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Rare Metals 2001年第1期20卷 18-23页

作者： Bi Wang, Xiaojun Guo, Haiyan Fan, Bo Peng, Jinzhang Gao (department of Chemistry, Northwest Normal university, Lanzhou 73.070, china Dept. of Leather {3., sichuan university, Chendu 610065, china.) 四川大学四川成都 610065 西北师范大学甘肃兰州 730070

The extraction behavior of Ln(III) (Ln=Nd, Sm, Tb and Yb) with trioctylphosphine oxide (TOPO) in molten paraffin wax has been studied. The effect of pH, TOPO concentration, medium, stirring time and the amount of sails added on the distribution of lanthanides between two phases were investigated. Two different compositions Ln(H2O)(t-2) (TOPO)(2)(OH)(2)NO3.(Ln=Nd and Sm) and Ln(H2O)(s-1) (TOPO)(2)(OH)(NO3.(2) (Ln=Tb and Yb) were determined by slope analysis method. The equilibrium extraction constant K-ex and pH(1/2) value were calculated and the thermodynamic parameters were obtained from the dependence of K-ex on the temperature.

关键词： lanthanides trioctylphosphine oxide extraction molten paraffin