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Simultaneous determination of 14β-lactam antibiotics in cosmetic products by liquid chromatography tandem mass spectrometry method

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Chinese Chemical Letters 2011年第3期22卷 334-337页

作者： Cai Sheng Wu jin Lan Zhang Yan ling Qiao Yi Lin Wang zhi Rong Chen Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China

In this study,a simple and rapid high-performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS） method was established and validated to determine the 14β-lactam antibiotics in cosmetic products,including 1（ceftazidime）,2（cefaclor）, 3（cefdinir）,4（ampicillin）,5（cefalexin）,6（ceftezole）,7（cefotaxim）,8（cefradine）,9（cefuroxime）,10（cephazoline）,11 （cefathiamidine）,12（cefoperazone）,13（cafalotin）,14（piperacillin）.

关键词： High-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) Cosmetic β-Lactam antibiotics

X-ray Flashes from Off-axis Nonuniform Jets

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Chinese Journal of Astronomy and Astrophysics 2004年第5期4卷 473-480页

作者： zhi-Ping jin Da-Ming Wei Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 National Astronomical Observatories Chinese Academy of SciencesBeijing 100012

It has been widely believed that the outflows in gamma-ray bursts are jetted and some jets may have structures like ∈(θ)∝θ-k. We check the possibility that X-ray flashes come from such jets. Both qualitative and quantitative analyses have shown that this model can reproduce most of the observational features of both X-ray flashes and gamma-ray bursts. Using the usual parameters of gamma-ray bursts, we have carried out numerical calculations for both uniform and nonuniform jets, of their fluxes, spectra and peak energies. It seems that nonuniform jets are more appropriate to these observational properties than uniform jets. We have also shown that in our model the observational ratio of gamma-ray bursts to X-ray flashes is about a few units.

关键词： X-rays general-gamma rays bursts-ISM jets and outflows

WEB SERVICES COMPOSING BY MULTIAGENT NEGOTIATION

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Journal of Systems Science & Complexity 2008年第4期21卷 597-608页

作者： Jian TANG Liwei ZHENG zhi jin Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China. Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Institute of Computing Technology Beijing 100190 China.

Composing web services is gained daily attention in Service Oriented Computing. It includes the dynamic discovery, interaction and coordination of agent-based semantic web services. The authors first follow Function Ontology and Automated Mechanism Design for service agents aggregating. Then the problem is formulated but it is ineffective to solve it from the traditional global view. Because the complexity is NP-complete and it is dii^cult or even impossible to get some personal information. This paper provides a multi-agent negotiation idea in which each participant negotiates under the condition of its reservation payoff being satisfied. Numerical experiment is given and well evaluates the negotiation.

关键词： Feasible coalition multi-agent systems negotiation web services composing.

TWO-SCALE FEM FOR ELLIPTIC MIXED BOUNDARY VALUE PROBLEMS WITH SMALL PERIODIC COEFFICIENTS

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Journal of Computational Mathematics 2001年第5期19卷 549-560页

作者： jin-ru Chen Jun-zhi Cui School of Mathematics and Computer Sciences Nanjing Normal UniversityNanjing 210097China ICMSEC Academy of Mathematics and Systems SciencesChinese Academy of SciencesBeijing 100080China

Presents a study which proposed a dual approximate expression of the exact solution for mixed boundary value problems of second order elliptic partial differential equation with small periodic coefficients. Dual appro... 详细信息

关键词： two-scale FEM mixed boundary value small periodic coefficients

A PRIORITY-BASED NEGOTIATIONS APPROACH FOR HANDling INCONSISTENCIES IN MULTI-PERSPECTIVE SOFTWARE REQUIREMENTS

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Journal of Systems Science & Complexity 2008年第4期21卷 574-596页

作者： Kedian MU zhi jin Didar ZOWGHI School of Mathematical Sciences Peking University Beijing 100871 China. Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100190 China. Faculty of Engineering and Information Technology University of Technology Sydney NSW 2007 Australia.

Inconsistency of multi-perspective requirements specifications is a pervasive issue during the requirements process. However, managing inconsistency is not just a pure technical problem. It is always associated with a process of interactions and competitions among corresponding stakeholders. The main contribution of this paper is to present a negotiations approach to handling inconsistencies in multi-perspective software requirements. In particular, the priority of requirements relative to each perspective plays an important role in proceeding negotiation over resolving inconsistencies among different stakeholders. An algorithm of generating negotiation proposals and an approach to evaluating proposals are also presented in this paper, respectively.

关键词： Automated negotiation inconsistency management requirements engineering the priority of requirements viewpoints.

Effect of Molecular Weight of PEG Soft Segments on Photo-stimulated Selfhealing Performance of Coumarin Functionalized Polyurethanes

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Chinese Journal of Polymer Science 2014年第10期32卷 1286-1297页

作者： Jun ling Min-zhi Rong 章明秋 Technology Centre China Tobacco Yunnan Industrial Co. Ltd Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education GD HPPC Lab School of Chemistry and Chemical Engineering Sun Yat-sen University

Polyurethanes consisting of tri-functional homopolymer of hexamethylene diisocyanate （tri-HDI） and polyethylene glycol （PEG） are synthesized, in which photo-reversible coumarin moieties act as pendant groups. Accordingly, the polyurethanes can be repeatedly self-healed under UV lights at room temperature by taking advantages of the photodimerization and photocleavage habits of coumarin. Molecular weight of the soft segment, PEG, is found to be closely related to the healing performance of the polyurethanes. Lower molecular weight PEG that corresponds to higher initial coumarin concentration in the polymer is critical for obtaining higher healing efficiency in the case of the first healing action. Nevertheless, it does not guarantee high reversibility of the photo-remendability during the repeated healing events. In contrast, the polyurethane with moderate molecular weight PEG has achieved balanced performance. Reaction kinetics is less important for the healing effect.

关键词： Polyurethanes Self-healing Coumarin Photochemistry Reversibility.

The new multistage water adsorption model of Longmaxi Formation shale considering the spatial configuration relationship between organic matter and clay minerals

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Petroleum Science 2022年第5期19卷 1950-1963页

作者： zhi-Ye Gao Shu-ling Xiong Lin Wei State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China Unconventional Petroleum Research Institute China University of PetroleumBeijing102249China School of Energy Resources China University of GeosciencesBeijing100083China

The water adsorption by shale significantly affects shale gas content and its seepage ***,the mechanism of water adsorption by shale is still unclear due to its strong heterogeneity and complicated pore *** relationship between the adsorbed water content at different relative humidities(RHs)and shale compositions,as well as shale pore structure and the spatial configuration relationship between organic matter(OM)and clay minerals,was investigated to clarify the controlling factors and mechanisms of water adsorption by Longmaxi Formation shale from the Southern Sichuan Basin in ***,the water adsorption process could be generally divided into three different stages from 0%RH to 99%***,the Johnston’s clay mine ral interlayer pore structure model(JCM),the Freundlich model(FM)and the Dubinin-Astakhov model(DAM)were tested to fit the three water adsorption stages from low RH to high RH,*** fitting results of the JCM and FM at lower RHs were far from good,while the fitting results of DAM at higher RHs were ***,two revised models(LRHM and MRHM)considering the spatial configuration relationship between OM and clay minerals were proposed for the two stages with lower RHs,and performed better fitting results indicating the pronounced effect of the spatial configuration relationship between OM and clay minerals on the water adsorption process of Longmaxi Formation *** outcomes of this study will contribute to clarifying the water distribution characteristics in the pore network of shale samples with variable water contents.

关键词： Longmaxi formation shale Water content OM-clay complexes Spatial occurrence relationship

TWO-SCALE CURVED ELEMENT METHOD FOR ELLIPTIC PROBLEMS WITH SMALL PERIODIC COEFFICIENTS

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Journal of Computational Mathematics 2002年第4期20卷 381-390页

作者： jin-ru Chen Jun-zhi Cui School of Mathematics and Computer Sciences Nanjing Normal UniversityNanjing 210097China LSEC ICMSECAcademy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100080China

This paper is concerned with the second order elliptic problems with small periodic coefficients on a bounded domain with a curved boundary. A two-scale curved element method which couples linear elements and isoparametric elements is proposed. The error estimate is obtained over the given smooth domain. Furthermore an additive Schwarz method is provided for the isoparametric element method.

关键词： two-scale curred element small periodic coefficients

Influence of light intensity and water content of medium on total dendrobine of Dendrobium nobile Lindl

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Asian Pacific Journal of Tropical Medicine 2017年第11期10卷 1095-1100页

作者： jin-ling Li zhi Zhao Hong-Chang Liu Chun-Li Luo Hua-Lei Wang Guizhou University GuiyangGuizhou 550025China Guizhou Key(Engineering)Laboratory for Propagation and Cultivation of Medicinal Plants Guiyang 550025China

Objective: To ascertain the influence of light intensity and water content of medium on the total dendrobine of Dendrobium nobile(D. nobile).Method: The principal component analysis combined with total dendrobine accumulation was conducted to assess the yield and quality of D. nobile in all treatments. In the experiment, D. nobile plants were cultivated in greenhouse as tested materials, and complete test of 9 treatments was adopted with relative light intensities 75.02%, 39.74%,29.93% and relative water content of medium 50%, 65%, 80%. The plants were treated in June and harvested till December. Indexes including agronomic traits, fresh weight and dry weight of stem and leaf, ash content, extract, and dendrobine were ***: Under the light intensity treatments of 75.02% with 50%, 65%, 80% water content of medium, the basal stems of plants were comparatively thicker with more leaves, and the fresh weight and dry weight of stems and leaves were significantly higher than other 6 *** in all treatments contained dendrobine. Under the light intensity treatments of 75.02%with 50%, 65%, 80% water content of medium, dendrobine content of leaves was lower while dendrobine contents of other treatments were more than 0.60%. After comprehensive assessment through the principal component analysis and total dendrobine accumulation, the results showed that 3 treatments with relative light intensity of 75.02% ranked the top ***: In brief, the moderately strong light intensity and water content of medium from low to medium can facilitate the growth and yield of D. nobile plants, while light intensity from moderately weak to weak can enhance the dendrobine content.

关键词： Dendrobium nobile Light intensity Water content of medium Total dendrobine Principal component analysis