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Regioselective aminohalogenation of β-nitrostyrenes using NCS and NBS as nitrogen/halogen sources

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science china Chemistry 2010年第1期53卷 140-146页

作者： ZHI SanJun1,2,SUN Hao2,LIN Chen2,ZHANG GuangQian2,LI GuiGen4 & PAN Yi2,3.1 department of Chemistry,Huaiyin Normal university,Huai’an 221003.china 2 School of Chemistry and Chemical Engineering,{3. university,{3. 210093,china 3.State Key Lab of Coordination Chemistry,{3. university,{3. 210093,china 4 department of Chemistry and Biochemistry,Texas Tech university,Lubbock,Texas 79409-1061,USA 1. department of Chemistry Huaiyin Normal University Huai’an 221003 China2. School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China4. Department of Chemistry and Biochemistry Texas Tech University Lubbock Texas 79409-1061 USA3. State Key Lab of Coordination Chemistry Nanjing University Nanjing 210093 China

Aminohalogenation reaction of β-nitrostyrenes with N-halosuccinimides(N-chloro and N-bromosuccinimides) has been successfully conducted by using nickel acetate as a catalyst in the presence of potassium carbonate and succinimide as *** reaction was easily performed at room temperature under nitrogen gas protection to give dihalorinaed haloamino products in good to excellent yields(60%-98%).The structure has been confirmed by X-ray crystal structure analysis.

关键词： aminohalogenation vicinal haloamines β-nitrostyrenes NBS NCS

Technical framework for Internetware: An architecture centric approach

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science in china(Series F) 2008年第6期51卷 610-622页

作者： YANG FuQing1,2, Lü Jian3.4 & MEI Hong1,2 1 Key Laboratory of High Confidence Software Technologies (Peking university), Ministry of Education, Beijing 100871, china 2 School of Electronics Engineering and Computer science, Peking university, Beijing 100871, china 3.State Key Laboratory for Novel Software Technology, nanjing 210093, china 4 department of Computer science and Technology, nanjing university, nanjing 210093, china 1. Key Laboratory of High Confidence Software Technologies (Peking university) Ministry of Education Beijing 100871 China 2. School of Electronics Engineering and Computer science Peking University Beijing 100871 China 3. State Key Laboratory for Novel Software Technology Nanjing 210093 China 4. department of Computer science and Technology Nanjing University Nanjing 210093 China

Being a new software paradigm evolved by the Internet, Internetware brings many challenges to the traditional software methods and techniques. Sponsored by the national basic research program （973., researchers in china have developed an architecture centric technical framework for the definition, incarnation and engineering of Internetware. First of all, a software model for Internetware is defined for what to be, including that Internetware entities should be packaged as components, behaving as agents, interoperating as services, collaborating in a structured and on demand manner, etc. Secondly, a middleware for Internetware is designed and implemented for how to be, including that Internetware entities are incarnated by runtime containers, structured collaborations are enabled by runtime software architecture, Internetware can be managed in a reflective and autonomic manner, etc. Thirdly, an engineering methodology for Internetware is proposed for how to do, including the way to develop Internetware entities and their collaborations by transforming and refining a set of software architectures which cover all the phases of software lifecycle, the way to identify and organize the disordered software assets by domain modeling, etc.

关键词： Internetware component software architecture agent middleware

A model for the optical flares from the Galactic transient SWIFT J195509+261406

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science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 91-93页

作者： XU Ming & HUANG YongFeng department of Astronomy,nanjing university,nanjing 210093,china 1. department of Astronomy Nanjing University Nanjing 210093 China

The Galactic hard X-ray transient SWIFT J195509+261406 was first observed as gamma-ray burst GRB *** 3.days after the burst,more than forty optical flares had been ***,we propose that this peculiar event should be associated with a white *** hard X-ray burst itself may be triggered by a collision between two planets orbiting the white *** cracked fragments produced in the collision then fell onto the surface of the white dwarf over several days,giving birth to the observed optical flares via cyclotron *** model can satisfactorily explain the basic features of the observations.

关键词： gamma-ray bursts white dwarfs cyclotron radiation

On the Conditions of a Center and General Integrals of Quadratic Differential Systems

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Acta Mathematica Sinica,English Series 2001年第2期17卷 229-236页

作者： Wei Yin YE department of Mathematics. nanjing Normal university. nanjing 210097, P. R. china Yan Qian YE department of Mathematics. nanjing university, nanjing 210093, P. R. china department of Mathematics Nanjing Normal University Nanjing 210097 P. R. China department of Mathematics Nanjing University Nanjing 210093 P. R. China

We give the general integral of quadratic differential system with center in two cases under the Chinese classification.

关键词： Quadratic differential system Center General integral

The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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science china earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3. ZHANG Jie2, SONG Linhua1 & BAO Haosheng2 1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china 2. {3. of Geography, nanjing university, nanjing 210093, china 3. School of earth sciences and Resources, china university of Geosciences, Beijing 100083. china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China department of Geography Nanjing University Nanjing 210093 China School of earth sciences and Resources China University of Geosciences Beijing 100083 China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (3.) and minor-scale (10-3.10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

Responses of soil nutrient to driving mechanism in Taihu Lake basin in last 20 years

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Journal of Geographical sciences 2001年第1期11卷 92-98页

作者： CHEN Fu, PENG Bu-zhuo, BAO Hao-sheng (department of Urban and Resources science, nanjing university,{3., china) department of Urban and Resources science Nanjing University Nanjing China

The objectives of this study is to understand the changing law of soil nutrient quality in Taihu Lake basin, Yangtze Delta in last 20 years, and reveal the relationship between soil nutrient changes and human driving forces in regional level over long period of time. Experiment on long-term collecting samples was conducted to study changes of soil organic matter, total N, available N, available P and available K in Dongting town, Wuxi city during the last 20 years. The paper analyses the co-relationship of the fluctuation of soil nutrient and state policy, cultivating practice, agricultural input, and per hectare agricultural net income. The results showed that at first the content of soil organic matter increased, then decreased, and increased again. The content of total N and available N steadily increased. The content of available K and available P steadily decreased. The authors found that the influence of state policy and cultivating practice on soil nutrient quality index (SNQI) is obvious, agricultural input and SNQI are positively correlated, and per hectare agricultural net income and SNQI are negatively correlated.

关键词： soil nutrient SNQI human driving mechanism Taihu Lake basin

The early high-energy afterglow emission from short GRBs

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science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 157-160页

作者： HE HaoNing & WANG XiangYu department of Astronomy,nanjing university,nanjing 210093,china nanjing Univ Dept Astron Nanjing 210093 Peoples R China

We calculate the high energy afterglow emission from short Gamma-Ray Bursts(SGRBs) in the external shock *** are two possible components contributing to the high energy afterglow:electron synchrotron emission and synchrotron self-Compton(SSC) *** find that for typical parameter values of SGRBs,the early high-energy afterglow emission in 10 MeV-10 GeV is dominated by synchrotron *** a burst occurring at redshift z = 0.1,the high-energy emission can be detectable by Fermi LAT if the blast wave has energy E ≥ 1051 ergs and the fraction of electron energy εe≥ *** provides a possible explanation for the high energy tail of SGRB 081024B.

关键词： gamma-ray burst radiation mechanism blast wave

Advances in research of sulphide ore textures and their implications for ore genesis

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Progress in Natural science:Materials International 2006年第10期16卷 1007-1021页

作者： GU Lianxing, ZHENG Yuanchuan, TANG Xiaoqian, WU Changzhi and HU Wenxuan (State Key Laboratory for Endogenic Metal Deposits Research, department of earth sciences,{3., nanjing 210093, china) [a]State Key Laboratory for Endogenic Metal Deposits Research Department of Earth Sciences Nanjing University Nanjing China

Important advances in research of sulphide ore textures in recent years have deepened our understanding of ore genesis of related mineral deposits. Pressure solution of sulphide minerals has been suggested as a mechanism for remobilization of ore materials, whereas pressure solution of the gangues is believed to raise the grade of the primary ores. We have known that precipitation of base metal sulphides from fluids prefers crystal and crack surfaces of pyrite to form overgrowth. Therefore, pyrite-bearing embryo beds in a sedimentary sequence can be acted as effective crystal seed beds and are favorable for fluid overprinting to form huge statabound deposits. Texture studies of various sulphides can be used to interpret the entire history of sedimentation, diagenesis, deformation and metamorphism of the ores. The study of chalcopyrite disease in sphalerite has brought about the idea of zone refining, and given a new explanation to metal zonation in massive sulphide deposits. Ductile shearing of sulphide ores may form ore mylonites, which will become oreshoots enriched in Cu, Au and Ag during late-stage fluid overprinting. Despite that various modern analytical techniques are being rapidly developed, ore microscopy remains to be an unreplaceable tool for ore geologists. Combined with these modern techniques, this tool will help accelerate the development of theories on ore genesis.

关键词： pyrite pyrrhotite chalcopyrite pressure sulution overgrowth mylonite.

An MSX infrared analysis of the superbubble around the giant HII region NGC3.03

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science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 271-273页

作者： WANG Jia & CHEN Yang department of Astronomy,nanjing university,nanjing 210093,china 1. department of Astronomy Nanjing University Nanjing 210093 China

Using the MSX mid-infrared observations,we reveal a 100pc-scale superbubble surrounding the giant HII region *** suggest that the diffuse surrounding infrared emission in bands A,C,and D is dominated by that of PAH and the emission in band E is dominated by that of dust *** fitted dust temperature is consistent with heating by the central cluster's UV *** derived gas-to-dust mass ratio for the bubble shell is of order 102.

关键词： superbubble HII region cluster PAH dust