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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, nanjing university,{3.) [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

A relative local variational principle for topological pressure

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science china Mathematics 2010年第6期53卷 1491-1506页

作者： MA XianFeng1,CHEN ErCai2,3.& ZHANG AiHua2,4 1department of Mathematics,East china university of science and Technology,shanghai 20023.,china 2school of Mathematics and Computer science,nanjing Normal university,nanjing 210097,china 3.enter of Nonlinear science,nanjing university,nanjing 210093.china 4College of Mathematics and Physics,nanjing university of Posts and Telecommunications,nanjing 210046,china 1. department of Mathematics East China University of Science and Technology Shanghai 200237 China2. School of Mathematics and Computer Science Nanjing Normal University Nanjing 210097 China3. Center of Nonlinear Science Nanjing University Nanjing 210093 China4. College of Mathematics and Physics Nanjing University of Posts and Telecommunications Nanjing 210046 China

We define the relative local topological pressure for any given factor map and open cover,and prove the relative local variational principle of this *** precisely,for a given factor map π:(X,T)→(Y,s) between two topological dynamical systems,an open cover U of X,a continuous,real-valued function f on X and an s-invariant measure ν on Y,we show that the corresponding relative local pressure P(T,f,U,y) satisfies sup μ∈M(X,T){ hμ(T,U|Y)+∫X f(x)dμ(x) :πμ=ν}=∫Y P(T,f,U,y)dν(y),where M(X,T) denotes the family of all T-invariant measures on ***,the supremum can be attained by a T-invariant measure.

关键词： pressure conditional entropy relative local variational principle

The inversion of the real kinematic properties of coronal mass ejections by forward modeling

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Research in Astronomy and Astrophysics 2011年第2期11卷 237-244页

作者： You Wu 1 and Peng-Fei Chen 1,2 1 department of Astronomy,nanjing university,nanjing 210093.china 2 Key Lab of Modern Astron.and Astrophys.,Ministry of Education,nanjing 210093.china department of Astronomy Nanjing University Nanjing 210093 China Key Lab of Modern Astron. and Astrophys. Ministry of Education Nanjing 210093 China

Kinematic properties of coronal mass ejections （CMEs） suffer from projection effects,and it is expected that the real velocity should be larger and the real angular width should be smaller than the apparent *** attempts have been taken to correct the projection effects,which however led to an inflated average velocity probably due to the biased choice of CME *** order to estimate the overall influence of the projection effects on the kinematic properties of the CMEs,we perform a forward modeling of real distributions of CME properties,such as the velocity,the angular width,and the latitude,by requiring their projected distributions to best match *** a matching is conducted by Monte Carlo *** to the derived real distributions,we found that （1） the average real velocity of all non-full-halo CMEs is about 514 km s-1,and the average real angular width is about 3.°,in contrast to the corresponding apparent values of 418 km s-1 and 42.7° in observations;（2） For the CMEs with the angular width in the range of 20°-120°,the average real velocity is 510 km s-1 and the average real angular width is 43.4°,in contrast to the corresponding apparent values of 3.2 km s-1 and 52° in observations.

关键词： sun: coronal mass ejections (CMEs) -- methods: statistical -- methods:numerical

spatial distribution of metal emissions in supernova remnant 3. 3.7 viewed with Chandra and XMM

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science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 267-270页

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

We present X-ray equivalent width imaging of 3. 3.7 for Mg Heα,si Heα,s Heα,and Fe Kα complex lines with Chandra and XMM-Newton *** images revealed that the heavier the element is,the smaller the extent of the element distribution *** Mg emission is evidently enhanced in the southeastern blow-out region,well along the radio boundary there,and appears to partially envelope the eastern Fe *** bilateral hat-like si line-emitting structures are along the northern and southern borders,roughly symmetric with respect to the south-east-northwest elongation *** s line-emitting shell is located just inside the northern radio and IR shell,indicating a layer of reversely shocked sulphur in the ejecta.A few enhanced Fe features are basically aligned along the diagonal of the rectangular shape of the sNR,which implicates an early asymmetric sN explosion.

关键词： IsM 3. 3.7 G41.1-0.3 X-ray supernova remnants

A sTUDY ON THE RELATION BETWEEN THE VARIATION OF THE PRECIPITATION IN EAsTERN JIANGHUAI WATERsHED AND sEDIMENT TRANsPORT IN CHIHE RIVER VALLEY

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Chinese Geographical science 2002年第1期12卷 44-49页

作者： ZHANG Jian chun, PENG Pu zhuo(department of Urban and Resources sciences,nanjing university,nanjing 210093.P.R.china ) department of Urban and Resources sciences Nanjing University Nanjing P. R. China

Rainfall resource is very important to the development of society and economy,especially to eastern Jianghuai watershed which is now facing serious challenge of water shortage. Based on the observational records covering the period from 1957 to 1999,the characteristics of precipitation changing over eastern JiangHuai watershed and its connection to sediment discharge in Chihe River valley were studied using tendency analysis and correlation analysis .Results show that the rainfall in this area had a declining tendency in spring at a rate of -21.2mm/10a, annual and summer precipitation was increasing at the rate of 10.6mm/10a and 14.8mm/10a. The gray correlation analysis shows that sediment discharge correlates most closely with runoffs and the frequency of the rainstorm with a daily precipitation of 50-100mm, on the second place,with the rainfall and the frequency of the rainstorm of a daily precipitation no less than 100mm;and thirdly with the number of rainy days. In addition, the paper suggests the major countermeasures and methods for controlling of soil and water losses in this area.

关键词： eastern Jianghuai watershed Chihe River rainfall sediment discharge correlation grade

Extraction of the spectral information of terahertz signals using superconducting Josephson junction

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science china(Technological sciences) 2010年第5期53卷 1247-1251页

作者： XU WeiWei,CHEN Jian,KANG Lin & WU PeiHeng department of Electronic science & Engineering,nanjing university,nanjing 210093.china 1. department of Electronic science & Engineering Nanjing University Nanjing 210093 China

Using YBa2Cu3.7-δ/MgO bicrystal Josephson junction,we have developed a setup for spectrum analyses of terahertz signals,up to 2.5 THz,with a frequency resolution of 3.*** junction works at liquid nitrogen temperature when the signal frequencies are low while for signals at 1.6 THz and 2.5 THz the junction is cooled to 6 *** signal processing(DsP) chips are made use of to build a data acquisition and processing system so that it can be compact,fast,and *** the completion of the relevant hardwares and softwares,the measurements are now automated.

关键词： Josephson junction THz wave spectrum detection DsP technology

Karst conduit flow and its hydrodynamic characteristics——Houzhai River drainage basin in Fueling,Guizhou,china as an example

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Chinese science Bulletin 2001年第S1期46卷 45-51页

作者： WANG Lachun & ZHANG Yongzhandepartment, of Urban & Resource sciences, nanjing university, nanjing 210093. china Key Laboratory of Coast & Island Development of Ministry of Education of {3., nanjing university, nanjing 210093. china 1. department of Urban & Resource Sciences Nanjing University 210093 Nanjing China 2. Key Laboratory of Coast & Island Development of Ministry of Education of china Nanjing University 210093 Nanjing China

Conduit flow is a special geomorphologic and hydrological phenomenon in karst area. Houzhai River drainage basin in Puding, Guizhou Province is a large-scale test field in the main and broad karst area in the southern part of china, where conduit flow is a general reserve and drainage system for groundwater. Based on the great deal of field investigation and indoor research work during the 1970s-1980s, pulse tests were done four times there during 1988-1991 in wet and dry seasons. It shows that water level at each observation site changes from 10 to 1800 mm, with the larger variation in upper stream and at karst windows than in lower reaches and at each exit along subterraneous rivers. The average flow velocity in conduit system is determined within 200-800 m/h, with the less change from flood to dry seasons, and it is higher in principal conduits and in upper stream area. Also, the reliable divided discharge ratio among each hydrological conduit of sunken system has been got. Thus, combined with

关键词： conduit flow karst pulse test Houzhai River.

Effects　of　copper，manganese　and　pH　on　the　growth　and　several　enzyme　activities　of　mycorrhizal　fungus　Cenococcum　geophilum　Fr．

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Journal of Environmental sciences 1996年第4期8卷 419-425页

作者： Kong Fanxiang Zhang Min(department of Environmental science and Engineering, nanjing university,nanjing {3.china) department of Environmental science Nanjing University Nanjing 210093 China

he effects of various concentrations of copper,manganese and ph on the growth,protein content and several enzyme activities of mycorrhizal fungus Cenococcum geophilum Fr. Were *** results showed that high concentration of copper (20 mg/L)and low ph (3.0-4.0) inhibited the mycelial growth (dry weight), however, the protein content increased or not significantly reduced in mycelia after copper or manganese was applied. The activities of acid phosphatase and α-mannosidase were induced by high concentration of Mn (200-400 mg/L);but the activities of G6PDH, MTLDH and trehalase were inhibited by high content of copper(10-20 mg/L),both of the responses of these enzymes and mycelial growth under the presence of copper were correlative each other. Measurement of these enzyme activities might therefore provide a useful criterion for the evaluation of the fungitoxicity of soil contaminated by copper.

关键词： copper manganese ph mycorrhizal fungus enzyme activity.