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Determination of vertical gradient of gravity anomaly with topographic data

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chinese Science Bulletin 1999年第11期44卷 1029-1034页

作者： zhang Chijun{1. of {2. and {3. , chinese academy of Sciences , wuhan 43.077 , china institute of {1. and {2. Chinese Academy of Sciences Wuhan China

The role of vertical gradient of gravity anomaly in the solution and interpretation of geological and geophysical problems on superficial layer is increasingly evident. However, it is difficult to directly observe the vertical gradient of gravity anomaly in mountainous area. Moreover,aerial and satellite gravity gradient measurments have not been put into practice up to date *** vertical gradient of gravity anomaly is calculated by use of topographic data and several problems concerned are investigated and discussed. It turns out in theory and practice that the relative error of the vertical gradient determined with the method is only 5%, and when the vertical gradient of gravity anomaly reaches the maximum 1.000 ns-2./sup> the error is only 50 ns-2./sup>. In addition, how to divide ring zones in calculation and the errors caused by the inaccuracy of landform elevation and rock density has been quantitatively analysed.

关键词： vertical gradient gravity anomaly topographic mass geoid.

A Feedback-Based Web Search Engine

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wuhan University Journal of Natural Sciences 2004年第5期9卷 561-568页

作者： zhang Wei-feng 1,2.3., XU Bao-wen 2.3.4 , ZHOU {3.-yu 2.3.4 1. Department of Computer Science and Engineering, Nan{2.g University of Posts and Telecommunications, Nan{2.g 2.0003. Jiangsu, china 2. Department of Computer Science and Engineering, Southeast University, Nan{2.g 2.0096, Jiangsu, china 3. Jiangsu {13. of Software Quality, Nan{2.g 2.0096 Jiangsu, china 4. The State Key Laboratory of Software Engineering, wuhan University, wuhan 43.072. Hubei, china Department of Computer Science and Engineering Nanjing University of Posts and Telecommunications . Nanjing 210003 Jiangsu China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. Key words WWW - search engine - query reconstruction - feedback CLC number TP 3.1. 13..4 Foundation item: Supported by the National Natural Science Fundation of china (603.3.66). National Grand Fundamental Research 973.Program of china (2.02.B3.2.0). Opening Foundation of State Key Laboratory of Software Engineering in {2. University, Opening Foundation of Jiangsu Key Laboratory of Computer Information Processing Technology in Soochow UniversityBiography: zhang Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

Zijinshan-Bitian Cu-Au-Mo orefield, SW Fujian——An example of gold-rich PCS zoning

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chinese Science Bulletin 1999年第S2期44卷 134-135页

作者： QI Jianzhong~1, LI Zhaonai~2. zhang Dequan~3. FANG Xiheng~4 and xiao Huiliang~1 1. Nan{2.g institute of Geology and Mineral Resources, chinese academy of Geological Sciences, Nan{2.g 2.0016, china 2. institute of Geology, chinese academy of Geological Sciences, Bei{2.g 10003., china 3. institute of Mineral Deposits, chinese academy of Geological Sciences, Bei{2.g 10003., china 4. institute of Geology, Ministry of Nuclear Industry, Bei{2.g 100013. china Nanjing {1. of Geology and Mineral Resources Chinese Academy of Geological Sciences Nanjing 210016 China institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing 100037 China institute of Geology Ministry of Nuclear Industry Beijing 100013 China

THE Zijinshan-Bitian Cu-Au-Mo orefield is spread to north of the Shanghang County, SW *** geological structure it is located at the plunging end of NE-trending Xuanhe anticlinorium, in the NE rim ofthe NW trending Shanghang volcano-sedimentary basin. Orefield basement is composed of the Archean-Middle Proterozoic low-grade metamorphic rock formations, containing marine basic metavolcanic sequenses. Lower Cretaceous subaerial volcanic rocks of andesite-trachy andesite-rhyolite composition fill inthe volcano-sedimentary basin. Pre-mineralization granitic batholith dated 1.5Ma（Rb-Sr）and 1.7Ma（U-Pb） occupies the axial part of the plunging anticlinorium, which was regarded as crust-remelting typegranitoids. Mineralization-affiliated subvolcanic dacite porphyrite, co-volcanic granodiorite and quartzdiorite porphyrite （1.{1.{1.Ma（Rb-Sr）, Sr1./sub> = 0.708 9） belong to syntactic type in genesis and

关键词： gold-rich porphyre copper system zoning Fujian Zijinshan.

Optimization for epitaxial fabrication of infinite-layer nickelate superconductors

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Frontiers of physics 2024年第3期19卷 61-69页

作者： Minghui Xu Yan Zhao Xiang Ding Huaqian Leng Shu zhang {1. Gong Haiyan {2. {2.tao Zu Huiqian Luo Ke-jin Zhou Bing Huang Liang Qiao School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China Beijing Computational Science Research Center Beijing 100193China Diamond Light Source Harwell CampusDidcot OX110DEUnited Kingdom Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

The discovery of nickelates superconductor creates exciting opportunities to unconventional superconductivity. However, its synthesis is challenging and only a few groups worldwide can obtain samples with zero-resistance. This problem becomes the major barrier for this field. From plume dynamics perspective, we found the synthesis of superconducting nickelates is a complex process and the challenge is twofold, i.e., how to stabilize an ideal infinite-layer structure Nd_(0.8)Sr_(0.2.NiO_(2., and then how to make Nd_(0.8)Sr_(0.2.NiO_(2. superconducting? The competition between perovskite Nd_(0.8)Sr_(0.2.NiO_(3. and Ruddlesden−Popper defect phase is crucial for obtaining infinite-layer structure. Due to inequivalent angular distributions of condensate during laser ablation, the laser energy density is critical to obtain phase-pure Nd_(0.8)Sr_(0.2.NiO_(3.. However, for obtaining superconductivity, both laser energy density and substrate temperature are very important. We also demonstrate the superconducting Nd_(0.8)Sr_(0.2.NiO_(2. epitaxial film is very stable in ambient conditions up to 51.0}days. Our results provide important insights for fabrication of superconducting infinite-layer nickelates towards future device applications.

关键词： nickelate superconductivity infinite-layer plasma condensate plume dynamics

Synthesis and structural characterization of Zn_3._{1.powder

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Science china(Physics,Mechanics & Astronomy) 2005年第2期48卷 201-210页

作者： ZONG Fujian1. MA Honglei1. XUE Chengshan2. ZHUANG Huizhao2. zhang Xijian1. MA {3.1. JI Feng1.& {2. Hongdi1.1. School of Physics and Microelectronics, Shandong University, {3.an 2.01.0, china 2. institute of Semiconductor, Shandong Normal University, {3.an 2.001., china School of Physics and Microelectronics Shandong University Jinan 250100 China institute of Semiconductor Shandong Normal University Jinan 250014 China

Zinc nitride (Zn3.{1. powder has been synthesized through the nitridation reaction of Zn powder with NH3.gas (at the flow rate of 500 ml/min) at the nitridation temperature of 600℃ for 1.1. min. X-ray diffraction (XRD) indicates that Zn3.{1.is cubic in structure with the lattice constant being a = 0.9788 nm. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that Zn3.{1.powder has surface morphology of various types. X-ray photoelectron spectroscopy (XPS) shows the differences in chemical bonding states between Zn3.{1.and ZnO, and confirms the formation of N–Zn bonds. Observation through high resolution transmission electron microscopy (HRTEM) also indicates that the computer simulation of the structure of Zn3.{1.is consistent with the structural model put forward by Partin.

关键词： nitridation, Zn3.2 powder, structure, XRD, SEM, TEM, HRTEM, XPS.

A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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Science china Earth Sciences 2010年第5期53卷 763-772页

作者： CHEN BaiLian1,3. zhang RenHe2. SUN ShuFen1, BIAN LinGen2. {3. CunDe4,2.& zhang TingJun5 1 institute of Atmospheric Physics, chinese academy of Sciences, Beijing 10002., china 2.chinese academy of Meteorological Sciences, Beijing 100081, china 3.Graduate University of chinese academy of Sciences, Beijing 100049, china 4 Cold and Arid Regions Environmental and Engineering Research institute, chinese academy of Sciences, Lanzhou 73.000, china 5 The National Snow and Ice Data Center, University of Colorado, Boulder, CO 803.9-0449, USA 1. institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Chinese Academy of Meteorological Sciences Beijing 100081 China4. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China5. The National Snow and Ice Data Center University of Colorado Boulder CO 80309-0449 USA

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°2.′S, 70°2.′E), we applied the model to simulate the seasonal temperature variation within a depth of 2. m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1. 1. 3. 1. m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1. the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2. the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

Discovery of seep carbonate nodules as new evidence for gas venting on the northern continental slope of South china Sea

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chinese Science Bulletin 2006年第10期51卷 1228-1237页

作者： CHEN Zhong1,2.3. YAN Wen1,2.3. CHEN Muhong1,3. WANG Shuhong1,2.3. LU Jun1,3. {3. Fan1,3. XIANG Rong1,3. xiao Shangbin1,3. YAN Pin1,2.3.& GU Senchang1,2.3.1. South{2. Sea institute of Oceanology, chinese academy of Sci-ences, Guangzhou 5103.1,{2. 2. Guangzhou Center for Gas Hydrate Research, chinese academy of Sciences, Guangzhou 5103.1,{2. 3. Key Laboratory of Marginal Sea Geology, South{2. Sea institute of Oceanology and Guangzhou institute of Geochemistry, chinese academy of Sciences, Guangzhou 5103.1,{2. South china Sea {1. of Oceanology Chinese Academy of Science Guangzhou China Guangzhou Center for Gas Hydrate Research Chinese Academy of Sciences Guanzhou China Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology and Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Seep carbonate nodules were firstlycollected from the southwestern Dongsha area onnorthern continental slope of South china Sea formineralogical and geochemical studies. The resultsof X-ray diffraction show that carbonate nodules arecomposed of Fe-rich domolite,siderite and a few cal-cite and aragonite, as well as a small quantity ofnon-carbonate minerals such as goethite, quartz andclay minerals. Fe-rich dolomite and siderite charac-terized by euhedral microcrystalline structure weredirectly precipitated at cold seeps. The δ 1.1. valuesfor Fe-rich dolomite and siderite in the bulk nodulesvary from ?1..2.‰ to ?{1..07‰, and the δ 1.O valuesrange from 0.42.to 2.76‰. Their moderate depleted1.1. reflects that carbon origin is possibly thermoge- netic gas or mixed gas, which is evidence of gasventings in the seafloor. Moreover, massive wormtube fossils related to cold seeps were found on thesurfaces of carbonate nodules, and the conduitsand/or channels in semi-solidified nodules whichwere not filled by carbonate or sediment were alsoobserved. A preliminary conclusion is that activemicro gas venting with a conduit/channel diameterrange from 2.0 μm to 600 μm possibly exists inmodern seafloor of the carbonate nodule area.

关键词：渗出碳酸盐节碳氧同位素甲烷渗漏天然气水化物

X-ray spectra induced in highly charged 40Ar^q+ interacting with Au surface

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 203-212页

作者： zhang xiao’an1,2. xiao Guoqing1, YANG Zhihu1, CHEN Ximeng3. ZHAO Yongtao1, LI Fuli4, zhang Yinping1, CUI Ying3. zhang Hongqiang3. XU Xu3. SHAO Jianxiong3.& ZHAN Wenlong11. institute of Modern Physics, chinese academy of Sciences, Lanzhou 73.000, china 2. Department of Physics, Xianyang Normal University, Xianyang 712.00, china 3. Department of Modern Physics, Lanzhou University, Lanzhou 73.000, china 4. Department of Applied Physics, Xi’an Jiaotong University, Xi’an 710049, china 1. institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. Department of Physics Xianyang Normal University Xianyang 712000 China 3. Department of Modern Physics Lanzhou University Lanzhou 730000 China 4. Department of Applied Physics Xi’an Jiaotong University Xi’an 710049 China

By use of optical spectrum technology, the spectra of X-ray induced by highly charged 40Arq+ ions interacting with Au surface have been studied. The results show that the argon Kα X-ray were emitted from the hollow atoms formed below the surface. There is a process of multi-electron exciting in neutralization of the Ar1.+ion, with electronic con-figuration 1.2.in its ground state below the solid surface. The yield of the projectile Kα X-ray is related to its initial electronic configuration, and the yield of the target X-ray is related to the projectile kinetic energy.

关键词： highly charged ion hollow multi-electron excitation X- ray.

The role of reservoir mediums in natural oil cracking:Preliminary experimental results in a confined system

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chinese Science Bulletin 2010年第33期55卷 3787-3793页

作者： xiao QiLin1,2.SUN YongGe1,3.& zhang YongDong1,2.1 State Key Laboratory of Organic Geochemistry,Guangzhou {2. of Geochemistry,chinese academy of Sciences,Guangzhou 510640,china 2.Graduate Schools,chinese academy of Sciences,Beijing 100049,china 3.{2. of Environmental and Biogeochemistry(eBig),Zhejiang University,Hangzhou 3.002.,china State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Graduate Schools Chinese Academy of Sciences Beijing 100049 China institute of Environmental and Biogeochemistry (eBig) Zhejiang University Hangzhou 310027 China

Large amounts of data regarding the influence of temperature and pressure on the thermal stability of crude oil have been pub-lished;however,the role of reservoir mediums has received little *** involving oil cracking in the presence of montmorillonite,illite,calcite,quartz and water were conducted in closed gold tubes to investigate the effects of these reservoir mediums on oil *** was done by screening variations in the chemical and stable carbon isotopic components of nC1.+ and gasoline-range hydrocarbons(nC8-)present in various *** indicated that reservoir mediums have an active role in oil cracking under experimental *** concentrations of nC1.+ in the cracked residues progressively decreased in systems containing oil+water+illite,oil+water+montmorillonite,oil+water,oil+water+quartz and oil+water+*** comparison with the system containing oil+water,our results indicated a retardation effect for oil cracking in systems in the presence of illite and montmorillonite,and an acceleration effect on oil destruction in systems in the presence of calcite and ***1.+ became increasingly depleted in 1.0} in systems with oil+water+illite,oil+water+calcite,oil+water+montmorillonite,oil+water+ quartz and oil+*** obvious correlation was observed between concentrations and stable carbon isotopic components of nC6-nC8 and nC1.+ in the individual *** discrepancies in chemical and stable carbon isotopic components of nC6-nC8 and nC1.+ in the pyrolyzed residues highlighted the important role of reservoir mediums to control carbon-carbon cleavage of nC1.+ and then the isomerization,cyclolization and aromatization reactions;as well as governing the occurrence and thermal destruction of nC6-nC8 under experimental *** research may have critical implications in reconstructing chemical kinetic models for natural oil cracking.

关键词：裂解作用实验条件密闭系统原油裂解水库介质天然同位素组成