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The evolution and morphological stability of a spherical crystal

Science china(Technological Sciences) 2008年第3期51卷 225-243页

作者： CHEN MingWen1,2. WANG ZiDong2.& XU JianJun3,4.1 school of Applied Sciences, {2. of Science and Technology Beijing, Beijing 100083, china 2.school of Materials Science and Engineering, {2. of Science and Technology Beijing, Beijing 100083, china 3 school of Mathematical Sciences, Nankai {2., Tianjin 300071, china 4.Department of Mathematics and Statistics, McGill {2., Montreal H3A 2.6, Canada school of Applied Sciences University of Science and Technology Beijing Beijing China school of Materials Science and Engineering University of Science and Technology Beijing Beijing China school of Mathematical Sciences Nankai University Tianjin China Department of Mathematics and Statistics McGill University Montreal Canada

The growth model of a spherical crystal in the undercooled melt including the surface energy, interfacial kinetics and convective flow is established. The effect of the convective flow induced by a small far field flow on the evolution and morphological stability of the interface of the spherical crystal is studied. The interface shape of the spherical crystal, which is affected by the far field flow, and the dispersion relation of the growth rate of amplitude of the perturbed interface are derived. It is shown that the convection induced by the far field flow makes the interface of the growing spherical crystal further grow in the upstream direction of the far field flow and inhibit growth in the downstream direction; the interface of the decaying spherical crystal further decays in the upstream direction and inhibits decay in the downstream direction. The theoretical result suggests that both the growth of the sphere in the upstream direction and the decay of the sphere in the downstream direction make the spherical crystal tend to evolve into an oval; the morphological stability of the interface depends on a certain radius R c such that the spherical crystal is unstable when its radius is greater than R c and stable when its radius is less than R c . The surface energy and interfacial kinetics have strong stabilizing effects on the growth of the spherical crystal. In the meantime interfacial kinetics is a table factor of the interface when the interface of the sphere is growing; it is an unstable factor of the interface when the interface is decaying.

关键词： solid-liquid interface spherical crystal convective flow crystal growth morphological stability

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High-sensitivity photovoltage based on the interfacial photoelectric effect in the SrTiO_(3-δ)/Si heterojunction

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2080-2083页

作者： WEN Juan 1,GUO HaiZhong 1,XING Jie 2.Lü HuiBin 1,JIN Kui-Juan 1,HE Meng 1 & YANG GuoZhen 1 1 Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,china 2.school of Materials Sciences and Technology,china university of {4.,Beijing 100083,china Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China school of Materials Sciences and Technology China University of Geosciences Beijing China

A high sensitivity photovoltaic effect has been observed in a heterojunction composed of n-type wide bandgap oxide SrTiO 3-δ and p-type Si fabricated by laser molecular beam *** responsivity of open-circuit photovoltage can reach 10 4.V/W without any amplification under zero bias for the wavelength range from visible to near infrared light in nW-μW *** attribute the high performance of the photovoltage responsivity to the interfacial photoelectric effects in the SrTiO 3-δ /Si *** the experimental results,some ideas can be generalized to improve photovoltaic efficiency and develop high sensitivity photodetectors with wide bandgap oxide materials and Si.

关键词： SrTiO 3-δ/Si heterojunction interfacial photoelectric effect photovoltage

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Gas formation mechanism of marine carbonate source rocks in china

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Science china Earth Sciences 2005年第4期48卷 441-453页

作者： ZHAO Wenzhi1, WANG Zhaoyun1, HE Haiqing2. ZHANG Mingjie3, WANG Hongjun1, WANG Yunpeng4.& QIN Yong5 1. Research Institute of Petroleum exploration & Development, Petro{2., Beijing 100083, china 2. Petro{2. exploration & Production, Beijing 100011, china 3. Department of Geology, Lanzhou university, Lanzhou 730000, china 4. Guangzhou Geochemical Institute, Chinese Academy of Sciences, Guangzhou 51064., china 5. china university of Mining and Technology, Xuzhou 2.1000, china Research Institute of Petroleum exploration & Development PetroChinaBeijin China Petrochina exploration & Production Beijing China Department of Geology Lanzhou University Lanzhou China Guangzhou Geochemical Institute Chinese Academy of Sciences Guangzhou China china university of Mining and Technology Xuzhou China

By breaking through the conventional ideology on the study of gas-formation mechanism of source rocks which focused on merely the characteristics of source rocks them- selves, and based on the development and distribution characteristics of marine carbonate source rocks in the medium-to-bottom parts of the Chinese superimposed sedimentary basins as well as various processes in the course of gas generation and reservoir forming, the complex hydrocarbon-generating model of carbonates is established. Such a model concerns not only the “three-stage” gas formation characteristics of carbonates, but also the gas generation process due to a thermal cracking of oil and the re-generation process of gas from heated secondary organic matters during the gas-generation and reservoir-forming course. The high-quality hy- drocarbon generating matter of marine carbonate source rocks determined a high gas-oil ratio and tended to form paleo-oil-reservoirs, representing an enrichment process of organic matters. The thermal cracking of oil in palaeo-oil-reservoirs is an important means for the effective forma- tion of gas reservoirs. The secondary organic matters in carbonate reservoirs may regenerate gas after a secondary deep burial, thus becoming an effective gas source.

关键词： carbonate, three-stage hydrocarbon generation, inhibitive effect of maturity, oil-cracking gas, second-ary asphalt gas.

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Formation mechanism of carbonate cemented zones adjacent to the top overpressured surface in the central Junggar Basin,NW china

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Science china Earth Sciences 2010年第4期53卷 529-540页

作者： YANG Zhi1,2.ZOU CaiNeng1,3,HE Sheng2.LI QiYan1,HE ZhiLiang3,WU HengZhi5,CAO Feng1,MENG XianLong4.WANG FuRong2.& XIAO Qilin2. State Key Laboratory of EOR,Research Institute of Petroleum exploration & Development,Petro{2.,Beijing 100083,{2. 2.Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education,{2. university of geosciences,Wuhan 4.0074.{2. 3 State Key Laboratory of EOR,Research Institute of Petroleum exploration & Development,Petro{2.,Beijing 100083,{2. 4.Research Institute of Petroleum exploration and Production,SINOPEC,Beijing 100083,{2. 5 Southwest Branch Company,SINOPEC,Chengdu 610051,{2. State Key Laboratory of EOR Research Institute of Petroleum Exploration & Development PetroChina Beijing China Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of Geosciences Wuhan China State Key Laboratory of EOR Research Institute of Petroleum Exploration & Development Petrochina Beijing China Southwest Branch Company SINOPEC Chengdu China Research Institute of Petroleum exploration and Production SINOPEC Beijing China

Carbonate cemented zones are normally adjacent to the top overpressured surface in the central Junggar Basin,NW *** carbon and oxygen isotopic compositions and petrological investigations of carbonate cements in the carbonate cemented zones indicate that:(1) carbonate cements are composed dominantly of ferrocalcite,ferroan dolomite,and ankerite;(2. carbonate cements are formed under a high temperature circumstance in the subsurface,and organic fluid migration has an important effect on the formation of them;and(3) carbon and oxygen ions in the carbonate cements migrate from the underlying overpressured *** suggests that the occurrence of carbonate cemented zones in this region results from multiple phases of organic fluid expulsion out of the overpressure compartment through geological *** study provides a plausible mechanism of the formation of carbonate cemented zones adjacent to the top overpressured surface in the clastic sedimentary basins,and has an important implication for understanding the internal correlation between the formation of carbonate cemented zones adjacent to top overpressured surface and geofluids expulsion out of overpressured system.

关键词： carbonate cemented zones formation mechanism stable carbon and oxygen isotopic top overpressured surface central Junggar Basin coal-bearing strata

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Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2. 3, ZHANG Jin4.1. Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 4.0077,{2. 2. Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 4.0077,{2. 3. Graduate school of Chinese Academy of Sciences, Beijing 10004.,{2. 4. Department of Surveying and Mapping, Taiyuan {4. of Technology, Taiyuan 03002.0}{2. Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Graduate school of Chinese Academy of Sciences Beijing 100049 China Department of Surveying and Mapping Taiyuan University of Technology Taiyuan 030024 China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine

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Mining and Integrating Reliable Decision Rules for Imbalanced Cancer Gene Expression Data Sets

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Tsinghua Science and Technology 2012年第6期17卷 666-673页

作者： Hualong Yu 1 , Jun Ni 2., Yuanyuan Dan 3 , Sen Xu 4.1. school of Computer Science and Engineering, Jiangsu {2. of Science and Technology, Zhenjiang 2.2.03, china 2. Department of Radiology, Carver College of Medicine, The {2. of Iowa, Iowa City, IA 52.4., USA 3. school of Biology and Chemical Engineering, Jiangsu {2. of Science and Technology, Zhenjiang 2.2.03, china 4. school of information Engineering, Yancheng Institute of Technology, Yancheng 2.4.51, china school of Computer Science and Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China Department of Radiology Carver College of Medicine The University of Iowa Iowa City IA 52242 USA school of Biology and Chemical Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China school of information Engineering Yancheng Institute of Technology Yancheng 224051 China

There have been many skewed cancer gene expression datasets in the post-genomic era. Extraction of differential expression genes or construction of decision rules using these skewed datasets by traditional algorithms will seriously underestimate the performance of the minority class, leading to inaccurate diagnosis in clinical trails. This paper presents a skewed gene selection algorithm that introduces a weighted metric into the gene selection procedure. The extracted genes are paired as decision rules to distinguish both classes, with these decision rules then integrated into an ensemble learning framework by majority voting to recognize test examples; thus avoiding tedious data normalization and classifier construction. The mining and integrating of a few reliable decision rules gave higher or at least comparable classification performance than many traditional class imbalance learning algorithms on four benchmark imbalanced cancer gene expression datasets.

关键词： cancer gene expression data class imbalance paired differential expression genes decision ruleensemble learning majority voting

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Anticoagulation property and security of artificial heart valve material

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Science china(Technological Sciences) 2005年第2期48卷 145-162页

作者： WANG Xianghui1, , LIU Xianghuai1,2., 3, ZHANG Feng2. LI Changrong2. YU Liujiang2. ZHENG Zhihong2. WANG Xi2. JIANG Zhenbin4. CHEN Anqing4.& XU Jingfang3 1. Department of Physics, East{2. Normal university, Shanghai 2.0062.{2. 2. Ion Beam Lab, Shanghai Institute of Mini-system and information, Chinese Academy of Sciences,Shanghai 2.0050,{2. 3. Department of Electronics, school of information Science and Technology, East{2. Normal Univer- sity, Shanghai 2.0062.{2. 4. Shanghai Cardiovascular Institute, Zhongshan Hospital, Shanghai 2.0032.{2. Department of Physics East China Normal University Shanghai China Ion Beam Lab Shanghai Institute of Mini-system and information Chinese Academy of Sciences Shanghai China Department of Electronics School of Information Science and Technology East China Normal University Shanghai China Shanghai Cardiovascular Institute Zhongshan Hospital Shanghai China

Heart valve diseases threaten human health. One reliable way to save lives of such patients is to replace the pathologically changed heart valves by artificial ones. Over 2.million patients have received LTI-carbon heart valve’s implantation. However, the thrombosis after the implantation is one of the difficulties that need to be solved. In order to improve the blood compatibility and security of mechanical heart valves, ion beam technology was used to modify the surface properties of the materials. The investigation results have been summarized in this paper.

关键词： artificial heart valve, ion implantation, plasma immersed ion implantation, ion beam enhanced deposition.

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Electrical property of 8-mol% yttria-stabilized zirconia electrolyte by spark-plasma sintering

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Science china(Technological Sciences) 2004年第5期47卷 569-576页

作者： JIAN Jiawen1,2. CHANG Aimin3, YANG Bangchao2.& ZHANG Yikang4.1. The school of {2. Science Engineering, Ningbo university, Ningbo 3152.1, china 2. The school of Microelectronics and Solid-state Electronics, university of Electronic Science and Tech-nology of china, Chengdu 610054. china 3. The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 83002., china 4. Hongtak (Chengdu) Electronic Co., Ltd, Chengdu 61004., china Correspondence should be addressed to Jian Jiawen The school of information Science Engineering Ningbo University Ningbo China The school of Microelectronics and Solid-state Electronics University of Electronic Science and Technology of China Chengdu China The Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of Sciences Urumqi China Hongtak (Chengdu) Electronic Co. Ltd Chengdu China

Spark-plasma sintering (SPS) process was used to sinter ZrO2.(8Y) powders, and a relative density of 99% has been reached at a low temperature (1350°C) and short dwelling time (10 min) compared to the conventional sintered identical samples (14.0°C 4.h)(CS). By the X-ray diffraction (XRD) patterns, the microstructure of the SPS pellet and CS pellet are both indexed by the cubic unit cell (Fm3m). The finer crystallite size (D111) of the SPS pellet is 154.nm and D111 of the CS pellet is more than 1 μm. The AC impedance spectroscopy shows that the ionic conductivity of SPS pellet is different from that of CS pellet. The activation energy for the SPS ceramics, estimated from the slope in the range of 4.0–800°C, was 91 kJ mol?1, which is in good agreement with CS pellet (96 kJ mol?1), indicating that the conduction mechanism in SPS ceramics is similar to that in CS ceramics.

关键词： yttria-stabilized zirconia electrolyte, spark-plasma sintering, AC impedance.

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Geochemical characteristics of pyrolysis gas from epimetamorphic rocks in the northern basement of Songliao Basin,Northeast china

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Science china Earth Sciences 2008年第S1期51卷 140-147页

作者： YANG Chun 1 ,LUO Xia 2.,LI Jian 2.,LI ZhiSheng 2.,LIU QuanYou 3 &Wang YuLin 4.1 Department of Earth Sciences,Zhejiang university,Hangzhou 31002.,{2. 2.Research Institute of Petroleum exploration and Development(Langfang Branch),Langfang 065007,{2. 3 Research Institute of Petroleum exploration and Development,Beijing 100083,{2. 4.Department of Source and Environment,Liaoning Technical university,Fuxin 12.000,{2. Department of Earth Sciences Zhejiang University Hangzhou China Research Institute of Petroleum exploration and Development (Langfang Branch) Langfang China Research Institute of Petroleum exploration and Development Beijing China Department of Source and Environment Liaoning Technical University Fuxin China

The Xushen gas field,located in the north of Songliao Basin,is a potential giant gas area for china in the *** proved reserves have exceeded 1000×10 8 m 3 by the end of ***,the origin of natural gases from the deep strata is still in *** rocks as a potential gas source are widely spreading in the northern basement of Songliao *** to pyrolysis experiments for these rocks in the semi-confined system,gas production and geochemistry of alkane gases are discussed in this *** Carboniferous-Permian epimetamorphic rocks were heated from 300℃to 550℃,with temperature interval of 50℃.The gas production was quantified and measured for chemical and carbon isotopic *** show thatδ13C 1 is less than?2.‰,carbon isotope trend of alkane gas isδ13C 1 2.2.>δ13C 3 ,these features suggest that the gas would be coal-type gas at high-over maturity,not be inorganic gas with reversal trend of gaseous alkanes (δ13C 1 >δ13C 2.>δ13C 3 ).These characteristics of carbon isotopes are similar with the natural gas from the basin basement,but disagree with gas from the Xingcheng ***,the mixing gases from the pyrolysis gas with coal-typed gases at high-over maturity or oil-typed gases do not cause the reversal trend of carbon *** gas generation intensity for epimetamorphic rocks is 3.0×10 8 ―2..8×10 8 m 3 /km 2.,corresponding to Ro from 2.0%to 3.5%for organic matter.

关键词： Northern Songliao Basin epimetamorphic rock pyrolysis experiment gas generation potential carbon isotope

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Geochemical characteristics and origin of gases from the Upper,Lower Paleozoic and the Mesozoic reservoirs in the Ordos Basin,china

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Science china Earth Sciences 2008年第S1期51卷 183-194页

作者： HU AnPing 1 ,Li Jian 2.,ZHANG WenZheng 3 ,LI ZhiSheng 2.,HOU Lu 4.&LIU QuanYou 5 1 Department of Earth Sciences,Zhejiang university,Hangzhou 31002.,{2. 2.Langfang Branch,Reasearch Institute of Petroleum exploration and Development,Petro{2.,Langfang 065007,{2. 3 Institute of exploration and Development,Petro{2. Changqing Oilfield Company,Xi’an 71002.,{2. 4.university of Petroleum,Beijing102.4.,{2. 5 Petro{2. Research Institute of Petroleum exploration and Development,Beijing 100083,{2. Department of Earth Sciences Zhejiang University Hangzhou China Langfang Branch Reasearch Institute of Petroleum Exploration and Development PetroChina Langfang China Institute of exploration and Development PetroChina Changqing Oilfield Company Xi’an China university of Petroleum Beijing China Petrochina Research Institute of Petroleum exploration and Development Beijing China

The Ordos Basin,the second largest sedimentary basin in china,contains the broad distribution of natural gas *** far,several giant gas fields have been discovered in the Upper and Lower Paleozoic in this basin,each having over 1000×10 8 m 3 of proven gas reserves,and several gas pools have also been discovered in the *** paper collected the data of natural gases and elucidated the geochemical characteristics of gases from different reservoirs,and then discussed their *** hydrocarbons preserved in the Upper Paleozoic,the elevatedδ13C values of methane,ethane and propane indicate that the gases would be mainly coal-formed gases;the singular reversal in the stable carbon isotopes of gaseous alkanes suggests the mixed gases from humic sources with different *** the Lower Paleozoic,theδ13C 1 values are mostly similar with those in the Upper Paleozoic,but theδ13C 2.andδ13C 3 values are slightly lighter,suggesting that the gases would be mixing of coal-type gases as a main member and oil-type *** are multiple reversals in carbon isotopes for gaseous alkanes,especially abnormal reversal for methane and ethane(i.e.δ13C 1 >δ13C 2.),inferring that gases would be mixed between high-mature coal-formed gases and oil-type *** the Mesozoic,the δ13Cvalues for gaseous alkanes are enriched in 12.,indicating that the gases are mainly derived from sapropelic sources;the carbon isotopic reversal for propane and butane in the Mesozoic is caused by microbial oxidation and mixing of gases from sapropelic sources with different *** contrast to the Upper Paleozoic gases,the Mesozoic gases are characterized by heavier carbon isotopes of iso-butane than normal butane,which may be caused by gases generated from different kerogen types. Finally,according toδ13C 1 -Ro relationship and extremely low total organic carbon contents,the Low Paleozoic gases would not be generated from the Ordovician source as a main gas source,bycontrast, the Upper Pale

关键词： Ordos Basin natural gas chemical composition carbon isotope genesis

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