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Science china(Technological Sciences) 2010年第9期53卷 2323-2327页

作者： BAO XiaoQian,GAO XueXu,ZHU Jie & ZHOU ShouZeng State key laboratory for Advanced Metals and Materials,University of Science and Technology {2.,{2. 100083.china State key laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing China

Nd12.3Fe81.7-xZrxB6.0 (x=0,1.5) and (NdDyTb)12.3(FeZrNbCu)81.7-yCoyB6.0 (y=0,12. ribbons were prepared by melt spinning at 2. m/s and subsequent *** influences of Zr,Dy/Tb and Co substitutions on magnetic properties and spin reorientation transitions of nanophase Nd2.e14B have been systematically *** with Zr-free sample,the remanence,intrinsic coercivity and maximum energy product for Nd12.3Fe80.2.r1.5B6.0 ribbon increase by 10.8 %,17.8 % and 60.2.%,*** significant improvement of magnetic properties originates from the finer grains of the sample by introducing Zr,which leads to the stronger exchange coupling between neighboring *** intrinsic coercivity for (DyTb)-substituted ribbon is significantly increased although the remanence is reduced,which could be compensated by the substitution of Co for *** spin reorientation temperature Tsr of nanocrystalline Nd2.e14B alloys was determined by measuring the ac magnetic *** was found to be lower than that of bulk *** substitutions of Zr,Dy/Tb and Co result in reduction of *** smaller the grain size,the lower the Tsr will *** of spin reorientation on magnetization characteristics of nanophase Nd2.e14B was discussed.

关键词： nanocrystalline Nd-Fe-B magnet exchange coupling spin reorientation transition magnetic properties

A tentative study for the prediction of the CME related geomagnetic storm intensity and its transit time

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Science china(Technological Sciences) 2005年第6期48卷 648-668页

作者： ZHAO Xinhua1,2.& FENG Xueshang1,3 1. SIGMA Weather Group, key laboratory of Space Weather, Center for Space Science and Applied Re-search, Chinese Academy of Sciences, {2. 100080, china 2. Graduate School of the Chinese Academy of Sciences, {2. 100039, china 3. School of Geophysics and Geoinformation Systems, china University of Geosciences, beijing 100083. china SIGMA Weather Group Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of Sciences Beijing China School of Geophysics and Geoinformation Systems China University of Geosciences Beijing China

Using 80 CME-ICME events during 1997.1―2.02.9, based on the eruptive source locations of CMEs and solar magnetic field observation at the photosphere, a current sheet magnetic coordinate (CMC) system is established in order to study the propagation of CME and its geoeffectiveness. In context of this coordinate system, the effect of the eruptive source location and the form of heliospheric current sheet (HCS) at the eruptive time of CME on the geomagnetic storm intensity caused by CME and the CME’s transit time at the Earth is investigated in detail. Our preliminary conclusions are: 1) The geomagnetic disturbances caused by CMEs tend to have the so-called “same side-opposite side effect”, i.e. CMEs erupt from the same side of the HCS as the earth would be more likely to arrive at the earth and the geomagnetic disturbances associated with them tend to be of larger magnitude, while CMEs erupting from the opposite side would arrive at the earth with less probability and the corresponding geomagnetic disturbance magnitudes would be relatively weaker. 2. The angular separation between the earth and the HCS affect the corresponding disturbance intensity. That is, when our earth is located near the HCS, adverse space weather events occur most probably. 3) The erupting location of the CME and its nearby form of HCS will also affect its arrival time at the earth. According to these conclusions, in this context of CMC coordinate we arrive at new prediction method for estimating the geomagnetic storm intensity (Dstmin) caused by CMEs and their transit times. The application of the empirical model for 80 CME-ICME events shows that the relative error of Dst is within 30% for 59% events with Dstmin≤?50 nT, while the averaged absolute error of transit time is lower than 10 h for all events.

关键词： coronal mass ejections, current sheet magnetic coordinate system, geomagnetic storm intensity, transit time, prediction method.

Indentation Size Effect on the Mechanical Properties of Supersonic Plasma Sprayed NiCr-Cr_3C_2.Coating

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稀有金属材料与工程 2012年第S1期41卷 296-298页

作者： Zhu Lina1,2.Xu Binshi2.Wang Haidou2.Wang Chengbiao1 1 School of Engineering and Technology,china University of Geosciences,beijing {2.china 2.National key laboratory for Remanufacturing,Academy of Armored Forces Engineering,beijing 100072.china Acad Armored Forces Engn Natl Key Lab Remfg Beijing 100072 Peoples R China china Univ Geosci Sch Engn & Technol Beijing 100083 Peoples R China

In this paper,NiCr-Cr3C2.coating was deposited onto AISI 1045 steel substrate by employing supersonic plasma spraying *** surface and cross-section morphologies of the NiCr-Cr3C2.coating were observed by *** phase constituents of the coating were identified by *** SEM images showed that the coating was very dense,and it had a low porosity *** XRD pattern implied that the coating was mainly composed of NiCr,Cr3C2.and *** tests were performed on the coating surface by a Nano *** widely used Oliver-Pharr method was adopted to extract the mechanical properties of the *** hardness exhibited a strong peak-load-dependence,*** size effect;the elastic modulus was not affected by indentation size effect.

关键词： nanoindentation mechanical property indentation size effect

Pyridine-H_5PMo_(10)V_2._(40) hybrid catalysts for liquid-phase hydroxylation of benzene to phenol with molecular oxygen

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Science china Chemistry 2009年第8期52卷 1264-1269页

作者： GE HanQing1,LENG Yan1,ZHANG FuMin1,PIAO JiaRui2.ZHOU ChangJiang1 & WANG Jun1 1 State key laboratory of Materials-Oriented Chemical Engineering,College of Chemistry and Chemical Engineering,Nanjing University of Technology,Nanjing 2.0009,{2. 2.Petrochemical Research Institute,petrochina Company Ltd.,beijing 100083.{2. State key laboratory of Materials-Oriented Chemical Engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing China Petrochemical Research Institute PetroChina Company Ltd. Beijing China

Pyridine(Py)-modified Keggin-type vanadium-substituted heteropoly acids(PynPMo10V2.40,n=1 to 5) were prepared by a precipitation method as organic/inorganic hybrid catalysts for direct hydroxylation of benzene to phenol in a pressured batch reactor and their structures were detected by *** various catalysts,Py3PMo10V2.40 exhibits the highest catalytic activity(yield of phenol,11.5%),without observing the formation of catechol,hydroquinone and benzoquinone in the reaction with 80 vol% aqueous acetic acid,molecular oxygen and ascorbic acid used as the solvent,oxidant and reducing reagent,*** of reaction temperature,reaction time,oxygen pressure,amount of ascorbic acid and catalyst on yield of phenol were investigated to obtain the optimal reaction conditions for phenol *** can greatly promote the catalytic activity of the Py-free catalyst(H5PMo10V2.40),mostly because the organic π electrons in the hybrid catalyst may extend their conjugation to the inorganic framework of heteropoly acid and dramatically modify the redox properties,at the same time,pyridine adsorbed on heteropoly acids can promote the effect of "pseudo-liquid phase",thus accounting for the enhancement of phenol yield.

关键词： hydroxylation benzene organic/inorganic hybrid catalyst phenol heteropoly acid pyridine

Rashba electron transport in one-dimensional quantum waveguides

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Science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 16-23页

作者： LIU DuanYang 1 , XIA JianBai 1,2.& CHANG YiaChung 2.1 State key laboratory for Superlattices and Microstructures, Institute of Semiconductors,{2. 2.Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan 1152., china State key laboratory for Superlattices and Microstructures Institute of Semiconductors Beijing China Research Center for Applied Sciences Academia Sinica Taipei Taiwan China

The properties of Rashba wave function in the planar one-dimensional waveguide are studied, and the following results are obtained. Due to the Rashba effect, the plane waves of electron with the energy E divide into two kinds of waves with the wave vectors k 1 =k 0 +k δ and k 2.=k 0 -k δ , where k δ is proportional to the Rashba coefficient, and their spin orientations are +π/2.(spin up) and -π/2.(spin down) with respect to the circuit, respectively. If there is gate or ferromagnetic contact in the circuit, the Rashba wave function becomes standing wave form exp(±ik δ l)sin[k 0 (l-L)], where L is the position coordinate of the gate or contact. Unlike the electron without considering the spin, the phase of the Rashba plane or standing wave function depends on the direction angle θ of the circuit. The travel velocity of the Rashba waves with the wave vector k 1 or k 2.are the same hk0/m * . The boundary conditions of the Rashba wave functions at the intersection of circuits are given from the continuity of wave functions and the conservation of current density. Using the boundary conditions of Rashba wave functions we study the transmission and reflection probabilities of Rashba electron moving in several structures, and find the interference effects of the two Rashba waves with different wave vectors caused by ferromagnetic contact or the gate. Lastly we derive the general theory of multiple branches structure. The theory can be used to design various spin polarized devices.

关键词： Rashba wave function one-dimensional waveguide boundary condition

Calculation of maximum ground movement and deformation caused by mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 562-569页

作者： LI Pei-xian1, 2. TAN Zhi-xiang1, 2. DENG Ka-zhong1, 2.1. key laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping, {2. University of Mining and Technology, Xuzhou 2.1116, {2. 2. Jiangsu key laboratory of Resources and Environmental Information Engineering, {2. University of Mining and Technology, Xuzhou 2.1116, {2. key laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China Jiangsu key laboratory of Resources and Environmental Information Engineering China University of Mining and Technology Xuzhou 221116 China

In order to know the maximum mining ground deformation of arbitrary surface point, directions of the maximum surface tilt, curvature,horizontal displacement and horizontal deformation caused by multi-working faces were deduced based on probability integral method. The distribution forms of surface deformations in all direction φ∈[0, 2.] were obtained and also equations of maximum deformations were given based on calculation of mining ground deformation in direction φ. A mining subsidence analysis system was developed with VB6.0. The system implements the probability integral mining subsidence prediction with direct integration method, and it can avoid errors of arbitrary shaped working face subdivision of traditional method, and accuracy of mining subsidence prediction can be improved with the direct integral method. The system implements the contour chart and profile chart and also data analysis automation by manipulation of the SURFER kernel function and it complements the defect of existing subsidence prediction software. Calculation of maximum deformations caused by multi-working faces mining in a coal mine of Xuzhou, china was shown as application example. Engineering application indicates that maximum deformation of mining ground surface can be calculated and analyzed by the system. The research provides a theoretical basis and calculation tool for mining subsidence prediction and analysis.

关键词： mining subsidence probability integral method movement and deformation system development

Thermal-mechanical coupled effect on fracture mechanism and plastic characteristics of sandstone

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Science china(Technological Sciences) 2007年第6期50卷 833-843页

作者： ZUO JianPing1,2. XIE HePing2.3, ZHOU HongWei1,2.PENG SuPing1 1 State key laboratory of Coal Resources and Safe Mining, {2. University of Mining and Technology, beijing 100083. china 2.Institute of Rock Mechanics and Fractals, {2. University of Mining and Technology, beijing 100083. china 3 Sichuan University, Chengdu 610065, {2. State key laboratory of Coal Resources and Safe Mining China University of Mining and Technology Beijing China Institute of Rock Mechanics and Fractals China University of Mining and Technology Beijing China Sichuan University Chengdu China

Scanning electronic microscopy (SEM) was employed to investigate fractographs of sandstone in mine roof strata under thermal-mechanical coupled effect. Based on the evolution of sandstone surface morphology in the failure process and frac- tography, the fracture mechanism was studied and classified under meso and mi- cro scales, respectively. The differences between fractographs under different tem- peratures were examined in detail. Under high temperature, fatigue fracture and plastic deformation occurred in the fracture surface. Therefore, the temperature was manifested by these phenomena to influence strongly on micro failure mechanism of sandstone. In addition, the failure mechanism would transit from brittle failure mechanism at low temperature to coupled brittle-ductile failure mechanism at high temperature. The variation of sandstone strength under differ- ent temperature can be attributed to the occurrence of plastic deformation, fatigue fracture, and microcracking. The fatigue striations in the fracture surfaces under high temperature may be interpreted as micro fold. And the coupled effect of tem- perature and tensile stress may be another formation mechanism of micro fold in geology.

关键词： sandstone, thermal-mechanical coupled effects, fractograph, plastic deformation, SEM, micro fold

Composition of sandstone and heavy minerals implies the provenance of Kuqa Depression in Jurassic, Tarim basin, china

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Progress in Natural Science:Materials International 2005年第7期15卷 633-640页

作者： WU Chaodong, LIN Changsong, SHEN Yanping and FENG Xue ( key laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education, Peking University, {2. 100871, china Department of Resources, china University of Geosciences, beijing 100083. china) key laboratory of Orogenic Belts and Crustal Evolution Ministry of Education Peking University Beijing 100871 China Department of Resources China University of Geosciences Beijing 100083 China

The petrological characteristics and heavy mineral assembly of the Jurassic System in Kuqa Basin are consistent with the tectonic evolution, which is the major factor controlling the filling process of Kuqa Basin. Controlled by the source areas at the both sides of the Basin, the matrixes are dominated by sedimentary rock, high-grade metamorphic rock, acid magmatic rock, and the highest heavy mineral assemblage of zircon-garnet-magnetite in the content. According to heavy mineral indexes, the Jurassic strata can be classified into three rhythmic units of heavy mineral. The lower sequence contains abundant heavy minerals and relatively high content of detritus and its matrixes primarily came form the recycling orogen. The assemblage of "zircon-garnet-magnetite" indicates that the sedimentary area in the early evolution period of the basin is relatively near the provenance. The middle sequence is different from the lower sequence in the heavy mineral assemblage and has the different characteristics from that of source rock. The heavy mineral assemblage is "garnet-zircon" with the highest content of garnet and its main matrices are the high-grade metamorphic rock, acid magmatic rock and hydrothermal vein at the northeastern edge of the basin. The middle and upper sequences are characterized by the clast provenance, which is primarily from the recycling orogen at the northern edge of the basin and secondarily from the southern uplift. As a result of the two provenances, the strata with apparent changes of heavy mineral assemblage and index better coincides with the interfaces of the secondary strata sequences, which reflects the denudation history and the filling process of the orogen at the northern edge of the basin.

关键词： sandstone components provenance analysis filling sequence tectonic evolution.

A hydrocarbon enrichment model and prediction of favorable accumulation areas in complicated superimposed basins in china

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Petroleum Science 2010年第1期7卷 10-19页

作者： Pang Xiongqi Meng Qingyang Jiang Zhenxue Liu Luofu Lu Xiuxiang State key laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China Basin and reservoir Research Center China University of Petroleum Beijing 102249 China Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

The geologic conditions of superimposed basins in china are very complicated. This is mainly shown by multi-phase structural evolution, multiple sets of source-reservoir-cap rock combinations, multiple stages of hydrocarbon generation and expulsion from source rocks, multi-cycle hydrocarbon enrichment and accumulation, and multi-phase reservoir adjustment and reconstruction. The enrichment, accumulation and distribution of hydrocarbon is mainly controlled by the source rock kitchen, paleo- anticline, regional cap rock and intensity of tectonic movement. In this paper, the T-BCMS model has been developed to predict favorable areas of hydrocarbon accumulation in complicated superimposed basins according to time and spatial relationships among five key factors. The five factors include unconformity surface representing tectonic balancing （B）, regional cap rock representing hydrocarbon protection （C）, paleo-anticline representing hydrocarbon migration and accumulation （M）, source rock kitchen representing hydrocarbon generation and expulsion （S） and geological time （T）. There are three necessary conditions to form favorable areas of hydrocarbon accumulation. First, four key factors BCMS should be strictly in the order of BCMS from top to bottom. Second, superimposition of four key factors BCMS in the same area is the most favorable for hydrocarbon accumulation. Third, vertically ordered combination and superimposition in the same area of BCMS should occur at the same geological time. The model has been used to predict the most favorable exploration areas in Ordovician in the Tarim Basin in the main hydrocarbon accumulation periods. The result shows that 95% of the discovered Ordovician hydrocarbon reservoirs are located in the predicted areas, which indicates the feasibility and reliability of the key factor matching T-BCMS model for hydrocarbon accumulation and enrichment.

关键词： Complicated superimposed basin key factor matching T-BCMS model favorable area for hydrocarbon accumulation hydrocarbon distribution prediction

Detection of the urban heat island in beijing using HJ-1B satellite imagery

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Science china Earth Sciences 2010年第S1期53卷 67-73页

作者： YANG Jun1,GONG Peng2.ZHOU JinXing3,HUANG HuaBing2.& WANG Lei2.1 key laboratory of Silviculture and Conservation,Ministry of Education,{2. Forestry University,{2. 100083.china 2.State key laboratory of Remote Sensing Science,jointly sponsored by the Institute of Remote Sensing Applications,Chinese Academy of Sciences and {2. Normal University,{2. 100101,china 3 Institute of Desertification Studies,Chinese Academy of Forestry,{2. 100091 china key laboratory of Silviculture and Conservation Ministry of Education Beijing Forestry University Beijing China State key laboratory of Remote Sensing Science jointly sponsored by the Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Beijing China Institute of Desertification Studies Chinese Academy of Forestry Beijing China

Satellite images are used extensively in studying the urban heat island(UHI) *** evaluated the suitability of thermal infrared(TIR) data from the HJ-1B satellite for detecting UHI using a case study in *** modified algorithms for retrieving the land surface temperature(LST) from HJ-1B data were *** results were compared with LST images derived from a Landsat TM thermal band and the MODIS LST *** spatial pattern of UHI generated using HJ-1B data matched well with that produced using TM and MODIS *** the two algorithms,the mono-window algorithm performed better but further tests are *** more frequent coverage than TM and higher spatial resolution than MODIS,the HJ-1B TIR data present a unique opportunity to study thermal environments in cities in china and neighboring countries.

关键词： surface temperature NDVI mono-window algorithm single-channel algorithm