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Journal of Wuhan university of Technology(Materials Science) 2007年第1期22卷 168-170页

作者：任平 Energy Source and Environmental Engineering department Shanghai University of Electric Power

Hollow spheres of hexagonal ferrite BaCozFelrO27 were fabricated through a spray pyrolysis technique using co-precipitation ferrite powder precursor as materials, followed by calcinations in an air atmosphere. The phase composition, micro-morphology, and static magnetic property of the particles were measured by XRD, SEM, and VSM. The results indicate that the method for preparation of ferrite hollow microspheres （FHM） results in a broad particles size distribution. The density of FHM decreased from 5.31.g/ cm^3 to 2.31.g/cm^3. When the heating rate was 5℃/min, and temperature was 1.200℃ for 4 hours, pure W-type ferrites were formed. With the heat treatment temperature and time increasing, the crystal structure becomes perfect, the saturation magnetization is increased and the coercive force is decreased.

关键词： microwave absorber ferrite hollow microspheres spray pyrolysis

Technique for image fusion based on non-subsampled contourlet transform domain improved NMF

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Science China(Information Sciences) 2010年第12期53卷 2429-2440页

作者： KONG WeiWei1,LEI YingJie1,LEI Yang1 & zhang Jie2.1.1} of Computer Engineering,Missile Institute,Air Force Engineering university,Xi'an 713800,China 2.1. of Computer,Qinghai university,Xining 810016,China 1. department of Computer Engineering Missile Institute Air Force Engineering University Xi’an 713800 China2. Department of Computer Qinghai University Xining 810016 China

To overcome the problem of multi-sensor image fusion,a technique for image fusion based on non-subsampled contourlet transform(NSCT) domain improved nonnegative matrix factorization(NMF) is ***,by using NSCT,multi-scale and multi-direction sparse decompositions of source images are ***,an improved NMF technique is utilized to complete the fusion of low-frequency *** low-frequency fused image can be produced fast by the process which does not involve the randomization of the vectors W and H at all,in addition,the fusion course of high-frequency sub-images can be dealt with by use of the model of adaptive unit-fast-linking pulse coupled neural network(AUFLPCNN).Finally,the ultimate fused image can be obtained by synthesizing all sub-images with inverse *** simulated experiments show that the technique is effective.

关键词： image fusion non-subsampled contourlet transform nonnegative matrix factorization singular value decomposition

Application of ensemble kalman filter to geophysical parameters retrieval in remote sensing:A case study of kernel-driven BRDF model inversion

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Science China Earth Sciences 2006年第6期49卷 632-640页

作者： QIN Jun1. YAN Guangjian1. LIU Shaomin1. LIANG Shunlin2, zhang Hao1. WANG Jindi1.& LI Xiaowen1.1. State Key Laboratory of Remote Sensing Science, School of Geography and Remote Sensing, Research Center for RS&GIS, Beijing Normal {1., Beijing 1.0875, China 2. department of Geography, 21.1.Lefrak Hall, {1. of Maryland, College Park, MD20742, USA 1. State Key Laboratory of Remote Sensing Science School of Geography and Remote Sensing Research Center for RS&GIS Beijing Normal University Beijing 100875 China 2. department of Geography 2181 Lefrak Hall University of Maryland College Park MD20742 USA

The use of a priori knowledge in remote sensing inversion has great implications for ensuring the stability of inversion process and reducing uncertainties in retrieved results, especially under the condition of insufficient observations. Common optimization algorithms have difficulties in providing posterior distribution and thus cannot directly acquire uncertainties in inversion results, which is of no benefit to remote sensing application. In this article, ensemble Kalman filter (EnKF) has been introduced to retrieve surface geophysical parameters from remote sensing observations, which has the capability of not merely obtaining inversion results but also giving its posterior distribution. To show the advantage of EnKF, it is compared to standard MODIS AMBRALS algorithm and highly effi-cient global optimization method SCE-UA. The inversion abilities of kernel-driven BRDF models with different kernel combinations at several main cover types are emphatically discussed when observa-tions are deficient and a priori knowledge is introduced into inversion.

关键词： remote sensing inversion, a priori knowledge, posterior distribution, ensemble kalman filter, BRDF, kernel-driven model, albedo.

Early J_2 basalts in SE China:Incipience of large-scale late Mesozoic magmatism

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Science China Earth Sciences 2006年第8期49卷 796-815页

作者： XIE Xin1. XU Xisheng1. ZOU Haibo2, JIANG Shaoyong1. zhang Ming3 & QIU Jiansheng1.1. State Key Laboratory of Mineral Deposit Research, {1. of Earth Sciences, Nanjing university, Nanjing 21.093, China 2. {1. of Earth and Space Sciences, university of California at Los Angeles, Los Angeles, CA90095-1.67, USA. 3. GEMOC ARC National Key Centre, {1. of Earth and Planetary Sciences, Macquarie university, Sydney, N.S.W. 21.9, Australia 1. State Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China 2. department of Earth and Space Sciences University of California at Los Angeles Los Angeles CA90095-1567 USA 3. GEMOC ARC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney N.S.W. 2109 Australia

Magmatism in SE China was dormant during 204―1.0 Ma, but was reactivated in 1.0― 1.0 Ma (early J2), and then became more and more intensive towards the end of early Cretaceous. The small-scale early J2 magmatism is the incipience to long-term and large-scale magmatism in this region. A near east-west (EW) trend volcanic belt was distributed across south Hunan, south Jiangxi and southwest Fujian was formed during early J2 time. Along this belt from the inland toward the coast, the lithology of basalts changes from alkali into tholeiite, and the amount of erupted volcanic rocks and the proportions of rhyolites coexisting with the basalts increase. On the basis of geochemical char- acteristics of these basalts, we infer that the melting degree of source rocks and the extent of frac- tional crystallization and crustal contamination all increased whereas the depth of mantle source de- creased from the inland to the coast, which led to the variations of geological characteristics of the volcanic belt. In early J2, the western spreading Pacific plate began to subduct underneath SE China continental block, reactivating near EW trend deep fault that was originally formed during the Indos- inian event. The stress of the western spreading Pacific plate and the extent of asthenosphere up- welling increased from the inland to the coast, which is consistent with the generation and evolution of early J2 basalts.

关键词： early J2 basalts, upwelling of asthenosphere, large-scale magmatism, SE China, the Pacific plate.

Effect of bond length and radius on superconducting transition temperature for FeAs-based superconductors

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Science China(Physics,Mechanics & Astronomy) 2010年第1期53卷 59-63页

作者： CHEN Ning 1., LIU Yang 1., JIA YaKui 1., QU ShaoPeng 1., zhang WanJie 1.& LI Yang {1.School of Material Science and Engineering, university of Science and Technology Beijing, Beijing 1.0083, China 2 department of Engineering Science and Materials, university of Puerto Rico at Mayaguez, Mayaguez PR 00681.9044, USA 1. School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China2. Department of Engineering Science and Materials University of Puerto Rico at Mayaguez Mayaguez PR 00681-9044 USA

By comparing the data of lattice parameters of more than 50 new FeAs-based high temperature superconductors in two syetems, the effect of bondlength on superconducting transition temperature (T C ) was found that, for both FeAs superconductor systems with similar ionic radii of cation A, the bond length L As-A between Arsenic atom and its nearest neighbor cation at the A site is in an inverse proportion to T C , i.e. the larger the bond length L As-A , the lower the T C . In addition, we also found a noticeable effect of ionic radius on T C , in which deviation from the tendency line of bond length vs. T C decreases with the increasing ionic radius. Both bond length-T C and ionic radii-T C relations indicate that the interaction of cation A and As ion have significant effect on superconductivity. The analysis on the electronic structure indicates that there exists the proximity of the secondary-outer p-orbit of the cation A and the 4s orbit of the As ion, both in energy space and in real space. Some high frequency individual vibrating modes would be established through exchange coupling on their inner orbits. It is worth of mention that the superconducting condensation is influenced by the interaction between the cation A and the As atoms.

关键词： lattice constant FeAs-based superconductor superconducting transition temperature

Database of open-framework aluminophosphate syntheses:introduction and application(Ⅰ)

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Science China Chemistry 2009年第11期52卷 1734-1738页

作者： YAN Yan1.LI JiYang1.QI Miao2,zhang Xiao1.YU JiHong1.& XU RuRen1.1.State Key Laboratory of Inorganic Synthesis and Preparative Chemistry,Jilin {1.,Changchun 1.2}1.,China 2 department of Chemistry,Northeast Normal {1.,Changchun 1.01.7,China 1. State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130012 China 2. department of Chemistry Northeast Normal University Changchun 130117 China

The database of open-framework aluminophosphate(AlPO) syntheses has been established,which includes about 1.00 synthetic *** analysis has been done on the basis of the framework composition,structure dimension,pore ring,and organic *** database will serve as useful guidance for the rational synthesis of microporous functional materials.

关键词： aluminophosphates open framework synthesis database

Stochastic bi-resonance induced by external noise for Ca^2+ signaling in hepatocytes

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Science China Chemistry 2005年第4期48卷 286-291页

作者： zhang Jiqian1.2,HOU Zhonghuai1.& XIN Houwen1.1.{1. of Chemical Physics,university of Science and Technology of China,Hefei 230026,China 2.College of Physics and Electronic Information,Anhui Normal university,Wuhu 2.1.00,China 1. department of Chemical Physics University of Science and Technology of China 230026 Hefei China 2. College of Physics and Electronic Information Anhui Normal University 241000 Wuhu China

The influence of external noise on intracellular Ca2+ oscillations dynamics in a single cell of rat hepatocytes is *** coherence of noise-induced intracellular Ca2+ oscillations reached two maxima for multiple external noise intensity,indicating the occurrence of external noise stochastic bi-resonance (SBR).This phenomenon is compared with our previous result that was induced by internal ***,the deterministic bifurcation character of the system was also discussed.

关键词： stochastic bi-resonance, environment fluctuation, calcium oscillations.

Quantum statistical entropy corresponding to cosmic horizon in five-dimensional spacetime

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Science China(Physics,Mechanics & Astronomy) 2008年第2期51卷 140-146页

作者： ZHAO Ren1.2 & zhang ShengLi1.1.{1. of Applied Physics, Xi’an Jiaotong university, Xi’an 71.049, China 2 {1. of Physics, Shanxi Datong university, Datong 037009, China department of Applied Physics Xi’an Jiaotong University Xi’an 710049 China department of Physics Shanxi Datong University Datong 037009 China

The generalized uncertainty relation is introduced to calculate the quantum statis-tical entropy corresponding to cosmic horizon. By using the new equation of state density motivated by the generalized uncertainty relation, we discuss entropies of Bose field and Fermi field on the background of five-dimensional spacetime. In our calculation, we need not introduce cutoff. There is no divergent logarithmic term in the original brick-wall method. And it is obtained that the quantum statistical en-tropy corresponding to cosmic horizon is proportional to the area of the horizon. Further it is shown that the entropy corresponding to cosmic horizon is the entropy of quantum state on the surface of horizon. The black hole's entropy is the intrinsic property of the black hole. The entropy is a quantum effect. In our calculation, by using the quantum statistical method, we obtain the partition function of Bose field and Fermi field on the background of five-dimensional spacetime. We provide a way to study the quantum statistical entropy corresponding to cosmic horizon in the higher-dimensional spacetime.

关键词： quantum statistical entropy generalized uncertainty relation high-dimensional spacetime

Investigation on extremal and critical characteristics of ignition time for H_2/O_2 combustion system and their applications

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Science China(Technological Sciences) 2009年第5期52卷 1161-1166页

作者： CHEN JianHua1.zhang HuiQiang2,LI ZhuoYi2 & zhang GuiTian1.1.School of Aerospace,North Western Polytechnical university,Xi’an 71.072,China 2 department of Engineering Mechanics,Tsinghua university,Beijing 1.0084,China School of Aerospace North Western Polytechnical University Xi’an 710072 China department of Engineering Mechanics Tsinghua University Beijing 100084 China

The L,H and C curves in P-T phase are proposed to describe the minimal,maximal and critical char-acteristics of ignition time of H2/O2 combustion system,*** features of H2/O2(Air) com-bustion system,including explosion or not as well as the time delay to achieve its explosion status,can be well shown by explosion limits and these proposed *** curves can be described by 1.2.1.ks[Ms],(k1./k1.+1.k1.ks[Ms],and 2.1.ks[Ms],respectively,which provide a physical explanation for these curves and give another way to establish *** on the contour of ignition time,the Z-type explosion limits can be explained by thermal explosion ***,the ignition distance of supersonic combustion is predicted according to the ignition time obtained in a Semenov system,which is very reasonable.

关键词： ignition time thermal explosion detailed reaction mechanism Semenov system supersonic combustion

Disequilibria between ^(21.)Po and ^(21.)Pb in surface waters of the southern South China Sea and their implications

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Science China Earth Sciences 2006年第1期49卷 103-112页

作者： YANG Weifeng, HUANG Yipu1.2, CHEN Min1.2, zhang Lei, LI Hongbin, LIU Guangshan1.2 & QIU Yusheng1.{1. department of Oceanography, Xiamen university, Xiamen 361.05, China 2. State Key Laboratory of Marine Environmental Science, Xiamen university, Xiamen 361.05, China 1. department of Oceanography Xiamen University Xiamen 361005 China 2. State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

Activities of the naturally occurring radionuclides, ^(21.)Pb and ^(21.)Po,were measured in both dissolved ( 0.45 μm) phases from surfacewaters of the southern South China Sea. The average activity of particulate ^(21.)Pb, 0.23 Bq/m^3 (n= 23), accounted for about 1.% of the total ^(21.)Pb, which corresponds with values of open *** ^(21.)Po, with an average activity of 0.43 Bq/m^3, accounted for about 40% of the total^(21.)Po, which was much higher than those of open and eutrophic oceans. The residence times oftotal ^(21.)Po and ^(21.)Pb in surface waters estimated from an irreversible steady-state model were0.82 a and 1.1. a, respectively. The consistently high fractionation factor calculated either byscavenging rate constants (5.42) or K_d values (6.69) suggested that a significant fractionationoccurred between ^(21.)Po and ^(21.)Pb during their removal from solution to particles and that thetwo radionuclides had different biogeochemical cycling pathways in the oligotrophic South China ***, our results indicated that there exist different fractionation mechanisms between^(21.)Po and ^(21.)Pb in different marine environments: in eutrophic ocean, plankton detritus andfecal pellets are the main carrier of ^(21.)Po and ^(21.)Pb, by which ^(21.)Po and ^(21.)Pb havebeen scavenged and removed; while in oligotrophic ocean, microbes could become the main carrier of^(21.)Po and fractionate ^(21.)Po and ^(21.)Pb significantly as a result of scarce plankton detritusand fecal pellets. These results suggest the use of ^(21.)Po to trace marine biogeochemicalprocesses relating to microbial activities and the cycling of sulfur group elements (S, Se, Te andPo).

关键词： South China Sea, 21.Po, 21.Pb, disequilibria, scavenging.