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SPONTANEOUS POLARIZATION AND THE DISTRIBUTION OF INTERNAL STRESS AND ELECTRIC FIELDS AROUND A TRIPLE POINT

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Acta Mechanica Solida Sinica 2000年第1期13卷 1-8页

作者： zhang Ying (Department of Materials Science,xiamen university,xiamen 361005,china) xiamen Univ Dept Mat Sci Xiamen 361005 Peoples R China

In this article, distributions of internal stress and internal electric fields around a triple point of ferroelectric polycrystals generated by the spontaneous deformation and spontaneous polarization were investigated. It was found that when all three grains consist of a single domain, the internal stresses and the internal electric fields do not vanish. Though it may be determined according to the principle of energy, the spontaneous configuration will not be unique without involving other conditions due to the symmetry of the crystal structure.

关键词： spontaneous polarization internal stress internal electric field electric domain

Reduced-glutathione concentrations in Boleophthalmus pectinirostris tissues exposed to benzo(a)pyrene

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Journal of Environmental Sciences 2001年第3期13卷 308-310页

作者： FENG Tao 1, ZHENG Wei yun 1, GUO Xiang\|qun\+2, zhang Yong\+1(1.Environmental Science Research Center, xiamen university, xiamen 361005, china 2.Chemistry Department, xiamen university, xiamen\ 361005, china) Environmental Science Research Center Xiamen University Xiamen 361005 China.

The concentrations of reduced-glutathione ( GSH) in liver and ovary of Boleophthalmus pectinirostris are quantified. The concentrations of GSH in the ovary are much higher than that of GSH in the liver(nearly 3 times of the liver). The study also investigates the changes of GSH contents in the two organs while the fishes were exposed to benzo(a)pyrene(BaP) at concentrations of 0, 0.05, 0.2 and 0.5 mg/L respectively for up to a week. The concentrations of GSH in the liver of BaP-exposed fish increased significantly with dose, whereas the concentrations of GSH in the ovary decreased significantly compared to controls. The results suggested that both the liver and the ovary are the primary organ in BaP metabolism, and that the changes of GSH levels may represent an adaptive response or toxic effect to Bap exposure.

关键词： Boleophthalmus pectinirostris benzo(a)pyrene reduced-glutathione

Every Banach space with a w*-separable dual hasa 1+ε-equivalent norm with the ball covering property

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Science china Mathematics 2009年第9期52卷 1869-1874页

作者： CHENG Lixin, SHI HuiHua & zhang Wen School of Mathematical Sciences, xiamen university, xiamen 361005, china School of Mathematical Sciences Xiamen University Xiamen China

A normed space is said to have ball-covering property if its unit sphere can be contained in the union of countably many open balls off the origin. This paper shows that for every ε>0 every Banach space with a w*-sep... 详细信息

关键词： ball-covering property renorming Banach space

Interatomic Potentials for NiZr Alloys from Experimental and Ab initio Calculations

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Chemical Research in Chinese Universities 2002年第1期18卷 38-41页

作者： TAN Kai, LIN Meng-hai , WANG Nan-qin and zhang Qian-er Department of Chemistry,xiamen university,xiamen 361005,P.R.china xiamen Univ Dept Chem Xiamen 361005 Peoples R China

We applied an approach to the development of many-body interatomic potentials for NiZr alloys,gaining an improved accuracy and *** functional form of the potential is that of the embedded method,but it has been improved as follows. (1) The database used for the development of the potential includes both experimental data and a large set of energies of different structures of the alloys generated by Fab initio calculations. (2) The optimum parametrization of the potential for the given database is obtained by fitting. Using this approach we developed reliable interatomic potentials for Ni and Zr. The potential accurately reproduces basic equilibrium properties of the alloys.

关键词： Ab initio NiZr alloy Many-body interatomic potential

Structures and stability of (HAlNH)_n(n=1-15)

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Chinese Science Bulletin 2001年第18期46卷 1507-1514页

作者： WU Haishun, zhang Congjie, XU Xiaohong, zhang Fuqiang & zhang QianerDepartment of Chemistry, Shanxi Normal university, Linfen 041004, china Department of Chemistry, xiamen university, xiamen 361005, china Department of Chemistry Shanxi Normal University Linfen China Department of Chemistry Xiamen University Xiamen China

The geometries, electronic states, vibrational spectra and thermodynamic properties for (HAINH)n clusters with n=1-15 have been investigated using the ab initio DFT/B3LYP method with basis sets 6-31G* and their ground state structures obtained. Comparison of the (HAINH)n with (A1N)n clusters shows that the skeletons of (HAINH)n consist of four-membered and six-membered rings made of Al-N bonds, and either Al or N atom forms four bonds in which three ones are Al-N bonds and the rest is Al-H or N-H bond. The number of Al-N bonds of (HAINH)n is equal to that of (AlN)n. The magic number regularity of (HAINH)n is n =2, 4, 6, 8, etc., all of which are even numbers.

关键词： DFT method (HAINH)n cluster structure stability.

Formation and Photoelectrochemical Properties of Charge Transfer Complexes between Fullerene and Metallophthalocyanine

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Chinese Chemical Letters 1999年第9期10卷 745-748页

作者： Zai Hong CHEN Jun LIN Juan LI Hui zhang(Department of Chemistry, xiamen university, xiamen 361005) xiamen Univ Dept Chem Xiamen 361005 Peoples R China

The formation of charge transfer complexes (CTC) between C-60 with metallophthalocyanine (MPc. M=Zn, Co) has been investigated in three mixed organic solvents. The MPc-C-60 CTC were characterized by using UV-Vis and fluorescence spectra. The formation equilibrium constants (K) of CTC and their stoichiometry were determined. The foundation of CTC leads to a remarkable enhancement of the photoelectrochemical property. The CTC will provide a potential opportunity to develop a new applicable photoelectric material.

关键词： C-60 metalllophthalocyanine photoelectrochemical property

Identification of human microRNA-disease association via low-rank approximation-based link propagation and multiple kernel learning

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Frontiers of Computer Science 2024年第2期18卷 217-229页

作者： Yizheng WANG xin zhang Ying JU Qing LIU Quan ZOU Yazhou zhang Yijie DING Ying zhang Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Yangtze Delta Region Institute(Quzhou) University of Electronic Science and Technology of ChinaQuzhou 324000China Beidahuang Industry Group General Hospital Harbin 150088China School of Informatics Xiamen UniversityXiamen 361005China Department of Anesthesiology Hospital(T.C.M)Affiliated to Southwest Medical UniversityLuzhou 646000China Software Engineering College Zhengzhou University of Light IndustryZhengzhou 450002China

Numerous studies have demonstrated that human microRNAs(miRNAs)and diseases are associated and studies on the microRNA-disease association(MDA)have been *** developed a model using a low-rank approximation-based link propagation algorithm with Hilbert–Schmidt independence criterion-based multiple kernel learning(HSIC-MKL)to solve the problem of the large time commitment and cost of traditional biological experiments involving miRNAs and diseases,and improve the model *** constructed three kernels in miRNA and disease space and conducted kernel fusion using *** propagation uses matrix factorization and matrix approximation to effectively reduce computation and time *** results of the experiment show that the approach we proposed has a good effect,and,in some respects,exceeds what existing models can do.

关键词： human miRNA-disease association multiple kernel learning link propagation miRNA similarity disease similarity

Disequilibria between ^(210)Po and ^(210)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 Yusheng1,2 1. Department of Oceanography, xiamen university, xiamen 361005, china 2. State Key Laboratory of Marine Environmental Science, xiamen university, xiamen 361005, 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, ^(210)Pb and ^(210)Po,were measured in both dissolved ( 0.45 μm) phases from surfacewaters of the southern South china Sea. The average activity of particulate ^(210)Pb, 0.23 Bq/m^3 (n= 23), accounted for about 12% of the total ^(210)Pb, which corresponds with values of open *** ^(210)Po, with an average activity of 0.43 Bq/m^3, accounted for about 40% of the total^(210)Po, which was much higher than those of open and eutrophic oceans. The residence times oftotal ^(210)Po and ^(210)Pb in surface waters estimated from an irreversible steady-state model were0.82 a and 1.16 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 ^(210)Po and ^(210)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^(210)Po and ^(210)Pb in different marine environments: in eutrophic ocean, plankton detritus andfecal pellets are the main carrier of ^(210)Po and ^(210)Pb, by which ^(210)Po and ^(210)Pb havebeen scavenged and removed; while in oligotrophic ocean, microbes could become the main carrier of^(210)Po and fractionate ^(210)Po and ^(210)Pb significantly as a result of scarce plankton detritusand fecal pellets. These results suggest the use of ^(210)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, 210Po, 210Pb, disequilibria, scavenging.

Analysis of sea surface temperature fronts in the Taiwan Strait and its adjacent area using an advanced edge detection method

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Science china Earth Sciences 2010年第7期53卷 1008-1016页

作者： PI QingLing1,2,3 & HU JianYu1,2 1 State Key Laboratory of Marine Environmental Science, xiamen university, xiamen 361005, china 2 Department of Oceanography, xiamen university, xiamen 361005, china 3 china Communications Construction Company First Harbor Consultants CO., LTD., Tianjin 300222, china 1. State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China2. Department of Oceanography Xiamen University Xiamen 361005 China3. China Communications Construction Company First Harbor Consultants CO. LTD. Tianjin 300222 China

A morphology-based edge detection method has been used to study sea surface temperature (SST) fronts in the Taiwan Strait and its adjacent area. The method is based on mathematical morphology with multi-dimensional and multi-structural elements. Using six years’ SST data from September 2002 to August 2008, we distinguished the large SST front like Kuroshio Front as well as the smaller ones: namely Taiwan Bank Front, Zhe-Min Coastal Front and zhang-Yun Ridge Front. The seasonal and monthly variations of these fronts were also studied. Generally, the SST fronts are stronger in winter but weaker in summer. And the fronts are at their active stage during the period from January to May but at their declining stage during the period from July to October.

关键词： SST front remote sensing edge detection Taiwan Strait Kuroshio