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Multi-isotopic system geochronology of low temperature eclogite from Huangzhen,Southern Dabie Terrain

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Science China earth Sciences 2004年第10期47卷 931-942页

作者： CHeN Daogong1. e. Deloule2, CHeNG Hao1. XIA Qunke1.& WU Yuanbao1.1. School of earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China 2. CRPG-CNRS Nancy, 54501. France 1. School of earth and Space Sciences University of Science and Technology of China 230026 Hefei China 2. CRPG-CNRS 54501 Nancy France

Zircon U-Pb thermal ionization mass-spectrometer (TIMS) and secondary ion mass-spectrometer (SIMS) dating, mica and amphibole 40Ar-39Ar dating and mineral Sm-Nd isotopic compositions of Huangzhen low temperature eclogite and country granitic gneiss are carried out. The zircon U-Pb weighted average SIMS age is (231.6?9.7) Ma for one eclogite. The mica 40Ar-39Ar isochron age is (232.6?2.1. Ma and the lowest plateau age is (221.7?2.4) Ma from same sample. U-Pb TIMS concordant ages from other eclogite zircons are from (221.3?1.4) Ma to (222.5?2.3) Ma. U-Pb SIMS low intercept age from country granitic gneiss is (221.35) Ma. The retrograde amphibole 40Ar-39Ar isochron age is (205.9?1.0) Ma. except for mica, which may contain excess 40Ar, all the ages represent peak and retrograde metamorphism of low temperature eclogites. It is indicated that the Huangzhen low temperature eclogites differ from Xiongdian low temperature eclogites of north of the Northern Dabie Terrain in metamorphic ages. Huangzhen low temperature eclogites share one coherent HP-UHP terrain with high temperature eclogites from Southern Dabie Terrain and they may have differences in subduction depth and cooling rates during exhumation.

关键词： low temperature eclogite, multi-isotopic dating, HP-UHP metamorphism, Dabieshan.

electronic structure and magnetic properties of metastable SmCo_(7) compound

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 325-335页

作者： ZHANG Changwen 1., LI Hua 1., DONG Jianmin 1., WANG Yongjuan 1., PAN Fengchun 1., ZHANG Jian 1., GUO Yongquan 2 & LI Wei 2 1. School of Physics and Microelectronics, Shandong University, Jinan 2501.0, China 2. Institute of Functional Materials, Central Iron and Steel Research Institute, Beijing 1.0081. China 1. School of Physics and Microelectronics Shandong University 250100 Jinan China 2. Institute of Functional Materials Central Iron and Steel Research Institutes 100081 Beijing China

The electronic density of states, spin-splittings and atomic magnetic moments of SmCo 7 compound have been studied using spin-polarized MS-Xα method. The results show that a few of electrons are transferred to Sm(5d 0 ) orbital because of orbital hybridization between Sm and Co atoms in the compound. The exchange interactions between 3d and 5d electrons lead to the magnetic coupling between Sm and Co, and therefore, result in the long-range ferromagnetic order inside the SmCo 7 compound. There are negative exchange couplings occurring at some levels, which weakens the strength of average coupling around Co lattice. So, the Curie temperature and Co-moment of SmCo 7 decrease distinctly compared with pure Co. Compared with SmCo 5 compound, the disordered substitution of Co-Co “dumbbell-atom” pairs for Sm changes the local environment of Co lattice, which makes the 2e site bear negative magnetic moment. The strength of hybridization near Fermi level weakens and the free energy of the compound increases obviously. Thus, SmCo 7 is a metastable compound at room temperature. Considering the localization of 4f electrons and a few of 5d electrons arising from the orbital hybridization, the magnetic moment of Sm atom will be 1.61. B in SmCo 7 compound, which is in agreement with the experimental values of Sm 3+ ion- moment and Sm atom-moment in metals.

关键词： electronic structure, spin polarization, atomic magnetic moment, exchange coupling, Curie temperature.

Parentage determination of an isolated Yangtze finless porpoise population Neophocaena phocaenoides asiaeorientalis in the Yangtze Tian-e-Zhou Baiji National Natural Reserve based on molecular data

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Progress in Natural Science:Materials International 2005年第2期15卷 54-61页

作者： XIA Junhong 1.2, ZHeNG Jinsong 1.2, XU Limei 1.2 and WANG Ding1.(1. Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China 2. Graduate School of the Chinese Academy of Sciences, Beijing 1.0039, China) Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Reproductive behaviors are poorly known for the Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis. In this study, the parentage of an isolated Yangtze finless porpoise population inhabiting the Yangtze Tian-e-Zhou Baiji National Natural Reserve is determined by analysis of microsatellite loci and mitochondrial DNA (mtDNA) control region sequences, and the porpoise's reproductive behaviors are studied. Overall 4 full parentage assignments and additional 3 single parentage assignments were determined for the population of 23 individuals. The analysis shows that their estimated reproductive cycle is shorter than that reported previously and there probably exists an overlapping between gestation and lactation period. The study also shows that the female does not show fidelity to a particular male for breeding and vice versa, the oldest males did not monopolize mating and the dominance rank could not be so strict for the porpoise society. Moreover, the porpoise's mating pattern and relatedness among candidate parents are discussed here. These results provide important information for making guidelines of management and conservation for this protected population.

关键词： Yangtze finless porpoise isolated population reproductive behavior parentage

Distribution of actinomycetes in oil contaminated ultisols of the Niger Delta(Nigeria)

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Journal of environmental Sciences 2000年第3期12卷 296-302页

作者： J.P. essien 1. e. D. Udosen 2 (1. Department of Microbiology, University of Uyo, Nigeria 2. Department of Chemistry and Biochemistry, University of Uyo,Nigeria) Department of Microbiology University of Uyo Nigeria Department of Chemistry and Biochemistry University of Uyo Nigeria

The distribution of actinomycetes in oil contaminated sandy loam ultisols of the Niger Delta region of Nigeria was studied to aid in understanding the effect of hydrocarbons on indigenous microbial population in tropical soils. The average total counts of actinomycetes in all the oil samples analysed was 1. 3 cfu/g. Higher counts of actinomycetes were observed during the dry season than during the wet season. The counts of hydrocarbonoclastic actinomycetes correlated positively with the total count of actinomycetes. The actinomycetes were generally restricted to the top soil(0—1. cm soil depth) although a seemingly deeper(down to 40 cm soil depth) distribution was noticed in the dry season. The isolates included oil degrading species of Actinoplanes, Norcadia, Streptomyces and Streptosporangium. Their high oil utilization ability indicates their positive potential and role in the bioremediation of oil spilled soils.

关键词： actinomycetes oil contaminated ultisols

Four kinds of eNU-induced white spot mice and chromosome locations of the mutant genes

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Chinese Science Bulletin 2003年第24期48卷 2658-2664页

作者： WU Baojin1.2, MAO Huihua1. SHAO Yixiang1. XUe Zhengfeng1.& LI Houda1.1. Comparative Medicine Center of Yangzhou University, Yangzhou 225009, China 2. Medical College of Yangzhou University, Yangzhou 225001. China Correspondence should be addressed to Li Houda (e-mail: houdali @***) Comparative Medicine Center of Yangzhou University China Medical College of Yangzhou University China

Phenotype-driven is the name for an ap-proach used to study gene functions through mutagenesis, location and cloning of the mutant gene. In this study, 1.0 male C57BL/6J(B6) mice were treated with eNU and repro-duced a total offspring of 3860. Of these descendants, 21. exhibited mutation phenotypes by screening, and more than 1. of them are hereditable. Four kinds of mutant mice, named Wbct, W-1.ao, W-2Bao, and W-3Bao, showed dominant hereditary white spot mutation with partial albinism on their belly, distal limbs and tail terminal. To map these mutant genes, 39 microsatellites, equally distributed on the mouse genome and with difference between B6 and DBA/2J (D2), were selected to scan the genome after discrimination of the white spots in the F2 mice [(B6×D2)×D2]. It is found that, the log odds score (LODS) between W-1.ao and D5Mit1.8 is 0.56, and the LODS of W-1.ao and D5Mit352 is 4.47. With the gradual application of microsatellites D5Mit290, D5Mit31., D5Mit308 and D5Mit356 that are close to the mutant gene, and the number of F2 mice going up to 537, the mutant W-1.ao is located between D5Mit356 and D5Mit308 on chro-mosome 5, about 42.1. cM from the centromere. In the same way, W-2Bao and W-3Bao are mapped nearby W-1.ao, and Wbct is located on chromosome 1. about 41.6 cM from the centro-mere. After searching for the mouse genome database (MGD) and performing a one-by-one study of all genes located on chromosome subregion, it is believed that the kit gene is an excellent candidate for the white spot mutations of W-1.ao, W-2Bao and W-3Bao.

关键词：染色体突变基因基因工程 eNU

experimental determination of interfacial energies for Ag_2Al solid solution in the CuAl_2-Ag_2Al system

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Chinese Physics B 2009年第9期18卷 3952-3959页

作者： Ocak Y Akbulut S Keslioglu K Marasl1.N ad1.l1.e Kaya H Department of Physics Faculty of Arts and SciencesErciyes University Department of Physics Institute of Science and TechnologyErciyes University Department of Physics Faculty of Arts and SciencesNigde University Department of Science education Education FacultyErciyes University

The equilibrated grain boundary groove shapes of solid solution Ag2Al in equilibrium with an AI-Cu-Ag liquid were observed from a quenched sample with a radial heat flow apparatus. The Gibbs Thomson coefficient, solid liquid interfacial energy and grain boundary energy of the solid solution Ag2Al have been determined from the observed grain boundary groove shapes. The thermal conductivity of the solid phase and the thermal conductivity ratio of the liquid phase to solid phase for Ag2Al-28.3 at the %CuAl2 alloy at the melting temperature have also been measured with a radial heat flow apparatus and Bridgman type growth apparatus, separately.

关键词： solid-liquid interfaces metals and alloys surface energy thermal conductivity

N_2O emissions from agricultural soils in the North China Plain: the effect of chemical nitrogen fertilizer and organic manure

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Journal of environmental Sciences 2000年第4期12卷 463-468页

作者： DONG Yun\|she 1.2,3 , Dieter Scharffe 2, Manfred Domroes 3, QI Yu chun 1. ZHANG Shen 1.(1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 1.01.1. China e\|mail: dongys@*** 2. M 中科院地理科学与资源所北京 1 0 0 1 0 Max- Planck-Institute of Chemistry 德国 Mainz 550 2 0 Mainz University 德国 Mainz 550 99

An enclosed chamber technique was used to measure N 2O emissions from intensively agricultural soils of the North China Plain during the periods of 1.95—1.96 and 1.97—1.98, to reflect distinct components of winter wheat and summer maize growing seasons. The results showed that the continuous application of fertilizer in agricultural soils increased N\-2O emissions by a factor of 24.1.28.1. the calculated annual chemical N fertilizer\|transformed N\-2O\|N emissions was 0.67%. Our results indicated that the application of organic manure also had a significant influence on soil N 2O emissions, which combined with the use of chemical N increased about 20% in a year. It was calculated that there were about 0.1.% N of organic manure transformed as N 2O N. Annual mean N 2O emission from our study area of fertilized soils was estimated to be 57.1.μgN 2O/(m 2·h). A weak correlation was also found between N 2O emissions and soil available nitrogen content NH + 4.

关键词： N_2O emissions the North China Plain agricultural soils chemical nitrogen organic manure

Molecular dynamics simulation of mechanical properties of TATB/fluorine-polymer PBXs along different surfaces

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Science China Chemistry 2005年第6期48卷 504-510页

作者： XIAO Jijun1. HUANG Yucheng1. HU Yingjie1.2 & XIAO Heming1.1. Department of Chemistry, Nanjing University of Science and Technology, Nanjing 21.094, China 2. Department of Chemistry, Nanjing Xiaozhuang College, Nanjing 21.01., China Correspondence should be addressed to Xiao Heming (email: xiao@***) 1. Department of Chemistry Nanjing University of Science and Technology 210094 Nanjing China 2. Department of Chemistry Nanjing Xiaozhuang College 210017 Nanjing China

The mechanical properties of PBXs composed of the well-known insensitive explo-sive TATB (1.3,5-Triamino-2,4,6-trinitrobenzene) crystal and four kinds of typical fluo-rine-polymers, i.e. poly (vinylidene difluoride) (PVDF), polychlorotrifluoroethylene (PCTFe), fluo-rine rubber (F231.) and fluorine resin (F231.) individually, have been simulated by molecular dy-namics (MD) method. The results show that the mechanical properties of TATB can be effectively improved by blending with a small amount of fluorine-polymers. Different mechanical properties of PBXs are obtained by putting fluorine-polymer binders parallel to different crystalline surfaces. The whole effect of improving mechanical properties is found to be (01.)?(1.0)>(001..

关键词： TATB, polymer bonded explosives, mechanical properties, molecular dynamics.

A maximum entropy distribution for wave heights of non-linear sea waves

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Progress in Natural Science:Materials International 2007年第11期17卷 1318-1326页

作者： Zhou Liangming1. Xu Delun1. Wang Aifang1. Chen Zhengshou2 and Yan Xiuhua1.1. Physical Oceanography Laboratory, Ocean University of China, Qingdao 2661.0,China 2.engineering College, Ocean University of China, Qingdao 266071. China) Physical Oceanography Laboratory Ocean University of China Qingdao 266100China 2.engineering College Ocean University of China Qingdao 266071 China

Based on the maximum entropy principle,a probability density function (PDF) for the zero-crossing wave height (H) of random waves is derived as the simple form fn(H)=αHγe-βHn (n is a selectable positive integer) through solving a variational problem subject to some quite general constraints. This PDF maximizes the information entropy of H, and its parameters α, γ and β are expressed explicitly in terms of the distribution moments m, m=1.2,…,n, so it is well competent for describing the distribution of H of nonlinear sea waves with large uncertainty, and its parameters can be simply determined from available data. Comparisons between the PDF with n=3 and n=4 and the observed distributions of H from wave records measured in the east China Sea and in a wind-wave tunnel show fairly satisfying agreements.

关键词： sea waves the maximum entropy principle probability density function