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Isospin-dependent relativistic microscopic optical potential in the Dirac Brueckner-Hartree-Fock method

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 189-198页

作者： RONG Jian1 & MA Zhongyu1,2.3.1. china Institute of Atomic {2., beijing 102.13. china 2. Center of Nuclear Theoretical physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lan-zhou 73.000, china 3. Institute of Theoretical physics, chinese academy of sciences, beijing 100080, china correspondence should be addressed to Rong Jian (email: jrong@***) 1. china Institute of Atomic energy 102413 Beijing China 2. Center of Nuclear Theoretical physics National Laboratory of Heavy Ion Accelerator of Lanzhou 730000 Lanzhou China 3. Institute of Theoretical physics Chinese Academy of Sciences 100080 Beijing China

The relativistic microscopic optical potential in the asymmetric nuclear matter is studied in the framework of the Dirac Brueckner-Hartree-Fock method. A new decomposition of the Dirac structure of the nuclear self-energy in nuclear matter is adopted. The self-energy of a nucleon with E > 0 in nuclear matter is calculated with the G matrix in the Hartree-Fock approach. The optical potential of a nucleon in the nuclear medium is identified with the nucleon self-energy. The energy and asymmetric parameter dependence of the relativistic optical potentials for proton and neutron are discussed. The resulting Schroedinger equivalent potentials have reasonable behaviors of the energy dependence. The asymmetric parameter dependence of relativistic optical potentials and Schroedinger potentials are emphasized.

关键词： Dirac Brueckner Hartree-Fock, relativistic microscopic optical potential, asymmetric nuclear matter, isospin-dependence.

Fuzzy cluster analysis of the provenance of ancient Yaozhou porcelain body

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chinese Science Bulletin 2003年第1期48卷 27-30页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2. XIE Jianzhong1, FENG Songlin3. FAN Dongyu3. ZHANG Ying3. CAI Zhifang3. ZHUO Zhenxi4 & GAO Zhengyao1 1. Faculty of Physical Engineering, Zhengzhou University, Zhengzhou 450052. china 2. Department of physics, beijing Normal University, beijing 100875, china 3. high energy physics Institute, the chinese academy of sciences, beijing 100080, china 4. Archaeology Research Institute, Shanxi Province, Xian 710000, china correspondence {13. be addressed to Li Guoxia (e-mail: Liguoxia@ ***) Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China Department of physics Beijing Normal University Beijing 100875 China high energy {2. Institute Chinese Academy of Sciences Beijing 100080 China Archaeology Research Institute Shanxi Province Xi'an 710000 China

The technique of neutron activation analysis (NAA) has been employed to measure the content of 2. kinds of elements in the sample of Yaozhou porcelain bodies. Then a fuzzy cluster analysis has been conducted to the NAA data and a diagram of the dynamic fuzzy cluster analysis has been achieved. The results indicate that the batch of ancient Yaozhou porcelain bodies, which were of different overglaze color and were produced by different kilns during a period of over 800 years from the Tang Dynasty (618—907 A.D.) to the Yuan Dynasty (12.1—13.8 A.D.), has shared a stable and concentrated raw material source. Provenances of por-celain bodies from different times, though having their spe-cific independence, enjoy a close relationship and are not far from one another. Provenances of porcelain bodies made during the Tang Dynasty and the Five Dynasties (907—960 A.D.) are found to be closer to one another, while those of the Song (960—12.9 A.D.) and the jin Dynasty (1115—12.0} A.D.) are comparatively concentrated in certain areas and are dif-ferent from those of the Tang Dynasty. Both the tri-colored glazed pottery made in Yaozhou kilns during the Tang Dy-nasty and the Yaozhou porcelain bodies of the Tang period are from the same provenance.

关键词：古代姚州瓷胎窑址粘土矿原料来源中子活化分布模糊聚类分析

Electronic Structure of the Clusters Containing Oxygen in Ni

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Journal of Materials Science & Technology 1996年第6期12卷 427-433页

作者： Tao YU Chongyu WANG and Bing WANG (Central Iron and Steel Research Institute, beijing 100081, china)(To whom {2. {3. be addressed)( The International Centre for Materials physics of the chinese academy of sciences, Shenyang 110015, china) Central Iron and Steel Research Institute Beijing 100081 China International Centre for Materials physics Chinese Academy of Sciences Shenyang 110015 China

The electronic structure of the clusters containing oxygen, the stacking fault and the complex in the transition metal Ni are calculated by the multiple-scattering Xa method. energy levels,density of states and transfer of charge are obtained. Based on the calculation and analysis,the influences of impurity oxygen and structure defect on the electronic structure of the clusters are discussed, and it is found that the local Ni-o cluster with the interstitial oxygen is a stable atomic configuration.

关键词： Rev Electronic Structure of the Clusters Containing Oxygen in Ni Wang

Synthesis of new carbon nanomolecule: C141

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Science Bulletin 2004年第8期49卷 793-796页

作者： CHEN Zhenling, ZHAO Yuliang, QU Li, GAO Xingfa, ZHANG Jun, YUAN Hui, CHAI Zhifang, XING Gengmei & CHENG Yue Institute of high energy {2.,{3., beijing 100039, china correspondence should be addressed to Zhao Yuliang (zhaoyuliang@ ***) or Chai Zhifang (chaizf@mail.***) Institute of high energy {2. Chinese Academy of Sciences Beijing 100039 China

A new [70]fullerene dimer consisting of 141 carbon atoms was first synthesized by a new method with neutron irradiation of [70]fullerene. The results of separation and isolation with two-step HPLC (high performance liquid chromatography) show that this odd-numbered fullerene dimer is stable in air. Laser induced dissociation of C141 mainly yields fragmental species C70 and C71. The UV-vis spectrum of C141 shows that its vis feature is diminished as compared to that of C70. Experiments indicate that this new method for synthesis of fullerene dimers with neutron irra-diation has a high selectivity for formation of C2.-X-C2. type carbon nanomolecules.

关键词： C141 odd-numbered fullerene dimer neutron irradiation.

EXAFS study on arsenic species and transformation in arsenic hyperaccumulator

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Science china(Life sciences) 2004年第2期47卷 124-129页

作者： HUANG Zechun1, CHEN Tongbin1, LEI Mei1, HU Tiandou2.& HUANG Qifei1 1. Laboratory of Environmental Remediation, Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, {2. 100101, {3. 2. Laboratory of Synchrotron Radiation, Institute of high energy physics, chinese academy of sciences, beijing 100039, {3. correspondence should be {12. to Chen Tongbin 1. Laboratory of Environmental Remediation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. PLaboratory of Synchrotron Radiation Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

Synchrotron radiation extended X-ray absorption fine structure (SR EXAFS) was employed to study the transformation of coordination environment and the redox speciation of arsenic in a newly discovered arsenic hyperaccumulator, Cretan brake (Pteris cretica L. var ner-vosa Thunb). It showed that the arsenic in the plant mainly coordinated with oxygen, except that some arsenic coordinated with S as As-GSH in root. The complexation of arsenic with GSH might not be the predominant detoxification mechanism in Cretan brake. Although some arsenic in root presented as As(V) in Na2.AsO4 treatments, most of arsenic in plant presented as As(III)-O in both treatments, indicating that As(V) tended to be reduced to As(III) after it was taken up into the root, and arsenic was kept as As(III) when it was transported to the above-ground tissues. The reduction of As(V) primarily proceeded in the root.

关键词： hyperaccumulator, Cretan brake (Pteris cretica L. var nervosa Thunb), arsenic, species, EXAFS.

Degradation of 4-chlorophenol in aqueous solution by γ-radiation and ozone oxidation

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Science china Chemistry 2006年第2期49卷 186-192页

作者： HU Jun1, WANG Jianlong1,2.& CHEN Rong1 1. Laboratory of Environmental Technology, Institute of Nuclear energy Technology, Tsinghua University, beijing 100084, {2. 2. State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, beijing 100084, {2. correspondence should be addressed to Wang Jianlong 1. Laboratory of Environmental Technology Institute of Nuclear Energy Technology Tsinghua University Beijing 100084 China 2. State Key Joint Laboratory of Environmental Simulation and Pollution Control Tsinghua University Beijing 100084 China

The degradation of 4-chlorophenol (4-CP) by using gamma rays generated by a 60Co source in the presence of O3.was investigated. The radiolysis of 4-CP and the kinetics of 4-CP min-eralization were analyzed based on the determination of total organic carbon (TOC). The influence of initial 4-CP concentration and the free radicals scavengers (such as NaHCO3.and t-butanol) on the 4-CP degradation was also studied. The results showed that when the radiation rate was 3.6 Gy·min?1, 4-chlorophenol at concentration of 10 mg·L?1 could be completely degraded at the radiation dose of 2.kGy. The degradation of 4-chlorophenol could be described by a first-order reaction model, the rate constant of 4-CP degradation by combined ozonation and radiation was 0.1016 min?1, which was 2.4 times higher than the sum of radiation (0.02.4 min?1) and ozonation (0.013. min?1). It re-vealed that the combination of radiation and ozonation resulted in synergistic effect, which can re-markably increase the degradation efficiency of 4-CP.

关键词： radiolysis, 4-chlorophenol, priority pollutant, degradation, O3. synergistic effect, kinetics.

Effects of the disaggregation of high-polymerized particles in guard cell vacuoles on osmoregulation of stomatal aperture (stomata opening)

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chinese Science Bulletin 2003年第5期48卷 453-456页

作者： YE Qing, ZHU Guoli & LOU Chenghou Biology College, china Agricultural University, State Key Laboratory of Plant Physiology and Biochemistry, beijing 100094, china {3. should be addressed to Zhu Guoli (e-mail: glzhu@mail. ***) Biology College China Agricultural University State Key Laboratory of Plant Physiology and Biochemistry

Observation under an electron microscope reveals that in closed and open stomata of V. faba, the aver-age volume of particles in guard cell vacuoles (GCV) reduces about 3.orders in magnitude, while the distribution density of the particles increases about 2.orders of magnitude. By using the method of the ratio of fluorescent emissions with laser scanning confocal microscopy, the monitoring to sto-mata opening shows that during 10 to 3. s before the first distinguishable aperture of stomata, there is a change of pH in GCV about -0.5 units. A quick stomatal opening immedi-ately follows the changes of pH in GCV to reach a steady aperture about 12.mm in 1002.0 s. This work proposes a model for the osmoregulation in GCV for stomatal opening. The proposed osmoregulation is related to the disaggregation of some polymerized particles inside GCV, which is probably induced by a -DpH in the vacuole. This model describes a process of osmoregulation that avoids the massive {2. consuming transportation across cell membranes, which is a foundation of the current chemiosmotic hypothesis. This model is a supplement to the multiple controlling hypothesis for the stomatal movement, which widens research principle ideas for other quick movements in plants.

关键词：气孔运动气孔开放保卫细胞液泡渗透调节高聚合微粒解体

CHARACTERIZATION AND CATALYTIC BEHAVIOR OF WATER-SOLUBLE PHOSPHINE RHODIUM (I) COMPLEX

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Journal of energy Chemistry 1996年第2期 161-165页

作者： YAN Yuan -Yong ZUO Huan-Pei jin Zi-Lin (College of Chemital Engineering, Dalian University of Technology Dalian, beoning 116012.(To whom correspondence {2. be {3. Current address Institute of Chemistry The chinese academy of sciences beijing 1

The monosulfonated triphenylphospmme ligand , Ph2.(***3.) (abbr. as DPM). and its rhodium complex' HRh(COXDPM)3.have heen synthesized and charactcrized by spectroscopic techniques (IR,NMR) The obtained data showed that the structure of HRh(CO)(DPM)3.was similar to HRh(CO)(PPh3.3. The properties or HRh(CO)(DPM)3.as an oletin hydroformylation catalyst in aqueous-organic solvent two-phase system are studied

关键词： aqueous phase sulphonated phosphine characterization hydroformylation

A six-nucleotide insertion-deletion polymorphism in the CASP8 promoter is associated with susceptibility to multiple cancers

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A six-nucleotide insertion-deletion polymorphism in the CASP...