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Refraction of light in media

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Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 591-600页

作者： ZHANG Tao Key Laboratory of Beam Technology and Material Modification of Ministry of Education, institute of Low energy Nuclear Physics, beijing Normal University, beijing 100875,{4. beijing Radiation Center, beijing 100875,{4. Key Laboratory of Beam Technology and Material Modification of Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing China beijing Radiation Center Beijing China

The roles of the magnetic field and electric field of the light are investigated when the light is refracted in the medium. The model of the electron cloud conductor is presented. Electron cloud in a molecule is treated as a conductor and the Faraday’s Law is applied to this conductor that is in the alternating magnetic field of the light. dBM/dt of the light gives rise to an alternating induced current on the electron cloud conductor, and the light exchanges energy, i.e. the refractive energy, with the elec- tron cloud conductor. Formulas of refractive index, which is the ratio of light speed in vacuum to that in the medium, are derived with this model. These formulas are tested with several mediums and Langevin’s diamagnetic susceptibility of helium gas, and the results are in good agreement with the measured data. The anisotropy and the nonlinearity of the refractive index are explained with the theory described in this work.

关键词： refractive index, light, speed, medium, propagation

Investigation on Systematic Trend of Shape Evolution for the Os Nuclei

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Investigation on Systematic Trend of Shape Evolution for the...

Determination of the ^(12)C(p, γ)^(13)N reaction rates fromthe ^(12)C(~7Li,~6He)^(13)N reaction

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： Li Guangsheng china institute of atomic energy,{4. 102413

The energies,in particular the lifetimes of the first excited states in even-even nuclei provide a worthful information about the quadrupole deformation of the nuclear *** the even-even Os isotopes （Z=76） with neutron numbers N≤126,the systematics of the excited energies of the first 2 states indicates that Os（N=108） has maximal *** the N=108 towards the closed shell at N=82,nuclear shape changes slightly with decreasing neutron *** from Os to Os,the quadrupole deformationβ（E） extracted from the energies of the 2 excited states remain almost constant at about 0.23. This behavior may be related to the possible X（5） structures for these *** systematicses of the excited energies for both the 2 states and with the addition of the 4.states show similar trend of shape evolution and make an appearance of a maximal deformation at Os for the even-even Os nuclei.

关键词： excited energy level lifetime shape evolution

来源： cnki会议评论

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 658-663页

作者： LI ZhiHong, SU Jun, GUO Bing, LI ZhiChang, BAI XiXiang, LIU JianCheng, LI YunJu, YAN ShengQuan, WANG BaoXiang, WANG YouBao, LIAN Gang, ZENG Sheng, LI ErTao, CHEN YongShou, SHU NengChuan, FAN QiWen & LIU WeiPing china institute of atomic energy,{4., china china institute of atomic energy Beijing China

The angular distribution of the 12C(7Li,6He)13N reaction at E(7Li) = 4..0 MeV was measured at the HI-13 tandem accelerator of beijing, china. The asymptotic normalization coefficient (ANC) of 13N → 12C + p was derived to be (1.64.± 0.11) fm-1/2 through the distorted wave Born approximation (DWBA) analysis. The ANC was then used to deduce the astrophysical S (E) factors and reaction rates for the 12C(p,γ)13N direct capture reaction at energies of astrophysical relevance.

关键词： the 12C(7Li 6He)13N reaction DWBA analysis asymptotic normalization coefficient astrophysical S(E)-factor

Response synchronization: New progress in brain-visual information processing

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Chinese Science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry , institute of Atmospheric Physics , Chinese Academy of Sciences , beijing 100029, china 2. Commission of the National Natural Science Foundation of china , beijing 100083, china 3. The Center of Information Science , Peking University, beijing 100871, china 4. Open Laboratory of Visual Information Processing , institute of Biophysics , Chinese Academy of Sciences , beijing 100101, china State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National Natural Science Foundation of china Beijing China The Center of Information Science Peking University Beijing China Open Laboratory of Visual Information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. Naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

ICRPANDCHINESERADIATIONPROTECTIONCOMMUNITY

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辐射防护 1998年第Z1期18卷 75-80页

作者： Pan Ziqiang(Science and Technology Commission, china atomic energy Authority, beijing) 核工业总公司安防环境保护卫生局北京

１ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｅｒｎａｔｉｏｎａｌＣｏｍｍｉｓｉｏｎｏｎＲａｄｉａｔｉｏｎＰｒｏｔｅｃｔｉｏｎ（ＩＣＲＰ）ｗａｓｅｓｔａｂｌｉｓｈｅｄｉｎ１９２８ａｓｔｈｅＩｎｔｅｒｎａｔｉｏｎａｌＸｒａｙａｎｄ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｅｒｎａｔｉｏｎａｌＣｏｍｍｉｓｉｏｎｏｎＲａｄｉａｔｉｏｎＰｒｏｔｅｃｔｉｏｎ（ＩＣＲＰ）ｗａｓｅｓｔａｂｌｉｓｈｅｄｉｎ１９２８ａｓｔｈｅＩｎｔｅｒｎａｔｉｏｎａｌＸｒａｙａｎｄＲａｄｉｕｍＰｒｏｔｅｃｔｉｏｎＣ...

关键词： ICRP Radiation Protection Regulations Radiation Protection Optimization

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth Sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2, WANG Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4.1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51064., china 2. Graduate University of Chinese Academy of Sciences, beijing 100039, china 3. SHRIMP isotope Laboratory, Chinese Academy of Geological Sciences, beijing 100037, china 4. institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of Chinese Academy of Sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4.± 3.0 Ma and 230.4.± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1977±4. Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

Kinetics study on the dissolution of UO_2 particles by microwave and conventional heating in 4.mol/L nitric acid

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Science china Chemistry 2008年第7期51卷 700-704页

作者： ZHAO YunFeng & CHEN Jing institute of Nuclear and New energy Technology, Tsinghua University, beijing 102201, china institute of Nuclear and New energy Technology Tsinghua University Beijing China

The dissolution of UO2 particles in 4.mol·L-1 nitric acid medium at temperatures of 90-110℃ by mi- crowave heating and conventional heating has been investigated, respectively. It is found that the dissolution ratios of UO2 particles by microwave heating were 10%-4.% higher than that by conven- tional heating. Kinetics research shows that the dissolution of UO2 particles in 4.mol·L-1 nitric acid is controlled by the diffusion control model for microwave heating and by the surface reaction control model for conventional heating. The diffusion control model for the dissolution of UO2 particles by mi- crowave heating could be explained by the diffuseness on the surface of UO2 particles.

关键词： uranium dioxide nitric acid dissolution microwave heating

A SIMPLE WAY CONSTRUCTING SYMPLECTICRUNGE-KUTTA METHODS

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Journal of Computational Mathematics 2000年第1期18卷 61-68页

作者： Geng Sun(institute of Mathematics, Academia Sinica, beijing 100080, china) 中科院数学所北京 100080

Presents a study which derived a way of constructing symplectic methods with the help of symplecticity conditions of partitioned Runge-Kutta methods. Classes of symplectic Runge-Kutta methods; Relationship between Run... 详细信息

关键词： symplecticity condition partitioned Runge-Kutta method

Experimental study of ore gabbro liquid immiscibility

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Science china Earth Sciences 2005年第4期48卷 496-505页

作者： SANG Zunan1,2, XIA Bin1, ZHOU Yongsheng3 & JIN Zhenmin4.1. Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51064., china 2. Wuhan University, Wuhan 4.0072, china 3. institute of Geology, china Seismological Bureau, beijing 100029, china 4. Faculty of Earth Sciences, china University of Geosciences, Wuhan 4.0074. china Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China Wuhan University Wuhan China institute of Geology China Seismological Bureau Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, china. Experiments were conducted under (confining) pressure ranging from 4.0 to 500 MPa and temperature of 900— 1200℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.