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Optimal reactions for the synthesis of superheavy nucleus ^(2.0)Hs

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Science china(Physics,{1. & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1.3 & BAO Jingdong1.2.1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, {1. Normal University, {1. 1.0875,{2. 2. Physics Department, {1. Normal University, {1. 1.0875,{2. 3.{2. institute of Atomic Energy, {1. 1.2.1.,{2. Key Laboratory of Beam Technology Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China Physics Department Beijing Normal University Beijing 100875 China china {1. of Atomic Energy Beijing 102413 China

The superheavy nucleus 2.0Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 2.8Cm(2.Mg,4n)2.0Hs, 2.4Pu(30Si,4n)2.0Hs, 2.8U(36S,4n)2.0Hs and 2.6Ra(48Ca,4n)2.0Hs using a two-parameter Smoluchowski equation. It is found from our results that 2.6Ra(48Ca,4n)2.0Hs and 2.8U(36S,4n)2.0Hs are two optimal reactions for the synthesis of the superheavy nucleus 2.0Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

Progress and review of the studies on the end-Triassic mass extinction event

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Science china Earth Sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1.2. LU Yuanzheng1.2.3 & XU Daoyi4 1. Research institute of Petroleum Exploration and Development, {1. 1.0083,{2. 2. Key Laboratory of Oil and Gas Reservoir of Petrochina, {1. 1.0083,{2. 3.{2. University of Geosciences, {1. 1.0083,{2. 4. institute of Geology,{2. Earthquake Administration, {1. 1.002.,{2. 1. Research institute of Petroleum Exploration and Development 100083 Beijing China 2. Key Laboratory of Oil and Gas Reservoir of Petro{1. 100083 Beijing China 3. china University of Geosciences 100083 Beijing China 4. institute of Geology China Earthquake Administration 100029 Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. china has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

A subsurface runoff parameterization with water storage and recharge based on the Boussinesq-Storage Equation for a Land Surface Model

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Science china Earth Sciences 2006年第6期49卷 622-631页

作者： TIAN Xiangjun1.2. XIE Zhenghui1. ZHANG Shenglei1.& LIANG Miaoling1.1. LASG, {1. of Atmospheric Physics, Chinese Academy of Sciences, {1. 1.002.,{2. 2. Graduate School of the Chinese Academy of Sciences, {1. 1.0039,{2. 1. LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Subsurface runoff in a land surface model is usually parameterized as a single-valued function of total storage in a basin aquifer reservoir. This kind of parameterization is often sin-gle-valued function of storage-discharge under a steady or “quasi-steady” state, which cannot rep-resent the influence of aquifer recharge on subsurface runoff generation. In this paper, a new sub-surface runoff parameterization with water storage and recharge based on the Boussinesq-storage equation is developed. This model is validated by a subsurface flow separation algorithm for an ex-ample river basin, which shows that the new model can simulate the subsurface flow reasonably.

关键词： Zsubsurface runoff parameterization Boussinesq-storage equation waterstorage and recharge

Photogeneration of the free radicals and singlet oxygen by chrysophanol from rheum

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Science china Chemistry 2004年第5期47卷 381-387页

作者： RAO Jing1.2. XIE Jie1. ZHAO Jingquan1.& ZHU Teng2.1. Key Laboratory of Photochemistry, Center for Molecular Science, institute of Chemistry, The Chinese Academy of Sciences,{1.,{2. 2. University of Science and Technology beijing, beijing 1.083,{2. 1. Key Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry The Chinese Academy of Sciences 100080 Beijing China 2. University of Science and Technology {1. 10083 Beijing China

In the current work, chryosphanol (MHAQ) was isolated and purified from rheum, and the photosensitization activities were studied. In nitrogen-saturated DMSO solution, irradia- tion of chryosphanol (MHAQ) with visible light (>430 nm) produced the semiquinone radical anions (MHAQ??), which was intensified significantly by an electron donor NADH, suggesting electron transfer between the excited and ground state photosensitizer molecules. In an air-saturated DMSO solution, superoxide radical anions (O2.), trapped by DMPO, were detected. ?? It was proved that O2.was not originated from the singlet oxygen (1.2. but dependent on DMPO, ?? chrysophanol, oxygen and the irradiation time. The singlet oxygen and OH could also be pro- ? duced by the photosensitization of the photosensitizer. These suggest that chrysophanol pos- sesses the photosensitization activity via Type I mechanism and Type II mechanism. To evaluate the photosensitization activities of MHAQ, emodin and mixed anthraquinone derivatives ex- tracted from rheum, the relative productivities of O2.were estimated to be 1.8, 1.1.and 1.0 re- ?? spectively and the quantum yields for singlet oxygen to be 0.36, 0.53 and 0.1. respectively. Therefore, these low-cost pigments may be potentially used as phototherapeutic medicine for some kind of vascular diseases or photo-activated pesticides.

关键词： chrysophanol, ESR, semiquinone radical anions, superoxide radical anions, hydroxyl radical, singlet oxygen.

Geological analysis and physical modeling of structural pumping in high effective formation of Kela 2.gas field

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Science china Earth Sciences 2006年第10期49卷 1070-1078页

作者： ZHAO Wenzhi1. WANG Hongjun1. SHAN Jiazeng2. WANG Zecheng1.& XU Dafeng1.1. Research {1. of Petroleum Exploration and Development, Petro{1., {2. 1.0083, china 2. {1. of Geology and Geophysics, Chinese Academy of Sciences, {2. 1.002., china 1. Research institute of Petroleum Exploration and Development Petrochina Beijing 100083 China 2. {1. of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

In a 3-D closed geological body, in case “structural expanding” inside is induced by stress, it can produce the pressure difference between the expanding cell and surrounding rock, then generate a pumping force directed toward the cell and accelerate the directional flow of fluid in the strata. The structural style and conditions of gas reservoir-formation in the Kuqa depression are favorable to the structural pumping. According to similarity principle, a physical modeling of structure formation and gas filling process of the Kela 2.gas field has justified the occurrence of structural pumping and its important role in gas-reservoir formation with high efficiency under the compressive and well-sealed circumstance. Therefore, authors propose that structural pumping is an important mechanism of gas reservoir-formation with high efficiency in the Kuqa depression.

关键词： Kela 2 gas field, structural pumping, gas-reservoir formation mechanism, high efficiency,physical modeling.

Y_CΩ_(2.)are easy terms

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Chinese Science Bulletin 1998年第20期43卷 1707-1709页

作者： ZHAO Xishun 1.and WANG Ju 2.1. Department of Mathematics, Nanjing University, Nanjing 2.0093, china 2. {1. of Software, Chinese Academy of Sciences,{2., china Department of Mathematics Nanjing University Nanjing China institute of Software Chinese Academy of Sciences Beijing China

For any natural number n≥1. Y CΩ 2. is an easy term; that is, for any λ term M, λβ+Y\-CΩ 2. =M is consistent, where Y C is Curry fixed point combinator, Ω 2. ≡ω 2. ω 2. and ω 2. ≡λ***...x (there are 2. occurrences of x after λx ). This result is a partial solution to Jacopini’s conjecture: Y CΩ n is an easy term for any natural number n≥2.

关键词： λβ-calculus Kuper’s theorem easy term.

Structural characteristics and petroliferous features of Tarim Basin

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Chinese Science Bulletin 2002年第S1期47卷 1-11页

作者： JIA Chengzao~1.& WEI Guoqi~2.1. Petro{1. Company Limited, {1. 1.001.,{2. 2. Langfang Branch of Research institute of Petroleum Exploration & Development, Petro{1., Langfang 065007,{2. 1. Petrochina Company Limited 100011 Beijing China 2. Langfang Branch of Research {1. of Petroleum Exploration & Development PetroChina 065007 Langfang China

Using the modern tectonic geology theories andmethods such as the plate tectonic analysis, the paleo-struc-ture analysis, the structural-Iithofacies analysis, and the faultrelated fold and petroleum system, and combining with theseismic data, well drilling data and the circumferential fieldgeology, study on the structural characteristics and petro-leum prospect in the Tarim Basin has been carried out. Re-sults show that the Tarim Basin is a large superimpositionand combination basin with continental crustal basement,composed of a Paleozoic craton and Meso-Cenozoic forelandbasins. The characteristics of the basin are: the kernel partof the basin is the marine facies Paleozoic craton, superim-posed 4 continental facies foreland basins. Though the scaleof the paleozoic craton of the Tarim Basin is relatively small,the structure is steady. The petroleum prospect of the Paleo-zoic craton is: multiphase pool-generation and accumulationcontrolled by ancient uplift. The Meso-Cenozoic forelandbasins in the Tarim Basin, which are distributed on the era-tonic circumference and are a long-term subsidence, turnedinto rejuvenated foreland basins after the Meso-Cenozoicperiod. The petroleum prospects are: coal-bed generatinghydrocarbon, abundant natural gas, pool-generation in laterand recent periods, the oil and gas distribution controlled bythe foreland thrust belt. The structural characteristics ofTarim provide it with a superimposition and combinationpetroleum system of multiple resources, multiple reservoirsand multiphase pool-generation. The oil and gas explorationprospect covers two large fields: the Paleozoic craton and theMeso-Cenozoic foreland thrust belt.

关键词： Tarim superimposition and combination basin craton foreland basin superimposition and combination petroleum system.

Comparative study of the effect of Cu_2. and MoO_3 on flame retardance and smoke emission of PVC by Cone and TGA

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Chinese Science Bulletin 1998年第13期43卷 1090-1094页

作者： LI Bin\+1.and WANG Jianqi\+2.1. Department of Chemistry, Northeast Forestry University, Harbin 1.0040,{1. 2. National Laboratory of Flame Retardant Materials, {1. {2. of Technology, {1., 1.0081.{1. Department of Chemistry Northeast Forestry University Harbin China National Laboratory of Flame Retardant Materials Beijing Institute of Technology Beijing China

Cuprous and molybdic oxides exhibit extremely effectiveness in smoke suppression for PVC. However, few are the data reported concerning flame retardance and smoke emission of PVC taken from Cone calorimetry relative to the conventional thermal analysis technique. Abundant data from Cone calorimetry have been acquired. Data analysis was achieved through the study of MLR, HRR, SEA tested at irradiance of 2. kWm -2.. The understandable flame retardance of PVC/Cu\-2. and PVC/MoO\-3 relative to pure PVC has been rationalized by their lowered heat release rates and enhanced char residues. The difference in smoke reduction between these two oxides consists in the time scale. As clearly seen under air atmosphere both oxides exert themselves to the afterglow which has been recognized as a dangerous source, in particular in the full_scale fire situation.

关键词： cone calorimetry poly(vinyl chloride) flame retardation smoke emission cuprous oxide molybdic oxide.

Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing,{1.

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Science china Earth Sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1. LIANG Tao1.& TAO Shu2.1. {1. of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, {1. 1.01.1.{2. 2. Laboratory for Earth Surface Processes, Peking University, {1. 1.0871.{2. 1. institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1.5{1.{1.03 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1.5{1.1.83, the average input and output amount of HCHs through agricultural application and degradation are 1.0 t and 1.0 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1. 1. t?a?1.and 1. t?a?1. which account for 9{1. of total transfer fluxes of HCHs isomers. There were approximately {1.3t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1.84 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1.83, and this percentage may descend to 0.5% after {1. years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.