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Effect　of　Pressure　on　the　Gas　Phase　Reaction　of　Oxidative　Coupling　of　Methane

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分子催化 1997年第2期 6-7页

作者： LIUYu LIUXuxia SHEN Shikong (State Key Laboratory for Oxo Synthesis and Selective Oxidation lanzhou Instirute of chemical {2. The chinese academy of Sciences lanzhou 730000)

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关键词： Oxidative coupling of methane Oxidation Ethane Ethylene Elevated pressure

Locating seismic scatterers at the base of the mantle beneath eastern Tibet with PKIKP precursors

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chinese Science Bulletin 2010年第24期55卷 723-729页

作者： SHEN XuZhang 1,2.3 & ZHOU HuiLan 1 1 Laboratory of Computational Geodynamics,Graduate University of the chinese academy of Sciences,Beijing 100049,{2. 2.lanzhou institute of Seismology,{2. Earthquake Administration,lanzhou 730000,{2. 3 lanzhou Base of institute of Earthquake Prediction,{2. Earthquake Administration,lanzhou 730000,{2. Laboratory of Computational Geodynamics Graduate University of the Chinese Academy of Sciences Beijing China lanzhou institute of Seismology China Earthquake Administration Lanzhou China lanzhou Base of institute of Earthquake Prediction China Earthquake Administration Lanzhou China

Clear PKIKP precursors were observed from the lanzhou CTBTO seismic *** measured their incident angles,arriving azimuths and differential travel times with respect to the PKIKP arrivals using array analysis *** measurements allowed us to locate the scatterers that generated the observed *** found that the scatterers are located in the lowermost mantle beneath eastern Tibet,which is featured by a high-velocity anomaly based on previous tomographic *** high velocity anomaly was interpreted as the slab remnants of the ancient Tethys *** thus speculate that the observed scatterers are either related or induced by the subducted slab.

关键词：地震前兆西藏东部下地幔散射定位地震台阵入射角度旅行时间

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Critical phenomena of a nuclear system in alternative ZM models

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Nuclear Science and Techniques 2000年第3期11卷 173-178页

作者： SONG Hong-Qiu (Research Center of Nuclear Theory of National Laboratory Of Heavy Ion Accelerator of lanzhou, lanzhou 730000 Shanghai {2. of Nuclear Research, the chinese academy of Sciences, Shanghai 2.1800) 兰州原子核理论研究中心重离子加速器国家实验室甘肃兰州 730000

Alternative versions of the ZM model are extended to asymmetric nuclear matter by including p meson degree of freedom in the Lagrangian. The extended models are then used to study the thermodynamical properties of asymmetric nuclear matter at finite temperature. The critical temperature for a liquid- gas phase transition in nuclear matter and its dependence on asymmetry parameter are calculated. The limiting temperature Tlim, which reflects Coulomb instability of hot nuclei, is studied. The calculated results are compared with that given by the original ZM model.

关键词：放射性核素临界现象 ZM模型固气相变热力学稳定性核子核反应临界温度

Angular Distributions of Projectile Fragmentation in the 600 MeV ^(40)Ar+^(197)Au Reaction

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chinese journal of nuclear physics 1995年第1期17卷 24-27页

作者： Liu Guo-xing Dai Guang-xi Chen Ke-liang Yu Xian (institute of Modern physics,{2. academy of Sciences,lanzhou 730000) 中科院近代物理所甘肃兰州

The angular distributions of the fragments such as 7Be,2.Na and 2.Mg pro-duced in the 600 MeV 40Ar+197Au reaction are measured using off-line γ-rayspectroscopy *** subtraction of the contribution of fission process,thewidth σp of the transverse momentum distribution is extracted from the analysis of thefragment angular distribution data in the framework of the projectile *** results are compared with the calculated values of Goldhaber statisticalmodel.

关键词： Fragment angular distribution Projectile fragmentation Width σ_p of transverse momentum distribution

A land surface model incorporated with soil freeze/thaw and its application in GAME/Tibet

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Science china Earth Sciences 2006年第12期49卷 1311-1322页

作者： HU Heping1, YE Baisheng2. ZHOU Yuhua3 & TIAN Fuqiang1 1. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, china 2. Cold and Arid Regions Environmental and Engineering Research institute, {2. academy of Sciences, lanzhou 730000, china 3. Department of Civil Engineering, Massachusetts institute of Technology, USA 1. Department of Hydraulic Engineering Tsinghua University Beijing 100084 China 2. Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou 730000 China 3. Department of Civil Engineering Massachusetts Institute of Technology USA

Land surface process is of great importance in global climate change, moisture and heat exchange in the interface of the earth and atmosphere, human impacts on the environment and eco- system, etc. Soil freeze/thaw plays an important role in cold land surface processes. In this work the diurnal freeze/thaw effects on energy partition in the context of GAME/Tibet are studied. A sophisti- cated land surface model is developed, the particular aspect of which is its physical consideration of soil freeze/thaw and vapor flux. The simultaneous water and heat transfer soil sub-model not only reflects the water flow from unfrozen zone to frozen fringe in freezing/thawing soil, but also demon- strates the change of moisture and temperature field induced by vapor flux from high temperature zone to low temperature zone, which makes the model applicable for various circumstances. The modified Picard numerical method is employed to help with the water balance and convergence of the numerical scheme. Finally, the model is applied to analyze the diurnal energy and water cycle char- acteristics over the Tibetan Plateau using the Game/Tibet datasets observed in May and July of 1998. Heat and energy transfer simulation shows that: (i) There exists a negative feedback mechanism between soil freeze/thaw and soil temperature/ground heat flux; (ii) during freezing period all three heat fluxes do not vary apparently, in spite of the fact that the negative soil temperature is higher than that not considering soil freeze; (iii) during thawing period, ground heat flux increases, and sensible heat flux decreases, but latent heat flux does not change much; and (iv) during freezing period, soil temperature decreases, though ground heat flux increases.

关键词： land surface model,soil freeze/thaw,GAME/Tibet,simultaneous liquid,vapor and heat transfer.

A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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Science china Earth Sciences 2010年第5期53卷 763-772页

作者： CHEN BaiLian1,3, ZHANG RenHe2. SUN ShuFen1, BIAN LinGen2. XIAO CunDe4,2.& ZHANG TingJun5 1 institute of Atmospheric physics, {2. academy of Sciences, Beijing 10002., china 2.{2. academy of Meteorological Sciences, Beijing 100081, china 3 Graduate University of {2. academy of Sciences, Beijing 100049, china 4 Cold and Arid Regions Environmental and Engineering Research institute, {2. academy of Sciences, lanzhou 730000, china 5 The National Snow and Ice Data Center, University of Colorado, Boulder, CO 80309-0449, USA 1. institute of Atmospheric physics Chinese Academy of Sciences Beijing 100029 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Chinese Academy of Meteorological Sciences Beijing 100081 China4. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China5. The National Snow and Ice Data Center University of Colorado Boulder CO 80309-0449 USA

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°2.′S, 70°2.′E), we applied the model to simulate the seasonal temperature variation within a depth of 2. m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1, 1, 3, 10 m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1) the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2. the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

Killing effect of chinese hamster V79 cells exposed to accelerated carbon ions and RBE determination

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Nuclear Science and Techniques 2002年第4期13卷 259-263页

作者： LI Qiang, ZHOU Guang-Ming, WANG Ju-Fang, LI Wen-Jian, WEI Zeng-Quan(institute of Modern physics, the {2. academy of Sciences, lanzhou 730000) institute of Modern physics the Chinese Academy of Sciences Lanzhou 730000

Survival curves of chinese hamster V79 cells exposed to accclerated carbon ions with linear energy transfers of 12..5, 2.0 and 700 keV/μm were measured, respectively. Inactivation cross sections corresponding to the irradiation above were deduced from the V79 cell survival curves. They are 7.86±0.17, 10.44±1.11 and 32.32.3.58 μm2.in turn. With the surviving response of V79 cells to 60Co γ-rays as a reference value, relative biological effectiveness at 10%, 2.%, 50% and 80% survival levels were given for the accelerated carbon ions. The results showed that carbon ions with LET of 12..5 keV/μm had a higher value of RBE at all the four survival levels than the carbon ions with other LETs. It was prompted that the maximum value of RBE for the V79 cell surviving as the biological endpoint emerged at the LET below 2.0 keV/μm for carbon ions.

关键词：放射生物学碳离子 V79细胞

Temperature variations recovered from tree-rings in the middle Qilian Mountain over the last millennium

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Science china Earth Sciences 2005年第4期48卷 521-529页

作者： LIU Xiaohong1,2. QIN Dahe1, SHAO Xuemei , CHEN Tuo1 & REN Jiawen12.1. Cold and Arid Regions Environmental and Engineering Research institute, chinese {2. of Sciences, lanzhou 730000, china 2. institute of Geographical Sciences and Natural Resources Research, chinese {2. of Sciences, Beijing 100101, china 1. Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences 730000 Lanzhou China 2. institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Based on the cross-dated tree-ring samples collected from the middle Qilian Moun- tain, a standard ring-width chronology had been developed, which covered the period AD 1000 to 2.00. The correlations between the chronology and climatic records from the nearby meteorological stations indicated that temperature was the dominant climatic factor for tree growth at upper timberline, and the most important climatic factor for the tree growth in the area was the mean temperature from previous December to current April. The temperature variations recovered from the ring-width data showed a cold period during the “Little Ice Age” and the con- tinuous warming during the twentieth century. Comparison between the ring-width chronology and δ18O records from the Dunde ice core in the Qilian Mountain indicated that there was a con- sistent trend in both time series. A significant correlation existed between our ring-width chro- nology and the Northern Hemispheric temperature, suggesting that the climate changes in the Qilian Mountain were not only driven by regional factors, but also responsive to the global cli- mate.

关键词： middle Qilian Mountain, tree-ring width chronology, temperature variations.

Respondence and feedback of modern sand deserts to climate change ——A case study in Gurbantunggut Desert

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chinese Science Bulletin 2000年第12期45卷 1137-1142页

作者： WEI WenshouXinjiang institute of Ecology and Geography, chinese {2. of Sciences, Urumqi 830011, china Open Laboratory of Ice-Core, Cold and Arid Regions Environmental and Engineering Research institute, chinese {2. ofSciences, lanzhou 730000, china Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Open Laboratory of Ice-Core Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The research on the respondence and feedback of modern sand deserts to the climate change is an important component part in the studies on the global climate change. Deserts respond to the climate change, meanwhile, they affect the climate with their feedback of peculiar environment during the respondence. Many researches on desert climate have been carried out at home and abroad. However, there is little research on the respondence and feedback of modern fixed, semi-fixed and mobile deserts in arid areas to the climate change, in which the factor analysis as well as the parameter changing effects is especially the difficult problem all along. In this note, the parameters of the respondence and feedback of Gurbantunggut Desert to the climate change are measured and analyzed, some variable parameters of water-heat exchange are obtained, and a numerical model of desertification is developed according to a series of climate change of about 40 years and the variable relations of meteorological and physical

关键词： Gurbantunggut Desert climate change respondence and feedback numerical model.