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Science China Earth Sciences 2004年第12期47卷 1076-1084页

作者： CHEN Longxun 1 ,GAO Hui 2 ,HE Jinhai 2 ,TAO Shiyan 3 & JIN Zuhui 3 1.Chinese Academy of Meteorological Sciences,Beijing 100081,China 2.Nanjing institute of Meteorology,Nanjing 210044,China 3.institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China Chinese Academy of Meteorological Sciences Beijing China Nanjing institute of Meteorology Nanjing China Chinese Academy of Sciences Institute of Atmospheric Physics Beijing China

Zonal propagation of kinetic energy (KE) and convection in the South China Sea (SCS) and Indian summer monsoon areas are examined in present study. Results suggest that the SCS and Indian summer monsoon prevailed regions (5 —15°N) are dominated by the southwesterly wind, however, the disturbances of KE at 850 hPa and convection are observed mainly coming from the western Pacific Ocean (140—150°E), after passing through the SCS, and westward propagated into the Bay of Bengal (90—100°E). In the Indian summer monsoon domain, where the disturbances of KE are found mainly coming from the Arabian Sea (AS) and eastward propagated into the Bay of Bengal. Therefore, the SCS and the Indian summer mon- soon are quite different in zonal propagation of KE and convection. The SCS summer monsoon is mainly affected by the KE and convection coming from the tropical western Pacific. The Indian summer monsoon, however, can be partly influenced by the AS and the SCS summer monsoon. The analysis also suggests that the interaction region between the SCS and the Indian summer monsoon is around 90—95°E, rather than 105°E as proposed by earlier studies.

关键词： zonal propagation of KE and convection, East Asian monsoon, Indian monsoon.

Theoretical study of ZnO adsorption and bonding on Al_2O_3(0001) surface

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Science China(Physics,Mechanics & Astronomy) 2004年第6期47卷 664-675页

作者： LI Yanrong1,YANG Chun1,2,XUE Weidong1,LI Jinshan3 & LIU Yonghua3 1.institute of Microelectronics and Solid State Electronics,University of Electronic Science and Technol- ogy of China,Chengdu 610054,China 2.institute of Mathematics and Software Science,Sichuan Normal University,Chengdu 610068,China 3.institute of Chemical Materials,China Academy of Engineering Physics,Mianyang 621000,China institute of Microelectronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China institute of Mathematics and Software Science Sichuan Normal University Chengdu 610068 China institute of Chemical Materials China Academy of Engineering Physics Mianyang 621000 China

ZnO adsorption on sapphire (0001) surface is theoretically calculated by using a plane wave ultrasoft pseudo-potential method based on ab initio molecular dynamics. The results reveal that the surface relaxation in the first layer Al-O is reduced, even eliminated after the surface adsorption of ZnO, and the chemical bonding energy is 434.3(±38.6) kJ·mol?1. The chemical bond of ZnO (0.185 ± 0.01 nm) has a 30° angle away from the adjacent Al-O bond, and the stable chemical adsorption position of the Zn is deflected from the surface O-hexagonal symmetry with an angle of about 30°. The analysis of the atomic populations, density of state and bonding electronic density before and after the adsorption indicates that the chemical bond formed by the O2 of the ZnO ? and the surface Al3+ has a strong ionic bonding characteristic, while the chemical bond formed by the Zn2+ and the surface O2 has an obvious covalent characteristic, which ? comes mainly from the hybridization of the Zn 4s and the O 2p and partially from that of the Zn 3d and the O 2p.

关键词： α-Al2O3 (0001) ZnO ab initio molecular dynamics chemical adsorption density of states

Nanocrystallization of Cementite in 0.4C-1Cr Steel During High-Power Surface Processing

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Journal of Wuhan University of Technology(Materials Science) 2005年第3期20卷 60-63页

作者：赵新奇 School of Materials Science and Engineering Tongji University Shanghai Baosteel Research institute Shanghai 201900China

The microstructures of the nanocrystalline surface layer of a quenched and high temperature tempered 0. 4C- 1Cr steel induced by high-power surface processing （HPSP） technique were characterized by scan- ning eleetron microscopy and transmission electron microscopy. The results indicate that a nanocrystalline layer was fabricated on the surface of the steel 19 using HPSP treatment. The mean grain size in the surface layer is about 11 nm. The nanocrystallization of cementite is prior to that of the matrix phase, ferrite.

关键词： cementite high-power surface processing surface nanocrystallization

Construction and evaluation of reference standards for detection and quantification of Klebsiella pneumoniae using real-time PCR

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Journal of Pharmaceutical Analysis 2010年第3期22卷 183-187页

作者： Fei-Long Sun1,2,Min Jin3,Zhi-Gang Qiu3,Zhi-Qiang Shen3,Xin-Wei Wang3,Jun-Wen Li31.School of Life Science and Technology,Xi’an Jiaotong University,Xi’an 710049 2.School of Environmental and Chemical Engineering,Xi’an Polytechnic University,Xi’an 710048 3.institute of Environment and Health,Tianjin 300050,China School of Life Science and Technology Xi'an Jiaotong University Xi'an 710049 China School of Environmental and Chemical Engineering Xi'an Polytechnic University Xi'an 710048 China institute of Environment and Health Tianjin 300050 China

Objective To construct reference standards for detection and quantification of Klebsiella pneumoniae(***)with SYBR Green I-based real-time PCR *** Primers were designed based on the published sequence of the phoE gene of *** standard was prepared by cell culture,PCR and T-A clone methods,and was identified by colony PCR and DNA *** The standard curve showed a very good linear negative regression between threshold cycle(Ct)and Log starting quantity of copy *** detection range was from 5.2 to 5.2×106 copies per reaction,and the detection limit was 6 copies per *** coefficients of variance(CVs)of three parallel experiments were in the range of 0.05%-0.91%.Conclusion The reference standards have high stability and *** can be used in the quantitative detection of ***.

关键词： cloning vector Klebsiella pneumoniae real-time PCR standard

Corrosion and electrochemical behavior of as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys in 5%NaCl aqueous solution

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Progress in Natural Science:Materials International 2011年第4期21卷 314-321页

作者： Xin ZHANG~(1,2,3),Kui ZHANG~1,Xing-gang LI~1,Cong WANG~4,Hong-wei LI~(2,3),Chang-shun WANG~(2,3),Xia DENG~1 1.State Key Laboratory for Fabrication and Processing of Nonferrous Metals, Beijing General Research institute for Nonferrous Metals,Beijing 100088,China 2.Beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts,Beijing 100072,China 3.institute of Technology,Beijing North Vehicle Group Corporation,Beijing 100072,China 4.Fengtai Military Representative Office,Beijing Military Representative Office,PLA,Beijing 100072,China State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China Beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts Beijing 100072 China institute of Technology Beijing North Vehicle Group Corporation Beijing 100072 China Fengtai Military Representative Office Beijing Military Representative Office PLA Beijing 100072 China

The corrosion mechanism of the as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloy immersed in 5%NaCl aqueous solution was investigated by electrochemical test and *** electrochemical results indicate that the corrosion resistance of Mg-5Y-7Gd-1Nd-0.5Zr alloy in 5%NaCl aqueous solution gradually deteriorates with immersion time increasing from 2 h,24 h,60 h,to 108 h,which is consistent with the SEM observation of corrosion *** Cl-anion leads to the initiation and development of the corrosion pits,and Mg-5Y-7Gd-1Nd-0.5Zr alloy exhibits filiform type of attack under significant anodic control of magnesium solution *** corrosion potential becomes noble with increasing immersion time.

关键词： magnesium alloys Mg-5Y-7Gd-1Nd-0.5Zr corrosion electrochemical behavior

Meteorological observations on Mount Everest in 2005

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Progress in Natural Science:Materials International 2007年第7期17卷 828-837页

作者： Xie Aihong~(1**) Qin Dahe~1 Ren Jiawen~1 Qin Xiang~1 Xiao Cunde~(1,2) Hou Shugui~1 Kang Shichang~(1,3) Yang Xingguo~(1,4) Jiang Youyan~1 (1.Key Laboratory of Cryosphere and Environment,Cold and Arid Regions Environment and Engineering Research institute,Chinese Academy of Sciences,Lanzhou 730000,China 2.Chinese Academy of Meteorological Science,Beijing 100081,China 3.institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100085,China 4.Gansu Provincial Meteorological Bureau,Lanzhou 730000,China) Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Mount Everest,the highest point on the Earth is often referred to as the earth's third pole as such the place is relatively inaccessible and little is known about its *** April 2005,an automatic weather station was installed at the mountain's North Col(6523 m a.s.l.).According to the observational 10-minute mean and daily records,the meteorological characteristics were analyzed. All the meteorological elements displayed obvious diurnal variations during May 1 to July 22,*** monthly variation of daily meteo- rological elements on Mount Everest coincided with that on Dingri,the closest routine meteorological station,with the high correlation co- efficients of 0.928,0.877,0.682,0.755,0.826 and 0.676(n=83,p3,0.485 and 0.487(n=83,p<0.001),*** other weather events on Mount Everest lagged one-day be- hind those on ***,forecasting of the weather events on Mount Everest from pressure on Dingri was more reliable than those from the other meteorological *** conclusions are much important for research on meteorology and climate changes in the region.

关键词： Mount Everest meteorological observation Dingri County radiation air temperature relative humidity air pressure wind

Entropy of three-dimensional BTZ black holes

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中国科学：物理学、力学、天文学英文版 2004年第3期47卷 277-283页

作者： GAO Changjun1,2 & SHEN Yougen1,2,3,4 1.Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030,China(mailing address) 2.National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012,China 3.institute of Theoretical Physics,Chinese academy of Sciences,Beijing 100080,China 4.Shanghai United Center for Astrophysics,Shanghai 200234,China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China National Astronomical Observatories Chinese Academy of Sciences Beijing China institute of Theoretical Physics Chinese Academy of Sciences Beijing China Shanghai United Center for Astrophysics Shanghai China

The entropies of scalar field and neutrino field are calculated in the background of three-dimensional BTZ black hole. Considering statistical physics,we propose not to consider the superraradiant modes for bosons (Fermion fields do not display supperradiance).In fact,the nonsuperradiant modes do contribute exactly the area entropy for both bosons and fermions. The result shows that the neutrino field entropy is 3/2 times the scalar one.

关键词： BTZ black holes, entropy, supperradiant modes.

Important population viability analysis parameters for giant pandas(Aliuropoda melanoleuca)

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动物学研究 2012年第3期 18-24页

作者： Minghao GONG1,2,*,Yanling SONG2,Zhisong YANG3,Chen LIN1 1.Wildlife Monitoring Centre,Academy of Forest Inventory and Planning,State Forestry Administration,Beijing 100714,China 2.institute of Zoology,the Chinese Academy of Sciences,Beijing 100101,China 3.institute of Rare Animals and Plants,China West Normal University,Nanchong 637002,China

Population viability analysis(PVA) is a tool to evaluate the risk of extinction for endangered species and aid conservation *** quality of PVA output is dependent on parameters related to population dynamics and life-history;however,it has been difficult to collect this information for the giant panda(Aliuropoda melanoleuca),a rare and endangered mammal native to China,confined to some 30 fragmented habitat *** giant pandas are long-lived,mature late,have lower reproductive rates,and show little sexual dimorphism,obtaining data to perform adequate PVA has been ***,we develop a parameter sensitivity index by modeling the dynamics of six giant panda populations in the Minshan Mountains,in order to determine the parameters most influential to giant panda *** data shows that the giant panda populations are most sensitive to changes in four female parameters:initial breeding age,reproductive rate,mortality rate between age 0 and 1,and mortality rate of *** parameter sensitivity index strongly correlated with initial population size,as smaller populations were more sensitive to changes in these four *** model suggests that demographic parameters of females have more influence on the results of PVA,indicating that females may play a more important role in giant panda population dynamics than ***,reintroduction of female individuals to a small giant panda population should be a high priority for conservation *** findings form a technical basis for the coming program of giant panda reintroduction,and inform which parameters are crucial to successfully and feasibly monitoring wild giant panda populations.

关键词： Giant panda PVA Population parameter Parameter sensitivity index

Developmetn stage threshold of watershed Landforms in Loess Plateau and separation of erosion mechanism

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Journal of Geographical Sciences 2002年第1期12卷 81-90页

作者： LU Zhong-chen1, CHEN Shao-feng2,YUAN Bao-yin3,CHEN Hao4 (1.Eco-Environment Research Center,CAS,Beijing 100085,China 2.institute of Policy andManagement Science,CAS,Beijing 100080,China 3.institute of Geology,CAS,Beijing1000029,China 4.institute of Geograp

Threshold is a limit and marginal point when a qualitative change takes place. Since threshold principle was firstly used in landform research by *** in the 1970s, the quantitative research on watershed landform development stage has come true. Davis proposed a three-stage model on landform evolution: young, mature and old stages. Thereafter Strahler quantified this model by hypsometric analysis method. The authors thought that the material movement stage cannot be expressed by hypsometric method in watershed landform at development stage, because of the uncertainty on stage delimitation. To meet this shortcoming, this paper presents an integral erosion value method. A clear delimitation on landform development stage in the Loess Plateau region has been tested by this method. The result shows that gullied loessial hilly area is at the mature stage, and gullied loessial tableland area is at the young stage. It is estimated that from the point of erosion related sediment yield, natural erosion accounts for 70% of the total erosion amount, and artificial accelerating erosion is 30%. Therefore soil and water conservation is very crucial for the Loess Plateau.

关键词： landform development stage hypsometric analysis method integral erosion value natural erosion artificial accelerating erosion

The Self-assembling and Application of Inorganic Anti-bacterial Material Made of Natural Nanoporous Carrier

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Journal of Wuhan University of Technology(Materials Science) 2008年第6期23卷 771-774页

作者：孙春宝 School of Civil and Environmental Engineering University of Science and Technology Beijing

The inorganic antimicrobial material was inhibited to the microbes with the added metal ion,*** primary wet product carrying 5%-10% zinc ion was generated under the following conditions：temperature was 95 ℃,solution zinc concentration was 1.2-2.0 mol/L,and the ratio of Zn solution to zeolite weight was 5：*** final stable product was manufactured after baking in an oven for 1-3 h at the temperature of 500-900 ℃.The baked material was tested for its disinfection effectiveness and coloring effect when mixed with paint *** on the final batch of tests,the zinc content of this anti-microbial product was further optimized.

关键词： inorganic antimicrobial nanoporous material antibacterial coating zeolite self-assembling