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AGRICULTURAL HAIL DAMAGE AND ITS SEASONAL REGIONALIZATION IN china

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Natural Disaster Reduction in china 2003年第3期 24-27页

作者： Wang Ying1, Wang Jingai2. Wu Wenbin3.and Li Wenhang2.(1. Institute of Resource Sciences, beijing Normal {3., Key Laboratory of Environment Change and Natural Disaster,Ministry of Education of{2., beijing 100875 2.Department of Resources and Environmental Sciences, beijing Normal {3., beijing 100875,{2. 3.Institute of Natural Resources and Regional Planning, Chinese Academy of Agriculture Sciences, beijing 100087,{2.)

According to the hail damage database of china, both the damage affected area and seriously affected area show a descending trend, while the ratio of the latter to the former ascends on the contrary. The seasonal variation of hail damage is quite obvious, spring and summer are the main periods of time of hail shooting throughout the whole country, and the frequency of hail shooting during April～September accounts for 92.3. of whole year. The distribution zone of hail shooting and seriously hail damage-affected area have an evident difference, and the center of hail damage is located in the Huang-Huai-Hai Plain and hilly regions on the south of the Yangtze River. Based on the map of county-level seasonal hail damage and the map of agriculture comprehensive regional planning, this paper designs the seasonal regionalization of hail damage by the methods of “from top to bottom” and “from bottom to top”, and china is divided into 5 types of hail damage zones with 16 second regions and 2. thrid regions. The 5 types are: summer type (I); later-spring/early-summer and summer type (II); later-spring and early-summer and double peak type (III); spring type (IV); summer and double peak type (V).

关键词： hail damage agriculture seasonal regionalization china

A local f-x Cadzow method for noise reduction of seismic data obtained in complex formations

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Petroleum Science 2011年第3期8卷 269-277页

作者： Yuan Sanyi Wang Shangxu State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China

A noise-reduction method with sliding called the local f-x Cadzow noise-reduction method, windows in the frequency-space （f-x） domain, is presented in this paper. This method is based on the assumption that the signal in each window is linearly predictable in the spatial direction while the random noise is not. For each Toeplitz matrix constructed by constant frequency slice, a singular value decomposition （SVD） is applied to separate signal from noise. To avoid edge artifacts caused by zero percent overlap between windows and to remove more noise, an appropriate overlap is adopted. Besides flat and dipping events, this method can enhance curved and conflicting events. However, it is not suitable for seismic data that contains big spikes or null traces. It is also compared with the SVD, f-x deconvolution, and Cadzow method without windows. The comparison results show that the local Cadzow method performs well in removing random noise and preserving signal. In addition, a real data example proves that it is a potential noise-reduction technique for seismic data obtained in areas of complex formations.

关键词： Cadzow sliding window noise reduction fidelity complex formations Toeplitz matrix,singular value decomposition

Petrography,mineral chemistry and shock metamorphism of Yamato 98402. lherzolitic shcrgottite

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Petrography,mineral chemistry and shock metamorphism of Yama...

EFFECT　OF　TRACE　ELEMENTS　WITH　ZERO　SELF－INTERACTIONCOEFFICIENT　ON　CRYSTALLIZATION　TEMPERATUREOF　IRON　CARBON　ALLOYS

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： HU Sen~(1,2.,FENG Lu~(1,2. & LIN YangTing~(1*) 1 Key Laboratory of the Earth’s Deep Interior,Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing 10002.,china 2.{2. university of Chinese Academy of Sciences,beijing 100049,china

Y98402. is a new lherzolitic shergottite,consisting of poikilitic and non-poikilitic *** mafic silicates are FeO-poor, and the chromite is TiO-poor in the poikilitic lithology compared to the grains in the non-poikilitic *** meteorite shares similar mineral petrography and mineral chemistry with GRV 9902.,but is not paired with the latter because of their different shock-induced features.Y98402. was severely shocked and experienced no significant thermal metamoiphism after the main impact ***,Y98402. serves as a probe for the study of meteorite impact processes on terrestrial *** melt veins in Y98402. are characterized by the absence of any high-pressure polymorphs,the presence of abundant small mineral fragments,and the prevailing granulation textures of olivine and *** features are consistent with adiabatic melting during the release of shock-induced high-pressure and quenching at ambient pressure.

关键词： Mars shergottite Iherzolite Antarctica shock metamorphism

来源： cnki会议评论

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Acta Metallurgica Sinica(English Letters) 1996年第3期9卷 232-234页

作者： ZHAI Qijie and HU Hanqi(Department of Foundry, university of Science and Technology beijing, beijing 100083.{3.)

The effect of trace elements with zero self-interaction coefficient on crystallization temperature of iron carbon alloys was studied and the mathematic equation was developed based on thermodynamics in the present researeh. With the equation developed in this paper, the effects of nitrogen on crystallization temperature of Fe-3.45C-2.15Si0. 16Mn and Fe-3.45C-2. 15Si-0. 80Mn alloys were discussed.

关键词： trace element iron carbon alloy crystallization temperature,self-interaction coefficient

Interferon-alfa in the treatment of chronic hepatitis B

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Hepatobiliary & Pancreatic Diseases International 2004年第3期3卷 337-340页

作者： Fu-Kui Zhang Liver Research Center, beijing Friendship Hospital,Capital university of Medical Sciences, beijing 100050 ,{3. Liver Research Center Beijing Friendship Hospital Capital University of Medical Sciences Beijing 100050 China. frankliver@***

BACKGROUND: Interferon-alfa has been used in the treat-ment of chronic hepatitis B for more than 2. years and hasits own advantages including a definite course of therapy,no production of drug-resistant variants, and sustained effi-cacy. This review was to understand the role of interferon-alfa therapy in chronic hepatitis *** RESOURCES: An English-language literature searchusing Medscape and MEDLINE was performed and a totalof 48 articles on the treatment of chronic hepatitis with in-terferon-alfa or pegylated interferon-alfa were ***: Interferon-alfa therapy was associated with ahigher HBV DNA inhibition rate and HBeAg loss rate com-pared with controls, and it may have long-term beneficialeffects in terms of HBV clearance, reduction of hepatocel-lular carcinoma, and prolongation of survival. Pegylatedinterferon-alfa was more effective than conventional inter-feron-alfa in the treatment of chronic hepatitis B as well aschronic hepatitis C, and was also associated with greater ef-ficacy than conventional interferon in difficult-to-treat ***: Interferon-alfa is still regarded as one ofthe first-line drugs for the treatment of chronic hepatitis *** interferon is a more promising therapy than con-ventional interferon-alfa, especially in patients with refrac-tory chronic hepatitis B.

关键词： chronic hepatitis B interferon pegylated interferon lamivudine

Learning interactions among multi-channel sequences with dynamical influence models

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Science china(Information Sciences) 2010年第7期53卷 1336-1344页

作者： ZHANG WeiDong, CHEN Feng & XU WenLi Department of Automation, National Laboratory for Information Science and Technology, Tsinghua university, beijing 100084,{2. Department of Automation National Laboratory for Information Science and Technology Tsinghua University Beijing China

Many real applications involve simultaneous recording and analysis of multi-channel information sources. Learning and modeling the interactions among channels is the kernel step to analyze and recognize system characteristics. This paper presents a model that learns the dynamical influence among multi-channel sequences. The model, dynamical influence model, permits functional roles of individual channels to change and models the changing influence strength between channels. By querying the values of influence factors, we can recognize the functional role of each channel qualitatively and learn about to what extent the chains influence each other quantitatively at any time. The experimental results on synthetic data and application of multi-person interaction recognition show that our model is reliable and effective.

关键词： multi-channel processing dynamical interaction influence model activity recognition

Thermodynamic conditions of framework grain dissolution of clastic rocks and its application in Kela 2.gas field

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Science china Earth Sciences 2005年第1期48卷 21-31页

作者： LAI Xingyun, YU Bingsong, CHEN Junyuan, CHEN Xiaolin, LIU Jianqing, MEI Mingxiang, JING Weiguang & CHENG Suhua School of Earth Sciences and Mineral Resources, china university of Geosciences, {2. 100083. china Key Laboratory of Lithospheric Tectonics, Deep-level Process and Exploration of Ministry of Education, {2. 100083. china china university of Geosciences School of Earth Sciences and Mineral Resources Beijing China Key Laboratory of Lithospheric Tectonics Deep-level Process and Exploration of Ministry of Education Beijing China

Feldspar and clastic debris are the most important constituent framework grains of sedimentary clastic rocks and their chemical dissolution plays an essential role in the formation and evolution of the secondary pore in the reservoir rocks. On the basis of thermodynamic phase equilibrium, this study investigates the chemical equilibrium relationships between fluid and various plagioclase and K-feldspar in diagenesis of the sediments, particularly, the impact of temperature and fluid compositions (pH, activity of K+, Na+, Ca2. and so on) on precipitation and dissolution equilibria of feldspars. Feldspar is extremely easily dissolved in the acid pore water with a low salinity when temperature decreases. The dissolution of anorthite end-member of plagioclase is related to the Ca content of the mineral and the fluid, higher Ca either in the mineral or in the fluid, easier dissolution of the feldspar. Moreover, the dissolution of albite end-member of plagioclase is related to Na of both the mineral and fluid, lower Na out of both the mineral and fluid, easier dissolution of the mineral. Similarly, lower-K fluid is more powerful to dissolve K-feldspar than the higher. The anorthite component of plagioclase is most easily dissolved in ground water-rock system, the albite is the secondary, and K-feldspar is the most stable. Selective dissolution of plagioclase occurs in diagenesis because of the plagioclase solid solution that is mainly composed of albite and anorthite end-members, Ca-rich part of which is preferentially dissolved by the pore water, in contrast to the Na-rich parts. Based on investigation of reservoir quality, secondary pore, dissolution structures of feldspar, clay minerals and ground water chemistry of the Kela 2.gas field of Kuqa Depression in the Tarim basin of Western china, we discovered that the secondary pore is very well developed in the highest quality section of the reservoir, and the plagioclase of which was obviously selectively dissolved, in c

关键词： dissolution of feldspar, thermodynamic conditions, groundwater pore chemistry, Kela 2 gas field.

On the use of simplex methods in constructing quadratic models

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Science china Mathematics 2007年第7期50卷 913-924页

作者： Qing-hua ZHOU 1 College of Mathematics and Computer,Hebei university,Baoding 071002.china 2.State Key Laboratory of Scientific and Engineering Computing,Institute of Computational Mathematics and Scientific/Engineering Computing,Academy of Mathematics and Systems Science,Chinese Academy of Sciences,{2. 100080,china College of Mathematics and Computer Hebei University Baoding China State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China

In this paper, we investigate the quadratic approximation methods. After studying the basic idea of simplex methods, we construct several new search directions by combining the local information progressively obtained during the iterates of the algorithm to form new subspaces. And the quadratic model is solved in the new subspaces. The motivation is to use the information disclosed by the former steps to construct more promising directions. For most tested problems, the number of functions evaluations have been reduced obviously through our algorithms.

关键词： unconstrained optimization trust region method quadratic model Lagrange function simplex methods direct methods 90C56

Functional characterization of a biosurfactant-producing thermo-tolerant bacteria isolated from an oil reservoir

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Petroleum Science 2011年第3期8卷 353-356页

作者： Wang Jing Ji Guang Tian Jing Zhang Hongdan Dong Hanping Yu Li College of Chemical Engineering China University of Petroleum Beijing 102249 China Langfang Branch Research Institute of Petroleum Exploitation and Development China National Petroleum Corporation Hebei 065007 China

A Bacillus subtilis strain JA-1 isolated from an oil reservoir was studied. This strain is capable of growth and producing biosurfactant at a temperature of 60 ℃. In nutrient medium it produced biosurfactant which reduced the surface tension from 68.2.mN/m to 2..3.mN/m, with the critical micelle concentration （CMC） of 48 mg/L. The measured surface tension indicated that the biosurfactant possessed stable surface activity at high temperature and a specific range of pH and salt concentrations. The results of thin layer chromatography （TLC） together with FT-IR showed that the metabolic product of strain JA-1 is a lipopeptide biosurfactant. The ability to growth at high temperature and to produce biosurfactant makes strain JA-1 promising for enhanced oil recovery.

关键词： Biosurfactant bacillus subtilis lipopeptide surface tension critical micelle concentration(CMC)