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research on Jiuquan-Jiayuguan-Yumen Region's Dynamic Changing of Urbanization Based on Self-Organizing Model

chinese Journal of Population,resources and Environment 2005年第3期3卷 22-28页

作者： Li Ming 1,2 & Fang Chuanglin 2 1 Graduate School of the chinese academy of sciences, Beijing 100039,china 2 institute of geographical sciences and natural resources research, CAS, Beijing 100101, china Graduate School of the chinese academy of sciences Beijing 100039 China institute of geographical sciences and natural resources research CAS Beijing 100101 China

Based on the self-organizing modeling principle in the dissipative structure theory, the paper regards the migration coupling between the regions as the influence factor to create the model of regional urbanization simulation and prediction, which is more practical to simulate the space-time and dynamic evolvement characteristics of regional urbanization level. According to the historical data about the population and urbanization of Jiuquan, Jiayuguan andYumen cities, the past 50 years' dynamic evolvement trend is simulated and the following 50 years' dynamic evolvement trend is predicted with the urbanization dynamic evolvement model based on the self-organizing model. The analysis of effective factors such as economic increase, resources exploitation, ecosystem construction, traffic location, national policies, population migration are given, then the reasons of the dynamic evolvement differences of the three cities' urbanization are drawn. The study suggests that the self-organizing model is fit for the simulation of Jiuquan-Jiayuguan-Yumen regional urbanization level in the past 50 years, and the departure between the stimulant and the actual data is under 5%, so it can be used to predict the urbanization future of the three cities. The predicted results show that the regional population will reach 1.074 million and the regional urbanization level will be 72.56%.

关键词： self-organizing urbanization dynamic evolvement Jiuquan-Jiayuguan-Yumen region

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Sandstorms and desertification

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Journal of geographical sciences 2000年第3期10卷 99-102页

作者： CHEN Zhi-qing1, ZHU Zhen-da2 (1.institute of geographic sciences and natural resources research, chinese academy of sciences, Beijing 100101, china 2. institute of Dsert research, chinese academy of sciences, Beijing 100101, china)

Sandstorm is a frequently occurred disastrous weather in northern china. The increasing occurrence frequency recently, especially the much more frequently occurred sandstorms with high intensity in the spring of 2000 have caused great loss to national economy. The combination of strong wind, exposed sandy soil on ground surface and unstable air current constitutes the necessary conditions for the sandstorms. However, the accelerated desertification process resulting from irrational human economic activities is responsible for the accelerated sandstorms. The effective measures to mitigate sandstorm lie in strengthening desertification control and eco-environmental protection.

关键词： sandstorm generating conditions desertification eco-environmental protection

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Role of P,S and B on Creep Behavior of Alloy 718

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Journal of Materials Science & Technology 2001年第4期17卷 399-402页

作者： Zhuangqi HU, Hongwei SONG, Shouren GUO and Wenru SUN institute of Metal research, The chinese academy of sciences, Shenyang 110016, china chinese Acad Sci Inst Met Res Shenyang 110016 Peoples R China

The doping of phosphorus, sulfur and boron in IN718 superalloy can remarkably influence the creep behavior. The modifications of the minor elements seem not to vary the stress exponent and the influences primarily concentrate on the effective diffusion coefficient. A pronounced beneficial interaction between P and B and a weaker detrimental interaction between P and S have been obtained. The preexponential frequency constant is proved to be strongly related with the creep activation energy because of the so-called compensation effect. The compensation temperature has been determined to be about 1080 K, which corresponds to the transformation temperature from rapidly coarsened γ'' phase to δ phase. It has been proposed that trace elements can influence the effective diffusion coefficient individually or cooperatively, which in turn either retard or speed the creep process.

关键词： Role of P S and B on Creep Behavior of Alloy 718

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Effects of cosmological constant on motion of UHECR particles

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Science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 44-56页

作者： CHEN Shaoxia & CHANG Zhe institute of High Energy Physics, chinese academy of sciences, Beijing 100039, china Graduate School of chinese academy of sciences, Beijing 100039, china institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China Graduate School Chinese Academy of Sciences Beijing 100039 China

Recent astronomical observations manifest that about two-thirds of the whole energy in the Universe is contributed by a small positive cosmological constant A (> 0). Then, an asymptotically de Sitter spacetime is premised naturally. However, physics in the de Sitter spacetime is very different from that in the Minkowski spacetime. As the first step, a covariant formalism of the kinematics in the de Sitter spacetime is presented here. By solving exactly the equations of motion for a field, we obtain the dispersion relation of a free particle. It is noticed that the dispersion relation is dependent on the degree of freedom of angular momentum of the particle. We show the threshold anomaly of the ultra high energy cosmic ray disappears naturally in the framework of the de Sitter kinematics.

关键词： ultrahigh energy cosmic ray, cosmological constant, curved spacetime.

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A study on sustainable development capacity of china's coastal areas using indices dimension reduction method

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Journal of geographical sciences 2000年第4期10卷 28-36页

作者： WANG Li-ming, YANG Yan-feng, MAO Han-ying, CHEN Wei-min (institute of geographic sciences and natural resources research, chinese academy of sciences, Beijing 100101, china) 中科院地理科学与资源所北京

Sustainable Development Capacity (SDC) is a comprehensive concept. In order to obtain a relatively objective evaluation of it, many indices of various aspects are often used in assessing index systems. However, the overlapping information of indices is a frequent source deviating the result from the truth. In this paper, 48 indices are selected as original variables in assessing SDC of china's coastal areas. The mathematical method of dimension reducing treatment is used for eliminating the overlapping information in 48 variables. Five new comprehensive indices are extracted bearing efficient messages of original indices. On the base of new indices values, the sequencing of 12.coastal areas SDC is gained, and five patterns of sustainable development regions are sorted. Then, the leading factors and their relations of SDC in these patterns are analyzed. The gains of research are discussed in the end.

关键词： sustainable development capacity dimension reduction china's coastal areas

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Functionally assessing the sustainability of regional ecosystem services:a case study of Hohhot City

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research in Cold and Arid Regions 2010年第2期2卷 175-184页

作者： Ling Feng institute of geographic sciences and natural resources research,chinese academy of sciences,Beijing 100101,china institute of geographic sciences and natural resources research Chinese Academy of SciencesBeijing 100101China

"The value of the world’s ecosystem services and natural capital" by *** et *** 1997 is generally regarded as a monument to the research of valuing ecosystem ***,the classification of ecosystem services,the method of various services summation,and the purpose for static global value had many *** on a summary of these criticisms and suggestions,further study direction—on the sustainability of ecosystem services—is *** two basis indicators in ecology—productivity and biodiversity,respectively characterize the ability of producing and self-organizing—not only represent the internal function of ecosystem,but also can be proportioned to its external function of supporting and providing for human ***,the two indicators combined could physically assess the sustainability of ecosystem services based on the traditional procedure of Costanza’*** case study of Hohhot City in 1995-2005 shows that the new model reflects the changes of ecosystem services at spatial and temporal scale,and the functionally adjusted assessment shows the sustainability of Hohhot City became gradually stronger during the study *** due to the enormous value per unit of water ecosystem,the minimal loss of water area leads to the final result being opposite to the processing analysis,which gives a clue to the further experimental testing research.

关键词： ecosystem services sustainability bio-productivity biodiversity

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Introduction to the Special Issue on Eco-compensation in china

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Journal of resources and Ecology 2015年第6期6卷 353-354页

作者： XIE Gaodi institute of geographic sciences and natural resources research, CAS Professor of institute of geographic sciences and natural resources research CAS Email: xiegd@igsnrr.ac.cnAddress:11-A Datun Road Anwai Chaoyang District Beijing 100101 China

Owing to emphasis on economic growth since 1978 the ecological and environmental problems are continuously emerging in china especially in the river source areas and ecological fragile areas of china and thus,these areas have to face the conflict between economic development and environmental *** a result,it is an urgent need to establish a scientific and reasonable ecological compensation mechanism to coordinate the contradiction.

关键词：生态补偿机制生态环境问题生态脆弱地区经济增长环境保护经济发展科学合理河流

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Stability of proton and maximally symmetric minimal unification model for basic forces and building blocks of matter

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 303-310页

作者： WU YueLiang institute of Theoretical Physics, chinese academy of sciences, Beijing 100080, china 1. institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China

With the hypothesis that all independent degrees of freedom of basic building blocks should be treated equally on the same footing and correlated by a possible maximal symmetry, we arrive at a 4-dimensional space-time unification model. In this model the basic building blocks are Majorana fermions in the spinor repre- sentation of 14-dimensional quantum space-time with a gauge symmetry GM4D = SO(1,3)×SU(32)×U(1)A×SU(3)F. The model leads to new physics including mirror particles of the standard model. It enables us to issue some fundamental questions that include: why our living space-time is 4-dimensional, why parity is not con- served in our world, how the stability of proton is, what the origin of CP violation is and what the dark matter can be.

关键词： gauge symmetry space-time symmetries beyond standard model and unification

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Oxygen Isotope Exchange Kinetics Between Coexisting Minerals and Water in the Aral Granite Pluton of the Altay Mountains, Northern Xinjiang

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Acta Geologica Sinica(English Edition) 1996年第4期70卷 366-379,452页

作者： Liu Wei,research Center of Mineral resources Exploration, chinese academy of sciences, chinese academy of sciences, BeijingHe Baichu, Changsha institute of Geotectonics, chinese academy of sciences, Changsha, Hunanand Chen ZhenshengYichang institute of Geology and Mineral resources, chinese academy of Geologicalsciences, Yichang, Hubei

Coexisting quartz, feldspar and biotite vary widely in their δ18O values and display a remarkable 18O/16O disequilibrium relation; especially, a quartz-feldspar reversal (△ 18OQUartz_feldspar< 0) exsists in the Aral granite pluton of the Altay Mountains, northern Xinjiang. The 18O / 16O exchange reaction definitely occurred between granite and water. Initial δ18O values of the granite and exotic fluid are evaluated by the mass balance consideration. The conventional method of discrimination between various magma derivations simply with δ18O values of either whole rock or separate minerals is misleading and unreliable. Experiments carried out by the authors show that the 18O / 16O exchange reaction is not accompanied by what geologists describe as petrological and mineralogical alteration effect. This decoupling relation implies that exchange reaction occurs at a relatively high temperature during subsolidus-postmagmatic cooling of magmas. The exchange mechanism is mainly diffusion-controlled. It is demonstrated through quantitative modelling that the hydrothermal system associated with the Aral pluton is long-lived (0.8-6 Ma), with a relatively high fluid flow rate (3 ×10-14 mol. s-1) and high W/ R ratio (0.79-6.14). This means that an intense flow and convection may exist at the midcrustal level of erogenic magmatic arcs.

关键词： kinetics oxygen isotope exchange reaction granite Aral of Xinjiang

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Vibration Effects on the Structural Stability of Al-Ti Intermetallics by First-principles Calculations

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Journal of Materials Science & Technology 2010年第12期26卷 1071-1077页

作者： Hui Zhang and Shaoqing Wang Shenyang National Laboratory for Materials Science,institute of Metal research,chinese academy of sciences,Shenyang 110016,china [a] Shenyang National Laboratory for Materials Science institute of Metal research chinese academy of sciences Shenyang 110016 china

The structural stability of the intermetallics AlTi3, Al2Ti, Al3Ti4 and Al3Ti in the Al-Ti system has been investigated using density functional theory （DFT） and density functional perturbation theory （DFPT）. The calculated ground-state convex hull is in agreement with the experimental researches. Al3Ti4 （hP7） is metastable at 0 K and may be stabilized as the temperature increases due to the effects of the vibration entropy. For Al2Ti, r-Al2Ti is stable at 0 K and h-Al2Ti is stabilized by the vibration entropy at high temperatures. Al3Ti （tI16） is unstable considering vibration effects and Al3Ti （tI8） is the most stable structure at 0 K.

关键词： First-principles Al-Ti Vibration Crystal structure

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