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Ecological rebuilding and land reclamation in surface mines in Shanxi Province, china

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Journal of Environmental Sciences 2000年第4期12卷 486-497页

作者： MIAO Ze wei 1, BAI Zhong ke 2. GAO Lin 1 (1. Research center for Eco Environmental Sciences, Chinese Academy of Sciences, beijing 100085,{2. E\|mail: miaozewei@*** 2. Department of Soil Science, Shanxi Agricultural University Taigu, 03 中科院生态环境研究中心北京 1 0 0 0 85 山西师范大学山西临汾 0 3 0 80 1

It is well known that the mining industry produces a large amount of derelict land, and causes pollution of water loss and soil erosion as well as other environmental damage in china. As land is under pressure in china, it is now policy to restore or reclaim land despoiled by mining, the aim being to develop sustainable and healthy arable land ecosystems. This paper outlines the principles and approaches of ecological restoration, which have been adopted in Shanxi Province with reference to three typical surface mines. In the research, the principles of ecological engineering and ecological succession are considered as the critical theories of ecological restoration in mine degraded land. Meanwhile, the paper made a comparative research on main links of ecological rebuilding in three surface mines in Shanxi Province, which include new land construction, treatment of toxic substances, control of soil erosion, fertility management, irrigation, ecological planning and the establishment of legislation systems. As the research demonstrated, for successful restoration, new land construction is the fundamental framework, but it must be integrated with ecological engineering including ecological planning, the control of soil erosion and vegetation establishment and ecosystem creation in order to optimise land productivity and soil fertility. In addition, the establishment of the legislation systems and organization of administration are also indispensable aspects of ecological rebuilding in mined land.

关键词： ecological restoration land reclamation open-pit mine

A numerical simulation on the infrared radiation of hot exhausting nozzles with a coupled flow and heat transfer model

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Science china(Technological Sciences) 2010年第10期53卷 2699-2707页

作者： HU HaiYang1 & WANG Qiang2.1 china Academy of Aerospace Aerodynamics, beijing 100074, china 2.School of Jet Propulsion, Beihang University, beijing 100191, china china Academy of Aerospace Aerodynamics Beijing China School of Jet Propulsion Beihang University Beijing China

A coupled model among flow field,solid temperature,species concentration and gas radiation,which was based on statistical narrow-band correlated-k model,was employed to predict the infrared radiations from hot exhausting nozzles. The parameters of narrow-band model were deduced from HITEMP line-by-line database. Several methods to increase computational efficiency and to save computational resources were employed,thus all the complicated computations could be operated on a personal computer. The predictions for three cases have been conducted to validate the accuracy of the methods mentioned above,including the temperature distribution of a water-cooling nozzle in rocket engines,the carbon dioxide absorptivity at the wavelength of 4.3 micron and the infrared radiation of a cylindrical furnace. Finally,the aerothermodynamic and infrared characteristics of two nozzles were predicted. It was shown that the infrared radiation intensity of chevron ejecting nozzle were obviously smaller than that of common axisymmetric convergent-divergent nozzle.

关键词： infrared radiation numerical simulation exhausting nozzles coupled model

Structural characteristics of the Tan-Lu fault zone in Cenozoic basins offshore the Bohai Sea

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Science china Earth Sciences 2008年第S2期51卷 20-31页

作者： QI JiaFu1,2.ZHOU XinHuai3,DENG RongJing4 & ZHANG KeXin2.1 State Key Laboratory of Petroleum Resource and Prospecting,china Petroleum University,beijing 102.49,china 2.Department of Earth Sciences,china Petroleum University,beijing 102.00,china 3 Tianjin Branch of CNOOC china Limited,Tianjin 300451,china 4 beijing Research center of CNOOC china Limited,beijing10002.,china State Key Laboratory of Petroleum Resource and Prospecting China Petroleum University Beijing China Department of Earth Sciences China Petroleum University Beijing China Tianjin Branch of CNOOC china Limited Tianjin China beijing Research center of CNOOC{2. Limited Beijing China

The Tan-Lu fault zone across the eastern margin of the Cenozoic basins offshore the Bohai Sea is a NNE-trending right-lateral strike-slip fault system developed in the Cenozoic basin cover. It cuts through NE-to NNE-striking major extensional faults that controlled the formation of Paleogene basins. Recent petroleum exploration indicates that Cenozoic structural activities of the Tan-Lu fault system have directly or indirectly affected oil and gas distribution offshore the Bohai Sea. As part of a deep fault zone the Tan-Lu fault zone has been activated since the Oligocene,and obviously affected the tectonic evolution of offshore Bohai basins since then. The formation of Paleogene rift basins offshore the Bohai Sea has utilized the pre-existing structural elements of the Tan-Lu fault zone that developed in the late Mesozoic.

关键词： strike-slip fault extensional structure Tan-Lu fault zone Bohaiwan basin

The multi-factor recombination and processes superimposition model for hydrocarbon accumulation:application to the Silurian in the Tarim Basin

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Petroleum Science 2008年第1期5卷 13-19页

作者： Meng Qingyang Pang Xiongqi Gao Jianbo State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Basin and Reservoir Research center China University of Petroleum Beijing 102249 China Research center CNOOC Beijing 100027 China

The multi-factor recombination and processes superimposition model for hydrocarbon accumulation is put forward in view of the hydrocarbon geological characteristics of multiple episodes of structural evolution, multiple sets of source-reservoir-seal assemblage, multiple cycles of hydrocarbon accumulation and multiple episodes of readjustment and reconstruction in the complex superimposed basins in china. It is a system including theories and methods that can help to predict favorable exploration regions. According to this model, the basic discipline for hydrocarbon generation, evolution and distribution in the superimposed basins can be summarized in multi-factor recombination, processes superimposition, multiple stages of oil filling and latest stage preservation. With the Silurian of the Tarim basin as an example, based on the reconstruction of the evolution history of the four factors （paleo-anticline, source rock, regional cap rock and kinematic equilibrium belt） controlling hydrocarbon accumulation, this model was adopted to predict favorable hydrocarbon accumulation areas and favorable exploration regions following structural destruction in three stages of oil filling, to provide guidance for further exploration ofoil and gas in the Silurian of the Tarim basin.

关键词： Multi-factor recombination processes superimposition Tarim Basin Silurian favorable exploration region prediction

Assimilation of temperature and salinity using isotropic and anisotropic recursive filters in Tropic Pacific

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Acta Oceanologica Sinica 2011年第1期30卷 15-23页

作者： LIU Ye ZHAO Yanling National Marine Environmental Forecasting center Beijing 100081 China No 61741 Army Troop Beijing 10081 China

A data assimilation scheme used in the updated Ocean three-dimensional Variational Assimila- tion System （OVALS）, OVALS2. is described. Based on a recursive filter （RF） to estimate the background error covariance （BEC） over a predetermined scale, this new analysis system can be implemented with anisotropic and isotropic BECs. Similarities and differences of these two BEC schemes are briefly discussed and their impacts on the model simulation are also investigated. An idealized experiment demonstrates the ability of the updated analysis system to construct different BECs. Furthermore, a set of three years experiments is implemented by assimilating expendable bathythermograph （XBT） and ARGO data into a Tropical Pacific circulation model. The TAO and WOA01 data are used to validate the assimilation results. The results show that the model simu- lations are substantially improved by OVALS2. The inter-comparison of isotropic and anisotropic BEC shows that the corresponding temperature and salinity produced by the anisotropic BEC are almost as good as those obtained by the isotropic one. Moreover, the result of anisotropic RF is slightly closer to WOA01 and TAO than that of isotropic RF in some special area （e.g. the cold tongue area in the Tropic Pacific）.

关键词： recursive filter anisotropic isotropic background error covariance

Fluorescence response of hypocrellin B to the environmental changes in a mimic biological membrane——liposome

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Science china Chemistry 2004年第4期47卷 335-339页

作者： JIN Xuanye1,2. ZHAO Yuewei1, XIE Jie1 & ZHAO Jingquan1 1. CAS Key Laboratory of Photochemistry, center for Molecular Science, Institute of Chemistry, Chinese Academy of Science, beijing 100080,{2. 2. School of Earth Sciences and Resources,{2. University of Geosciences, beijing 100083,{2. CAS Key Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Science Beijing China School of Earth Sciences and Resources China University of Geosciences Beijing China

Liposome is well known as not only a drug-delivery system but also a simple model for biological membranes. It was reported that fluorescence properties of hypocrellins were changeable over some extreme pH values. In the current work, the effects of the microenvironments on the fluorescence properties of HB in liposome, including approximately physiological range of pH values pH = 6.0-8.0, concentration of cholesterols and ionic strength of the solution, were studied. It was found that the fluorescence intensity of HB was sensitive to and also regulated by the microenvironments. When concentration of cholesterols and ionic strength keep invariable in PBS solution, there exists the maximum for the fluorescence of HB-liposome at pH 7.4 while the minimum for that of HB at pH 7.0. In addition, when pH value keeps constant (7.2., there exists the maximum at the ionic strength of 0.12.mol/kg while that at the concentration of 6×10?4 mol/L for cholesterols. On the other hand, in PBS solution, the lower the ionic strength is, the higher the fluorescence intensity is. The environment-sensitive fluorescence may be potentially applicable to probe some specific environmental features in cells or tissues.

关键词： microenvironment hypocrellin B liposome fluorescence

Graphene-based hybrid materials and their applications in energy storage and conversion

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Chinese Science Bulletin 2012年第23期57卷 2983-2994页

作者： ZHOU Ding 1,2.CUI Yi 1,2.& HAN BaoHang 1,2.1 National center for Nanoscience and Technology,beijing 100190,{2. 2.State Key Laboratory of Transducer Technology,Chinese Academy of Sciences,Shanghai 2.0050,{2. National center for Nanoscience and Technology Beijing China State Key Laboratory of Transducer Technology Chinese Academy of Sciences Shanghai China

Graphene attracts more and more scientists and researchers owing to its superior electronic,thermal,and mechanical *** material scientists,graphene is a kind of versatile building blocks,and considerable progress has been made in recent ***-based hybrid materials have been prepared by incorporating inorganic species and/or cross-linking of organic species through covalent and/or noncovalent *** graphene-based hybrid materials show improved or excellent performance in various *** this review,we summarize the synthesis of graphene and graphene-based hybrid materials,and their applications in energy storage and conversion.

关键词： graphene hybrid material energy storage energy conversion

Progress in china’s climate change study in the 2.th century

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Journal of Geographical Sciences 2004年第S1期 5-13页

作者： ZHAI Panmao1,2. CHAO Qingchen1,2. ZOU Xukai1,2.1. Laboratory for Climate Studies, china Meteorological Administration, beijing 100081, china 2. National Climate center, china Meteorological Administration, beijing 100081, china)

Studies on the 2.th century climate change in china have revealed that under the background of global warming over the past century, climate in china has also experienced significant change with mean annual temperature increased by about 0.5 oC. More reliable results for the latter part of the 2.th century indicate that the largest warming occurred in Northwest china, North china and Northeast china, and the warming in winter is most significant. Although no obvious increase or decrease trends were detected for mean precipitation over china in the past half century, regional differences are very distinct. In the middle and lower reaches of the Yangtze River, precipitation increased, while that in the Yellow River Basin markedly decreased. Studies suggest that climate change in china seems to be related not only with the internal factors such as ENSO, PDO, and the others, but also with the anthropogenic effects such as greenhouse gas emissions, and land use. The future climate change studies in china seem to be important in narrowing understanding the nature of china's climate change and its main causes, since it is significant for projection and for impact assessment of climate change in the future.

关键词： th century climate change china

Study on the unified algorithm for three-dimensional complex problems covering various flow regimes using Boltzmann model equation

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Science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 124-138页

作者： LI ZhiHui1,2.& ZHANG HanXin1 1 National Laboratory for Computational Fluid Dynamics, beijing 100083, china 2.1} Aerodynamics Research and Development center, Hypervelocity Aerodynamics Institute, Mianyang 62.000, china National Laboratory for Computational Fluid Dynamics Beijing China china Aerodynamics Research and Development center Hypervelocity Aerodynamics Institute Mianyang China

The Boltzmann simplified velocity distribution function equation describing the gas transfer phenomena from various flow regimes will be explored and solved numerically in this study. The discrete velocity ordinate method of the gas kinetic theory is studied and applied to simulate the complex multi-scale flows. Based on the uncoupling technique on molecular movement and colliding in the DSMC method, the gas-kinetic finite difference scheme is constructed to directly solve the discrete velocity distribution functions by extending and applying the unsteady time-splitting method from computational fluid dynamics. The Gauss-type discrete velocity numerical quadrature technique for different Mach number flows is developed to evaluate the macroscopic flow parameters in the physical space. As a result, the gas-kinetic numerical algorithm is established to study the three-dimensional complex flows from rarefied transition to continuum regimes. The parallel strategy adapted to the gas-kinetic numerical algorithm is investigated by analyzing the inner parallel degree of the algorithm, and then the HPF parallel processing program is developed. To test the reliability of the present gas-kinetic numerical method, the three-dimensional complex flows around sphere and spacecraft shape with various Knudsen numbers are simulated by HPF parallel computing. The computational results are found in high resolution of the flow fields and good agreement with the theoretical and experimental data. The computing practice has confirmed that the present gas-kinetic algorithm probably provides a promising approach to resolve the hypersonic aerothermodynamic problems with the complete spectrum of flow regimes from the gas-kinetic point of view of solving the Boltzmann model equation.

关键词： Boltzmann model equation kinetic theory velocity distribution function discrete velocity ordinate technique hypersonic flow parallel computing numerical methods