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Deformation Stages and Ar-Ar Age Data of the Wan-Zhe-Gan Tectonic Zone,Southeast China,and Their Tectonic Significance 被引量:10
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作者 YU Xinqi WANG De'en +3 位作者 JIANG Dazhi JIANG Laili ZHOU Xiang LI Chunlin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第6期1373-1389,共17页
The major tectonic zone that passes through the border regions of the Anhui, Zhejiang, and Jiangxi Provinces in southeast China has been commonly referred to as the Wan-Zhe-Gan fault zone. Geologically, this zone cons... The major tectonic zone that passes through the border regions of the Anhui, Zhejiang, and Jiangxi Provinces in southeast China has been commonly referred to as the Wan-Zhe-Gan fault zone. Geologically, this zone consists of several regional fault belts of various ages and orientations. We have categorized the faults into four age groups based on field investigations. The Neoproterozoic faults are northeast striking. They start from the northeast Jiangxi Province and extend northeastward to Fuchuan in Anhui Province, the same location of the northeast Jiangxi-Fuchuan ophiolite belt. The faults probably acted during the Neoproterozoic as a boundary fault zone of a plate or a block suture with melange along the faults. The nearly east-west- or east-northeast-striking faults are of Silurian ages (40Ar/39Ar age 429 Ma). This group includes the Qimen-Shexian fault and the Jiangwang-Jiekou ductile shear belt. They represent a major tectonic boundary in the basement because the two sides of the fault have clear dissimilarities. The third group of faults is north-northeast striking, having formed since the early-middle Triassic with 40Ar/39Ar ages of 230-254 Ma. They form a fault belt starting from Yiyang in northern Jiangxi and connect with the Wucheng as well as the Ningguo-Jixi faults. This fault belt is a key fault-magmatic belt controlling the formation of Jurassic-Cretaceous red basins, ore distribution, magmatic activity, and mineralization. When it reactivated during the late Cretaceous, the belt behaved as a series of reverse faults from southeast to northwest and composed the fourth fault group. Therefore, classifying the Wan-Zhe-Gan fault zone into four fault groups will help in the analysis of the tectonic evolution of the eastern segment of the Jiangnan orogen since the Neoproterozoic era. 展开更多
关键词 The Wan-Zhe-Gan fault zone changes of orientations different evolution stages 40Ar/39Ar geochronology the border region of Zhejiang Jiangxi and Anhui Provinces
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AERODYNAMIC OPTIMIZATION DESIGN OF LOW ASPECT RATIO TRANSONIC TURBINE STAGE 被引量:2
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作者 SONG Liming LI Jun FENG Zhenping 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第4期500-504,共5页
The advanced optimization method named as adaptive range differential evolution (ARDE) is developed. The optimization performance of ARDE is demonstrated using a typical mathematical test and compared with the stand... The advanced optimization method named as adaptive range differential evolution (ARDE) is developed. The optimization performance of ARDE is demonstrated using a typical mathematical test and compared with the standard genetic algorithm and differential evolution. Combined with parallel ARDE, surface modeling method and Navier-Stokes solution, a new automatic aerodynamic optimization method is presented. A low aspect ratio transonic turbine stage is optimized for the maximization of the isentropic efficiency with forty-one design variables in total. The coarse-grained parallel strategy is applied to accelerate the design process using 15 CPUs. The isentropic efficiency of the optimum design is 1.6% higher than that of the reference design. The aerodynamic performance of the optimal design is much better than that of the reference design. 展开更多
关键词 Turbine stage Adaptive range differential evolution (ARDE)Aerodynamic optimization Coarse-grained parallel strategy
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Gas generation from coal: taking Jurassic coal in the Minhe Basin as an example
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作者 Deliang Fu Guosheng Xu +4 位作者 Li Ma Fu Yang Dan He Zhonghui Duan Yu Ma 《International Journal of Coal Science & Technology》 EI 2020年第3期611-622,共12页
The gas generation features of coals at different maturities were studied by the anhydrous pyrolysis of Jurassic coal from the Minhe Basin in sealed gold tubes at 50 MPa.The gas component yields(C1,C2,C3,i-C4,n-C4,i-C... The gas generation features of coals at different maturities were studied by the anhydrous pyrolysis of Jurassic coal from the Minhe Basin in sealed gold tubes at 50 MPa.The gas component yields(C1,C2,C3,i-C4,n-C4,i-C5,n-C5,and CO2);theδ13C of C1,C2,C3,and CO2;and the mass of the liquid hydrocarbons(C6+)were measured.On the basis of these data,the stage changes ofδ13C1,δ13C2,δ13C3,andδ13CO2 were calculated.The diagrams ofδ13C1–δ13C2 vs ln(C1/C2)andδ13C2–δ13C1 vsδ13C3–δ13C2 were used to evaluate the gas generation features of the coal maturity stages.At the high maturity evolution stage(T>527.6°C at 2°C/h),the stage change ofδ13C1 and the CH4 yield are much higher than that of CO2,suggesting that high maturity coal could still generate methane.When T<455°C,CO2 is generated by breaking bonds between carbons and heteroatoms.The reaction between different sources of coke and water may be the reason for the complicated stage change inδ13CCO2 when the temperature was higher than 455°C.With increasing pyrolysis temperature,δ13C1–δ13C2 vs ln(C1/C2)has four evolution stages corresponding to the early stage of breaking bonds between carbon and hetero atoms,the later stage of breaking bonds between carbon and hetero atoms,the cracking of C6+and coal demethylation,and the cracking of C2–5.Theδ13C2–δ13C1 vsδ13C3–δ13C2 has three evolution stages corresponding to the breaking bonds between carbon and hetero atoms,demethylation and cracking of C6+,and cracking of C2–5. 展开更多
关键词 Jurassic coal PYROLYSIS Gas generation δ13C Stage evolution
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Dynamic mechanism and present situation of rural settlement evolution in China 被引量:67
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作者 ZHOU Guohua HE Yanhua +3 位作者 TANG Chengli YU Tao XIAO Guozhen ZHONG Ting 《Journal of Geographical Sciences》 SCIE CSCD 2013年第3期513-524,共12页
This paper provides a detailed analysis of the factors influencing the evolution of rural settlements, including natural environmental constraints, infrastructure, regional cultural inheritance and integration, urbani... This paper provides a detailed analysis of the factors influencing the evolution of rural settlements, including natural environmental constraints, infrastructure, regional cultural inheritance and integration, urbanization and rural industrial transformation, land use refor- mation and innovation, rural household behavior conversion, macro-control policy factors, and so on. Based on differences between the ways and degree of effect on rural settlement evolution, these factors are classified into basic factors, new-type factors and mutation factors The drive of basic factors mainly focuses on the traditional inheritance of rural settlements, the new-type factors mainly affect rural settlement transition, and the mutation factors may bring about sudden changes. All these factors constitute a "three-wheel" driving mechanism for the evolution of rural settlements, and shape three typical driver paths: slow smooth path under the basic factors, new path to rapid development under the new-type factors, and the sudden change path under the mutation factors. The paper also investigates the overall situation of rural settlement evolution in the aspects of settlement system, settlement scale, settlement morphology, settlement function, settlement culture, settlement environment, etc. The general process of rural settlement evolution is divided into four stages: initial, transi- tional, developmental, and mature stages. 展开更多
关键词 rural settlements evolution evolution stage dynamic mechanism China
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Tectonic Evolution and Hydrocarbon Potential in Northern Area of the South Yellow Sea 被引量:6
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作者 姚永坚 陈春峰 +3 位作者 冯志强 张拭颖 郝天珧 万荣胜 《Journal of Earth Science》 SCIE CAS CSCD 2010年第1期71-82,共12页
The northern area of the South Yellow Sea, located in the offshore region of China, resulted from the continental-continental collision orogeny during the Mesozoic and can be divided into four stages in terms of tecto... The northern area of the South Yellow Sea, located in the offshore region of China, resulted from the continental-continental collision orogeny during the Mesozoic and can be divided into four stages in terms of tectonic evolution: (1) pre-orogenic passive continental margin stage (Z-T2); (2) foreland basin stage corresponding with the late phase of the Sulu (苏鲁) orogeny (J3-K); (3) post-orogenic intracontinental rifted basin stage (K2t-E); and (4) regional subsidence and coverage stage (N-Q). Based on detailed investigation and study of the intracontinental rifted basin, hydrocar- bon source rocks of Late Cretaceous Taizhou (泰州) Formation distributed well in the basin, and four reservoir-cap combinations as well as numerous trap structures were found. As a result, the geological conditions would be excellent for reservoir formation in the basin, and the oil resource amount is estimated at about 20×10^8 t, which makes the basin a major target for hydrocarbon exploration in the South Yellow Sea. 展开更多
关键词 northern area of the South Yellow Sea tectonic evolution stage OROGENY source- reservoir-cap combination hydrocarbon exploration potential.
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The evolution of investments decision mode in China's telecommunication 被引量:2
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作者 ZHANG Ai-hua ZHAO Lian-qiang SHU Hua-ying 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2007年第1期122-128,共7页
This essay analyzes the data of Chinese telecommunication market, telecommunication investments and investment benefits over the past 20 years. On the basis of these data, the essay reviews Chinese changing telecommun... This essay analyzes the data of Chinese telecommunication market, telecommunication investments and investment benefits over the past 20 years. On the basis of these data, the essay reviews Chinese changing telecommunication policies and discusses the major events in the course of China's telecommunication development. It is argued that telecommunication policies, regime backgrounds and market demand characteristics have a significant impact on investment decision mode in telecommunication industry. The evolution of network investments decision mode in China's telecommunication has corresponded to the transformation of these key factors. Considering the special events in the development of Chinese telecommunication as divisions, the essay discusses three stages of the evolution of investments decision mode in China's tel With the firm environment and problems that Chinese telecommunication operators have been facing since 2000 analyzed, it is demonstrated that Chinese telecommunication operators should change their mode of investment decision into the "profit-oriented investment decision mode" in order to achieve a high growth performance in the capital market,. This investment decision mode will result in increase of the investment profit with limited investment capital. The main procedure of profit-oriented investment decision mode is set out, which is abstracted to a mathematical model eventually. 展开更多
关键词 China's telecommunication investment decision mode evolution stage key factor investment profit
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Thermal simulation experiment of organic matter-rich shale and implication for organic pore formation and evolution 被引量:5
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作者 Zhongliang Ma Lunju Zheng +2 位作者 Xuhui Xu Fang Bao Xiaolu Yu 《Petroleum Research》 2017年第4期347-354,共8页
A thermal simulation experiment of diagenesis,hydrocarbon generation and evolution of the organic matter-rich shale was carried out to investigate formation and evolution of organic pores under the constraint from imm... A thermal simulation experiment of diagenesis,hydrocarbon generation and evolution of the organic matter-rich shale was carried out to investigate formation and evolution of organic pores under the constraint from immature,low mature,mature,high mature to overmature geological conditions.The argon ion polishingefield emission scanning electron microscope was used to analyze microscopic features of original samples and simulated samples of various evolution stages.Results showed organic pores could be formed during hydrocarbon generation from biochemical and hypothermal processes in the immature and low mature stages,and the shale shallow-buried depth might be favorable for preservation of organic pores;the generation and evolution of organic pores were of heterogeneity,and the maturity was not a decisive factor which controlled formation and development of organic pores,while the difference in physiochemical structure of organic matter played an important role in formation and evolution of organic pores;the organic pore development was obviously related with the retained oil,and the organic pores formed in the oil generation stage were easily filled by pyrolysis asphalt;organic contraction fractures/organic marginal pores might be important storage spaces for shale gas occurrence,and their development was mainly controlled by the physiochemical structure and evolution degree of organic matters when the chemical adsorbed organic matter was converted into the physical adsorbed organic matter and the free organic matter. 展开更多
关键词 Thermal simulation experiment Organic pores Thermal evolution stage HETEROGENEITY Plane porosity Retained oil SHALE
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Adaptive Walking Control of Biped Robots Using Online Trajectory Genera- tion Method Based on Neural Oscillators 被引量:6
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作者 Chengju Liu Danwei Wang +1 位作者 Erik David Goodman Qijun Chen 《Journal of Bionic Engineering》 SCIE EI CSCD 2016年第4期572-584,共13页
This work concerns biped adaptive walking control on irregular terrains with online trajectory generation. A new trajectory generation method is proposed based on two neural networks. One oscillatory network is design... This work concerns biped adaptive walking control on irregular terrains with online trajectory generation. A new trajectory generation method is proposed based on two neural networks. One oscillatory network is designed to generate foot trajectory, and another set of neural oscillators can generate the trajectory of Center of Mass (CoM) online. Using a motion engine, the characteristics of the workspace are mapped to the joint space. The entraining property of the neural oscillators is exploited for adaptive walking in the absence of a priori knowledge of walking conditions. Sensory feedback is applied to modify the gen- erated trajectories online to improve the walking quality. Furthermore, a staged evolutionary algorithm is developed to tune system parameters to improve walking performance. The developed control strategy is tested using a humanoid robot on ir- regular terrains. The experiments verify the success of the presented strategy. The biped robot can walk on irregular terrains with varying slopes, unknown bumps and stairs through autonomous adjustment of its walking patterns. 展开更多
关键词 biped robot adaptive walking neural oscillator trajectory generation staged evolution algorithm
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