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Chinese Geographical Science 2002年第3期12卷 212-217页

作者： ZHU Xi-gang,ZHANG Jing-xiang,CHEN Hu (Department of Urban and Resources Sciences,Nanjing University,Nanjin g 210093,P.R.China,) Department of Urban and Resources Sciences Nanjing University Nanjing P. R. China

In rapid socio-economic developme nt,the process of concentration and dispersal of various elements tends to be more dramatic,tremendously in fluencing the shaping and transform ation of the space in metropolitan *** of spatial concentration and decent ralization has thus become a basic me thod in examining metropolitan spatial *** this research,three elements were selected as the essential indicato rs of the process:demographic density distribu-tion,employment density distribut ion and business office *** of these elements in Nanji ng City was exam-ined *** Nanjing City c ould be regarded as a representative of metropolitan areas in China,its s ituation large-ly suggestes the general characteristics in similar areas of *** based on the investigation of Nanji ng City,four general implications were highligh ***,metropolitan areas inChina are in a violentprocess and shift of spatialconcentra-tion and ***,from now to at least the near future,c oncentration will continue to be the central ***,the landscape of metrop olitan areas basically exhibits a dual structure *** gap in en vironmental and ecological qualities among different districts will continue for a l ong ***,Central Business District(CBD)is playing an important role in helpi ng to convert the traditionally single-centered city structure into a polycentric one.

关键词： concentration decentralization dynamic mechanism nanjing metropolis

Driving forces and their relative contributions to hydrocarbon expulsion from deep source rocks: A case of the Cambrian source rocks in the Tarim Basin

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Petroleum Science 2023年第1期20卷 20-33页

作者： Bo Pang Jun-Qing Chen Xiong-Qi Pang Tao Hu Yue Sheng State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China College of Geosciences China University of PetroleumBeijing102249China College of Science China University of PetroleumBeijing102249China Laboratory of Optical Detection Technology for Oil and Gas China University of PetroleumBeijing102249China Basic Research Center for Energy Interdisciplinary China University of PetroleumBeijing102249China CNPC Economics&Technology Research Institute Beijing100029China

To thoroughly understand the dynamic mechanism of hydrocarbon expulsion from deep source rocks,in this study,five types of hydrocarbon expulsion dynamics(thermal expansion,hydrocarbon diffusion,compaction,product volume expansion,and capillary pressure difference(CPD))are studied.A model is proposed herein to evaluate the relative contribution of different dynamics for hydrocarbon expulsion using the principle of mass balance,and the model has been applied to the Cambrian source rocks in the Tarim *** evaluation results show that during hydrocarbon expulsion from the source rocks,the relative contribution of CPD is the largest(>50%),followed by compaction(10%-40%),product volume expansion(5%-30%),and thermal expansion(2%-20%).The relative contribution of diffusion to hydrocarbon expulsion is minimal(dynamics to the process:the first stage is dominated by compaction and diffusion to expel hydrocarbons,the second stage is dominated by product volume expansion and CPD,and the third stage is dominated by product volume expansion and *** research offers new insights into hydrocarbon exploration in tight oil and gas reservoirs.

关键词： Driving force dynamic mechanism Hydrocarbon expulsion Deep oil and gas exploration Tarim Basin

Recent tectonic stress field zoning in Sichuan-Yunnan region and its dynamic interest

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Acta Seismologica Sinica(English Edition) 2006年第5期19卷 485-496页

作者：崔效锋谢富仁张红艳 Institute of Crustal dynamics China Earthquake Administration

In this paper, we have carefully determined the stress zones in the Sichuan-Yunnan region with reference to the in-situ stress data of hydraulic fracturing and the inverted fault slip data by using the step-by-step convergence method for stress zoning based on focal mechanism solutions. The results indicate that the tectonic stress field in the Sichuan-Yunnan region is divided into 3 stress zones by 2 approximately parallel NNW-trending stress transition belts. The area between the 2 belts is the Sichuan-Yunnan stress zone where the maximum principal stress σ1 is just in the NNW direction. The eastern boundary of Sichuan-Yunnan stress zone （the eastern stress transition belt） is basically consistent with the eastern boundary of Sichuan-Yunnan rhombic block. The western boundary of Sichuan-Yunnan stress zone （the western stress transition belt） is not totally consistent with the western boundary of Sichuan-Yunnan rhombic block. The northern segment of the western stress transition belt extends basically along the Jinshajiang fault and accords with the western boundary of Sichuan-Yunnan rhombic block, while its southern segment does not extend along the southwestern boundary of the rhombic block, i.e., Honghe fault and converge with the eastern stress transition belt, but stretches continuously in the NNW direction and accords with the Yingpanshan fault. We therefore consider that under the combined influence from the northward motion of India Plate, the southeastward shift of east Qinghai-Xizang Plateau and the strong obstruction of South China block, the tectonic stress field in the Sichuan-Yunnan region might not be totally controlled by the previous tectonic frame and new stress transition belt may have possibly formed.

关键词： Sichuan-Yunnan area stress field stress zoning dynamic mechanism

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跨域环境治理的组合式协同机制与运作逻辑

Sedimentary filling and sequence structure dominated by T-R cycles of the Nenjiang Formation in the Songliao Basin

生态环境与保护 2024年第3期

作者：杨旭高光涵

在迈向中国式现代化的伟大征程中，环境治理现代化是中国式现代化的治理回应与检证载体。以“环境治理现代化”表征的这种中国式现代化是对现代性本身的再现代化，需要重新去认识和把握跨域环境治理模式的“现代”属性。从环境污染正在... 详细信息

在迈向中国式现代化的伟大征程中，环境治理现代化是中国式现代化的治理回应与检证载体。以“环境治理现代化”表征的这种中国式现代化是对现代性本身的再现代化，需要重新去认识和把握跨域环境治理模式的“现代”属性。从环境污染正在经历的由局部向广域转变的解域化过程来看，跨区域环境协同治理是多辖区间联结与互动的动态演化过程。既有研究已从多层面和多维度视域构建了跨域环境协同治理的理论框架，对于回答协同的应然状态以及如何锻造良好的协同秩序进行了叙事性再现和动态关联考察，但就协同进程中动力机制对协同结果的塑造作用探讨不乏“意犹未尽”之处。基于长三角一体化示范区环境协同治理，构建“理念-制度-实践”理论图式，并从触发机制、驱动机制和行动机制3个维度探索了开启跨域生态合作动力来源的机制之钥。研究发现，长三角一体化示范区在环境治理中的协同模式是典型的组合式协同，存在以系统协同牵引绿色协同的发展倾向，更具有不变体制变机制的内在属性，此种模式是长三角一体化示范区在激励约束与功能分割双重作用下的理性择定。“组合式协同”在应对长三角一体化示范区跨界环境污染问题上能够获得有效的合法性与合宪性回馈，并因其秉持共生、共进以及共享逻辑而取得持续性的协同效应。

关键词：生态文明环境治理组合式协同动力机制内在逻辑长三角一体化 ecological civilization environmental governance combined collaboration dynamic mechanism internal logic Yangtze River Delta integration

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Science China Earth Sciences 2014年第12期57卷 278-296页

作者： ZHANG ChenChen ZHANG Shun WEI Wei WU ChaoDong LIANG JiangPing NIU Wen DU JinXia FU XiuLi CUI KunNing WANG Chao WANG Hui School of Earth and Space Science Peking University Research Institute of Petroleum Exploration and Development PetroChina Daqing Oil Field Company

The Nenjiang Formation in the Songliao Basin is a symmetrical sequence of progradation-retrogradation,and is formed in the transgression cycle and regression cycle(T-R cycles)of the base level of *** analyzed the drilling,well logging,core data,and seismic profiles of basin level,and by using the sequence stratigraphy,identified one secondary sequence boundary,two third-order sequence boundaries,and eight fourth-order sequence boundaries in the Nenjiang *** eleven sequence boundaries can be divided into structural unconformity,depositional unconformity,flooding surface,and forced regression *** the Nenjiang Formation can be subdivided into one secondary sequence,three third-order sequences,and ten fourth-order *** have restored the sedimentary filling evolution within the stratigraphic framework of fourth-order sequences in the Nenjiang *** sedimentary period of the first member of the Nenjiang Formation was corresponded to the global transgression period,which is also the development period of transgression cycle(T cycle),when the lake basin had the largest scope and deepest sedimentary water,the SB07(the maximum flooding surface)was formed on the top of strata during this period;covering above the SB07,there developed a set of condensation layer-oil shale,which is distributed in the whole basin and is the important source bed and regional ***,a retrogradation sequence was formed in the T cycle of the first member of the Nenjiang Formation,characterized by the retrograding delta at a low *** delta has a giant front,a small plain,and many underwater distributary ***,large gravity flow channels and sublacustrine fans are developed in the front of the *** the depositional period of the second member of the Nenjiang Formation,the R cycle began to develop due to the compression of the pacific tectonic domain;the source direction rotated 90°along with the eastern uplifting of

关键词： transgressive-regressive cycles sedimentary evolution dynamic mechanism Songliao Basin Nenjiang Formation

Fluid Mud Measurement and Siltation Analysis in A Trial Excavated Channel in the Approach Channel of the Xiangshan Port

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China Ocean Engineering 2020年第3期34卷 421-431页

作者： DING Jian HU Guo-dong WANG Zhen-xiang SHI Jian WU De-an Key Laboratory of Coastal Disasters and Defence Ministry of EducationHohai UniversityNanjing 210098China Yangtze River Estuary Investigation Bureau of Hydrology and Water Resource Shanghai 200136China

In order to clarify the distribution and variation of silt and fluid mud in the Waiganmen shallow section of the 50000-ton intake channel of the Xiangshan Port,and to understand the influence of the channel excavation on the surrounding flow conditions and the strength of the backsilting,especially the impact of typhoon on the sudden silting of the channel,so as to demonstrate the feasibility and stability of the channel *** fluid mud,hydraulic,sediment and topographic measurements were carried out in the study area,and the thickness of the fluid mud layers,tidal current,sediment and topographic data were ***-frequency sounder,gamma-ray densitometer and SILAS navigational fluid mud measurement system were used to monitor the fluid mud,and the results were compared and *** adaptability and accuracy of the three methods were *** SILAS navigational continuous density measurement system and gamma-ray fixed-point fluid mud measurement are used to detect the density,thickness and variation of the fluid mud *** on the hydrological observation data,the process of erosion and deposition in excavation channel and its influence mechanism are analyzed,and the distribution characteristics and evolution law of siltation in engineering area are given in the form of empirical *** research shows that the super typhoon can produce large siltation,which results in sudden siltation of the *** tidal current is the main dynamic factor of the change of erosion and siltation of the excavation *** the influence of reciprocating tidal current and excavation topography,the trial excavation trench is silted on the *** is fluid mud in the monitoring area of the trench,and the distribution of fluid mud is different in *** thickness of the fluid mud at the bottom of the trench is generally larger than that outside the trench and the slope of the trench,and the siltation of the trench tends to be *** re

关键词： excavation trench fluid mud backsilting measurement tidal current dynamic mechanism

Study on the effect of focal position change on the expansion velocity and propagation mechanism of plasma generated by millisecond pulsed laser-induced fused silica

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Plasma Science and Technology 2023年第3期25卷 171-180页

作者：王立雪蔡继兴 Jilin Key Laboratory of Solid-state Laser Technology and Application School of PhysicsChangchun University of Science and TechnologyChangchun 130022People’s Republic of China

In this work, by controlling the positional relationship between the target and the focal point, the surface damage, shock wave phenomenon and propagation mechanism involved in the plasma generation of fused silica by millisecond pulsed laser irradiation at different focal positions were studied. Laser energy is an important experimental variable. The dynamic process of plasma was detected by optical shadow method, and the influence of surface film damage on plasma propagation and the propagation mechanism at different focal positions were discussed. The study found that the plasma induced by the pulsed laser at the focus position within 0–20 μs exploded, the micro-droplets formed around 20 μs. At the same time, a shock wave is formed by the compressed air, the micro-droplets are compressed under the action of the shock wave recoil pressure, and the micro-droplets channel phenomenon is observed in the micro-droplets. The peak velocities of plasma and combustion wave appear earlier in the pre-focus position than in the post-focus position. This research provides a reference for the field of laser processing using fused silica as the substrate.

关键词： relationship of different focal positions plasma combustion wave shock wave dynamic mechanism damage morphology

Determination of H^+ diffusion coefficient in the course of H^+ response of a W/WO_3 pH electrode

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Rare Metals 2005年第4期24卷 351-357页

作者： CHEN Dongchu FU Zhaoyang ZHENG Jiashen College of Mechanical Engineering South China University of Technology Guangzhou 510640 China School of Science Foshan University Foshan 528000 China Chemistry Department Huazhong University of Science and Technology Wuhan 430074 China

A WAVO3 pH electrode was prepared by a method of sol-gel. In order to study the H^＋ response dynamic mechanism, the electrochemical impedance spectroscopy （EIS） experiment was conducted. It was found that the H^＋ response course is controlled by the H^＋ diffusion from the solution to the WO3 film, based on the analysis of EIS spectra. The EIS and potential step method were used to determinate the H＋ diffusion coefficient （D） in the course of H^＋ response of this WAVO3 electrode, and the values of D calculated by these two method correspond very well, which all are about 10^-19cm^2/s The imposed different potential steps make little effect on the calculation of H^＋ diffusion coefficient, and it was found that the limiting Cottrell equation of short elapsed time fits well to the current transient caused by a potential step, based on the analysis of the time constant.

关键词： pH electrode diffusion coefficient dynamic mechanism tungsten oxide sol-gel

Morphodynamic evolution of the Xiaoqing River mouth:a Huanghe River-derived mixed energy estuary

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Chinese Journal of Oceanology and Limnology 2012年第5期30卷 889-904页

作者：黄海军刘艳霞丘仲锋 Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of Sciences Nanjing University of Information and Technology

In an estuary,tidal,wave and other marine powers interact with the coast in different ways and affect estuary morphology as well as its *** the Huanghe(Yellow) River estuaries and nearby delta,there are many small sediment-affected estuaries with a unique morphology,such as the Xiaoqing River *** this study,we investigated the special evolution and genetic mechanism of the Xiaoqing River estuary by analyzing graphic and image data with a numerical simulation *** results show that NE and NE-E tide waves are the main driving force for sandbar *** shoals have originated from huge amounts of sediment from the Huanghe River,with consequent deposition at the Xiaoqing River *** lateral suspended sediments beyond the river mouth move *** takes place on the northern shoreline near the river mouth whereas erosion occurs in the *** deposits come mainly from scouring of the shallow seabed on the northern side of the *** surges speed up deposition in the *** of the sediment shoals has occurred in two steps involving the processes of growth and further southward *** the southward shift increases the river curvature and length,the general eastward orientation of the estuary is unlikely to *** on the adjacent shorelines do not affect the development of the sediment *** study presents a morphodynamic evolutionary model for the Xiaoqing River estuary,with a long-term series cycle,within which a relatively short cycle occurs.

关键词： estuary sediment shoal numerical simulation dynamic mechanism mixed energy

The influencing factors of urban land expansion in Changsha

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Journal of Geographical Sciences 2007年第4期17卷 487-499页

作者： ZHOU Guohua HE Yanhua College of Science of Resource ＆ Environment Science Hunan Normal University Changsha 410081 China

This research systematically analyses land-use map of Changsha city in different periods of time. The spatial form and structural evolution was analysed by studying indices such as city land-use structure proportion, expansion intensity, economic flexibility, population flexibility, changing compactness index and so on. The dynamic mechanism of urban land expansion has been discussed by integrating the regional social economy development situation and many aspects such as the physiographical surrounding, population and economic development, traffic infrastructure, planning and regional development tactic and system innovation. The research indicates that the urban land expansion speed and intensity have steadily increased in Changsha from 1949 to 2004. The expansion form has been from a single external expansion to a combination form of external and internal expansion, from a circular or linear continuous form to a blocky or agglomeration shape. Overall, the urban land expansion of Changsha city is a phasic, diversified and complex process. And no matter what the stage is, it is an organic system containing multiple speed, pattern and shape, which are driven by multiple impetuses. The dominant feature at different stages was highlighted because of the balance and fluctuation between different forces, and the existing urban land border and shape have resulted from the joint efforts of these phasic forces.

关键词： Changsha urban land expansion influencing factors dynamic mechanism