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New Rural Community Construction or Retention Development:A Comparative Analysis of Rural Settlement Transition Mechanism in Plain Agriculture Area of China Based on Actor Network Theory
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作者 QU Yanbo DONG Xiaozhen +1 位作者 MA Wenqiu ZHAO Weiying 《Chinese Geographical Science》 SCIE CSCD 2024年第3期436-452,共17页
It is an important way to realize rural revitalization and sustainable development to guide rural settlement transition(RST)in an appropriate way.This paper uses actor network theory(ANT)to construct a theoretical fra... It is an important way to realize rural revitalization and sustainable development to guide rural settlement transition(RST)in an appropriate way.This paper uses actor network theory(ANT)to construct a theoretical framework for the study of RST.Taking two typical villages with different transition paths in rural areas of North China Plain as examples,this paper reveals the mechanism of RST and makes a comparative analysis.The results show that:1)after identifying problems and obligatory passage point,key actors recruit heterogeneous actors into the actor network by entrusting them with common interests,and realize RST under the system operation.2)Rural settlements under different transition paths have similarities in the problems to be solved,collective actions and policy factors,but there are differences in the transition process,mechanism and effect.The actor network and mechanism of RST through the path of new rural community construction are more complex and the transition effect is more thorough.In contrast,the degree of RST of retention development path is limited if there is no resource and location advantage.3)Based on the applicable conditions of different paths,this paper designs a logical framework of‘Situation-Structure-Behavior-Result’to scientifically guide the identification of RST paths under the background of rural revitalization. 展开更多
关键词 rural settlement transition(RST) actor network theory(ANT) transition path transition mechanism plain area China
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Characteristics and influencing mechanisms of production-living-ecological space dynamics in the Three Gorges Reservoir Area(TGRA),Chongqing,China
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作者 ZHU Xinyi GAO Jinlong 《Regional Sustainability》 2024年第2期49-62,共14页
The Three Gorges Reservoir Area(TGRA)is an important ecological barrier in the Yangtze River Basin,China.Therefore,it is of great importance to understand the spatio-temporal variation and the driving factors of produ... The Three Gorges Reservoir Area(TGRA)is an important ecological barrier in the Yangtze River Basin,China.Therefore,it is of great importance to understand the spatio-temporal variation and the driving factors of production-living-ecological spaces for sustainable and high-quality development in the TGRA.This study investigated the dynamic variation of production-living-ecological spaces in the TGRA by employing land use data in 2000,2005,2010,2015,and 2018,and detected the influencing factors by using the Geographic detector(GeoDetector).Results implied that the structure and dynamic trajectories of production-living-ecological spaces in the TGRA varied in both horizontal and vertical directions,and the study area was dominated by ecological space.A spatial orientation towards the northeast was detected in the evolution of production-living-ecological spaces during 2000-2018.In terms of quantity,the transition from ecological space(grassland and woodland)to agriculture land accounted for the largest proportion from 2000 to 2018.However,the reverse transition from agriculture land to ecological space has increased since 2000 with the efforts of“Grain for Green”.In terms of temporal scale,there was a fluctuating trend in production space with the continuous expansion of living space,while ecological space showed an inverted U-shaped trend during 2000-2018.The dynamic pattern of production-living-ecological spaces in the TGRA was influenced by both physical and socio-economic variables as basic determinants and dominant driving factors,respectively.Finally,the harmonization and protection of production-living-ecological spaces still require policy-makers’efforts.This work may have potential in advancing our understanding about land use conflicts,and provide a reference for rational layout of spatial functions and the realization of sustainable development in the TGRA. 展开更多
关键词 Production-living-ecological spaces Functional transition three Gorges Reservoir area(TGRA) Physical and socio-economic variables Yangtze River
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Driving Analysis on Ecological Security in Vulnerable Transition Areas of Mountain and Plain 被引量:1
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作者 刘欣 赵艳霞 +2 位作者 秦彦杰 张金英 武爱彬 《Agricultural Science & Technology》 CAS 2013年第3期433-435,共3页
[Objective] This study aimed to investigate the driving mechanism of eco- logical security in vulnerable areas in mountain and plain. [Method] The ecological security evaluation index system of Lincheng County was est... [Objective] This study aimed to investigate the driving mechanism of eco- logical security in vulnerable areas in mountain and plain. [Method] The ecological security evaluation index system of Lincheng County was established using PSR model. Driving mechanism was analyzed in total system and subsystems respectively by the principal components. The ecological safety driving factor was calculated through the total system and subsystem respectively. And the intersection was adopt- ed as dominant driving factor. [Result] A total of 10 indices including density index of rivers, land degradation index, farmland drought and flood insurance yield, human in- terference index, population density, the natural population growth rate, per capita GDP, the R&D funds spending accounts for the proportion of GDP, laborer by edu- cation degree and three industry accounted for the proportion of GDP, are the domi- nant driving factors of the regional ecological security. [Conclusion] This study will pro- vide reasonable and feasible advice for the benign development of the area. 展开更多
关键词 Ecological security Driving force transition areas of mountains and plains
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Planning and construction of Xiong’an New Area(city of over 5 million people):Contributions of China’s geologists and urban geology
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作者 Bo Han Zhen Ma +9 位作者 Liang-jun Lin Hong-wei Liu Yi-hang Gao Yu-bo Xia Hai-tao Li Xu Guo Feng Ma Yu-shan Wang Ya-long Zhou Hong-qiang Li 《China Geology》 CAS CSCD 2024年第3期382-408,共27页
China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and t... China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and to expedite the coordinated development of the Beijing-Tianjin-Hebei region.From 2017 to 2021,the China Geological Survey(CGS)took the lead in multi-factor urban geological surveys involving space,resources,environments,and disasters according to the general requirements of“global vision,international standards,distinctive Chinese features,and future-oriented goals”in Xiong’an New Area,identifying the engineering geologic conditions and geologic environmental challenges of this area.The achievements also include a 3D engineering geological structure model for the whole area,along with“one city proper and five clusters”,insights into the ecology and the background endowment of natural resources like land,geothermal resources,groundwater,and wetland of the area before engineering construction,a comprehensive monitoring network of resources and environments in the area,and the“Transparent Xiong’an”geological information platform that is open,shared,dynamically updated,and three-dimensionally visualized.China’s geologists and urban geology have played a significant role in the urban planning and construction of Xiong’an New Area,providing whole-process geological solutions for urban planning,construction,operation and management.The future urban construction of Xiong’an New Area will necessitate the theoretical and technical support of earth system science(ESS)from various aspects,and the purpose is to enhance the resilience of the new type of city and to provide support for the green,low-carbon,and sustainable development of this area. 展开更多
关键词 Low Carbon New City Planning and construction Land Geothermal resources Groundwater Wetland Underground space Geologic disasters Site stability natural resource Ecosystem Geological safety Transparent Xiong’an Resilient city Xiong’an New area
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Research on the Impact and Strategies of Rail Transit Network Integration in the Context of Metropolitan Area Development:A Case Study of the Wuhan Metropolitan Area
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作者 Xiaorong Wang Rong Li 《Proceedings of Business and Economic Studies》 2024年第5期73-80,共8页
The metropolitan area is one of the key focal points in the construction and development of China’s new urbanization.Urban integration is an emerging trend in metropolitan areas.This paper explores the traffic demand... The metropolitan area is one of the key focal points in the construction and development of China’s new urbanization.Urban integration is an emerging trend in metropolitan areas.This paper explores the traffic demand characteristics and economic aspects of rail transit within metropolitan regions and argues that the construction of an integrated urban rail transit network is an effective approach to support their development.Rail transit in metropolitan areas offers both technical and economic advantages,improving the efficiency of time and space resource utilization,fostering economic cooperation,and ultimately contributing to an integrated development model.However,the integration of rail transit networks faces several challenges,including road network planning,technical standards,and operational organization.Using the Wuhan metropolitan area as a case study,this paper analyzes the challenges of rail transit network integration and proposes strategic solutions for development. 展开更多
关键词 Rail transit Metropolitan area Rail network integration URBANIZATION
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Ecological and habitat ranges of orchids in the northernmost regions of their distribution areas:A case study from Ural Mountains,Russia
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作者 Irina A.Kirillova Yuriy A.Dubrovskiy +1 位作者 Svetlana V.Degteva Alexander B.Novakovskiy 《Plant Diversity》 SCIE CAS CSCD 2023年第2期211-218,共8页
The Orchidaceae,which is one of the most interesting families of angiosperms,contains a large number of rare species.Despite their acknowledged importance,little attention has been paid to the study of orchids distrib... The Orchidaceae,which is one of the most interesting families of angiosperms,contains a large number of rare species.Despite their acknowledged importance,little attention has been paid to the study of orchids distributed in northern territories.In this study,we determined the syntaxonomical diversity and ecological parameters of orchid habitats in two of Europe's largest protected areas,the Pechoro-Ilychsky Reserve and the Yugyd Va National Park(northeastern European Russia),and then compared our findings to those in other parts of orchid distribution ranges.For this purpose,we studied 345 descriptions of plant communities(releves) containing species from Orchidaceae and defined habitat parameters using Ellenberg indicator values with the community weight mean approach,nonmetric multidimensional scaling(NMS),and relative niche width.We found that orchids were distributed in eight habitat types and 97 plant associations.The largest number of orchid species is found in forest communities.Half of the orchid species under study occur in the mires and rock habitats with open vegetation.Several orchids consistently occur in areas disturbed by human activity.In addition,our study indicates that the main drivers of orchid distribution across the vegetation types are light and soil nitrogen.Our analysis of the ecological parameters of orchid habitats indicates that some orchid species can be classified as habitat specialists that are confined to a relatively narrow ecological niche in the Urals(e.g.,Goodyera repens,Cypripedium guttatum and Dactylorhiza maculata).Several other species(e.g.Neottia cordata and Dactylorhiza fuchsia) grow under diverse ecological parameters. 展开更多
关键词 ORCHIDACEAE Plant communities Nature protected areas Community weight mean Illumination Moisture
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Geological conditions of natural gas accumulation and new exploration areas in the Mesoproterozoic to Lower Paleozoic of Ordos Basin, NW China 被引量:6
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作者 DU Jinhu LI Xiangbo +6 位作者 BAO Hongping XU Wanglin WANG Yating HUANG Junping WANG Hongbo WANYAN Rong WANG Jing 《Petroleum Exploration and Development》 2019年第5期866-882,共17页
Based on field outcrop investigation,interpretation and analysis of drilling and seismic data,and consulting on a large number of previous research results,the characteristics of ancient marine hydrocarbon source rock... Based on field outcrop investigation,interpretation and analysis of drilling and seismic data,and consulting on a large number of previous research results,the characteristics of ancient marine hydrocarbon source rocks,favorable reservoir facies belts,hydrocarbon migration direction and reservoir-forming law in the Ordos Basin have been studied from the viewpoints of North China Craton breakup and Qilian-Qinling oceanic basin opening and closing.Four main results are obtained:(1)Controlled by deep-water shelf-rift,there are three suites of source rocks in the Ordos Basin and its periphery:Mesoproterozoic,Lower Cambrian and Middle-Upper Ordovician.(2)Controlled by littoral environment,paleo-uplift and platform margin,four types of reservoirs are developed in the area:Mesoproterozoic-Lower Cambrian littoral shallow sea quartz sandstone,Middle-Upper Cambrian–Ordovician weathering crust and dolomitized reservoir,and Ordovician L-shape platform margin reef and beach bodies.(3)Reservoir-forming assemblages vary greatly in the study area,with"upper generation and lower storage"as the main pattern in the platform,followed by"self-generation and self-storage".There are both"upper generation and lower storage"and"self-generation and self-storage"in the platform margin zone.In addition,in the case of communication between deep-large faults and the Changchengian system paleo-rift trough,there may also exist a"lower generation and upper reservoir"combination between the platform and the margin.(4)There are four new exploration fields including Qingyang paleo-uplift pre-Carboniferous weathering crust,L-shape platform margin zone in southwestern margin of the basin,Ordovician subsalt assemblage in central and eastern parts of the basin,and Mesoproterozoic–Cambrian.Among them,pre-Carboniferous weathering crust and L-shape platform margin facies zone are more realistic replacement areas,and Ordovician subsalt assemblage and the Proterozoic-Cambrian have certain potential and are worth exploring. 展开更多
关键词 natural gas exploration area hydrocarbon ACCUMULATION geological conditions MESOPROTEROZOIC NEOPROTEROZOIC Lower PALEOZOIC ORDOS Basin
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Application of a New Qeneration of Geophonesto Improve Seismic Acquisitionin Onshore-offshore Transition Areas 被引量:1
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作者 吕公河 《Applied Geophysics》 SCIE CSCD 2005年第4期235-240,共6页
In this paper, we review the differences between velocity geophones (VG) and acceleration geophones (AG) and their effect on seismic signals acquired in onshore-offshore transition areas. We present a new generati... In this paper, we review the differences between velocity geophones (VG) and acceleration geophones (AG) and their effect on seismic signals acquired in onshore-offshore transition areas. We present a new generation of Land Piezoelectric Geophone (LPG) and analyze its performance. Our field experiments demonstrate that our new LPG can be used to substitute for VGs in order to eliminate phase, frequency and energy differences between different geophone systems commonlv used in transition areas. 展开更多
关键词 transition areas vibrate system land piezoelectric geophone frequency characteristics data acquisition
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Application of Variable Strategies in the Low-cost and Energy-saving Rural Residences in Transitional Areas 被引量:1
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作者 LU Meijun LIU Jingxia WANG Guixiu 《Journal of Landscape Research》 2012年第9期49-51,共3页
Changeful and complex rural family structure and climatic features of transitional areas in China make the application of variable strategy in energy-saving rural residence designs possible.Aiming at the low cost,seve... Changeful and complex rural family structure and climatic features of transitional areas in China make the application of variable strategy in energy-saving rural residence designs possible.Aiming at the low cost,several effective and reasonable variable strategies were proposed for the design of interior spaces,main bedroom,sunshine room,staircase,west wall,door and window design to satisfy changing structure of a family during different periods and their different thermo-technical requirements in winter and summer.In this way,thermal comfort of rural indoor spaces will be improved,more energy saved,useful experience and thoughts provided for the energy-saving residence design in cold regions and regions hot in summer and cold in winter. 展开更多
关键词 VARIABLE STRATEGIES transitional area RURAL RESIDENCE ENERGY-SAVING design Family structure CLIMATIC features
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Heterogeneity-diversity Relationships in Natural Areas of Yunnan,China 被引量:1
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作者 LIU Feng HU Jinming +1 位作者 YANG Feiling LI Xinwang 《Chinese Geographical Science》 SCIE CSCD 2021年第3期506-521,共16页
Understanding regional environmental heterogeneity(EH)and biodiversity relationships(heterogeneity-diversity relationships:HDRs)is the first step toward coupling environmental variables with biodiversity surrogates in... Understanding regional environmental heterogeneity(EH)and biodiversity relationships(heterogeneity-diversity relationships:HDRs)is the first step toward coupling environmental variables with biodiversity surrogates into regional systematic conservation planning.However,there is no universal method for determining regional HDRs that considers various environmental variables and biodiversity in different regions.This study selected 32 nature reserves as natural areas in Yunnan,China,to examine regional HDRs in Yunnan.We calculated 17 EH parameters(of soil,topography,and climate)and three(ecosystem,plant,and animal)biodiversity indices in the nature reserves.By examining the explanatory power of each EH parameter and area of the nature reserve,we identified the primary parameters and constructed an optimal model for each biodiversity index.The explanatory powers of these parameters varied for each biodiversity index,and those of climatic parameters were generally higher than soil and topographic heterogeneity ones.Heterogeneity of the temperature annual range,followed by area and heterogeneity of soil type,were important parameters for ecosystem diversity of Yunnan and the optimal model explained 56.9%.Plant diversity was explained 54.5%by its optimal model,consisting of heterogeneity of precipitation of the coldest quarter and annual precipitation.Heterogeneity of temperature annual range was important for animal diversity in Yunnan and explained 29.6%of its optimal model.This study suggests that EH parameters can be an effective surrogate for biodiversity,therefore,we suggested that the significance and role of climatically heterogeneous regions for the conservation of biodiversity in Yunnan should be further studied in the future. 展开更多
关键词 BIODIVERSITY environmental heterogeneity heterogeneity-diversity relationships(HDRs) natural areas Yunnan China
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Spatial Pattern and Development of Protected Areas in the North-south Transitional Zone of China 被引量:1
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作者 LI Xiang MA Beibei +2 位作者 LU Chunxia YANG He SUN Mengyu 《Chinese Geographical Science》 SCIE CSCD 2021年第1期149-166,共18页
The north-south transitional zone in China mainly consists of the Qinling-Daba Mountains. It is the most important West-East geo-ecological space in China, containing protected areas vital for biodiversity conservatio... The north-south transitional zone in China mainly consists of the Qinling-Daba Mountains. It is the most important West-East geo-ecological space in China, containing protected areas vital for biodiversity conservation and ecological security of China. The protection and rational development of its natural habitat is of great significance to China’s ecological security and integration of protected areas based on mountain forest ecosystems on a global scale. In this study, five important types of protected areas in the transitional zone were selected, and their spatial patterns were analysed. Spatial analysis methods, such as kernel density estimation and accessibility analysis, were employed for both point and areal data, and focused on four aspects: land use scale, shift in the centre of gravity, spatial agglomeration, and accessibility. In addition, policy background and evolution of spatial and temporal characteristics of the protected area system in the transitional zone from 1963 to 2017 were also examined. We analysed the characteristics and geographical significance of the West-east corridor using the spatial pattern of the protected area system from the perspective of ecological and economic spaces. We focused on spatial shape, type intersection, and key areas to analyse the spatial overlap of the protected areas. Protected area establishment was divided into three stages: initial(1956–1980), rapid development(1981–2013), and national park transformation(2014–present). These stages reflected the change in the concept of ‘simple protection—sustainable use—integration and upgrade’ for protected areas of China. The spatial centre of gravity of the protection zone system was located in the west Qinling-Daba Mountains, and its high-density core exhibited a relatively stable N-shaped structure composed of four gathering areas. Affected by factors such as geographic environment and socio-economic development density, the average access time for protected areas was high(1.56 h);wetland parks and scenic areas are located closer to the city centre. As the West-east corridor in the transitional zone extends from west to east, there is a clear spatial dislocation between the development of protected areas and the intensity of human activities. During development, differentiated goal orientation should be adopted based on the idea of zoning and classified governance. With the advancement of the construction of protected areas, the spatial overlap of protected areas in the transition zone has become more prominent. At present, the spatially overlapped protected areas in the transitional zone remain prominent, with inclusion overlap being the most common, and forest parks exhibiting the highest probability of overlap with other protected areas, we should focus on in the integration process of the corridor-type ecological space based on the mountain forest ecosystem. 展开更多
关键词 North-south transitional Zone(NSTZ) protected area(PA) spatial-temporal pattern ACCESSIBILITY the West-east corridor spatial overlap
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Quanta of the Phase-Space Areas Given by Intervals of Energy and Time Associated with Electron Transitions
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2017年第8期1158-1174,共17页
The paper examines the energy of electron transitions in an emission process and the time intervals necessary for that process. For simple quantum systems, the both parameters—that of energy and time—depend on the d... The paper examines the energy of electron transitions in an emission process and the time intervals necessary for that process. For simple quantum systems, the both parameters—that of energy and time—depend on the difference &Delta;n of the quantum numbers n labelling the beginning and end state of emission. It is shown that the phase-space areas formed by products of energy and time involved in the emission can be represented as a quadratic function of &Delta;n multiplied by the Planck constant h. 展开更多
关键词 Electron transitions Their Energies and transition Times Quanta of the Phase-Space areas of Energy and Time
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Chemical kinetics evaluation and its application of natural gas generation derived from the Yacheng Formation in the deep-water area of the Qiongdongnan Basin,China 被引量:2
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作者 SU Long ZHANG Dongwei +4 位作者 YANG Haizhang CHEN Ying CHEN Guojun ZHENG Jianjing XU Yongchang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第1期50-59,共10页
The natural gas generation process is simulated by heating source rocks of the Yacheng Formation, including the onshore-offshore mudstone and coal with kerogens of Type II2-III in the Qiongdongnan Basin. The aim is to... The natural gas generation process is simulated by heating source rocks of the Yacheng Formation, including the onshore-offshore mudstone and coal with kerogens of Type II2-III in the Qiongdongnan Basin. The aim is to quantify the natural gas generation from the Yacheng Formation and to evaluate the geological prediction and kinetic parameters using an optimization procedure based on the basin modeling of the shallow-water area. For this, the hydrocarbons produced have been grouped into four classes(C1, C2, C3 and C4-6). The results show that the onset temperature of methane generation is predicted to occur at 110℃ during the thermal history of sediments since 5.3 Ma by using data extrapolation. The hydrocarbon potential for ethane, propane and heavy gaseous hydrocarbons(C4-6) is found to be almost exhausted at geological temperature of 200℃ when the transformation ratio(TR) is over 0.8, but for which methane is determined to be about 0.5 in the shallow-water area. In contrast, the end temperature of the methane generation in the deep-water area was over 300℃ with a TR over 0.8. It plays an important role in the natural gas exploration of the deep-water basin and other basins in the broad ocean areas of China. Therefore, the natural gas exploration for the deep-water area in the Qiongdongnan Basin shall first aim at the structural traps in the Ledong, Lingshui and Beijiao sags, and in the forward direction of the structure around the sags, and then gradually develop toward the non-structural trap in the deep-water area basin of the broad ocean areas of China. 展开更多
关键词 deep—water area geological prediction natural gas Yacheng Formation EVALUATION Qiongdongnan Basin
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Dynamic change and diagnosis of physical, chemical and biological properties in bauxite residue disposal areas 被引量:4
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作者 GUO Ying ZHU Feng +2 位作者 WU Chuan TIAN Tao XUE Sheng-guo 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第2期410-421,共12页
Vegetation encroachment occurred in bauxite residue disposal area(BRDA)following natural weathering processes,whilst the typical indicators of soil formation are still uncertain.Residue samples were collected from the... Vegetation encroachment occurred in bauxite residue disposal area(BRDA)following natural weathering processes,whilst the typical indicators of soil formation are still uncertain.Residue samples were collected from the BRDA in Central China,and related physical,chemical and biological indicators of bauxite residue with different storage years were determined.The indicators of soil formation in bauxite residue were selected using principal component analysis,factor analysis,and comprehensive evaluation to establish soil quality diagnostic index model on disposal areas.Following natural weathering processes,the texture of bauxite residue changed from silty loam to sandy loam.The pH and EC decreased,whilst porosity,nutrient element content and microbial biomass increased.The identified minimum data set(MDS)included available phosphorus(AP),moisture content(MC),C/N,sand content,total nitrogen(TN),microbial biomass carbon(MBC),and pH.The soil quality index of bauxite residue increased,and the relative soil quality index decreased from 1.89 to 0.15,which indicated that natural weathering had a significant effect on improveing the quality of bauxite residue and forming a new soil-like matrix.The diagnostic model of bauxite residue was established to provide data support for the regeneration on disposal area. 展开更多
关键词 bauxite residue disposal area soil properties minimum data set diagnostic indices natural weathering soil formation in bauxite residue
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Application of the monitoring and early warning system for internal solitary waves:Take the second natural gas hydrates production test in the South China Sea as an example
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作者 Dan-yi Su Bin-bin Guo +5 位作者 Qian-yong Liang Chu-jin Liang Fei-long Lin Su-meng Jiang Yi-fei Dong Xue-min Wu 《China Geology》 CAS CSCD 2023年第4期676-684,共9页
Internal solitary waves(ISWs) contain great energy and have the characteristics of emergency and concealment. To avoid their damage to offshore engineering, a new generation of monitoring and early warning system for ... Internal solitary waves(ISWs) contain great energy and have the characteristics of emergency and concealment. To avoid their damage to offshore engineering, a new generation of monitoring and early warning system for ISWs was developed using technologies of double buoys monitoring, intelligent realtime data transmission, and automatic software identification. The system was applied to the second natural gas hydrates(NGHs) production test in the Shenhu Area, South China Sea(SCS) and successfully provided the early warning of ISWs for 173 days(from October 2019 to April 2020). The abrupt changes in the thrust force of the drilling platform under the attack of ISWs were consistent with the early warning information, proving the reliability of this system. A total of 93 ISWs were detected around the drilling platform. Most of them occurred during the spring tides in October–December 2019 and April 2020, while few of them occurred in winter. As suggested by the theoretical model, the full-depth structure of ISWs was a typical current profile of mode-1, and the velocities of wave-induced currents can reach 80 cm/s and30 cm/s, respectively, in the upper ocean and near the seabed. The ISWs may be primarily generated from the interactions between the topography and semidiurnal tides in the Luzon Strait, and then propagate westward to the drilling platform. This study could serve as an important reference for the early warning of ISWs for offshore engineering construction in the future. 展开更多
关键词 Internal solitary wave Early warning offshore engineering Drilling platform natural gas hydrates production test Shenhu area South China Sea
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Assessment of natural gas hydrate reservoirs at Site GMGS3-W19 in the Shenhu area,South China Sea based on various well logs 被引量:1
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作者 Dong-ju Kang Ying-feng Xie +4 位作者 Jing-an Lu Tong Wang Jin-qiang Liang Hong-fei Lai Yun-xin Fang 《China Geology》 CAS 2022年第3期383-392,共10页
To obtain the characteristics of the gas hydrate reservoirs at GMGS3-W19,extensive geophysical logging data and cores were analyzed to assess the reservoir properties.Sediment porosities were estimated from density,ne... To obtain the characteristics of the gas hydrate reservoirs at GMGS3-W19,extensive geophysical logging data and cores were analyzed to assess the reservoir properties.Sediment porosities were estimated from density,neutron,and nuclear magnetic resonance(NMR)logs.Both the resistivity and NMR logs were used to calculate gas hydrate saturations,the Simandoux model was employed to eliminate the effects of high clay content determined based on the ECS and core data.The density porosity was closely in agreement with the core-derived porosity,and the neutron porosity was higher while the NMR porosity was lower than the density porosity of sediments without hydrates.The resistivity log has higher vertical resolution than the NMR log and thus is more favorable for assessing gas hydrate saturation with strong heterogeneity.For the gas hydrate reservoirs at GMGS3-W19,the porosity,gas hydrate saturation and free gas saturation was 52.7%,42.7%and 10%,on average,respectively.The various logs provide different methods for the comprehensive evaluation of hydrate reservoir,which supports the selection of candidate site for gas hydrate production testing. 展开更多
关键词 natural gas hydrates(NGHs) Low gamma Reservoir properties SATURATION NMR Marine hydrates trial exploration engineering Shenhu area South China Sea
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The origin and distribution of natural gas in the frontal uplift area of the Kuqa depression,Tarim Basin 被引量:5
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作者 CUI Jie ZHU Guangyou +3 位作者 ZHANG Bin SU Jin LU Yuhong MA Chenglong 《Chinese Journal Of Geochemistry》 EI CAS 2010年第3期313-318,共6页
The frontal uplift of the Kuqa depression is an important oil and gas producing area. In this study, the distribution and origin of natural gas were discussed based on natural gas components and isotope data. The main... The frontal uplift of the Kuqa depression is an important oil and gas producing area. In this study, the distribution and origin of natural gas were discussed based on natural gas components and isotope data. The main components of natural gas were hydrocarbons with relatively high contents of C2+ component. Most gases were derived from terrestrial source rocks, and some came from marine rocks. The contents of non-hydrocarbon gases were high in the central part of the frontal uplift area and low in the two terminals. The distribution of oil composition was similar to that of natural gas, which was mainly controlled by the types of source rocks. Dry coefficient and maturity of natural gas in the frontal uplift were lower than those of gas in the Kelasu tectonic belt of the Kuqa depression, which was mainly affected by the difference of tectonic movements in both areas. In the frontal uplift, the traps were formed in the early stage and could capture the early formed oil and gas, and structural adjustment was slight in later stages, so the oil and gas could be effectively preserved. Multiperiodic oil and gas filling led to the complex distribution of natural gas. 展开更多
关键词 天然气分布 库车坳陷 隆起区 塔里木盆地 起源 非烃气体 天然气组分 碳氢化合物
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The Extent and Effectiveness of Protected Areas in the Russian Federation 被引量:1
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作者 Kseniia SERGEEVA Hui LIN 《Journal of Geodesy and Geoinformation Science》 2022年第2期75-84,共10页
To tackle environmental challenges and in particular,the problems associated with the high demand for forests and resources,the consequence of which is the degradation of ecological systems,Russia has developed the bi... To tackle environmental challenges and in particular,the problems associated with the high demand for forests and resources,the consequence of which is the degradation of ecological systems,Russia has developed the biggest network of specially protected natural areas in the world.Although the scale of SPNA may look impressive,a recent comprehensive study of the period from 2001 to 2018 brought the spotlight on protected areas in Russia experiencing significant tree loss annually.Since Russia is confronting unprecedented fires that break records every year,the problem of preserving rare animal and plant species,their habitats,and natural ecosystems is acute.This paper is intended to assess the extent and effectiveness of SPNAs with regard to wilderness conservation in the Russian Federation based on the latest data;the main focus being on the period of 2014—2019,before and after the launch of the environmental safety strategies,along with additional analysis of available data for the following year of 2020.With due consideration of unique geographical,economic,and socio-cultural circumstances,as well as historical background and legislative reality of SPNAs in Russia,we have conducted a statistical analysis of data from the official annual reports from the Federal State Statistics Service on SPNAs by territories and significance,expenditures on maintenance and ecotourism,followed by RGB analysis of satellite imagery via means of GIS software for visualization of obtained data and further analytics.Despite the growth of the SPNA network in Russia,resulting in an astonishing 2402 Mha in 2020,an estimated 4 Mha of tree loss accounted for SPNAs over the period of 2014—2019,and 134 Mha in 2020 alone.Our findings indicate a need for the application of a comprehensive GIS approach for further development and effective management of the SPNA network in Russia.Furthermore,the results include recommendations on legislative changes,engagement of locals in SPNA protection,and popularization of ecotourism,all of which can be valuable for policymakers and SPNA development. 展开更多
关键词 GIS remote sensing protected area SPNA nature conservation DEFORESTATION tree loss
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Different in-vitro and Clinical Studies to Evaluate the Improvement of the Eyes Cream Containing the Natural Algal Complex
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作者 Yang Fan Zhou Ziyan +1 位作者 Zhou Zheng Guo Miao 《China Detergent & Cosmetics》 2023年第1期79-86,共8页
A natural algal complex is prepared from the brown alga Undaria pinnatifida rich in fucoidan and the red calcareous algal Corallina officinalis. The effect of the algal complex was demonstrated by transcriptomic analy... A natural algal complex is prepared from the brown alga Undaria pinnatifida rich in fucoidan and the red calcareous algal Corallina officinalis. The effect of the algal complex was demonstrated by transcriptomic analysis on normal human fibroblasts through the DNA chip technology from AFFYMETRIX, combined with the following in vitro Elisa test and clinical studies. Clinical studies have been performed with a basic cream containing complex versus placebo on 2 groups of 30 Caucasian women for a period of 28 days. In the present study, the natural algal complex works on the crow’s feet, eye bags, and dark cycle through multiple ways of action, including enhancing natural immune responses, regulating the inflammatory and immunity process, and promoting the extracellular matrix synthesis. As the natural algal complex has excellent improvement on the eye circumference, we have applied it to mageline firming anti-wrinkle eye cream for further research. 展开更多
关键词 natural algal complex DNA chip technology dedicated area care
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THE POSSIBILITIES AND REALITIES ON THE REMANAGEMENT OF DESERTIFIED LANDS IN THE TRANSITIONAL ZONE BETWEEN THE DRY-FARMING AREA AND THE GRAZING AREA IN NORTH CHINA
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作者 朱震达 刘恕 杨有林 《Chinese Geographical Science》 SCIE CSCD 1991年第1期32-43,共12页
The desertification process is rapidly developing at present and 61.5% of the land area in the zone are already desertified.Among the desertified lands, 26.9% are seriously desertified, 25% most seriously desertified ... The desertification process is rapidly developing at present and 61.5% of the land area in the zone are already desertified.Among the desertified lands, 26.9% are seriously desertified, 25% most seriously desertified and 47.4% are the lands where desertification is under way. They are caused by over-reclamation for farming, over-grazing, unreasonable collection of firewood,the destruction of vegetation and the misuse of water resources. Under the ecological environment in semi-arid zone,the degraded environment process possesses the ability of restoring to its original status as soon as the interruption of excessive human activities are eliminated. The fencing- and-self-cultivating method is an effective measure adopted universally in semi-arid zone to cure the desertified lands.The desertified lands can be readjusted and controlled easily if other controlling measures are supplemented. The fundamental ways to control desertification are to utilize rationally the resources, to readjust the existing 展开更多
关键词 desertified lands the transitional zone BETWEEN the dry-larming area and the GRAZING area remanagement NORTH China.
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