期刊文献+
共找到3,872篇文章
< 1 2 194 >
每页显示 20 50 100
Tectonic Stress Analysis of Future Large Earthquake Zones along the Bayan Har Block Boundary,Tibet Plateau
1
作者 ZHOU Chunjing ZHAO Wenjin +1 位作者 WANG Lianjie WU Zhonghai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第2期683-684,共2页
The Bayan Har block is mainly bounded by the east Kunlun fault zone to the north, Garze-Yushu -Xianshuihe fault zone to the south and Longmenshan fault zone to the east (Fig. 1). In the past 20 years, large earthqua... The Bayan Har block is mainly bounded by the east Kunlun fault zone to the north, Garze-Yushu -Xianshuihe fault zone to the south and Longmenshan fault zone to the east (Fig. 1). In the past 20 years, large earthquakes have occurred frequently along this block's boundaries, which has received much attention among geoscientists. Whether large earthquakes will happen (and where) along this block's boundary faults in the future are two key problems that need to be addressed. This study calculates the accumulated tectonic stress and superposition of the coulomb stress caused by fault slip of 16 large earthquakes since 1904, and evaluates the possible locations of future earthquakes that may occur around this block. 展开更多
关键词 Tectonic Stress Analysis of Future Large Earthquake zones along the Bayan Har Block Boundary Tibet Plateau
下载PDF
Comparisons of the suture zones along a geotraverse from the Scythian Platform to the Arabian Platform 被引量:1
2
作者 Ali Yilmaz Shota Adamia Hüseyin Yilmaz 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第6期855-875,共21页
The area from the Greater Caucasus to the southeast Turkey is characteri:;.ed and shaped by several major continental blocks. These are Scythian Platform, Pontian-Transcaucasu.,; Continent-Arc System (PTCAS), the A... The area from the Greater Caucasus to the southeast Turkey is characteri:;.ed and shaped by several major continental blocks. These are Scythian Platform, Pontian-Transcaucasu.,; Continent-Arc System (PTCAS), the Anatolian-lranian and the Arabian Platforms. The aim of this paper is to define these continental blocks and describe and also compare their boundary relationships along the suture zones. The Scythian Platform displays the evidence of the Hercynian and Alpine orogens. This platform is separated from the PTCAS by the Greater Caucasus Suture Zone. The incipient collision began along this suture zone before middle-late Carboniferous whereas the final collision occurred before Oligocene. The PTCAS can be divided into four structural units: (1) the Georgian Block - northern part of the Pontian-Transcaucasian island-arc, (2) the southern and eastern Black Sea Coast-Adjara-Trialeti Unit, (3) the Artvin-Bolnisi Unit, comprising the northern part of the southern Transcaucasus, and (4) the Imbricated Bayburt-Garabagh Unit. The PTCAS could be separated from the Anatolian Iranian Platform by the North Anatolian-Lesser Caucasus Suture (NALCS) zone. The initial collision was developed in this suture zone during Senonian-early Eocene and final collision before middle Eocene or Oligocene-Miocene. The Anatolian-lranian Platform (AIP) is made up of the Tauride Platform and its metamorphic equivalents together with Iranian Platform. It could be separated from the Arabian Platform by the Southeastern Anatolian Suture (SEAS) zone. The collision ended before late Miocene along this suture zone. The southernmost continental block of the geotraverse is the Arabian Platform, which constitutes the northern part of the Arabian-African Plate. This platform includes a sequence from the Precambrian felsic volcanic and clastic rocks to the Campanian-early Maastrichtian fiyschoidal clastics. All the suture zones include MORB and SSZ-types ophiolites in different ages. However, the ages of the suture zones and the crustal thicknesses along the suture zones are different, as the age becoming younger, the thickness decreasing from north to south. The emplacements of the ophiolites have similar pattern of a flower structure, reflecting both the north- and south-dipping overthrusts along the suture zones. 展开更多
关键词 Scythian Plattorm Arabian Platform Suture zones Ceotraverse
下载PDF
Wildlife Crossing Zones along the Ring Changbai Mountain Scenic Highway, China
3
作者 Yun Wang Zhengji Piao +5 位作者 Lei Guan Haifeng Li Qilin Li Yayi Lu Lei Gao Jiding Chen 《Journal of Life Sciences》 2012年第12期1420-1427,共8页
The 84-km long Changbai Mountain scenic Ring highway encircles and bisects the nature reserve. With the expected increasing traffic flow, increased wildlife vehicle collisions and barrier effects are likely. In order ... The 84-km long Changbai Mountain scenic Ring highway encircles and bisects the nature reserve. With the expected increasing traffic flow, increased wildlife vehicle collisions and barrier effects are likely. In order to identify wildlife crossing zones and future protective measurement, the authors carried out 10 wildlife highway crossing surveys during the winter in 2008-2009. For each 5-kin section, the authors recorded highway crossings of all small/mid-sized and large mammals and one large protected bird species, the hazel grouse (Bonasa bonasia) and noted snow depth and the dominant vegetation type. The authors detected 12 mammal species and one avifauna species crossing the highway 502 times. The smallest of mammal was the Eurasian red squirrel (Sciurus vulgaris). Large mammals detected included the wild boar (Sus scrofe) (64) and brown bear (Ursus arctos) (1). The average number of wildlife crossings per 5 km was 29.5. It was found that species richness and crossing frequency was higher in sections with broad leaf forest compared to sections with white birch secondary forest significantly. The authors suggested that disturbance of broad leaf forest be minimized during construction and strict protection be established for broad leaf forests around Changbai Mountain National Nature Reserve. 展开更多
关键词 HIGHWAY WILDLIFE crossing zones road ecology Changbai Mountain Natural Reserve China.
下载PDF
Structural Geology and Chronology of Shear Zones along the Shangdan Suture in Qinling Orogenic Belt,China:Implications for Late Mesozoic Intra-Continental Deformation of East Asia
4
作者 Falak Sheir Wei Li +6 位作者 Le Zhang Basil Alabowsh Liuqing Jiang Li Liang Sainan Gao Shair Baz Umar Ashraf 《Journal of Earth Science》 SCIE CAS CSCD 2024年第2期376-393,共18页
The Shangdan suture zone(SDZ)in the Qinling orogenic belt(QOB)is a key to understanding the East Asia tectonic evolution.The SDZ gives information about convergent processes between the North China Block(NCB)and South... The Shangdan suture zone(SDZ)in the Qinling orogenic belt(QOB)is a key to understanding the East Asia tectonic evolution.The SDZ gives information about convergent processes between the North China Block(NCB)and South China Block(SCB).In the Late Mesozoic,several shear zones evolved along the SDZ boundary that helps us comprehend the collisional deformation between the NCB and SCB,which was neglected in previous studies.These shear zones play an essential role in the tectonic evolution of the East Asia continents.This study focuses on the deformation and geochronology of two shear zones distributed along the SDZ,identified in the Shaliangzi and Maanqiao areas.The shear sense indicators and kinematic vorticity numbers(0.54–0.90)suggest these shear zones have sinistral shear and sub-simple shear deformation kinematics.The quartz’s dynamic recrystallization and c-axis fabric analysis in the Maanqiao shear zone(MSZ)revealed that the MSZ experienced deformation under green-schist facies conditions at∼400–500℃.The Shaliangzi shear zone deformed under amphibolite facies at∼500–700℃.The^(40)Ar/^(39)Ar(muscovite-biotite)dating of samples provided a plateau age of 121–123 Ma.Together with previously published data,our results concluded that QOB was dominated by compressional tectonics during the Late Early Cretaceous.Moreover,we suggested that the Siberian Block moved back to the south and Lhasa-Qiantang-Indochina Block to the north,which promoted intra-continental compressional tectonics. 展开更多
关键词 Qinling orogenic belt Shangdan suture zone shear zone Late Mesozoic intra-continental deformation East Asia TECTONICS
原文传递
Kinematic History and Changes in the Tectonic Stress Regime during the Cenozoic along the Qinling and Southern Tanlu Fault Zones 被引量:13
5
作者 ZHANG Yueqiao Pierre Vergèly +3 位作者 Jacques-Louis Mercier WANG Yongmin ZHANG Yong HUANG Dezhi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第3期264-274,共11页
Since the mid-late Eocene, North China has been subjected to extensional stress, resulting in the formation and development of basins. The dynamic origin of this crustal extension has long been an issue of debate. Thi... Since the mid-late Eocene, North China has been subjected to extensional stress, resulting in the formation and development of basins. The dynamic origin of this crustal extension has long been an issue of debate. This paper presents the results of kinematic analyses of faults obtained from two seperated areas in North China. In the Weihe graben situated on the southernmost margin of the Ordos block, analyses of fault kinematics were coupled with an analysis of the basin's subsidence history. Three successive extensional tectonic phases accompaning the basin's formation and development have been distinguished. The Palaeogene extension was oriented in a WNW-ESE direction; the Neogene extension in a NE-SW direction and the Pliocene-Quaternary extension in a NW-SE direction. Such changes have also been recorded by fault kinematics along the southern Tanlu fault zone. This has been demonstrated by three successive sets of fault striations indicating normal dip slip resulting from NW-SE extension, then left-lateral slip with a normal component resulting from NE-SW extension, and right-lateral slip with a minor normal component, respectively. The kinematic history of faults and their chronological evolution indicate changes in continental dynamics acting in North China over Cenozoic time. 展开更多
关键词 FAULT kinematics TECTONIC stress regime QINLING and Tanlu FAULT zones
下载PDF
Study on the Modes of Chinese Overseas Industrial Cooperation Zones Along the Belt and Road 被引量:5
6
作者 Shen Zhengping Jian Xiaobin Zhao Jie 《China City Planning Review》 CSCD 2020年第1期40-49,共10页
China has established overseas industrial cooperation zones along the Belt and Road as a key platform for the advancement of the Belt and Road construction and international economic and trade cooperation,aiming to fa... China has established overseas industrial cooperation zones along the Belt and Road as a key platform for the advancement of the Belt and Road construction and international economic and trade cooperation,aiming to facilitate deep economic integration,promote mutual benefit,and achieve win-win results with countries along the Belt and Road.This paper firstly explains the definition and connotation of overseas industrial cooperation zones against the background of the Belt and Road Initiative,and then introduces the construction status of Chinese overseas industrial cooperation zones along the Belt and Road in terms of type and spatial distribution.The research conducts case studies on four types of overseas industrial cooperation zones,including agricultural industrial zones,processing industrial zones,service industrial zones,and comprehensive industrial zones.Based on the case study,it discusses the development context,planning mission,industrial function,leading enterprise,operation mode,and final comprehensive effect of Chinese overseas industrial cooperation zones.Finally,through comparing the differences with domestic experience on typical industrial cooperation zones,this paper suggests that the construction of overseas industrial cooperation zones along the Belt and Road should focus on strengthening bilateral communication between governments,further improving the cooperation mechanism,scientifically formulating industrial planning,driving construction of infrastructure facilities,and fostering and bringing in international talents. 展开更多
关键词 the BELT and ROAD OVERSEAS INDUSTRIAL cooperation zone construction mode
原文传递
A review of China’s overseas economic and trade cooperation zones along the Belt and Road:Progress and prospects 被引量:3
7
作者 MENG Guangwen WANG Ran WANG Shufang 《Journal of Geographical Sciences》 SCIE CSCD 2023年第7期1505-1526,共22页
As a new mode for Chinese overseas investment and a growth pole for industrialization and urbanization of the host countries,the overseas economic and trade cooperation zone(OETCZ) or overseas free economic zone(OFEZ)... As a new mode for Chinese overseas investment and a growth pole for industrialization and urbanization of the host countries,the overseas economic and trade cooperation zone(OETCZ) or overseas free economic zone(OFEZ) of China plays an important role under the Belt and Road Initiative.With the rising attention on OETCZ,studies regarding OETCZ have also increased.However,there is a lack of studies reviewing this topic’s progress,challenges and future directions.This paper employs a systematic review to examine the literature on the OETCZ along the Belt and Road,based on domestic and overseas studies.The results show that domestic studies account for a large proportion of the collected literature,compared to overseas studies.Interdisciplinary research focus includes inductive case studies from a classification perspective,deductive studies based on cultural and institutional perspectives,trade network and bilateral trade relations based on the perspectives of international trade and regional economy,spatial planning studies from urban planning perspective,and overseas comments and earlier studies on Japan’s and Singapore’s overseas parks from the geopolitical and international political perspectives.Despite diverse research contents and dramatic progress,limitations exist in current OETCZ-related studies,including a lack of exploration of the mechanism,questions and concerns from overseas scholars,sustainable development and other problems.Future studies should broaden and deepen research insights,including the “overseas free economic zones(OFEZ)” as a general designation to cover all other types of OETCZs,studies on the primary conditions of host countries,exploration of the theoretical issues behind China’s OETCZ,comparative study of OETCZs such as management structures,profit models,environmental standards and legal systems as well as popular issues questioned internationally. 展开更多
关键词 The Belt and Road Initiative(BRI) overseas free economic zone(OFEZ) overseas economic and trade cooperation zone(OETCZ) overseas park systematic review perspective
原文传递
Different environmental factors drive tree species diversity along elevation gradients in three climatic zones in Yunnan,southern China 被引量:1
8
作者 Xiaoyang Song Min Cao +7 位作者 Jieqiong Li Roger L.Kitching Akihiro Nakamura Melinda J.Laidlaw Yong Tang Zhenhua Sun Wenfu Zhang Jie Yang 《Plant Diversity》 SCIE CAS CSCD 2021年第6期433-443,共11页
Elevational patterns of tree diversity are well studied worldwide.However,few studies have examined how seedlings respond to elevational gradients and whether their responses vary across climatic zones.In this study,w... Elevational patterns of tree diversity are well studied worldwide.However,few studies have examined how seedlings respond to elevational gradients and whether their responses vary across climatic zones.In this study,we established three elevational transects in tropical,subtropical and subalpine mountain forests in Yunnan Province,southern China,to examine the responses of tree species and their seedlings to elevational gradients.Within each transect,we calculated species diversity indices and composition of both adult trees and seedlings at different elevations.For both adult trees and seedlings,we found that species diversity decreased with increasing elevation in both tropical and subalpine transects.Species composition showed significant elevational separation within all three transects.Many species had specific elevational preferences,but abundant tree species that occurred at specific elevations tended to have very limited recruitment in the understory.Our results highlight that the major factors that determine elevational distributions of tree species vary across climatic zones.Specifically,we found that the contribution of air temperature to tree species composition increased from tropical to subalpine transects,whereas the contribution of soil moisture decreased across these transects. 展开更多
关键词 Air temperature Climate zones Montane forest Soil moisture SEEDLING Tree species distribution
下载PDF
Study on Integrated Recurrence Behaviors of Strong Earthquakes Along Entire Active Fault Zones in the Sichuan-Yunnan Region, China 被引量:1
9
作者 YiGuixi WenXueze XuXiwei 《Earthquake Research in China》 2003年第2期145-159,共15页
Based on historical earthquake data, we use statistical methods to study integrated recurrence behaviors of strong earthquakes along 7 selected active fault zones in the Sichuan-Yunnan region. The results show that re... Based on historical earthquake data, we use statistical methods to study integrated recurrence behaviors of strong earthquakes along 7 selected active fault zones in the Sichuan-Yunnan region. The results show that recurrences of strong earthquakes in the 7 fault zones display near-random, random and clustering behaviors. The recurrence processes are never quasi-periodic, and are neither strength-time nor time-strength dependent. The more independent segments for strong earthquake rupturing a fault zone has, the more complicated the corresponding recurrence process is. And relatively active periods and quiescent periods for earthquake activity occur alternatively. Within the active periods, the distribution of recurrence time intervals between earthquakes has relatively large discretion, and can be modelled well by a Weibull distribution. The time distribution of the quiescent periods has relatively small discretion, and can be approximately described by some distributions as the normal. Both the durations of the active periods and the numbers of strong earthquakes within the active periods vary obviously cycle by cycle, leading to the relatively active periods having never repeated quasi-periodically. Therefore, the probabilistic assessment for middle- and long-term seismic hazard for entireties of active fault zones based on data of historical strong earthquakes on the fault zones still faces difficulty. 展开更多
关键词 Historical earthquake Active fault zone Recurrence interval Probability distribution The Sichuan-Yunnan region
下载PDF
Dynamic Identification and Evolution of Urban-suburban-rural Transition Zones Based on the Blender of Natural and Humanistic Factors: A Case Study of Chengdu, China
10
作者 DENG Wei JIANG Zhenyuan +3 位作者 ZHANG Shaoyao REN Ping ZHANG Hao WANG Zhanyun 《Chinese Geographical Science》 SCIE CSCD 2024年第5期791-809,共19页
Urban-suburban-rural(U-S-R)zones exhibit distinctive transitional characteristics in interaction between human and nature.U-S-R transition zones(U-S-RTZ)are also highlighting the function diversity and landscape heter... Urban-suburban-rural(U-S-R)zones exhibit distinctive transitional characteristics in interaction between human and nature.U-S-R transition zones(U-S-RTZ)are also highlighting the function diversity and landscape heterogeneity across territorial spaces.As a super megacity in western China,Chengdu’s rapid urbanization has driven the evolution of U-S-R spaces,resulting in a sequential structure.To promote the high-quality spatial development of urban-rural region in a structured and efficient manner,it is essential to con-duct a scientific examination of the multidimensional interconnection within the U-S-RTZ framework.By proposing a novel identifica-tion method of U-S-RTZ and taking Chengdu,China as a case study,grounded in a blender of natural and humanistic factors,this study quantitatively delineated and explored the spatial evolutions of U-S-RTZ and stated the optimization orientation and sustainable devel-opment strategies of the production-living-ecological spaces along the U-S-R gradients.The results show that:1)it is suitable for the quantitative analysis of U-S-RTZ by established three-dimensional identification system in this study.2)In 1990-2020,the urban-sub-urban transition zones(U-STZ)in Chengdu have continuously undergone a substantial increase,and the scale of the suburban-rural transition zones(S-RTZ)has continued to expand slightly,while the space of rural-ecological transition zones(R-ETZ)has noticeably compressed.3)The landuse dynamics within U-S-RTZ has gradually increased in 1990-2020.The main direction of landuse transition was from farmland to construction land or woodlands,with the expansion of construction land being the most significant.4)R-ETZ primarily focus on ecological functions,and there is a trade-off relationship between the production-ecological function within the S-RTZ,and in the U-STZ,production-living composite functions are prioritized.This study emphasizes the importance of elastic planning and precise governance within the U-S-RTZ in a rapid urbanization region,particularly highlighting the role of suburbs as landscape corridors and service hubs in urban-rural integration.It elucidates to the practical implications for achieving high-quality development of integrated U-S-R territorial spaces. 展开更多
关键词 transition zone urban-suburban-rural zones spatial identification evolution mechanism Chengdu China
下载PDF
Formation mechanism of fault accommodation zones under combined stress in graben basin:Implications from geomechanical modeling
11
作者 Qi-Qiang Ren Jin-Liang Gao +3 位作者 Rong-Tao Jiang Jin Wang Meng-Ping Li Jian-Wei Feng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期54-76,共23页
A fault accommodation zone is a type of structure that is defined as regulating displacement and strain between faults structure.Increasing numbers of fault accommodation zones are being identified in graben basins,in... A fault accommodation zone is a type of structure that is defined as regulating displacement and strain between faults structure.Increasing numbers of fault accommodation zones are being identified in graben basins,indicating the potential exploration target and petroleum accumulation areas.This study aims to analyze the formation mechanism and development of fault accommodation zones under combined stress by a numerical simulation method considering geomechanical modeling.Using three-dimensional(3-D)seismic interpretation and fractal dimension method,exampled with the Dongxin fault zone,the fault activity and fault combination pattern were conducted to quantitatively characterize the activity difference in fault accommodation zones.Combined with mechanical experiment test,a geomehcanical model was established for fault accommodation zones in a graben basin.Integrating the paleostress numerical simulations and structural physical simulation experiment,the developmental characteristics and genetic mechanism of fault accommodation zones were summarized.Influenced by multi movements and combined stresses,three significant tectonic evolution stages of the Dongxing Fault Zone(DXFZ)were distinguished:During the E_(s)^(3)sedimentary period,the large difference in the stress,strain,and rupture distribution in various faults were significant,and this stage was the key generation period for the prototype of the DXFZ,including the FAZ between large-scale faults.During the E_(s)^(2)sedimentary period,the EW-trending symmetric with opposite dipping normal faults and the NE-SW trending faults with large scale were furtherly developed.The junction area of two secondary normal faults were prone to be ruptured,performing significant period for inheriting and developing characteristics of fault accommodation zones.During the Es1 sedimentary period,the high-order faults in the DXFZ exhibited the obvious fault depressions and strike-slip activity,and the fault accommodation zones were furtherly inherited and developed.This stage was the molded and formative period of the FAZ,the low-order faults,and the depression in the DXFZ. 展开更多
关键词 Fault accommodation zone Graben basin Fault activity Tectonic physical simulation experiment Finite element numerical simulation Dongxin fault zone
下载PDF
Capacity planning of hydro-wind-solar hybrid power systems considering hydropower forbidden zones
12
作者 Zhiyu Yan Lu Zhang Fulong Song 《Global Energy Interconnection》 EI CSCD 2024年第6期798-811,共14页
In the capacity planning of hydro-wind-solar power systems(CPHPS),it is crucial to use flexible hydropower to complement the variable wind-solar power.Hydropower units must be operated such that they avoid specific re... In the capacity planning of hydro-wind-solar power systems(CPHPS),it is crucial to use flexible hydropower to complement the variable wind-solar power.Hydropower units must be operated such that they avoid specific restricted operation zones,that is,forbidden zones(FZs),to avoid the risks associated with hydropower unit vibration.FZs cause limitations in terms of both the hydropower generation and flexible regulation in the hydro-wind-solar power systems.Therefore,it is essential to consider FZs when determining the optimal wind-solar power capacity that can be compensated by the hydropower.This study presents a mathematical model that incorporates the FZ constraints into the CPHPS problem.Firstly,the FZs of the hydropower units are converted into those of the hydropower plants based on set theory.Secondly,a mathematical model was formulated for the CPHPS,which couples the FZ constraints of hydropower plants with other operational constraints(e.g.,power balance constraints,new energy consumption limits,and hydropower generation functions).Thirdly,dynamic programming with successive approximations is employed to solve the proposed model.Lastly,case studies were conducted on the hydro-wind-solar system of the Qingshui River to demonstrate the effectiveness of the proposed model. 展开更多
关键词 Forbidden zones Hydro-wind-solar power systems Capacity planning Hydropower flexibility Set theory Dynamic programming with successive approximation
下载PDF
Numerical investigation of geostress influence on the grouting reinforcement effectiveness of tunnel surrounding rock mass in fault fracture zones
13
作者 Xiangyu Xu Zhijun Wu +3 位作者 Lei Weng Zhaofei Chu Quansheng Liu Yuan Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期81-101,共21页
Grouting is a widely used approach to reinforce broken surrounding rock mass during the construction of underground tunnels in fault fracture zones,and its reinforcement effectiveness is highly affected by geostress.I... Grouting is a widely used approach to reinforce broken surrounding rock mass during the construction of underground tunnels in fault fracture zones,and its reinforcement effectiveness is highly affected by geostress.In this study,a numerical manifold method(NMM)based simulator has been developed to examine the impact of geostress conditions on grouting reinforcement during tunnel excavation.To develop this simulator,a detection technique for identifying slurry migration channels and an improved fluid-solid coupling(FeS)framework,which considers the influence of fracture properties and geostress states,is developed and incorporated into a zero-thickness cohesive element(ZE)based NMM(Co-NMM)for simulating tunnel excavation.Additionally,to simulate coagulation of injected slurry,a bonding repair algorithm is further proposed based on the ZE model.To verify the accuracy of the proposed simulator,a series of simulations about slurry migration in single fractures and fracture networks are numerically reproduced,and the results align well with analytical and laboratory test results.Furthermore,these numerical results show that neglecting the influence of geostress condition can lead to a serious over-estimation of slurry migration range and reinforcement effectiveness.After validations,a series of simulations about tunnel grouting reinforcement and tunnel excavation in fault fracture zones with varying fracture densities under different geostress conditions are conducted.Based on these simula-tions,the influence of geostress conditions and the optimization of grouting schemes are discussed. 展开更多
关键词 Numerical manifold method(NMM) Grouting reinforcement Geostress condition Fault fracture zone Tunnel excavation
下载PDF
Evaluation of excavation damaged zones(EDZs)in Horonobe Underground Research Laboratory(URL)
14
作者 Koji Hata Sumio Niunoya +1 位作者 Kazuhei Aoyagi Nobukatsu Miyara 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期365-378,共14页
Excavation of underground caverns,such as mountain tunnels and energy-storage caverns,may cause the damages to the surrounding rock as a result of the stress redistribution.In this influenced zone,new cracks and disco... Excavation of underground caverns,such as mountain tunnels and energy-storage caverns,may cause the damages to the surrounding rock as a result of the stress redistribution.In this influenced zone,new cracks and discontinuities are created or propagate in the rock mass.Therefore,it is effective to measure and evaluate the acoustic emission(AE)events generated by the rocks,which is a small elastic vibration,and permeability change.The authors have developed a long-term measurement device that incorporates an optical AE(O-AE)sensor,an optical pore pressure sensor,and an optical temperature sensor in a single multi-optical measurement probe(MOP).Japan Atomic Energy Agency has been conducting R&D activities to enhance the reliability of high-level radioactive waste(HLW)deep geological disposal technology.In a high-level radioactive disposal project,one of the challenges is the development of methods for long-term monitoring of rock mass behavior.Therefore,in January 2014,the long-term measurements of the hydro-mechanical behavior of the rock mass were launched using the developed MOP in the vicinity of 350 m below the surface at the Horonobe Underground Research Center.The measurement results show that AEs occur frequently up to 1.5 m from the wall during excavation.In addition,hydraulic conductivity increased by 2e4 orders of magnitude.Elastoplastic analysis revealed that the hydraulic behavior of the rock mass affected the pore pressure fluctuations and caused micro-fractures.Based on this,a conceptual model is developed to represent the excavation damaged zone(EDZ),which contributes to the safe geological disposal of radioactive waste. 展开更多
关键词 Excavation damaged zone(EDZ) Optical sensor Long-term monitoring Acoustic emission(AE) Shaft sinking
下载PDF
Characteristics of transfer zones under the influence of preexisting faults and regional stress transformation:Wenchang A subsag,Zhujiang River Mouth Basin,northern South China Sea
15
作者 Wei LI Mingyue CAO +7 位作者 Meifang MENG Caiwei FAN Hui LI Jia LI Wanqiu WU Ruiqing QIN Xingan LI Yiming LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期744-759,共16页
A transfer zone in rift basins preserves important information on regional tectonic evolution and plays significant roles in hydrocarbon accumulation.Based on the systematic analysis of 3D seismic data and hydrocarbon... A transfer zone in rift basins preserves important information on regional tectonic evolution and plays significant roles in hydrocarbon accumulation.Based on the systematic analysis of 3D seismic data and hydrocarbon accumulation conditions,the geometry,kinematics,and reservoir control of a large synthetic overlapping transfer zone in the south of the Wenchang A subsag in the Zhujiang(Pearl)River Mouth basin were investigated.Results indicate that the development and evolution of the transfer zone was controlled by the interaction between pre-existing faults and regional stress transformation.The intense rifting of the main faults of the transfer zone controlled the development of source rocks and faultcontrolled slope break paleogeomorphology.The strike-slip overprint since the Oligocene is conducive to the formation of a large-scale fault-anticline trap,and the secondary faults in the transfer zone contribute to the hydrocarbon transportation.The conjugate intersection area of the NE-and NW-trending faults offers more opportunity for hydrocarbon migration and accumulation. 展开更多
关键词 transfer zone pre-existing fault regional stress transformation CENOZOIC Wenchang A Subsag Zhujiang(Pearl)River Mouth Basin
下载PDF
The Tenth Anniversary of Free Trade Pilot Zones in China:Fundamental Experiences and Enhancement Strategies
16
作者 Pei Changhong 《China Economist》 2024年第3期2-20,共19页
Since the 18th National Congress of the Communist Party of China,the country has established 21 Free Trade Pilot Zones(FTZs),achieving significant pioneering results in reform and opening up and creating a strong demo... Since the 18th National Congress of the Communist Party of China,the country has established 21 Free Trade Pilot Zones(FTZs),achieving significant pioneering results in reform and opening up and creating a strong demonstrative effect nationwide.The basic experience from a decade of FTZs includes:adhering to the centralized and unified leadership of the CPC Central Committee;combining top-level design with encouragement of grassroots innovation;leveraging the distinct characteristics and strengths of FTZs to form a differentiated development pattern;maintaining the integration of opening up with domestic reforms;using openness to drive reforms;and organically combining openness with national security assurance.Under the current and future new circumstances,China’s FTZs face new challenges and tasks.In accordance with the directives of the 20th National Congress of the Communist Party of China,an enhancement strategy for the FTZs needs to be implemented.This involves the following:First,accurately understanding and responding to the changing situation to create strategic opportunities.Second,shifting paradigms to implement innovation-driven strategies,using the new development pattern concept to guide the reform experiments and construction of the FTZs.Third,granting more autonomy to FTZs for reforms,pursuing progress while maintaining stability,and solidly advancing the reform experiments in the FTZs.Fourth,orderly expanding the opening up of the service sector and cautiously advancing the internationalization of the renminbi.Fifth,promoting innovative development in trade to build a strong trade nation.Sixth,establishing synergy with bilateral FTZs,Belt and Road cooperation,and national diplomatic strategies to enhance the linkage effect. 展开更多
关键词 Tenth anniversary of Free Trade Pilot zones experience summary enhancement strategy conception
下载PDF
Twenty-Three Years of Insect Pollinator-Dependent Crop Studies in Agro-Ecological Zones of Cameroon (2011-2020)
17
作者 Népidé Ndobadé Carine Egono Ndemé Carole Christèle +1 位作者 Daniel Farda Mazi Sanda 《Agricultural Sciences》 2024年第8期877-908,共32页
Cultivation of pollinator-dependent crops has expanded globally, increasing our reliance on insect pollination. This essential ecosystem service is provided by a wide range of managed and wild pollinators whose abunda... Cultivation of pollinator-dependent crops has expanded globally, increasing our reliance on insect pollination. This essential ecosystem service is provided by a wide range of managed and wild pollinators whose abundance and diversity are thought to be in decline, threatening sustainable food production. In Cameroon, several studies on pollinator-dependent crops carried out in different agro-ecological zones (AEZ) have been published in national and international journals, in order to present the importance and impact of flowering insects on fruit and seed yields of plant species. We proposed to produce a review article highlighting the different flowering insects and their importance for different plants according to AEZ, without however focusing on the quality of the journal (predator or non-predator) and how the different insects were identified (scientific names given in the publications). Thus, from 1997 to 2020, we collected 116 published papers from which only 26 were kept for this review. The results show that Hymenoptera, including the Apidae, followed by Megachilidae, are the most excellent pollinators of plant species in Cameroon, and they are present in different agro-ecological zones. The majority of publications focused on bees, particularly the honeybee Apis mellifera. 展开更多
关键词 Agro-Ecological zones Cameroon Flowering Insects HYMENOPTERA POLLINATORS
下载PDF
A New Model The Chinese-invested Sihanoukville Special Economic Zone has become the benchmark for cooperative economic zones in Global South countries
18
作者 Zhao Shulan Li Yilin 《China Report ASEAN》 2024年第11期42-43,共2页
The Sihanoukville Special Economic Zone(SSEZ)is the only national-level special economic zone under an agreement between the Chinese and Cambodian governments.It was established in 2008,and the then Cambodian Prime Mi... The Sihanoukville Special Economic Zone(SSEZ)is the only national-level special economic zone under an agreement between the Chinese and Cambodian governments.It was established in 2008,and the then Cambodian Prime Minister Hun Sen attended the ground-breaking ceremony.From January to September 2024,the volume of trade in goods by enterprises in the zone reached US$3.06 billion,up 22.06 percent year on year,accounting for 7.13 percent of Cambodia’s total volume of imports and exports.The SSEZ’s contribution to the local economy has risen to a new record high.Its success has created a new model for cooperative economic zones in the Global South. 展开更多
关键词 invested Zone BREAKING
下载PDF
Disparities in Prevalence and Determinants of Hypertension amongst Bamiléké Adults Residing in Two Different Agroecological Zones of Cameroon
19
作者 Maxwell Wandji Nguedjo Nanhah Kamga Jules Vidal +7 位作者 Alice Louise Woguia Pauline Vervaine Hagbe David Goda Dany Joël Ngassa Ngoumen Hippolyte Tene Mouafo Boris Gabin Kingue Azantsa Judith Laure Ngondi Julius Enyong Oben 《Open Journal of Epidemiology》 2024年第3期419-443,共25页
Background: Cardiovascular diseases such as hypertension (HTN) are one of the main causes of death in Cameroon. This study aimed at assessing prevalence disparities and determinants of hypertension amongst Bamilé... Background: Cardiovascular diseases such as hypertension (HTN) are one of the main causes of death in Cameroon. This study aimed at assessing prevalence disparities and determinants of hypertension amongst Bamiléké adults residing in two different agroecological zones of Cameroon. Methods: A cross-sectional and descriptive survey was conducted among Bamiléké population living in the Highlands zone (Western region) and in the Monomodal Rainforest zone (Littoral region) of Cameroon from August 2016 to August 2017. Participants (962) were aged at least 20 years old. Data on sociodemographic, hemodynamic, anthropometric, and biochemical parameters and lifestyle of the participants were collected. Results: Results obtained revealed that 34.2% were hypertensive and those residing in the highland zone were more affected than those living in the monomodal rainforest zone (44.5% vs 22.9%). The different subtypes of HTN (Isolated systolic hypertension (14.1%), isolated diastolic hypertension (7.2%) and Systo-diastolic hypertension (23.3%)) were also more prevalent in the Highlands Zone. The most prevalent stage of HTN was pre-HTN (31.5%). However, people living in the monomodal rainforest zone were more affected by pre-HTN compared to Bamiléké living in the highland zone (33.6% vs. 29.6%). Results also showed that high consumption (≥ 3 times/week) of carbohydrate- and fat-rich foods, ageing, obesity, and marital status were associated with high blood pressure in both agroecological zones. Besides, secondary education (OR = 0.68;95% CI: 0.42 - 0.99) in the Highlands Zone and high (≥3 times/week) vegetable consumption (OR = 0.66;95% CI: 0.44 - 0.98) in the Monomodal Rainforest Zone had a protective effect on elevated blood pressure of population. Conclusion: There is a disparity in the prevalence of hypertension and some of its determinants among Bamiléké adults residing in different agroecological zones. This work highlights the need to advocate for local and ethno-cultural health policies to prevent, diagnose and manage hypertension. 展开更多
关键词 HYPERTENSION DISPARITIES Determinants Bamiléké Ethnic Group Agroecological Zone
下载PDF
Trade-Offs and Synergie Effects of Regulating Ecosystem Services along an Climatic Gradient in Slovakia
20
作者 Jarmila Makovníková Stanislav Kološta Boris Pálka 《Journal of Geoscience and Environment Protection》 2024年第6期135-150,共16页
This study aims to assess the synergies and trade-offs of regulating ecosystem services. Ecosystem services are non-linearly interconnected and changes in one service can positively or negatively affect another. We ev... This study aims to assess the synergies and trade-offs of regulating ecosystem services. Ecosystem services are non-linearly interconnected and changes in one service can positively or negatively affect another. We evaluated ecosystem services based on biophysical indicators using an expert scoring system that determines the corresponding soil functions and is part of the existing databases available in Slovakia. This methodological combination enabled us to provide unique mapping and assessment of ecosystem services within Slovakia. Correlation analysis between individual regulating ecosystem services and climate regions, slope, texture, and altitude confirm the statistically significant influence of climate and slope in all agricultural land, arable land, and grassland ecosystems. Statistically significant synergistic effects were established between the regulation of the water regime and the regulation of soil erosion within each climate region, apart from the very warm climate region. Only in a very warm climate region was potential of regulating ecosystem services mutually beneficial for soil erosion control and soil cleaning potential (immobilization of inorganic pollutants). 展开更多
关键词 Agroecosystem Services Climatic Zone MAPPING Trade-Offs SYNERGIES
下载PDF
上一页 1 2 194 下一页 到第
使用帮助 返回顶部