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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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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
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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
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Mass-Based Environmental Factor and Energy Assessment of Microwave-Assisted Synthesized Transition Metal Nanostructures
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作者 Victor J. Law 《American Journal of Analytical Chemistry》 CAS 2024年第6期201-218,共18页
This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy... This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy budget (measured in kJ) on the horizontal axes and process density (measured in kJg−1) on the vertical axes. These two axes allow both mass usage efficiency (Environmental-Factor) and energy efficiency to be evaluated for a range of microwave applicator and metal synthesis. The metrics are allied to the: second, sixth and eleventh principle of the twelve principle of Green Chemistry. This analytical approach to microwave synthesis (widely considered as a useful Green Chemistry energy source) allows a quantified dynamic environmental quotient to be given to renewable plant-based biomass associated with the reduction of the metal precursors. Thus allowing a degree of quantification of claimed “eco-friendly” and “sustainable” synthesis with regard to waste production and energy usage. 展开更多
关键词 Microwave-Assisted Synthesis transition Metals Nanostructures Allometry Scaling power-Law Signature Green Chemistry
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Influence of Evaporating Under the Clouds on the Precipitation Stable Isotope in the Transition Zone Between Tibetan Plateau and Arid Region of China 被引量:1
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作者 GUI Juan LI Zongxing +3 位作者 DU Fa ZHANG Baijuan XUE Jian CUI Qiao 《Chinese Geographical Science》 SCIE CSCD 2023年第4期764-778,共15页
Consideration of stable isotopes in precipitation is valuable for investigating hydrological processes.Therefore,correcting the measured isotopic composition of precipitation under below-cloud evaporation is necessary... Consideration of stable isotopes in precipitation is valuable for investigating hydrological processes.Therefore,correcting the measured isotopic composition of precipitation under below-cloud evaporation is necessary.An accurate description of the underlying processes affecting stable isotopic composition of precipitation could help improve our understanding of the water cycle.The transitivity between monsoonal and arid climates was reflected by the evaporation rate of falling raindrops in precipitation in the Qilian Mountains,a typical transition zone between Tibetan Plateau and arid region of China.Considering 1310 precipitation event-scale samples,based on stable isotope analysis method,the mean below-cloud evaporation rate(f)in the study area was measured as 12.00%during the summer half-year(May-October).The evaporation rate on the northern slopes(12.70%)of the Qilian Mountains in China was significantly higher than that on the southern slopes(9.98%).The transition between monsoonal and arid climates was reflected in the evaporation rate of falling raindrops during precipitation in the Qilian Mountains of China.Below-cloud evaporation contributed to a noticeable enrichment of stable isotopes in the precipitation in the study area.The monthly precipitationδ^(18)O enrichment rate in the Qilian Mountains of China from May to October was 29.18%,23.35%,25.60%,22.99%,31.64%,and 14.72%,respectively.For every 1.00%increase in the evaporation rate of raindrops in Qilian Mountains of China,the changes in the concentration of oxygen isotopes from the bottom of the clouds to the ground increased by 0.92‰;however,with an evaporation rate of<5.00%,for every 1.00%increase in the evaporation rate of raindrops the changes in the concentration of oxygen isotopes from the bottom of the clouds to the ground increased by 1.00‰could also be observed.Furthermore,altitude was an important factor affecting below-cloud evaporation in the study area. 展开更多
关键词 below-cloud evaporation stable isotopes transition zone Qilian Mountains of china
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The sedimentary record of the Sanshui Basin:Implication to the Late Cretaceous tectonic evolution in the northern margin of South China Sea
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作者 Zhe ZHANG Nianqiao FANG Zhen SUN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期532-549,共18页
Whether the South China continental margin had shifted from active subduction to passive extension in the Late Cretaceous remains controversial.Located in the northernmost of the South China Sea continental margin,San... Whether the South China continental margin had shifted from active subduction to passive extension in the Late Cretaceous remains controversial.Located in the northernmost of the South China Sea continental margin,Sanshui Basin developed continuous stratigraphy from Lower Cretaceous to Eocene and provides precious outcrops to study the regional tectonic evolution during the Cretaceous.Therefore,we conducted field observations,petrology,clay mineralogy,geochemistry,and detrital zircon chronology analyses of sedimentary rocks from the Upper Cretaceous Sanshui Formation in Sanshui Basin.Results suggest that the Sanshui Basin is characterized as an intermoutane basin with multiple provenances,strong hydrodynamic environment,and proximal accumulation in the Late Cretaceous.An angular unconformity at the boundary between the Lower and Upper Cretaceous was observed in the basin.The sedimentary facies of the northern basin changed from lacustrine sedimentary environment in the Early Cretaceous to alluvial facies in the Late Cretaceous.The zircon U-Pb ages of granitic gravelly sandstone from Sanshui Formation prominently range from 100 Ma to 300 Ma,which is close to the deposition age of Sanshui Formation.The major and trace elements of the Late Cretaceous sedimentary samples show characteristics of active continental margin,and are different from the Paleogene rifting sequences.Hence,we propose that the northern South China Sea margin underwent an intense tectonic uplift at the turn of the Early and Late Cretaceous(around 100 Ma).Afterward,the northern South China Sea margin entered a wide extension stage in the Late Cretaceous(~100 to~80 Ma).This extensional phase is related to the back-arc extension in the active continental margin environment,which is different from the later passive rifting in the Cenozoic.The transition from active subduction to passive extension in the northern South China Sea may occur between the late Late Cretaceous and the Paleogene. 展开更多
关键词 continental margin South china Sea Sanshui Basin Late Cretaceous tectonic transition
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Key Technical Problems to be Solved in theCurrent Power Industy Development——Excerpted from the speech on the Seminar on Analysis Forecast of Economic Situation and Enterprise Reform
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作者 张晓鲁 《Electricity》 2002年第2期3-4,共2页
This paper briefs the development policies and focal construction points of powerindustry in China in 10th Five-year Plan period, and in accordance with the developmentaltrends of international power technology, puts ... This paper briefs the development policies and focal construction points of powerindustry in China in 10th Five-year Plan period, and in accordance with the developmentaltrends of international power technology, puts forward the key technological problems tobe studies in China power industry currently.[ 展开更多
关键词 china electric power industry development policy power construction keytechnology
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Status, Transition, and Impact of the Yoon Suk-yeol Administration’s Trade Policy with China
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作者 Yuge Liu 《Proceedings of Business and Economic Studies》 2023年第1期15-19,共5页
China is Korea’s main trade partner in East Asia and one of its key economic and trade partners worldwide.The two countries have complementary industrial structure and a long history of trade exchanges.However,agains... China is Korea’s main trade partner in East Asia and one of its key economic and trade partners worldwide.The two countries have complementary industrial structure and a long history of trade exchanges.However,against the backdrop of a return to global trade protectionism and the politicization of international affairs with Yoon Suk-yeol coming to power,South Korea has undertaken a strong trade shift toward the United States(US),triggering a change in the pattern of economic cooperation in East Asia and challenging the regional trade structure.A review of the trade policy agenda of the Yoon Suk-yeol administration toward the US and China,along with a comparative review of Korea’s foreign trade stance under Moon Jae-in,allows for an analysis of the turnaround and characteristics of Yoon’s trade policy toward China during his tenure.The implications for global trade governance and regional security are further analyzed with an aim of finding a Nash equilibrium in trade cooperation among East Asian countries. 展开更多
关键词 Yoon Suk-yeol administration Trade policy with china transition Economic cooperation Economic layout of East Asia
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Approach to the Geopolitical Influences of Great Powers in Southeast Asia: Case Studies of China and the US 被引量:3
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作者 QIN Qi CHENG Shengkui +3 位作者 LI Fei ZHANG Shuwen WU Liang ZHANG Dan 《Chinese Geographical Science》 SCIE CSCD 2019年第2期341-351,共11页
A quantitative approach to the national geopolitical influence is helpful to provide a reference for national sustainable development on the international stage, based on describing national diplomatic capacity and ov... A quantitative approach to the national geopolitical influence is helpful to provide a reference for national sustainable development on the international stage, based on describing national diplomatic capacity and overseas influence. Herein, this study proposes a complex geopolitical influence model, considering the affected nations' response. The geopolitical influences of great power in the affected nation are correlated with overall strength, the acceptance degree of the affected nation to the great power and the distance between both sides. Then, the geopolitical influences of China and the US in Southeast Asia countries are empirically analyzed from 2005 to 2015. The geopolitical influence of China in Southeast Asia has been largely growing for the past decades, accompanying with a constant trend of the US' effects. It is believed that China and the US can coexist peacefully in Southeast Asia to promote the regional development, and jointly create an open, inclusive and balanced regional cooperation architecture that benefits all nations in this region and great powers, through mutual political trust and economic beneficial cooperation. This study may contribute to advancing the policy debate and determining the optimal cooperation in pledging commitment to a new and sustainable model of great power relationship among the various regional geopolitical options. 展开更多
关键词 geopolitical influence GREAT power SOUtheAST ASIA china the us
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Geochemistry and Petrogenesis of Volcanic Rocks from the Continent-Ocean Transition Zone in Northern South China Sea and Their Tectonic Implications 被引量:1
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作者 XU Yue YANG Yaoming +6 位作者 YU Hongjun GAO Wei GAO Xiangxing LIU Baohua TIAN Xu YANG Jichao ZHANG Wenquan 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第5期1051-1061,共11页
Miocene–Pliocene(22–5 Myr) volcanism and associated seamounts are abundant in the continent-ocean transition(COT) zone in the margin of the north South China Sea(SCS). The petrogenesis of volcanic rocks from these s... Miocene–Pliocene(22–5 Myr) volcanism and associated seamounts are abundant in the continent-ocean transition(COT) zone in the margin of the north South China Sea(SCS). The petrogenesis of volcanic rocks from these seamounts and regional tectonic evolution of COT zone are poorly known. In this paper, we obtained whole-rock major and trace element compositions and Sr-Nd-Pb isotopic data for these volcanic rocks from the Puyuan and Beipo seamounts within COT zone, in northeastern SCS. Based on the geochemical analyses, the volcanic rocks are classified as alkaline ocean island basalts(OIB) and enriched mid-ocean ridge basalts(E-MORB). The OIBs from the Puyuan seamount are alkaline trachybasalts and tephrites that show enrichment of the light rare earth elements(LREE) relative to heavy rare earth elements(HREE) and more radiogenic Sr-Nd isotopic compositions, and have significant ‘Dupal isotopic anomaly'. In contrast, the E-MORBs from the Beipo seamount are tholeiitic basalts that have less enrichment in LREE and less radiogenic Sr-Nd isotopic compositions than the counterparts from the Puyuan seamount. Petrological and geochemical differences between the OIBs and MORBs from these two seamounts can be explained by different mantle sources and tectonic evolution stages of the COT zone. Syn-spreading OIB type basalts from the Puyuan seamount were derived from an isotopically ‘enriched', and garnet facies-dominated pyroxenitic mantle transferred by the Hainan mantle plume. In contrast, post-spreading E-MORB type basalts from the Beipo seamount are considered to be derived from the melting of isotopically ‘depleted' pyroxenite mantle triggered by lithosphere bending and subsequent post-rifting at the lower continental slope of the northern margin. 展开更多
关键词 volcanic rocks GEOCHEMISTRY tectonic evolution South china Sea continent-ocean transition zone
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Petrogenesis of the Early Cretaceous Laojunshan monzogranite at the southern margin of the North China Craton: Constrains on the transition of the tectonic regime 被引量:1
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作者 CAO Leitao TANG Huayun +4 位作者 ZHENG Jianping REN Hongwei YU Chunmei XU Zhou HE Shuai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期70-71,共2页
1 Introduction Voluminous Mesozoic magmatic rocks containing abundant Au-Mo polymetallic mineralization resources are developed in the Xiaoqinling-Xiong’ershan district of the southern margin of the North China Crato... 1 Introduction Voluminous Mesozoic magmatic rocks containing abundant Au-Mo polymetallic mineralization resources are developed in the Xiaoqinling-Xiong’ershan district of the southern margin of the North China Craton(NCC). 展开更多
关键词 Petrogenesis of the Early Cretaceous Laojunshan monzogranite at the southern margin of the North china Craton high Constrains on the transition of the tectonic regime Pb NCC TDM
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Myanmar's Political Transition and the Adjustments of U Thein Sein Administra-tion's Policies towards China
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作者 LI Chenyang ZHANG Tian 《东南亚研究》 CSSCI 2018年第2期152-158,共7页
During 2010-2011, Myanmar started its political transition. The U Thein SeinAdministration has made obvious policy adjustments towards China after it replaced the Mili-tary government. However, such adjustments were l... During 2010-2011, Myanmar started its political transition. The U Thein SeinAdministration has made obvious policy adjustments towards China after it replaced the Mili-tary government. However, such adjustments were limited, as Myanmar hasn't totally lean tothe West, but keeping relatively closer political contact with China. Empirical analysis showsthat political institu6on and ideology are not the key reasons leading to such adjustments?China-Myanmar relations had undergone fluctuation, osdlla6on and stability during 2011-2016, the root causes of which are the legality of political power, national security based ongeopolitics and economic development demands of" Myanmar people. Moreover, those threefactors remain the primary considerations of the NLD Government when it handling relationswith China. 展开更多
关键词 POLITICAL transition Myanmar the U thein SEIN Administration POLICIES to-wards china LEGALITY of POLITICAL power Geopolitics
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Medium-term and Long-term Environmental Economic Policies on Thermal Power Industry in China Seen from the New Environment Protection Law
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作者 Wang Sheng Guo Tongshu +1 位作者 Sun Xueli Li Yuening 《Meteorological and Environmental Research》 CAS 2016年第5期50-53,共4页
In the newly revised Environmental Protection Law of the People's Republic of China that has been implemented since January 1,2015,there is a lot of emphasis on environmental economic policies. In this paper,accor... In the newly revised Environmental Protection Law of the People's Republic of China that has been implemented since January 1,2015,there is a lot of emphasis on environmental economic policies. In this paper,according to the current situation of environmental pollution and protection in thermal power industry,it is proposed that based on the new environmental protection law,it is needed to study various environmental economic policies on thermal power industry and analyze the effects on environmental cost of thermal power enterprises at the macro level. At the micro level,it is necessary to control environmental cost of thermal power enterprises effectively,and establish a suitable environmental management system for environmental economic policies including environmental cost accounting and trading of emission rights,thereby improving environmental management level of thermal power enterprises. 展开更多
关键词 ENVIRONMENTAL PROTECTION LAW thermal power industry ENVIRONMENTAL ECONOMIC POLICIES china
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Response of Vegetation Cover to Climate Change and Influence of Dusty Weather in the Desertloess Transitional Zone of China
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作者 Yajun WANG 《Agricultural Science & Technology》 CAS 2013年第10期1526-1528,F0003,共4页
[Objective]This study aimed to analyze the relationships of the normalized difference vegetation index(NDVI)(1981-2006)in the desert-loess transitional zone of China with precipitation and temperature.[Method]The aver... [Objective]This study aimed to analyze the relationships of the normalized difference vegetation index(NDVI)(1981-2006)in the desert-loess transitional zone of China with precipitation and temperature.[Method]The average method and the correlation function were applied in this study.[Result]The results indicated that during the growing season NDVI was positively correlated with precipitation in the current month,last month and the month before last,especially the last month.NDVI mostly negatively correlated with temperature,especially the temperature in the last month,which shows that the higher temperature,the more adverse the conditions for vegetation growth.[Conclusion]NDVI from August to October clearly is one of the significant factors influencing dust storm weather in spring of the next year. 展开更多
关键词 Desert-loess transitional zone of china NDVI Climate change Dusty weather
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The application of metal-organic frameworks and their derivatives for lithium-ion capacitors
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作者 ZHAO Sha-sha ZHANG Xiong +5 位作者 LI Chen AN Ya-bin HU Tao WANG Kai SUN Xian-zhong MA Yan-wei 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期872-895,共24页
There is an urgent need for lithium-ion capacitors(LICs)that have both high energy and high power densities to meet the continuously growing energy storage demands.LICs effectively balance the high energy density of t... There is an urgent need for lithium-ion capacitors(LICs)that have both high energy and high power densities to meet the continuously growing energy storage demands.LICs effectively balance the high energy density of traditional rechargeable batteries with the superior power density and long life of supercapacitors(SCs).Nevertheless,the development of LICs is still hampered by limited kinetic processes and capacity mismatch between the cathode and anode.Metal-organic frameworks(MOFs)and their derivatives have received significant attention because of their extensive specific surface area,different pore structures and topologies,and customizable functional sites,making them compelling candidate materials for achieving high-performance LICs.MOF-derived carbons,known for their exceptional electronic conductivity and large surface area,provide improved charge storage and rapid ion transport.MOF-derived transition metal oxides contribute to high specific capacities and improved electrochemical stability.Additionally,MOF-derived metal compounds/carbons provide combined effects that increase both the capacitive and Faradaic reactions,leading to a superior overall performance.The review begins with an overview of the fundamental principles of LICs,followed by an exploration of synthesis strategies and ligand selection for MOF-based composite materials.It then analyzes the advantages of original MOFs and their derived materials,such as carbon materials and metal compounds,in enhancing LIC performance.Finally,the review discusses the major challenges faced by MOFs and their derivatives in LIC applications and offers future research directions and recommendations. 展开更多
关键词 Lithium-ion capacitors MOFS transition metal oxide Energy density power density
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A Special Report of Visit to Director Zhang Xiaolu of Department of Science &Technology and Environmental Protection, the State Power Corporation of China──Top Leveled Enterprise Must Possess Top Leveled Science & Technology Innovation Ability
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《Electricity》 2000年第2期30-36,共7页
关键词 A Special Report of Visit to Director Zhang Xiaolu of Innovation Department of Science power Corporation of china Technology Innovation Ability Technology and Environmental Protection top Leveled Enterprise Must Possess top Leveled Science the State ZHANG
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Transitivity Analysis of the Energy in China’s New Era
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作者 SHAN Ting WANG Yu 《Journal of Literature and Art Studies》 2024年第2期170-176,共7页
At present,with the steady development of the global economy,more and more countries begin to pay attention to the impact of ecological environment on economic development and human society,so the ecological environme... At present,with the steady development of the global economy,more and more countries begin to pay attention to the impact of ecological environment on economic development and human society,so the ecological environment has become a global issue that cannot be ignored in today’s era.Therefore,from the perspective of the ecological philosophy of Diversity&Harmony as well as Interaction&Co-existence,this paper will conduct ecological discourse analysis on the Energy in China’s New Era based on the transitivity system of systemic-functional grammar,and use the Corpus analysis software UAM Corpus Tool 3.3x to label and make statistics on the transitivity system,aiming to explore the distribution characteristics of the transitivity system in this white paper.Through the transitivity analysis of the white paper,this study helps readers to have a deeper understanding of the positive significance contained in the white paper.To a certain extent,it enables readers at home and abroad to understand China’s stance on energy issues and the positive image of China in energy ecology.It also awaken readers’awareness of environmental protection and acquire good habits of resource conservation to be in harmony between human and nature for sustainable development. 展开更多
关键词 TRANSITIVITY Ecological discourse analysis Energy in china’s new era
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Crust and upper mantle structures beneath Northeast China from receiver function studies 被引量:8
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作者 Zhen Guo Yuliang Cao +5 位作者 Xianguang Wang Y.John Chen Jieyuan Ning Weiguang He Youcai Tang Yongge Feng 《Earthquake Science》 2014年第3期265-275,共11页
P-wave and S-wave receiver function analyses have been performed along a profile consisted of 27 broadband seismic stations to image the crustal and upper mantle discontinuities across Northeast China. The results sho... P-wave and S-wave receiver function analyses have been performed along a profile consisted of 27 broadband seismic stations to image the crustal and upper mantle discontinuities across Northeast China. The results show that the average Moho depth varies from about 37 km beneath the Daxing'anling orogenic belt in the west to about 33 km beneath the Songliao Basin, and to about 35 km beneath the Changbai mountain region in the east. Our results reveal that the Moho is generally flat beneath the Daxing'anling region and a remarkable Moho offset (about 4 km) exists beneath the basin-mountain boundary, the Daxing'anling-Taihang Gravity Line. Beneath the Tanlu faults zone, which seperates the Songliao Basin and Changbai region, the Moho is uplift and the crustal thick- ness changes rapidly. We interpret this feature as that the Tanlu faults might deeply penetrate into the upper mantle, and facilitate the mantle upwelling along the faults during the Cenozoic era. The average depth of the lithosphereasthenosphere boundary (LAB) is - 80 km along the profile which is thinner than an average thickness of a continental lithosphere. The LAB shows an arc-like shape in the basin, with the shallowest part approximately beneath the center of the basin. The uplift LAB beneath the basin might be related to the extensive lithospheric stretching in the Mesozoic. In the mantle transition zone, a structurally complicated 660 km discontinuity with a maximum 35 km depression beneath the Changbai region is observed. The 35 km depression is roughly coincident with the location of the stagnant western pacific slab on top of the 660 km discontinuity revealed by the recent P wave tomography. 展开更多
关键词 Northeast china NCC - Receiver function Migration - CCP - Moho - LAB Mantle transition zone
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Preliminary Estimation of Paleoproductivity via TOC and Habitat Types:Which Method Is More Reliable?—A Case Study on the Ordovician-Silurian Transitional Black Shales of the Upper Yangtze Platform, South China 被引量:2
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作者 苏文博 王永标 +3 位作者 Bradley D Cramer Axel Munnecke 李志明 傅力浦 《Journal of China University of Geosciences》 SCIE CSCD 2008年第5期534-548,共15页
New total organic carbon (TOC) data from the two Ordovician-Silurian transitional graptolite-bearing black shale intervals, the Wufeng (五峰) Formation and the Longmaxi (龙马溪) Formation in Central Guizhou (... New total organic carbon (TOC) data from the two Ordovician-Silurian transitional graptolite-bearing black shale intervals, the Wufeng (五峰) Formation and the Longmaxi (龙马溪) Formation in Central Guizhou (贵州) and West Hubei (湖北), respectively, as well as previously reported TOC data from the same intervals in other places on the Yangtze platform of South China, have been used to produce an initial estimate of the primary paleoproductivity via a conventional inverse method (i.e., Rpp.inverse). The values of the Rpp.inverse are estimated to be 32 (43-21) gC/(m^2·a)(Wufeng Formation) and 21 (27-16) gC/(m^2·a) (Longmaxi Formation). Also, simultaneously, the habitat types (i.e., HT; cf., BA: benthic assemblage) and their temporal and spatial changes have been documented from the same succession, and an initial estimate of the primary paleoproductivity has been produced using a forward method (i.e., Rpp-forward) Beingbounded mainly by the peritidal to inner-shelf environment shelly-facies or mixed-facies successions with BA1 to BA3 faunas both at the top and the base, which indicates the habitat types from HT Ⅱ to HT Ⅲ2, the biohabitat type of the two graptolite-bearing black shale intervals can be limited to HT III to HT IV, corresponding to the inner shelf to the outer shelf, with depths from roughly 60 m to 200-300 m. Based on the current data from the South China Sea and the southern part of the East China Sea, values of Rpp-forward should be about 100 to 400 gC/(m^2·a). The difference in the results via the two methods suggests that paleoproductivity estimates from the geological strata need to be made cautiously, with particular attention paid to the paleogeographic setting, oxic-anoxic conditions, as also the preservation factor of organic carbon. 展开更多
关键词 primary productivity black shale toC habitat type (HT) Ordovician-Silurian transition South china.
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Porosity model and pore evolution of transitional shales:an example from the Southern North China Basin 被引量:5
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作者 Xiao-Guang Yang Shao-Bin Guo 《Petroleum Science》 SCIE CAS CSCD 2020年第6期1512-1526,共15页
The evolution of shale reservoirs is mainly related to two functions:mechanical compaction controlled by ground stress and chemical compaction controlled by thermal effect.Thermal simulation experiments were conducted... The evolution of shale reservoirs is mainly related to two functions:mechanical compaction controlled by ground stress and chemical compaction controlled by thermal effect.Thermal simulation experiments were conducted to simulate the chemical compaction of marine-continental transitional shale,and X-ray diffraction(XRD),CO2 adsorption,N2 adsorption and high-pressure mercury injection(MIP)were then used to characterize shale diagenesis and porosity.Moreover,simulations of mechanical compaction adhering to mathematical models were performed,and a shale compaction model was proposed considering clay content and kaolinite proportions.The advantage of this model is that the change in shale compressibility,which is caused by the transformation of clay minerals during thermal evolution,may be considered.The combination of the thermal simulation and compaction model may depict the interactions between chemical and mechanical compaction.Such interactions may then express the pore evolution of shale in actual conditions of formation.Accordingly,the obtained results demonstrated that shales having low kaolinite possess higher porosity at the same burial depth and clay mineral content,proving that other clay minerals such as illite-smectite mixed layers(I/S)and illite are conducive to the development of pores.Shales possessing a high clay mineral content have a higher porosity in shallow layers(<3500 m)and a lower porosity in deep layers(>3500 m).Both the amount and location of the increase in porosity differ at different geothermal gradients.High geothermal gradients favor the preservation of high porosity in shale at an appropriate Ro.The pore evolution of the marine-continental transitional shale is divided into five stages.Stage 2 possesses an Ro of 1.0%-1.6%and has high porosity along with a high specific surface area.Stage 3 has an Ro of 1.6%-2.0%and contains a higher porosity with a low specific surface area.Finally,Stage 4 has an Ro of 2.0%-2.9%with a low porosity and high specific surface area. 展开更多
关键词 thermal simulation Porosity model Pore evolution transitional shale Southern North china Basin Shanxi formation
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NEW RURAL SPACES: THE IMPACT OF RURAL INDUSTRIALIZATION ON RURAL-URBAN TRANSITION IN CHINA 被引量:1
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作者 MIAO Chang-hong(School of Environment and Planning Henan University Kaifeng 475001, P.R. China) 《Chinese Geographical Science》 SCIE CSCD 2000年第2期131-137,共7页
Since the 1980s, rural-urban transition has been becoming one of the most important aspects in China’s fast transformation from traditional to modern modes. From the perspective of change of rural space, this paper e... Since the 1980s, rural-urban transition has been becoming one of the most important aspects in China’s fast transformation from traditional to modern modes. From the perspective of change of rural space, this paper examines the impact of rural industrialization on the rural-urban transition. After an introduction to the issue of rural-urban transition in rural-urban continuum, a historical overview of the transformations of China’s rural space in economic, social and geographical structure is presented. This is followed by an analysis of regiotal uneven development among provinces in rural industrialization and rural-urban transition. It is concluded that the fast industrialization of rural area has brought on many radical transformations of rural space in China, especially on the formation of new rural economic, social and geographical spaces and the uneven development of rural-urban trgnsition among the eastern, central and westem areas. 展开更多
关键词 RURAL INDusTRIALIZATION rural-urban transition new RURAL space china
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