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China:Political, Social, and Economic Reforms from 1700s to the Present 认领
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作者 Connie Shum Christine E.Fogliasso Gladie Lui 《现代会计与审计:英文版》 2020年第1期19-30,共12页
Chinese social and economic history is both influenced by and,to a certain extent,married with Chinese political regimes.Various political dynasties from the past have each exercised significant control of Chinese soc... Chinese social and economic history is both influenced by and,to a certain extent,married with Chinese political regimes.Various political dynasties from the past have each exercised significant control of Chinese social and economic environments,and continue to exert influence even to the present day.Three of these influential periods include the Kang Qian Flourishing Age(1723-1796),the Qing Dynasty Decline(1800s-1912),and the People’s Republic of China Communist Control(1949-present).A review and in-depth examination of each regime helps to both understand where China is today and also how it is likely to evolve in the future. 展开更多
关键词 China REFORMS POLITICAL SOCIAL and ECONOMIC REFORMS in China China from 1700s to the PRESENT
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Science China Technological Sciences 2020年63卷第2期中文摘要 认领
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《中国科学:技术科学》 EI CSCD 北大核心 2020年第2期247-248,共2页
高能量密度材料的发展刘吉平,刘莉莉,刘晓波含能化合物的性能主要由密度、氧平衡、生成热、稳定性等构成,其中,密度是最重要的因素,因为密度决定爆压和爆速.高能量密度材料(HEDMs)的发展趋势之一是研究高氮的含能材料.氮含量高的化合物... 高能量密度材料的发展刘吉平,刘莉莉,刘晓波含能化合物的性能主要由密度、氧平衡、生成热、稳定性等构成,其中,密度是最重要的因素,因为密度决定爆压和爆速.高能量密度材料(HEDMs)的发展趋势之一是研究高氮的含能材料.氮含量高的化合物不像硝基或硝酸酯那样仅仅依靠碳骨架的分子内氧化释放能量,它可以从形成热中获得大量能量.由于含能材料的反应不是核反应,因此研发出的新的含能材料应该具备优良性能,应能满足做功威力大、对外界作用不敏感、能量释放率高、使用寿命长、相容性良好、生物性能优异、毒性低、吸潮性低,同时还要确保装药对勤务以及战场环境的安全性,满足军事和民用的要求. 展开更多
关键词 高能量密度材料 含能离子盐 SCIENCE China TECHNOLOGICAL SCIENCES 2020 含能材料 压力脉动 空化流动 中文摘要 China
中国中世纪气候异常期温度的多尺度变化特征及区域差异 认领
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作者 郝志新 吴茂炜 +2 位作者 刘洋 张学珍 郑景云 《地理学报:英文版》 SCIE CSCD 2020年第1期119-130,共12页
The Medieval Climate Anomaly(MCA,AD950-1250)is the most recent warm period lasting for several hundred years and is regarded as a reference scenario when studying the impact of and adaptation to global and regional wa... The Medieval Climate Anomaly(MCA,AD950-1250)is the most recent warm period lasting for several hundred years and is regarded as a reference scenario when studying the impact of and adaptation to global and regional warming.In this study,we investigated the characteristics of temperature variations on decadal-centennial scales during the MCA for four regions(Northeast,Northwest,Central-east,and Tibetan Plateau)in China,based on high-resolution temperature reconstructions and related warm-cold records from historical documents.The ensemble empirical mode decomposition method is used to analyze the time series.The results showed that for China as a whole,the longest warm period during the last 2000 years occurred in the 10th-13th centuries,although there were multi-decadal cold intervals in the middle to late 12th century.However,in the beginning and ending decades,warm peaks and phases on the decadal scale of the MCA for different regions were not consistent with each other.On the inter-decadal scale,regional temperature variations were similar from 950 to 1130;moreover,their amplitudes became smaller,and the phases did not agree well from 1130 to 1250.On the multi-decadal to centennial scale,all four regions began to warm in the early 10th century and experienced two cold intervals during the MCA.However,the Northwest and Central-east China were in step with each other while the warm periods in the Northeast China and Tibetan Plateau ended about 40-50 years earlier.On the multi-centennial scale,the mean temperature difference between the MCA and Little Ice Age was significant in Northeast and Central-east China but not in the Northwest China and Tibetan Plateau.Compared to the mean temperature of the 20th century,a comparable warmth in the MCA was found in the Central-east China,but there was a little cooling in Northeast China;meanwhile,there were significantly lower temperatures in Northwest China and Tibetan Plateau. 展开更多
关键词 China MULTI-SCALE VARIATIONS temperature MEDIEVAL CLIMATE ANOMALY
抓住市场机遇 拥抱行业变革——中国国际事故车行业高峰论坛(IBIS China 2019)成功举办 认领
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作者 张淑珍 《汽车维修与保养》 2020年第1期80-81,共2页
2019年12月4日,中国国际事故车行业高峰论坛(简称IBIS China 2019)作为Automechanika Shanghai重要的同期活动在上海举行。来自中国事故车行业各领域的专家代表130余人齐聚一堂,聆听"拥抱变革"这一主题下,面对当前复杂多变的... 2019年12月4日,中国国际事故车行业高峰论坛(简称IBIS China 2019)作为Automechanika Shanghai重要的同期活动在上海举行。来自中国事故车行业各领域的专家代表130余人齐聚一堂,聆听"拥抱变革"这一主题下,面对当前复杂多变的市场竞争环境,各方行业专家独特的观点态度及全新主张。本次会议吸引了来自保险公司、汽车制造商、OEM制造商和维修企业的代表,在一整天的会议中,代表着国际事故车行业领先水平的10余名企业代表及行业精英,与参会代表们共同分享了各自擅长领域的知识经验及深刻见解。 展开更多
关键词 事故车 IBIS China 2019 China 高峰论坛
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The Impact of Chinese Trade and Investment on West African Economic Growth: A Spatial Econometrics Approach 认领
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作者 Hua Wilfried Serge Koffi 《应用科学(英文)》 2020年第4期142-153,共12页
This paper has studied the West African region or Economic Community of West African States (ECOWAS) which includes fifteen countries and its relationship with China. Three countries (Cote d’Ivoire, Ghana, and Nigeri... This paper has studied the West African region or Economic Community of West African States (ECOWAS) which includes fifteen countries and its relationship with China. Three countries (Cote d’Ivoire, Ghana, and Nigeria) of the fifteen countries which are economically representative in the west African region to represent the overall-region were studied. Therefore, the objective of this study is to investigate the spatial effect of Chinese trade and investment on the economic growth of West Africa. The study focuses on the period from 1960-2014 using the dynamic panel data approach and spatial autoregressive approach for the econometric analysis of this topic. Empirically, the results show that trade openness with China has a positive impact on the neighboring countries of the region, especially for those who share the same border. Chinese investment is vital to the region’s economic growth as the results show that one dollar investment increase from China to the host country increases the economic growth in the neighboring countries by 0.328%. 展开更多
关键词 China Trade Investment WEST Africa ECONOMIC Community of WEST AFRICAN STATES (ECOWAS) ECONOMIC Growth
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Mapping Urban Networks through Inter-Firm Linkages: The Case of Listed Companies in Yangtze River Delta, China 认领
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作者 Yizhen Zhang Weidong Cao Kun Zhang 《地球科学和环境保护期刊(英文)》 2020年第3期23-36,共14页
Recently, literature on urban network research from the perspective of ?rm networks has been increasing. This research mainly used data from the headquarters and branches of all 2581 listed manufacturing companies in ... Recently, literature on urban network research from the perspective of ?rm networks has been increasing. This research mainly used data from the headquarters and branches of all 2581 listed manufacturing companies in the Yangtze River Delta from 1990 to 2017, and studied the urban network through an interlocking network model that quantifies the links between enterprises. The results showed that the spatial distribution of listed manufacturing industries in the Yangtze River Delta was relatively concentrated, and cities such as Shanghai, Nanjing, and Hangzhou were hot spots for the spatial distribution of listed manufacturing industries. However, Fuyang, Suqian, Chizhou, Lishui and other network edge cities were less distributed in manufacturing. The urban network of the Yangtze River Delta has significant hierarchical characteristics. The urban network of the Yangtze River Delta presents a multi-center network development mode with Shanghai as the center and Nanjing, Hangzhou, and Hefei as the sub-centers. Moreover, we found that the development of inter-city connections in the Yangtze River Delta was driven by network mechanisms of priority attachment and path dependence. The radiating capacity and agglomeration capacity of cities in the Yangtze River Delta have a strong polarization characteristic. The core cities such as Shanghai, Nanjing, Hangzhou, and Hefei have much higher network radiation capabilities than network aggregation capabilities. However, other non-core cities and network edge cities have weak network radiation capabilities, and mainly accept network radiation from core cities. It enriches the research of urban networks based on real inter-?rm connections, and provides ideas for the wider regional study and the combination of econometric techniques and social network analysis. 展开更多
关键词 Urban Networks INTERLOCKING Network Model YANGTZE River DELTA China
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Measuring and Forecasting Chinese Domestic Supply and Demand for Grain Sorghum 认领
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作者 Shuguo Yang Jaime Malaga 《农业科学(英文)》 2020年第1期71-87,共17页
In the past 5 years, the use of sorghum as substitutes for corn for feed in China has increased rapidly. Most of the recent growth of demand in sorghum has mainly been met by imported sorghum. Because sorghum is a min... In the past 5 years, the use of sorghum as substitutes for corn for feed in China has increased rapidly. Most of the recent growth of demand in sorghum has mainly been met by imported sorghum. Because sorghum is a minor crop and only shares a very small proportion of the grain production in China, few studies have examined domestic demand and supply of sorghum in China. Both China’s producers and other sorghum import countries can benefit from forecasts of China’s domestic supply and demand for sorghum. 展开更多
关键词 SORGHUM China DEMAND and Supply
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中国主体功能区空间结构的多尺度解析 认领
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作者 王亚飞 樊杰 《地理学报:英文版》 SCIE CSCD 2020年第2期197-211,共15页
The spatial structures of China’s Major Function Zoning are important constraining indicators in all types of spatial planning and key parameters for accurately downscaling major functions.Taking the proportion of ur... The spatial structures of China’s Major Function Zoning are important constraining indicators in all types of spatial planning and key parameters for accurately downscaling major functions.Taking the proportion of urbanization zones,agricultural development zones and ecological security zones as the basic parameter,this paper explores the spatial structures of major function zoning at different scales using spatial statistics,spatial modeling and landscape metrics methods.The results show:First,major function zones have spatial gradient structures,which are prominently represented by latitudinal and longitudinal gradients,a coastal distance gradient,and an eastern-central-western gradient.Second,the pole-axis system structure and core-periphery structure exist at provincial scales.The general principle of the pole-axis structure is that as one moves along the distance axis,the proportion of urbanization zones decreases and the proportion of ecological security zones increases.This also means that the proportion of different function zones has a ring-shaped spatial differentiation principle with distance from the core.Third,there is a spatial mosaic structure at the city and county scale.This spatial mosaic structure has features of both spatial heterogeneity,such as agglomeration and dispersion,as well as of mutual,adjacent topological correlation and spatial proximity.The results of this study contribute to scientific knowledge on major function zones and the principles of spatial organization,and it acts as an important reference for China’s integrated geographical zoning. 展开更多
关键词 China major function ZONING MULTI-SCALE SPATIAL gradient pole-axis CORE-PERIPHERY SPATIAL MOSAIC
中国地貌区划理论与分区体系 认领
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作者 王楠 程维明 +2 位作者 王白雪 刘樯漪 周成虎 《地理学报:英文版》 SCIE CSCD 2020年第2期212-232,共21页
Geomorphological regionalization(geomor-region)and geomorphological type(geomor-type)classification are two core components in the geomorphologic research.Although remarkable achievements have been made in the study o... Geomorphological regionalization(geomor-region)and geomorphological type(geomor-type)classification are two core components in the geomorphologic research.Although remarkable achievements have been made in the study of geomor-region,many deficiencies still exist,such as the inconsistency of landform indicators,the small quantity of division orders,disparities of geomorphological characteristics,differences of mapping results,and the small scale of zoning maps.Requirements for improved national geomor-regions are therefore needed for the purpose of an enhanced national geo-information system.Based on theories of geomor-region in China including plate tectonics,crustal features,endogenic and exogenic forced geomorphological features,and regional differentiations of geomor-type,a three-order(major-region,sub-region,and small-region)research program on China’s geomor-regions is proposed on the basis of previous 2013 geomor-region system.The major contents of the new geomor-region scheme are:(1)principles of the national multi-order geomor-regions;(2)hierarchical indicator systems of geomor-regions including characteristics of the terrain ladder under the control of tectonic setting,combinations of regional macro-form types,combinations of endogenic and exogenic forces and basic types of morphology,combinations of regional morphological types,and combinations of regional micro-morphological types;(3)naming rules and coding methods of geomor-regions;and(4)precise positioning techniques and methods of multi-order geomor-region divisions based on multi-source data.Using the new geomor-region theory and division methodology,the partition of national three-order geomor-regions of China was successfully constructed.The geomor-region system divided China into six first-order major-regions,36 second-order sub-regions,and 136 third-order small-regions.In addition,a database and management information system of the national geomor-regions were established.This research has an important guiding significance for promoting the d 展开更多
关键词 geomorphological REGIONALIZATION geomorphological TYPES HIERARCHICAL SYSTEM China
新时期中国与墨西哥农产品贸易合作新动态及前景 认领
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作者 郑国富 《农业展望》 2020年第2期107-111,116共6页
2013年,中国和墨西哥将两国关系提升至全面战略伙伴关系,增进农产品贸易合作是两国经贸关系发展的新亮点、新方向。2001—2018年,中国与墨西哥农产品贸易合作成效显著,规模持续扩大,总量持续增长,贸易地位攀升,产品种类拓展。结合对中... 2013年,中国和墨西哥将两国关系提升至全面战略伙伴关系,增进农产品贸易合作是两国经贸关系发展的新亮点、新方向。2001—2018年,中国与墨西哥农产品贸易合作成效显著,规模持续扩大,总量持续增长,贸易地位攀升,产品种类拓展。结合对中墨两国贸易结合度、产业内贸易、贸易互补性的分析发现,两国在农产品贸易合作中存在双边贸易总体规模有限、地位低微、结构不平衡、种类集中且产品单一,贸易关联度低且互补性弱,产业内贸易不足且层次低下等主要问题。新时期,中墨两国将以“一带一路”倡议与“中拉论坛”为平台,增进政治互信,完善农业合作机制,增进贸易互补融合,加速自贸协定谈判,推动农业领域“五通”建设,实现双边农产品贸易可持续发展,增进两国利益与人民福祉。 展开更多
关键词 中国 墨西哥 农产品贸易 贸易关联度 贸易互补性 “一带一路” 中拉论坛
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Firm-Level TFP Growth in the Chinese Automobile Industry 认领
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作者 Xiaoheng Zhang Xu Tian 《中国经济学前沿:英文版》 2020年第1期103-123,共21页
China has been the world’s largest automobile producer since 2009,but it still lags behind other countries in terms of productivity. Based on theNational Bureau of Statistics of China (NBSC) firm-level data and the i... China has been the world’s largest automobile producer since 2009,but it still lags behind other countries in terms of productivity. Based on theNational Bureau of Statistics of China (NBSC) firm-level data and the improvedapproach proposed by Ackerberg et al. (2015), this paper investigates thecontribution of total factor productivity (TFP) growth to the Chinese automobileindustry and evaluates the impact of firm entry and exit on TFP growth. Theempirical results show that the TFP of the Chinese automobile industry grows at10.7% per year. Joint venture and foreign-owned firms have a significantly higherTFP growth rate than others. Large-scale firms have a higher TFP growth rate thando small-scale firms, but the latter have caught up after 2004. Moreover, the entryof new firms and exit of old firms significantly improve the aggregate TFP growthrate. 展开更多
关键词 automobile industry total factor productivity(TFP)growth rate FIRM entry and EXIT ACF model OWNERSHIP structure China National BUREAU of Statistics of China(NBSC)database FIRM size
China’s alfalfa market and imports: Development, trends, and potential impacts of the U.S.-China trade dispute and retaliations 认领
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作者 Qingbin WANG ZOU Yang 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第4期1149-1158,共10页
This study examines the development and trends of China’s alfalfa market and imports, identifies key factors for the rapid increase in China’s alfalfa imports, and discusses potential impacts of the U.S.-China trade... This study examines the development and trends of China’s alfalfa market and imports, identifies key factors for the rapid increase in China’s alfalfa imports, and discusses potential impacts of the U.S.-China trade dispute and retaliations on the alfalfa markets and trade in both nations. China’s rapid transition toward larger-scale commercial dairy production, with enhanced feed and cost management as well as quality and safety control, and its limited resources for high-quality alfalfa production are key factors for the dramatic increase in its alfalfa imports, from 19 601 metric tons in 2008 to 1.38 million metric tons(mmt) in 2018. While the United States dominated China’s alfalfa imports with an average share of 97.01% from 2007 to 2017, the share dropped to 83.76% in 2018 and 63.28% in January 2019 due to the trade dispute and retaliations started in 2018. China will likely remain a large importer of alfalfa because of both its growing demand and the comparative advantages of imported alfalfa in quality and price, but the imports from the United States will be highly affected by the ongoing trade dispute and negotiations. China is also expected to make more efforts to reduce its dependence on U.S. alfalfa through increased investment in domestic alfalfa production and identification of alternative sources of alfalfa and other hay imports. 展开更多
关键词 China’s ALFALFA IMPORTS U.S.alfalfa EXPORTS dairy industrialization U.S.-China trade DISPUTE and retaliations GM-free standards
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农户的非农就业如何影响中国的土地流转? 认领
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作者 王佳月 辛良杰 王亚辉 《地理学报:英文版》 SCIE CSCD 2020年第3期378-400,共23页
To clarify the impact of non-agricultural employment on rural land circulation in China,we built logit models using the Chinese Household Income Project 2013 dataset,which includes 18,948 household samples over 15 pro... To clarify the impact of non-agricultural employment on rural land circulation in China,we built logit models using the Chinese Household Income Project 2013 dataset,which includes 18,948 household samples over 15 provinces,126 cities and 234 counties of China in 2013.We use the proportion of non-agricultural income,the proportion of non-agricultural laborers and non-agricultural fixed operating assets to reflect the degree of the households’dependence on agriculture,the degree of the households’laborers committed to non-agricultural employment and the stability of non-agricultural employment,respectively.The results show that the stability of non-agricultural employment is an important reason for farmers to transfer out their land,and an increase in non-agricultural income is the fundamental reason.The proportion of non-agricultural assets has the greatest impact on the decision to transfer land,followed by the proportion of non-agricultural income.Per unit increase in the non-agricultural income ratio has a stronger effect on the transfer-out decision than it does on the transfer-in decision,which is a 0.09 increase of the probability of transfer-out the land and a 0.07 decrease of the probability of transfer-in the land.In terms of regional differences,when considering the impact of non-agricultural employment on the land transfer-out decision,the impacts of non-agricultural income and labor force are the greatest in the Central region.The impact of non-agricultural assets is the greatest in the Eastern region.For the Eastern region,the decision to transfer out land is mainly affected by non-agricultural assets and the non-agricultural labor force,and the decision to transfer in land is mainly affected by non-agricultural assets.In the Central and Western regions,the decision to transfer out land is mainly affected by non-agricultural assets,non-agricultural income and the non-agricultural labor force,in that order.The decision to transfer in land in the Central region is not significantly affected by non- 展开更多
关键词 farmers’non-agricultural employment rural land circulation moderate scale management China CHIP2013 dataset
民国时期中国的公共体育场衰退成因探骊 认领
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作者 邵天逸 《首都体育学院学报》 CSSCI 北大核心 2020年第3期274-278,共5页
民国时期,中国的公共体育场的出现,对推广群众体育起到了一定的作用。运用文献资料法、历史研究法等,分析认为,民国时期中国的公共体育场功能是发展群众体育、增进成年民众健康、发挥教育功能、改善社会风气,但实际上,这些功能并非实现... 民国时期,中国的公共体育场的出现,对推广群众体育起到了一定的作用。运用文献资料法、历史研究法等,分析认为,民国时期中国的公共体育场功能是发展群众体育、增进成年民众健康、发挥教育功能、改善社会风气,但实际上,这些功能并非实现,且逐渐走向了衰退。其衰退的根本原因在于:民国时期,体育健身项目并非成年民众普遍崇尚的娱乐形式;公共体育场举办的活动多为非体育性活动;同时还受到了经费有限、群众体育提倡力度不足、体育专业人才匮乏等因素影响。 展开更多
关键词 中国 民国时期 公共体育场 衰退成因 群众体育
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1978-2018年中国旅游业发展的地理格局 认领
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作者 张城铭 翁时秀 保继刚 《地理学报:英文版》 SCIE CSCD 2020年第3期487-507,共21页
Since the reform and opening-up policy launched in 1978,the number of inbound tourists increased from 1.8 million in 1978 to 139.5 million in 2017,and that of domestic tourists increased from 344 million in 1991 to 5 ... Since the reform and opening-up policy launched in 1978,the number of inbound tourists increased from 1.8 million in 1978 to 139.5 million in 2017,and that of domestic tourists increased from 344 million in 1991 to 5 billion in 2017.This article conducts research on how the geographical pattern of China’s tourism has evolved in the last four decades on the national-scale and regional-scale,for rare studies before could focus on such an extended date and utilize inbound and domestic tourism data simultaneously.Grounded on viable datasets and multiple vibrant data analysis approaches(including the Gini coefficient,primacy index analysis,hot spot analysis and Pearson correlation analysis),this article unpacks triple vital realities.(1)The overall geographical pattern of China’s tourism development can arguably summarize as“high in the eastern and low in the western part,high in the southern and low in the northern part.”Meanwhile,China’s inbound tourism has long shown a pattern of polarized distribution;While,domestic tourism has experienced a shift from the polarized distribution to the equilibrium distribution.(2)According to the features and characteristics,China's tourism development can be divided into four stages.They are precisely the initial modern tourism stage(1978–1988),the domestic tourism cultivating stage(1989–1996),the rapid development stage(1997–2007)and the new normal stage(2008–present).(3)This article also identified multiple factors underlying the inbound and domestic tourism development in China,including policies,management systems,tourism demand,tourist attractions,economic level,consumption level,industrial development,investment status,traffic conditions,accommodation services,intermediary services and degree of openness. 展开更多
关键词 reform and opening-up tourism development spatial pattern development stage influencing factor China
21世纪以来中国对巴基斯坦的“救灾援助”研究 认领
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作者 闫红果 《新疆大学学报:哲学.人文社会科学版》 CSSCI 2020年第3期45-54,共10页
巴基斯坦是中南亚地区灾害多发的国家,在历次自然灾害与社会性灾害中,中国均鼎力救援。文章在界定“救灾援助”概念的基础上,重点围绕2005年大地震、2010年特大洪水、社会民生问题等领域,初步梳理了21世纪以来中国对巴基斯坦“救灾援助... 巴基斯坦是中南亚地区灾害多发的国家,在历次自然灾害与社会性灾害中,中国均鼎力救援。文章在界定“救灾援助”概念的基础上,重点围绕2005年大地震、2010年特大洪水、社会民生问题等领域,初步梳理了21世纪以来中国对巴基斯坦“救灾援助”的总体状况。研究发现,中国的救援行动突出“救”的主题,利他性强,积极效应明显。同时,为了应对参与救援的民间力量相对薄弱、救援行为易受到西方的误解和挤压等问题,中国应加强对民间救援力量的整合,积极构建国际话语权,开展救灾防灾领域的合作以助力解决巴基斯坦的民生问题。 展开更多
关键词 “救灾援助” 中国 巴基斯坦 中巴关系 中南亚
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Crustal density structures and isostasy beneath the Western North China craton,Trans-North China Orogen,and surrounding regions 认领
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作者 Min Gao Djordje Grujic Qiu-Ming Cheng 《地学前缘:英文版》 SCIE CAS CSCD 2020年第2期569-580,共12页
To determine the lateral and vertical variations in crustal structure and their influence on the seismicity of the Western North China Craton,the Trans-North China Orogen,and the surrounding regions,the wavelet multi-... To determine the lateral and vertical variations in crustal structure and their influence on the seismicity of the Western North China Craton,the Trans-North China Orogen,and the surrounding regions,the wavelet multi-scale structures,Moho depth,crustal density structures,and isostatic state are modelled using Bouguer gravity anomaly data,topography,and earthquake focal mechanisms.We obtained homogeneous crustal densities and deviations of<1 km between the crustal thicknesses estimated from the isostatic model and those inverted from the Bouguer gravity anomalies in the Ordos Block,the Inner Mongolia Suture Zone,the Sichuan Basin,and the Jizhong Depression.These results provide new evidence for relatively simple and stable continental crustal structures,and indicate that these regions will remain stable in both the vertical and lateral directions.The Hetao Graben,Yinchuan Graben,Weihe Basin,and Shanxi graben system have heterogeneous crustal densities and are isostatically over-compensated.In contrast,the crust beneath the Yinshan Uplift,Lvliang Uplift,and northern and central Taihang Uplift is thin and under-compensated.The heterogeneous crustal densities and non-isostatic state beneath the Tibetan Plateau and Qinling Central China Orogen indicate that these two blocks are unstable in the vertical and lateral directions.Although Cenozoic deformation of the North China Craton is thought to be driven by lithospheric stresses related to the India-Eurasia collision and Pacific slab retreat in South East Asia,we suggest that gravitational potential energy created by the heterogeneous crustal structure modulates these first-order forces.The results of this study could constrain the causes of seismicity in systems surrounding the Ordos Block. 展开更多
关键词 Western North China CRATON Trans-North China OROGEN Bouguer gravity anomaly CRUSTAL density structure Gravitational potential energy
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海洋考古视域下环南中国海国家的海贸互动——以中国为中心 认领
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作者 王丽敏 《中州大学学报》 2020年第3期73-77,88共6页
中国海洋考古经历了从无到有曲折而高效的发展历程,南中国海域是中国乃至世界海洋考古的重心。海洋考古在南中国海域发现、发掘的一批批不同时期、诸多类型的水下遗存,见证了中国与环南中国海国家在舟船和航海技术、航路和港市建设、船... 中国海洋考古经历了从无到有曲折而高效的发展历程,南中国海域是中国乃至世界海洋考古的重心。海洋考古在南中国海域发现、发掘的一批批不同时期、诸多类型的水下遗存,见证了中国与环南中国海国家在舟船和航海技术、航路和港市建设、船货与海商贸易领域漫长而密切的交往历史。中国海洋考古的未来发展需要实现实践和理论的良性互动、海洋考古学和其他学科的有效整合。加强中国和国际社会对海洋文化遗产的保护、发掘和利用,为进一步研究海上丝绸之路、探索海洋文明、解读海洋历史开辟广阔空间。 展开更多
关键词 海洋考古 海贸 中国 环南中国海
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中美价值观差异下高校有效课堂教学改革策略分析 认领
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作者 李盼 《山西科技》 2020年第1期106-109,112共5页
中美价值观的差异导致了中美课堂教学模式存在着较大的差异,美国的高等教育水平在世界上名列前茅,中国需要学习其先进的经验来发展自己的高等教育事业。以有效开展课堂教学,提高课堂教学质量为切入点,对价值观差异下的中美高校课堂教学... 中美价值观的差异导致了中美课堂教学模式存在着较大的差异,美国的高等教育水平在世界上名列前茅,中国需要学习其先进的经验来发展自己的高等教育事业。以有效开展课堂教学,提高课堂教学质量为切入点,对价值观差异下的中美高校课堂教学进行对比,提出中国高校开展有效课堂教学改革的路径,并以JSCY学校为例,介绍了有效课堂实施的具体流程以及认证标准,以期对中国高等教育的改革起到一定的参考作用。 展开更多
关键词 高校 有效课堂 价值观差异 中国 美国
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我国中深层煤炭地下气化商业化路径 认领
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作者 孔令峰 张军贤 +3 位作者 李华启 朱兴珊 赵晨晖 徐加放 《天然气工业》 EI CAS CSCD 北大核心 2020年第4期156-165,共10页
全球已开展的煤炭地下气化(UCG)矿场试验绝大多数都是在浅煤层进行的,受环境保护因素的制约很大;而中深煤层UCG项目环保优势突出、发展前景好于浅煤层,但选址因素却更加复杂、地下工程难度更大。为了实现我国中深层UCG技术的商业化,在... 全球已开展的煤炭地下气化(UCG)矿场试验绝大多数都是在浅煤层进行的,受环境保护因素的制约很大;而中深煤层UCG项目环保优势突出、发展前景好于浅煤层,但选址因素却更加复杂、地下工程难度更大。为了实现我国中深层UCG技术的商业化,在调研国内外UCG技术发展现状的基础上,分析归纳了UCG技术商业化所面临的主要问题,进而探析了中深层UCG项目商业化的路径。现有的问题包括:①浅煤层气化存在着较大的环保风险;②中深煤层气化工程难度较大;③在目前的技术水平条件下,UCG项目投资的经济性较差;④选址和系统配套等条件对于UCG项目的竞争力影响较大。研究结果表明:①从投资经济性的角度来考虑,中深层UCG项目单个地下气化单元(UGU)设计需要实现较高的日产气量和累计产气量,同时也需要较长的气化通道来控制大量的煤炭资源,还要解决好气化通道堵塞和破坏失效等问题;②中深层UCG属于资金和技术密集型项目,项目选址不仅要考虑地下条件因素,而且还要充分考虑产品市场和公用工程系统配套等条件。结论认为,我国可以优先考虑在新疆准东、哈密、三塘湖,内蒙古鄂尔多斯、二连、海拉尔等煤炭资源条件优越的油气产区建设UCG试验基地、部署先导试验和商业项目。这样做能够发挥与油气产业链的协同效益,或将是推动中深层UCG技术研发试验和商业化的最佳路径之一。 展开更多
关键词 中国 煤炭地下气化(UCG) 地下气化单元(UGU) 可控后退注入点(CRIP) 平行水平井组 分支水平井 “斜梯形”地下气化单元 集束连续油管 柔性可燃油管
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