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Changes of China’s Status in the Global System and Its Influencing Factors:A Multiple Contact Networks Perspective
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作者 LIU Jian LIU Jibin +2 位作者 YANG Qingshan CAI Sikai LIU Jie 《Chinese Geographical Science》 SCIE CSCD 2024年第2期265-279,共15页
Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on cou... Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on country comparisons or institutional en-vironment.In today’s networked era in which the global economy,trade,personnel,and information are closely connected,studies on China’s global position and its status changes and influencing factors in multiple contact networks are still insufficient.In this study,from the perspective of diverse global contact networks,we constructed economic,cultural,and political influence indices to explore the changes and influencing factors on China’s status in the global system from 2005 to 2018.The results show that during the study period,China’s global influence in the fields of economic ties,cultural exchanges,and political contacts increased significantly,but its influ-ence in the fields of cultural exchanges and political contacts lagged far economic ties.The pattern of China’s economic influence on various economies around the world has shown a transformation from an‘upright pyramid’to an‘inverted pyramid’structure.The proportion of these economies in low-influence zones has decreased from more than 60%in 2005 to less than 20%in 2018.China’s cultural and political influence on various economies around the world has increased significantly;however,for the former,the percentage of high-influence areas is still less than 20%,whereas for the latter the percentage of these economies in medium-and high-influence areas is still less than 50%.Analyses such as a scatter plot matrix show that geographical proximity,economic globalization,close cooperation with developing countries,and a proactive and peaceful foreign policy are important factors in improving China’s status in the diverse global network system. 展开更多
关键词 global system economic ties cultural exchanges political contacts multiple contact networks chinas status
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Understanding the Global Identification with China’s Stories: A Cross-Cultural Perspective
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作者 Fu Chun Deng Da 《Contemporary Social Sciences》 2024年第1期46-57,共12页
Cross-cultural storytelling is a primary way for humankind to seek mutual recognition of value orientations between cultures,which facilitates the ability to jointly address the problems of human existence in the cont... Cross-cultural storytelling is a primary way for humankind to seek mutual recognition of value orientations between cultures,which facilitates the ability to jointly address the problems of human existence in the context of globalization.In this study,we conducted an interview survey of 6,130 respondents who were college students or graduates from 107 countries.The results show that there were a number of cross-cultural values embodied in China’s stories seen by the respondents as part of a common vision for the future of humankind and widely identified guidance on collaborative responses to global challenges.These cross-cultural values are common prosperity,ecological harmony,individual-collective integration,the urgency of global peace,as well as respect for multicultural and indigenous development paths. 展开更多
关键词 chinas stories global identification cross-cultural communication
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Spatio-temporal Variation Characteristics of Extreme Climate Events and Their Teleconnections to Large-scale Ocean-atmospheric Circulation Patterns in Huaihe River Basin,China During 1959–2019
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作者 YAO Tian ZHAO Qiang +6 位作者 WU Chuanhao HU Xiaonong XIA Chuan'an WANG Xuan SANG Guoqiang LIU Jian WANG Haijun 《Chinese Geographical Science》 SCIE CSCD 2024年第1期118-134,共17页
Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of... Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of 40 meteorological stations and nine monthly large-scale ocean-atmospheric circulation indices data during 1959–2019,we present an assessment of the spatial and temporal variations of extreme temperature and precipitation events in the HRB using nine extreme climate indices,and analyze the teleconnection relationship between extreme climate indices and large-scale ocean-atmospheric circulation indices.The results show that warm extreme indices show a significant(P < 0.05) increasing trend,while cold extreme indices(except for cold spell duration) and diurnal temperature range(DTR) show a significant decreasing trend.Furthermore,all extreme temperature indices show significant mutations during 1959-2019.Spatially,a stronger warming trend occurs in eastern HRB than western HRB,while maximum 5-d precipitation(Rx5day) and rainstorm days(R25) show an increasing trend in the southern,central,and northwestern regions of HRB.Arctic oscillation(AO),Atlantic multidecadal oscillation(AMO),and East Atlantic/Western Russia(EA/WR) have a stronger correlation with extreme climate indices compared to other circulation indices.AO and AMO(EA/WR) exhibit a significant(P < 0.05) negative(positive)correlation with frost days and diurnal temperature range.Extreme warm events are strongly correlated with the variability of AMO and EA/WR in most parts of HRB,while extreme cold events are closely related to the variability of AO and AMO in eastern HRB.In contrast,AMO,AO,and EA/WR show limited impacts on extreme precipitation events in most parts of HRB. 展开更多
关键词 extreme climate indices sen’s slope variation mutation test atmospheric circulation indices Pearson’s correlation analysis Huaihe River Basin(HRB) china
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Evolution and Governance of the Structure of Marine Economic Networks in China’s Coastal Areas: Based on Sea-related A-share Listed Companies
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作者 LI Bo CAO Gai 《Chinese Geographical Science》 SCIE CSCD 2024年第5期899-916,共18页
Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linka... Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linkages,the importance of marine economic net-work research is beginning to emerge.The construction of the marine economic network in China’s coastal areas is necessary to change the flow of land and sea resources and optimize regional marine economic development.Employing data from headquarters and branches of sea-related A-share listed enterprises to construct the marine economic network in China,we use social network analysis(SNA)to discuss the characteristics of its evolution as of 2010,2015,and 2020 and its governance.The following results were obtained.1)In terms of topological characteristics,the scale of the marine economic network in China’s coastal areas has accelerated and expan-ded,and the connections have become increasingly close;thus,this development has complex network characteristics.2)In terms of spatial structure,the intensity of the connection fluctuates and does not form stable development support;the group structure gradually becomes clear,but the overall pattern is fragmented;there are spatial differences in marine economic agglomeration radiation;the radi-ation effect of the eastern marine economic circle is obvious;and the polarization effect of northern and southern marine economic circles is significant.On this basis,we construct a framework for the governance of a marine economic network with the market,the government,and industry as the three governing bodies.By clarifying the driving factors and building objectives of marine economic network construction,this study aims to foster the high-quality development of China’s marine economy. 展开更多
关键词 marine economic network sea-related A-share listed companies social network analysis(sNA) network governance chinas coastal areas
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Entrepreneurial Spirit for China in the New Era and Strategies for Cultivation
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作者 Xu Yuanhua He Jun +1 位作者 Sun Zao Li Xiaoke 《China Economist》 2024年第5期48-59,共12页
What type of entrepreneurial spirit is needed for China’s new era,and how can we unlock its innovation potential?Answers to these questions will unleash vital forces to drive China’s high-quality economic developmen... What type of entrepreneurial spirit is needed for China’s new era,and how can we unlock its innovation potential?Answers to these questions will unleash vital forces to drive China’s high-quality economic development.After reviewing the theories,dimensions,features,and limitations of the entrepreneurial spirit in the Western context,we concluded that the entrepreneurial spirit in China’s new era,which is characterized by patriotism,innovation,trustworthiness,adherence to the law,fulfillment of social responsibilities,and a global horizon,has overcome the limitations that come with self-interested entrepreneurship in the context of Western economics.This is a major step forward in the development of theories on entrepreneurial spirit.In the development context of the new era,this paper argues that the entrepreneurial spirit should become an important force at the individual level to implement the new development concept,foster the new development paradigm,and promote high-quality development in the new stage.This paper provides answers to the question of what type of entrepreneurial spirit China’s new era requires.Finally,this paper presents basic strategies for cultivating entrepreneurial spirit in the context of China’s new era,emphasizing the importance to promote the healthy growth of young entrepreneurs,ensure their business autonomy,develop a multi-tiered capital market,implement the factor market reforms,improve the business climate,and accelerate the digital transition. 展开更多
关键词 Context of chinas new era context of Western economics entrepreneurial spirit high-quality development cultivation strategy
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GDI and GSI: China’s New Propositions for Global Governance
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作者 Ouyang Xiangying 《China Economist》 2024年第5期107-116,共10页
In the post-pandemic era,the global economic and security landscapes are fraught with complexities and uncertainties.Among them,four risk flashpoints merit attention:Certain countries are raising interest rates to sub... In the post-pandemic era,the global economic and security landscapes are fraught with complexities and uncertainties.Among them,four risk flashpoints merit attention:Certain countries are raising interest rates to subdue inflation,despite their already high levels of debt;the bulk commodities market is experiencing volatility,leading to global turbulence and change;trade protectionism is at the forefront of major-power rivalry in political and economic spheres;and regional security crises are compounding international tensions.Behind those flashpoints are contradictions that obstruct world peace and progress,including development imbalances,governance gaps,and structural tensions in global security.In the face of uncertainties,it is crucial for China to seize strategic opportunities and transform crises into favorable situations.China has launched the Global Development Initiative(GDI)and the Global Security Initiative(GSI)to contribute to global prosperity and security.The two initiatives demonstrate China’s commitment to addressing global deficits in peace,development,security,and governance. 展开更多
关键词 Global Development Initiative(GDI) Global security Initiative(GsI) chinas approach to global governance Ukraine crisis china-Russia relationship
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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 chinas new era
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Human Rights and Development:China's Contributions Based on a Larger Concept of Human Rights
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作者 WU Wenyang LI Rong 《The Journal of Human Rights》 2024年第4期776-801,共26页
The Western liberal view of global governance can no longer effectively address the challenges facing the world today or respond to the demands of developing countries in the fields of human rights and development.Mea... The Western liberal view of global governance can no longer effectively address the challenges facing the world today or respond to the demands of developing countries in the fields of human rights and development.Meanwhile,the United Nations human rights and development agenda also has its limitations.Against such a backdrop,China's path of human rights development has avoided the trap of human rights confrontation and the clash of civilizations.It has set an example of complementarity and positive interaction between human rights and development by unifying collective human rights with individual human rights and integrating the universality and particularity of human rights.Xi Jinping,general secretary of the Communist Party of China(CPC)Central Committee,delivered a speech at the 37th group study session of the Political Bureau of the CPC Central Committee on China's Path of Human Rights Development.This elevated China's human rights development to a new historical height.Practice has proved that China's concept and path of human rights in the new era have not only effectively promoted the development of its human rights cause,but also contributed Chinese wisdom to the global cause of human rights and development with a larger concept of human rights.Under the framework of the concept of building a community with a shared future for mankind,the Belt and Road Initiative,and the Global Development Initiative,China has contributed to enhancing the discourse power of developing countries in human rights and building a fairer,more just,more reasonable and more inclusive system for global human rights governance. 展开更多
关键词 human rights and development a larger concept of human rights global human rights governance chinas path of human rights development
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Historical review and reflections on the participation of acupuncture and moxibustion in the treatment of epidemics in the People’s Republic of China (from 1950 until now)
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作者 Xiong Xiao 《History & Philosophy of Medicine》 2024年第3期1-5,共5页
Since the establishment of the People’s Republic of China, both the Communist Party and the government have placed great emphasis on the advancement of traditional Chinese medicine. Acupuncture and moxibustion have b... Since the establishment of the People’s Republic of China, both the Communist Party and the government have placed great emphasis on the advancement of traditional Chinese medicine. Acupuncture and moxibustion have been actively involved in combating major epidemics such as malaria, schistosomiasis, and COVID-19. This article conducts a historical review of these three significant cases to elucidate how the acupuncture community has effectively utilized its unique advantages and characteristics through theoretical discussions, clinical practices, experimental research, as well as receiving administrative leadership and political support from the Communist Party of China and government. We provide an objective evaluation of their effectiveness while summarizing historical experiences to serve as a reference for future utilization of acupuncture and moxibustion therapy in epidemic relief efforts. Additionally, propose four suggestions: strengthening Party leadership and enhancing political support;timely summarization of experiences to establish programs and systems;deepening scientific research by integrating experimental findings with clinical practice;focusing on public awareness campaigns and education to solidify grassroots foundations. 展开更多
关键词 acupuncture and moxibustion the People’s Republic of china EPIDEMICs MALARIA sCHIsTOsOMIAsIs COVID-19
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Analysis of New Senior English for China Student’s Book 1
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作者 Xia Qian 《语言与文化研究》 2024年第4期128-132,共5页
This article will firstly discuss the context overview of English teaching and learning in China. Under thiscircumstance, a problematic element will be examined of the New Senior English for China Student’s Book 1 an... This article will firstly discuss the context overview of English teaching and learning in China. Under thiscircumstance, a problematic element will be examined of the New Senior English for China Student’s Book 1 and critical appraisal ofhow this element relates to other elements of curriculum development will be analyzed. The recommended changes and demonstrationmechanisms for evaluating the changes are put forward in the last two parts. 展开更多
关键词 New senior English for china student’s Book 1 Assessment Critical appraisal Curriculum development CHANGEs
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宽负荷下切圆燃煤锅炉H_(2)S分布特性的数值模拟 被引量:1
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作者 邓磊 袁茂博 +3 位作者 杨家辉 韩磊 姜家豪 车得福 《煤炭学报》 EI CAS CSCD 北大核心 2024年第6期2887-2895,共9页
锅炉采用空气分级燃烧降低NO_(x)排放的同时也提高了主燃区H_(2)S体积分数。炉墙壁面过高的H_(2)S体积分数是加剧水冷壁高温腐蚀的重要因素。为保障新能源并网发电,大型燃煤机组灵活调峰的需求增加,不同负荷下的水冷壁近壁面H_(2)S分布... 锅炉采用空气分级燃烧降低NO_(x)排放的同时也提高了主燃区H_(2)S体积分数。炉墙壁面过高的H_(2)S体积分数是加剧水冷壁高温腐蚀的重要因素。为保障新能源并网发电,大型燃煤机组灵活调峰的需求增加,不同负荷下的水冷壁近壁面H_(2)S分布特性值得关注。通过正交试验分析了切圆燃煤锅炉运行参数对水冷壁近壁面H_(2)S体积分数分布的影响。选取一台超临界600 MW切圆燃煤锅炉建立数值模型,设计L_(16)(4^(5))正交工况,覆盖100%BMCR、75%THA,50%THA以及35%BMCR四种负荷。建立了自定义SO_(x)生成模型以确定燃料硫的析出和转化路径,模型包含多表面反应子模型以描述焦炭与O_(2)/CO_(2)/H_(2)O等3种气体的异相反应,并确定焦炭气化反应消耗量占总消耗量的比例,进而对炉膛H_(2)S空间分布进行了模拟计算。研究表明,近壁面高体积分数H_(2)S区域主要位于投运燃烧器层中最下层燃烧器以下以及最上层燃烧器以上至SOFA层之间,烟气切圆沿炉膛高度增加逐渐增大是造成后一区域H_(2)S体积分数较高的重要原因。35%BMCR负荷下水冷壁重点区域的H_(2)S平均体积分数为364μL/L,明显低于其他负荷。锅炉运行参数对重点区域H_(2)S体积分数影响程度的排序为:锅炉负荷>一次风率>主燃区空气过量系数>假想切圆直径>燃烧器竖直摆角。 展开更多
关键词 切圆燃煤锅炉 宽负荷 H2s分布 正交分析 数值模拟
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基于改进YOLOX-S的轻量化煤矸石检测方法研究 被引量:1
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作者 高如新 杜亚博 常嘉浩 《河南理工大学学报(自然科学版)》 CAS 北大核心 2024年第4期133-140,共8页
目的 为了探索基于现有机器视觉煤矸石检测方法的模型参数量、计算量对检测速度和嵌入式设备的影响,方法 提出一种基于改进的无锚框YOLOX-S轻量化煤矸石检测模型。为使模型能提取更真实的煤矸石特征信息,收集分选现场煤矸石样本,保证实... 目的 为了探索基于现有机器视觉煤矸石检测方法的模型参数量、计算量对检测速度和嵌入式设备的影响,方法 提出一种基于改进的无锚框YOLOX-S轻量化煤矸石检测模型。为使模型能提取更真实的煤矸石特征信息,收集分选现场煤矸石样本,保证实际环境下的煤矸石检测效果,适应实际生产环境。结合CSPNet,将输入的特征图分割成两个分支,实现更丰富的梯度组合,同时减少模型计算量;之后在其中一条分支使用Ghost轻量化卷积,通过少量常规卷积生成一组特征图,达到初次减少计算量和参数量的效果,然后在此特征图基础上经过简单线性变化操作,生成一组新的特征图,将两组特征图进行融合,降低对计算资源需求的同时,也达到了常规卷积相同的特征提取效果;引入LeakyReLU激活函数减弱模型梯度消失的影响,提取更深更多的特征信息;最后融合两个分支特征,保证较高的检测精度,提升模型检测速度。采用CIOU Loss(complete IOU loss)优化目标边界框回归损失函数,使模型回归损失收敛更快,提高模型目标定位能力。结果 与原模型相比,本文改进模型在保证较高的平均精度均值90.51%情况下,模型参数减少47%,计算量减少49%,检测速度达到50帧/s。结论 轻量化煤矸石检测模型使智能化煤矸石检测在实际生产环境中具有一定的应用前景。 展开更多
关键词 煤矸石检测 YOLOX-s 轻量化 目标定位 检测速度
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基于程函面波成像的华北克拉通岩石圈三维高分辨率S波速度结构研究
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作者 钟世军 吴建平 +2 位作者 司政亚 朱红彬 王薇 《地震学报》 CSCD 北大核心 2024年第4期578-599,共22页
利用“中国地震科学台阵探测”项目Ⅱ期和Ⅲ期的流动地震台站以及中国区域地震台网中的部分固定台站的观测资料,采用程函面波成像方法获得了华北克拉通及周边区域10—120 s周期的瑞雷面波相速度分布和高分辨率的三维S波速度结构,并基于... 利用“中国地震科学台阵探测”项目Ⅱ期和Ⅲ期的流动地震台站以及中国区域地震台网中的部分固定台站的观测资料,采用程函面波成像方法获得了华北克拉通及周边区域10—120 s周期的瑞雷面波相速度分布和高分辨率的三维S波速度结构,并基于该速度模型估算了岩石圈厚度分布。结果显示,华北克拉通内部岩石圈厚度除了存在“西厚东薄”的一级分布特征外,还存在一些更小尺度的差异,包括鄂尔多斯地块内部岩石圈“南厚北薄”、鄂尔多斯地块周缘断陷带岩石圈显著的不均匀减薄以及燕山构造带与其南侧华北平原之间的显著差异等。山西断陷带北部与南部地区上地幔浅部(<100 km)存在不同程度的低速异常,它们被中部的高速异常区所分隔。在150 km以下深度从太行山南缘向北至山西断陷北缘存在一条NNE向展布的显著低速异常带,表明上地幔浅部南北部的低速异常在深部相连。结合已有的其它成像结果,我们推测这些低速异常起源于更深处(>200 km),并与由太平洋俯冲板块的滞留脱水导致的上地幔热物质上涌和小尺度地幔对流等密切相关。燕山构造带与华北平原的岩石圈结构存在明显差异,前者遭受的岩石圈破坏改造程度明显弱于后者,张家口—渤海地震带位于这两种不同壳幔结构的过渡带,地震活动较强,我们认为深部结构和热作用的显著差异,以及青藏高原远场挤压效应的共同作用是导致该区地震活动较强的主要原因。 展开更多
关键词 华北克拉通 程函面波成像 s 波速度 低速异常 岩石圈厚度 显著差异
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Intelligent and ecological coal mining as well as clean utilization technology in China: Review and prospects 被引量:51
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作者 Guofa Wang Yongxiang Xu Huaiwei Ren 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第2期161-169,共9页
Coal is an essential fossil fuel in China; however, coal mining and its utilization are being under the increasing pressure from ecological and environmental protection. Therefore, the consulting project "Technic... Coal is an essential fossil fuel in China; however, coal mining and its utilization are being under the increasing pressure from ecological and environmental protection. Therefore, the consulting project "Technical Revolution in Ecological and Efficient Coal Mining and Utilization & Intelligence and Diverse Coordination of Coal-based Energy System," initiated by Chinese Academy of Engineering, puts forward three stages(3.0, 4.0 and 5.0) of China's coal industry development strategy. Aimed at "reduced staff,ultra-low ecological damage, and emission level near to natural gas," breakthroughs should be achieved in the following three key technologies during the China Coal Industry 3.0 stage(2016–2025): including intelligent coal mining, ecological mining, ultra-low emission and environmental protection. This paper focuses on the development trends of the China Coal Industry 3.0 and its support for China Coal Industry 4.0 and 5.0 is analyzed and prospected as well, which may offer technical assistance and strategy orientation for realizing the transformation from traditional coal energy to clean energy. 展开更多
关键词 INTELLIGENT MINING ECOLOGICAL MINING CLEAN utilization Environmental protection chinas coal industry
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Rare Earth Element Geochemistry of Late Palaeozoic Coals in North China 被引量:15
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作者 HUANG Wenhui YANG Qi +2 位作者 TANG Dazhen TANG Xiuyi ZHAO Zhigen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第1期74-83,共10页
Abstract: Instrumental Neutron Activation Analysis (INAA) was done to determine the abundances of rare earth elements (REE) of 58 samples of Late Palaeozoic Carboniferous-Permian coals and related rocks in North China... Abstract: Instrumental Neutron Activation Analysis (INAA) was done to determine the abundances of rare earth elements (REE) of 58 samples of Late Palaeozoic Carboniferous-Permian coals and related rocks in North China. Detailed study of REE geochemistry shows that the ?REE of most coals studied in this paper is in a normal range between 30×10?6 and 80×10?6 with a mean of 56×10?6. The REE in the Taiyuan Formation in the northern part of North China are much richer than those in the southern part. This is due to the shorter distance to the source area in the north. Moreover, the ?REE is in positive correlation to coal ash, especially closely related to the content of clay minerals <2 μm in size. This reveals that most REE were carried by terrigenous clastic materials, especially fine clay minerals. In the coals the light REE (LREE) are much richer than the heavy REE (HREE), and the LREE/HREE ratio in coals generally varies from 2 to 8. The LREE/HREE ratio of high-ash, low-sulphur coals is higher than that of low-ash, high-sulphur coals, and is even higher in the roof and floor rocks, reaching 12 with the highest (up to 21) in pyrite concretions, which shows that the HREE have a stronger affinity to organic matter in a reducing environment influenced by seawater. Furthermore, Eu is generally depleted in coals. The REE chondrite-normalized distribution patterns are very similar in coals of the whole of North China. From the REE geochemical characteristics it can be concluded that during the formation of Late Palaeozoic Carboniferous-Permian coals in North China, the supply of terrigeneous materials remained quite stable. The ?REE in low-ash, high-sulphur coals is relatively low and the REE are mainly carried by fine-grained minerals and organic matter and a certain percentage of REE are adsorbed by organic matter; while the ?REE in high-ash, low-sulphur coals is higher and the REE are mainly present in detritus. The ?REE of magmatism-influenced coals is the highest, which suggests that the introduction of magmatic substances may increase the ?REE, thus causing the REE distribution patterns to show an abnormal feature. Moreover, some harmful elements such as U, W and As usually increase when the coals are influenced by magmatism. 展开更多
关键词 Late Palaeozoic coal REE GEOCHEMIsTRY North china
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东北地区土地覆被格局变化模拟:基于CLUE-S和Markov-CA模型的对比分析 被引量:2
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作者 王端睿 毛德华 +2 位作者 王宗明 相恒星 冯凯东 《地理科学》 CSSCI CSCD 北大核心 2024年第2期329-339,共11页
研究以遥感解译的东北地区2000年、2010年、2015年的土地覆被变化为基础,充分考虑自然和社会因素对土地覆被变化的影响,分别通过CLUE-S模型和Markov-CA模型对东北地区2015年和2030年土地覆被格局进行模拟,研究结果表明:通过与遥感解译的... 研究以遥感解译的东北地区2000年、2010年、2015年的土地覆被变化为基础,充分考虑自然和社会因素对土地覆被变化的影响,分别通过CLUE-S模型和Markov-CA模型对东北地区2015年和2030年土地覆被格局进行模拟,研究结果表明:通过与遥感解译的2015年实际土地覆被类型数据对比验证,CLUE-S模型和Markov-CA模型模拟结果的总体Kappa指数分别为0.9700和0.9649,结果表明2种模型的模拟结果较为理想,CLUE-S模型的模拟精度较Markov-CA模型更高。2015—2030年东北地区草地、耕地、湿地、其他用地和水体面积呈现下降趋势,林地、人工表面面积呈现增加趋势,人地关系越发紧张。东北地区作为生态环境相对脆弱的区域需警惕不可持续的土地覆被变化,需权衡生态保护、粮食增加与基础设施建设的用地需求和协调发展。 展开更多
关键词 CLUE-s模型 Markov-CA模型 土地利用/覆被变化 空间模拟 东北地区
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Coalbed Methane-bearing Characteristics and Reservoir Physical Properties of Principal Target Areas in North China 被引量:15
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作者 TANGShuheng SUNShenglin +1 位作者 HAODuohu TANGDazhen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期724-728,共5页
The coalbed methane (CBM) resources in North China amounts up to 60% of total resources in China. North China is the most important CBM accumulation area in China. The coal beds of the Upper Paleozoic Taiyuan and Shan... The coalbed methane (CBM) resources in North China amounts up to 60% of total resources in China. North China is the most important CBM accumulation area in China. The coal beds of the Upper Paleozoic Taiyuan and Shanxi formations have a stable distribution. The coal reservoir of target areas such as Jincheng, Yanquan-Shouyang, Hancheng, Liulin, etc. have good CBM-bearing characteristics, high permeability and appropriate reservoir pressure, and these areas are the preferred target areas of CBM developing in China. The coal reservoirs of Wupu, Sanjiaobei, Lu'an, Xinmi, Anyang-Hebi, Jiaozuo, Xinggong and Huainan also have as good CBM-bearing characteristics, but the physical properties of coal reservoirs vary observably. So, further work should be taken to search for districts with high pressure, high permeability and good CBM-bearing characteristics. Crustal stresses have severe influence on the permeability of coal reservoirs in North China. From west to east, the crustal stress gradient increases, while the coal reservoirs permeability decreases. 展开更多
关键词 coalbed methane (CBM) coal reservoir physical property crustal stress North china
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Sequence Stratigraphy of the Jurassic Coal Measures in Northwestern China 被引量:12
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作者 WANG Tong SHAO Longyi +2 位作者 TIAN Ye LU Jing WANG Wenlong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第3期769-778,共10页
The sequence stratigraphy of the Jurassic coal measures of northwestern China has been studied based on data from outcrop and borehole sections. Because of the geological background and the diversity of basin types, s... The sequence stratigraphy of the Jurassic coal measures of northwestern China has been studied based on data from outcrop and borehole sections. Because of the geological background and the diversity of basin types, such as isochronisms of coal seams and recognition of key sequence boundaries, it is rare to summarize and correlate sequence structure and framework. The types and recognition characteristics of the sequence boundaries of the Jurassic coal measures are revealed by comparing climatic characteristics, structural styles and the base level cycle. A total of five third-order sequences and 15 systems tracts have been subdivided and the sequence stratigraphic framework has been reconstructed confirming that the thick coals accumulated in the late stage of transgression system tracts of sequence I (SQ I) and sequence III (SQ III). This idea is of important academic significance for instructing coal resources exploration, and enhancing geological effects of prospecting engineering. It is also of practical significance for guaranteeing construction of the large-scale coal production base in northwestern China, accelerating the westward development of the coal industry stratagem. 展开更多
关键词 depositional system sequence stratigraphic characteristics Jurassic (Hettangian–Callovian) coal basins northwestern china
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A Carbon Isotopic Stratigraphic Pattern of the Late Palaeozoic Coals in the North China Platform and Its Palaeoclimatic Implications 被引量:7
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作者 ZHANG Hong SHEN Guanglong HE Zonglian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第1期111-119,共9页
This paper gives the stable carbon isotopic data in coals from the Late Namurian to Kazanian stages in the Serteng Mt., Xishan and Huainan coalfields of the North China Platform. Its stratigraphic pattern shows that s... This paper gives the stable carbon isotopic data in coals from the Late Namurian to Kazanian stages in the Serteng Mt., Xishan and Huainan coalfields of the North China Platform. Its stratigraphic pattern shows that several isotopic shifts are apparent, and the large δ13C negative shifts (approximately 2.5 to 3.0 %%) occurred during the Stephanian, Artinskian and Kazanian are observed in three Permo-Carboniferous coalfields. Those negative shifts are neither related to the coal rank and coal macerals, nor caused by the variety of peat-forming plants. The general decrease in the δ13C values of the Stephanian, Artinskian and Kazanian coals is consistent with an overall decrease in the δ13C values of ambient atmospheric CO2 and/or a relative increase in atmospheric Pco2 during the coal-forming periods. Therefore the authors postulate that the oxidation of peat, and the δ13C-depleted CO2 flux into the atmosphere during the above stages may have contributed to coeval palaeoclimatic warming by way of the greenhouse effect. 展开更多
关键词 carbon isotope coal PALAEOCLIMATE Late Palaeozoic the North china Platform
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Distribution Characteristics of Sulfur and the Main Harmful Trace Elements in China's Coal 被引量:5
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作者 TANG Shuheng SUN Shenglin +2 位作者 QIN Yong JIANG Yaofa WANG Wenfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期722-730,共9页
To promote the rational development and use of clean coal resources in China, data on the regional and age distribution of sulfur, arsenic and other harmful elements in Chinese coal was broadly collected, tested for c... To promote the rational development and use of clean coal resources in China, data on the regional and age distribution of sulfur, arsenic and other harmful elements in Chinese coal was broadly collected, tested for content, and analyzed. Coal in northwestern China is characterized by low to extremely low levels of sulfur; the coal of the Taiyuan Formation in northern China mainly has high-sulfur content; that of the Shanxi Formation is mainly characterized by low sulfur coal; and the Late Permian coal in southern China has overall higher sulfur content; other regions have low sulfur coal. The average content of harmful trace elements in the bulk of China's coal is similar to the corresponding content in the coal of the North America and the rest of the world, whereas the content of various elements (Hg, Sb and Se) is different in magnitude to the corresponding percentage in the crust. The average content of the elements Cr, Se, Co, Be, U, Br in Late Permian coal in S China ranks first in the country whereas the average content of Hg and CI in the coals of Late Carboniferous to Early Permian age in N China are the highest. The average content of Mn in Early and Middle Jurassic coal is higher in NW China. The high content of harmful elements in some coal should cause particular concern both in the development and utilization of coal. 展开更多
关键词 coal sULFUR harmful trace elements distribution patterns ENVIRONMENT china
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