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Eurasia Continental Bridge——An Important Link of the Coordinated Development between China's Eastern,Central and Western Regions
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作者 Zhao Ming Li Zhukun 《China's Foreign Trade》 1996年第10期42-42,共1页
The new Eurasia Continental Bridgeruns from East China to Central andWest China, crossing 11 provincesand regions, namely Jiangsu, Shandong,Hubei, Anhui, Shaanxi, Gansu, Shanxi,Sichuan, Qinghai, Xinjiang and Ningxia.T... The new Eurasia Continental Bridgeruns from East China to Central andWest China, crossing 11 provincesand regions, namely Jiangsu, Shandong,Hubei, Anhui, Shaanxi, Gansu, Shanxi,Sichuan, Qinghai, Xinjiang and Ningxia.The total area is 3.6 million sq km and thepopulation is about 300 million, accountingfor a third and a quarter of the whole countryrespectively. The area is very rich in naturalresources, so it is called an "Economic goldbelt" and "Gold corridor". Aerial remote-control survey indicates that along thecontinental bridge from Lianyungang to theAla Mountains within China’s boundary, 展开更多
关键词 area In An Important Link of the Coordinated Development between China’s eastern central and western regions Eurasia Continental Bridge
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The Spatial-Temporal Distribution Patterns of Dyke Swarms in Central Asia and their Tectonic Significance: Case Studies in Eastern Tianshan and Western Junggar 被引量:1
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作者 FENG Qianwen LI Jinyi LIU Jianfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期152-153,共2页
Dykes are a special kind of intrusive rocks which were formed by deep magma intruded into the existing brittle fractures in the crust.Dykes swarms in different tectonic environments are very significant to re-construc... Dykes are a special kind of intrusive rocks which were formed by deep magma intruded into the existing brittle fractures in the crust.Dykes swarms in different tectonic environments are very significant to re-construct the 展开更多
关键词 deep Asia Case Studies in eastern Tianshan and western Junggar The Spatial-Temporal Distribution Patterns of Dyke Swarms in central Asia and their Tectonic Significance
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Division of the Eastern,Central and Western China
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《China Population Today》 2000年第Z1期3-3,共1页
关键词 Division of the eastern central and western China
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Comparative Assessment of the Proximate and Mineral Composition of <i>Cucumis sativus</i>L. and <i>Solanum aethiopicum</i>L. Fruit Samples Grown in South Eastern and North Central Regions of Nigeria Respectively
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作者 H. C. Okeke O. Okeke +2 位作者 K. O. Nwanya C. R. Offor C. C. Aniobi 《Natural Resources》 2021年第8期237-249,共13页
<span style="font-family:""><span style="font-family:Verdana;">Studies were carried out to comparatively assess the proximate and mineral composition of </span><i><s... <span style="font-family:""><span style="font-family:Verdana;">Studies were carried out to comparatively assess the proximate and mineral composition of </span><i><span style="font-family:Verdana;">Solanum aethiopicum </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">and </span><i><span style="font-family:Verdana;">Cucumis</span></i> <i><span style="font-family:Verdana;">sativus</span></i><span style="font-family:Verdana;"> L. fruit samples grown in the South Eastern and North Central regions of Nigeria respectively, following standard analytical procedures and instrumentation. The mineral elements (Na, K, Zn and Ca) were determined using atomic absorption spectrophotometer after wet digestion of the samples while the proximate parameters</span><i> </i><span style="font-family:Verdana;">(ash content, moisture content, crude fibre content, crude protein content, crude fat content and carbohydrate content) were determined in accordance with standard analytical procedures. The mean range of the moisture, crude fibre, crude protein, crude fat, ash and carbohydrate contents in the </span><i><span style="font-family:Verdana;">S. aethiopicum </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">fruit samples grown in the North Central and South Eastern regions of Nigeria were 72</span></span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;">49</span><span style="font-family:Verdana;"> -</span><span style="font-family:Verdana;"> 88</span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;">23, 2.15</span><span style="font-family:""> </span><span style="font-family:Verdana;">- 3.67, 1.31</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">- 1.85, 0.43 - 0.76, 0.51 - 0.84 and 3.18% - 5.72% respectively. Additionally, the moisture, crude fibre, crude protein, crude fat, ash and carbohydrate contents in the </span><i><span style="font-family:Verdana;">Cucumis sativus </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">fruit</span><i> </i><span style="font-family:Verdana;">samples grown in the South Eastern and North Central regions of Nigeria, had mean range of values of 93.60 - 98.76, 0.53 - 0.77, 2.14 - 2.84, 0.29 </span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 0.46, 0.90 </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 1.14 and 3.88% </span><span style="font-family:Verdana;">-</span><span style="font-family:""><span style="font-family:Verdana;"> 4.66% respectively. The range of mean values of Na, K, Zn and Ca in the </span><i><span style="font-family:Verdana;">S. aethiopicum </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">fruit samples from the South Eastern and North Central regions of Nigeria were 0.36 - 0.57, 1.92 - 2.80, 0.84 - 1.01 and 0.43 - 0.61 μg/g respectively. Also, Na, K, Zn and Ca</span><i> </i><span style="font-family:Verdana;">had mean range of values of 1.36 </span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 4.08, 10.16 - 13.09, 0.45 - 0.66 and 5.85 - 9.3</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">μg/g respectively in the </span><i><span style="font-family:Verdana;">C. sativus </span></i><span style="font-family:Verdana;">L. fruit samples grown in the South Eastern and North Central regions in Nigeria. The levels of the determined proximate of parameters</span><i> </i><span style="font-family:Verdana;">and mineral elements in the studied fruit samples from the investigated regions of Nigeria were statistically significant. This therefore indicates that the geographical locations where these fruit samples grew could have significantly impacted on their nutrient content levels. The levels of the determined proximate</span><i> </i><span style="font-family:Verdana;">parameters from the selected regions of Nigeria show</span></span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;"> that consumption of the fruit samples (</span><i><span style="font-family:Verdana;">S aethiopicum </span></i><span style="font-family:Verdana;">L. and</span><i><span style="font-family:Verdana;"> C. sativus </span></i><span style="font-family:Verdana;">L.)</span><i> </i><span style="font-family:Verdana;">especially regularly, would help supply the essential nutrients and minerals required for a healthy living. 展开更多
关键词 Solanum aethiopicum L. Cucumis sativus L. Proximate Parameters Mineral Elements South eastern region and North central region
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Comparative Assessment of the Phytochemical and Selected Heavy Metal Levels in <i>Cucumis sativus</i>L. and <i>Solanum aethiopicum</i>L. Fruit Sample Grown in South Eastern and North Central Regions of Nigeria Respectively
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作者 C. C. Aniobi O. Okeke +2 位作者 E. Ezeh H. C. Okeke K. O. Nwanya 《Natural Resources》 2021年第8期223-236,共14页
<span style="font-family:""><span style="font-family:Verdana;">Studies were carried out to comparatively assess the phytochemical and heavy metal levels in </span><i>&l... <span style="font-family:""><span style="font-family:Verdana;">Studies were carried out to comparatively assess the phytochemical and heavy metal levels in </span><i><span style="font-family:Verdana;">Solanum aethiopicum </span></i><span style="font-family:Verdana;">L. and </span><i><span style="font-family:Verdana;">Cucumis sativus </span></i><span style="font-family:Verdana;">L. fruit samples grown in the South Eastern and North Central regions of Nigeria respectively using standard analytical procedures and instrumentation. The fruit samples were assayed for selected heavy metals (Pb, Cd and Cu) using atomic absorption spectrophotometer after wet digestion of the samples. The five detected phytochemicals (flavonoids, alkaloids, terpenoids, saponins and glycosides) were present at varying amounts in the investigated fruit samples from the South Eastern and North Central regions of Nigeria. The range of mean values of flavonoids, terpenoids, saponins and glycosides in the </span><i><span style="font-family:Verdana;">S. aethiopicum </span></i><span style="font-family:Verdana;">L. fruit samples from the two studied regions were 0.50 - 0.57, 0.53 - 1.26, 0.44 - 0.78, 1.12 - 1.93 and 0.40 - 0.50 mg/g respectively. The range of mean values of flavonoids, alkaloids, terpenoids, saponins and glycosides in the </span><i><span style="font-family:Verdana;">C. sativus </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">fruit samples from the two studied regions of Nigeria were 1.27 - 1.69, 0.53 - 0.55, 0.96 - 1.51, 0.41 - 0.83 and 0.90 - 1.74 mg/g respectively. The range of mean vales of Pb, Cd, and Cu in the </span><i><span style="font-family:Verdana;">S. aethiopicum </span></i><span style="font-family:Verdana;">L. fruit samples from the two studied regions were 0.15 - 0.24, 0 - 0.01, 0.78 - 1.12 μg/g respectively. 0.31 - 0.40, 0.02 - 0.05 and 0.62 -</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">0.96 μg/g were the range of mean values of Pb, Cd and Cu</span><i> </i><span style="font-family:Verdana;">respectively in the </span><i><span style="font-family:Verdana;">C. sativus </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">fruit samples from the two studied regions of Nigeria. Of the three investigated heavy metals, only Cd was at toxic levels in the </span><i><span style="font-family:Verdana;">C. sativus </span></i><span style="font-family:Verdana;">L. fruit samples from the South Eastern and North Central regions of Nigeria. This is therefore a health concern to the fruit consumers that includes these fruits in their habitual daily fruit diets. Although the therapeutic and pharmaceutical benefits that </span></span><span style="font-family:Verdana;">would</span><span style="font-family:Verdana;"> be derived from consuming</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> the investigated fruit samples ha</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> been shown in this study, there is therefore a possible risk of undue exposure to environmental pollutants such as heavy metal, especially through growing these fruits in polluted soils resulting from unwholesome anthropogenic practices. For fruit consumers to derive maximum health benefits from consuming these fruits, pollutants like heavy metals must be at non-toxic levels and this can only be achieved by ensuring that these fruits samples are grown and harvested in environments with less anthropogenic activities. 展开更多
关键词 Cucumis sativus L. Solanum aethiopicum L. Phytochemicals and Heavy Met-als North central region and South eastern region
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Analysis of Externality of Rural Labor Force Flow in Central and Western Regions of China and Benefit Compensation 被引量:1
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作者 Xin LI Haijing HU 《Asian Agricultural Research》 2013年第9期64-67,共4页
According to the theories of institutional economics and development economics,the positive and negative externality of rural labor force flowing from central and western regions and into eastern regions of China were... According to the theories of institutional economics and development economics,the positive and negative externality of rural labor force flowing from central and western regions and into eastern regions of China were analyzed,and then it was proposed that it is necessary to positive externality,rather than take"household register"measures to solve the problem simply. 展开更多
关键词 RURAL LABOR force FLOW EXTERNALITY central and wes
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Historical experience in the elimination of visceral leishmaniasis in the plain region of Eastern and Central China 被引量:15
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作者 Li-Ren Guan Zhong-Xing Wu 《Infectious Diseases of Poverty》 SCIE 2014年第1期81-91,80,共12页
Visceral leishmaniasis(VL)(kala-azar)was most seriously prevalent in the plain regions of eight provinces/municipalities in the eastern and central parts of China.In the early 1950s,the number of counties/cities endem... Visceral leishmaniasis(VL)(kala-azar)was most seriously prevalent in the plain regions of eight provinces/municipalities in the eastern and central parts of China.In the early 1950s,the number of counties/cities endemic for VL and the number of cases in the plain regions accounted for 60%and 80%,respectively,of the total numbers in the entire country.By implementing comprehensive control measures,including treatment of patients for eliminating the source of infection and spraying insecticide in endemic villages to kill sandflies,VL transmission has been brought under control in this region by the early 1960s,and no new infected cases have been found since 1983,achieving the goal of eliminating VL. 展开更多
关键词 Visceral leishmaniasis ELIMINATION Plain region eastern and central China
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China's Problems between "Eastern, Western, Southern, Northern and Central China" and the Strategy of "Sustainable Development
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作者 何祚庥 《World Economy & China》 SCIE 1997年第1期15-23,32,共10页
关键词 and the Strategy of Northern and central China Sustainable Development eastern western SOUTHERN OO China’s Problems between
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Research on central village selection in western underdeveloped region:a case study of Lidian Town,Jingning County,Gansu Province,China
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作者 Lili Ma Shuang An 《Chinese Journal of Population,Resources and Environment》 2016年第3期174-181,共8页
Central village selection is the priority of small town construction.Depending on the development potential analysis,classification analysis,and quantitative and qualitative analysis,this article systematically propos... Central village selection is the priority of small town construction.Depending on the development potential analysis,classification analysis,and quantitative and qualitative analysis,this article systematically proposes the specific methods of central village selection and also constructs the indicator system used in central village selection in small towns of western underdeveloped region in China.The article also puts forward ideas and methods for selection of central village in the western underdeveloped region through an empirical research on Lidian Town,Jingning County,Gansu Province.In the final part,suggestions and recommendations on how to develop central village for Lidian Town are made. 展开更多
关键词 Small town construction selection of central village indicator system western underdeveloped region
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An Evaluation on the Effects of the Policy of the Great Campaign of Western Development of China in the First 10 Years Based on the Kuznets Regional Inverted-U Theory
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作者 Huan Zheng Xingming Fang 《Chinese Business Review》 2013年第10期661-672,共12页
In order to reduce the regional differentials or narrow the gap in economic development between eastern and western areas and prevent the intensification of contradictions resulting from the regional inequality during... In order to reduce the regional differentials or narrow the gap in economic development between eastern and western areas and prevent the intensification of contradictions resulting from the regional inequality during the development process, the government of China launched the Great Campaign of Western Development (GCWD) in 2000. In this paper, we will evaluate the effects of the first 10 years' GCWD and use the latest Chinese annual data from 1978 to 2010 to investigate the problem of regional differentials in the development process, evaluate the effects of GCWD policy and test whether there is a regional Kuznets inverted-U curve in the regional development of China. The result shows that there are both good and bad news: the good news is that the inverted U-shaped curve of absolute differential between eastern and western areas finally emerges (the previous studies showed that the inverted-U curve did not appear and the differentials between eastern and western areas became worse) and the bad news is that the differential is in the first half of the inverted U-shaped curve in our choice of time span (1978-2010), that is, it is still in the situation of deterioration, and the turning better point will emerge in 2025. Although the western areas have benefitted from GCWD, the absolute gap has been still widened. To narrow the gap, the western areas should accelerate the industrial development and the government should adjust the policy and make more efforts to support the development of the industry in the western areas, especially cultivate and support the development of the western characteristic and advantageous industry rather than just supporting the construction of infrastructure in the western areas. 展开更多
关键词 Great Campaign of western Development (GCWD) the gap between eastern and western areas regional inequality or differential inverted-U curve
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Study on the Moment Magnitude of Small and Moderate Earthquakes Located in the Inner Mongolia Region
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作者 Liu Fang Zhang Fan +1 位作者 Li Bin Na Re 《Earthquake Research in China》 CSCD 2018年第1期53-63,共11页
Based on digital seismic waveform data from Inner Mongolia Digital Seismic Network,the source spectrum parameters of 182 small and moderate earthquakes from January,2009to September,2016 are derived,and the seismic mo... Based on digital seismic waveform data from Inner Mongolia Digital Seismic Network,the source spectrum parameters of 182 small and moderate earthquakes from January,2009to September,2016 are derived,and the seismic momentmoment magnitude MW of the earthquakes are calculated.Theand the relationship between stress drop and magnitude are obtained using the linear regression method.It is clear that incorporating the moment magnitude into the seismic quick report catalog and the official earthquake catalog can enrich earthquake observation report content,thus providing better service for earthquake emergency and earthquake scientific research. 展开更多
关键词 The central and western regions of Inner Mongolia SMALL and MODERATE earthquake MOMENT MAGNITUDE Seismic MOMENT
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我国中西部地区经济高质量发展水平测度与区域差异比较
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作者 唐娟莉 高远 《技术与创新管理》 2024年第5期521-531,共11页
了解中西部地区经济高质量发展水平现状,进一步分析各地区经济高质量发展水平存在差异的原因,对加快推动中西部地区经济高质量发展具有重要意义。基于五大新发展理念,构建经济高质量发展水平评价指标体系,采用熵值法,对中西部地区156个... 了解中西部地区经济高质量发展水平现状,进一步分析各地区经济高质量发展水平存在差异的原因,对加快推动中西部地区经济高质量发展具有重要意义。基于五大新发展理念,构建经济高质量发展水平评价指标体系,采用熵值法,对中西部地区156个地级市的经济高质量发展水平进行测度,并通过Dagum基尼系数、耦合协调度模型与Moran’s I指数,探究西部地区经济高质量发展水平的差异性及其原因。研究结果表明:中西部地区整体的经济高质量发展水平呈不断上升趋势,但仍处于较低水平,其中,中部地区的经济高质量发展水平高于西部地区,且两地区之间的发展水平有进一步被拉大的趋势。经济高质量发展水平差距主要来源于区域内差异,且五大新发展理念在互动过程中存在着严重失调的情况,会严重制约经济高质量发展水平的提升。对此,应持续坚持区域协调发展战略,提高地区创新水平,有效推动地区发展之间的良性互动。 展开更多
关键词 经济高质量发展 区域差异性 中西部地区 Dagum基尼系数
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中原地区战国至西汉墓葬出土陶釜研究
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作者 张亮 秦雪松 《文博》 北大核心 2024年第2期72-79,共8页
本文通过系统聚类分析方法,对中原地区战国至西汉墓葬出土的陶釜进行了类型学研究,认为战国中期陶釜以一种特殊葬俗的形式出现在郑州地区,战国晚期开始陶釜迅速发展,分布范围变广,数量和类型明显增多,包含有郑韩文化、晋文化和秦文化三... 本文通过系统聚类分析方法,对中原地区战国至西汉墓葬出土的陶釜进行了类型学研究,认为战国中期陶釜以一种特殊葬俗的形式出现在郑州地区,战国晚期开始陶釜迅速发展,分布范围变广,数量和类型明显增多,包含有郑韩文化、晋文化和秦文化三大系统。进入汉代,陶釜数量急剧减少,类型单一。陶釜在中原地区的发展历程与秦文化有密切的关系。 展开更多
关键词 陶釜 中原地区 战国 西汉 类型学
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鄂西—渝东地区上二叠统大隆组页岩气富集条件与勘探有利区 被引量:1
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作者 李世臻 周志 +10 位作者 李飞 沈斌 徐秋晨 宋腾 张小涛 杨晓光 胡才志 王超 魏思宇 王昱荦 卢妍欣 《天然气工业》 EI CAS CSCD 北大核心 2024年第5期1-15,共15页
近年来,鄂西—渝东地区多口井在二叠系大隆组获得页岩气重要发现和工业气流,展现出新层系海相页岩气良好的勘探开发前景,深化其地质认识对于指导下一步页岩气勘探具有重要意义。为此,基于岩心观察、薄片及扫描电镜观察、测/录井和有机... 近年来,鄂西—渝东地区多口井在二叠系大隆组获得页岩气重要发现和工业气流,展现出新层系海相页岩气良好的勘探开发前景,深化其地质认识对于指导下一步页岩气勘探具有重要意义。为此,基于岩心观察、薄片及扫描电镜观察、测/录井和有机地球化学数据分析,系统研究了该地区页岩沉积特征、储层特征、有机地球化学特征、含气性和保存条件,明确了大隆组海相页岩气勘探有利区。研究结果表明:①晚二叠世大隆期,该区发育深水台盆相沉积,富有机质页岩发育厚度10~60 m,现今埋深具有盆内埋深大、盆外埋深浅的特征;②大隆组自下而上划分为3段,一段以硅质页岩为主,二段岩性较为复杂,三段以混合质页岩为主,测井响应上表现为高自然伽马、高补偿中子、高声波时差、低电阻率、低密度、电阻率向底部逐渐降低的“三高两低一降”特征;③大隆组页岩脆性矿物以石英和方解石为主,平均值分别为40.58%和23.76%,储集空间分为孔隙(有机质孔、矿物颗粒间孔、粒间溶蚀孔、粒内溶蚀孔)和裂缝(矿物层间缝、有机质与矿物间缝、有机质内裂缝)2大类7种类型,以有机质孔为主,孔径分布呈现“四峰”特征,孔体积集中介于1~10 nm和500~5000 nm两个孔径区间;④大隆组有机质丰度高、储层非均质性强、热演化程度高、有机质类型以Ⅱ1型为主、Ⅱ2型为辅,有机质孔发育;⑤大隆组页岩具有较高的含气量,良好的顶底板条件发挥了重要的封闭作用;盆内受构造抬升剥蚀和断裂影响小,保存条件整体较好,盆外残留向斜核部保存条件较好。结论认为:①大隆组是四川盆地页岩气勘探的新领域,在盆地内发育5个勘探有利区,面积合计5500 km^(2),可加快勘探评价节奏;②在盆外发育7个勘探有利区,面积合计6700 km^(2),应优选残留面积大的有利区开展风险勘探,寻找新的突破和发现。 展开更多
关键词 海相 页岩气 新领域 鄂西—渝东地区 上二叠统 大隆组 富集地质条件 勘探有利区
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“一带一路”建设中中西部地区对外开放战略思考点
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作者 张玉杰 《广西经济》 2024年第1期7-14,共8页
“内陆地区外向化、中西部地区国际化”是促进区域协调发展的重点,是践行“一带一路”建设的重要内容,也是边疆地区实现跨越式发展的必然选择。影响西部地区发展的主要问题是“要素贫困”和“流动性资源短缺”,解决这些问题的根本方略... “内陆地区外向化、中西部地区国际化”是促进区域协调发展的重点,是践行“一带一路”建设的重要内容,也是边疆地区实现跨越式发展的必然选择。影响西部地区发展的主要问题是“要素贫困”和“流动性资源短缺”,解决这些问题的根本方略就是运用习近平新时代中国特色社会主义思想构建和实施对外开放新战略,运用对空开放、沿边开放、沿路开放、网络开放等全方位开放方式,促进区域融合,融入国内和国际两个大循环之中,将当地丰富的自然资源转化为经济资源,转化为生产要素,汇聚流动性资源,推动财富增长,促进区域整体发展,建设中国式现代化。 展开更多
关键词 “一带一路”建设 对外开放 中西部地区发展战略 沿边开放 中国国际化
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川西藏东地区隧道围岩有害气体孕育机制及逸出风险评价研究 被引量:1
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作者 张吉禄 刘新荣 +5 位作者 周小涵 祁占锋 刘瀚之 刘煜宇 孙浩 吴涛 《隧道建设(中英文)》 CSCD 北大核心 2024年第2期296-307,共12页
青藏高原复杂的地质构造使区域内断裂分布密集、岩性变化巨大,现有的研究成果无法有效预测岩层内有害气体赋存种类与状态。基于川西藏东地质演化相关研究成果,对区域内岩石、断裂构造以及水热循环影响下有害气体的成因及组分特征进行研... 青藏高原复杂的地质构造使区域内断裂分布密集、岩性变化巨大,现有的研究成果无法有效预测岩层内有害气体赋存种类与状态。基于川西藏东地质演化相关研究成果,对区域内岩石、断裂构造以及水热循环影响下有害气体的成因及组分特征进行研究。通过对区域内地层构造及岩石分布进行分析,明确区域内主要气藏类型及分布范围;建立复杂地层有害气体逸出风险评价体系,并通过现场监测对评价效果进行验证。结果表明:1)川西藏东地区岩层主要有害气体孕育类型包括岩浆岩脱气孕育气体、变质岩化学反应释放气体、沉积岩油气矿藏富集气体、金属矿伴生气体等;其中,岩浆岩孕育有害气体主要赋存于入侵通道形成的气囊内,变质岩孕育有害气体主要赋存于酸性岩浆岩与碳酸岩接触面以及金属矿附近,沉积岩孕育有害气体主要赋存于油气盖层内。2)岩石圈断裂对深部有害气体的赋存最有利,水热循环通过物质扩散和水力运移2种方式加速深部有害气体的运移,其中深大主断裂控制型水热循环模式影响最显著。3)基于川西藏东地区地层岩性及断裂构造特征,对CO_(2)、CH_(4)、SO_(2)及H_(2)S等主要有害气体的赋存区域进行划分。4)根据研究区域地层岩性、断裂构造、水热分布特点,建立复杂地层有害气体逸出风险评价体系;根据隧道开挖高浓度有害气体逸出可能性划分为5个风险等级,并针对不同逸出风险提出相应防治建议。 展开更多
关键词 川西藏东地区 有害气体 隧道围岩 断裂构造 评价体系 赋存机制
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2018-2021年我国东中西部地区医防协同耦合协调度分析
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作者 徐海玉 曹桑蔚 +5 位作者 李诗麒 严豪 满晓玮 蒋艳 赵丽颖 程薇 《卫生软科学》 2024年第9期50-54,共5页
[目的]探究我国东中西部地区医防协同耦合协调度水平,为我国医防协同发展提供参考。[方法]基于文献研究法构建评价指标体系,运用熵权法和耦合协调度模型测算医防协同耦合协调度水平。[结果]2018-2021年我国东中西部地区平均耦合协调度... [目的]探究我国东中西部地区医防协同耦合协调度水平,为我国医防协同发展提供参考。[方法]基于文献研究法构建评价指标体系,运用熵权法和耦合协调度模型测算医防协同耦合协调度水平。[结果]2018-2021年我国东中西部地区平均耦合协调度分别为0.527、0.531、0.470,耦合协调度水平整体偏低。[结论]2018-2021年我国东中西部地区医防协同机制不完善,重医轻防现象严重,两系统发展不协调现象日益加剧,提示应提升预防在健康中国战略中的地位,逐渐改善“重医疗、轻预防”的局面,构建医疗与公共卫生有效协同机制。 展开更多
关键词 医防协同 耦合协调度 东部地区 中部地区 西部地区 指标体系 熵权法
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基于自然伽马测井的煤系关键金属精细勘探技术
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作者 边晓 王雷 +6 位作者 王喜军 杨敏芳 叶攀 祖淯文 索金玲 邵龙义 鲁静 《地质学报》 EI CAS CSCD 北大核心 2024年第8期2531-2540,共10页
滇东—黔西上二叠统煤系底部赋存着累积厚度达数米、以自然伽马测井正异常为特征的Nb-Zr-REY-Ga型关键金属矿层,是我国最有开发潜力的煤系关键金属资源之一。当前对该矿层的研究主要聚焦于关键金属物质来源、赋存状态和成矿模式等方面,... 滇东—黔西上二叠统煤系底部赋存着累积厚度达数米、以自然伽马测井正异常为特征的Nb-Zr-REY-Ga型关键金属矿层,是我国最有开发潜力的煤系关键金属资源之一。当前对该矿层的研究主要聚焦于关键金属物质来源、赋存状态和成矿模式等方面,而利用自然伽马测井数据对该矿层进行定量识别和浓度计算等工作还未开展过,尽管这项工作对将来这些矿层关键金属的勘探和开发具有重要意义。论文以Zr和Ga两种元素为例,利用收集和实测的关键金属浓度及其对应的自然伽马值等数据,进行了基于自然伽马测井的关键金属矿层精细勘探技术研究。结果表明:研究区Zr和Ga元素浓度的预测模型分别为y=133.42x^(2)+262.23x+224.43和y=31.587e^(0.2273x),指示两者最低开发利用浓度(2000μg/g和50μg/g)对应的自然伽马值分别为2.8 pA/kg和2.0 pA/kg。发现Haar小波3层分解获得的预测矿层位置与地球化学实测的矿层位置吻合度最高。预测模型验证结果表明,Zr和Ga元素浓度预测平均相对误差分别为14.21%和10.97%,矿层厚度预测平均相对误差分别为4.16%和4.82%,说明论文建立的关键金属精细勘探技术可以精确识别研究区关键金属矿层浓度和厚度,对滇东—黔西地区Nb-Zr-REY-Ga型关键金属矿层的精细勘探具有较好的应用价值。 展开更多
关键词 滇东—黔西地区 煤系关键金属 上二叠统煤系 自然伽马测井 小波变换
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中国-中东欧国家合作机制2012—2022年区域国别研究回顾与建议
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作者 王春岩 尚宇红 《北京第二外国语学院学报》 北大核心 2024年第3期118-131,共14页
中国-中东欧国家合作机制自2012年建立以来,至2022年已走过10年的发展历程。本文旨在回顾和分析这一时期中国学者围绕中东欧国家所进行的研究,以期为未来的研究提供参考和借鉴。本文采用文献综述法,系统梳理了2012—2022年我国中东欧研... 中国-中东欧国家合作机制自2012年建立以来,至2022年已走过10年的发展历程。本文旨在回顾和分析这一时期中国学者围绕中东欧国家所进行的研究,以期为未来的研究提供参考和借鉴。本文采用文献综述法,系统梳理了2012—2022年我国中东欧研究机构与学者、研究成果的产出及学科分布特征等情况。研究发现,中东欧国别与区域研究在数量和质量上均有显著提升,但仍存在一些问题,如通晓该地区的专门人才缺乏,研究方法单一,学科交叉不足等。本研究为中国-中东欧合作提供战略层面的参考,也为中东欧国别区域视域下的学术发展提供参考。 展开更多
关键词 中国-中东欧国家合作机制 中东欧 区域国别研究 跨学科研究
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中西部高等教育振兴计划的政策效应评估 被引量:2
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作者 马浚锋 《湖南师范大学教育科学学报》 CSSCI 北大核心 2024年第1期84-96,共13页
“中西部高等教育振兴计划”等政策旨在解决制约中西部高等教育发展的突出问题,然而,目前多数相关研究仍然集中于政策文本的质性分析。研究采用双重差分法(DID)构建计量模型评估了“中西部高等教育振兴计划”的政策效应。研究发现:其一... “中西部高等教育振兴计划”等政策旨在解决制约中西部高等教育发展的突出问题,然而,目前多数相关研究仍然集中于政策文本的质性分析。研究采用双重差分法(DID)构建计量模型评估了“中西部高等教育振兴计划”的政策效应。研究发现:其一,入选“中西部高校基础能力建设工程”的省属地方高校的科研课题立项数提高了13.40%,科研成果产出提高了14.80%,科研成果获奖提高了28%。其二,随着“中西部省域高水平大学建设”政策的相继实施,中西部省域高等教育的专利授权转让数提高了22.1%,并通过科研成果转化参与到区域社会经济发展中;中西部省域高职称教师规模增量获得了5.50%的纯政策效应,充实了师资队伍的骨干力量,但青年教师却没有得到有效补充。展望未来,中西部高等教育振兴的重心应放在政策的可持续性和省域自足能力的培育上,并为青年教师的成长提供空间。 展开更多
关键词 中西部省域 区域高等教育 政策效应 政策评估 双重差分法
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