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A Study of Impacts on China Post after China Joins the World Trade Organization 被引量:1
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作者 ZHAO Shuan-liang, WU Hong-bin, MENG Yan-fen (Shijiazhauang Postal College, Shijiazhuang 050021, P.R.China) 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2001年第3期65-68,76,共5页
China's about to join World Trade Organization (WTO) which means the Chinese post markets will be gradually open to the world, which will certainly have great impacts on its many industries and enterprises. As one... China's about to join World Trade Organization (WTO) which means the Chinese post markets will be gradually open to the world, which will certainly have great impacts on its many industries and enterprises. As one of the state enterprises, China post will certainly be affected on many traditional and new postal services that it provides. In this paper we discuss the impacts on the three aspects: China post reform, postal market and postal management. 展开更多
关键词 china post WTO GATS
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Current Situations and Developing Tendency of China Post's Logistic Technology
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作者 XURu-wei LIXue-ping 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2004年第1期106-110,114,共6页
This paper briefly introduces the construction of China Post's physical network and information network and offers some general ideas about how to develop modern postal logistics. It dwells on the sortation techno... This paper briefly introduces the construction of China Post's physical network and information network and offers some general ideas about how to develop modern postal logistics. It dwells on the sortation technology, the Chinese Character Recognition Technology and the current situations and tendencies of the Research and Development (R&D) of the Logistic Information Management System. 展开更多
关键词 logistic technology current situations china post
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China Post,Inc.
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作者 LAN XINZHEN 《Beijing Review》 2006年第41期32-33,共2页
关键词 china post Inc
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Petrogenesis of the Late Triassic shoshonitic Shadegai pluton from the northern North China Craton: Implications for crust-mantle interaction and post-collisional extension 被引量:3
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作者 Liqiong Jia Liang Wang +2 位作者 Genhou Wang Shibin Lei Xuan Wu 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第2期595-610,共16页
Latest Permian to Triassic plutons are widespread in the northern North China Craton(NCC); most of them show calc-alkaline, high-K calc-alkaline, or alkaline geochemical features. The Shadegai pluton in the Wulashan a... Latest Permian to Triassic plutons are widespread in the northern North China Craton(NCC); most of them show calc-alkaline, high-K calc-alkaline, or alkaline geochemical features. The Shadegai pluton in the Wulashan area has shoshonitic affinity and I-type character, and is composed of syenogranites containing abundant mafic microgranular enclaves(MMEs). LA-MC-ICP-MS U-Pb data yield weighted mean 206 Pb/238 U ages of 222 ± 1 Ma and 221 ± 1 Ma for the syenogranites and MMEs, respectively, suggesting their coeval formation during the Late Triassic. The syenogranites have high SiO_2(70.42-72.30 wt%),K_2O(4.58-5.22 wt.%) and Na_2O(4.19-4.43 wt.%) contents but lower concentrations of P_2O_5(0.073-0.096 wt.%) and TiO_2(0.27-0.37 wt.%), and are categorized as I-type granites, rather than A-type granites, as previously thought. These syenogranites exhibit lower(^(87)Sr/^(86)Sr)i ratios(0.70532-0.70547) and strongly negative whole-rock εNd(t) values(-12.54 to-11.86) and zircon εHf(t) values(-17.81 to-10.77),as well as old Nd(1962-2017 Ma) and Hf(2023-2092 Ma) model ages, indicating that they were derived from the lower crust.Field and petrological observations reveal that the MMEs within the pluton probably represent magmatic globules commingled with their host magmas. Geochemically, these MMEs have low SiO_2(53.46-55.91 wt.%)but high FeOt(7.27-8.79 wt.%) contents. They are enriched in light rare earth elements(LREEs) and large ion lithophile elements(LILEs), and are depleted in heavy rare earth elements(HREEs) and high field strength elements(HFSEs). They have whole-rock(^(87)Sr/^(86)Sr)i ratios varying from 0.70551 to 0.70564, εNd(t) values of -10.63 to -9.82, and zircon εHf(t) values of -9.89 to 0.19. Their geochemical and isotopic features indicate that they were derived from the subcontinental lithospheric mantle mainly metasomatized by slab-derived fluids, with minor involvement of melts generated from the ascending asthenospheric mantle. Petrology integrated with elemental and isotopic geochemistry suggest that the Shadegai pluton was produced by crust-mantle interactions, i.e., partial melting of the lower continental crust induced by underplating of mantle-derived mafic magmas(including the subcontinental lithospheric mantle and asthenospheric mantle), and subsequent mixing of the mantle-and crust-derived magmas. In combination with existing geological data, it is inferred that the Shadegai pluton formed in a post-collisional extensional regime related to lithospheric delamination following the collision between the NCC and Mongolia arc terranes. 展开更多
关键词 Magma mixing CRUST-MANTLE interaction LITHOSPHERIC delamination post-COLLISION North china CRATON
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Land suitability assessment for post-earthquake reconstruction: A case study of Lushan in Sichuan, China 被引量:2
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作者 汤青 李扬 徐勇 《Journal of Geographical Sciences》 SCIE CSCD 2015年第7期865-878,共14页
Land suitability assessment (LSA) is one of the key processes of land-use planning. Given its particularity of land suitability assessment for post-earthquake reconstruction, this paper takes into account geological... Land suitability assessment (LSA) is one of the key processes of land-use planning. Given its particularity of land suitability assessment for post-earthquake reconstruction, this paper takes into account geological conditions, risk of disasters, water and land resources conditions, and eco-environmental suitability and emphasizes safety factor in the assessment. Taking the April 20, 2013 Mw 6.6 Lushan earthquake as a case, this assessment establishes factors system, uses GIS spatial analysis techniques and data of geology, topography, resources, and eco-environment to evaluate the land suitability for reconstruction. The results show that: (1) the spatial characteristics of land suitability for reconstruction at grid scale and administrative scale manifest that most of the piedmont plains in the east are suitable for large-scale population aggregation, industrialization, and urbanization development; and (2) for the six hard-hit counties, Mingshan is the preferred region for large-scale post-earthquake reconstruction due to its high construction index and suitable land per capita, and some plots of land in the valleys could be selected for in-situ small-scale reconstruction in Lushan. The land suitability assessment for post-earthquake reconstruction would be significant to making sound reconstruction planning for achieving sustainable regional development in the Mw 6.6 Lushan earthquake stricken area. This study could be used as a reference for the regions with similar events. 展开更多
关键词 land suitability post-earthquake reconstruction GIS Lushan china
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China's Post and Telecommunications Service
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作者 Wang Hualong 《China's Foreign Trade》 1995年第5期21-22,共2页
In 1994, the handling capacity and business volume of China’s posts and telecommunications fulfilled the target of the Eighth Five-Year Plan (1991-1995) a year ahead of schedule and that of quadrupling the business v... In 1994, the handling capacity and business volume of China’s posts and telecommunications fulfilled the target of the Eighth Five-Year Plan (1991-1995) a year ahead of schedule and that of quadrupling the business volume during the period of 1980-2000 six years in advance. 1. The comprehensive communications capacity further enhanced with the construction of the telecommunication mains transmission network mainly composed of optical fibre cables is now in place. Seven 展开更多
关键词 length china’s post and Telecommunications Service MORE THAN
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DEVELOPMENT OF CHINA'S POST AND TELECOMMUNI-CATIONS
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作者 Wang Hualong 《China's Foreign Trade》 1997年第9期14-15,共2页
In handling patent disputes, China observes an operational method of mutual cooperation and coordination through two channels: judicial adjudication and administrative settlement. Over the past decade, practice has pr... In handling patent disputes, China observes an operational method of mutual cooperation and coordination through two channels: judicial adjudication and administrative settlement. Over the past decade, practice has proved that the specific way of handling patent disputes by patent administrative organs has played an important role in the prompt resolu tion of patent disputes, protecting the legitimate rights and interests of patent- 展开更多
关键词 OVER DEVELOPMENT OF china’S post AND TELECOMMUNI-CATIONS THAN
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A Historic Leap for China's Post and Telecommmunications
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作者 Wang Hualong 《China's Foreign Trade》 1996年第5期21-22,共2页
China’s post and telecomsector achieved furthergiant development in 1995,afterit accomplished its eighth five-year plan a year ahead ofschedule,and realized its targetof eight-fold expansion duringthe period of 1980-... China’s post and telecomsector achieved furthergiant development in 1995,afterit accomplished its eighth five-year plan a year ahead ofschedule,and realized its targetof eight-fold expansion duringthe period of 1980-2000 sixyears ahead of schedule,thusresulting in a historic leap. 展开更多
关键词 A Historic Leap for china’s post and Telecommmunications
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Post-Neogene Structural Evolution: An Important Geological Stage in the Formation of Gas Reservoirs in China
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作者 WANGTingbin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期651-661,共11页
Tectonic movements since the Neogene have been the major developmental and evolutional stages of the latest global crustal deformation and orogenic movements. China is located in a triangular area bounded by the India... Tectonic movements since the Neogene have been the major developmental and evolutional stages of the latest global crustal deformation and orogenic movements. China is located in a triangular area bounded by the Indian landmass, the West Siberian landmass and the Pacific Plate, characterized by relatively active tectonic movements since the Neogene, and in this region, natural gas would have been very easy to dissipate, or difficult to preserve. Therefore, the characteristics of post-Neogene tectonic movements offer important geological factors in researching the formation and preservation of gas reservoirs in China. Summarizing the reservoiring history of gas fields in China, although there are some differences between various basins, they are all affected by the tectonic movements since the Neogene. These movements have certainly caused destruction to the reservoiring and distribution of natural gas in China, which has resulted in a certain dissipation of natural gas in some basins. As a whole, however, they have mainly promoted the reservoiring and accumulation of natural gas: (1) a series of China-type foreland basins have been formed between basins and ridges in western China, which provide favorable conditions for the formation of large and medium gas fields, as well as controlling the finalization of gas reservoirs in the basins; (2) rows and belts of anticlines have been formed in the Sichuan Basin in central China, which have been the major stages of the formation and finalization of gas reservoirs in that basin; the integral and quick rising and lifting, and a further west-dipping in the Ordos Basin have resulted in a further accumulation of natural gas in gas fields from Jingbian to Uxin; (3) in eastern China, the Bohai movement in the late Pliocene has provided favorable geological conditions for lately-formed gas reservoirs in the Bohai Sea area mainly composed of the Bozhong depression; and it also resulted in secondary hydrocarbon generation and formation of secondary gas reservoirs in other basins, as well as the formation of many carbon dioxide gas fields of inorganic origin; (4) in the offshore area, it promoted not only the formation of gas reservoirs of organic origin, but also the formation of inorganic origin non-hydrocarbon gas reservoirs, as well as the organic and inorganic natural gas of mixed origin, which resulted in the relatively complicated characteristics of gas reservoirs in the area. In short, tectonic movements activated since the Neogene resulted in a reservoiring model mainly characterized by late and superlate hydrocarbon generation and accumulation. These events provide an important geological stage that should not be neglected when studying the formation of gas reservoirs in China. 展开更多
关键词 post-Neogene tectonic movement natural gas in china late stage superlate stage final reservoir stage
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ROLE OF POST-OROGENICEXTENSIONAL TECTONICS IN THE SUPERGIANT ANTIMONY MINERALIZATION IN CENTRAL HUNAN PROVINCE, SOUTH CHINA
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作者 Yi Jianbin Shan Yehua (Changsha Institute of Geotectonics,Academia Sinica, Changsha, 410013, China) 《Geotectonica et Metallogenia》 1995年第Z1期62-70,共9页
The Xikuangshan antimony deposit in central Hunan, South China, is the largest antimony deposit ever known in the world. The ore bodies are strictly confined to the footwalls of mafor high-angle normal faults which tr... The Xikuangshan antimony deposit in central Hunan, South China, is the largest antimony deposit ever known in the world. The ore bodies are strictly confined to the footwalls of mafor high-angle normal faults which transect the inclined folds in the flank;away from the fault planes,both the homogenization temperatures of inclusions in gangue minerals and the intensity of antimony mineralization decrease.These characteristics strongly demonstrate that the faults are used as the conduit for the metal-bearing fluid in mineralization.The normal faults,striking the NE to NNE,are interpreted to be generated by the postmgenic extension in the time from Cretaceous to Paleogene.Crustal or lithospheric thinning, directly resulting from regional extension inevitably increase the geothermal gradient, Which is likely to cause large-scale convection of underground water that may leach out and transport valuablemetals such as Sb from source rocks.Focussed discharge along the fault zones contributes to the formation of the supergiant antimony deposit in Xikuangshan under the appropriate sedimentary barrier. 展开更多
关键词 post-OROGENIC extension supergiant ANTIMONY MINERALIZATION central HUNAN SOUTH china
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民国时期“晨报系”的迁流考察(1916-1937)
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作者 郑思源 付登舟 《深圳社会科学》 2026年第1期130-139,共10页
“晨报系”主要由《晨钟报》(1916-1918)、《晨报》(1918-1928)、《新晨报》(1928-1930)及《北平晨报》(1930-1937)构成,是民国时期北京报界发行年限最长、权势博弈最剧烈、立场变化最频繁的报系。“晨报系”报刊的三次更名活动,既是政... “晨报系”主要由《晨钟报》(1916-1918)、《晨报》(1918-1928)、《新晨报》(1928-1930)及《北平晨报》(1930-1937)构成,是民国时期北京报界发行年限最长、权势博弈最剧烈、立场变化最频繁的报系。“晨报系”报刊的三次更名活动,既是政治博弈背景下舆论资源被攘夺的直接后果,又是“晨报系”报人群体在老成员退出和新成员加入的过程中维持“晨报系”的生存与发展的必然结果。回顾“晨报系”二十年发行史,“晨报系”报人群体屡次受到各方政治力量的监视、审查与查封,却又屡次在权势更迭的夹缝中涅槃重生。他们在各方政治势力的裹挟态势下不断调整编辑策略,最大限度地争取编辑报道的自主公正,却形成了这样一个悖论:在权势更迭的背景下,“晨报系”越与“政治”保持距离,就越无可避免被卷入政治旋涡;越避免军阀的染指,就越容易遭受各派政治势力的攘夺。在新闻自由的职业理想中,“晨报系”越强调编辑报道的客观公正,就越无法独立自主决定内容策划。这不仅反映了“晨报系”报人群体在权力规训和职业理想之间的抗争与权变,也为研究近代中国社会的权势更迭与思潮演变提供了珍贵的历史样本。总之,“晨报系”的迁流历程,勾勒了近代中国报人群体在接受权力规训与争取新闻自由的夹缝中艰难腾挪的历史图景。 展开更多
关键词 民国时期 晨报系 报人群体 新闻与传播
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Spatial Pattern and Influencing Factor Analysis of Attended Collection and Delivery Points in Changsha City, China 被引量:5
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作者 XUE Shuyan LI Gang +3 位作者 YANG Lan LIU Ling NIE Qifan Muhammad Sajid MEHMOOD 《Chinese Geographical Science》 SCIE CSCD 2019年第6期1078-1094,共17页
Attended collection and delivery points are vital components of ‘last-mile logistics’.Based on point of interest(POI) data for Cainiao Stations and China Post stations in Changsha City, China, this paper provides a ... Attended collection and delivery points are vital components of ‘last-mile logistics’.Based on point of interest(POI) data for Cainiao Stations and China Post stations in Changsha City, China, this paper provides a detailed exploration of the basic features, spatial distribution, and location influencing factors of attended collection and delivery points.Specifically, analyses of the types, service objects and location distributions of the attended collection and delivery points alongside a discussion of their spatial pattern and influencing factors provides a reference for their general geographic layout and characteristics.The findings of this study indicate that: 1) The main mode of operation of attended collection and delivery points is franchises, with other modes of operation rely on supermarkets and other individual shop types.2) The main service targets of attended collection and delivery points are communities, schools, and businesses, followed by townships, enterprises, scenic spots, and administrative units.3) Approximately 77.44% of the attended collection and delivery points are located near the exits of service areas;others are situated in the centre of the service areas.For the Cainiao Stations, 80% are located within 125 m of the exit;for the China Post stations, 80% are located within 175 m of the exit.4) The spatial distribution of the attended collection and delivery points in Changsha is unbalanced, with ‘more centre and fewer surrounding’.The centre is an ‘inverted triangle’, and the edge is an ‘orphan’, showing a northwest-southeast orientation and symmetrical along the axis.The layout of the attended collection and delivery points forms three core areas, and the number of sites decreases with the distance from the core.5) The number and distribution of the attended collection and delivery points are strongly consistent with the regional economic development level, population, and roadway system traffic convenience.Most attended collection and delivery points are on residential, scientific and educational, and commercial and financial land. 展开更多
关键词 attended COLLECTION and delivery POINTS Cainiao STATIONS china post STATIONS spatial PATTERN influencing FACTORS Changsha china
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Study on the Post-evaluation of Environmental Planning Based on Logical Framework Approach 被引量:2
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作者 CHEN Yu-xian DONG Ze-qin 《Meteorological and Environmental Research》 CAS 2011年第2期1-5,9,共6页
[Objective] The aim was to conduct post-evaluation on environmental planning by means of logical framework approach. [Method] Taking environmental planning during '11th Five-year Plan' in a certain province fo... [Objective] The aim was to conduct post-evaluation on environmental planning by means of logical framework approach. [Method] Taking environmental planning during '11th Five-year Plan' in a certain province for example, by means of logical framework approach (LFA), the post-evaluation on environmental planning was carried out from the aspects of evaluation content, index system, implementation steps, evaluation feedback and input-output analysis of environmental planning. [Result] The post-evaluation on environmental planning by means of LFA achieved expected purpose and various indexes at different stages of environmental planning was assessed, and then corresponding countermeasures were put forward according to the problems which were found by problem tree of environmental planning project. [Conclusion] The study could provide theoretical references for the post-evaluation on environmental planning in future. 展开更多
关键词 Logical framework approach Environmental planning during '11th Five-year Plan' post-EVALUATION china
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Metallogenic Series Related to Permian Mafic Complex in North Xinjiang:Post-collisional Stage or Mantle Plume Result? 被引量:7
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作者 WANG Yuwang WANG Jingbin +1 位作者 WANG Lijuan LONG Lingli 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第4期788-795,共8页
There are four deposit types related to a Permian mafic complex in northern Xinjiang, i.e., copper-nickel sulfide deposit, vanadic titanomagnetite deposit, magnetite (-cobalt) deposit and Cu-Ni- VTiFe composite depo... There are four deposit types related to a Permian mafic complex in northern Xinjiang, i.e., copper-nickel sulfide deposit, vanadic titanomagnetite deposit, magnetite (-cobalt) deposit and Cu-Ni- VTiFe composite deposit. The deposits are distributed spanning tectonic units with close and consecutive metallogenic ages. A transitional deposit type can occur among the end-member deposits. Trace elements of host rocks show that they can derive from similar source area. Hence, they constitute a particular metallogenic series related to a mafic-ultramafic complex that is also a symbol series of the post-collisional stage of the Central Asia Metallogenic Province (CAMP). The metallogenic ages of the series are between 260 Ma and 300 Ma throughout the Permian. Unlike mineralization from a mantle plume, the metallogenic period of this series spans at least 40 Ma. Compared with related deposits of the Emeishan mantle plume, the North Xinjiang series has a similar ore-forming element assemblage but has preferably developed Cu-Ni sulfide deposits rather than vanadic titanomagnetite deposits. In concomitance with this series, North Xinjiang area has developed a set of syntectonic Au-Cu-Mo metallogenic series related to a felsic volcanic-intrusive complex, which might indicate that there is no direct relationship with mantle plume activity. From early to late, i.e., the sequence of copper-nickel sulfide to magnetite (-cobalt) to vanadic titanomagnetite deposit, the host rock series evolves from mafic-ultramafic and tholeiite series to mafic and alkalic series, the ~REE content tends to increase with increasing of REE fractionation, and some of the trace elements (particularly LIL) also show an increasing tendency. The above evolutionary regularity possibly reflects a course where the magma source deepens and thermal interface moves down, energy gradually exhausts, and neo-continental crust forming in the postcollision stage tends to stabilize. 展开更多
关键词 metallogenic series mafic complex mantle-derived magma post-COLLISION PERMIAN North Xinjiang china
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Genesis of Highly Fractionated I-Type Granites from Fengshun Complex:Implications to Tectonic Evolutions of South China 被引量:17
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作者 Zuomin Zhou Changqian Ma +3 位作者 Caifu Xie Lianxun Wang Yuanyuan Liu Wei Liu 《Journal of Earth Science》 SCIE CAS CSCD 2016年第3期444-460,共17页
The South China Block is characterized by the large-scale emplacement of felsic magmas and giant ore deposits during the Yanshanian. We present zircon Hf isotopic compositions, whole-rock major and trace element compo... The South China Block is characterized by the large-scale emplacement of felsic magmas and giant ore deposits during the Yanshanian. We present zircon Hf isotopic compositions, whole-rock major and trace element compositions of the Fengshun complex, located in eastern Guangdong Province, South China. The Fengshun complex is a multi-stage magmatic intrusion. It is composed of two main units, i.e., the Mantoushan(MTS) syeno-monzogranites, alkali feldspar granites and the Hulutian(HLT) alkali feldspar granites. LA-ICPMS zircon dating shows that the complex emplaced in 166–161 and 139±2 Ma, respectively. Geochemically, the MTS granites show relatively various geochemical compositions with low REE contents(87.76×10-6–249.71×10-6), Rb/Sr ratios(1.19–58.93), pronounced Eu negative anomaly(0.01–0.37) and low Nb/Ta ratios(2.40–6.82). In contrast, the HLT granites exhibit relatively stable geochemical characteristics with high REE contents(147.35×10-6– 282.17×10-6), Rb/Sr ratios(2.05–10.30) and relatively high Nb/Ta ratios(4.45–13.00). The isotopic data of the MTS granites display relatively enriched values, with ISr varying from 0.708 2 to 0.709 7, εNd(t) from-7.8 to-6.9 and εHf(t) from-7.4 to-3.2, in comparison with those of the HLT which are ISr=0.703 05–0.704 77, εNd(t)=-5–-3.4 and εHf(t)=-0.7–1.8). The two-stage model ages of the MTS granites(T2DM(Nd)=1.51–1.59 Ga and T2DM(Hf)=1.26–1.48 Ga) are also higher than those of the HLT granites(T2DM(Nd)=1.21–1.34 Ga and T2DM(Hf)=0.96–1.10 Ga). Thus the MTS and HLT granites might originate from different sources. The former is more likely derived from partial melting of Meso-Proterozoic basement triggered by upwelling of asthenosphere and/or underplate of the basaltic magma and then extensive fractional crystallisation, similar to the genesis of Early Yanshanian granitoids of the EW-trending tectono-magmatism belt in the Nanling range. In comparison, the latter might have involved with asthenosphere component, similar to the Early Cretaceous granitoids of NE-NNE-trending granitoid-volcanic belt in coastal region, southeastern China. We propose that the MTS granites were mainly formed in Paleo-Tethyan post-orogenic extensional tectonic setting whereas the HLT granites were formed in the back-arc extensional tectonic setting. The period at 139 Ma represents the initial time of roll-back of the paleo-Pacific Plate in SE-trending. 展开更多
关键词 Sr-Nd-Hf isotopes Late Mesozoic magmagtism highly fractionated I-type granite post-orogeny roll-back South china
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Devonian alkaline magmatism in the northern North China Craton:Geochemistry,SHRIMP zircon U-Pb geochronology and Sr-Nd-Hf isotopes 被引量:6
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作者 Dingling Huang Qingye Hou 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第1期171-181,共11页
The Wulanhada pluton is among the rare suite of Devonian alkaline plutons occurring along the northern margin of the North China Craton(NCC).The intrusion is mainly composed of quartz-monzonite.Here we report zircon... The Wulanhada pluton is among the rare suite of Devonian alkaline plutons occurring along the northern margin of the North China Craton(NCC).The intrusion is mainly composed of quartz-monzonite.Here we report zircon SHRIMP U-Pb data from this intrusion which shows emplacement age of ca.381.5 Ma.The rock is metaluminous with high(Na2O + K2O) values ranging from 8.46 to 9.66 wt.%.The REE patterns of the rocks do not show any Eu anomaly whereas the primitive-mantle-normalized spider diagram shows strong positive Sr and Ba anomalies.The Wulanhada rocks exhibit high initial values of(87Sr/86Sr)t = 0.70762-0.70809,low εNd(t) =-12.76 to-12.15 values and negative values of εHf(t) =-23.49 to-17.02 with small variations in(176Hf/177Hf),(0.281873-0.282049).These geochemical features and quantitative isotopic modeling results suggest that the rocks might have been formed through the partial melting of Neoarchean basic rocks in the lower crust of the NCC.The Wulanhada rocks,together with the Devonian alkaline rocks and mafic-ultramafic complex from neighboring regions,constitute a post-collisional magmatic belt along the northern NCC. 展开更多
关键词 North china Craton SHRIMP zircon geochronology Sr-Nd-Pb-Hf isotopes post-collisional magmatic belt Tectonics
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作为中国抗战大使的胡适形象——以《纽约时报》《华盛顿邮报》的报道为文本的讨论
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作者 欧阳哲生 安泰和 《安徽史学》 北大核心 2025年第4期136-151,共16页
1938年9月至1942年9月胡适担任中国驻美国大使。如何评价胡适担任这一要职的工作成绩,学界历来存有争议。在此期间,美国主流媒体《纽约时报》《华盛顿邮报》围绕胡适发表的抗战言论及其活动亦作了大量报道,从这些报道,人们可以窥察当时... 1938年9月至1942年9月胡适担任中国驻美国大使。如何评价胡适担任这一要职的工作成绩,学界历来存有争议。在此期间,美国主流媒体《纽约时报》《华盛顿邮报》围绕胡适发表的抗战言论及其活动亦作了大量报道,从这些报道,人们可以窥察当时美国新闻媒体对胡适工作表现的感受和印象。《华盛顿邮报》较多地追踪胡适在华埠社交圈的各种外交活动和社会交际,《纽约时报》则对胡适持守的抗日立场和各种动态作了正面宣传推介。两报对胡适的工作成就和为人表现给予了高度赞赏,罕见地称其是中国近代以来最好的外交官。 展开更多
关键词 胡适 抗日战争 中国大使 《纽约时报》 《华盛顿邮报》
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华南武夷-云开造山带早志留世喷流沉积成矿作用:以超大型吴川-四会-韶关黄铁矿带为例
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作者 张迎迎 罗泰义 +3 位作者 甘甜 周明忠 韩心巧 郑胡艺 《矿物学报》 北大核心 2025年第3期624-643,共20页
华南武夷–云开造山带西缘的吴川–四会–韶关(WSS)喷流沉积型黄铁矿成矿带探明资源量约3.7亿t,但其主要矿床(大降坪、西牛-红岩、大宝山)的成矿时代存在显著差异,且缺乏与区内广泛发育的加里东期花岗岩匹配的同期喷流沉积矿床。为揭示... 华南武夷–云开造山带西缘的吴川–四会–韶关(WSS)喷流沉积型黄铁矿成矿带探明资源量约3.7亿t,但其主要矿床(大降坪、西牛-红岩、大宝山)的成矿时代存在显著差异,且缺乏与区内广泛发育的加里东期花岗岩匹配的同期喷流沉积矿床。为揭示加里东期后碰撞伸展背景下喷流沉积成矿作用,本研究对WSS带北段大宝山矿床赋矿地层顶部蚀变碱性玄武岩和中段西牛矿床硅化黄铁矿化板岩进行了LA-ICP-MS锆石U–Pb定年,并对研究区相关火成岩年龄进行了梳理。通过对大宝山碱性玄武岩的锆石定年研究,厘定了大宝山地区早志留世火山活动的演化时序(早期英安岩(434.96±0.31)Ma,中期安山岩(433.99±0.75)Ma,晚期碱性玄武岩(430.8±1.3)Ma)。西牛矿床中矿化板岩的原岩为火山灰层,其锆石U–Pb谐和年龄为(432.9±0.6)Ma,首次将该矿床限定为早志留世成矿。综合大降坪矿床的钾质斑脱岩年龄((432.5±1.3)Ma),本研究首次确证沿吴川–四会断裂带展布的大降坪、西牛、大宝山等喷流沉积矿床共同构成了早志留世(兰多维列统-温洛克统)吴川−四会−韶关黄铁矿带。该成矿带是华南加里东期碰撞后伸展阶段(ca.440~400 Ma),由吴川–四会深大断裂诱发的火山作用与古海洋热液活动的地质响应;未来勘探应关注该深大断裂两侧的次级断裂和火山盆地。 展开更多
关键词 锆石U–Pb定年 吴川–四会–韶关早志留世黄铁矿带 华南加里东期碰撞造山 碰撞后伸展构造背景
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新中国成立初期上海邮政组织体制调整初探(1949-1960)
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作者 李家涛 《上海经济研究》 北大核心 2025年第8期118-128,共11页
1949-1960年上海邮政系统进行了持续的范围较广的组织体制调整,试图通过组织体制调整,来提高企业管理水平,推动上海邮政持续发展。上海邮政系统组织体制调整的实质是通过组织调整探索并推进邮政企业治理体系建设,提升企业治理能力。上... 1949-1960年上海邮政系统进行了持续的范围较广的组织体制调整,试图通过组织体制调整,来提高企业管理水平,推动上海邮政持续发展。上海邮政系统组织体制调整的实质是通过组织调整探索并推进邮政企业治理体系建设,提升企业治理能力。上海邮政以频繁的组织体制调整推动企业治理体系建设和治理能力提升的尝试,不仅未能取得预期成效,反而因组织体制调整不合理,导致上海邮政系统出现管理层次多、机构职责划分不清晰、非直接生产人员编制庞大等不利于企业持续发展的问题。1949-1960年上海邮政组织体制调整历程表明,新中国成立初期邮政系统企业治理体系建设尚处于摸索阶段,既未形成治理体系思维,也未认识到企业治理体系建设是一项系统工程。 展开更多
关键词 新中国成立初期 上海邮政 组织体制调整 企业治理体系
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