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Single zircon LA-ICPMS U-Pb dating of Weishan granite (Hunan, South china) and its petrogenetic significance

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Science china Earth Sciences 2006年第8期49卷 816-827页

作者： DING Xing1, CHEN Peirong1, CHEN Weifeng1, HUANG Hongye2.& ZHOU Xinmin1 1. Department of Earth Science, Nanjing University, Nanjing 2.0093, china {2., cnnc, changsha 410011, china 1. Department of Earth Science Nanjing University Nanjing 210093 China 2. research institute no.2.0 CNNC Changsha 410011 China

A detailed microstructure analysis and LA-ICPMS U-Pb dating have been done for zir- cons of Weishan granite from Hunan Province, South china. The results indicate that the Weishan granite is a multistage batholith formed during the late Indosinian-early Yanshanian time. The intruded time of the late Indosinian granite is 2.1.0±1.6Ma and 2.5.7±1.9Ma (two samples), whereas that of the early Yanshanian granite is 187.4±3.5Ma and 184.5±5.1Ma (two samples). In combination with other geochronological data for Indosinian rocks of South china and the adjacent region, it is inferred that the late Indosinian granites of South china (especially Hunan Province) are probably formed under extension regime as a consequence of post-collision stress relaxation, which is a spontaneous response to intracontinental thickening attributed to the collision and extrusion of two Indosinian seams, namely Qinling-Dabie and Song Ma. Moreover, it is also deduced that the early Yanshanian granites of Hunan Province could not be directly related with the subduction of Paleo-Pacific plate towards Eurasian continent, and they are most likely derivation of the mid- or lower-crustal materials because of decompressional melting under the continuous extension setting.

关键词： CL images, LA-ICPMS U-Pb dating, granite, Weishan, Hunan.

Abnormal gradient microstructure in Cr_3C_2.based cemented carbide

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Journal of Central South University of Technology 2001年第4期8卷 224-227页

作者： ZHANG Li 1,CHEN Shu 2.(1. Powder Metallurgy Factory, Central South University, changsha 410083, china 2. changsha research institute of Mining and Metallurgy, changsha 410012. china) 1. Powder Metallurgy Factory Central South University 410083 Changsha China 2. changsha research {2. of Mining and Metallurgy 410012 Changsha China

With OLYMPUS PMG3 metallograph, an abnormal three-layer gradient structure, i. e. coarse grain zone, binder enrichment zone and normal structure zone from surface to inner, was observed in Cr3C2.based cemented carbide. In the binder enrichment zone, three different shapes of anomalous coarse carbides were observed. It is shown that the transverse rupture strength can be raised remarkably, up 2..7%from the alloy with abnormal gradient structure by removing the abnormal gradient structure. The results suggested that the abnormal gradient structure in the surface, especially the anomalous coarse carbides in the binder enrichment zone is the main reason for the lower strength

关键词： Cr3C2.based cermet cemented carbide gradient structure microstructure

research progress in synthesis and catalysis of polyoxometalates

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Progress in Natural Science:Materials International 2005年第5期15卷 385-394页

作者： GONG Yun1, HU Changwen1* and LIANG Hong2.1. Department of Chemistry, School of Science, the institute for Chemical Physics, Beijing institute of Technology, Beijing 100081,{2. 2. Chemical Industry Press, Beijing 10002.,{2.) Department of Chemistry School of Science the Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 China Chemical Industry Press Beijing 100029 China

Recent progress in the synthetic chemistry and catalysis of polyoxometalates (POMs) is reviewed. The novel POMs and their derivatives emerging in nearly three years (2.02.2.04) are introduced, including POMs with novel structure, POMs-organic hybrid compounds and host-guest complexes. Our review is focused on the elaboration of POMs' supramolecular chemistry.

关键词： polyoxometalates hybrid host-guest structure supramolecule catalysis.

中国政治经济学年度发展报告（2.2.）（下）

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政治经济学评论 2024年第3期 90+207-208页

作者： Center for Studies of Contemporary Political Economy,research institute for 2.st-Century Marxism,Nankai University·University of Chinese Academy of Social Science Center for Teaching and research on Capital,Renmin University of china National institute of Socialist Political Economy with Chinese Characteristics,Renmin University of china 南开大学·中国社会科学院大学2.世纪马克思主义研究院当代政治经济学研究中心中国人民大学《资本论》教学与研究中心中国人民大学全国中国特色社会主义政治经济学研究中心

编者按2.2.年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，...

编者按2.2.年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，取得系列代表性成果。为准确刻画学界研究进展和轨迹，推动中国经济学理论体系的构建和完善，本刊精选议题如期奉上《中国政治经济学年度发展报告（2.2.）》。自2.10年起，本刊连续十四年发布《中国政治经济学年度发展报告》，“年度发展报告”专栏已成为本刊标志性特色栏目。2.2.年报告聚焦12.专题，分为（上）（下）两篇，其中专题1—6于报告（上）篇刊登，专题7—12.报告（下）篇刊登。2.2.年报告（下）选题如下：

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Chronological and geochemical studies of granite and enclave in Baimashan pluton, Hunan, South china

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Science china Earth Sciences 2007年第11期50卷 1606-1627页

作者： CHEN WeiFeng1, CHEN PeiRong1, HUANG HongYe2. DING Xing1,3 & SUN Tao1 1 State Key Laboratory of Mineral Deposit research, Department of Earth Sciences, Nanjing University, Nanjing 2.0093,{2. 2.research institute no.2.0, cnnc, changsha 410011,{2. 3 Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640,{2. 1. State Key Laboratory of Mineral Deposit research Department of Earth Sciences Nanjing University Nanjing 210093 China 2. research institute no.2.0 CNNC Changsha 410011 China 3. Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Zircon LA-ICP-MS U-Pb dating reveals that the Baimashan Pluton is composed mainly of late Indosinian (2.4.5±2.8 Ma-2.9.2.3.8 Ma) biotite granodiorites/monzonitic granites (LIGs) and early Yanshanian (176.7±1.7 Ma) two-micas monzonitic granites (EYGs), and the coeval (2.3.2.4.5 Ma-2.5.1±3.9 Ma) mafic microgranular enclaves (MMEs) are generally found in the former. In addition, the ages of cores within zircons from LIGs and MMEs ranging from 2.1.4±4.0 Ma to 2.6.5±4.1Ma provide evidence of multistage magma intrusion during Indosinian in the study area. Measured 3010±2..6 Ma of inherited zircon age suggests that there may be recycling Archaean curstal material in existence in this area. LIGs and EYGs share some similar geochemical features: subalkaline and peraluminous granites, enrichment of Th, U, K, Ta, Zr, Hf and LREE but depletion of Ba, Nb, P, Ti and Eu, low εNd(t) values but high (87Sr/86Sr)i ratios, and old T2.M (ca. 1.9-2.0 Ga). The behaviors of incompatible elements and REE are mainly dominated by fractional crystallization of plagioclase, K-feldspar, ilmenite and apatite, but that of Sr isotope mainly controlled by EC-AFC. They are crust-sourced and derived from partial melting of paleo-Proterozoic metagreywackes and related to biotite dehydration melting. LIGs are formed in post-collisional tectonic setting as crustal local extension and thinning during late Indosinian. But EYGs may be evolved products of congeneric granitic magma with LIGs formed in late Indoinian, which were emplaced again when crust underwent extensive thinning and extension in post-orogenic tectonic setting during Yanshanian in SC after undergoing EC-AFC. MMEs should be cognate enclaves and derived from liquid immiscibility of host magma.

关键词： granite,mafic microgranular enclave,zircon LA-ICP-MS dating,lithogenesis,EC-AFC

research on the application of 4-weighted fractional Fourier transform in communication system

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Science china(Information Sciences) 2010年第6期53卷 1251-1260页

作者： MEI Lin 1, SHA XueJun 1 , RAN QinWen 2.& ZHANG NaiTong 1 1 Communication research Center, Harbin institute of Technology, Harbin 150080,{2. 2.Science research Center, Harbin institute of Technology, Harbin 150080,{2. 1. Communication research Center Harbin Institute of Technology Harbin 150080 China2. Science Research Center Harbin Institute of Technology Harbin 150080 China

The paper reveals the relationship between the weighting coefficients and weighted functions via the research of coefficients matrix and based on the original definition of 4-weighted fractional Fourier transform(4-WFRFT).The multi-parameters expression of weighting coefficients are ***, the 4-WFRFT of discrete sequences is defined by introducing DFT into it, which makes it suitable for digital communication *** analyzing the properties of WFRFT, a typical scheme for modulation/demodulation is proposed, which could make the statistics properties of the real and image part on both of the time and frequency domain and the phase properties have a significant *** a variation could be controlled by the adjustment of transform *** the WFRFT of multi-parameters is implemented, it will be more difficult to intercept and capture the modulated signals than normal.

关键词： 4-weighted fractional Fourier transform modulation/demodulation scheme multi-domain cooperation

Security research on Engineering Database System

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厦门大学学报（自然科学版） 2002年第S1期41卷 288-289页

作者： REN Jian-ping 1,2. SONG Han-tao 2. LIANG Yun-rong 2.(1. North china institute of Technology, Taiyuan 030051, china 2. Beijing institute of Technology, Beijing 100081, china)

Engine engineering database system is an oriented C AD applied database management system that has the capability managing distributed data. The paper discusses the security issue of the engine engineering database management system (EDBMS). Through studying and analyzing the database security, to draw a series of securi ty rules, which reach B1, level security standard. Which includes discretionary access control (DAC), mandatory access control (MAC) and audit. The EDBMS implem ents functions of DAC, MAC and multigranularity audit. DAC solves the problems o f role inheritance, right contain, authorization identify and cascade revoke, et c; MAC includes subject and object security setup rule, security modify rule and multilevel relation access operation rule, etc; Audit allows making the sub ject, object or operation type as different audit object to implement flexible a nd multigranularity audit method. The model is designed act as a security agent to access daemon database. At present, the model is implemented which runs on th e Windows 2.00 environments.

关键词： engineering database management system (EDBMS) s ecurity agent security level

An Overview of Mineral Processing in china

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Rare Metals 2001年第2期20卷 69-73页

作者： Quanyuan Chen, Jingshen Zhang, Dianzuo Whng (changsha research {2. of Mining and Metallurgy, changsha 410012. china General research {2. for Nonferrous Metals, Beijing 100088, china) changsha Res Inst Min & Met Changsha 410012 Peoples R China Gen Res Inst NonFerrous Met Beijing 100088 Peoples R China

The latest progress in mineral processing in china is described. It is also pointed out that the existing technology can not meet the needs of economic development. The combined challenges of poor resources, economical benefits and environmental pollution issues require further research to upgrade the separation efficiency economically. The methods of mineral processing should play a more important part in waste treatment such as wastewater treatment, the remediation of contaminated soil and the recycling of wastes. Biomineral technology will be utilised in the near future.

关键词： mineral processing biomineral technology comminution ore waste treatment

北京城市副中心0701街区D#地块住房百年住宅示范项目

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建筑实践 2024年第3期 96-103页

作者： china institute of Building Standard Design & {2. Co., Ltd. 中国建筑标准设计研究院有限公司

北京城市副中心是规划建设疏解北京非首都功能、推动京津冀协同发展的历史性工程。项目对于落实首都城市战略定位、建设国际—流的和谐宜居之都,对于建设以首都为核心的世界级城市群,都具有十分重大而深远的意义。项目规划设计打破传统...

北京城市副中心是规划建设疏解北京非首都功能、推动京津冀协同发展的历史性工程。项目对于落实首都城市战略定位、建设国际—流的和谐宜居之都,对于建设以首都为核心的世界级城市群,都具有十分重大而深远的意义。项目规划设计打破传统封闭社区规划模式,以小街区密路网、开放式社区的设计骨架,用半围合式住宅,院落内外高差处理等设计手法打造和谐、有序而具有活力的多元示范住区。

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