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METALLOGENIC CHARACTERISTICS AND OREPROSPECTINGFUTURE OF PRECAMBRIAN GOLD DEPOSITSIN MUFUJIULING DISTRICT

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Journal of Central South university 1996年第1期8卷 11-13页

作者： Wu Yanzhi(department of Geology, Central South university of Technology,Changsha 410083,{2.) department of Geology Central South University of Technology Changsha 410083 China

MufuJiuling district is an important placer gold producing land since the ancient time. In recent years, some primary gold deposits and mineralizations, e. g., Huangjindong and Tulongshan gold deposits, have been found. But the metallogenic conditions and regularities as well as the oreprospecting future remain to be recognized. Through the study on the metallogenic background and condition, the auriferous source bed and the mineralizing characteristics, three types of primary gold deposits are confirmed to be prospective in this district and some key problems about their prospecting and evaluating are put forward.

关键词： primary gold deposit PreCambrian age metallogenic marker

Quasifusulina的旋壁构造及其在(竹蜓)类分类、演化中的意义

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微体古生物学报 1993年第2期10卷 159-166,241页

作者：杨湘宁郑洪南京大学地球科学系南京210008 中国地质大学北京100083

本文介绍作者利用扫描电子显微镜对(竹蜓)类Quasifusulina旋壁超微构造的初步研究结果。电镜观察表明,Quasifusulina旋壁的主要部分系由许多近等轴的方解石微粒构成,这些微粒有规律地叠置在一起,形成了一系列垂直于壳表、彼此相邻的方... 详细信息

本文介绍作者利用扫描电子显微镜对(竹蜓)类Quasifusulina旋壁超微构造的初步研究结果。电镜观察表明,Quasifusulina旋壁的主要部分系由许多近等轴的方解石微粒构成,这些微粒有规律地叠置在一起,形成了一系列垂直于壳表、彼此相邻的方解石复合体。尽管其光学特征与蜂巢层和透明层颇为相似,但从构成旋壁的方解石微粒的形状、大小及排列和定向方式来看,Quasifusulina旋壁的超微构造既明显地有别于典型的蜂巢层,也不同于典型的透明层。为便于描述,作者建议将Quasifusulina旋壁的这种特殊构造称为“原蜂巢层”(prokeriotheca)。根据电镜观察,Quasifusulina旋壁由原蜂巢层及不连续的内疏松层构成,它可能代表了?类有孔虫中一种独特的旋壁类型。这种旋壁构造在?类动物的分类及演化研究中可能具有重要意义。

关键词： Ting类化石超微构造

BOUNDED SOLUTIONS AND PERIODIC SOLUTIONS OF VISCOUS POLYTROPIC GAS EQUATIONS

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Chinese Annals of mathematics,Series B 1997年第1期18卷 89-98页

作者： LUO TAO Institute of mathematics, Academia Sinica,Beijing 100080, china department of Applied mathematics Tsinghua University Beijing 100084 China

A piston problem of viscous polytropic gas equations is discussed. It is shown that the global solution is bounded uniformly in time if the piston motion is bounded and that if the piston motion is periodic in time, t... 详细信息

关键词： Viscous polytropic gas Uniformly bounded solution Periodic solution

ON ABSOLUTE STABILITY OF CONTROL SYSTEM WITH SEVERAL EXECUTIVE ELEMENTS

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Science in china,Ser.A 1988年第4期31卷 395-405页

作者：赵素霞 department of mathematics Liaoning Normal university Dalian

In this paper, we study the absolute stability of control system with several executive elements by means of Liapunov’s functions of the Lur’e form. We obtain some necessary and sufficient conditions for V<0. From these conditions we obtain a very general algebraic criterion for absolute stability. An effective computational procedure is given, which is applicable to all cases when the existence of absolute stability may be established by this type of Liapunov’s function. Furthermore, the stability region in the parameter space is defined by the obtained conditions, the region of which contains that defined by the Popov frequency criterion.

关键词： absolute algebraic executive criterion Liapunov applicable independence arbitrary assume suppose

Mathematical Delineation of the Thermophysical Process of Electron Beam Welding

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稀有金属材料与工程 2011年第S4期40卷 134-137页

作者： Wang Xuedong1,2.Fu Pengfei 1,Shi Qingyu 2.1National Key Laboratory of Science and Technology on Power Beam Processes,Beijing Aeronautical Manufacturing Research Institute,Beijing 10002.,china2.department of Mechanical Engineering,Tsinghua {2.,Beijing 100084,china Beijing Aeronaut Mfg Res Inst Natl Key Lab Sci & Technol Power Beam Proc Beijing 100024 Peoples R China Tsinghua Univ Dept Mech Engn Beijing 100084 Peoples R China

Multiple factors and complicated coupling relationships exist in the weldment during EBW,in order to comprehend this process,a mathematical delineation method based on a main line was presented in this *** on the main line,the complicated coupling relationships existing in EBW were reproduced by mathematical *** calculational results were in well agreement with the experimental *** mathematical delineation was an effective method to comprehend the features and essence of EBW.

关键词： electron beam welding mass transfer identification of phase interface keyhole

Composition of sandstone and heavy minerals implies the provenance of Kuqa Depression in Jurassic, Tarim basin, china

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Progress in Natural Science:Materials International 2005年第7期15卷 633-640页

作者： WU Chaodong, LIN Changsong, SHEN Yanping and FENG Xue ( Key Laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education, Peking university, Beijing 100871, china {2. of Resources, china university of Geosciences, Beijing 100083, china) Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education Peking University Beijing 100871 China. department of Resources China University of Geosciences Beijing 100083 China

The petrological characteristics and heavy mineral assembly of the Jurassic System in Kuqa Basin are consistent with the tectonic evolution, which is the major factor controlling the filling process of Kuqa Basin. Controlled by the source areas at the both sides of the Basin, the matrixes are dominated by sedimentary rock, high-grade metamorphic rock, acid magmatic rock, and the highest heavy mineral assemblage of zircon-garnet-magnetite in the content. According to heavy mineral indexes, the Jurassic strata can be classified into three rhythmic units of heavy mineral. The lower sequence contains abundant heavy minerals and relatively high content of detritus and its matrixes primarily came form the recycling orogen. The assemblage of "zircon-garnet-magnetite" indicates that the sedimentary area in the early evolution period of the basin is relatively near the provenance. The middle sequence is different from the lower sequence in the heavy mineral assemblage and has the different characteristics from that of source rock. The heavy mineral assemblage is "garnet-zircon" with the highest content of garnet and its main matrices are the high-grade metamorphic rock, acid magmatic rock and hydrothermal vein at the northeastern edge of the basin. The middle and upper sequences are characterized by the clast provenance, which is primarily from the recycling orogen at the northern edge of the basin and secondarily from the southern uplift. As a result of the two provenances, the strata with apparent changes of heavy mineral assemblage and index better coincides with the interfaces of the secondary strata sequences, which reflects the denudation history and the filling process of the orogen at the northern edge of the basin.

关键词： sandstone components provenance analysis filling sequence tectonic evolution.

DETERMINANT SOLUTIONS OF THE NONAUTONOMOUS DISCRETE TODA EQUATION ASSOCIATED WITH THE DEAUTONOMIZED DISCRETE KP HIERARCHY

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Journal of Systems Science & Complexity 2010年第1期23卷 153-176页

作者： Satoshi TSUJIMOTO department of Applied mathematics and Physics Graduate School of InformaticsKyoto University

It is shown that the nonautonomous discrete Toda equation and its Backlund transformation can be derived from the reduction of the hierarchy of the discrete KP equation and the discrete two-dimensional Toda equation. Some explicit examples of the determinant solutions of the nonautonomous discrete Toda equation including the Askey-Wilson polynomial are presented. Finally we discuss the relationship between the nonautonomous discrete Toda system and the nonautonomous discrete Lotka- Volterra equation.

关键词： Askey-Wilson polynomial Darboux transformation discrete KP hierarchy nonautonomous discrete Lotka-Volterra equation nonautonomous discrete Toda equation.

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努力提高我国数学教育专业研究生的培养水准

数学教育学报 2003年第1期12卷 7-11页

作者：郑毓信南京大学哲学系江苏南京210093

研究生的培养应以理论学习为重点,着眼于知识的拓宽,强调专业知识的必要重组;与“方法至上”相对立,应当更为重视论题的选择;要由唯一强调定量分析转为重视定性分析,由“心理学研究模式”逐步转向“人类学研究模式清醒的自我意识与自觉... 详细信息

研究生的培养应以理论学习为重点,着眼于知识的拓宽,强调专业知识的必要重组;与“方法至上”相对立,应当更为重视论题的选择;要由唯一强调定量分析转为重视定性分析,由“心理学研究模式”逐步转向“人类学研究模式清醒的自我意识与自觉的反思则可被看成提高研究能力的重要途径.

关键词：数学教育专业研究生培养自我意识中国定性分析选题

Further decomposition for singular systems and its properties on geometric subspace

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控制理论与应用（英文版） 2010年第3期8卷 293-300页

作者： Jianxiong YANG, Maoqing LI (department of Automation, Xiamen university, Xiamen Fujian 361005,{2.) department of Automation Xiamen University Xiamen Fujian China

This paper focuses on the relationship between the geometric subspaces and the structural decomposition of continuous-time singular systems. The original structural decomposition is not capable of revealing explicitly the invariant geometric subspaces for singular systems. As such, a further decomposition is necessary and is thus investigated in this paper. Under a new decomposition proposed, the supremal output-nulling （A, E, ImB）-invariant subspace of singular systems can be clearly expressed in an explicit form, and some of its applications are also addressed.

关键词： Singular systems Structural demonstration Geometric subspaces