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NETS IN MULTISYSTEMS OF n+3 AND n+4 PHASES

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Science in China,Ser.B 1982年第8期25卷 893-904页

作者：林传仙张哲儒白正华 institute of geochemistry academia sinica guiyang

From the free energy surfaces in G-p-T space a series of basic characteristics have beensummarized. For the reactions of most systems with phases of constant composition, eachof the surfaces should be approximate to a plane. After they meet, the points, curves andsurfaces possess distinct stability levels. Across the intersecting curves and points, the freeenergy surfaces and curves will change their stability levels. Linking invariant points ofdistinct stability levels, we can get various univariant curves differing in structure. Theangular extent between two univariant curves around the invariant points is less than 180°.The surfaces meeting in space and projecting onto the p-T section will give rise to partiallyclosed or open, rather than completely closed nets. Finally, based upon the basic characteristicsand criteria, we have derived the partially closed nets of n+3 and n+4 phases with maxi-mum closure by using geometrical and analytical methods. From the free energy surfaces in G-p-T space a series of basic characteristics have beensummarized. For the reactions of most systems with phases of constant composition, eachof the surfaces should be approximate to a plane. After they meet, the points, curves andsurfaces possess distinct stability levels. Across the intersecting curves and points, the freeenergy surfaces and curves will change their stability levels. Linking invariant points ofdistinct stability levels, we can get various univariant curves differing in structure. Theangular extent between two univariant curves around the invariant points is less than 180°.The surfaces meeting in space and projecting onto the p-T section will give rise to partiallyclosed or open, rather than completely closed nets. Finally, based upon the basic characteristicsand criteria, we have derived the partially closed nets of n+3 and n+4 phases with maxi-mum closure by using geometrical and analytical methods.

关键词： NETS IN MULTISYSTEMS OF n+3 AND n+4 PHASES line

A Comprehensive Evaluation on the Devonian-Carboniferous Boundary Stratotype Candidate Section in Nanbiancun, Guilin, Guangxi

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Acta Geologica sinica(English Edition) 1990年第1期64卷 69-79页

作者： Yu Changmin Nanjing institute of Geology and Palaeontology, academia sinica 2This paper is extracted from some relevant chapters of a monograph. The authors who wrote the monograph are: Yu Changmin Ruan Yiping Xu Hankui Wang Shangqi Zhu Zhaoling Mu Xinan Wang Keliang Yin Bao' an Li Zhengliang Li Yukuan Guo Shuying Yao Zhaogui He Guiying Zhang Yue'e Lu Hongjin Huang Zhicheng Zhu Sizhao Yang Jiedong Wang Yinxi Ye Sujuan and Xu Tongchun.

This paper presents a comprehensive evaluation on the Devonian-Carboniferous Boundary (DCB) sectionin Nanbiancun. Guilin. Guangxi on the basis of Palaeontological, biostratigraphical and sedimentarypetrological studies as well as microfacies analysis. REE and trace element analysis and isotopic dating. The DCB at this section conforms to the definition of this boundary and essentially measure up the criteriaand conditions for selection of the boundary stratotype. Up to 14 fossil groups are contained in the section. Thesection presents a general biostratigraphical framework with multispecies fossils zones, assemblage zones andmultiple groups of fossils and has latent preponderant conditions for magnetostratigraphic andchronostratigraphic studies. The boundary and point occur in a persistent and continuous monofacialcarbonate succession. and the section is located in a tourist city with convenient communication, where variousfacies of DCB sections are developed. allowing the correlation within a small area. So it is an ideal candidateboundary stratotype.

关键词： Guilin Guangxi A Comprehensive Evaluation on the Devonian-Carboniferous Boundary Stratotype Candidate Section in Nanbiancun

DISCREPANCY IN SOUND POWER DETERMINATION AT LOW FREQUENCIES

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Chinese Journal of Acoustics 1989年第2期8卷 97-110页

作者： MAA Dah-You( institute of Acoustics , academia sinica ) Acad sinica

The determination of the sound power of a source is simple in a reverberation chamber , but usually lower valves are obtained at low frequencies than the free - space value . It is shown that the sound power determined in a reverberation chamber depends not only on its free - space power , but also on the positions of the source and the reveiver , as well as the way the measurements are made and averaged . Exact and statistical formulas are derived to account for these factors . The results explain the discrepancy and agree well with earlier experiments . Based on the theory ,parcticable techniques of sound power determination are proposed and correct power formulas presented .

关键词： DISCREPANCY IN SOUND POWER DETERMINATION AT LOW FREQUENCIES

THE CHARACTERISTICS AND MODELLING EXPERIMENTS ON THE DEPOSIT-CONTROLLING STRUCTURE OF SHEAR-ZONE GOLD DEPOSIT IN CHINA

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Geotectonica et Metallogenia 1996年第Z1期20卷 31-33页

作者： Wu Xueyi(institute of geochemistry, academia sinica, guiyang, 550002, China)

THE CHARACTERISTICS ANDMODELLING EXPERIMENTS ON THEDEPOSIT-CONTROLLING STRUCTUREOF SHEAR-ZONE GOLD DEPOSITIN CHINAWu Xueyi(institute of geochemistry, academia sinica, guiyang, 550002, China)shear zone, gold-controlled structure, modelling experimentThe shear-zone gold deposits found in China can be divided into four types: (1) gold deposits controlled by the ductile shear-zones; (2) gold deposits controlled by the brittle-ductile shear zones; (3) gold deposits conntrolled by the ductile-brittle shear zones; (4) gold deposits controlled by the brittle shear zones. These gold deposits mostly occurred in the regions with higher abundance of gold, which underwent a long and complicated evolution-ary process and had obvious zoning and multiperiod metallogenic feature. The modelling exper-imental result of gold-controlled structure shows that the thermodynamics of compresso-shear structures made gold mobilizing and migrating in the earlier stage of shear zone; and that the extension process did

关键词： shear zone gold-controlled structure modelling experiment

Advances in geochemical research on nanometer materials

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Progress in Natural Science:Materials International 2006年第4期16卷 331-337页

作者： ZHU Xiaoqing and WANG Zhonggang Key Laboratory of Ore Deposit geochemistry, institute of geochemistry, Chinese Academy of Sciences, guiyang 550002, China Key Laboratory of Ore Deposit geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Important advances have been made in the field of geochemistry since nanometer science and technology were introduced into the field of geoscience. The nanometer particulates have been discovered in naturally-occurring ore deposits, volcano-eruptive materials and geo-gases, and a more detailed exploration of the metallogenic mechanism of endogenic metallic ore deposits has been conducted. It is considered that some ore-forming metals may transport in the form of native particulates. Because they have very strong capabilities of adsorption, adsorption is always regarded as an important mechanism of metallogenesis under supergenic and low temperature conditions. Therefore, a new technology of ore exploration has also been developed. This paper attempts to review the new advances in geochemical research on nanometer materials, as well as its perspectivess.

关键词： nanometer geochemistry adsorption metallogenic theory prospecting method.

H-O ISOTOPE COMPOSITION OF SHANHAIGUAN MIAROLITIC ALKALINE GRANITE

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Chinese Science Bulletin 1989年第9期34卷 770-771页

作者：李培忠于津生 institute of geochemistry Academia Sinica Guiyang

The Shanhaiguan volcanic-intrusive ring complex is composed of alkaline-feldspar trachyte and pantellerite (125 MaBP), comenditical ignimbrite (123 MaBP),

关键词： isotope granite.

BACKSCATTERING ON A FINITE-LENGTH RIGID CIRCULAR CYLINDER DUE TO A NARROW SOUND BEAM

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Chinese Journal of Acoustics 1989年第2期8卷 148-156页

作者： XIE Yunbo and FENG Shaosong(institute of Acoustics ,academia sinica) Acad sinica

The geometrical theory of diffraction (GTD) ,combined with Fourier transformation, has been applied to the back - scattering on a finite - length rigid circular cylinder due to a narrow sound beam. The theoretical res... 详细信息

关键词： exp BACKSCATTERING ON A FINITE-LENGTH RIGID CIRCULAR CYLINDER DUE TO A NARROW SOUND BEAM

Dating Model of Illite Grain Rb-Sr Isochron and Its Application to Precambrian Stratigraphy

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Acta Geologica sinica(English Edition) 1989年第1期63卷 93-102页

作者： Li Yunjun institute of Geology, academia sinica, Beijing Jia Zhongpeng institute of Geology Academia Sinica Beijing

This paper discusses the Rb-Sr geochemical behaviour of illites in the sedimentary process, and points out that illites of the lmd and lm types could reach Sr-isotopic equilibrium with its environmental medium during the sedimentary process and initial stage of diagenesis, and illite grains of different sizes have various Rb contents. A new dating method for sedimentary rocks----a dating model of illite grain Rb-Sr isochron----is established, in consideration of the geochemical process of Sr-isotopic homogenization and differentiation in the course of their formation and evolution. In addition, the paper concerns the application of the dating model to the Precambrian unmetamorphosed sedimentary rocks in western Henan Province, which gives satisfactory results coincident with the geological facts.

关键词： Dating Model of Illite Grain Rb-Sr Isochron and Its Application to Precambrian Stratigraphy Sr Rb

TEMPERATURE DEPENDENCE OF FREQUENCY MEASUREMENT WITH SAW CZT PROCESSOR

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Chinese Journal of Acoustics 1989年第4期8卷 295-304页

作者： CHEN Dongpei and GONG Junjie(institute of Acoustics, academia sinica) Acad sinica

Usually,frequency measurement with SAW chirp Z transform processor is something temperature dependent because of performance changes of SAW chirp delay lines used in processor with temperature. Hence, a full knowledge of the temperature dependence is necessary for practical processor design and compensation. So far, as we know, no adequate quantitative analysis has been given. In this paper a theoretical model is set up for the analysis of temperature dependence of ferequency measurement with a SAW CZT processor based on time scale principle. A closed form expression is given to formulate the deviation of the measured frequency from the actual input when the temperature changes. The deviation is not only related with SAW time delay temperature coefficient of the substrate used in SAW device and the parameters of SAW chirp delay lines, but also with the input frequency. A good agreement between our experiment and theory is shown and a reasonable explanation is given to the discrepancy between Claude Lardat 's theory and experiment results by our theoretical model.

关键词： SAW CZT