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A Study on Volatilization of Antimony and Bismuth by Heating with Ammonium Iodide——A Method for Separation and Determination of Trace Antimony and Bismuth in Geological Samples

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Acta Geochimica 1986年第3期 269-276页

作者：熊光平 institute of Geochemistry academia sinica

A decomposition apparatus was established consisting of a reaction tube and a long air-cooling conden-ser for the separation of antimony and bismuth through volatilization. It is demonstrated that the reactionSb;O;+6NH;I=2SbI;+6NH;+3H;O starts at 300℃ and completes at 380℃ in 8 min. In comparison,the reaction Bi;O;+6NH;I=2BiI;+6NH;+3H;O will not take place below 450℃ and will complete at550℃. The differences in volatilizing temperature between antimony and bismuth iodide are large enough tomake them separate at different temperatures. Experimental data show that antimony iodide was sublimatedat 380℃ without any loss of bismuth, and upon the completion of SbI;volatilzation the Iong condenser tubecan be substituted for by a clean one to collect volatilizing bismuth iodide at the temperature of 550℃.Results are in good agreement with those obtained from thermodifferential-thermogravimetric analyses. Determination of antimony was done using extraction spectrophotometric method with the reagent 5-Br-PADAP, and that of bismuth using spectrophotometric method with Xylenol Orange. The method isshople, rapid, accurate and suitable for rock and other geological samples containing antimony and bismuthin the range of X--X 10;ppm.

关键词： A Method for Separation and Determination of Trace Antimony and Bismuth in Geological Samples A Study on Volatilization of Antimony and Bismuth by Heating with Ammonium Iodide

ON THE LEAST PRIME IN AN ARITHMETICAL PROGRESSION(Ⅲ)

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Science China Mathematics 1989年第7期32卷 654-673页

作者：陈景润刘健民 institute of Mathematics Academia Sinica

Let D be a large integer, and P(D,K) the least prime in the progression {Dn + K:n∈ N, 0

关键词： the least prime arithmetical progression.

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CELL DIFFERENTIATION IN ASCIDIAN STUDIED BY NUCLEAR TRANSPLANTATION

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Science in China,Ser.A 1977年第2期 222-233页

作者：童第周吴尚懃叶毓芬李光三许梅青 institute of Oceanology academia sinica

The egg of the ascidian Ciona Intestinalis was divided 20 min after fertilization into two fragments, one nucleated and the other non-nucleated. Nucleus of ectodermal, mesodermal, or endodermal cell, taken from gastrula or tail-bud embryo was transplanted into the non-nucleated fragment. The fragment developed into abnormal or partial embryo, of which the cells or tissues were differentiated mainly according to the regional distribution of presumptive organ-forming substances of the egg cytoplasm that the fragment contained. The result indicated that differentiation of cells in ascidians was principally determined by the components of the mature egg eytoplasm, not by the transplanted nucleus, and the activity of the nucleus was, to some degree, controlled by the surrounding cytoplasm.

关键词： CELL DIFFERENTIATION IN ASCIDIAN STUDIED BY NUCLEAR TRANSPLANTATION

Instanton Effects on Gluon Propagator

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Communications in Theoretical Physics 2002年第10期38卷 449-454页

作者： FAN Xiao-Bin WANG Qing Department of Physics Tsinghua University Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 China institute of Theoretical Physics Academia Sinica Beijing 100080 China

Gluon propagator is investigated for pure Yang-Mills SU(3) gauge theory in field-strength approach. It isfound that instantohs provide a homogeneous solid-like medium background which generates finite nonzero momentum... 详细信息

关键词： gluon propagator, instanton

ON AMVLYSIPHONELLA ASIATICA ***.,A REMARKABLE SPONGE

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地质学报 1935年第1期 57-59+61-62+105页

作者：俞建章 Geological institute of academia sinica

In the Spring of 1933 *** obtained a remarkable fossil froma dark gray limestone probably of Permian (?) age in Kwangsi *** fossil was partly exposed on the weathered surface of the rock,and itsexternal form looks lik... 详细信息

关键词： A REMARKABLE SPONGE ON AMVLYSIPHONELLA ASIATICA SP.NOV

A NECESSARY AND SUFFICIENT CONDITION:BIHOLOMORPHIC MAPPINGS ARE STARLIKE ON A CLASS OF REINHARDT DOMAINS

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Chinese Science Bulletin 1991年第14期36卷 1151-1153页

作者：龚昇王世坤余其煌 University of Science and Technology of China Hefei 230026 PRC institute of Applied Mathematics Academia Sinica Beijing 100080 PRC

1. In [1], T. J. Suffridge gave the necessary and sufficient condition for local biholomorphic mappings on the Reinhardt domains , to be starlike. Using this condition Yu Qihuang et al. gave the growth theorem and covering theorem for normalized biholomorphic starlike mappings in D_p. In this note we give a necessary and suffident condition for local biholomorphic mappings on more general Reinhardt

关键词： biholomorphic mapping starlike mapping Reinhardt domains.

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NOTES ON COMPLEX MANIFOLDS AND ALGEBRAIC VARIETIES Ⅰ. PLūCKER’S FORMULA

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Science in China,Ser.A 1962年第5期 575-590页

作者：吴文俊 institute of Mathematics academia sinica

§1. Let C be a plane algebraic curve of degree m, then its genusis given by the following Plucker’s formula (cf. e.g. [6], p. 103): p=(m-1)(m-2)/2-d-s, (1.1) in which d is the number of 'double points', and s=Σ(k-1... 详细信息

关键词： PL CKER’S FORMULA NOTES ON COMPLEX MANIFOLDS AND ALGEBRAIC VARIETIES over 一砰

On the Conditions of Formation of Gushan Iron Ore Deposit

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Acta Geochimica 1984年第1期 45-55页

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

On the basis of its geological characteristics,the Gushan iron deposit should be assignedto voleano-hydrothermal type with hematite-quartz as its principal mineral *** of the ore solution has been estimated from the ratio of hematite to quartz inthe *** using experimental and thermodynamic data,the solubility of ferro-minerals atelevated temperatures and pressures have been calculated in the system FeO-Fe;O;-NaCl-HCl-H;*** effects of T,P,pH,fo;and total Cl concentration on the solubility of ferro-minerals are *** calculations based on presumed physieo-chemical con-ditions for the ore solution are in good *** geological *** calcula-tion shows that ferro-minerals were deposited at logfo;=-21～-25,log（mHCl+mH+）=-2.5～-3,P=1—0.75（or 0.5）kb,and T=400°—350℃.It is believed that the original solutionwas an acid NaCl-bearing solution of magmatic ***,iron in the solution wasenriched with falling temperatures by dissolving pre-existing ferro-minerals in consolidatedrocks rather than extracting directly from the *** temperature（below 400℃）orpressure decrease may result in the precipitation of ferro-minerals from the solution,but theFe/Si ratio in the ore is dependent mainly upon *** widespread siliceous veins of laterstages are a reflection of decreasing acidity of the *** increase in fo;will also favorthe deposition of *** hypabyssal occurrence and the existence of the Huang-maqing sandy shale have contributed greatly to the formation of hematite.

关键词： ferro solubility magma hydrothermal quartz extracting shale assemblage decreasing widespread

ON THE LEAST PRIME IN AN ARITHMETICAL PROGRESSION AND THEOREMS CONCERNING THE ZEROS OF DIRICHLET’S L-FUNCTIONS (Ⅱ)

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Science in China,Ser.A 1979年第8期 859-889页

作者：陈景润 institute of Mathematics academia sinica

First of all, let D be a large integer with (D, k)=1, and suppose that P(D, k) is the least prime in the progression {Dn + k). Further let L be a lower bound which satisfies P(D, k) << D~L, and we shall prove L≤ 17 i... 详细信息

关键词：一夕 ON THE LEAST PRIME IN AN ARITHMETICAL PROGRESSION AND THEOREMS CONCERNING THE ZEROS OF DIRICHLET’S L-FUNCTIONS