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Molecular organic geochemical evidence for paleoenvironmental changes at 11.87—12.28 m in GS-1 sedimentary core,Gucheng Lake,East China

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Chinese Science Bulletin 1999年第15期44卷 1407-1411页

作者： Zhang, G Sheng, GY Fu, JM Wang, sm Chinese Acad Sci Guangzhou Inst Geochem State Key Lab Organ Geochem Canton 510640 Peoples R China Chinese Acad Sci Nanjing Inst Geog & Liminol Nanjing 210008 Peoples R China

Organic lipids with different occurrence modes in a sedimentary core in a subtropicalfreshwater lake, Gucheng Lake, were sequentially extracted, separated and analyzed. Thedown-core variations of OEP index of alkanes, C18:2/C18:0 ratios of fatty acids, ratios of boundfatty acids to free fatty acids, thermo-maturity indices of hopanoid hydrocarbons and relativeconcentrations of sedimentary minerals revealed an evident increasing in allochthonous inputfrom rock detritus below 12.28 m in the sedimentary profile. The distribution pattern of tightly-bound β-hydroxy fatty acids indicated a difference in bacterial communities above and below theboundary, as well as the gammacerane index may assign a significant change in lake watersalinity. The evidence, in general, suggested that a significant paleoenvironmental change hadtaken place in ca. 9.6 kaBP on the regional basis.

关键词： Gucheng Lake paleoenvironmental change molecular organic geochemical evidence.

Calculation of latent and sensible heat fluxes during summer in ocean area around Antarctic

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Chinese Science Bulletin 1997年第7期42卷 570-573页

作者： Li, sm Zhou, MY Su, LR Lu, NP National Research Center for Marine Environmental Forecasts Beijing China

THE transfer of latent and sensible heat fluxes over the ocean surface makes an important effect on the global climatic variation. The heat fluxes can be calculated directly by using the data of fluctuations of temper... 详细信息

关键词： Antarctic heat flux marine observation.

Electrochemical behavior of a series of azobenzene self-assembled monolayers on gold

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Chinese Science Bulletin 1997年第4期42卷 304-307页

作者： Wang, YQ Yu, HZ Cai, sm Liu, ZF BEIJING UNIV CTR INTELLIGENT MAT RESBEIJING 100871PEOPLES R CHINA

THE self-assembled monolayers (SAMs) emerged in the last decade as one of the most convenient and useful methods of preparing molecularly tailored interfaces with controlled spatial and geometric constraints, and have been examined widely from both fundamental and applied perspectives. Recently, SAMs of both unfunctionalized and redox-attached alkanethiols

关键词： self-assembled monolayers azobenzene electron transfer ion transfer.

Counting rational points on cubic curves

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Science China Mathematics 2010年第9期53卷 2259-2268页

作者： HEATH-brown Roger TESTA Damiano Mathematical Institute University of OxfordOxfordUK

We prove upper bounds for the number of rational points on non-singular cubic curves defined over the *** bounds are uniform in the curve and involve the rank of the corresponding *** method used in the proof is a com... 详细信息

关键词： cubic curves rational points counting function elliptic curves determinant method m-descent

The largest prime factor of the integers in an interval

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Science China Mathematics 1996年第5期39卷 449-476页

作者： D.R.Heath-brown Magdalen College University of OxfordOxford OXI 4AUUK

Let ε>*** is proved that the range (x,x+x1:2+ε) has such an integer that one of its prime factors p≥x11/12-ε

关键词： prime number sieve method asymptotic formula.

Solid state reaction of aromatic ketones with heteroaromatics

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Chinese Journal of Chemistry 1995年第6期13卷 520-524页

作者： Du, DM Meng, sm Wang, YM Meng, JB Zhou, XZ NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA YANBEI TEACHERS COLL DATONG 037000JILINPEOPLES R CHINA

The solid state reactions of p-nitroacetophenone, acetyl-ferrocene with indole were catalyzed by anhydrous zinc chloride or aluminum chloride, and gave exclusively the 1:2 condensation products. The solid state condensation of aromatic ketones with 1-phenyl-3-methyl-5-pyrazolone was also investigated, and the 1:1 and 2:1 condensation products were obtained. The structures of eleven new products were determined by IR, MS, H-1 NMR and elemental analysis.

关键词： solid state reaction aromatic ketone indole 1-phenyl-3-methyl-5-pyrazolone

A method of quantitatively calculating amount of allochthonous organic carbon in lake sediments

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Chinese Science Bulletin 1997年第21期42卷 1821-1823页

作者： Qian, JL Wang, sm Xue, B Chen, RS Ke, SZ Nanjing Inst Geog & Limnol Nanjing 210093 Peoples R China

TOTAL organic matter(TOM) or total organic carbon(TOC) is often treated as an importantindicator of lake environment. As a matter of fact, TOC is of multi-origin, and can simply bedivided into two parts: autochthonous and allochthonous organic carbon. The autochthonousorganic carbon is mainly controlled by the production of the plankton of lake itse1f; and the al-lochthonous one by climate and environment in the catchment area, e. g. more precipitationand runoff and densely developed vegetation will give rise to more allochthonous organic com-

关键词： lake sediment allochthonous organic carbon C/N.

Why Is Being Nothing?An Apophatic Reading of Hegel's Opening to the Science of Logic

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Frontiers of Philosophy in China 2018年第4期13卷 518-534页

作者： Nahum brown Department of Philosophy Sun Yat-sen UniversityZhuhai 519000China

The aim of this article is to analyze Hegel’s famous transition from being to nothing in the opening of the Science of Logic, to outline a variety of interpretations from commentators, and to defend what I call the “indirect apophatic interpretation” as support for the conclusion that Hegel is an ambiguously apophatic thinker. One benefit of the “indirect apophatic interpretation” is that it leads to a reassessment of Hegel’s conception of totality. The prevailing understanding of “totality” as exclusionary exhaustion, completion, and finitude has often been attributed to Hegel’s thought. But the “indirect apophatic interpretation” of the transition from being to nothing that I defend prepares the way for an alternative reading of totality in his work: not as the exhaustion of all positive content, but as the coincidence of being and nothing, as the contradiction A is -A, and as the exhaustion of form and content by way of a dialectic with the apophatic.

关键词： Hegel being nothing apophasis beginning

The Hoeke-brown failure criterion and GSI-2018 edition

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第3期11卷 445-463页

作者： E.Hoek E.T.brown North Vancouver British ColumbiaV7R 4H7Canada Brisbane Queensland 4169Australia

The Hoekebrown criterion was introduced in 1980 to provide input for the design of underground excavations in *** criterion now incorporates both intact rock and discontinuities,such as joints,characterized by the geological strength index(GSI),into a system designed to estimate the mechanical behaviour of typical rock masses encountered in tunnels,slopes and *** strength and deformation properties of intact rock,derived from laboratory tests,are reduced based on the properties of discontinuities in the rock *** nonlinear Hoekebrown criterion for rock masses is widely accepted and has been applied in many projects around the ***,in general,it has been found to provide satisfactory estimates,there are several questions on the limits of its applicability and on the inaccuracies related to the quality of the input *** paper introduces relatively few fundamental changes,but it does discuss many of the issues of utilization and presents case histories to demonstrate practical applications of the criterion and the GSI system.

关键词： Hoek-brown criterion Geological strength index(GSI) Rock mass strength Uniaxial compressive strength(UCS) Tension cut-off Rock mass deformation modulus