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A New Chiral Synthesis of Naturally Occurring (-)-(S)-4-Hydroxy-2.pyrrolidinone

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Chinese Chemical Letters 1999年第9期10卷 735-736页

作者： Pei Qiang HUANG Xiao ZHENG Shi Li WANG Jian Liang YE Li Ren JIN(department of Chemistry, xiamen university, {2., Fujian 361005) xiamen Univ Dept Chem Fujian 361005 Peoples R China

A new and convenient chiral synthesis of naturally occurring (-)-(S)-4-hydroxy-2.pyrrolidinone from (S)-malic acid was reported.

关键词： (S)-malic acid (-)-(S)-4-hydroxy-2.pyrrolidinone ionic hydrogenation

Water gas shift activity of Co-Mo/MgO-Al_2._3 catalysts presulfided with ammonium sulfide

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Journal of Natural Gas Chemistry 2010年第1期19卷 61-66页

作者： Yixin Lian, Huifang Wang, Weiping Fang, Yiquan Yang department of Chemistry, College of Chemistry and Chemical Engineering, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, xiamen university,{2., Fujian, china [a] department of Chemistry College of Chemistry and Chemical Engineering National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters Xiamen University Xiamen 361005 Fujian China

Co-Mo/MgO-Al2.3 catalyst was presulfided with ammonium sulfide in aqueous solution and activated with synthesis gas for water gas shift reaction. The assay results indicate that the presulfided Co-Mo/MgO-Al2.3 catalyst exhibits an excellent catalytic activity and stability. XRD and EPR characterization results show that the O-S exchange might occur during the impregnation, leading to the formation of （NH4）2.oS4 （or （NH4）zMoxSy） precursor, which was then thermally decomposed and reduced to MoS2. The higher catalytic performance is attributed to an optimization formation of active Co-Mo sulfides, consisting of well dispersed MoS2.and Co-Mo-S phase due to the redispersion of Co sulfide particles over the edges of newly formed MoS2.crystallites.

关键词： Co-Mo-based catalyst ammonium sulfide presulfidation water-gas shift

A simple solvothermal route towards the morphological control of ZnO and tuning of its optical and photocatalytic properties

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Science china Chemistry 2010年第8期53卷 1711-1717页

作者： JIANG YaQi,LI FangFang,SUN Ran,XIE ZhaoXiong & ZHENG LanSun State Key Laboratory for Physical Chemistry of Solid Surfaces department of Chemistry,College of Chemistry and Chemical Engineering,xiamen {2.,xiamen 361005,china 1. State Key Laboratory for Physical Chemistry of Solid Surfaces department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

ZnO nanoparticles with different morphologies were solvothermally synthesized by controlling the alkali (sodium hydroxide) concentration in an isopropanol *** products were characterized by means of powder X-ray diffraction,UV-visible absorption spectra,scanning electron microscopy,transmission electron microscopy,and selected area electron *** morphologies of the formed ZnO nanocrystals were dependent on the concentration of the alkali,and with increases of sodium hydroxide concentration,the ZnO nanocrystals evolved from rod to hexagonal bipyramid,and then to a flower-like *** flower-like nanostructure resulted from the etching of the hexagonal bipyramid by the excess *** photoluminescence and photocatalytic properties of the prepared ZnO were *** difference of green emission among the ZnO nanocrystals indicated that a higher sodium hydroxide concentration led to a higher level of *** size,the surface structure and defects in the ZnO nanocrystals affected its photo-degradation characteristics.

关键词： zinc oxide solvothermal method nanocrystal photoluminescence photocatalysis

Artificial Neural Networks Applied to Gas Mixture Analysis

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Chinese Chemical Letters 1997年第7期8卷 623-626页

作者： Yong Jing LIN Er Yi ZRU Peng Yuan YANG(The Laboratory of Analytical Science,xiamen university{2.) xiamen UNIV SCI ANALYT LABXIAMEN 361005PEOPLES R CHINA

An array composed of sixteen gas sensors was constructed to analyze gas mixtures quantitatively. The data of responses from the sensor array to ethane, propane and propylene were treated by three-layer ANN with BP algorithms and PLS. The analytical results indicated that the concentration predicted with ANN is better than that with PLS. The average prediction errors for ethane, propane and propylene were 5.11%, 8.2.%, 2.64%, respectively.

关键词： Wang Artificial Neural Networks Applied to Gas Mixture Analysis

Measurement of ^(2.4)Ra, ^(2.6)Ra and ^(2.8)Ra in seawater using Mn-fiber adsorption-γ spectrum method

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Acta Oceanologica Sinica 2000年第2期19卷 19-27页

作者： Liu Guangshan1 Huang Yipu1 Chen Xinbao1 (1. department of Oceanography, xiamen university,{2., china) department of Oceanography Xiamen University Xiamen 361005 China

The specific activities of ^(2.4) Ra, ^(2.6)Ra and ^(2.8)Ra were determined by measuring γ-ray of their daughters with HPGe γ spectrometer after preconcentrating Ra isotope with Mn-fiber adsorption from large volume seawater. The calculating formulas of specific activities of the three nuclides were de rived. The methods of sample preparation and spectrum analysis were discussed. The advantages of the method are simple, rapid and three nuclides can be determined simultaneously.

关键词： Radium isotopes seawater γ-spectrum analysis

Composition and ecological distribution of ichthyoplankton in eastern Beibu Gulf

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Acta Oceanologica Sinica 2011年第1期30卷 94-105页

作者： ZHOU Meiyu LIN Yuanshao YANG Shengyun CAO Wenqing ZHENG Lianming College of Oceanography and Environmental Science Xiamen University Xiamen 361005 China State Key Laboratory of Marine Environmental Sciences （xiamen university） Xiamen 361005 China

Surveys were conducted in four seasons in the eastern Beibu Gulf from July 2.06 to November 2.07, to determine the ichthyoplankton composition, abundance, as well as environmental factors impacted on their spatiotemporal distributions. The fish eggs and larvae were sorted from 303 zooplankton quantitative samples, in which at least 1 order, 60 families, 31 genera and 61 species of fish eggs and larvae were identified. The species number was highest in summer whereas lowest in winter. With the most abundant fish egg （the average density was 2.41 ind./m3）, spring was the main spawning season, while the greatest mean density of fish larva was 1.35 ind./m3 in summer. In the whole year around, fish eggs had the trends to aggregate in the nearshore of Guangxi coast, fish larvae were more abundant in the northern water. Relationships between fish eggs and larvae abundance and environmental factors were analyzed by using the Yield-Density model. The spatio- temporal distribution of ichthyoplankton in eastern Beibu Gulf was closely related to the Chl a concentration, and the optimal temperature, salinity and Chl a were 19.4-2..7℃, 31.8-33.1 and 1.5-4.8 mg/m3, respectively. Additionally, the distribution of fish larvae could be effected by ocean currents in summer and autumn.

关键词： Beibu Gulf fish eggs fish larvae abundance distribution

Tracing　technique　of　stable　^（15）N　isotope：　an　application　in　study　of　mariculture

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Acta Oceanologica Sinica 1995年第1期14卷 39-45页

作者： Hong Ashi Li Wenquan and Wang Mingliang(Third Institute of Oceanography, State Oceanic Administration, xiamen 361005, china)({2. of Oceanography, xiamen university, xiamen 361005, china) Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China

Using Na15NO3 and 15NH4Cl as tracer, we studied the transfer of 15N along the food chain composed oforganisms such as Platymonas subcordiformis, Artemia salina, Penaeus penicillatus and Liza carinatus . The abundanceand atomic percentage of 15N in each organism, as well as the transfer of 15N among different biological phases weremeasured. Results show that, in the nutrient transfer from low level to high level along the md chain in the mediaof 15NH4Cl, the transfer rate of Artemia salina→Liza carinatus exceeded 3% and was higher than that in Na15NO3; the accumulation of 15N in the bodies of Liza carinatus with 15NH4Cl as media was also higher than that withNa 15NO3 as media.

关键词： Stable isotopic tracing food chain material circulation mariculture ecology

A　NOVEL　REARRRANGEMENT　OF　as-TRIAZOLIUM　SALT　TO　5-AMINOIMI　DAZOLE　DERIVATIVE

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Chinese Chemical Letters 1995年第9期6卷 743-744页

作者： Hong Kui ZHANG(department of Chemistry, xiamen university, {2., 361005)

Abstract: The rearrangement of as-triazolium salt (1) to 5-amino-1(2.4-dichloro) benzyl-4-(2.2.imethyl) propionylimidazole (2. with NaH in dimethylformmide(DMF) is described.

关键词： as-TRIAZOLIUM OF SALT REARRRANGEMENT TO AMINOIMI DAZOLE

CLASSIFICATION OF SOLUTIONS FOR A CLASS OF SINGULAR INTEGRAL SYSTEM

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Acta Mathematica Scientia 2011年第4期31卷 1449-1456页

作者：许建开谭忠 College of Sciences Hunan Agriculture University School of Mathematical Sciences Xiamen University

In this paper, we consider the following integral system： u（x） = R n v q （y）｜ x y ｜ nα dy, v（x） = R n u p （y）｜ x y ｜ nμ dy, （0.1） where 0 〈 α, μ 〈 n; p, q ≥ 1. Using the method of moving planes... 详细信息

In this paper, we consider the following integral system： u（x） = R n v q （y）｜ x y ｜ nα dy, v（x） = R n u p （y）｜ x y ｜ nμ dy, （0.1） where 0 〈 α, μ 〈 n; p, q ≥ 1. Using the method of moving planes in an integral form which was recently introduced by Chen, Li, and Ou in [2. 4, 8], we show that all positive solutions of （0.1） are radially symmetric and decreasing with respect to some point under some general conditions of integrability. The results essentially improve and extend previously known results [4, 8].

关键词： Hardy-Littlewood-Sobolev inquality integral equation moving plane interpolation inequality radial symmetry