二安替比林对-(-2,4-二硝基苯氧基-)-苯基甲烷与铬显色反应的研究

合成新试剂二安替比林对 - (- 2 ,4-二硝基苯氧基 - ) -苯基甲烷 (DAp DNPPM) ,以正交试验设计寻找该试剂与微量 Cr( )显色反应的最佳显色条件。最佳条件为 :最大吸收波长 485 nm,显色剂 1.0 0 % DAp DNPPM用量 0 .6 0 ml,(1+4 ) H3 PO4用量 3.0 0 ml,0 .40 mol.L- 1 Mn( )用量 8.0 0 ml,加热温度 85℃ ,加热时间 8min。在 0 .10～ 0 .80μg/ 2 5 ml范围内呈现良好线性关系 ,线性回归方程为 :A =1.0 36 C (μg/ 2 5 ml) - 0 .0 0 8,r =0 .998。摩尔吸光系数为 1.30× 10 6L .mol- 1 .cm- 1 。用该法测定水样中 Cr ( )含量 ,结果满意。     

焦性没食子酸对硫化矿物的抑制性能和作用机理

研究了焦性没食子酸对硫化矿物浮选行为的影响及其作用机理，结果表明焦性没食子酸对方铅矿、黄铁矿、黄铜矿、闪锌矿具有抑制作用，对毒砂没有抑制作用，通过量子化学计算、亲固能计算以及能带结构分析等方法探讨了焦性没食子酸以硫化物的抑制机理。     

N,N-二正丁基硫代氨基甲酸镍的直接电化学合成

在单室电解池中，用牺牲阳极法，以二硫化碳和二丁基胺为原料，直接一步合成了N，N-二正丁基硫代氨基甲酸镍。研究了阴极电极材料、溶剂的种类和不同的电解质对反应影响，并讨论了电流密度和反应产率、电流效率的关系。适宜的反应条件为：镍作阴极、氢氧化钠为电解质、乙二醇为溶剂、电流密度为200mA/cm^2。这种合成方法具有步骤少、成本低、产物易分离等优点。     

The reaction of acenaphthene with nitrobenzene

The reaction of acenaphthene with nitrobenzene was investigated in the presence of AlCl₃. The results showed that the reaction proceeded via carboncation-electrophilic substitution reaction and free radical substitution reaction pathway. The products of acenaphthenyl phenylamine and biacenaphthyl could be synthesized by this reaction. The influence of the amount of AlCl₃ and the temperature on the components of products were also studied in this reaction. Foundation item: Supported by the National Nature Science Foundation of China (No. 29676045) Biography: Wu Lin (1965-), male, Postdictor, research direction: PAHs catalytic conversion and its biologic toxicity.     

Formation of substitutional metallofullerenes by laser ablation of externally doped fullerenes C60M x (M=Sm, Pt, Ni and Rh)

Photofragmentation study of metal fullerides C₆₀M _x (M = Sm, Pt, Ni and Rh) by excimer laser ablation-TOF mass spectrometry shows that metallofullerenes C_2n M and C_2n+1M formed in both the positive and negative ionic modes. The isotopic distributions of the metallofullerenes C_2n M and C_2n+1M are consistent with the calculated spectra based on the natural abundance of isotopes of C and M, confirming the formation of metallofullerenes. The metal atom is supposed to be incorporated into the network of the fullerene cage to replace one carbon atom of the cage forming substitutional metallofullerene. Odd-numbered high carbon clusters are observed in our laser ablation study of all the metal fullerides in the negative ion channel. Evolution of mass spectrum with irradiation laser shots shows that the formation of the substitutionally doped fullerenes is closely related to the production of metal carbide (MC). The structures, as well as formation mechanism, of metallofullerenes C_2n+1M and C_2n M with even and odd numbers of total atoms respectively are discussed based on the structural optimization of the odd-numbered high carbon clusters.     

Temporal-spatial characteristics of vegetation cover and desertification of China by using remote sensing data

Based on the NOAA advanced very high resolution radiometer (NOAA-AVHRR) remote sensing data of 1982 — 1999. the normalized difference vegetation index (NDVI) reflecting the surface vegetation cover has been obtained. Using the empirical orthogonal function analysis, the temporal-spatial eigenvectors of NDVI are given, and the characteristics of the spatial distribution of vegetation cover and its temporal variation together with the desertification of China are analyzed. It is found that the surface vegetation cover has seriously deteriorated in most part of China since 1995. along with the intensified desertification. All these are mainly caused by human activities although the climate change is responsible for the damage of surface vegetation cover to some extent.     

Preliminary study on land surface characteristics over Huaihe River Basin

The analysis of the flux observation dada from the Huaihe River Basin Experiment (HUBEX) shows that, in semi-humid monsoon regions, latent heat flux is as important as sensible heat flux in most situations. Moreover, it can even dominate the sensible heat flux in cropland and paddy field. This is distinct from that for arid and semi-arid regions where the sensible heat flux is dominant. Under clear sky conditions, the soil temperatures in different vertical layers all exhibit certain diurnal variations, and the magnitude decreases with depth to less than 1°C at a depth of 60 cm. This depth is considered as the transition layer for the soil moisture variation. On the other hand, the vertical profile of soil water content varies with the soil texture and even weather conditions, and the layer with maximum soil water content can also be found in Jiangji station during June 1998.     

Hydrogen Production with High Evolution Rate and High Yield by Immobilized Cells of Hydrogen-producing Bacteria Strain B49 in a Column Reactor

To improve the hydrogen evolution rate in continuous hydrogen production of a novel fermentative hydrogen-producing bacteria strain B49 (AF481148 in EMBL), 4 % immobilized cells by polyvinyl alcohol-boric acid method, with the addition of a small amount of calcium alginate in a column reactor obtain hydrogen yield of 2.31 mol H2/mol glucose and hydrogen evolution rate of 1435.4 ml/L culture*h respectively at medium retention time of 2.0 h with a medium containing 10g glucose/L. Moreover, as the cell density in gel beads is increased to 8%, hydrogen yield and hydrogen evolution rate for 10g glucose/L are 2.34 mol H2/mol glucose and 2912.4 ml/L culture*h respectively at medium retention time of 1.0 h, and for molasses wastewater COD of 7505.9 mg/L hydrogen production potential of 205.6 ml/g COD and hydrogen evolution rate of 2057.7 ml/L culture*h at hydraulic retention time of 0.75 h are observed. In the continuous culture pH value keeps around 3.9 by self-regulating.     

准分子激光微细加工

准分子激光对无机和有机材料都有着很好的消融和蚀刻性能 .本文主要描述了准分子激光消融和蚀刻在微细加工方面的应用     

被子植物无融合生殖种质资源研究

已发现 3 6个科 440多个种的被子植物具有无融合生殖特性 ,包括无孢子生殖、二倍体孢子生殖和不定胚生殖 其中 1 0个科有无孢子生殖特性 ,1 0个科具二倍体孢子生殖特性 ,2 2个科具不定胚生殖特性 ,4个科兼具二倍体孢子生殖和无孢子生殖特性 ,1个科兼具无孢子生殖、二倍体孢子生殖和不定胚生殖三种生殖特性 ,1个科有不定胚和无孢子生殖特性 双子叶植物至少 2 8个科有无融合生殖特性 ;单子叶植物至少 5个科具有无融合生殖特性 ,其中禾本科植物 49个属 1 70多个种能进行二倍体孢子生殖或无孢子生殖