粮谷和油籽中丰索磷残留量的气相色谱及气相色谱／质谱分析

介绍应用气相色谱和气相色谱－质谱法测定及确证粮谷和油籽中丰索磷的残留含量，试样采用水－丙酮提取，提取液经液－液分配后，再以弗罗里硅土柱净化，气相色谱，火焰光度检测器测定，外标法定量，并用气相色谱－质谱针对丰索磷的选择监测离子的种类和丰度比进行敢阳性确证。     

POLYMERIZATION OF OCTAFLUOROCYCLOBUTANE IN GLOW DISCHARGE Ⅱ. ESCA AND IR CHARACTERIZATION OF POLYMER STRUCTURE*

In a capacitively coupled discharge with external electrodes, He, H_2, N_2 or Ar were used as plasmagas, polymerization of octafluorocyclobutane was carried out under different conditions by varyingdischarge power, pressure, plasma gas and plasma-gas/monomer ratio. Structure of polymerizedproducts was characterized by IR spectroscopy and ESCA measurement. It was found that therewere six elements in the products, i.e. C, F, Si, O, N and H. The probably existed groups in poly-mers wer investigated. By analyzing the resolved peaks of C_(1S) region in ESCA spectra, effect of thereaction conditions on degree of branching of the polymerized products and the relationship of thepolymer structure wth the mechanism of the competitive ablation and polymerization process werestudied. In addition, polymer deposition process occurring in glow discharge was discussed.     

聚苯胺尿酸酶电极性能的研究

依据pH对聚苯胺尿酸酶电极最大响应电流的影响, logim～pH图表明尿酸酶电极的催化活性只与其电离基团的碱性形式有关. 扫描电镜的结果表明, 聚苯胺尿酸酶电极的稳定性与其制备方法有关. 电化学法固定的尿酸酶电极具有高的稳定性.     

稀土萘乙酸邻菲绕啉三元配合物的合成和表征

合成了6种稀土(RE)-萘乙酸(NAA)-邻菲绕啉(Phen)固体配合物,其通式为RE(NAA)_3·Phen(RE=Y,La,Nd,Sm,Eu,Er)。通过元素分析,摩尔电导,IR,UV-Vis,H-NMR,XPS和TG-DTA分析,研究了配合物组成、性质及稀土离子与配体间的成键特性。     

葡萄糖衍生的新型光学活性β－氨基醇的合成

首次报道了以Ｄ－葡萄糖为原料合成新型光学活性葡萄糖衍生类β－氨基醇化合物的新方法。目标化合物：（２Ｓ，３Ｓ）－甲基－２－脱氧－２－苯胺基－４，６－ｏ－苄叉基－α－Ｄ－吡喃阿卓糖苷（７）经各种分析测试手段证实。     

活性碳分离碳－60和碳－70

活性碳用苯胺处理后，可以减少对Ｃ＿（６０）和Ｃ＿（７０）的不可逆吸附，从而增加Ｃ＿（６０）和Ｃ＿（７０）的分离收率，同时提高了Ｃ＿（７０）的纯度。     

镧对Rhizoctonia solani的毒力及其致病酶活性的影响

采用琼脂平板生长速率法及液体培养基培养测定了La对立枯丝核病菌(Rhizoctoniasolani)的抑制作用和毒力,并测定了其对病菌胞外的果胶酶、蛋白酶和纤维素酶等几种致病酶的活性的影响。结果表明,随着La浓度升高,对病菌菌丝生长的抑制作用增强,固体培养上所测定的对病菌的EC50和EC95分别为171.9和667.7mg·L-1;在液体培养基中所测定的EC50和EC95分别为111 4和500 7mg·L-1。在一定浓度范围内,La提高了单位量菌丝所产生3种致病酶的活性,但由于对菌丝生长量的强烈抑制,使病菌胞外3种致病酶的总量或总活性受到抑制,减低了病菌的致病力。     

An Investigation of Inclusion Complexes of Cyclodextrins with Phenylurea Herbicides by Photochemically-Induced Fluorescence. Analytical Applications

The effect of -cyclodextrin (-CD) and hydroxypropyl--cyclodextrin (HP--CD) upon the photochemically-induced fluorescence (PIF) properties of four phenylurea herbicides, including linuron, diuron, isoproturon and neburon has been studied. Photochemical conversion of these nonfluorescent herbicides into strongly fluorescent photoproducts was shown to occur in -CD and HP--CD aqueous media. The influence of pH, UV irradiation time and photoproduct stability on the fluorescence intensity was also investigated. In addition, the stoichiometry and formation constants of the complexes formed between herbicides and -cyclodextrin (-CD) or 2-hydroxypropyl--cyclodextrin (HP--CD) were determined. The formation constant values, ranging from 184 ± 40 to 1498 ± 245 M^-1, were calculated by applying the iterative nonlinear regression (NLR) approach to the PIF data. Linear calibrations graphs were established in the interval 1–12 g/mL, for diuron, linuron and neburon. The IUPAC limits of detection ranged between 580 and 700 ng/mL, according to the compound. Application to the analysis of phenylurea herbicides in spiked river water was also described.     

Control of the Properties of Carbon Nanotubes Synthesized by CVD for Application in Electrochemical Biosensors

Interest in carbon nanotubes (CNT) has grown at a very rapid rate in the last decade. Their interesting physical and chemical properties open attractive possibilities in many application areas. These properties depend on the process conditions during synthesis and on subsequent purification steps. Recent studies have demonstrated that CNT can promote the electron transfer of biomolecules. These exceptional properties make them attractive for use in electrochemical biosensors. Multi walled nanotubes have been synthesized by the Chemical Vapor Deposition (CVD) method using methane as a carbon source and Ni–Al₂O₃–SiO₂ as the catalyst. The influence of the variation of certain reaction parameters such as feed gas composition, catalyst mass, temperature and reaction time in the yield of the CVD process has been established. In addition, the structural and chemical characteristics of the CNTs have been studied and a purification process to eliminate the catalyst and amorphous carbon has been developed that involves a gaseous oxidative process and acid treatment. The efficiency of the purification step has been determined by analytical techniques. Atomic force microscopy, Raman scattering, thermogravimetric analysis, inductively coupled plasma atomic spectroscopy are the characterization techniques employed in this work.     

用原子捕获技术提高火焰原子吸收光谱法的灵敏度

采用简易的石英原子捕获器，使Ｃｕ，Ａｇ，Ａｕ，Ｚｎ，Ｃｄ，Ｐｂ，Ｓｂ，Ｂｉ等易挥发元素在空气－乙炔火焰原子吸收光谱法中的灵敏度提高了３～５倍，并有较好的精密度，相对标准偏差在１％左右，方法中用此技术测定了标准物质中Ｐｂ、Ｃｄ的含量，获得了满意的结果，它较之石墨炉原子吸收光地具有快速，简便的特点，具有较大的实用价值。