ICP-AES法测定钢中的铈

建立了离子体发射光谱仪测定钢中铈元素的方法。为消除共存元素对铈分析游线的光谱干扰,选择Ce413．380nm作为分析线,铈含量在0．005％-0．50％之间工作曲线线性良好。对于含量范围在0．005％-0．10％的铈元素,回收率为85．6％-12．5％,测定结果的相对标准偏差小于9．74％（n=8）;对于含量范围在0．10％-0．50％的铈元素,回收率为99．5％-103．0％,测定结果的相对标准偏差小于3．52％（n=8）。该方法适宜钢中含量范围在O．005％-0．50％的铈元素的测定。     

高效液相色谱法与酶联免疫试剂盒测定海水中痕量氯霉素

详细报道了海水样品中氯霉素的高效液相色谱检测方法及酶联免疫试剂盒检测方法。应用高效液相色谱法测定海水中氯霉素,方法的线性范围为5～50ng,检出限为0．064ng,回收率为96．2％-118．4％,相对标准偏差小于8．9％。酶联免疫试剂盒测定海水中的氯霉素背景值偏高,在加标浓度为10ng／mL时回收率为101．0％,相对标准偏差为8．32％。     

固相萃取-梯度洗脱高效液相色谱法同时检测饲料中十三种磺胺类药物

建立了一种同时检测饲料中十三种磺胺类药物含量的方法,样品用磷酸盐缓冲液提取,HLB固相萃取小柱净化,梯度洗脱-HPLC分析,方法定量下限为0．5mg／kg,在0．5～10．0mg／kg添加水平上的回收率为63．6％～118．2％,相对标准偏差4．78％～17．24％,方法简便．适用于饲料中低含量磺胺类药物检测．     

微波消解平台石墨炉原子吸收法测定活性污泥中的铜和铅

建立了一种微波消解样品,平台石墨炉原子吸收法测定活性污泥中Cu、Pb含量的方法,该方法的样品加标回收率Cu为95．6％～98．3％,Pb为92．3％～97．0％,相对标准偏差RSD（%）：Cu为1．0％～2．0％,Pb为2．0％～2．9％,检验限Cu为0．0052ng／g,Pb为0．0073ng／g,该方法应用于活性污泥中Cu,Pb的分析,实验所需时间短,取样量少,空白值低,实验过程中样品损失少,准确度和灵敏度高,结果令人满意．     

氢化物发生-原子荧光光谱法自动进样快速测定烟道灰中硒的应用研究

应用常规湿法消解与微波高压溶样2种不同的样品分解方法,研究了氢化物发生。原子荧光光谱法（HGAFS）测定烟道灰中的硒．硒标准系列浓度在0．000～0．024mg／L范围内与荧光强度具有良好的线性关系,相关系数为0．9998。方法检出限为0．0075mg／kg,相对标准偏差在0．87％～1．30％之间,加标回收率为98％～105％,实验证实方法具备灵敏、快速、准确等优点．亦为回收利用烟道灰中的硒提供了科学依据。     

茶叶中9种有机磷农药残留量快速测定方法

为建立了茶叶中9种有机磷农药的气相色谱检测方法,将试样在气相色谱仪DB—XLB色谱柱中分离,FPD检测器鉴定。结果表明,9种有机磷能够很好地分离,在0．05～1．0灿∥mL线性关系良好（r≥0．999）。在0．05—0．20mg／kg的添加水平范围内的平均回收率为78．6％～105％,相对标准偏差为1．4％～7．8％。9种有机磷方法检出限0．005～0．01mg／kg。     

气相色谱法分离和测定环境空气中的丙烯酸乙酯和甲基丙烯酸甲酯

用活性炭吸附环境空气中的丙烯酸乙酯和甲基丙烯酸甲酯,经二硫化碳妥吸后用气相色谱法测定在填充２．５％ＤＮＰ＋２．５％Ｂｅｎｔｏｎｅ３４／ＣｈｒｏｍｏｓｏｒｂＷ ＨＰ ＤＭＣＳ的玻璃色谱柱上,丙烯酸乙酯与甲基丙烯酸甲酯及干扰物之间能较好地分离。方法的回收率：丙烯酸乙酯为８６．４％－１０３．０％,甲基丙烯酸甲酯为８６．３％－１０１．２％,变异系数：丙烯酸乙酯为４．１％－４．４％,甲基丙烯酸甲酯为４．４％     

气相色谱法测定羟乙基乙二胺中的乙二胺含量

采用毛细管气相色谱内标法测定羟乙基乙二胺中的乙二胺含量．结果表明。乙二胺在0．12．0ms／mL范围内的线性关系良好（r=0．9997）,检出限为0．02m/mL,方法的精密度RSD为1．7％（n=6）,加标回收率在95％～101％．     

热解齐化-原子吸收光谱法测定红土镍矿中汞含量

经过条件试验,建立了热解齐化-原子吸收光谱法直接测定红土镍矿中汞含量的方法。样品中汞含量在57～1752μg／kg,重复测定的相对标准偏差（RSD）在1．6％～5．3％（n=11）,回收率在92．79％～94．77％,与冷原子吸收光谱法的方法间相对偏差为5．18％～11．93％。方法准确、快速、样品用量少、无试剂污染,适合于批量样品的测试,有应用和推广价值。     

梨果及土壤中亚胺唑及其代谢物的气相色谱分析

 介绍了杀菌剂亚胺唑及其代谢物ＩＢＣ－０１在梨果实及土壤样品内的提取、净化方法以及气相色谱的分析测定方法。保留时间：亚胺唑为３８．３６ｍｉｎ，ＩＢＣ－０１为１７．０１ｍｉｎ。变异系数：亚胺唑为０．４５％～１５．５３％，ＩＢＣ－０１为３．０３％～９．５２％。回收率：亚胺唑为８８．２８％～９８．５％，ＩＢＣ－０１为８４．９８％～９８．１３％。     

Robust curve fitting method for optical spectra by least median squares (LMedS) estimator with particle swarm optimization (PSO).

A curve fitting technique for optical spectra based on a robust estimator, least median squares (LMedS), is introduced in this study. For the effective calculation of LMedS, particle swarm optimization (PSO) is also introduced. Unlike a standard curve fitting method using least squares (LS) estimator, the method based on LMedS estimator is less influenced by outliers in experimental data. Two kinds of data sets, simulated data with outliers and temperature-dependent near-infrared (NIR) spectra of oleic acid (OA) are applied for the demonstration of the proposed method. The results clearly reveal that, compared with the LS estimator, the proposed method can effectively reduce undesirable effects of low SN ratio and can yield more accurate fitting results.     

Analysis of Block and Statistical Copolymers by Gel Permeation Chromatography: Estimation of Mark-Houwink Constants

Abstract

A method is introduced for the estimation of Mark-Houwink constants of block and statistical copolymers. The homopolymer Mark-Houwink constants and copolymer composition are required. Use of estimated Mark-Houwink constants in GPC analyses gives results which agree well with those calculated with experimentally determined constants. Comparisons between this method and those of Runyon and coworkers (11) and Chang (12) are made for block copolymers. Chang's method was also extended to statistical copolymers, and where it compared closely with the one introduced here. The use of copolymer Mark-Houwink constants as a qualitative measure of polymer compatibilities in different solvents is also discussed.     

3,5-二硝基水杨酸比色法在烷基多苷体系中的应用研究

将3,5-二硝基水杨酸比色定糖法(DNS法)引入烷基多苷体系中,研究了丁苷化过程中葡萄糖含量随时间的变化,表征了丁苷化反应产率,测定了烷基多苷产品中残留的葡萄糖含量,并将测定结果与传统方法进行了比较,结果表明该法是一种简便快速、准确度高的方法。     

耐高温高表面氧化铝的制备及性质──添加钡及钡与镧的协同作用对氧化铝热稳定性的影响

氧化铝是高温催化反应中常用的载体材料. 高于1 000 ℃时, Al2O3通过表面活性原子的迁移和表面羟基脱水发生烧结, 并向α相转变[1,2], 同时随着比表面积剧烈下降, 导致催化剂活性组分聚集, 催化剂活性下降等. 大量研究表明, 稀土元素, 硅及碱土元素可明显改善氧化铝的热稳定性[3～8]. 本文以溶胶-凝胶法单独引入Ba元素, 考察了Ba添加量对Al2O3热稳定性的影响. 还采用溶胶-凝胶与表面浸渍相结合的方式共同引入La和Ba, 考察了两元素协同作用对Al2O3热稳定性的影响.     

无定形碳的逆向蒙特卡洛法建模

作为一种很有前景的建模方法,逆向蒙特卡洛法（Reverse Monte Carlo 简称RMC 法）在无定形碳结构研究中得到了广泛应用。本文阐述了RMC 法对于无定形碳材料结构识别的意义,简介了该法的基本原理,同时针对使用RMC 法建立无定形碳结构模型时遇到的两大难点：即模拟结构的真实性问题和大尺寸孔网络的建模问题,综述了该方法的改进和发展趋势。几何约束和能量约束的使用,提高了模拟结构的真实性;具有介孔的多孔碳模型的建立,将成为今后研究的热点。     

On using the adjacency matrix power method for perception of symmetry and for isomorphism testing of highly intricate graphs

A modification of the adjacency matrix power method described recently for the perception of symmetry in graphs is introduced, which expands the limits of the method far beyond the realm of chemically interesting graphs. The procedure finds the automorphism partition even for intricate graphs without performing a tree search. The calculation effort increases with the problem size polynomially for all tested cases, including strongly regular graphs, two-level regular graphs, and graphs corresponding to balanced incomplete block designs (BIBD). An equally powerful computer program for testing isomorphism of graphs based on the adjacency matrix power method is introduced.     

季铵碱的合成研究进展

简要综述了季铵碱的5种合成方法,包括氧化银法、碱置换法、离子交换树脂法、双极膜电渗析法和电解法（电膜反应器法）。对比分析了各种合成方法的优势与局限性,并对其未来的发展前景进行了展望。     

In situ and online monitoring of hydrodynamic flow profiles in microfluidic channels based upon microelectrochemistry: concept, theory, and validation.

Herein, we propose a method for reconstructing any plausible macroscopic hydrodynamic flow profile occurring locally within a rectangular microfluidic channel. The method is based on experimental currents measured at single or double microband electrodes embedded in one channel wall. A perfectly adequate quasiconformal mapping of spatial coordinates introduced in our previous work [Electrochem. Commun. 2004, 6, 1123] and an exponentially expanding time grid, initially proposed [J. Electroanal. Chem. 2003, 557, 75] in conjunction with the solution of the corresponding variational problem approached by the Ritz method are used for the numerical reconstruction of flow profiles. Herein, the concept of the method is presented and developed theoretically and its validity is tested on the basis of the use of pseudoexperimental currents emulated by simulation of the diffusion-convection problem in a channel flow cell, to which a random Gaussian current noise is added. The flow profiles reconstructed by our method compare successfully with those introduced a priori into the simulations, even when these include significant distortions compared with either classical Poiseuille or electro-osmotic flows.     

Direct Determination of Potassium in Human Blood Serum by Flow Injection Flame Photometry with Automatic Dilution

Abstract

A method was developed for the automatic quantitative determination of potassium in serum, by flow injection analysis. The serum sample is directly introduced in the flow. The dilution with deionized water stream is done automatically and sequentially in the system to reach the adequate concentration to be introduced in the flame photometer. The results achieved with this method, for serum samples obtained in the Hospital of the University, had been compared with those values of the Hospital laboratory that uses manual dilution and flame photometry. The results obtained by the two methods agree within at least ±5%. About 60 samples/hour can be easily analyzed by the method proposed in this work.     

小体积外循环进样ICP-AES直接测定薄膜样品成份

本文试用小体积外循环进样系统,不称样重、不计试液体积,用归一计算法(或摩尔比法)ICP-AES直接进行小试样样品的成份测定,方法简便、快速,分析结果满意。