等速电泳-高效液相色谱联用分离复杂样品的研究

将ＯＣＥＰ－１型等速电泳仪和Ｗａｔｅｒｓ高效液相色谱仪主要部件联用,配以自制的接口,建立高效液相色谱－等速电泳新联用系统,成功地研究了含蛋白质和一些金属离子的复杂样品的分离分析。     

Electrochemical Study of 4-Nitrophenol at a Modified Carbon Paste Electrode

 A zeolite-modified carbon paste electrode (CPE) has been used for the determination of 4-nitrophenol by differential pulse voltammetry (DPV). The electrochemical reduction of 4-nitrophenol at −1.0 V is carried out in a Britton-Robinson medium at pH 3.5. The cyclic voltammetric (CV) behaviour has been investigated to study the nature of the process. Studies on the effect of pH were carried out over the pH range 2–9 with the Britton-Robinson buffer solution, and the influence of pH on peak height and peak potential was analyzed. A linear relationship between peak intensity and concentration is obtained in the range 0.2–10 mg L⁻¹, with a detection limit of 0.04 mg L⁻¹; a relative standard deviation of 1.5% for a 5 mg L⁻¹ 4-nitrophenol concentration and a relative error of 2.6% were also obtained (n=11). Received March 3, 1998. Revision December 10, 1998.     

表面活性剂-磺基水扬酸对镱原子吸收光谱的高增敏作用研究

本文就表面活性剂-磺基水杨酸对镱在乙炔-空气火焰中的高增敏作用进行了研究,结果表明,在十二烷基硫酸钠(SDS)与磺基水杨酸(SSA)共存时。镱的灵敏度增高50倍,其它稀土元素和一些阴离子对Yb的干扰得到了有效的抑制,对硫酸根和磷酸根尤其明显,同时也研究了该体系的增敏机理。在Yb-SDS-SSA体系中,镱的检出限为0.031μg/mL,在0.050～2.0μg/mL镱的浓度范围内,其相对标准偏差为3.0％。     

THE DONNACHIE-LANDSHOFF MODEL WITH A NON-LINEAR TRAJECTORY AND THE COLLIDER DATA

It is pointed out that the Donnachie-Landshoff model does not agree with the collider b-data. A non-linear pomeron trajectory is introduced in the model to remedy this defect.     

Extrapolation Combined with Multigrid Method for Solving Finite Element Equations

An algorithm combining the MG method with two types of extrapolation is given for solving finite element equations with any initial triangulation. A high order approximation to the solution of PDEs can be obtained at the cost of order O(N) of computational work.     

镍氮掺杂有序大孔/介孔碳负载银纳米颗粒用于高效电催化CO2还原

多组分体系中的协同作用为设计高效的二氧化碳还原电催化剂提供了新的思路. 本工作通过双模板法和化学还原法精心设计制备了大孔/介孔镍氮掺杂碳(Ni-N-OMMC)负载银纳米颗粒复合材料(Ag/Ni-N-OMMC), 用于高效电催化还原CO₂为CO. 此复合材料表现出良好的电催化活性, 在CO₂饱和的0.1 mol•L^–1 KHCO₃电解液中, 电位为–1.0 V (相对于可逆氢电极, RHE)时CO的电流密度(J_CO)高达33.29 mA•cm^–2. 并具有较宽的工作电压范围, 在–0.7~–1.0 V (vs. RHE)下, CO的法拉第效率超过90%. 其优异的电催化性能可能归因于Ag纳米颗粒与具有丰富Ni-N _x活性位点的Ni-N-OMMC载体之间的协同效应, 以及三维互联有序大孔/介孔结构提供的高比表面积和高效的质量/电荷传输.     

化学美育对智育和德育的促进作用

报载钱学森呼吁:“要重视学生右脑的开发,加强形象思维训练”。而传统的化学教学,人们比较重视基础知识的传授和基本技能的训练,即重视人脑的左半球-一逻辑思维、语言、计算的半球的开发和利用,忽视具有创造性和形象思维专长的人脑右半球的开发和利用。化学教学中的美育,开发的正是学生的右脑。     

Search for 10TeV Gamma-Ray Bursts

A search for gamma-ray bursts at 1OTeV energy region was made using data of Yangbajing air shower experiment in Tibet.About 4×10⁸ events were analysed to search for shower clusters appearing in a given time interval and a given small sky bin. An equal-zenith angle method is adopted to estimate the background. Some clusters show excesses over the background but with less significance as the evidence of gamma-ray bursts.The much higher sensitivity of the Yangbajing second phase array to the detection of 1OTeV gamma-ray bursts is discussed.     

Properties of the States Generated by the Excitations on a q-Coherent State

We study the mathematical and physical properties of the states which are generated by excitation on a q-analogue of the coherent state. With the help of a q-analogue of the Laguerre polynomial, the squeezing and the statistical properties of the field in such the state are also discussed.     

磁性隧道结Ni80Fe20/Al2O3/Co的制备和物性

用等离子体氧化形成绝缘层的方法,重复性地制备出了Ｎｉ８０Ｆｅ２０／Ａｌ２Ｏ３／Ｃｏ磁性隧道结。样品的隧道磁电阻（ＴＭＲ）比值在室温下最高可达６．０％,翻转场（ｓｗｉｔｃｈ ｆｉｅｌｄ）可低于８００Ａ／ｍ,平台宽度约２４００Ａ／ｍ。结电阻的变化范围从几百欧姆到几百千欧。