吸附溶出伏安法同时测定水中痕量锌和镉

报道了同时测定痕量锌和镉的新方法 .在 0 .0 1mol/LHAc - 0 .0 1mol/LNaAc- 1.2× 10 - 5mol/L乙醛酸缩氨基硫脲 (GATSC)中 ,Zn -GATSC和Cd -GATSC均产生非常灵敏的吸附波 ,峰电位分别是 - 0 .82V和 - 0 .4 3V(vs·SCE) ,峰电流和锌、镉的浓度分别在 3.0× 10 - 8～ 8.0× 10 - 7mol/L和 1.0× 10 - 8～ 6 .0× 10 - 7mol/L范围内成直线关系 ,检测限分别是 8.0× 10 - 9和 3.0× 10 - 9mol/L .该方法用于测定水中痕量锌和镉 ,结果令人满意     

方波溶出伏安法同时测定废水中微量的锌、镉、铅和铜

报道了用方波溶出伏安法同时测定废水中微量锌、镉、铅和铜的一种方法.在浓度为0.15mol/L,pH=5.0的氯化铵分散体系中,温度18℃的条件下,Zn2 、Cd2 、Pb2 和Cu2 均灵敏地产生溶出峰,峰位分别为:-1.13V、-0.72V、-0.50V、-0.22V(vs,S.C.E).线性范围分别为2×10-7～2×10-5、2×10-7～2×10-5、1×10-7～2×10-5和5×10-7～5×10-5mol/L,检测限为2×10-8～2×10-7mol/L,回收率为87.7～102.4%.     

碳纳米管修饰碳糊电极同时测定铜和铅

制备了碳纳米管化学修饰碳糊电极,采用循环伏安法,在pH为4·20的B-R缓冲溶液中同时对Cu2+和Pb2+进行测定.结果表明,Cu2+和Pb2+浓度分别在3·0×10-6～1·0×10-4mol/L和6·0×10-6～1·0×10-4mol/L范围内呈良好的线性关系,检出限分别为5·6×10-8mol/L和1·8×10-7mol/L,线性相关系数R分别为0·9884和0·9909.     

线性扫描极谱法连续测定红菇中的铜、镉、锌

在0.4mol·L-1 NH3·H2O-NH4Cl缓冲溶液中(pH=9.19),用线性扫描极谱法连续测定了红菇中Cu、Cd、Zn三种微量元素的含量.研究结果表明:Cu2 、Cd2 、Zn2 的峰电位分别为-0.45V(vs·SCE)、-0.79V(vs·SCE)、-1.33V(vs·SCE);线性范围分别为1.3×10-5～1.5×10-4 mol·L-1、2.5×10-5～5.0×10-4mol·L-1、2.5×10-5～5.0×10-4mol·L-1;检出限分别为0.006μg/mL、0.005μg/mL、0.006μg/mL,回收率分别为97.0～100.5%、98.4～102.0%、96.5～102.6%.此方法准确、简便、快速、灵敏度高.     

蛋白质的电化学特性研究

研究了蛋白质的极谱特性 .在 p H值为 2 .6 6的 B- R缓冲溶液中 ,当有 0 .0 70 mol/ L KCl存在时 ,BSA在 - 1.90 V左右产生一良好的极谱波 ,利用此波可测定微量的 BSA,线性范围为 4 .5× 10 - 8～ 2 .0× 10 - 6mol/ L,检测下限为 2 .7× 10 - 8mol/ L.所提出的方法不经任何预处理可直接测定血清中的蛋白质 .     

玻碳电极吸附伏安法测定痕量钴的研究

报道了采用玻碳电极测定钴的吸附伏安法 .通过在含 2 - (5 溴 2 吡啶偶氮 ) - 5 -二乙氨基苯酚 (5 Br PADAP)的 0 12mol/LNaOH溶液中于 - 0 5 0V富集时 ,钴 (Ⅱ )与配体 5 Br PADAP生成的络合物吸附于电极表面 ,然后进行阴极极化扫描 ,于 - 0 85V左右获得一灵敏的溶出峰 ,二次导数峰电流与钴 (Ⅱ )浓度在 5 0× 10 - 10 ～ 1 0× 10 - 7mol/L范围内呈线性关系 ,检出限达 2× 10 - 10 mol/L .同时 ,对电极反应机理进行了探讨 .方法应用于测定VB12 注射液中的钴 ,结果满意     

痕量间苯二酚的B-Z振荡反应动力学测定

研究了在封闭体系中B Z振荡反应测定间苯二酚的条件 ,建立了测定痕量间苯二酚的新方法 .当 [KBrO3]=0 2 5mol/L ,[CH2 (COOH) 2 ]=0 5mol/L ,[Ce(SO4 ) 2 ]=0 0 4mol/L ,[H2 SO4 ]=0 8mol/L时 ,间苯二酚在 6 5×10 - 7mol/L～ 1 0× 10 - 5mol/L范围内 ,浓度与振幅改变值ΔA呈线性关系 ,检出限为 6 0× 10 - 7mol/L .用于废水中间苯二酚的测定 ,回收率为 99% .     

Zn(II)-Morin配位吸附波的研究及应用

以桑色素(Morin)为配位体,研究了Zn(II)与其形成的配合物在汞电极上的极谱行为和极谱波的性质,确定了Zn(II)-Morin配合物的组成。在pH=4.7的0.1 mol.L-1HAc-NaAc底液中,Zn(II)-Morin配合物在2.0次微分极谱图上产生良好的吸附还原波。其峰电位为-1.14 V,峰电流与Zn2 在7.5×10-8~4.3×10-6mol.L-1的浓度范围内呈线性关系,最低检出限为7.5×10-8mol.L-1。用于实际样品测定,结果令人满意。     

玻碳电极吸附循环伏安法测定维生素B_2

目的 :研究维生素B2 在玻碳电极表面吸附的电化学行为及定量分析方法 .方法 :玻碳电极在 8.0mol/LHNO3 介质中 ,于 + 0 .6～ + 2 .0V (vs.SCE)的电位范围内进行循环扫描电活化后 ,维生素B2 在电极表面具有很强的吸附性 ,在底液为 0 .0 5mol/L柠檬酸 + 0 .1mol/LNa2 HPO4 (pH =4 .9)的介质中 ,吸附电位 - 0 .3V ,在 0～ - 0 .7V的范围内 ,以 90mV/s的速度进行循环伏安扫描 .结果 :实验表明VB2 在电极表面具有可逆吸附波的特征 ,VB2 浓度与峰电流在 6.0× 10 - 8～ 7.0× 10 - 6 mol/L之间成线性关系 ,检测限为 1.0× 10 - 8mol/L .结论 :建立了维生素B2 在玻碳电极表面的电化学分析方法 ,将该法运用于实际样品药片中VB2 含量的测定 ,获得满意的结果 .     

谷胱甘肽自组装膜修饰电极用于Cr(VI)离子的测定

将谷胱甘肽(GSH)自组装膜修饰电极用于Cr(Ⅵ)的测定.实验表明,在0 02mol/LH2SO4 0 1mol/LNaNO3溶液中,在 1 00～-0 40V电位范围内进行循环伏安扫描,于 0 29V(Vs.SCE)处获得铬的还原峰信号、 0 65V(Vs,SCE)处获得铬的氧化峰信号.Cr(VI)在GSH/Au修饰电极上的电化学行为比裸金电极有明显的改善,峰电流更为灵敏,且还原峰电流随着Cr(VI)浓度的增加而增大,因此选择 0 29V的还原峰作为分析信号,运用1 5次微分线性扫描伏安法对铬进行了定量分析,线性范围为1 0×10-8～1 0×10-6mol/L,检测限为1 0×10-9mol/L.将所建立的方法应用于湖水样品中铬含量的测定,以ICP进行对照实验,结果满意.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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