悬汞电极静止电位溶出分析法研究

假定静止溶出过程受氧化剂在电极表面的极限流量控制,在静止30s以上的条件下,本文推导出悬汞电极静止电位溶出分析法理论公式,理论计算与实验结果基本相符。     

超微盘电极上电位溶出分析法理论

本文提出了超微盘电极上电位溶出分析法理论,内容包括:过渡时间(τ)方程式、电位(E)-时间(t)曲线方程式及微分电位溶出分析法dt/dE-E曲线方程式,并对该曲线的性质进行了论述。     

悬汞电极电位溶出分析法研究

电位溶出分析法近年来有迅速的发展和广泛的应用,八十年代初开始的该法理论研究的进展不仅定量解释了实验事实,而且开拓了该法应用的新领域,本文报告悬汞电极电位溶出分析法的理论研究结果。     

平面汞膜电极二阶倒导数电位溶出分析法研究

对电位溶出的Ｅ－ｔ曲线进行二阶倒导数处理，提高了二阶倒导数电位溶出分析法理论，其信号较一阶倒导数法增强约４３．１ｎ倍，分辨率由原来的６５．５ｍＶ／ｎ改善到４８．２ｍＶ／ｎ。用根据二阶倒导数法原理自行设计研制的多阶倒导数电位出仪验证了本提出了的理论，富集１２０ｓ，Ｃｄ＾２＋的检测限可达１．０×１０＾－１０ｍｏｌ／Ｌ。     

电位溶出分析法述评

自1976年D. Jagner提出电位溶出分析法以来,此法发展迅速,日益受到人们的重视,已成为电分析法的一个重要分支。本文将根据近几年国内外文献,对本法在某些基础理论研究方面的进展及其在各领域中的分析应用加以评述。     

电位溶出分析法的理论和验证

本文推导了电位溶出分析法的过渡时间和电位-时间曲线方程式,并成功地进行了验证,理论和实验结果十分符合。     

低信膜比条件下金膜电极电位溶出分析法研究

推导并验证了信号与金膜厚度的比值较小（即低信膜比）时金膜电极电位溶出分析法的过渡时间方程式和电位时间方程式。实验确定的理论式的应用条件为τ／ｌ２≤５８×１０１０ｓ／ｃｍ２，并发现当扩散路径约为扩散层厚度的３倍时，便可按半无限扩散条件处理扩散问题。从而解决了利用小信号进行金膜电极电位溶出基本问题，即信号与浓度的定量关系。     

微分电位溶出仪及其性能测试

自Jagner 1976年提出电位溶出分析以来,出现了许多各具特色的仪器。Anderson等于1982年提出用ISS820电位溶出分析仪配用微处理机,使PSA灵敏度大大提高,1981年,Christensen等提出微分电位溶出分析(DPSA)。1983年,Alex Hu等用微处理机配用多道分析仪亦实现了DPSA。但关于微分电位溶出分析峰高与浓度关系未见报导。国内在81年仅有6篇关于PSA的文献。其中包括作者一篇。所用仪器全系常规PSA,为了适应我室     

化学修饰电极电位溶出法的研究 Ⅱ.聚乙烯吡啶化学修饰电极还原电位溶出法测定蔬菜、水果中维生素C

本文提出PVPCME还原电位溶出分析法,研究了工作电极的修饰和制备过程,电极重复性好,灵敏度高。讨论了测定蔬菜、水果中维生素C的实验条件。方法的变异系数为1.47％,回收率为88～91％。样品处理简单,损失小。     

间断多次扫描电位溶出分析方法的研究

间断多次扫描电位溶出分析是在多次扫描电位溶出分析和间断扫描伏安法的基础上提出的一种新的电位溶出分析技术,它不仅具有多次扫描电位溶出分析灵敏度高的优点,又克服了多次扫描电位溶出分析对多元素分析时元素之间相互干扰的缺点。文章讨论了间断多次扫描电位溶出分析的实验条件,同时用这种方法分析了人尿中镉、铅的含量。间断多次扫描电位溶出分析在电积10分钟时,最低可检测到0.005ng/mL的镉和0.01ng/mL的铅。镉、铅浓度为4ng/mL时,相对标准偏差分别为2.9%和3.2%,证明间断多次扫描电位溶出分析可以同脉冲阳极溶出伏安法媲美。     

线性扫描伏安法研究(Ⅰ)——微盘电极上准稳态可逆波方程式及其验证

本文报道微盘电极上线性扫描伏安法准稳态可逆波方程式,并成功地进行了验证,理论和实验结果十分符合。     

Estimation of Critical Temperature of Thermal Explosion for Energetic Materials Based on Non-isothermal Kinetic Equation dα/dt =A_0 exp(bT)[1+(T–T_0 )b]f(α)

Critical temperature(T b ) of thermal explosion for energetic materials is estimated from Semenov’s thermal explosion theory and the non-isothermal kinetic equation dα/dt=A 0 exp(bT)[1+(T–T 0 )b]f(α) deduced via reasonable hypotheses, where T 0 is the initial point of the deviation from the baseline of DSC curve. The final formula is (T b –T e0 ){1+1/[1+( T b –T 00 )b]}=1. We can easily obtain the initial temperature(T 0i ) and onset temperature(T ei ) from the non-isothermal DSC curves, the values of T 00 and T e0 from the equation T 0i or ei =T 00 or e0 +α 1 β i +α 2 β i2 +…+α L–2 β iL –2 , i=1,2,…,L, the value of b from the equation: ln[β i /(T ei –T 0i )]=ln[A 0 /G(α)]+bT ei , so as to calculate the value of T b . The result obtained with this method coincides completely with the value of T b obtained by Hu-Yang-Liang-Wu method.     

New approximate formula for the generalized temperature integral

A new procedure to approximate the generalized temperature integral $ \int_{0}^{T} {T^{m} {\text{e}}^{ - E/RT} } {\text{d}}T, $ which frequently occurs in non-isothermal thermal analysis, has been developed. The approximate formula has been proposed for calculation of the integral by using the procedure. New equation for the evaluation of non-isothermal kinetic parameters has been obtained, which can be put in the form: $$ \ln \left[ {{\frac{g(\alpha )}{{T^{(m + 2)0.94733} }}}} \right] = \left[ {\ln {\frac{{A_{0} E}}{\beta R}} - (m + 2)0.18887 - (m + 2)0.94733\ln {\frac{E}{R}}} \right] - (1.00145 + 0.00069m){\frac{E}{RT}} $$ The validity of the new approximation has been tested with the true value of the integral from numerical calculation. Compared with several published approximation, the new one is simple in calculation and retains high accuracy, which indicates it is a good approximation for the evaluation of kinetic parameters from non-isothermal kinetic analysis.     

有限圆盘电极上计时电流方程式

本文报道一个形式简单、结果准确、适用于任何时间的有限圆盘电极上计时电流方程式,结果为i_t=4nFD_RT₀[θ/(1+θ)]C_R^*,f(τ)[式中 ,τ=4D_Rt/r₀²,r₀为电极半径,t为时间,0=expnF(E-E⁰)/RT]。     

线性变位极谱研究 V:碲的吸附电流方程式

The mechanism of the electroreduction of Te(IV) has been studied, it is (TeO3)2- + 3H2O + 4e = (Teads)0 + 6OH- (1) (Teads)0 + H2O + 2e = (Hte)- + OH- (Teads)0 + 2e = Te2- The reaction scheme can generally be expressed as follows: ACcordingly, the equation of adsorptive current is give: i = 0.629 n2**2F**i/RT \n\(D0)1/2m2/3t7/6 \Pn\/(1+\Pn\)**2 (C0)* where \Pn\ = bAtA,7exp n2F/RT (E-E0)/& When \Pn\ = 1 the current reaches the maximum, ip = 0.157 n2**2F**2/RT \n\(D0)1/2m2/3t7/6(C0)* This equation shows that the peak current ip is proportional to m2/3t7/6, the ratio of potential change v and the concentration of the substance O being reduced. The half wave width, w1/2, can be obtained from the equation (6) in the form of the following expression W1/2 = 3.52RT/n2F The theoretical conclusions are in good agreement with experimental data for the adsorptive wave of tellurium in 0.25M NH3-NH4cl solution. The diffusion coefficient value determined agrees with that obtained by other polarographic method reported in the literature.     

分散体系中任意形状的胶粒模型与相互作用能——Ⅱ、不等同球颗粒

鉴于不等同球颗粒在胶体化学中的重要性,所以它一直引起人们在理论上的关注。Hogg、Healy和Fuerstenau(HHF)对Poisson-Boltzmann方程引用Debye-Hückl近似,得出不同平行平板型颗粒在恒电位表面时相互作用能计算公式,进而HHF用Derjaguin法得出不等同球颗粒相互作用能的表达式。虽然HHF的公式仅适用低电位的情况,但它的表达式特别简单,因而一直被广泛使用。Ohshima等(OCHW)对球颗粒做了曲率校正,Barouch等(BM)对Poisson-Boltzmann方程提出二维解法,使不等同球颗粒的相互作用能的计算有了改进和提高。本文根据我们提出的模型和方法,对HHF公式也做了曲率校正,结果表明它和OCHW的曲率校正结果相当,但它的表达式却要简单得多。     

细胞动力学研究 II.产物抑制生长过程的热动力学

By using an LKB2277 Bioactivity Monitor, we have determined the thermogenesis power curves of four kinds of Brucellas S2(55007), M5 (55009),83-202,83-980. And established the thermokinetic equation for the process of cell growth inhibited by the products of metabolism, as:
Ln[1/(β﹒Pt)-1]=ln[1/(β﹒P0)-1]-k0﹒t
From this equation, the rate constants of cell growth k [= k0(1 - β﹒P0)] were obtained. This thermokinetic equation is very suitable for cell growth of separated culture and is very important for the study of bacterial limited growth and their characteristics.     

Activation energy for the disproportionation of HBrO2 and estimated heats of formation of HBrO2 and BrO2

The kinetics of the reaction HBrO(2) + HBrO(2) --> HOBr + BrO(3)(-) + H(+) is investigated in aqueous HClO(4) (0.04-0.9 M) and H(2)SO(4) (0.3-0.9 M) media and at temperatures in the range 15-38 degrees C. The reaction is found to be cleanly second order in [HBrO(2)], with the experimental rate constant having the form k(exp) = k + k'[H(+)]. The half-life of the reaction is on the order of a few tenths of a second in the range 0.01 M < [HBrO(2)](0) < 0.02 M. The detailed mechanism of this reaction is discussed. The activation parameters for kare found to be E(double dagger) = 19.0 +/- 0.9 kJ/mol and DeltaS(double dagger) = -132 +/- 3 J/(K mol) in HClO(4), and E(double dagger) = 23.0 +/- 0.5 kJ/mol and DeltaS(double dagger) = -119 +/- 1 J/(K mol) in H(2)SO(4). The activation parameters for k' are found to be E(double dagger) = 25.8 +/- 0.5 kJ/mol and DeltaS(double dagger) = -106 +/- 1 J/(K mol) in HClO(4), and E(double dagger) = 18 +/- 3 kJ/mol and DeltaS(double dagger) = -130 +/- 11 J/(K mol) in H(2)SO(4). The values Delta(f)H(29)(8)(0)[BrO(2)(aq)] = 157 kJ/mol and Delta(f)H(29)(8)(0)[HBrO(2)(aq)] = -33 kJ/mol are estimated using a trend analysis (bond strengths) based on the assumption Delta(f)H(29)(8)(0)[HBrO(2)(aq)] lies between Delta(f)H(29)(8)(0)[HOBr(aq)] and Delta(f)H(29)(8)(0)[HBrO(3)(aq)] as Delta(f)H(29)(8)(0)[HClO(2)(aq)] lies between Delta(f)H(29)(8)(0)[HOCl(aq)] and Delta(f)H(29)(8)(0)[HClO(3)(aq)]. The estimated value of Delta(f)H(29)(8)(0)[BrO(2)(aq)] agrees well with calculated gas-phase values, but the estimated value of Delta(f)H(29)(8)(0)[HBrO(2)(aq)], as well as the tabulated value of Delta(f)H(29)(8)(0)[HClO(2)(aq)], is in substantial disagreement with calculated gas-phase values. Values of Delta(r)H(0) are estimated for various reactions involving BrO(2) or HBrO(2).     

细胞动力学研究VI. 厌氧菌生长过程热化学特征

用LKB2277生物活性检测系统测定了三种厌氧菌---吉氏类杆菌、艰难梭状芽胞杆菌、黑色消化球菌的生长发热功率曲线。根据广义logistic方程, 建立了细菌生长过程的热动力学方程:ln[P/(Pm-P)^v^+^1]=ln[P0/(Pm-P0)^v^+^1]+k.t。由此热动力学方程, 求得了细菌的生长常数k, 根据Arrhenius公式求得吉氏菌的生长活化能Ea=59.7kj/mol, 应用过渡态理论得到吉氏菌在不同温度下的活化力学参数, 这个热动力学方程描述的是一系列不规则的细菌生长过程发热曲线, 将它与经典的指数模型和logistic模型进行比较, 它具有更广泛的适用性。     

Kinetics of Anodic Dissolution of Some Metals in Electrolytes Based on Complexes of Triethylaluminum with Alkali Metal Fluorides and Tetraethylammonium Chloride

The dissolution kinetics of M* anodes (M* = Al, Cd, Sn, Sb, Bi) during electrolysis of molten complexes M[Al₂Et₆] (M = Na, K, Rb, Et₄N; = F, Cl) is studied. Parallel dissolution paths are discovered: through a limiting discharge of electrolyte components and through a limiting electrooxidation of adatoms and clusters of M* present at the electrode surface. Substantiated is a mechanism of electrosynthesis of ethyl derivatives M*Et _n involving the formation of adsorbed complexes (M*Et_{1 k n – 1})_ads via the scheme AlEt₄ ^– + M* – e M*(Et)_ads + (AlEt₃); M*(Et)_ads + (AlEt₄ ^–) – e = M*(Et₂)_ads + (AlEt₃); ...; M*(Et _{n – 1})_ads + (AlEt₄ ^–) – e AlEt₃ + M*Et _n .