用电势分析法解一段含源电路和复杂电路

在高中物理电路问题的教学中，经常用部分电路欧姆定律和全电路欧姆定律配合求解简单电路问题，但在求解一段含源电路和复杂电路问题时，采用这种方法往往无能为力。笔者在教学中尝试引入求解这类问题的有效方法一电势分析法，从而解决了上述困难，提高了学生对电路规律的认识．

固体氧化物电解质膜反应器在非均相催化中的应用

固体氧化物电解质池用作膜反应器 ,可以共生电能和化学产品 ;通过固体电解质电势分析法与动力学测量相结合可进行非均相催化反应机理研究 ;该膜反应器还可用于催化剂活性的电化学改性研究。本文主要从以上

Electrodeposition of dixanthogen(TETD) on pyrite surface

The electrochemical reaction of xanthate on the surface of pyrite was studied using cyclic voltammogrametry, chronopotentiometry and rotating-disc electrode measurements.Experimental results demonstrate that the first step in the reaction is electrochemical adsorption of xanthate ion,and then the adsorbed ion associates with a xanthate ion from the solution and forms a dixanthogen on the pyrite electrode surface.The diffusion coefficient of butyl xanthate on pyrite electrode surface can be determined to be about 1.09×10- 6cm2/s.Using the galvanostatic technique,the kinetic parameters of oxidation of the butyl xanthate ion on the pyrite surface are calculated as Ja=200μA/cm2 ,β=0.203 and J0=27.1μA/cm2.

Numerical modeling of the 2D time-domain transient electromagnetic secondary field of the line source of the current excitation

To effectively minimize the electromagnetic field response in the total field solution, we propose a numerical modeling method for the two-dimensional （2D） time- domain transient electromagnetic secondary field of the line source based on the DuFort- Frankel finite-difference method. In the proposed method, we included the treatment of the earth-air boundary conductivity, calculated the normalized partial derivative of the induced electromotive force （Emf）, and determined the forward time step. By extending upward the earth-air interface to the air grid nodes and the zero-value boundary conditions, not only we have a method that is more efficient but also simpler than the total field solution. We computed and analyzed the homogeneous half-space model and the fiat layered model with high precision--the maximum relative error is less than 0.01% between our method and the analytical method--and the solution speed is roughly three times faster than the total-field solution. Lastly, we used the model of a thin body embedded in a homogeneous half-space at different delay times to depict the downward and upward spreading characteristics of the induced eddy current, and the physical interaction processes between the electromagnetic field and the underground low-resistivity body.

基于COMSOL的矩形体内部缺陷圆的无损检测

针对矩形体内部缺陷圆的无损检测,利用COMSOL工具建立一个封闭式矩形电阻抗成像模型,安放阵列电极并施加电流激励。通过测量电极上的电压信号,计算相邻电极的电压变化率,利用电势差分析法对目标小圆圆心近似位置和半径大小进行定位。结果分析表明,缺陷信息和边界电压之间存在一一对应的关系,可通过测量边界电压获知矩形体内部缺陷信息,从而实现无损检测。

Hydrogen diffusion in Zr_(35)Ni_(55)V_(10) amorphous alloy

Hydrogen diffusion in Zr_(35)Ni_(55)V_(10) amorphous alloy was measured by chronopotentiometry. The results show that at lower molar ratio of hydrogen (x<0.06, x=n(H)/n(M)), the diffusivity of hydrogen increases rapidly with increasing the molar ratio of hydrogen. However, when x(H)>0.1, the diffusivity of hydrogen decreases slightly with increasing the molar ratio of hydrogen, which is similar to the change in crystalline alloy. It is proposed that hydrogen atoms mainly occupy the sites corresponding to tetrahedra with 4 Zr atoms at lower molar ratio of hydrogen. When the molar ratio of hydrogen is higher, the additional hydrogen atoms are in sites with higher energy and these sites in amorphous state are similar to these in crystalline states.

开放式电阻抗成像下的目标定位

给出一种开放式电阻抗成像中目标小圆圆心的近似位置和半径大小定位方法。利用Comsol multiphysics工具建立开放式电阻抗成像模型,测量并记录圆心在不同位置及半径大小不同时的各电极电势,计算相邻电极点之间的电势差。通过分析边界电势差与圆心的近似位置和半径大小的对应关系,利用电势差分析法和二分法进行目标定位。对比实验结果表明,相对电势差分析法可快速确定目标小圆的近似位置,具有普遍性;二分法可准确确定目标小圆的半径大小,具有较高精度。