Zweiparametrige Überrelaxation

Summary A generalization of the method of successive overrelaxation (SOR-method) toward the solution ofx=A x+b (the matrixA being of a special form) is treated. The method depends on two parameters instead of one but needs no more computational efforts. For matricesA with real and pure imaginary eigenvalues, those parameters are determined for which the method converges and those which give fastest convergence. The class of matricesA yielding convergence is enlarged in comparison to the SOR-method. The convergence is speeded up except in some cases. Three numerical examples are presented.     

Application of multicomponent spectrophotometry in analysis of copper electroplating bath solutions

Multiwavelength multicomponent analysis for copper and nickel is explored within the spectral range 230-900 nm in order to enable copper (?0.2 g l^?1) and nickel to be determined simultaneously even at high (20 l^?1) and nickel concentrations in industrial electroplating baths. Calibration based on pure-component spectra is compared to multivariate calibration based on data reduction with principal component analysis with the partial least-square algorithm. By use of multivariate calibration techniques, sulphuric acid can also be determined indirectly by its effect on the absorbance of the metal ions. The performance of the method is evaluated for different spectral ranges and the experimental results are related to the selectivity of the different systems quantified by the condition number of the actual absorptivity matrix.     

Analysis of flow dynamics in a new,very low pressure reactor. Application to the reaction: Cl + CH4⇌ HCl + CH3

A new, improved variant of the very low pressure reactor (VLPR) system with interchangeable discharge orifices was used for studying the compatibility of the chemical and physical processes occurring simultaneously. It is shown that the ratio of calculated and effective escape rate constants is a complex function of the reactor cell geometry for reactions of non-spherical symmetry. The test reaction of atomic chlorine with methane proved to be a pure chemical process free of side reactions and was used to calibrate the system. The measured rate constant is k₁ = (0.993 ± 0.013) × 10^-13 cm³/molec-s at 25°C. A new procedure is outlined for measuring the equilibrium constant by changing the concentrations of all three components resulting in a remarkable accuracy of K₁ = 1.406 ± 0.034 for the test reaction at 25°C.