自动定量秤工作原理及其分装误差分析

叙述了三种粉料自动定量秤的基本工作原理,并对影响其分包重量误差的主要因素进行了分析,指出了三种定量秤可能实现的分包重量误差数值。     

Experience in evaluating the data of inter-laboratory comparisons for calibration and verification laboratories

Results are presented for approval and comparative analysis of the suggested algorithms and criteria for actual experimental data of inter-laboratory comparisons performed in calibration and verification laboratories of the Belorussian Republic. __________ Translated from Izmeritel’naya Tekhnika, No. 6. pp. 15–21, June, 2007. The article was written for presentation at the fourth international seminar “Mathematical, statistical, and computer support for the quality of measurements.” (see Izmeritel’naya Tekhnika, Nos. 2–5, 2007).     

Chemical Degradation in Organic Light‐Emitting Devices: Mechanisms and Implications for the Design of New Materials

Degradation of the materials in organic light‐emitting devices (OLEDs) is the major impediment for the development of economically feasible, highly efficient and durable devices for commercial applications. Even though this chemical degradation is complex and the least understood of the different degradation modes in OLEDs, scientists were successful in providing insight into some of the responsible processes. In this progress report we will review recent advances in the elucidation of chemical degradation mechanisms: First possible reasons for defect formation and the most common and important methods to investigate those processes are covered before discussing the reactions and their products for the different types of materials present in a device. We summarize commonalities in the occurring mechanisms, and identify structural features and moieties that can be detrimental to operational stability. Some of the resulting implications on the development of new materials are presented and backed by concrete examples from literature.     

粘胶活性碳纤维预浸剂的热分解作用及效能评选

用热失重分析方法研究了磷酸铵盐、磷酸、硫酸铵对粘胶纤维的热分解促进作用.空气的存在有利于磷酸氢二铵对粘胶的分解反应,但对其余几种的影响不大.本文提出用峰高/半高宽之比表征热分解峰的形态.该值越低,即热分解峰越平坦,表明反应越缓和,则越有利于提高粘胶纤维的碳化活化得率.实验结果证实了这一观点.磷酸氢二铵/粘胶的热分解峰最平坦,作用效果最好;磷酸二氢铵和磷酸相当,磷酸铵次之,硫酸铵作用时比表面积很低.未预浸处理的粘胶热分解最激烈,产品得率和比表面积也最低.     

A Petrov–Galerkin formulation for the alpha interpolation of FEM and FDM stencils: Applications to the Helmholtz equation

A new Petrov–Galerkin (PG) method involving two parameters, namely α₁ and α₂, is presented, which yields the following schemes on rectangular meshes: (i) a compact stencil obtained by the linear interpolation of the Galerkin FEM and the classical central finite difference method (FDM), should the parameters be equal, that is, α₁ = α₂ = α; and (ii) the nonstandard compact stencil presented in (Int. J. Numer. Meth. Engng 2011; 86:18–46) for the Helmholtz equation if the parameters are distinct, that is, α₁ ≠ α₂. The nonstandard compact stencil is obtained by taking the linear interpolation of the diffusive terms (specified by α₁) and the mass terms (specified by α₂) that appear in the stencils obtained by the standard Galerkin FEM and the classical central FDM, respectively. On square meshes, these two schemes were shown to provide solutions to the Helmholtz equation that have a dispersion accuracy of fourth and sixth order, respectively (Int. J. Numer. Meth. Engng 2011; 86:18–46). The objective of this paper is to study the performance of this PG method for the Helmholtz equation using nonuniform meshes and the treatment of natural boundary conditions. Copyright © 2011 John Wiley & Sons, Ltd.