Bivariate Dispersion Control Charts for Monitoring Non‐Normal Processes

Multivariate control charts are well known to be more sensitive to the occurrence of variation in processes with two or more correlated quality variables than univariate charts. The use of separate univariate control charts to monitor multivariate process can be misleading as it ignores the correlation between the quality characteristics. The application of multivariate control charts allows for the simultaneous monitoring of the quality characteristics by forming a single chart. The charts operate on the assumption that process observations are normally distributed, but in practice this is not always the case. In this study, we examine and present multivariate dispersion control charts for detecting shifts in the covariance matrix of normal and non‐normal bivariate processes. These control charts, referred to as SMAX, QMAX, MDMAX and MADMAX, rely on dispersion estimates, such as the sample standard deviation (S), interquartile range (Q), average absolute deviation from median (MD) and median absolute deviation (MAD), respectively. We compare the performances of these charts to the existing multivariate generalized variance |S| and RMAX charts for bivariate processes using normal and non‐normal parent distributions. The average run length (ARL) measure is used for the evaluation and comparison of the charts. A real life and simulated datasets are used to demonstrate the application of the charts. Copyright © 2016 John Wiley & Sons, Ltd.     

Removal of copper ions from aqueous solution by adsorption using LABORATORIES-modified bentonite (organo-bentonite)

Equilibrium, kinetic and thermodynamic aspects of the adsorption of copper ions from an aqueous solution using linear alkylbenzene sulfonate (LABORATORIES) modified bentonite (organo-bentonite) are reported. Modification of bentonite was performed via microwave heating with a concentration of LABORATORIES surfactant equivalent to 1.5 times that of the cation exchange capacity (CEC) of the raw bentonite. Experimental parameters affecting the adsorption process such as pH, contact time and temperature were studied. Several adsorption equations (e.g., Langmuir, Freundlich, Sips and Toth) with temperature dependency were used to correlate the equilibrium data. These models were evaluated based on the theoretical justifications of each isotherm parameter. The Sips model had the best fit for the adsorption of copper ions onto organo-bentonite. For the kinetic data, the pseudo-second order model was superior to the pseudo-first order model. Thermodynamically, the adsorption of copper ions occurs via chemisorption and the process is endothermic (ΔH⁰>0), irreversible (ΔS⁰>0) and nonspontaneous (ΔG⁰>0).     

公益性地质工作引入竞争机制探讨

公益性地质工作引入竞争是促进地质事业改革的重大举措。根据地质工作特点,参照建设工程项目招投标管理模式,科学制定不同类型地质调查项目的竞争方式,健全完善竞争性选择地质项目承担单位的管理制度和操作规程是做好地质调查项目优选工作的重要内容。本文从问题引出、地质工作内涵分析入手,对地质调查项目竞争方式选择进行论述,并提出充分认识地质工作竞争重要性、健全完善制度、做好地质调查项目数据库建设与维护等相关对策建议,以推进公益性地质调查工作市场化运行,确保地质事业的蓬勃发展。     

Dispersion Characteristics of Dielectric Loaded Multiple V-Ridge Waveguide

A new kind of V-ridge waveguide is presented in this paper. The transmission problem is solved by edge element for the first time. The field patterns of the waveguide with single, double and triple V-ridge for different values of dielectric constant have been presented. Variations of the cutoff wavelength, single-mode bandwidth with the ridge dimensions for different values of dielectric constant are investigated in detail. The results will be of practical significance in designing ridge waveguide components in microwave and millimeter wave engineering.     

Insight into excitation wavelength and hotspot effect of noble metal nanoparticles dimer

A proper excitation wavelength and strong hot-spot effect are of great importance for the application of surface-enhanced Raman spectroscopy (SERS) in the field of biochemistry. As a popular SERS substrate, noble metal nanoparticles dimer is analyzed systematically in this paper. The hot-spot effect and the resonance peak position with varying geometric parameters of metal nanoparticles are investigated. Moreover, the excitation wavelength of bimetallic structure is discussed as well. The conclusions can provide reference for the selection of metal material at different excitation wavelengths.     

溴乙酰基二茂铁的合成及工艺优化

以氢溴酸和饱和溴水为溴化试剂,与乙酰基二茂铁反应合成了溴乙酰基二茂铁。目标化合物的结构经IR及1 H NMR确证。讨论了反应温度,氢溴酸用量、饱和溴水滴加速率对收率的影响,并通过单因素讨论和正交实验确定最佳反应条件为:反应温度0℃,HBr用量1.5mL(25mmol乙酰基二茂铁),饱和溴水的滴加时间2h。在最优条件下重复实验收率可达79.6%。与传统的合成工艺相比,以饱和溴水作为酰化试剂反应过程易控制,操作简便,成本低,反应时间短,后处理简单。     

国家网络空间安全国际战略研究

网络空间安全已成为国家安全的主要组成部分,在经济和社会发展中发挥日益重要的作用。本文立足全球网络空间安全的总体形势,着眼于我国面临的机遇和挑战,研究符合我国价值观和国家利益的国际网络空间安全战略,并提出了相应的战略目标、原则和任务。     

基于DPC31的Profibus-DP智能从站设计与实现

介绍了西门子公司DPC231芯片的结构和功能，并研究了基于DPC31芯片构成Proflbos-DP从站的硬件和软件设计方法，重点介绍了DPC31的初始化过程、中断处理和GSD件等。     

Facile preparation of sago starch esters using full factorial design of experiment

A facile solvent‐free method to acetylate sago starch (Metroxylon sagu) is reported. Microwave (100 W) was used as the heating source and the heating time was varied from 2 to 10 min with the temperature of acetylation maintained at 100°C under continuous stirring. Using a 2⁴ full factorial design of experiment, it was found that the degree of substitution (DS) of acetylated sago starch was strongly affected by the ratio of starch to acylating reagents, the ratio of acetic anhydride to acetic acid as the acylating reagents, the concentration of iodine as catalyst and reaction time. The physicochemical characteristics of the acetylated sago starch were assessed based on the FTIR spectra, the XRD spectra, the water absorption index (WAI), and the water solubility index (WSI). SEM was used to study the surface morphology of the acetylated sago starch at different DS.     

贵州化工的发展现状与展望

以贵州化工“九五”计划完成情况为重点叙述了贵州化工发展现状 ,并分析了存在的问题 ,根据贵州化工的“十五”计划展望了发展前景 ,并提出化学工业的合理布局和以结构调整为中心的发展战略