Growth and characterization of Pb0.97La0.02(Zr0.66Sn0.27Ti0.07)O3 antiferroelectric single crystals

Single crystals of Pb_0.97La_0.02(Zr_0.66Sn_0.27Ti_0.07)O₃ (PLZST) with the composition near the morphotropic phase boundary were grown by the flux method. The PbO–PbF₂–B₂O₃ system was used as a solvent. PLZST single crystals with the size of 4–6 mm are obtained and these crystals are slightly translucent after polishing. The splitting of (200) reflection peak indicates that the obtained crystals are of a single phase with tetragonal perovskite structure. The element contents of the grown crystals were measured by inductively coupled plasma atomic emission spectrometry. The chemical composition of the crystals is Pb_0.979La_0.014(Zr_0.666Sn_0.285Ti_0.049)O₃. Thermal properties and dielectric properties of PLZST single crystals were studied. The results show that flux-grown PLZST single crystals exhibit obvious endothermic processes and relaxor behaviors near the phase transition temperatures.     

A novel de-rusting method with molten salt precleaning and laser cleaning for the recycling of steel parts

Clean Technologies and Environmental Policy - Steel parts are a kind of high recovery value product for which de-rusting is the primary step in the recycling process. Laser cleaning is a popular...     

加氢装置加热炉易爆管部位的分析

重点介绍韩国蔚山炼油厂分馏塔底重沸炉火灾事故、中国石油化工股份有限公司洛阳分公司催化裂化柴油加氢装置反应进料加热炉火灾事故、茂名分公司渣油加氢脱硫装置分馏炉火灾事故、镇海炼油化工股份有限公司加氢裂化装置脱丁烷塔底重沸炉火灾事故的情况,找出加氢装置加热炉的易爆管部位,并通过分析总结,提出了易爆管部位的选材原则、设计改进方案及维护措施.     

EDTA interfacial chelation Ca2+incorporates superhydrophobic coating for scaling inhibition of CaCO3 in petroleum industry

In this paper,the superhydrophobic poly(vinylidene fluoride)/fluorinated ethylene propylene/SiO2/CNTs-EDTA(PFSC-EDTA)composite coating was successfully fabricat...     

Torsion sensor based on two cascaded long period fiber gratings fabricated by CO2 laser pulse irradiation and HF etching technique respectively

A novel torsion sensor is proposed, which is composed of one long period fibre grating and one asymmetrically corrugated long period fibre grating based on the high-frequency CO₂ laser pulses technology and burning fibre coating and etching cladding technology, respectively. By combing the advantages of the two aforementioned elements, a sensitivity of 331.7 and 310.3 pm/(rad/m) towards clockwise and anticlockwise direction, respectively, is reached in the experiments.     

CAD在三坐标测量机中的应用

近几年各个三坐标测量软件开发厂商相继在自己的软件中加入了CAD功能,且功能越来越强大。本文就CAD在三坐标测量软件中的使用和其功能作简要阐述。     

尖晶石相型LiM_(0.2)Mn_(1.8)O_4(M=Mg、Cd)相的晶格畸变与红外吸收峰频移

通过室温固相法制备了不同元素掺杂的前驱体,并采用分步煅烧法获得了尖晶石型LiMn2O4和LiM0.2Mn1.8O4(M=Mg、Cd)相。采用XRD和FTIR技术就元素掺杂对产物晶格畸变、Mn—O键长和键能强度等微观结构参数和光谱频移现象进行分析。结果表明,不同元素掺杂导致产物产生不同程度的晶格畸变。Mg元素掺杂使晶格收缩,Mn(Ⅳ)—O和Mn(Ⅲ)—O键收缩和键能强度增加,对应吸收峰发生蓝移;Cd元素掺杂使晶格膨胀,Mn(Ⅳ)—O和Mn(Ⅲ)—O键增长和键能强度降低,对应吸收峰发生红移。     

An efficient second‐order characteristic finite element method for non‐linear aerosol dynamic equations

In the paper we consider the non‐linear aerosol dynamic equation on time and particle size, which contains the advection process of condensation growth and the process of non‐linear coagulation. We develop an efficient second‐order characteristic finite element method for solving the problem. A high accurate characteristic method is proposed to treat the condensation advection while a second‐order extrapolation along the characteristics is proposed to approximate the non‐linear coagulation. The method has second‐order accuracy in time and the optimal‐order accuracy of finite element spaces in particle size, which improves the first‐order accuracy in time of the classical characteristic method. Numerical experiments show the efficient performance of our method for problems of log‐normal distribution aerosols in both the Euler coordinates and the logarithmic coordinates. Copyright © 2009 John Wiley & Sons, Ltd.