An index for deformation controllability of small-volume materials

Mechanical tests on small-volume materials show that in addition to the usual attributes of strength and ductility,the controllability of deformation would be crucial for the purpose of precise plastic shaping.In our present work,a"mechanical controllability index"(MCI)has been proposed to assess the controllability of mechanical deformation quantitatively.The index allows quantitative evaluation of the relative fraction of the controllable plastic strain out of the total strain.MCI=0 means completely uncontrollable plastic deformation,MCI=∞means perfectly controllable plastic shaping.The application of the index is demonstrated here by comparing two example cases:0.273 to 0.429 for single crystal Al nanopillars that exhibit obvious strain bursts,versus 3.17 to 4.2 for polycrystalline Al nanopillars of similar size for which the stress-strain curve is smoother.     

Laser micro-bending process based on the characteristic of the laser polarization

The laser polarization is a basic characteristic of CO₂ and solid-state lasers. The material's absorptivity to laser is dependent upon the laser incident angle. Thus, the laser polarization can be utilized to control the bending angle by changing the laser incident angle during laser bending. The laser polarization is introduced into laser micro-bending, and an experimental system is established. Laser micro-bending process based on the characteristic of the laser polarization is realized. For uncoated stainless steel specimen, the bending angles acquired at bigger incident angles are bigger than those acquired at zero incident angles. The bending angles increase linearly with the increase of the incident angle when the incident angle changes from 60° to 80°. During laser multi-scan bending, the final bending angle no longer varies with the scanning number, and approximately equals to the complement angle of the incident angle when it approaches to the complement angle. By means of adjusting the laser incident angle and scanning velocity, unfinished and finishing laser bending can be realized to satisfy the forming efficiency and accuracy. The absolute error between the final bending angle and the expected angle is less than 0.1°.     

耐热合金与耐热钢扩散焊接头微变形的研究

针对耐热合金与耐热钢的真空感庆扩散焊,研究了散焊连接工艺参数对接头变形率的影响、接头变形率与接头性能的关系以及不同接头变形率的微观形态。     

Properties of Ni doped and Ni-Ga co-doped ZnO thin films prepared by pulsed laser deposition

ZnNiO and Zn(Ni,Ga)O thin films were prepared on glass substrates by pulsed laser deposition. The obtained films are of good crystal quality and have smooth surfaces, which have a hexagonal wurtzite ZnO structure with a highly c-axis orientation without any Ga or Ni related phases. Hall-effect measurements showed that the ZnNiO film is n-type, in which the carrier concentration would be greatly enhanced by the addition of Ga. Room temperature ferromagnetism is observed for the ZnNiO and Zn(Ni,Ga)O films. The addition of Ga into the ZnNiO films increases the electron concentration but weakens the room temperature ferromagnetism.     

现代化呼叫中心在钢铁行业的应用

本文主要阐述呼叫中心的技术发展格局,以及与传统呼叫中心相比的优势所在。当今社会,企业间的竞争已由单纯的品种和价格的竞争,变为服务质量的竞争,所以在钢铁行业推广呼叫中心尤为重要。论文对钢铁企业呼叫中心的解决方案、功能要求和网络构成、硬件参数特性以及呼叫中心软硬件设备的兼容性和扩展性都做了详尽的探讨。     

邯钢程控测试系统改造

为了满足测试设备集中管理的要求,提高电讯维护管理工作的自动化水平,开发了测试联网系统。该系统投入使用后,不仅大大提高了测量的工作效率,而且极大地减轻了线路维护人员的劳动强度。     

Synthesis of CdS/CNTs photocatalysts and study of hydrogen production by photocatalytic water splitting

A series of CdS and CdS/CNTs photocatalysts were successfully prepared by hydrothermal method and they were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), UV–visible optical absorption spectra (UV–Vis), etc. By studying their photocatalytic properties, it is found that, for CdS, photocatalysts prepared in appropriate alkaline environment presented higher hydrogen production activity, reaching 794.6 μmol h⁻¹ g⁻¹; the photocatalytic activity of CdS was obviously enhanced by combining it with CNTs via a special two-step hydrothermal method, and the corresponding hydrogen production rate reached 1.771 mmol h⁻¹ g⁻¹; the photocatalytic activity was further improved by loading co-catalyst NiS, achieving 12.13 mmol h⁻¹ g⁻¹.     

Preparation of Cu(In,Ga)Se2 thin films by pulse electrodeposition

Cu(In,Ga)Se₂ thin films were prepared from aqueous solution by pulse electrodeposition. It was found that the co-deposition of the species occurred under a 3D growth with instantaneous nucleation. The morphology of the pulse-electrodeposited film can be improved by adjusting the duty cycle. The significant loss of indium and reduction of In-Se compound(s) accordingly were observed with decrease of duty cycle. Chalcopyrite structure Cu(In,Ga)Se₂ films with p-type behavior and enhancement in crystallinity were obtained after annealing treatment in Ar atmosphere.     

国际互联网带宽与流量现状及对我国运营商的建议

2009年以来,国际互联网流量增长加快,带宽利用率提升。互联网流量的增长与下一代网络和宽带互联网发展紧密相关,也受3G接入、智能终端等普及的影响。在业务和应用方面,视频和社交网络是流量增长的主要驱动力。我国运营商可以灵活的计费模式,积极推动宽带发展,以多种接入方式破解流量难题。     

二安替比林间甲氧基苯基甲烷光度法测定钢样中的锰

在碱性介质中，空气氧化Ｍｎ（Ⅱ）为Ｍｎ（Ⅳ），然后在磷酸介质中，Ｆｅ３＋存在下，Ｍｎ（Ⅳ）和二安替比林间甲氧基苯基甲烷（ＤＡｍＭＭ）反应生成橙色产物，λｍａｘ＝４８０ｎｍ，ε＝２５６×１０４Ｌ·ｍｏＬ－１·Ｃｍ－１。锰的含量在０～５０μｇ／２５ｍＬ内符合比尔定律，方法用于钢样中锰的测定，结果满意。