科技园地——废铅酸蓄电池铅料特点和冶炼技术选择

我国每年大约有五、六百万只废铅酸蓄电池产生，含铅金属量约为三、四十万吨，估计到2012年时，废旧蓄电池所含的金属铅量将达到50万吨。数量将明显增长，规格也变得更为多样。对废铅酸蓄电池进行综合回收利用，虽然取得了多项重大成绩，但仍然是当前国内再生铅行业面临的重要课题。     

废旧金属再生利有的探讨

我国的资源再生情况不容乐观.据预测,我国每年约有500万吨废钢铁、20多万吨废旧有色金属、200万吨废纸、100万吨废塑料、400万吨废化纤以及700万吨废玻璃、废旧电子产品等大量废弃物随垃圾丢弃而没有被回收利用.     

废碎玻璃亟需再生利用

废碎玻璃作为可持续利用的再生资源,其大量流失不仅浪费了本来就非常有限的能源、原料,还对土壤、地下水等宝贵资源造成了新的危害。据笔者调查,我国现有几百家玻璃生产企业,由于玻璃易碎,每年仅生产周转报废的酒瓶就达几十万吨。2006年沈阳市废碎玻璃量已从1994年的2.4万吨上升到10万吨,并且继续攀升;报废汽车回收公司每年回收的几千台报废汽车的玻璃没人回收,只得白白砸碎扔掉。目前沈阳市玻璃回收量只有15%,废碎玻璃回收、利用市场正逐年萎缩。     

挪威固体废弃物政策给我国的借鉴

目前，我国一方面是国内资源极大短缺；另一方面，每年约有500万吨的废钢铁，20多万吨的废有色金属、1400万吨的废纸及大量的废塑料、废玻璃、废旧电器等废弃物没有回收处理，回收率仅为40%左右，资源严重流失。我国的固体废弃物堆存量已达70多万亿吨，占用土地5亿平方米，对土壤，地下水，大气造成的现实和潜在的污染相当严重。     

“我们做的不是最好 但我们力求做得更好!”

在我国电子废弃物回收利用企业中,有一家企业在环境保护方面颇有特色,这就是位于东南沿海的台州市玉环县的青茂废旧物资有限公司。这家创建于1995年的民营电子废弃物回收利用企业拥有标准厂房面积14000平方米的废旧电子废弃物处理车间,是最早专业从事废电子元件报废线路板及边角料的集拆解、加工于一体的环保型企业,具有年处理各类报废线路板1万吨和年处理废旧家用电器100万台的生产能力。     

“我们做的不是最好 但我们力求做得更好!”

在我国电子废弃物回收利用企业中,有一家企业在环境保护方面颇有特色,这就是位于东南沿海的台州市玉环县的青茂废旧物资有限公司。这家创建于1995年的民营电子废弃物回收利用企业拥有标准厂房面积14000平方米的废旧电子废弃物处理车间,是最早专业从事废电子元件报废线路板及边角料的集拆解、加工于一体的环保型企业,具有年处理各类报废线路板1万吨和年处理废旧家用电器100万台的生产能力。     

发挥行业协会协调监督作用不断提高行业的自律意识

随着中国经济的高速发展,各行各业对各种基础材料的需求急剧增加,而国内资源严重短缺,矿产资源的保证度不断下降,从而促进了国内外再生资源开发利用产业的蓬勃兴起。2002年,我国进口含铜废料和废杂铜共308万吨,废杂铝44.7万吨,废锌5.5万吨。中国已经成为全球最大的废金属进口国,每年处理着全球废料市场上的三分之一的废旧金属。国外废杂金属的大量涌入,一方面给我国的基础材料工业带来了丰富的原料,显著缓解了我国有色金属矿产资源紧缺的局面;另一方面,我国在大量进口废杂金属、通过拆解加工与再生利用重新成为各种基础材料的同时,也给我国…     

废旧锌锰电池回收利用的研究现状

废锌锰电池中含有汞、镉、锌、铜、锰等重金属，随意丢弃，会对环境造成污染，也导致金属资源浪费。我国每年报废50万吨废锌锰电池，若能全部回收利用，可再生锰11万吨、锌7万吨、铜1.4万吨，是相当可观的资源。     

国内4月废铝进口环比降4．5％

近期中国海关公布4月废铝进口数据，4月我国共进口废铝21万吨，较3月份下降4．5％，1～4月累计进口78．4万吨，同比下降1．5％。进口成本高企以及再生铝需求不佳是4月我国废铝进口下降的主要原因。     

统计数据显示：中国再生有色金属产业快速发展

2006年，中国再生有色金属总产量达453万吨，比2005年增长21％。其中再生铜168万吨、再生铝235万吨、再生铅39万吨、再生锌11万吨，与2005年相比，分别增长18％、21％、39％和29％。据中国海关统计，2006年中国共进口有色金属废料实物量678万吨，比2005年增长3．1％。其中含铜废料494万吨、含铝废料177万吨、含锌废料7万吨，与2005年相比分别增长2．5％、5．3％、-5．3％。2006年中国国内回收废杂铜金属量68万吨、废杂铝金属量93万吨、废铅金属量39万吨。[第一段]     

Changes in the potential and vibrational energies upon the formation of vacancies in the oxygen-alloyed cores of crystallite-conjugation regions of polycrystalline Cr, Cu, and Ir

The changes in the potential and vibrational energies upon the formation of vacancies in the oxygen-alloyed (OA) cores of crystallite-conjugation regions (CCRs) in polycrystals of d transition metals Cr, Cu, and Ir have been determined. The potential energy increases upon the formation of vacancies (upon the formation of complexes of vacancies with oxygen atoms) in the OA cores of CCRs in the polycrystalline Cr, Cu, and Ir. However, the vibrational energy decreases upon the formation of vacancies in the OA cores of CCRs in these polycrystals, as in the OA cores of CCRs in polycrystals of the 4d and 5d transition bcc metals Mo, Ta, and W. The volume of the OA cores of CCRs in polycrystals of Cr, Cu, and Ir decreases upon the formation of vacancies. The changes in the interatomic interactions and dynamic properties in the regions of vacancy localization in the OA cores of CCRs coincide with analogous changes introduced into the lattices of metals by split interstitials.     

素质教育新视野

立足21世纪时代背景，以全新视角界定素质教育内涵。素质教育是一种全新的教育理念和教育思想。全面实施素质教育，标志教育理念深刻变革，教育思想的飞跃。素质教育的灵魂是道德教育，素质教育的核心是创新教育，素质教育的基础是人文教育，素质教育的方向是通才教育。     

NbFe合金的生产现状和发展

评述了中国及世界主要的NbFe合金生产厂家的生产能力、现状及世界钢铁工业对NbFe合金的需求状况,展望了中国NbFe合金的未来发展趋势.巴西CBMM公司是世界上最大的NbFe合金生产企业,最近几年NbFe合金生产能力已有相当大的提高,NbFe合金产量占世界总产量的70%以上,其中出口约14 800t.中国钢铁中铌的平均含量仅为美国和欧洲的15%,因此来自中国铌的需求量至少有6倍的增长空间.宁夏东方有色集团金联公司是中国最大的NbFe合金生产厂家,其NbFe合金生产量快速增长,2005年上半年达580t,占中国NbFe合金产量的75%以上.     

Influence of some anions on the stress corrosion of low alloy steels in aqueous solutions

Polarization and stress corrosion behaviour of two types of low alloy steels, AISI 4130X and AISI 4145, were studied in agitated 0.05 M sodium acetate and 0.05 M trisodium phosphate solutions saturated with natural gas at room temperature. The magnitude of currents, shown in potentiokinetic polarization curves in the range of —0.8 V(SCE) to +0.8 V(SCE) in these media, is very small compared with earlier results obtained in sulphate and chloride solutions.Stress corrosion experiments conducted using a slow strain rate technique under cathodic conditions indicate the onset of hydrogen embrittlement on both types of steel in sulphate, chloride, acetate and phosphate solutions. Under anodic conditions, the results in 0.05 M sodium acetate solutions indicate strong susceptibility to stress corrosion compared with no susceptibility in 0.05 M trisodium phosphate solutions if there is no onset of pitting. These results are in contrast with results showing strong anodic dissolution and consequent absence of stress corrosion under anodic conditions in sulphate and chloride media.Results of Auger and IR analyses of anodic surface films formed in acetate and phosphate solutions are presented and discussed in relation to their observed mechanical behaviour.     

DISTRIBUTION OF SULFUR IN HIGH TEMPERATURE PHASES OF CAST IRON

The distribution of subversive element sulfur in high temperature phases during solidificationof cast iron was investigated by means of liquid quenching method and autoradiography.Theresults show that in grey cast iron,sulfur is concentrated in the liquid,flake graphite and in theperipherial area of D-type supercooled graphite eutectic cells,but less sulfur is in austenite.Besides,the content of sulfur in A-type graphite is higher than that in D-type graphite,andsulfur content in eutectic austenite is a little higher than that in primary austenite.While,innodular graphite cast iron less sulfur is in liquid and austenite,but more in nodular graphite.The blackness of the spots on the emulsion film corresponds to the atomic percentage ofradioactive substances located on the surface of the specimen.     

热处理对SiCp/Al复合材料强度和塑性的影响

采用粉末冶金法制备了d300 mm的15%SiCp/Al(体积分数)复合材料坯锭,研究了挤压态和T4态复合材料的力学性能和断裂特点,揭示了基体强度和颗粒开裂对复合材料强度与塑性的影响规律。结果表明:复合材料T4态拉伸强度保持在560 MPa的水平下,延伸率仍高达7%以上;与挤压态相比,T4态复合材料拉伸强度和屈服强度分别提高了68.5%和105%,但塑性保持在同一水平。断口观察表明:挤压态复合材料以基体断裂为主,而T4态复合材料除了基体断裂外,还存在SiC颗粒开裂现象;基体强度严重影响复合材料的断裂形式,颗粒开裂有利于提高复合材料的塑性。     

Two decades of change in graduate education in metallurgy/materials—A perspective

It is now almost a decade since the introduction of massive federal support to universities for graduate education and research in the materials field. Accordingly, it is appropriate to examine the changes in the nature and activity of the field which have occurred during this period, both in the universities themselves, and in professional practice in industry and government, and also the implications of such changes for graduate education in metallurgy and materials science in the future.The present paper examines the growth of relevant university activities in the field over the past 10 years in comparison with that during the preceding decade and with the growth of engineering, science and advanced education in general in the United States, i.e., the question of the supply of new personnel with advanced training in the materials field. While it is appreciated that the nature and quality of education must be of prime importance, this paper deals principally with the numerical aspects of graduate education in materials, rather than with the philosophy, as a necessary first step in the broader study which is advocated.     

砒石对哮喘小鼠白三烯B4 及5-脂氧合酶基因表达的影响

目的: 探讨白三烯B4 (LTB4) 水平、5-脂氧合酶(5-LO) 基因表达在小鼠哮喘发病中的作用以及砒石(arsenolite, As) 对哮喘的治疗作用与LTB4 水平及5-LO 基因表达的关系。方法: 建立小鼠卵蛋白哮喘模型, 灌胃给予砒石等药, 用ELISA 的方法检测支气管肺泡灌洗液(BALF) LTB4 含量;用RT-PCR 的方法检测肺组织中5-LO mRNA 表达的变化。结果: 哮喘小鼠BALF 中LTB4 水平、肺组织5-LO 基因表达水平较正常对照组显著升高。4 种剂量的砒石均可抑制哮喘小鼠BALF 中LTB4 的水平, 均能降低哮喘小鼠5-LO mRNA 表达的量。其中砒石5.00 mg·kg^-1 剂量的效果优于砒石0.625 mg·kg^-1剂量的效果。结论: LTB4 在气道中的高水平, 5-LO 基因表达的上调在OVA 致敏小鼠的哮喘发病中起重要作用。砒石可显著降低哮喘小鼠BALF 中LTB4 水平, 抑制哮喘小鼠肺组织中5-LO 基因的表达, 从而表现出抗哮喘的活性。     

Formation of Mesoferrite and Granular Bainite in Low-Carbon Low-Alloy Steel

Special features in the formation of mesoferrite and granular bainite in low-carbon low-alloy steels are considered. A diagram of isothermal decomposition of austenite in steel 20Kh2NAch is plotted and the range of existence of mesoferrite is determined. Morphological differences between the granular intermediate structure formed in the isothermal decomposition of supercooled austenite in the intermediate temperature range and the granular bainite formed in the decomposition of austenite in continuous cooling are determined. The role of mesoferrite in the formation of these structures is considered.     

我国锻造行业模具与润滑现状及其发展方向

在综合分析我国锻造行业模具使用与润滑状况的基础上,论述了我国锻造行业与国外锻造行业模具及润滑技术上的差距,并对"十二五"期间我国锻造行业模具及润滑技术发展提出了建议。