氧化铝工业赤泥环境影响研究进展

赤泥是氧化铝工业生产过程排放的强碱性固体废弃物,盐分含量高、资源化利用难。外排赤泥以堆存方式为主,污染事故频发,赤泥环境安全问题正严重威胁氧化铝工业的可持续发展。在调研近30年国内外相关文献的基础上,综述赤泥的物理化学特性和生物学毒性,分析赤泥处置和资源化利用的环境影响,剖析赤泥堆场生态修复和基质改良的环境问题,解析赤泥库溃坝对周边土壤、水体和生态系统的环境风险,结合国内外氧化铝工业赤泥处置和资源化利用方面亟待关注的问题提出未来赤泥环境影响研究的重点方向。这将为赤泥资源化利用和规模化处置过程的环境风险防控管理、促进氧化铝工业的健康发展提供科学依据。     

纳米级ZnO-TiO2复合粉体的制备及其性能研究

利用ZnCl2,TiCl4为原料，用共沉淀法合成了ZnO-TiO2复合粉体，采用XRD、TEM和IR测试手段对纳米级的粉体结构和形貌进行研究，结果表明，通过控制反应条件可得到粒径为10－40nm的复合粉体。利用紫外－－可见分光光工地检测所得样品的吸收紫外线性能，发现所得纳米ZnO-TiO2复合粉体的紫外吸收性能高于纳米TiO2及市售微米级钛白粉，且纳米ZnO-TiO2复合粉体的紫外吸收随粒径的减小而加强。     

氧化铝清洁生产工艺现状及展望

清洁生产技术是实施可持续发展战略的重要手段.通过对氧化铝行业资源利用、生产工艺、环境保护现状的研究,论述了开展清洁生产技术的重要性和必要性,提出了在氧化铝生产过程中实施清洁生产技术的对策和措施,旨在于推进清洁生产工艺在氧化铝生产中的应用.     

Nanotechnology applications as a context for teaching the essential concepts of NST

The goals of this study are to map applications of nanotechnology that are recommended to be taught in high-school science and to identify the ‘need-to-know’ essential nanoscale science and technology (NST) concepts for each of the selected nanotechnology applications. A Delphi study using a community of experts was used to address these goals. Five nanotechnology applications that should be taught in high-school science were found to be important and reached a consensus by the Delphi-study experts: (1) nanomedicine, (2) nanoelectronics, (3) photovoltaic cells, (4) nanobots, and (5) self-cleaning. It was found that teaching these five nanotechnology applications should be based on all seven NST concepts, and therefore, these applications can be used as an appealing context for teaching the essential NST concepts. The different recommendations between the two communities of experts emphasize the importance of involving teachers and scientists in the process of designing a scientific curriculum. Identifying the applications of nanotechnology that should be taught in high-school science and identifying the connections between the applications and the essential NST concepts constitute an important step that supports designing a context-based nanotechnology program before it is integrated into a high-school science curriculum.     

室温固相合成法制备纳米Fe_2O_3粒子

分别以表面活性剂PEG-400和PEG-600为分散剂,FeSO4.7H2O和Na2CO3室温下发生固相反应,得到纳米氧化铁前驱体FeCO3,热解后即可得到产品.经TG/DTA、IR、XRD对前驱体及其热解产物进行表征,表明前驱体FeCO3极易分解成纳米Fe2O3,550℃热解得到了纯晶相的三方Fe2O3,粒度分别约为48.2 nm,50.7 nm.     

模板浸渍法制备聚苯胺纳米管阵列

利用模板浸渍法制备了准一维聚苯胺纳米管阵列．通过扫描电子显微镜观察可知：纳米管是中空的管状结构，纳米管的外径约230nm，与所用模板孔径基本相当．纳米管阵列排列整齐，长度均一，彼此相互平行，管径均匀．紫外-可见光谱证明：聚苯胺纳米管阵列中高分子链部分保留了在溶液中的伸展链构型．     

Agglomeration Control of Ultrafine Y_2O_3-ZrO_2 and (MgO, Y_2O_3)-ZrO_2 Powders Synthesized by Coprecipitation Process

TheadventofstrongandtoughZrO2 basedce ramicshasgeneratedconsiderablescientificandtech nologicalinterestinthisclassofstructuralceram ics[1—3]. Nowfine grainedsinteredceramicscanbeproducedusingcommerciallyavailableultrafinepow ders,whichcanbesinteredtofulldensityatrelativelylowtemperatures. High qualityZrO2 powderisvitalforthesuccessfuldevelopmentofadvancedZrO2 ce ramics. Severalwetchemicalmethodshavebeende velopedforpreparationofsuchhigh purity, homoge neousandsinterableceramicspowders,…     

冲击氧化铝单晶中失效波弛豫时间因子的测量

在冲击动压为133GPa的氧化铝单晶的冲击实验中,测量了在850nm处冲击氧化铝单晶的辐射曲线,发光信号显示被冲击压缩的单晶中存在延迟发射现象;该现象表明氧化铝单晶在冲击波到达后经历了一个再压缩过程,该过程可用失效波解释;通过实验曲线拟合到在133GPa下失效波的弛豫时间为0．107ms／cm．     

超细氧化镁的制备

以工业硫酸镁和草酸铵为原料,采用直接沉淀法合成了超细粉体氧化镁,并通过红外光谱(IR)、热重分析(TG-DTA)、X射线粉末衍射(XRD)、透射电镜(TEM)等手段对该纳米微粒的结构进行了表征.结果表明所制得的纳米氧化镁微粒呈立方晶格,形貌为椭球体,分散性好,粒径在25～35nm之间.考察了反应物浓度、加料方式和煅烧温度等各种因素对粉体质量的影响.     

Magnetic Properties of Nanocrystalline Fe60Cr40 Powders Prepared by Mechanical Alloying in Vacuum and Air

Magnetic properties of nanocrystalline Fe60 Cr40 powders prepared by mechanical alloying in vacuum and air were investigated by utilizing the measurements of magnetization, X-ray diffraction, and ^67Fe M（oe）ssbauer spectrum. The results show that the Fe60 Cr40 powders keep the bcc structure during milling in air and vacuum. The saturation magnetization of the Fe60 Cr40 powders milled in vacuum and air decreases with the increase of the milling time up to 45 h. The decrease of saturation magnetization of the Fe60Cr40 powders milled in vacuum is due to the formation of Fe-Cr solid solution, while in air it is due to the formation of paramagnetic disorder structure and solid solution.