AA1235铝箔坯料的中温相转变

研究了AA1235铝箔坯料中温温度范围内相形成和转变的规律。结果表明,AA1235铝箔坯料在中温温度范围内存在两个相变反应:一个是从铝基体中析出α(AlFeSi)相的脱溶相变,另一个是β′(AlFeSi)→α(AlFeSi)的相变;α(AlFeSi)相的尺寸非常细小,在nm数量级;中间退火过程中Fe、Si元素在铝基体中的固溶度存在一极小值点,即最佳固溶贫化点,该现象的存在是上述两个对固溶度的变化起相反作用的相变过程共同作用的结果。     

在可溶性聚合物体系中光化学法制备Pd纳米粒子的研究

研究了在可溶性聚合物体系中Pd纳米粒子的光化学合成.Pd(Ⅱ)-PEG-丙酮溶液以紫外波长300nm光辐照,获得了胶体Pd纳米粒子并对其进行TEM表征.结果表明,Pd粒子的平均粒径为1.8～5.7nm,具有好的分散性.研究了各种组分的影响,探讨了体系中Pd(Ⅱ)的快速光化学还原和纳米Pd粒子的稳定性机理.     

2005年上半年我国钛工业的运行情况

2005年上半年，我国共生产海绵钛3801．6t，同比增长68％；生产钛粉342．5t，同比减少了76．5t；生产钛加工材5033．9t，同比增加了17％。2005年上半年，我国海绵钛进口量大幅减少，仅642t，钛加工材却大幅增加，达3024t。尽管从2004年开始，海绵钛及钛加工材价格大幅t涨，但我国对海绵钛和加工材的需求乃明显上升，预计2005年我国海绵钛的需求在万吨左右，而实际产量估计达到9000t左右，与实际需求稍有差距。世界海绵钛的生产能力不断扩大，预计2005年全球海绵钛的供应能力将增加23％，下半年海绵钛价格将趋于平稳。     

Thermoelectric properties of mechanically alloyed iron disilicides consolidated by various processes

Mn doped p-type iron disilicide powders have been produced by a mechanical alloying process. As-milled powders were of metastable state and mostly transformed to β-FeSi₂ phase by subsequent isothermal annealing. As-milled powders were consolidated by various processes such as sintering of the cold compact in vacuum, vacuum hot pressing (VHP), and spray drying/atmospheric plasma thermal spraying. Phase transitions during the processes were investigated using XRD, EDS, and SEM. As-consolidated specimens consisted of a mixture of α-Fe₂Si₅ and ε-FeSi phases, which were gradually transformed into a thermoelectric semiconducting α-FeSi₂ phase by subsequent isothermal annealing in the vicinity of 845°C in vacuum. However, some residual α and ε phases remained even after prolonged annealing. Thermoelectric properties were measured as a function of temperature and correlated with phase transformation. They showed optimum values in the vacuum hot pressed specimen due to a higher fraction of β phase and/or higher density.     

气相缓蚀剂的研究现状与展望

从缓蚀剂的缓蚀基团和分子结构方面概述了气相缓蚀剂的研究现状，阐述了气相缓蚀剂的有关缓蚀机理。分析了缓蚀效果的影响因素．讨论了气相缓蚀剂的发展方向．     

乙二醇水热还原法制备纳米银

利用乙二醇在高温下的还原特性,在水热条件下制备了纳米银粒子,并通过透射电镜、X射线衍射、紫外吸收光谱对其结构进行了表征.研究结果表明:所制备的纳米银具有面心立方相的多晶结构,平均粒径在30nm左右,紫外吸收峰的位置在380 nm左右.分散剂和体系中含水量对纳米银的粒径有一定影响.     

Electrochemical properties of Mg-based alloys containing carbon nanotubes

In this work, effects of partial substitution of Mg, Ni with AB₂ in Mg-based alloy and subsequent surface modification by further ball-milling with carbon nanotubes (CNTs) on electrochemical properties were investigated. Mg_1.9(AB₂)_0.1Ni_0.8 (AB₂=LaNi₂, LaNiCo and LaNiMn) alloys were prepared by solid-state diffusion method, the nanocrystalline Mg-based alloys were prepared by ball-milling the mixture of obtained Mg_1.9(AB₂)_0.1Ni_0.8 alloys and nickel powder. It was found that the electrochemical capacities of nanocrystalline Mg_1.9(AB₂)_0.1Ni_1.8 alloys were measured to be 460–490 mAh/g. The nanocrystalline Mg-based alloys containing carbon nanotubes (10 wt.%) obtained by ball-milling after 60 min were demonstrated to show improved electrochemical properties with respect to the original nanocrystalline Mg-based alloys. The electrochemical reaction activity was detected by electrochemical impedance spectra (EIS). Raman and X-ray photoelectron spectroscopy (XPS) proved the interaction between Mg_1.9(AB₂)_0.1Ni_1.8 alloys and carbon nanotubes after ball-milling, which resulted in an increase in the surface Ni/Mg ratio.     

激光淬火铁基烧结材料的摩擦与磨损

研究了两种不同成分铁基烧结材料经宽带激光表面处理后的显微组织和摩擦学特性。结果表明，铁基烧结材料的耐磨性显著提高。两种材料相比，在较低载荷下，组织为孪晶马氏体／位错马氏体混合材料具有较好的摩擦学特性。而在较高载荷下，组织为马氏体／下贝氏体复相的材料具有较好的摩擦学特性。     

FeAl/FeAlSi非对称膜材料的制备及膜基结合性能

目的制备高温腐蚀环境下应用的Fe Al/Fe Al Si非对称膜材料,研究膜与基体的结合性能。方法采用粉末反应合成法制备大孔径、高孔隙度的FeAlSi多孔体作为支撑体,通过浸渍法在支撑体表面制备小孔径的FeAl涂层作为膜层,再经烧结得到Fe Al/Fe Al Si非对称膜材料。研究Fe Al/Fe Al Si非对称膜材料的孔结构性能及膜基结合性能。采用XRD和SEM研究多孔膜材料的物相组成及微观形貌,采用孔结构测试仪及压汞法测试支撑体与膜层的孔结构参数,采用拉伸法和反吹实验研究Fe Al/Fe Al Si非对称膜材料的膜基结合性能。结果 Fe Al/Fe Al Si非对称膜材料表面膜层均匀、完整,膜层与支撑体之间具有冶金结合。支撑体的孔隙度和平均孔径分别为43.0%和22.7μm,膜层的孔隙度和平均孔径分别为36.5%和7.5μm。当膜层厚度增加时,膜材料的透气度下降,最大孔径在一定膜层厚度范围内变化不大,当膜层厚度在150～300μm范围内时,最大孔径约为7.8μm。膜层与支撑体的结合强度大于5.5 MPa。结论浸渍法制备的Fe Al/Fe Al Si非对称膜材料的孔结构性能优异,膜基结合性能满足工业应用。     

用偏钛酸作原料制备纳米TiO2粉末以及颗粒相结构与光催化性能关系的研究

米用常温氨水水解TiOSO4过程中加入自制的表面活性剂制备了超细纳米TiO2粉末,用XRD,TEM和比表面仪对不同煅烧温度下的纳米TiO2粉末结构、粒径大小和比表面等进行了表征,研究了纳米TiO2粉末对甲基橙的光催化降解能力。研究表明煅烧温度在400℃～800℃时得到的纳米TiO2粉末呈锐钛矿结构,粒径约为5．5nm～9．6nm,比表面积高达189．45m^2/g;在850℃煅烧后所得的纳米TiO2粉末为锐钛矿与金红石型混晶结构;在l100℃时得到的纳米TiO2粉末为金红石型纳米TiO2粉末,同时微粒出现团聚且粒径变大。光催化实验表明：纳米TiO2粉末的光催化活性与煅烧温度密切相关,850℃煅烧1．5h所制得的混晶结构纳米TiO2粉末表现出较高的光催化活性。与国产商品纳米锐钛矿型TiO2相比,其降解甲基橙的速率约为国产商品纳米TiO2的1倍。