β-球形氢氧化镍的微结构与热分解特征

利用热分析方法和扫描电子显微镜(SEM)对湿法制备的β-球形氢氧化镍的热分解特征及其与微晶形貌和大小之间的关系进行了研究。基于热分析数据,应用Arrhenius方程对氢氧化镍的失水热分解反应动力学进行了研究,结果表明:反应过程可能包括早期的由反应控制的阶段和后期的由扩散控制的阶段。随着组成氢氧化镍的球粒表面微晶大小和形态由粗粒片状至微细粒状变化,失水热分解温度降低,失水速率增大。因此,具有微细粒状边界模糊特征的氢氧化镍有更好的热传导性能并经测试证明具有更好的电化学活性。同时,良好的热传导性能将有利于MH-Ni蓄电池的高低温充放电特性的改善。     

纳米磁性金属电磁波吸收剂的研究进展及展望

分析了纳米磁性金属系材料的电磁波吸收机理,总结了近年来国内外对包括单元磁性金属粉、多元磁性合金粉、陶瓷基核/壳结构纳米磁性金属颗粒膜、磁性金属薄膜及纤维等磁性金属电磁波吸收剂的研究现状,指出纳米磁性金属材料有望满足新型吸波材料"薄、轻、宽、强"的要求,并提出了今后纳米磁性金属吸收剂的研究方向.     

超级电容器电极材料研究进展

超级电容器作为储能器件,与传统物理电容器相比较明显地提高了比容量和比能量,而与二次电池相比,虽然比能量低,但其比功率却有着数量级的增加.本文综述了用于制备超级电容器的三类电极材料碳材料、金属氧化物材料和导电聚合物材料的研究进展.     

Nanosized Nickel Oxides Derived from the Citrate Gel Process and Performances for Electrochemical Capacitors

Nanosized nickel oxide powders were prepared by thermal decomposition of the nickel citrate gel precursors. The thermal decomposition and powder materials derived from calcination of these gel precursors with various ratios of citric acid （CA） to nickel at different temperatures and times were characterized by thermal analysis （TG/DTA）, scanning electron microscopy （SEM）, x-ray diffraction （XRD）, and measurement of specific surface area （BET） with porosity analyses. The optimized processing conditions of calcination temperature 400℃ for 1 hour with the CA/Ni ratio of 1.2, were determined to produce the nanosized nickel oxide pow- ders with a high specific surface area of 181 m^2/g, nanometer particle sizes of 15-25 nm, micro-pore diameter distribution between 4-10 nm. The capacitance characteristics of the nanosized nickel oxide electrode in various concentrations of KOH solutions were studied by the cyclic voltammetry （CV） exhibiting both a double-layer capacitance and a faradaic pseudocapacitance. The nanosized nickel oxide electrode shows a high cyclic stability and is promising for high performance electrochemical capacitors.     

氧化铝纤维的研究现状与发展趋势

介绍了氧化铝纤维的主要应用领域、国内外研究发展现状以及市场前景，并提出了一种制备氧化铝纤维的新方法。     

二(2-乙基己基)磷酸在锌电积过程中的行为

用循环伏安法,X—光衍射、扫描电镜和X—射线能谱研究了HDEHP在锌电积过程中的行为。随电解液中HDEHP含量的增加,锌电积电流效率降低,活化超电位增大,晶面取向呈一定顺序(11.2)→(10.1)→(11.0)。活化超电位与晶面取向之间存在一定的关系。当HDEHP<10mgl~(-1),不会产生有机烧板,电锌具有较大的六方片状晶。有机烧板由萃取剂HDEHP引起而不是由稀释剂煤油引起的。烧板物由锌和HDEHP组成。根据电极过程动力学和晶体成长理论解释了实验结果。     

爆轰产物法合成纳米金刚石研究现状

介绍了爆轰法合成纳米金刚石在理论、制备及合成技术研究的现状，指出了影响纳米金刚石生产成本及制约其工业应用的关键在于爆轰产物的纯化和分散。强调改变工艺条件和对金刚石表面改性可得到不同需要的纳米金刚石产品。     

用数值模拟方法分析混合和导流筒对搅拌槽中沉淀硫酸钡的影响

1 INTRODUCTION Precipitation of sparingly soluble salts is an im- portant operation widely adopted in the production of functional materials, catalyst, protein, pharmaceutical product and pigment. By precipitation, two aqueous streams containing respective reactants are mixed in a precipitator, and the sparingly soluble salt forms as result of chemical reaction if the concentration of produced salt exceeds its solubility. The quality of the final product obtained by precipitation is strong…     

简报γ-FeNi包裹Al_2O_3复合微球的制备

利用非均相沉淀包裹技术,在室温于水溶液中,以球形αAl2O3、硫酸镍、硫酸亚铁和碳酸氢铵为原料,先制备了无定形碱式碳酸镍和水合氧化铁包裹氧化铝球形微粉前驱体。然后,前驱体在600℃经氢气还原2 h制备表面光滑、致密的γFeNi包裹Al2O3复合微球。利用扫描电镜、能量散射分光仪、X射线衍射和热重分析仪等表征了复合微球前驱体及还原产物的表面和断面形貌、成分以及前驱体热分解过程。对被包裹氧化铝含量、加料速度、搅拌速度、反应时间及表面活性剂等影响因素进行了分析。初步得到优化制备条件,即15 g/LαAl2O3,加料速度为5 mL/min,搅拌速度为1 000 r/min,反应时间为1 h,表面活性剂添加量为5 mL/L。γFeNi的热膨胀系数接近于氧化铝,因而使两者形成了较好的界面结合。这种γFeNi包裹Al2O3复合微球可用作新型吸波材料。     

Preparation of ferromagnetic binary alloy fine fibers by organic gel-thermal reduction process

Ferromagnetic metal fibers with a high aspect ratio （length/diameter） are attractive for use as high performance electromagnetic interference shielding materials. Ferromagnetic binary alloy fine fibers of iron-nickel, iron-cobalt and cobalt-nickel were prepared by the organic gel-thermal reduction process from the raw materials of critic acid and metal salts. These alloy fibers synthesized were featured with a diameter of about 1 pm and a length as long as 1 m. The structure, thermal decomposition process and morphologies of the gel precursors and fibers derived from thermal reduction of the gel precursors were characterized by FTIR, XRD, TG/DSC and SEM. The gel spinnability largely depends on the molecular structure of metal- carboxylates formed during the gel formation. The gel consisting of linear-type structural molecules shows good spinnability.