表面活性剂对锌精矿在浆萃取浸出率的影响

研究了几种不同的表面活性剂对锌精矿有机溶剂在浆萃取过程中锌浸出率的影响 ,并对表面活性剂的用量对锌精矿在有机溶剂中的行为进行了探讨 ,测定了经表面活性剂处理后矿粉在水溶液中的粘度以及浸出溶液表面张力变化情况 ,结果表明加入 0 .0 5～ 0 .2 g/L表面活性剂十二烷基磺酸钠改变了矿粉在水溶液中的润湿性 ,降低了浸出溶液的表面张力 ,有效地提高了锌精矿浸出率     

Al掺杂锰酸锂材料在水系锂离子电池中的循环稳定性

水系锂离子电池具有优良的安全性能和高离子导电性等优点,得到了广泛研究.LiMn2O4材料在水系锂离子电池中较差的循环稳定性使其应用受到限制.为了改善这一缺陷,以乙炔黑为模板,采用简单的高温固相法合成了Al掺杂的LiMn2O4材料(LiMn1.9Al0.1O4),并应用于水系锂离子全电池中.实验结果表明,在0.1 A/g的电流密度下,LiMn2O4材料放电比容量高达125.5 mA·h/g,略高于LiMn1.9Al0.1O4材料的比容量(121.6 mA·h/g).在0.1 A/g电流密度下,经200次循环LiMn1.9Al0.1O4材料的容量保持率(90％)高于LiMn2O4材料(78％).将电流密度提升到1 A/g经500次循环后LiMn1.9Al0.1O4和LiMn2O4材料的容量保持率分别为88％和57％.上述结果表明Al掺杂的锰酸锂材料在水系锂离子电池中的循环稳定性以及倍率性能均有明显提高,说明Al的掺杂能显著提升锰酸锂正极材料的结构稳定性,并且能够缓解Mn的溶解和抑制Jahn-Teller效应,改善循环性能.     

系列Pt-X合金型PEMFC阳极催化剂的制备及表征

引言质子交换膜燃料电池(PEMFC)除具有燃料电池的一般特点之外,还具有可在室温下快速启动、无电解质流失、寿命长、比功率与比能量高等突出优点,因而成为当今最具发展前景的一类燃料电池。由于工作温度低于100℃,主要采用过电势较低且活性较高的Pt为电催化剂,因此它存在价     

表面活性剂对HCl-FeCl3溶液中锌精矿在浆萃取浸出率的影响

The effects of surfactant on the solvent extraction in leaching sphalerite were investigated. It is found that sodium dodecyl sulfonate is the effective surfactant in improving the zinc recovery from sphalerite in the aqueous FeCl3-HCl-tetrachloroethylene system. Through the measurements of surface tension and viscosity of the sphalerite slurry modified with different surfactants, it is concluded that sodium dodecyl sulfonate in the concentration range of 0.05 to 0.2g L-1 can improve the viscosity of sphalerite slurry in the water, decrease the surface tension of leaching solution, prevent the aggregation of ore particles, and give very high zinc extraction .     

直接甲醇燃料电池用新型质子交换膜的研究

以聚醚醚酮(PEEK)为原料,浓硫酸为磺化剂制备了不同磺化度的磺化聚醚醚酮(SPEEK)膜,以及磺化聚醚醚酮与聚乙烯醇(PVA)、正硅酸乙酯(TEOS)、磷钨酸的复合膜.分别对膜的电导率、阻醇性能和吸水率进行了研究.随着SPEEK膜磺化度的增大,膜的电导率有所提高,然而甲醇渗透系数也增大,膜的机械强度明显降低.SPEEK膜的吸水率低于Nafion 115膜,而PVA膜的吸水率则过高.     

一类超临界椭圆方程组正解的存在性

讨论了n≥3维球域上具零边值的一类椭圆方程组,Henon型椭圆方程组,它是Lane-Emden方程组的变形,即其主要非线性项各有一个在球心取零值的对称权重.通过建立对称Sobolev函数空间到加权Lp空间的嵌入定理,证明存在一条关于所论方程组非线性项指数(p,q)的双曲线,称为Henon双曲线,它位于临界Hardy-Littlewood-Sobolev曲线上方,使得对于Henon双曲线下方的点(p,q),方程组具有一组非平凡解.     

浸渍α-Ni(OH)2稳定性的研究

通过X射线衍射 (XRD)分析证实含B添加剂的镍电极活性物质晶型结构为α型 ,差热 热重 (DTA TG)分析则表明α Ni(OH) 2 层间有结构水或化学吸附水存在。探讨了添加剂B分别与Na2 S、Ca(NO3) 2 共沉积的镍电极性能。通过XRD及 50多次大电流充放电循环表明 ,该电极仍具有α型结构 ,且大电流放电容量的衰减受到一定程度抑制。     

Studies of Heterogeneous Hydrothermal Stripping from Iron-loaded Naphthenic Acid–Alcohol–Kerosen

The technique of hydrothermal stripping from mixed aqueous-organic systems is a promising method for synthesizing oxide ceramic powders for high-performance applications. Some factors influencing heterogeneous hydrothermal stripping with water from iron-loaded organic phase of naphthenic acid–isooctyl alcohol–kerosene, such as initial concentrations of iron and naphthenic acid, concentration of Fe2O3 “seed”, temperature and time, were investigated. Based on the experimental results, the rate equation was established. Nano-ferric oxide powders were obtained by the technique of hydrothermal stripping from the iron-loaded organic phase. The results suggest that the heterogeneous hydrothermal stripping proceeds in 3 steps: adsorption of naphthenic acid dimers and naphthenic complex of iron onto the surface of “seed”, hydrolysis of adsorbed complex of iron, and condensation of hydrolyzed complex. The process activation energy is 115 kJ/mol and the heterogeneous hydrothermal stripping is controlled by a chemical reaction (the hydrolysis of naphthenic complex of iron).     

直接甲醇燃料电池用碳气凝胶载铂催化剂的研究

利用溶胶—疑胶方法制备了高比表面积的碳气凝胶,利用浸渍还原法制备了Pt/碳气凝胶和Pt/C催化剂。采用BJH和TEM考察碳气凝胶的孔径分布和金属粒子的大小与分布,循环伏安曲线测试考察Pt/碳气凝胶对甲醇催化氧化性能的影响。结果表明,碳气凝胶的比表面积达到480 m2/g,孔径分布良好,催化剂金属颗粒较小,分散较好,循环伏安曲线图显示出Pt/碳气凝胶比传统的Pt/C对甲醇催化氧化性能高。     

The study on carbon nanotubes-supported Pt catalysts for PEMFC

Protonexchangemembranefuelcell (PEMFC)isoneofthefuelcellsdevelopedfastinrecentyears Inordertoloweritscost ,variousPt basedelectrocatalystsarepreparedtoincreasetheutilityandtoreducePtontheperunitareaoftheelectrode[1-3 ] Carbonnanotubes supportedPt (Pt/CNTs)catalystispreparedusingcar bonnanotubewithhighporosityandspecificsurfaceareaascarrierandiscomparedwithcarbon supported Pt (Pt/C)catalyst Becausecarbonnanotube (CNT )has particulardynamics ,electromagnetic ,physicalandchemicalperforman…