添加吐温40合成钛硅分子筛TS-1

 以自制的四丙基氢氧化铵（TPAOH）水溶液为模板剂，采用在水热晶化合成体系中添加少量非离子表面活性剂——吐温40的方法,合成了钛硅分子筛TS-1，可以明显减少TPAOH的用量，而且在一天之内，即可得到纳米尺寸的TS-1。运用XRD、TEM、BET、FT-IR及UV-Vis等表征手段考察了TS-1的结构及物理性能，并以丙烯环氧化为探针反应，考察其催化性能，得到的结果表明，用这种方法合成的TS-1样品具有较高的结晶度和较大的比表面积，晶貌呈均匀的立方体状，颗粒尺寸在100 nm左右，并且样品中含有极少量锐钛矿型TiO2，其催化丙烯环氧化反应性能较好。     

Nanometer-sized Silicon Particles Prepared by Laser Vaporization and Their Photoluminescence

Nanometer-sized silicon particles were prepared by laser vaporization of a silicon target in pure argon ambient at a reduced pressure. The shape and size of the nanoparticles were characterized by transmission electron microscopy. The as prepared nanometer silicon particles exhibit visible luminescence under light excitation and the activated light emissions are found to show a strong dependence on temperature.     

Direct Precipitation of Spinel-Type Zn(Fe, Ga)2O4 Solid Solutions from Aqueous Solutions at 90°C: Influence of Iron Valence of Starting Salt on Their Crystallite Growth

Spinel-type solid solutions in the whole range of compositions between ZnGa₂O₄ and ZnFe₂O₄ were directly precipitated as nanoparticles by dropping the starting mixed solutions of zinc sulfate, gallium sulfate, and either divalent iron chloride or trivalent iron nitrate into aqueous ammonia at 90°C. Direct precipitation of nanosized spinel-type Zn(Ga,Fe)O₄ solid solutions was also achieved by aging the mixed solutions in the presence of either urea or hexamethylenetetramine at 90°C except for one case (i.e., aging the solutions using trivalent iron salt in the presence of urea). With increased iron content in the spinel-type solid solution precipitates, their crystallite size decreased when trivalent iron salt was used, but increased when divalent iron salt was used. Change of lattice parameter a₀ of the spinel-type solid solutions was confirmed to follow the Vegard's Law.     

改性纳米二氧化钛对Pb(Ⅱ)的吸附行为研究

利用浸渍法对纳米二氧化钛进行表面改性, 制备出改性纳米二氧化钛, 用扫描电镜(SEM)对其进行了表征, 并以其为吸附剂, 以火焰原子吸收光谱法(FAAS)为分析手段, 探讨了改性纳米二氧化钛在静态吸附条件下对Pb(Ⅱ)的吸附性能, 考察了影响其吸附和解脱的主要因素及优化条件下Pb(Ⅱ)的吸附容量, 考察了常见共存离子的影响. 结果表明: 在pH 5.0下, 改性纳米二氧化钛能定量吸附Pb(Ⅱ); 1.0 mol/L HNO3作为解脱剂可使Pb(Ⅱ)定量解脱; 优化条件下Pb(Ⅱ)的静态饱和吸附容量为32.88 mg/g.     

低温陈化法制备纳米氧化锆及其机理研究

以ZrOCl2·8H2O和CO(NH2)2为原料,采用低温陈化法制得了纳米ZrO2,考察了不同反应条件,如反应物原始浓度、反应时间、不同反应物配比、表面活性剂等对产物粒径的影响,采用透射电镜、X射线衍射仪、粒度分布仪、红外光谱仪、差热分析仪对产品进行了表征,并得出结论:低温陈化法可以制得纳米级的ZrO2粒子,而且粒子分散性、均匀性较好,并对其机理进行了探讨.     

Synthesis and Luminescent Properties of Novel Nanometer-sized ScAlMgO_4：Eu~（3＋） Phosphors for PDP

Novel nanometer-sized ScAlMgO4:Eu3+ phosphors were successfully synthesized by the citric acid complexation method.The mean particle size of the obtained powders was within the range of 100～150 nm according to the SEM patterns.In ScAlMgO4:Eu3+ showed strong characteristic red emission,of which the maximum emission peak was located at 629 nm for ultraviolet(UV) excitation.The dependence of photoluminescence intensity on Eu3+ concentration was also studied in detail,and the emission intensity of Sc1-xEuxAlMgO4 was about 10% at optimized Eu3+ concentration.Furthermore,the luminescence decay measurements showed that the lifetimes of Eu3+ were in the range of millisecond.The obtained ScAlMgO4:Eu3+ phosphors with nanometer size and excellent luminescence efficiency would be potential red phosphors in plasma display panels.     

纳米氧化锌的合成与表征

纳米氧化锌的合成与表征何勇宁，沈孝良，马礼敦（复旦大学分析测试中心上海２００４３３）关键词纳米材料，氧化锌，合成，表征制备纳米材料的方法很多，如蒸发冷凝法、化学气相沉积法、溶胶－凝胶法、超临界法、水热法及各种热分解法等。Ｌｉｕ等［２］用超声雾化热分解...     

溶胶－凝胶法制备高比表面积的纳米氧化铝及其对过渡金属离子吸附行为的研究

溶胶－凝胶法合成高比表面积纳米氧化铝，以透射电镜（TEM），X射线衍射（ XRD），比表面积测定（BET）等手段对所得的纳米氧化铝进行了表征，表明纳米粒 子的粒径在40－80nm。以ICP－AES为检测手段，考察了纳米氧化铝材料在静态吸附 条件下对于过渡金属离子的富集分离性能。结果表明，在pH8-9范围内，过渡金属 离子Cu,Mn,Cr,Ni可实现定量分离富集。吸附于纳米氧化铝上的金属离子可用1. 0mol/L盐酸溶液完全解脱。将所合成的纳米氧化铝用于实际标准样品黑麦叶和煤烟 灰中Cu,Mn,Cr,Ni的分离富集及ICP－AES测定，结果满意。     

纳米PbS的合成新方法——一步室温固相化学反应法

纳米ＰｂＳ的合成新方法———一步室温固相化学反应法俞建群１贾殿赠１张校刚１夏熙１郑毓峰２（１新疆大学化学系，乌鲁木齐，８３００４６）（２新疆大学物理系，乌鲁木齐，８３００４６）关键词纳米；硫化铅；固相化学反应当前，合成化学的研究热点在于合成方法的不...