共查询到20条相似文献,搜索用时 11 毫秒
1.
Mahmud Diab Michael Volokh Brian Moshofsky Ilan Jen-La Plante Kobi Flomin Elina Chockler Taleb Mokari 《Israel journal of chemistry》2012,52(11-12):1081-1089
The synthesis of various types of metal oxide and metal sulfide nanostructures through the thermal decomposition of single-source molecular precursors is presented. By varying the reaction conditions, such as solvent, precursor concentration, temperature, and time, we were able to control the shape of Fe3O4 (rectangles and belt-like structures), CoO nanofibers, and SnO2 nanowires. Two sulfides are also presented: CdS filling a vertically aligned ZnO nanowire array (to create a hybrid structure) and SnS wires. The formation of various phases of iron oxide and cobalt oxide is also shown. 相似文献
2.
简要介绍了用于吸附水体重金属的几种纳米金属氧化物,包括:纳米铁氧化物、纳米锰氧化物、纳米铝氧化物、纳米钛氧化物、纳米锌氧化物、纳米镁氧化物、纳米铈氧化物以及纳米金属氧化物复合材料,讨论了各种纳米金属氧化物处理水体重金属的优缺点,并展望了其应用前景。 相似文献
3.
4.
晶态介孔金属氧化物的合成研究进展 总被引:1,自引:0,他引:1
晶态介孔金属氧化物与相应的无定形材料相比具有更加优异的催化、光学、电学、磁学和力学等性能,具有较宽的应用范围,是近年来介孔材料合成的热点。本文主要对晶态介孔金属氧化物的制备方法,包括非晶晶化法、蒸发诱导自组装法和硬模板法进行了介绍,并对这些方法的优缺点进行了比较。 相似文献
5.
6.
钢渣中二价金属氧化物固溶体的选别性研究 总被引:1,自引:0,他引:1
为了解决钢渣活性低、在水泥生产中难以利用的问题,探索分选出RO相(二价金属氧化物固溶体)惰性矿物的可能性。测定两种钢渣的岩相特征,探明RO相及伴生矿物的力学性质、比磁化率和比电阻,并通过分选钢渣粉料实验进行验证。结果表明:钢渣中RO相含量为20%~30%,平均粒径为31~45μm; RO相是钢渣中密度、硬度最大的矿物,在粗粒级和重组分中富集,气力分选粗粉中RO相含量是细粉的2.3倍;RO相属于中磁性矿物,伴生矿物属于非磁性矿物,在中等磁场磁选中能分选回收;伴生矿物为非导体矿物,RO相为导体矿物或中等导体矿物能用电选回收。RO相中FeO/MgO的摩尔比越高对三种分选越有利;氧化焙烧钢渣有利于磁选而不利于电选。 相似文献
7.
More acidic sulfated metal oxides (SMO) such as SO4
2-/ZrO2 and SO4
2-/TiO2 catalyzed the methoxymethylation of alcohols with dimethoxymethane at ambient temperature to achieve a product yield of greater than 90% within a few hours. The reaction displayed a significant steric effect on the product yield with a preferential order of primary alcohol > secondary alcohol tertiary alcohol. The observed steric effect might result from the repulsion between the bulky alkyl group in the alcohol and the two methoxy groups in the protonated dimethoxymethane (oxonium ion). 相似文献
8.
9.
10.
11.
12.
金属氧化物催化环己基苯过氧化反应的研究 总被引:1,自引:0,他引:1
环己基苯的过氧化是环己基苯法生产苯酚、环己酮工艺中最重要的一步反应。该文考察了4种金属氧化物对环己基苯过氧化反应的催化活性,反应温度383 K时,以环己基苯转化率为指标,4种催化剂活性大小顺序为:MnO2CuOCaOZnO。研究了以MnO2为催化剂时反应温度和催化剂用量等不同因素对环己基苯催化过氧化反应的影响,得出了优化的反应条件为:常压,反应温度393 K,催化剂用量0.01 g,通氧速率100 mL/min,反应时间10 h,在该条件下,环己基苯的转化率和过氧化氢环己基苯的选择性分别为33.58%和80.09%。 相似文献
13.
14.
环糊精由于其具有特殊的分子空腔结构,可以增容及解吸吸附在土壤中的有机污染物,并对土壤表层的有机污染物具有一定的光解促进作用,通过对环糊精改性还能达到同时去除土壤中有机物和重金属污染物的效果。目前环糊精作为环境友好型材料已经广泛的应用于环境治理中,文章介绍了环糊精及其衍生物在污染土壤修复方面的应用。 相似文献
15.
16.
17.
18.
《分离科学与技术》2012,47(5):729-741
Chelating PS-EDTA resins modified by metal (Fe, Al, and Zr) oxides were used as adsorbents to remove Hg(II) from aqueous solutions. The modified resins were characterized by BET, FTIR, and XPS. The amino, carboxylate, and the metal oxides on resins exhibited a synergistic effect for Hg(II) removal. It was observed that the modification of PS-EDTA resin not only increased the adsorption of Hg(II) but also accelerated the adsorption rate of Hg(II). The equilibrium data of Hg(II) were best described by the Freundlich isotherm, and the kinetics were found to follow the pseudo-second-order kinetic model. Also, thermodynamic parameters showed that Hg(II) adsorption was endothermic and spontaneous in nature. The increasing the concentration (0.1–2.0 g/L) of NaNO3 in Hg(II) solution did not affect the adsorption of Hg(II). Moreover, the competitive adsorption indicated that the modified resins had higher selectivity towards Hg(II) over Cd(II), Pb(II), Zn(II), or Cu(II) in a binary system. All of the above results indicated that the modified resin was an efficient and reusable adsorbent for Hg(II) removal due to its simple preparation, high adsorption capacity, fast adsorption rate, ionic strength independence, high selectivity, and good reusability. These properties are of potential application in the fixed-bed continuous-flow column for Hg(II) removal from wastewaters. 相似文献
19.
热解析技术是一种针对去除污染场地中的挥发性和半挥发性有机污染物快速而高效的环境修复技术.本文扼要探讨了该工艺的技术原理、工艺路线、应用前景和存在的问题. 相似文献
20.
氧化物、复合氧化物的制备 总被引:1,自引:0,他引:1
氧化物、复合氧化物作为无机功能陶瓷材料已引起世人注目。系统地介绍了固相法、气相法、共沉淀法、冷冻干燥法、溶胶-凝胶法、水溶液电解法、高压法、水热法等合成氧化物、复合氧化物的方法及其优缺点。 相似文献