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SiO2-Cu2O:An efficient and recyclable heterogeneous catalyst for N-benzylation of primary and secondary amines
Silica supported copper(I) oxide Benzylation Substituted amine Recyclability Heterogeneous catalysis
2014/3/9
A mild, effective, and selective procedure is reported for the mono N-benzylation and N,N-dibenzylation of primary amines as well as mono N-benzylation of secondary amines using silica-supported coppe...
通过调节溶液的pH值,在水热条件下合成出长径比为2-45的La(OH)3纳米棒. 对水热合成过程中间体的结构演变分析,发现高碱度有利于小尺寸晶核的形成,La(OH)3晶体结构的各向异性导致这些晶种沿着C轴方向生长,进而形成纳米棒结构. 将La(OH)3纳米棒前驱体于773 K焙烧可以得到长径比为2-20的La2O2CO3纳米棒. 随着长径比的增加,La2O2CO3纳米棒暴露的(110)晶面逐渐增加...
催化氧化NO催化剂Mn/ZrO2的制备与性能研究
Mn/ZrO2催化剂 NO氧化 SCO 反应机理
2014/3/7
以二氧化锆为载体负载锰氧化物,制备了MnOx/ZrO2催化剂用于催化氧化法(SCO)脱除烟气NO,考察了制备条件和反应条件对催化剂SCO活性的影响.同时,采用N2吸附、SEM、XRD及XPS等手段对催化剂理化性质进行了表征.结果表明,采用等体积浸渍法,以硝酸锰作为前驱体制备的Mn8/ZrO2/450催化剂在300 ℃、空速15000 h-1条件下,NO转化率可达84%,表现出较好的NO氧化活性.催...
Effects of Bi and Ni on the properties of a vanadium phosphorus oxide catalyst
Vanadium phosphorus oxide catalyst Promoter n-Butane oxidation Maleic anhydride selectivity
2014/3/11
Vanadium phosphorus oxide (VPO) catalysts were synthesized by the dihydrate method which involved the two steps for the preparation of the dihydrate (VOPO4×2H2O) and the precursor hemihydrate (VOHPO4×...
Tribromo melamine as novel and versatile catalyst for the formylation and acetylation of alcohols
Tribromo melamine Acetylation Formylation Alcohol Ethyl formate Acetic anhydride
2014/3/11
Tribromo melamine has been found to be an efficient and green organocatalyst for the acetylation and formylation reactions of alcohols with acetic anhydride and ethyl formate at room temperature and u...
Low temperature adsorption of CO on modified, vicinal Cu(100) surfaces:A comparative study
Carbon monoxide Copper(100) vicinal surface Potassium modified surface
2014/3/11
The experimental results of the adsorption of CO on clean and potassium-modified vicinal Cu(100) surfaces at 125 K were present. We studied three surfaces under identical experimental conditions. At 1...
Electrocatalytic measurement of H2O2 concentration using bis(N-2-methylphenyl-salicyldenaminato)copper(Ⅱ) spiked in a carbon paste electrode
Electrochemical behavior Bis(N-2-methylphenyl-salicyldenaminato)copper(Ⅱ) complex Hydrogen peroxides Electrocatalytic reduction
2014/3/11
The electrochemical behavior of a bis(N-2-methylphenyl-salicyldenaminato)copper(Ⅱ) complex spiked in a carbon paste electrode (BMPSCu-CPE) and its electrocatalytic reduction of H2O2 were examined usin...
NaOH modified WO3/SiO2 catalysts for propylene production from 2-butene and ethylene metathesis
Propylene Olefin metathesis Tungsten trioxide Silicon dioxide Sodium hydroxide treatment Acidity Pyridine
2014/3/11
A WO3/SiO2 catalyst is used in industry to produce propylene from 2-butene and ethylene metathesis. Catalysts with various WO3 loading (4% to 10%) were prepared by impregnation and tested for the meta...
对电极在染料敏化太阳能电池(DSCs)中主要起催化氧化还原反应及收集电荷的作用,铂对电极常用的制备方法为磁控溅射法,但其成本较高,制备条件苛刻. 本文通过引入低成本的表面活性剂Span-85,所制得的铂对电极的附着力、透光率和均匀性显著改善,实现了面积可控,与两步浸泡法和旋涂热解法制备的对电极在DSCs中的光电转换效率分别为7.30%,6.96%和7.03%. 紫外-可见吸收光谱、扫描电镜和附着力...
Electrocatalysis of dopamine in the presence of uric acid and folic acid on modified carbon nanotube paste electrode
Electrocatalysis Dopamine Uric acid Folic acid Carbon nanotube Voltammetry
2014/3/9
A chemically modified carbon paste electrode (CPE), consisting of 2,2'-[(1E)-(1,2-phenylenebis(azanylylidene)] bis(methanylylidene)]bis(benzene-1,4-diol) (PBD) and multiwalled carbon nanotubes (CNTs),...
Nanocrystalline titanium dioxide catalyst for the synthesis of azlactones
Nanocrystalline titanium dioxide Electrochemical reduction method Cyclodehydration-condensation Heterogeneous catalyst
2014/3/9
Titanium dioxide nanoparticles were prepared by a electrochemical reduction method using parameters such as current density, solvent polarity, distance between electrodes, and concentration of stabili...
采用浸渍法制备了MoO3/P25催化剂(MoO3/P25(x),x为MoO3与P25质量比),用X射线衍射、紫外-可见漫反射光谱、傅里叶变换红外光谱及拉曼光谱等手段对样品进行了表征,并用催化降解亚甲基蓝考察了催化剂在可见光区的催化活性。结果表明,MoO3在P25表面最大单层负载量对应的MoO3与P25质量比在0.1左右。单层分散的氧化钼物种与P25之间有较强的相互作用,降低了P25禁带宽度,提高了...
以CuCl2为前驱物与HY分子筛进行固相离子交换制备了Cu/Y催化剂,采用热重方法研究了CuCl2与HY分子筛的表面固相离子交换反应,结合活性测试表明催化剂中高度分散的CuCl和离子交换形式的Cu+物种是甲醇氧化羰基化合成碳酸二甲酯的催化活性中心。X射线光电子能谱表征和元素分析结果表明,活性金属Cu主要以CuCl形式存在于分子筛外表面,而在分子筛笼内则以交换的Cu+和少量吸附的CuCl形式存在。与...
Thiourea dioxide: An efficient and reusable organocatalyst for the rapid one-pot synthesis of pyrano[4, 3-b]pyran derivatives in water
Pyrano[4,3-b]pyran Thiourea dioxide 4-Hydroxy-6-methylpyran-2-one One-pot synthesis
2014/3/11
A series of pyrano[4,3-b]pyran derivatives have been synthesized in excellent yields by the reaction of aromatic aldehydes with malononitrile or cyanoacetate and 4-hydroxy-6-methylpyran-2-one in water...