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101.
J. A. Azizi D. Dollimore P. J. Dollimore G. R. Heal P. Manley W. A. Kneller W. Jin Yong 《Journal of Thermal Analysis and Calorimetry》1993,40(2):831-847
In this study a relationship between the surface and textural properties of carbon blacks and the gasification process induced thermally in air is noted. A temperature jump method was used to follow the gasification in air and to establish the relevant Arrhenius parameters. This can be associated with the activity of ‘basal’ plane carbon atoms as well as ‘edge’ carbon atoms at the surface. This is based on a model of carbon black structure consisting of the irregular packing of small graphite carbon structures. The carbon black surface was measured using a single measurement of adsorption based essentially on the BET volumetric method. The carbon black surface had a rate of oxidation per unit are which clearly indicated that the lower area carbon blacks had a predominately active area of ‘edge’ atoms at the surface while the surface of the higher area carbon blacks had a predominate amount of ‘basal’ plane graphite carbon atoms. 相似文献
102.
选择性氧化含氰基的对硝基苯硫醚 总被引:2,自引:0,他引:2
选择性氧化含氰基的对硝基苯硫醚岳国仁,王建华,张正(南京大学化学系南京210008)关键词含氰基硫醚,选择性氧化,四水合过硼酸钠据报道[1]对硝基苯磺酰基乙腈的合成,反应时间长,可采用四水合过硼酸钠(NaBO3·4H2O)作为氧化剂,受到重视[2,3... 相似文献
103.
104.
油莱甾醇内酯(Brassinolide)(1)是一种高效的植物生长激素,其生理活性与侧链中C_(22)、C_(23)的构型密切相关。当C_(22)、C_(23)为S、S构型时,其活性仅为1的十分之一。在1的 相似文献
105.
Mohammad ILYAS Mohammad SADIQ Imdad KHAN 《催化学报》2007,28(5):413-416
采用一种环境友好的方法,以分子氧为氧化剂,以ZrO2为催化剂,在无溶剂的条件下实现了醇的选择性氧化.苯甲醛、环己酮和辛醛等是相应醇的主要氧化产物.考察了不同反应条件(搅拌速度、反应时间和温度)、催化剂制备参数(焙烧温度和负载量)及氧分压等的影响.结果发现,对于醇氧化生成相应羰基化合物,1 223 K焙烧的ZrO2比723 K焙烧的ZrO2显示出更高的催化活性.催化剂在反应混合物中不溶解,可以通过简单的过滤使其分离并重复使用.当搅拌速度大于900 r/min时,对醇的转化速率无明显的影响. 相似文献
106.
采用电沉积-热解法在3Cr25Ni7N合金表面制备了Y2O3薄膜,并研究了薄膜处理对合金在1000℃空气中的抗高温氧化性能的影响。氧化动力学曲线、SEM及XRD分析结果表明,Y2O3薄膜处理使合金表面氧化膜以尖晶石结构为主,氧化膜致密,有效地抑制了Cr2O3的挥发反应,且氧化膜与基体的附着性好,因此合金在高温下的抗氧化性能得到提高,这与氧化钇薄膜在较低温度下抗高温氧化性能提高的机制是不同的。在不同温度下,Y2O3薄膜处理均可以有效提高合金的抗高温氧化性能。 相似文献
107.
The gas-phase photocatalytic oxidation of aniline on a new kind of porous nano-TiO2 composite films is investigated. The composite film was prepared on glass fiber with the water glass as binders and dilute
H2SO4 solution as solidifying reagent. The surface characters were observed by scanning electron microscope. The photocatalytic
degradation of aniline on the composite films was carried out in a TiO2/UV system. Some important factors affecting the photodegradation, such as the concentration of TiO2, the initial concentration of aniline, and the existing water vapor, are also studied. The product of photocatalytic oxidation
was detected by Fourier transform-Infrared. The partial intermediate products were absorbed on TiO2 surface, which resulted in catalyst deactivation. But when it was irradiated under UV illumination or solar irradiation for
some time, the catalyst could be reused without loss of catalytic activity.
Translated from the Journal of Wuhan University (Natural Science Edition), 2005, 51(2) (in Chinese) 相似文献
108.
Takato Mitsudome 《Tetrahedron letters》2006,47(9):1425-1428
Palladium-montmorillonite was proven to be highly efficient for the Wacker oxidation of terminal olefins to the corresponding methyl ketones. The catalyst was reusable while maintaining high activity and selectivity. 相似文献
109.
110.
The polystyrene supported phenylalanine Schiff base complex of Mn(Ⅱ)(PS-Sal-Phe-Mn)was prepared with chloromethylated styrene polymer beads, 2,4-dihydroxybenzaldehyde,L-phenylalanine and manganese(Ⅱ)acetate tetrahyrate., The polymeric ligand and the complex were characterized by FT-IR,, small area X-ray photoelectron spectroscopy(XPS), and ICP-AES. In the presence of the manganese complex, cyclohexene(1)was effectively oxidized by molecular oxygen without reductant. The major products of the reaction were 2-cyclohexen-1-ol(2),2-cyclohexen-1-one(3)and 2-cyclohexen-1- hydroperoxide(4), which was different with typical oxidation of cyclohexene. The influence of reaction temperature and additive for oxidation had been studied. The selectivity of 2-cyclohexen-l-hydroperoxide varied with reaction time and different additives. The mechanism of cyclohexene oxidation had also been discussed. 相似文献