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991.
S. M. A. M. Bouwens D. C. Koningsberger V. H. J. De Beer S. P. A. Louwers R. Prins 《Catalysis Letters》1990,5(3):273-283
To study the local structure of the Ni promoter atom, the Ni and Mo K edge EXAFS spectra of Ni-MoS2/C hydrodesulfurization catalyst were measured in an in-situ EXAFS cell at 77 K. The Ni atom is situated in a square pyramid of five S atoms at a distance of 2.21 Å from the S atoms. In addition an EXAFS contribution due to a Mo atom at 2.82 Å from the Ni atom could be identified. This local structure indicates that the Ni atoms are situated on top of the S4 squares at the MoS2 edges in millerite-type Ni sites. The Ni atoms are situated in the planes of the Mo atoms and not in the intercalation plane midway between successive MoS2 sandwich layers. 相似文献
992.
High‐abrasion furnace black (HAF, grade N330)–filled powdered styrene butadiene rubber [P(SBR/HAF)] was prepared and the particle size distribution, mixing behavior in a laboratory mixer, and mechanical properties of P(SBR/HAF) were studied. A carbon black–rubber latex coagulation method was developed for preparing carbon black–filled free‐flowing, noncontact staining SBR powders, with particle diameter less than 0.9 mm, under the following conditions: carbon black content > 40 phr, emulsifier/carbon black ratio > 0.02, and coating resin content > 2.5 phr. Over the experimental range, the mixing torque τα of P(SBR/HAF) was not as sensitive to carbon black content and mixing temperature as that of HAF‐filled bale SBR (SBR/HAF), whereas the temperature build‐up ΔT showed little dependency on carbon black content. Compared with SBR/HAF, P(SBR/HAF) showed a 20–30% mixing energy reduction with high carbon black content (>30 phr), which confers to powdered SBR good prospects for internal mixing. Carbon black and the rubber matrix formed a macroscopic homogenization in P(SBR/HAF), and the incorporation step is not obvious in the internal mixing processing results in these special mixing behaviors of P(SBR/HAF). A novel mixing model of carbon black–filled powdered rubber, during the mixing process in an internal mixer, was proposed based on the special mixing behaviors. P(SBR/HAF) vulcanizate showed better mechanical properties than those of SBR/HAF, dependent primarily on the absence of free carbon black and a fine dispersion of filler on the rubber matrix attributed to the proper preparation conditions of noncontact staining carbon black–filled powdered SBR. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2494–2508, 2004 相似文献
993.
探索用固体废弃物———粉煤灰为主要原料作吸附剂 ,吸附处理磷酸法生产活性炭排放水中的含磷物质 ,1.5h后基本达到平衡 ,实验表明用粉煤灰处理废水中的磷物质的可行性。 相似文献
994.
995.
In order to improve the mechanical and ablation properties of 2D-carbon/carbon composites, a SiC filler was added to a 2D-preform before isothermal chemical vapor infiltration densification by using a powder infiltration technique. Backscattered electron images showed that the SiC filler was mainly concentrated between the fiber bundles and between the layers. The tensile and flexural strengths of the composites were improved by the addition of the SiC filler because of the increase of interfacial surface areas between the bundles and between the layers, the less residual open porosity, and also the strong bonding between the SiC particles and the pyrocarbon matrix. The composites with filler experienced a 15.2% lower thickness erosion rate and a 51.7% lower mass erosion rate, compared to those C/C without filler. This was attributed to the low oxygen permeability of the SiO2 shielding the exterior inter-bundle pores as well as to a thermal barrier effect. 相似文献
996.
利用Delphi和VS这两种开发平台,结合Oracle数据库,实现胶片排版、胶片调整、虚拟打印,自助打印、系统管理等功能。重点介绍了系统开发过程中针对特殊问题采用的几种技术。目的是完成胶片的集中打印管理,胶片存储备份,减少开支。 相似文献
997.
利用芬顿(Fenton)试剂的催化氧化性对焦化废水进行初步的处理,使其CODcr值除去率达80%以上,再用活性炭进行深度处理,使其CODcr值<40mg·L-1,总除去率达98%以上. 相似文献
998.
J. N. Armor 《Catalysis Letters》2007,114(3-4):115-121
Perspectives are offered for reducing the impact of huge amounts of CO2 produced today from power generation and transportation vehicles. The origins of the dilemma between the world’s increasing
use of hydrocarbons as an energy source and the cogeneration of CO2 which results as a co-product are discussed. Hydrocarbons will provide much of the fuel needs for these major, global industries
for the next 20 years and meet 60% of the world’s energy demand. With the growth of both power generation and transportation
vehicles around the world, CO2 levels will continue to increase in the atmosphere. Renewables such as wind, dams, and biomass will not be able to handle
all the energy demand. Technology breakthroughs are needed to reduce the world’s dependence on fossil fuels, which will be
aggravated by the drive to use more coal. Current approaches for removing CO2 are discussed as well as near term and future options with particular focus on how catalysis can offer some solutions. In
particular, solar photocatalysis based approaches offer a potentially viable energy solution. 相似文献
999.
该文利用多壁碳纳米管(MWCNTs)和聚(2-乙酰基-5-溴噻吩)复合纳米材料修饰电极,用于同时检测对苯二酚(HQ)、邻苯二酚(CC)和对甲苯酚(PC)。通过循环伏安法(CV),示差脉冲伏安法(DPV)和透射电镜(TEM)表征了该复合纳米材料的电化学性能和表面形貌。结果表明该电极对HQ、CC和PC具有较高的灵敏度和选择性。DPV峰电流与HQ、CC和PC的浓度在1.0×10-5~8.0×10-4mol/L,5.0×10-6~5.5×10-4mol/L和5.0×10-6~7.5×10-4mol/L范围内分别呈良好的线性关系,且检测限分别为3.0×10-6 mol/L,1.7×10-6 mol/L和2.0×10-6mol/L。 相似文献
1000.
壳聚糖的成膜性及其在食品保鲜、包装上的应用 总被引:7,自引:0,他引:7
综述了壳聚糖成膜性的影响因素,壳聚糖膜在果蔬保鲜、食品保鲜及可食性包装膜方面的应用研究进展。 相似文献