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101.
Solvent assisted spreading of CoO over monolayer MoO3/Al2O3 catalysts has been studied. CoCO3 · Co(OH)2 and CoCO3 reacted with MoO3/Al2O3 in water slurries. CoO deposition over MoO3/Al2O3 extrudates was followed by EPMA. In the set of eleven MoO3/Al2O3 catalysts, the amount of CoO adsorbed was roughly proportional to the surface area of MoO3 monolayer. The adsorbed Co species efficiently enhanced the HDS activity. 相似文献
102.
深入阐述了牙膏增稠的流变学理论,同时,介绍了用于生产牙膏的儿种主要增稠剂的性能及其在牙膏配方中的应用。流变学理论和黏合剂化学技术的有机结合直接导致了新型牙膏配方产品的诞生。 相似文献
103.
The Pennsylvania State University is researching an advanced oxidation system, which includes an air-phase photolytic chamber, an air/water stripping tower, and granular activated carbon (GAC) beds, for controlling volatile organic compounds (VOCs).A laboratory-scale experimental procedure has been employed that simulated certain aspects of several full-scale installations. The apparatus has been used to characterize the loading capacity and mass transfer zone of selected VOCs on coconut shell GAC. The GAC bed has then been placed in series with an ultraviolet reactor, which generates ozone and advanced oxidants in order to regenerate the loaded GAC at intensities of advanced oxidants that were higher than full-scale installations.VOC loading tests revealed that the adsorption of methyl isobutyl ketone (MIBK) was characterized by a well-defined mass transfer zone. Upon exposure to UV/O3, desorption and/or destruction of the MIBK and other VOCs occurred most prominently within the first inch of the GAC bed. This correlated with the penetration of advanced oxidants into the GAC bed, which also occurred most significantly in the bed's first inch. However, the amount of oxidant penetration increased with time. The removal of oxidants from air by GAC was accompanied by a decrease in mass of the GAC. The ability of oxidants to penetrate a GAC bed was altered when the bed was loaded with a VOC. 相似文献
104.
105.
简要介绍了氟化学的发展历史,结合绿色化学和绿色合成技术,介绍了氟化学、全氟溶剂、氟两相体系和氟代催化剂的概念,特性,对氟两相体系在有机合成和催化反应中的应用以及研究进展作了综述。 相似文献
106.
M.?NaczkEmail author R.?B.?Pegg R.?Zadernowski F.?Shahidi 《Journal of the American Oil Chemists' Society》2005,82(4):255-260
Possible use of canola hulls as a source of natural anti-oxidants was explored. Cyclone canola hulls were extracted with methanol
(30 to 80%, vol/vol) and acetone (30 to 80%, vol/vol). The free radical-scavenging activity of phenolic extracts so prepared
was evaluated using the 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) radical ion (ABTSo−), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, and chemiluminescence assays. The total content of phenolics in prepared
extracts from canola hulls ranged from 15 to 136 mg sinapic acid equivalents per gram of extract. Higher levels of condensed
tannins were detected in the acetone extracts than in the corresponding methanolic counterparts. Seventy and 80% (vol/vol)
acetone extracts displayed markedly stronger antioxidant activity than any of the other extracts investigated. Statistically
significant linear correlations were found between TEAC (Trolox equivalent antioxidant capacity) values (expressed in mM of
Trolox equivalents per gram of extract) and total pehnolics, TEAC and total condensed tannins (i.e., determined using the
modified vanillin and pronthocyanidin assays), as well as TEAC and protein precipitation activity of phenolic extracts (i.e.,
measured using the dye-labeled assay). The antioxidant activities of extracts as determined by the ABTSo− radical ion assay correlated highly with those of the chemiluminescence and DPPH radical assays. 相似文献
107.
酚醛环氧乙烯酯树脂研究 总被引:2,自引:0,他引:2
梁辉 《玻璃钢/复合材料》2002,(2):41-43
本文以酚醛环氧树脂F-51与甲基丙烯酸合成出酚醛环氧乙烯酯树脂,并对此树脂的耐热性、耐化学溶剂性能进行了研究. 相似文献
108.
Pitt William R.; Goodfellow Julia M. 《Protein engineering, design & selection : PEDS》1991,4(5):531-537
Previous analysis of the distribution of experimental solventmolecule positions around amino acid side chains showed thatdistinct clustering occurred close to polar or charged atomsin proteins. We have used those data to predict likely solventpositions around proteins not used in our initial analysis.We envisage that this algorithm, AQUARIUS, will be useful forfinding solvent positions in electron density maps generatedby protein crystallography and as useful starting positionsfor solvent molecules in computer simulation studies of macromolecules. 相似文献
109.
110.