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91.
Chinese Maoming (Guangdong Province) oil shale was subjected to supercritical fluid extraction with water and toluene, respectively,
in a batch autoclave. Yields of organic matter were greater with toluene than with water, and more organic compounds of high
molecular weight were extracted with toluene than with water, although the weight losses of the oil shale with toluene and
water were almost the same. Yield distributions ofn-alkanes were also almost the same, irrespective of the solvent.
This paper is dedicated to Dr L K Doraiswamy on his sixtieth birthday. 相似文献
92.
采用一步水热合成法,在180℃,12 h条件下制备了30%二氧化锰/石墨烯(MnO2/G)复合材料。实验结果表明:MnO2均匀且较为牢固地锚定于石墨烯表面,同时MnO2的沉积阻止了多层石墨烯的复合,从而使得复合物具有较大的比表面积。相同条件下,MnO2/石墨烯相较于单纯MnO2或石墨烯具有很好的臭氧催化氧化甲苯性能,这可以归结于MnO2和石墨烯间的协同催化作用。 相似文献
93.
利用固体废弃物矾土矿尾矿制备催化剂载体,采用浸渍法将氧化物活性组分载于催化剂载体,对甲苯催化燃烧进行了研究。实验结果表明:以矾土矿尾矿制备的催化剂载体,所选4种单一活性组分中,催化效果较好的为Mn/Zr O2和Cu/Zr O2整体催化剂,其负载14%Mn/Zr O2整体催化剂在260℃时转化率为47%,负载16%Cu/Zr O2整体催化剂在300℃时转化率为49%,均接近起燃温度。 相似文献
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98.
纸品粘结用聚氨酯热熔胶的制备 总被引:1,自引:0,他引:1
采用不同相对分子质量的聚乙二醇(PEG)和甲苯二异氰酸酯(TDI)为原料制备了水溶性聚氨酯热熔胶。讨论了PEG相对分子质量、原料配比、TDI滴加温度、反应时间等对产品性能的影响。结果表明,当PEG8000∶PEG600∶TDI摩尔比为1∶1∶2.28、TDI滴加温度为60~70℃、反应时间为3h时,所得聚氨酯热熔胶软化点为72.5℃、剪切强度为2.668MPa、吸湿率为0.81%,胶丝水溶性优,适用于纸品的粘接,并有利于废纸的回收处理。 相似文献
99.
Several dietary and host related factors potentially influencing carotenoid (beta-carotene, lutein and zeaxanthin) bioaccessibility from spinach, including different concentrations of sodium, calcium and magnesium, were systematically investigated by means of an in vitro digestion model. Bioaccessibility was highest when milk (4% fat) and lowest when skimmed milk or more complex food matrices such as sausage were added to the meal. Micellarisation significantly depended on the presence and concentration of bile salts and pancreatin (p < 0.001, Bonferroni) but was unaffected by pepsin. Micellarisation significantly decreased to 61.4 ± 3.0% of control (p < 0.001, Dunnett’s) at high cholesterol (114 mg/test meal) but not at similar stigmasterol concentrations. Calcium and magnesium ?13.8 mM individually inhibited micelle formation ( >40% on average), presumably due to the generation of insoluble soaps with fatty acids and bile salts. Increased sodium concentrations (280 and 460 mM) altered carotenoid micellarisation patterns, favoring beta-carotene isomers (p < 0.001, Bonferroni) but decreasing lutein and zeaxanthin (p < 0.001 and p < 0.05, respectively, Bonferroni). This study suggests that minerals may impact carotenoid bioavailability. 相似文献
100.
Robert L. Burns 《Journal of surfactants and detergents》1999,2(1):13-16
Alkylbenzene sulfonates based on toluene, xylene and cumene, and alkylnaphthalene sulfonates act as hydrotropes in surfactant
systems. One measure of hydrotropicity is the amount of hydrotrope required to clear a cloudy detergent formulation; some
hydrotropes are more effective than others, depending on the surfactant formulation. Another measure is the modification of
the viscosity of surfactant formulations; the change in the viscosity depends on the amount and type of hydrotrope used and
on the specific formulation involved. Additionally, alkylnaphthalene sulfonate hydrotropes change the solubility of nonionic
surfactants in water, and both types of hydrotrope raise the cloud point of nonionic surfactant solutions; however, the naphthalene-based
hydrotropes are more efficient. Ross-Miles foam test data are used to compare the foam characteristics of different alkylnaphthalene
sulfonates. A critical micelle concentration (CMC) was determined for the alkylnaphthalene sulfonates, but although alkylbenzene
sulfonates do show some surface activity, a CMC could not be found for these materials.
Presented as a poster session at the AOCS Annual Meeting & Expo, May 1997, Seattle, Washington, and at Soaps, Detergents,
and Oleochemicals: An AOCS International Conference, October 1997, Fort Lauderdale, Florida. 相似文献