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排序方式: 共有367条查询结果,搜索用时 31 毫秒
31.
George W. Mushrush John M. Watkins Robert N. Hazlett Dennis R. Hardy Bruce H. Black 《Petroleum Science and Technology》2013,31(7):753-767
ABSTRACT Instability problems in both shale and petroleum derived middle distillate jet fuels have been correlated with the presence of peroxidic species. Although a good body of knowledge exists concerning the formation of peroxides in the liquid phase, relatively little is known about the reaction/ decomposition pathways available when other functional groups are present, since sulfur is the most abundant heteroatam present in jet fuels, the reaction of t-butyl hydroperoxide (tBKP) and/or oxygen with thiophenol in the presence of the active olefin, styrene, was examined in deaerated benzene at 120°C. The complex product mixture was analyzed by combined capillary column GC/MS. Major products included acetone, t-butanol and isdbutylene from the tBHP. Thiophenol and styrene combined to form addition products. Phenyl disulfide was observed from the thiophenol. The results indicated that although the product slate was complex, it was possible to explain the product mix in terms of a few competing reactions. 相似文献
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通过生产性试验,探讨了氯化消毒过程对水中有机物及水的致突变活性的影响规律。结果表明,氯化消毒致使自来水中的次生有机物种类和浓度明显增加,水中除了产生卤代有机物外,还生成了多种其它有机物,如酮、酯等类有机物。 相似文献
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Thermal conductivity of normal pentane in the temperature range 306–360 K at pressures up to 0.5 GPa
This paper reports the results of new, absolute measurements of the thermal conductivity of normal pentane in the temperature range 306 to 360 K at pressures up to 0.50 GPa. The experimental data have an estimated uncertainty of ±0.3%. The density dependence of the thermal conductivity along all of the isotherms cannot be represented by a common equation within its estimated uncertainty. Nevertheless, such a universal equation does provide a simple method of correlating the complete set of data with an error of no more than ±2.5%. 相似文献
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Microporous and mesoporous materials with isolated vanadium species as selective catalysts in the gas phase oxidation reactions 总被引:1,自引:0,他引:1
The preparation of V-containing micro- and mesoporous (silicates, aluminosilicates and aluminophosphates) materials as well as the nature of V species incorporated in framework positions is reviewed. In addition, the catalytic performance of V-silicalite, VAPO-5 and V-MCM-41 in the gas phase selective oxidation of hydrocarbons has also been compared. 相似文献
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In the leek moth, Acrolepiopsis assectella, the male, stimulated by a calling female, produces a sexual pheromone that is active on the female. The male-produced pheromone blend contains eight alkanes previously isolated from the male hair-pencils. We used EAG techniques to study the effect of the pheromone on females reared on leek or on artificial diet and on males reared on leek. The optimal stimulation duration appeared to be 1.6 sec exposure to the pheromone or components. The concentrations tested on the antenna were of the order of 1012 molecules/cm3. The hair-pencil extract tested was of an estimated concentration of around 109 molecules/cm3. The antennal responses are expressed relative to responses to a standard, amyl acetate, but also as an absolute value. Generally, females reared on artificial diet and males reared on leek responded better than females reared on leek. Of the alkanes tested, those present in hair-pencils gave higher responses, with hexadecane always giving the strongest response. A possible inhibiting activity of male leek moth pheromone on the sexual behavior of conspecific males was investigated. The behavior of sexually stimulated males was observed in the presence of other males, hair-pencil extracts, and different compounds either pure or in a mixture. The experiments established that in this species, male pheromone inhibits wing fluttering duration of conspecific males. This inhibition was obtained not only with fluttering males as a source of pheromone but also with all the alkanes tested. The inhibition was due to hair-pencil chemicals, particularly if these were perceived by olfaction plus contact. Wing fluttering increased the inhibitory activity of male-derived alkanes. 相似文献
37.
A Phytochemical–Halogenated Quinoline Combination Therapy Strategy for the Treatment of Pathogenic Bacteria
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Prof. Robert W. Huigens III 《ChemMedChem》2015,10(7):1157-1162
With the continued rise of drug‐resistant bacterial infections coupled with the current discouraging state of the antibiotic pipeline, the need for new antibacterial agents that operate through unique mechanisms compared with conventional antibiotics and work in synergy with other agents is at an all‐time high. We have discovered that gallic acid, a plant‐derived phytochemical, dramatically potentiates the antibacterial activities of several halogenated quinolines (up to 11 800‐fold potentiation against Staphylococcus aureus) against pathogenic bacteria, including drug‐resistant clinical isolates. S. aureus demonstrated the highest sensitivity towards gallic acid–halogenated quinoline combinations, including one halogenated quinoline that demonstrated potentiation of biofilm eradication activity against a methicillin‐resistant S. aureus (MRSA) clinical isolate. During our studies, we also demonstrated that these halogenated quionlines operate through an interesting metal(II) cation‐dependent mechanism and display promising mammalian cytotoxicity. 相似文献
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将一个饱和液体状态方程(TONG方程)应用于已知的双元液体混合物密度的推算,温度为105K~140K,该混合物的组分是低碳烷烃和氮,它们都是液化天然气(LNG)的主要成分。此模型方程利用纯组分数据来预测液化天然气低温下密度而被检验。本方法的优点是使用简便。 相似文献