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991.
应用注蒸汽开采稠油中的水热裂解反应及稠油的降粘机理,将它应用到稠油集输过程中,通过实验找出较好的催化剂,从当中得出一些结论,可能被油田使用。  相似文献   
992.
水蒸气蒸馏法提取广西百色地区迷迭香茎、叶中的挥发油,利用GC-MS联用仪进行了分析。共分离出36个峰,鉴定了其中31个化学成分,占总含量的97.08%。其主要成分为1,8-桉叶素、α-蒎烯、樟脑、莰烯、α-松油醇、乙酸龙脑酯及龙脑等。  相似文献   
993.
The process of grinding soybeans to a fine flour and extracting the flour with hexane was studied on a pilot plant scale. The crude oil from the pilot plant study had 15 ppm phosphorus and was suitable for physical refining after a light acid pretreatment and bleaching. The refined oil showed a Lovibond color of 1.4 yellow and 0.3 red. The pilot plant study also showed that grinding of the soybeans and the separation of solid from miscella were the most difficult steps in solvent extraction with fine flour. A laboratory study on separation of miscella from meal by aqueous ethanol reduced the hold-up volume, but it did not remove all the miscella. A test with betacarotene showed that only the miscella outside the flour particles was displaced. Aqueous ethanol solutions used as a second solvent extracted additional nontriglyceride materials (primarily phospholipids) from the meal. Also, the free fatty acid content of the oil was increased with aqueous ethanol solution wash. The quality of the extracted crude oil was lowered by using a second solvent, but it had the advantage of needing only one centrifugation to separate miscella from meal.  相似文献   
994.
采用GC—MS联用技术首次分析了蒲葵根中脂肪油的组成,共分离出36个峰,并鉴定出其中的23种化合物。该脂肪油的主要成分为月桂酸乙酯、十六烷酸乙酯、亚麻酸、亚油酸乙酯、9—十八碳烯酸乙酯等。为蒲葵根资源的开发利用提供了科学依据。  相似文献   
995.
本文介绍了一种新型的能在较高压力环境下进行细过滤的PE井口高压滤芯的结构特征、关键技术研究、技术特性,以及应用效果。  相似文献   
996.
Tocopherols are natural antioxidants that increase the stability of fat-containing foods and perform important biological activities. Significant variations (389 to 1873 μg g oil−1) in the total tocopherol concentration of sunflower seed oil have been reported. The main objectives of this work were to determine the influence of intercepted photosynthetically active radiation on tocopherol concentration during seed filling and to establish and validate relationships between tocopherol concentration in oil and other quality variables of the seed. Seven sunflower hybrids were grown under good water and nutritional conditions in two similar experiments carried out in two contrasting environments. Treatments were applied to modify the amount of radiation intercepted per plant during seed filling in order to obtain a range in oil yield per plant and its components. Greater per plant intercepted radiation decreased the tocopherol concentration in oil. Tocopherol concentration decreased when oil weight per seed increased. Tocopherol concentration stabilized for oil weight per seed higher than 23 mg oil seed−1. This exponential relationship accounted for 73% of the variability in tocopherol concentration (507 to 1203 μg g oil−1) despite differences in hull type, locations, hybrids, and radiation treatments. The proposed relationship acceptably predicted independent results. Crop management techniques could lead to seeds with greater concentrations of tocopherols.  相似文献   
997.
稠油化学降粘方法研究进展   总被引:3,自引:0,他引:3  
综述稠油化学降粘方法(井下水热催化裂化降粘、表面活性剂降粘、油溶性降粘剂降粘、降凝剂降粘)的研究与应用,阐述了这些化学降粘技术作用机理和存在的问题,指出降粘剂的发展趋势。  相似文献   
998.
Rice bran oil containing 30–50% free fatty acid was continually converted to an oil containing more than 75% of triacylglycerol (TG) by means of immobilized lipase. The reaction was carried out at 60°C for 24 h with dehydration and reactant mixing by dry nitrogen flow under a positive nitrogen atmosphere. Enzymatic TG synthesis with evaporation by heating was not suitable because of the increasing peroxide value of the oil. Part of this article was presented at the annual meeting of the Japan Oil Chemists' Society at Sendai, Japan, October, 16, 1990.  相似文献   
999.
Microemulsions with a palm oil-based emollient, i.e., medium-chain triglyceride (MCT), and water or glycerol, stabilized by two oppositely charged ionic surfactants and a medium-chain alcohol, were investigated. The results showed that only the water-in-MCT or the glycerol-in-MCT microemulsions were prominent. The maximum solubilization of the MCT emollient was higher in cetyltrimethyl ammonium bromide, i.e., the positively charged surfactant that contained a nitrogen atom, than the negatively charged surfactant sodium dodecyl sulfate. However, the results did not lend themselves for selecting any decisive factor that would explain the different solubilization behavior encountered in the investigated aqueous and nonaqueous systems.  相似文献   
1000.
Abdul Majid  Bryan D. Sparks 《Fuel》1983,62(7):772-774
The application of a low temperature ashing method for estimating total residual organic matter (toluene insolubles) in oil sands is described. A linear correlation exists between organic carbon content and loss on ignition at 400 ± 10 °C of solvent extracted oil sands. The ratio between total organic carbon and the weight loss on ignition (CT/LOl) owing to the removal of residual organic matter is much lower than that obtained for toluene soluble bitumen fractions, indicating very different chemical composition for the residual organic matter. The measured carbon content of the residual organic matter in oil sands suggests that this material could be a mixture of various fractions contained in resins, asphaltenes, asphaltic acids and humic acids.  相似文献   
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