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991.
利用红外光谱法、气相色谱法(GC)和色-质联用(GC-MS)技术分析测定了投运一年后的劣质变压器油中硅胶吸附物的呈色成分,分析了硅胶吸附变色的原因。 相似文献
992.
T. V. Chernenko A. I. Glushenkova A. M. Nigmatullaev 《Chemistry of Natural Compounds》2002,38(4):307-309
Lipids from Mediasia macrophylla leaves were studied. Classes of neutral, glyco-, and phospholipids and their fatty-acid composition were determined. The content of chlorophyll and carotinoid pigments in the leaves and lipid extract was found. Essential oil was isolated by steam distillation and contained free and bound fatty acids. 相似文献
993.
994.
Cao X Li Y Jiang S Sun H Cagna A Dou L 《Journal of colloid and interface science》2004,270(2):295-298
Viscoelastic properties of two polymers, partially hydrolyzed polyacrylamide and partially hydrolyzed modified polyacrylamide, widely used in chemical flooding in the petroleum industry, were investigated at three interfaces, water-air, water-dodecane, and water-crude oil, by means of a dilational method provided by I.T. Concept, France, at 85 degrees C. Polymer solutions were prepared in brine with 10,000 mg/l sodium chloride and 2000 mg/l calcium chloride. It has been shown that the viscoelastic modulus increases with the increment of polymer concentration in the range of 0-1500 mg/l at the water-air interface. Each polymer shows different viscoelatic behavior at different interfaces. Generally speaking, values of the viscoelastic modulus (E), the real part (E'), and the imaginary part (E") at the crude oil-water interface for each polymer are lower than at the air-water or water-dodecane interface. The two polymers display different interfacial properties at the same interface. Polymer No. 2 gives more viscous interfaces than polymer No. 1. All the information obtained from this paper will be helpful in understanding the interfacial rheology of ultra-high-molecular-weight polymer solutions. 相似文献
995.
996.
中性载体ETH1616推动质子在油/水界面的转移 总被引:1,自引:0,他引:1
本文用循环伏安法和循环电流扫描计时电位法研究了中性载体ETH1616(N,N-bjs-heptylethyldiamide)推动质子在油/水界面的转移过程,探讨了有关转移过程的机理,测定了相应的扩散系数和配合物的稳定常数。 相似文献
997.
本文研究了我国37种原油、机油和柴油的荧光激发光谱和发射光谱特征。提出用比值法或发射波长法将矿物油分组,尔后选择相应的标准油。该法克服了统一方法制取标准油烦琐、费时的缺点。 相似文献
998.
High pressure thermogravimetric analysis (HPTG) was used in order to study the oxidation of crude oil in a porous medium under pressurised conditions for simulation of in-situ combustion during oil recovery. Three distinct reaction regions were observed from the HPTG curves in an oxidising environment subjected to a constant heating rate. These were low temperature oxidation, fuel deposition and high temperature oxidation. The method of Coats and Redfern was used to obtain kinetic parameters and the results are discussed.The authors would like to express their appreciation for the financial support of TUBITAK (The Scientific and Technical Research Council of Turkey) and the Royal Society. 相似文献
999.
1000.
《Arabian Journal of Chemistry》2022,15(11):104189
The quality of grains is influenced by storage pests, which are not only spoilers of stored grain, but also vectors of human and animal diseases. Chemical pesticides play an essential role in the cultivation and storage of cereals, however, due to the low degradability and residual toxicity of synthetic pesticides on the environment and non-target organisms, as well as the increasing resistance of target organisms to them, consideration should be given to the development of alternative pest control agents. Compounds isolated from natural sources have emerged as preferred targets for the development of novel insecticidal agents because of their eco-friendliness, safety, and effectiveness. In this review, we primarily focus on the natural product (NPs) control of storage pests. The effective monomer components of NPs and their anti-insect mechanisms were discussed, and natural sources of inspiration and models for insect repellents are described. This review aimed to provide guidelines for the exploitation and utilization of green and efficient natural insecticides. 相似文献