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用EVA复配物改善高含蜡原油低温流动性的研究 总被引:4,自引:0,他引:4
本文研究了采用化学处理剂改善南海高含蜡原油的低温流动性,结果表明,添加150ppm EVA复合化学处理剂,原油低温流动性得到明显改善,凝固点由32℃降至11.5℃,表观粘度降低86.9%,1;℃时屈服值降低98%。同时考察了添加温度,冷却速度以及化学处理剂的化学组成和结构对改善原油低温流动性的影响。根据南海高含蜡原油中蜡的组成和正构烷烃的碳数分布及其对不同结构的EVA的感受性,讨论了化学处理剂改善原油低温流动性的机理,指出,EVA中乙烯链长与原油中正构烷烃链长相近时才能形成共晶,起到改变原油中蜡的结晶形态的作用,达到降凝减粘效果。 相似文献
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Lynnette S. Walsh Hentges Donald C. Beitz Norman L. Jacobson A. Dare McGilliard Jeffrey J. Veenhuizen 《Lipids》1985,20(11):735-742
In a 2×2 factorial arrangement, miniature pigs were fed four diets containing vegetable protein/fat (soybean) and animal protein
(egg white)/fat (beef tallow) to demonstrate the effects of protein and fat source on total plasma cholesterol, lipoprotein
distribution, low density lipoprotein (LDL) composition, and plasma clearance of LDL-cholesterol and protein. Beef tallow
consumption resulted in greater plasma cholesterol concentration, decreased LDL-cholesterol concentration, and a lower LDL-cholesterol
to LDL-protein ratio than did consumption of soybean oil. High density lipoprotein (HDL)-cholesterol concentration was increased
by beef tallow consumption. Cholesterol percentage by weight in LDL was significantly greater in pigs consuming soybean oil
than those consuming beef tallow. Percentages by weight of protein, triglyceride and phospholipid in LDL were not significantly
different in any group. Dietary protein source had no significant effect on total plasma cholesterol concentration, lipoprotein
concentration or LDL composition. Egg white consumption decreased fractional catabolic rate and irreversible loss of LDL-cholesterol
and LDL-protein when compared with consumption of soy protein. Dietary fat source had no consistent effect on LDL clearance
from plasma. Dietary fat and protein seemed to influence lipoprotein metabolism by different mechanisms. Fat source altered
lipoprotein concentration and LDL composition, whereas protein source affected the removal rate of LDL from plasma.
Data taken from a dissertation submitted to Iowa State University by L. S. Walsh Hentges as partial fulfillment of the requirements
for the Ph.D. degree. A preliminary paper, was presented at the meeting of the American Oil Chemists' Society in Dallas, Texas,
May, 1984. 相似文献
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Howard Dare 《印刷技术》2006,(34)
现在,中国经济的高速增长使中国印刷业进入了一个快速发展的时代,同时其进出口市场也达到了一个新的制高点.现在,中国的制造和加工业已经越来越现代化,许多企业已采取与外国企业合资的方式进行生产经营,吸收先进技术和管理经验,使其质量水平得到大幅提升,而以此方式形成的低成本和高质量生产模式也帮助广大中国客户获得了市场的成功. 相似文献
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Olagunju Solomon O. Atayese Muftau O. Sakariyawo Olalekan S. Dare Enoch O. Nassir Adesola L. 《SILICON》2021,13(9):3059-3073
Silicon - Lodging resistance in upland rice requires adequate knowledge of the mechanical basis of culm morphological traits (CMTs) with potential for improved structural integrity under... 相似文献
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Dare K Akin-Ajani DO Odeku OA Itiola OA Odusote OM 《Drug development and industrial pharmacy》2006,32(3):357-365
A study has been made of the effects of pigeon pea starch obtained from the plant Cajanus cajan (L) Millisp. (family Fabaceae) and plantain starch obtained from the unripe fruit of Musa paradisiaca L. (family Musaceae) on the compressional, mechanical, and disintegration properties of paracetamol tablets in comparison with official corn starch BP. Analysis of compressional properties was done by using density measurements, and the Heckel and Kawakita equations, whereas the mechanical properties of the tablets were evaluated by using tensile strength (T--a measure of bond strength) and brittle fracture index (BFI--a measure of lamination tendency). The ranking for the mean yield pressure, P(y), for the formulations containing the different starches was generally corn < pigeon pea < plantain starch while the ranking for P(k), an inverse measure of the amount of plasticity, was pigeon pea < plantain < corn starch, which indicated that formulations containing corn starch generally exhibited the fastest onset of plastic deformation, whereas those formulations containing pigeon pea starch exhibited the highest amount of plastic deformation during tableting. The tensile strength of the tablets increased with increase in concentration of the starches while the Brittle Fracture Index decreased. The ranking for T was pigeon pea > plantain > corn starch while the ranking for BFI was corn > plantain > pigeon pea starch. The bonding capacity of the formulations was in general agreement with the tensile strength results. The disintegration time (DT) of the formulation increased with concentration of plantain and corn starches but decreased with concentration of pigeon pea starch. The general ranking of DT values was plantain < pigeon pea < corn starch. Notably, formulations containing pigeon pea starch exhibited the highest bond strength and lowest brittleness, suggesting the usefulness of pigeon pea starch in producing strong tablets with minimal lamination tendency. Plantain starch, on the other hand, would be more useful where faster disintegration of tablet is desired. The results show that the starches could be useful in various formulations depending on the intended use of the tablets with the implication that the experimental starches can be developed for commercial purposes. 相似文献
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Deterministic table 0L array systems with control are considered for the generation of infinite arrays. Rewriting of a rectangular array is done in parallel by a table of rules, the rightmost edge horizontally or the lowermost edge vertically downwards. The application of the tables is controlled by a control set. Cube-free and square-free infinite arrays are obtained as an application of this model. The adherence of the array language of a controlled deterministic table 0L array system is related to the adherence of its control set. The limit language equivalence problem and the adherence equivalence problem are shown to be undecidable for this system. 相似文献
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I Eisler C Dare GF Russell G Szmukler D le Grange E Dodge 《Canadian Metallurgical Quarterly》1997,54(11):1025-1030
The high prevalence of premature attrition from psychotherapy is a phenomenon which has been well recognized in the psychological literature. The pressing concern that a number of clients may not be benefiting from treatment because they are dropping out has led to a plethora of research in the area of individual psychotherapy. No studies, however, have attempted to investigate the characteristics of dropout in group cognitive behaviour therapy for depression. To address this gap in research, the present study examined the factors associated with dropout in a group cognitive behaviour therapy for depression, using 131 Ss who went through the group therapy for 12 weeks. The results showed that sociodemographic measures (e.g. age) and measures of depressive symptoms (e.g. depression scores) did not discriminate dropouts from completers. An investigation of patterns of mood changes in the course of the therapy also failed to find significant differences between the dropouts and completers. However, weekly therapist rating of client participation revealed that dropouts participated significantly less than completers during the therapy sessions. The results are discussed in light of the findings of current literature and future research in premature attrition. 相似文献