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971.
丁亚军 《自动化技术与应用》2012,31(8):91-93
一种用于油井井口的中频电磁加热器。外表面缠绕电磁感应线圈的导磁钢管做为换热器的主要部件。在导磁钢管靠近出油口设置有管壁温度检测传感器和油温检测传感器,检测到的温度信号经过检测电路处理后,送给控制器,实现控制与保护。该中频电磁加热器加热速度快,热效率高,调温、控温容易。 相似文献
972.
973.
974.
艾叶精油化学成分研究 总被引:7,自引:1,他引:7
本文用水蒸气蒸馏法提取了不同产地艾叶精油,采用GC-MS技术分析了艾叶精油的化学成分。结果不同产地艾叶精油的质量收率为0.29%~0.56%,都含有特征成分:α-蒎烯、β-蒎烯、α-松油烯、γ-松油烯、桉叶素、蒿酮、蒿醇、2-环己烯-1-醇、樟脑、龙脑、4-松油醇、反式-石竹烯、丁子香酚。其中具有药效作用的成分有桉叶素(14.32%~26.12%,质量百分数,下同),樟脑(3.66%~14.97%)、龙脑(0.51%~10.53%)、甘菊环(0.00%~23.95%)等,有毒成分侧柏酮含量为0.32%~3.62%。 相似文献
975.
Charles A. Pittinger Jere S. Sellers Daniel C. Janzen Dianne G. Koch T. Michael Rothgeb Michael L. Hunnicutt 《Journal of the American Oil Chemists' Society》1993,70(1):1-15
Life-cycle inventories were compiled to characterize natural resource requirements and environmental emissions associated
with the sourcing and production of selected, detergent-grade surfactants and surfactant feedstocks. Petrochemical surfactant
types examined were linear alkylbenzene sulfonate, alcohol sulfate (AS), alcohol ethoxylate (AE) and alcohol ethoxylate sulfate
(AES). Oleochemical surfactants derived from palm oil, palm kernel oil and inedible tallow were AS, AE, AES and (for palm
oil and tallow) methyl ester sulfonate. It was determined that natural resource requirements were primarily related to the
source of feedstock and secondarily to surfactant type. Likewise, the composition and mass of atmospheric, aqueous and solid
emissions were principally determined by feedstock source. Energy requirements varied as a function of both feedstock and
surfactant type. The inventories do not support fundamental shifts in surfactant usage or feedstock sourcing on the basis
of environmental concerns, as no single surfactant or feedstock was identified as superior across all resource and emissions
criteria examined. The data provide baselines for evaluating opportunities for resource optimization, pollution prevention
and waste minimization within each production technology surveyed. 相似文献
976.
分析延迟焦化装置干气脱硫系统净化干气中烯烃、硫含量达不到设计值的原因,通过调整柴油吸收及换热系统工艺流程、改造脱硫塔内件、溶剂再生塔和换用新型溶剂,使净化干气的各项指标达到制氢原料的要求,取得好的经济效益。 相似文献
977.
超临界CO_2萃取芹菜籽油研究 总被引:14,自引:2,他引:14
用超临界CO2萃取技术对广东白芹菜籽进行了萃取研究。结果表明,萃取压力低于15MPa时,较重的油树脂等成分难以被萃取出来;萃取温度为308K时对萃取最有利;解析温度对萃取效率影响较小;CO2流量对萃取效率的影响比床层高度引起的扩散阻力的影响大得多。超临界CO2萃取所得芹菜籽油品质优越,且其中的药用有效成分(3-正丁基-4,5-二氢苯并呋喃酮)含量比水汽法所得芹菜籽油的高五倍多。 相似文献
978.
综述了近年来国内一些大专院校利用超声的破乳作用进行乳化原油声.化学法脱水研究的进展情况。尽管文中涉及到的是油田原油脱水,但与炼油厂原油的预处理脱水有共同之处。作为借鉴,乳化原油声-化学法脱水研究可为炼油厂原油的预处理提供一条新途径。 相似文献
979.
980.
R. F. Wilson W. P. Novitzky G. P. Fenner 《Journal of the American Oil Chemists' Society》1995,72(12):1425-1429
Fungal damage caused by pathogens such asFusarium, Cercospora, andPhomopsis can have a devastating impact on physical quality and farm price of soybeans. In some price-discount schedules, soybeans
may be rejected with as low as 5% fungal damage. Although the severity of this problem varies throughout the United States,
millions of bushels of fungus-damaged soybeans may be destroyed annually due to a lack of markets. The effect of fungal damage
on seed composition was evaluated to assess potential utility of highly damaged soybeans. Graded samples of the cv. Centennial
soybean were dried to 10% moisture and blended on a proportional weight basis to derive a series of treatments from 0 to 80%
fungal damage. A positive correlation was found between fungal damage and both protein and oil concentrations. This condition
was attributed to loss of residual seed mass. As a result, the protein concentration of defatted meal increased from ca. 54
to 66% over the range of 0 to 80% fungal damage. Mycotoxin contamination appeared to be insignificant in these high-protein
meals. Fixed colors in bleached, alkali refined oils were intensified by heat treatment prior to extraction. No significant
differences, however, were noted in total polar lipid content, phospholipid, or tocopherol composition among treatments of
up to 20% fungal damage. Oils from treatments of more than 40% fungal damage were more severely oxidized and could not be
degummed effectively. These data suggest that fungus-damaged soybeans may be blended with high-quality soybeans to alleviate
the chemical symptoms associated with unacceptable product quality. Thus, through various blend ratios, processors may consider
using fungus-damaged soybeans to gain economic advantage, especially when high-quality soybeans have lower protein concentration. 相似文献