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31.
G.?Perretti E.?Finotti S.?Adamuccio R.?Della Sera L.?MontanariEmail author 《Journal of the American Oil Chemists' Society》2004,81(12):1119-1123
The aim of the present study was to highlight the main differences between seed oils produced from conventionally cultivated
crops and organically cultivated ones and processed using mild extraction procedures. The composition and the nutritional
and health aspects of both types of sunflower seed oils were compared and were analytically tested to determine the macroscopic
differences in proximate composition, the main differences in the minor components, the main quality parameters, the in vitro antioxidant activity, and the presence of trans-ethylene steroisomers in FA. No significant trends were found in the oil samples for TAG and FA composition, but remarkable
differences were found in the composition of minor components and in the main chemical and analytical quality properties.
The organically grown samples had a higher total antioxidant activity compared with the conventional samples. Trans FA were found only in the conventional oils. 相似文献
32.
介绍了锦化化工(集团)有限责任公司提高二次精制盐水质量的成功经验,讨论了过滤系统中碳素烧结管间距、一次盐水的质量及其游离氯含量、人为操作失误和助体给料量等五大因素对二次精制盐水质量的影响,并采取了相应的措施,如调整合适的碳素烧结管间距、改走砂滤器、更换过滤器碳素管等。介绍了二次精制盐水精制系统树脂塔精制盐水的操作要素,诸如控制盐水流量最高为68m3/h、温度在(60±5)℃、pH值在9左右,控制树脂塔的压差、树脂填充量、树脂性能、仪表阀的检查情况等,从而生产出高质量的二次精制盐水,保证了离子膜电解槽的平稳、高效运行。 相似文献
33.
Augusto Lanzón Tomás Albi Arturo Cert Jaime Gracián 《Journal of the American Oil Chemists' Society》1994,71(3):285-291
In numerous Spanish virgin olive oils, 6,10-dimethyl-1-undecene, various sesquiterpenes, the series ofn-alkanes from C14 to C35, n-8-heptadecene and squalene are the only less volatile components detected by gas chromatography
in the hydrocarbon fraction. In oils from olives of the Arbequine variety, a series ofn-9-alkenes has also been found. In refined oils, notable features are the absence of the most volatile compounds and the appearance
of other hydrocarbons produced during the refining process. Among these,n-alkanes, alkadienes (mainlyn-hexacosadiene), stigmasta-3,5-diene, isomerization products of squalene, isoprenoidal polyolefins coming from hydroxy derivatives
of squalene and steroidal hydrocarbons derived from 24-methylene cycloartanol were identified. Physical refining produces
larger amounts of degradation products and greater losses ofn-alkanes than chemical processing. Squalene is the major hydrocarbon component in all oils, both virgin and refined. The ranges
of concentration for the different hydrocarbons found in Spanish virgin olive oils are presented. 相似文献
34.
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36.
从精苯酸焦油废液中提取水泥减水剂的研究 总被引:1,自引:0,他引:1
研究了从精苯焦油废液中提取水泥减水剂的工艺过程.系统地分析了提取产品的各项物性指标.应用试验表明.对水泥的减水率达20%.同时水泥的抗折强度和抗压强度均有所提高.由此可以看出该提取物是一种优良的水泥减水剂. 相似文献
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38.
Bai-song Liu ) Guo-sen Zhu ) Huan-xi Li ) Ben-hai Li ) Yang cui ) Ai-min Cui ) ) School of Material Science Engineering Beihang University Beijing China ) Shougang Research Institute of Technology Beijing China ) Qian'an Iron Steel Company Qian'an China 《北京科技大学学报(英文版)》2010,17(1):22-27
The decarburization behaviors of ultra low carbon steel in a 210-t RH vacuum degasser were investigated under practical operating conditions.According to the apparent decarburization rate constant (KC) calculated by the carbon content in the samples taken from the hot melt in a ladle at an interval of 1-2 min,it is observed that the total decarburization reaction period in RH can be divided into the quick decarburization period and the stagnant decarburization period,which is quite different from the tradit... 相似文献
39.
A series of high nitrogen austenitic stainless steels were successfully developed with a pressurized electroslag remelting furnace. Nitride additives and deoxidizer were packed into the stainless steel pipes, and then the stainless steel pipes were welded on the surface of an electrode with low nitrogen content to prepare a compound electrode. Using Si3N4 as a nitrogen alloying source, the silicon contents in the ingots were prone to be out of the specification range, the electric current fluctuated greatly... 相似文献