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101.
实验考察了8种市售水溶性破乳荆对长庆油田陕北区有代表性的宝塔区、安塞和子长原油(均为低硫中间基-石蜡基原油)的脱水效果(加量100mg/L,脱水温度55℃,时间3h)。目前长庆采油一厂使用的YT-100和延炼集团使用的GT-940对这3种原油的脱水效果均较好,但对子长原油的脱水率不高,分别为69.7%和58.9%。在由所选性能较好的破乳刺组成的4种二元复配物中,GT-940 HQ96-1对3种原油的脱水效果均高于单剂,最佳配比分别为4:1,4:1,3:2;其余3种复配物则对原油有选择性,其中GT-940 YT-100相近(97.5%);YT-100 HQ96-1仅能改善子长原油的脱水效果,配比为4:1时脱水率最高(76.4%);SP-169 HQ96-1仅能改善宝塔区原油的脱水效果.配比3:2和2:3时脱水率最高(92.9%)。表5参6。 相似文献
102.
M J Gatti M E Fraga C Magnoli A M Dalcero C A da Rocha Rosa 《Food Additives & Contaminants》2003,20(12):1120-1126
A mycological survey was carried out on 115 samples of whole dried black pepper seeds, from two main production regions of Brazil (Pará and Espírito Santo). A high incidence of contamination was verified in both regions when 99.1% of the samples showed filamentous fungi contamination. A total of 497 species of nine different genera were isolated (Aspergillus, Eurotium, Rhizopus, Penicillium, Curvularia, Cladosporium, Absidia, Emericella and Paecilomyces). The genus Aspergillus was the predominant (53.5%) followed by species from the Eurotium genus (24.5%). Eurotium chevalieri (16.4%) was the most predominant species followed by A. flavus (14.6%) present on 55 samples of black pepper (47.8%) analysed. Twenty-five samples (21.7%) were contaminated with aflatoxigenic strains of A. flavus and A. parasiticus. In relation to the types of aflatoxins produced by mycotoxigenic strains, it was observed that 25 strains (44.6%) of 56 isolated of A. flavus produced aflatoxins. From 12 samples, A. ochraceus species were isolated in low frequency (3.5%). Two strains of A. ochraceus from 16 isolated were producers of ochratoxin A. With respect to the aflatoxins and ochratoxin A natural contamination, none of the samples presented detectable levels of these mycotoxins using thin-layer chromatographic analysis. 相似文献
103.
104.
用分光光度计测定了12例兔角膜和1例人角膜的吸收光谱,结果表明波长小于300nm的准分子激光和波长在1.88μm~2.64μm,2.36μm~40μm的激光,均可对角膜进行切割并可望用于激光角膜矫正术。 相似文献
105.
106.
郭瑞璜 《消防技术与产品信息》2002,(3):60-64
关东大地震火灾 ,可谓 2 0世纪世界上最大的地震火灾 ,造成的人员伤亡和财产损失确实称得上前所未有。最近 ,有关方面正在吸取阪神大地震的教训 ,实施各种防灾对策。笔者以为 ,只有把确实存在着严重程度远远超过阪神大地震的灾害这件事 ,牢牢铭刻在头脑中 ,理顺对付罕见的大灾害的基本思路 ,才能从总体上全面地研究灾害对策。而且 ,关东大地震火灾的有些问题至今尚未研究清楚 ,笔者切望彻底搞清这些问题 ,以促进火灾工程学的发展。有鉴于此 ,有必要对关东大地震火灾这一历史性大灾害作一番回顾。1.关东大地震的调查情况关东大地震发生在 192… 相似文献
107.
Microwave irradiation processing (MIP) was considered as a potential method to synthesize perovskite-type oxides rapidly, cleanly and energy-efficiently. In this paper, La0.7Sr0.3MnO3+λ, a kind of promising catalyst for automobile exhaust purification, was successfully prepared by MIP in not more than 5 min. The sol–gel method was also used for comparison. All the samples were evaluated by catalytic activity tests in the simulated exhaust and characterized by XRD, BET, TEM and XRF analyses. The results showed that the integrated perovskite-type phase and uniform particle size were obtained in the microwave-treated samples. And those ones exhibited a better oxidation activity under slightly oxygen-rich condition than that by sol–gel method, which may be related to more A-site cation vacancies and larger bulk oxygen content generated in MIP. Possible formation mechanism of perovskites in MIP was also discussed. 相似文献
108.
李睿 《数字社区&智能家居》2007,(11):608-610
在ERP及其他数据库开发项目中.方便而操作风格一致的录入界面是被用户所广泛要求的。笔者在工程项目中总结了部分用户需要的功能.并在PowerBuilder中以基类的形式实现.在加快工程进度和方便用户方面取得了不错的效果。 相似文献
109.
V Schirrmacher U Beutner M Bucur V Umansky M Rocha P von Hoegen 《Canadian Metallurgical Quarterly》1998,161(2):563-570
From a cross between a tumor-susceptible mouse strain (DBA/2; D) and a tumor-resistant MHC-identical strain (B10.D2; D2) new recombinant inbred mouse strains were established over many generations of inbreeding and tumor resistance selection. Since resistance to the highly metastatic DBA/2 lymphoma variant ESb had an immunologic basis, and the two parental strains differed in endogenous viral superantigens (vSAGs), DNA of three D2 x D recombinant inbred mouse lines was typed for endogenous mouse mammary tumor viruses using mouse mammary tumor virus long terminal repeat- and env gene-specific probes. The resistant D2 x D mice were very similar to the susceptible parental strain D in their Mtv Southern blots, except for the lack of a single band corresponding to Mtv-7, the provirus coding for the strong DBA/2 superantigen Mls-1a. A backcross analysis revealed that Mtv-7-negative F2 mice were significantly more resistant than Mtv-7-positive F2 mice. When Mtv-7 was reintroduced into the resistant lines by crossing them with either CBA/J or BALB/D2.Mls-1a, the mice became again more tumor susceptible. Finally, we demonstrate the ability to transfer immunoresistance and graft-vs-leukemia reactivity from tumor-resistant to tumor-susceptible mice. 相似文献
110.