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辽河油田石化总厂为提高从辽河原油生产重交通道路沥青的质量,对所用的辽河原油中的低凝点环烷基原油经过分储、分输、分炼,对减压蒸馏塔进行改造,控制减压拔出率,对直馏沥青进行轻度氧化,使90号重交通道路沥青中沥青质的含量大于10%,蜡含量小于2%,质量达到了国际先进水平。 相似文献
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我国金矿床氧化带的地质地球化学特征 总被引:1,自引:0,他引:1
根据氧化矿石的主要化学成分,应用FAS图解进行氧化矿石的化学成分分类;通过对氧化带分带及发育型式的研究,建立了我国金矿氧化带形成的地质地球化学模式;对影响氧化带发育的因素进行了初步探讨。 相似文献
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Cholesterol oxidation in lard containing two levels of added cholesterol was monitored using capillary gaschromatography.
Loss of cholesterol and formation of cholesterol oxidation products (COPs) were measured. Lard samples with 10 times (Test
I) and 2 times (Test II) the amount of cholesterol originally found in each batch of lard were heated at 180°C for 10 hr a
day for 240 and 160 hr, respectively. Cholesterol steadily decreased throughout the heating period in both tests. Cholesterol
loss followed a first-order reaction rate, with a rate constant (k) of −1.18×10−3 h−1 for Test I and −9.45×10−3 h−1 for Test II. The COPs accumulated during both heating tests. But the amount of COPs formed did not total the amount of cholesterol
lost. During heating, thermal degradation of cholesterol likely occurred, and those products were not detected. During cooling,
hydroperoxides formed, which further oxidized into the COPs that were detected. The 7-ketocholesterol and 5α,6α-epoxycholesterol
were the predominant COPs formed. The isomeric 7α-and 7β-hydroxycholesterols also accumulated in the heating tests. The 3β,5α,6β-cholestantriol
was found in very small amounts and the 25-hydroxycholesterol was not detected.
Presented in part at the 80th AOCS Annual Meeting, Cincinnati, OH, in May, 1989. 相似文献
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快干型芭蕉芋淀粉粘合剂的制备 总被引:2,自引:0,他引:2
介绍一种快干型芭蕉芋淀粉粘合剂,它特别适合于粘结瓦楞纸板,其制法是芭蕉芋等直链淀粉含量较代低的天然植物淀粉为原料,经氧化、糊化、交联等步骤而制得;产品结力强,产品性能稳定,贮存期长。 相似文献
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Copolythiophenes (Co‐PTs), poly(3‐hexylthiophene‐co‐3‐thiophene carboxylic acid) (P3HT‐TCa), poly(3‐hexyloxylthiophene‐co‐3‐thiophene carboxylic acid) (P3HOT‐TCa), and poly(3‐phenylthiophene‐co‐3‐thiophene carboxylic acid) (P3PhT‐TCa), were synthesized by chemical oxidized polymerization to investigate the effect of copolymerization on the properties of polythiophenes (PTs). Gel permeation chromatography showed that the molecular weight (MW) of Co‐PT was lower than that of homopolythiophene. Fourier transform infrared (FTIR) spectra indicated that the copolymerization was successful between the monomers. The λmax of Co‐PTs gave a “blue shift” in ultraviolet‐visible (UV‐VIS) spectra. Photoluminescence (PL) spectra showed that the PL intensity of Co‐PT became weaker than that of homopolythiophene and the disappearance of PL had been observed in P3HOT‐TCa. The thermal stability of Co‐PT was influenced by the carboxyl for its low decomposition temperature. Furthermore, the copolymerization between multi‐wall carbon nanotube containing thiophene ring (MWNT‐Th) and 3‐hexyloxylthiphene could also take place successfully. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
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