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1.
C. N. Haas B. F. Severin D. Roy R. S. Engelbrecht A. Lalchandani S. Farooq 《Water research》1985,19(3):323-329
This paper summarizes studies on the presence of acid-fast and yeast organisms in wastewater and water treatment plants and in surface water. These organisms were found to satisfy three of Bonde's criteria for indicator organisms: presence whenever pathogens are likely to be present; resistance at least equal to that of pathogens; and lack of regrowth in the post-treatment environment. This, plus prior data, indicates that these organisms are at least as acceptable as indicators of disinfection efficiency than the coliform group. 相似文献
2.
仲胺衍生物柴油流动改进剂 总被引:2,自引:0,他引:2
考察了十八种胺衍生物改善高含蜡柴油低温流动性的作用规律。结果表明,仲胺衍生物主要是通过增溶柴油中的长链正构烷烃,使浊点、冷滤点降低,从而改善柴油低温性能。仲胺衍生物与T1804流动改进剂(乙烯-醋酸乙烯酯聚合物)复合可以改善蜡晶的分散性能,对降低柴油冷滤点有增效作用。 相似文献
3.
4.
The extraction of nitrogenous material from Brewers' spent grain (BSG) by solvents (water, sodium chloride solution, aqueous alcohol, acidic and alkaline solutions) commonly used to extract cereal proteins, resulted in the relatively low (0·2 to 8·5%) recovery of the total nitrogen. The recovery of nitrogenous material by the use of aqueous alkaline solutions was increased from 3–4% to 41% when the BSG was subjected to cellulase incubation prior to extraction. Approximately 75% of the nitrogen was solubilized with trifluoracetic acid. Detergent solutions (acid, neutral) solubilized more than 80% of the total nitrogen of the BSG. The low solubility of the nitrogenous constituents by conventional protein solvents could be the result of association between cellulosic material and protein. 相似文献
5.
A study was undertaken to examine the sensitivity of a wastewater population of coliphage, total coliforms and total flora present in raw sewage and secondary effluent after irradiating with similar doses delivered by a high-energy electron beam and y -radiation. The electron beam study was conducted on a large scale at the Virginia Key Wastewater Treatment Plant, Miami, Fla. The facility is equipped with a 1.5 MeV, 50 mA electron accelerator, with a wastewater flow rate of 8 ls−1. Concurrent y-radiation studies were conducted at laboratory scale using a 5000 Ci, 60Co y -source. Three logs reduction of all three test organisms were observed at an electron beam dose of 500 krads, while at least four logs reduction were observed at the same dose utilizing the y-source. 相似文献
6.
稳定态二氧化氯杀菌剂的制备及应用 总被引:3,自引:0,他引:3
稳定态二氧化氯(C1O2)是一新型杀菌消毒剂,具有高效、广谱、安全的特性,适用范围广,不产生对人体有害物质。介绍了稳定态ClO2的性质、检测、制备条件及其在有关领域的应用。 相似文献
7.
新型组合工艺对微污染原水中有机污染物和消毒副产物前体物的去除 总被引:1,自引:1,他引:1
本采用中试试验装置研究了生物陶粒过滤一微絮凝砂滤一活性炭吸附组合工艺,对微污染原水中有机污染物和消毒副产物前体物的去除效果。在原水UV254为0.047~0.065cm^-1,DOC为2.70~4.10mg/L,TOC为3.50~5.00mg/L的条件下,组合工艺对UV254,DOC、TOC平均去除率分别为98.4%、74.1%、69.2%。色-质联机分析结果表明,经组合工艺处理水中有机物由54种降至25种。组合工艺出水中三卤甲烷总含量不及常规工艺出水中该物质含量的五分之一。组合工艺能有效控制和消除水中有机物的污染,提供安全的优质饮用水。 相似文献
8.
D. Wiesenborn Z. Zbikowski H. Nguyen 《Journal of the American Oil Chemists' Society》1995,72(2):183-188
Extract of purple sunflower hulls is a potential red food colorant; however, suitable process conditions must still be identified.
Selected process variables were studied using bench-scale units to prepare, clarify, concentrate and spray dry extracts. Concentration
by evaporation at 32°C and addition of maltodextrin to 15% (wt/dry wt) prior to drying largely eliminated pigment degradation
during those steps. Relative to water extracts, extracts prepared with 5 to 15% ethanol in water generally yielded more pigment
with similar levels of degradation and loss during subsequent processing. Use of 5% ethanol/2% citric acid reduced yield by
about half relative to water, but gave a powder with a lower degradation index and wetting time. Percentage recovery of pigment
during concentration and drying was not greatly affected by solvent type or extraction temperature. 相似文献
9.
油田废水电解杀菌研究 总被引:1,自引:0,他引:1
采用电解杀菌技术处理油田废水,研究了电解时间、电流强度、极板间距以及电极联结方式等因素对废水中硫酸盐还原菌杀灭效果的影响。结果表明,油田废水经3min电解杀菌,硫酸盐还原菌杀灭率高达99.90%。随着电解时间的增加,硫酸盐还原菌的杀菌率进一步提高;电流强度增加,硫酸盐还原菌的杀灭率升高。在电流强度保持不变的情况下,随着极板间距增加,极板之间电压升高,更有利于杀灭硫酸盐还原菌。在极板间电流强度相同的条件下,两种电极联结方式的杀菌率差别不大,杀菌率均在99.9%以上。 相似文献
10.