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1.
崔敬佶  李中华 《润滑油》2006,21(1):9-13
随着工业和科技的发展,人类活动领域的扩大,对油品的使用要求更加苛刻,严寒、高温、超重负荷、高湿度和其他极端条件,都对油品提出了新的挑战,同时对环保和节能的要求也越来越严格。为适应这些更高的要求,近年来研制并逐步推出了三种更优异的合成基础油料:超高粘度指数的PAO,低蒸发性和低温粘度更小的PAO,以及新型Ⅴ类基础油烷基萘。其优异的特性使其在极端条件下提高油品的使用性能和减少设备磨损,更好地节能和环保,并延长设备使用寿命等方面,发挥了独特的作用。  相似文献   
2.
BF3作为α-烯烃齐聚反应催化剂,其含量控制对催化反应的调控与产品质量的把控至关重要。通过建立样品前处理方法、优化仪器测试条件与标准溶液配制方法,建立利用燃烧离子色谱测定BF3·醇催化的α-烯烃齐聚反应体系中F元素含量,进而计算出BF3含量的方法,并考察了方法的重复性和准确性。结果表明:利用该方法可测定BF3质量分数范围为2.68~53.50 g/kg的样品,前处理时适量的正丁醇和白油可有效稳定和稀释样品;测定稀释样品中F元素含量的标准曲线分为2段,线性范围分别为300~2000 mg/L和2000~3000 mg/L,线性相关系数R2分别为0.9992和0.9940;测定5次BF3质量分数结果相对标准偏差均小于5%,方法加标回收率在95.0%~105.0%之间,方法检出限取决于前处理时的取样量,当取样量为5 g时,检出限为1 mg/kg。  相似文献   
3.
This study analysed the enhanced biological phosphorus removal (EBPR) microbial community and metabolic performance of five full-scale EBPR systems by using fluorescence in situ hybridisation combined with off-line batch tests fed with acetate under anaerobic–aerobic conditions. The phosphorus accumulating organisms (PAOs) in all systems were stable and showed little variability between each plant, while glycogen accumulating organisms (GAOs) were present in two of the plants. The metabolic activity of each sludge showed the frequent involvement of the anaerobic tricarboxylic acid cycle (TCA) in PAO metabolism for the anaerobic generation of reducing equivalents, in addition to the more frequently reported glycolysis pathway. Metabolic variability in the use of the two pathways was also observed, between different systems and in the same system over time. The metabolic dynamics was linked to the availability of glycogen, where a higher utilisation of the glycolysis pathway was observed in the two systems employing side-stream hydrolysis, and the TCA cycle was more active in the A2O systems. Full-scale plants that showed higher glycolysis activity also exhibited superior P removal performance, suggesting that promotion of the glycolysis pathway over the TCA cycle could be beneficial towards the optimisation of EBPR systems.  相似文献   
4.
Oligomers of higher alphaolefins, mainly of 1-decene and 1-octene have important applications as synthetic lubricating oils or their components. The results of fractionation of polydecene, polyoctene, and polybutene oils in a wiped-film molecular evaporator, for the purpose of preparing narrow distillate cuts, are presented in the paper. Characteristics and properties of the fractions obtained are shown, and the possibilities for this distillation method in the fractionation of polyolefin oils discussed.  相似文献   
5.
废水生物除磷技术综述   总被引:4,自引:0,他引:4  
介绍和评述了生物除磷的两种机理,基于两种机理的除磷工艺,指出了它们的特点,探讨了今后除磷技术的发展方向.  相似文献   
6.
Compressors are used all over the world for various individual applications; the current application concerns their use in the ozone process of water treatment. Technical data on different mineral and synthetic lubricants are given. In particular, a new oil was chosen for investigation. Field testing was undertaken over more than 6000 h on two different locations. Used oil monitoring was conducted by sampling during the experiment; analyses of physical and chemical parameters were made and their kinetics are described. Wear, viscometrics and ozone process interaction are discussed in this study.  相似文献   
7.
This paper reviews the optimum synthetic and semi-synthetic lubricants for various types of compressors and gases being compressed. Several applications are given involving centrifugal, rotary, and reciprocating compressors. Gases include air, refrigerant, natural and other hydrocarbons, chemical processing and industrial. Included also are food grade air compressor applications. In addition, microlube systems for once-through cylinder lubrication of large reciprocating compressors designed to minimize gas contamination are also described.  相似文献   
8.
Hydrocarbon mixtures containing olefins were produced from waste polyethylene, and oils were synthesized from various fractions of these. Various properties of these products are presented including viscosity and pour point.  相似文献   
9.
The main aim of this research is to decrease the amount of AlCl3 content that is very corrosive and hazardous in the catalytic system, required for the α-olefin oligomerization without substantial change of final oil features. This was successfully achieved by supporting AlCl3 on different carriers. More precisely, a series of supported bimetallic catalysts was synthesized by immobilization of AlCl3 and TiCl4 onto Al2O3, SiO2, and mixed supports, that is, Al2O3/FeCl3 and SiO2/FeCl3. It was found that silica and alumina-based catalysts had higher catalytic activities compared to support free AlCl3; however, this enhancement for silica-based supports was more significant. According to gel permeation chromatography (GPC) results, the use of single supports, that is, Al2O3 and SiO2, increased oligomer's molecular weight, while the application of mixed supports resulted in the decrease of molecular weight of the oligomers. Viscosity characteristics of the synthesized oligomers have also been studied at two different temperatures of 40 and 100°C (KV40 and KV100). The viscosity index (VI) values, derived from KV40 and KV100, of the prepared oligomers were in the range of 126–145. The molecular weight and termination mechanisms of the oligomers were studied by 1H-NMR spectroscopy. The obtained results disclosed that the employed reaction conditions led to the production of oligomer chains with various structures including vinylidene (Vd), and di and three-substituted vinylene (2Vn, 3Vn) structures.  相似文献   
10.
聚α-烯烃合成油(Polymer Alpha olefins,简称PAO),是一类性能高的润滑剂与官能液,也是饱和烯烃的低聚物。其中,α-烯烃(主要为C_8~C_(12))的三、四聚体是合成润滑油基础油最主要的原料,且具有很高的粘度指数、低的倾点。主要选用1-癸烯为原料烯烃,通过加入多元醇配位体对三氯化铝进行改性,研究三氯化铝改性的催化剂对α-烯烃催化的齐聚反应的最佳工艺条件,计算齐聚产物的收率。  相似文献   
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