9 kinds of lube oil viscosity index improvers were analysised comprehensively with the methods: samples 1~#～8~# were ethylene-propylene copolymers,their main sequential structures were EEE,PEP,EPE and PEE,their number average molecular weight were(52?000)～(120?000,) their polydispersities were 1.90～2.90,and their average polymerization degrees were also caculated;
Lube oil viscosity index improvers of unknown composition were analysised qualitatively with a spectroanalysis method,its main sequential structures and monomeric polymerization proportion were determined by()~1H-NMR,its molecular weight and distribution of molecular weight were given by GPC,and the polymerization degree was caculated by combination of()~1H-NMR/GPC.
The base oils of SAE 85W/90 vehicle gear oil and 220# industrial gear oil were obtained by blending Jingmen hydrogenated base stock HVI 500N and non-hydrogenated bright stock MVI 90BS in the right proportion, and adding pour point depressant and viscosity improvers viz.
The writers improvers the thermodynamics analysis methods of the injection steam boiler, which provides reference to analyze the energy consumption characteristics of the injection steam boiler thoroughly.
Within the temperature range of 600-800℃, the layer sructure changed, forming a new disordered structure, the coke precusor with disordered structure reached the greatest extent when improvers were used at this stage.
Reduction of Friction by Functionalised Viscosity Index Improvers
Dissipative particle dynamics (DPD), a new simulation technique that focuses on intermediate time and length scales, is evalu- ated for systems in which polymers are used as viscosity index improvers.
A high percentage of parents/guardians of non-improvers incorrectly believed that their child's condition had improved.
Compared to improvers, non-improvers ate fewer snacks (p = 0.01) and a greater percentage never consumed dried fruits (p >amp;lt; 0.01).
Fifty-one percent of the surveys were completed by parents/guardians of children classified as anemia improvers and 49% were completed by parents/guardians of children classified as anemia non-improvers.
The characteristics of Chinese domestic diesel fuels,their susceptibility to flow improvers,properties of doped fuels,and the proper use of the improvers were studied with emphasis on diesel fuels from Daqing crude oil.The results show that diesel fuels with pour point below -20℃ and -35℃ can be profitably produced from Daqing crude with the use of flow improvers.
The molecular structure of ethylene-vinyl acetate copolymers and their effects on the flowing property of diesel fuels from Daqing crude were studied in parallel with hydrocarbon group analysis and distillation test of the tested fuels. On the basis of the data obtained, a correlation between the copolymers and the fuels was found, and the conditions for production and proper use of one of these copolymer-type flow-improvers (T804) were recommended.