Papers by Author: Xiao Long Lu

Abstract: In this study, PVDF membranes were prepared by solution-cast method. The effects of evaporation temperature on the morphology, polymorph and mechanical properties of such prepared membranes were studied. It was found that perfect spherulites were observed in the solution-cast membranes. FESEM photomicrographs of the membranes showed dense structure. PVDF mainly crystallized into α phase. In the solution-cast process, the spherulite size increased as evaporation temperature was increased from 120 °C to 150 °C, when the evaporation temperature was 165 °C, spherulite size decreased. And the tensile strength increased with the decrease in spherulite size.

Abstract: Based on studying of ore property and tests, the suitable mineral processing flowsheet for the tin—iron ore had been determined. Better technical and economic indexes had been achieved: the iron concentrate grade reached 64.45%, and the tin concentrate grade reached 13.06%. It gave a technical reference to rational development and utilization of such kind of tin-iron ore resource.

Abstract: Emulsified oil is one of the main pollutants in condensed water. At present, the difficulties in demulsification of emulsified oil and dephenolization of petroleum ether are the main challenges in quantitative determination of emulsified oil in water by UV spectrophotometry. In this paper, second derivative ultraviolet spectrophotometry and demulsification with NaCl and ultrasonic were adopted to eliminate the disturbance of petroleum ether and avoid dephenolization process. Results show that the linear range of the standard oil is from 0 to 30mg/L, the recovery lies between 90.4%-101.6%, the relative errors are no more than 3%, the coefficient of variation are no more than 1.4%, and the repeatability standard deviation is only 0.1366. These results indicate that the emulsified oil detection method established has such advantages as high sensitivity, little interference, simple determination procedure, and accurate and reliable measuring result.

Abstract: Based on the dispersion characters of organic modified attapulgite (OAT) short fibers in nature rubber (NR) matrix, this paper analyzed the effects, in terms of addition amount of OAT, processing technology of rubber compound and heat treatment, on mechanical properties and anisotropy of OAT/NR composites. Results indicated that mechanical properties were better when the OAT content is 50 phr and thin-passing is 20 times, meanwhile, the longitudinal and transversal tensile strength of OAT/NR composites were 17.01 0.5 Mpa and 14.18 0.5 Mpa respectively. The anisotropy is obvious. Also the tensile and tear broken section were studied by the scanning electron microscope (SEM) and the forming mechanism of OAT/NR anisotropy composites was discussed.