Advanced Materials Research Vols. 1049-1050

Abstract: Well-defined triblock terpolymer polystyrene-block-poly (N,N-Dimethylaminoethyl methacrylate)-block-poly (methyl methacrylate) (PS-PDMAEMA-PMMA) is synthesized via sequential Atom transfer radical polymerization (ATRP) with designed molecular weights characterized by HNMR and GPC. Annealing in Chloroform which is a selective solvent for PS and PMMA induces the formation of micelles with patchy coronas, and subsequent dialysis against cyclohexane which is selective only for PS enables the stacking of the precursor micelles into core-compartmentalized self-assemblies. The micellizatinon and self-assembly behaviors are investigated via DLS and TEM.

Abstract: In order to obtain an ideal sample inlet membrane for ion mobility spectrometers (IMS), fumed silica was modified using hexamethyldisilazane and was incorporated into the matrix of polydimethylsiloxane (PDMS) silicone rubber to fabricate PDMS/silica mixed matrix membranes with different thickness. Dimethyl methylphosphonate (DMMP) permeability of thin silicone rubber membranes (SRM) with the least thickness of approximate 5μm was studied. DMMP concentration interior to the SRM showed the linear correlation to that external to the SRM. Thickness and temperature of SRM were two important factors influencing the permeation proportion of DMMP. Most water vapor was prevented to transfer through the SRM. In addition, the SRM had a good selectivity of DMMP/water vapor and the maximum separation factor was 4.82 when the temperature of membranes reached 80 °C.

Abstract: A numerical simulation method is hereby adopted in this paper to calculate and analyze the thermal dispersion influence factors of three particle-shaped porous mediums of two-dimensional porous medium with different skeleton structures. Result shows that the thermal dispersion influence factors include fluid thermal properties, Darcy velocity, porosity and skeleton structure, etc. Under the same condition, the thermal dispersion coefficient of a circular particle model is maximum, and it increases with the rise of Pe_d number; with the increase of the porosity or the reduction of Darcy velocity, the thermal dispersion coefficient reduces increasingly. When considering the thermal dispersion effect, the axial temperature variation of fluid is more applicable for numerical simulation, which proves that it shall consider the thermal dispersion during researches on porous medium models.

Abstract: The effectiveness of combined coagulation and Fenton oxidation to pharmaceutical plant wastewater was investigated under different operational conditions such as pH, dosage, coagulants and ratio of Fe²⁺ to H₂O₂. Among the nonionic polyacrylamide, cationic polyacrylamide, anionic polyacrylamide, polyaluminum chloride and polymeric ferric sulfate, anionic polyacrylamide showed the best efficiency of coagulation for the pharmaceutical plant wastewater. The results also showed that after the combined coagulation and Fenton oxidation treatment, the COD and color were reduced by 69.9% and 78.9%, respectively. The BOD₅/ COD ratio increased from 0.09 in initial to 0.22 after treatment. The wastewater of outlet was easier for the sequent biological process.

Abstract: . New developments in green catalytic oxidations of alcohols with H₂O₂ as oxidant in last decade are reviewed. Emphasis is placed on introducing the heterogeneous catalysts supported on different material in various of reactions, mechanism features are discussed as well.

Abstract: The solid particle erosion behaviors of TC4 Alloy were studied at different erosion angles. The results show that the erosion rate of TC4 alloy at impact angle 30^o was higher than those at the impact angles of both 60^o and 90^o. At low impact angle, the erosion mechanism could be concluded as grinding erosion and furrow erosion. However, the erosion mechanism could be fatigue erosion at large impact angle.

Abstract: A study of rare earth effects on inclusion modality of 8Cr4MoV cold work roll steels was carried out in the laboratory, the steels smelting by a 50kg vacuum induction furnace, atmospheric casting, processing sample after annealing, then inspecting the steels’microstructure, inclusion modality and composition; The results showed that the steels’ microstructure fine, micro-hardness increased with increasing rare earth content, while the average size of inclusions decreased significantly, also the morphology and composition of inclusions significantly changed from the angular black manganese sulfide to the ball white sulfur oxides of rare earth, and thus played roles of deoxidation, desulfurization, purification and deterioration of liquid steel , it will help improving the fatigue performance of the work roll.

Abstract: Geopolymeric material (geopolymer) was synthesized by casting and curing method using Bayer process red mud and metakaolin as starting materials. The fixation ability of the geopolymer for Pb²⁺ was studied by leaching method. The results shown that metakaolin played the role of aluminum and silicon donor during the initial strong alkaline aqueous phase. Red mud had principally the role of filler, increasing in this way the final compressive strength of the geopolymer. The compress strength of geopolymer curing 3 days from metakaolin and red mud mixture is 66MPa. The leaching concentration of Pb²⁺ from 50% red mud geopolymer is 0.891mg/L as the Pb²⁺ content in geopolymer is 2.5%; the metakaolin-red mud geopolymer has better Pb²⁺ fixation ability than metakaolin geopolymer.

Abstract: Through analyzing the operational performance of typical cyclones, including pressure drop and flow ratio, few operation features of the cyclones with different design has been deduced. The relationship between design and the operational features has also been analyzed. This paper mostly introduced the variety between the pressure drop and flux and the outlet size impacting on the flow ratio.

Abstract: Safe city system due to the particularity of data types, with the increase of access points, how to efficient organize and store the large multiple types of large-scale data is the hotspot and difficulty in research in recent years. Safe City system based on massive amount of data, a wide variety of features, designed to use distributed storage solution. On the basis of the Hadoop HBase distributed computing architecture, using the Blur services, design and implement safe city system based on Hadoop . Experiments show that the system has good expansibility, storage and query efficiency, can effectively solve the concurrent access to huge amounts of data.