Advanced Materials Research Vols. 864-867

Abstract: The influence of the degree of crystallinity of polymers on their elasticity modulus has been analyzed. Consideration was made of the situation when the amorphous parts of the polymers were in the rubbery state. A semi-crystalline polymer was considered in the form of a polymeric network in which the crystallites played the role of physical cross-links. Generalized equation of the rubber elasticity was applied to the analysis; this equation contained the Van-der-Waals volume of the cross-links and also the volume of a repeat unit of linear fragments. It was found that reduction of the crystallites size down to nanosize essentially increased the elasticity modulus at their fixed concentration.

Abstract: We have mental heat treatment for 22MnB5 steel with seven different experimental schemes and have mechanical property test on the seven steels. Then the microstructure and mechanical property of treated steels are studied, and the results show that 300°C is the optimum preservation temperature, at which we can get the optimum specific elongation of 22MnB5 steel. The tensile strength of steel thermal insulated at 300°C for 3 minutes is better than that of steel tempered at 300°C for 3 minutes, while as for specific elongation , the latter one is better. And we can also get homogeneous lath martensite after die quenching. The experiment lays foundations of the actual production process of hot forming.

Abstract: The calcium peroxide microparticles were synthesized and evaluated as an innovative oxidant to remove Fe (III) and Cr (III) from waste liquid of COD determining samples. The CaO₂ microparticles were 0.1-0.3 μm in diameter and the average CaO₂ content was 80%. Experiments were performed to investigate the influence of contact time, pH of solution and CaO₂ microparticles dosage on the efficiency of Fe (III) and Cr (III) removal. Up to 100.0% and 99.8% removal efficiency for Fe (III) and Cr (III) respectively was obtained by microparticles dosage of 10000 mg/L at 30 min and pH 7.46. It could be concluded that the removal efficiency was enhanced by increasing CaO₂ microparticles dosage and reaction time, but decreased by increasing pH. These results suggest that CaO₂ microparticles may be used to develop a simple and efficient removal method for waste liquid of COD determining samples.

Abstract: The NaA zeolite membranes with high permeance were synthesized by seeding and secondary growth both using vapor phase transformation method (VPT). The SEM image of seed layer on substrate indicated that the size of seeds was about 60nm. The XRD patterns showed that the formation of NaA zeolite membrane was after vapor phase transformation of 12h, and the pure NaA zeolite crystals formed on substrate. The SEM images showed that the NaA zeolite membrane consisted of compact polycrystalline crystals with an average size of ca. 2µm. The permeation results showed that the H2 permeance s of NaA membranes attained at the level of 10-6 mol/Pa·m2·s, and the maximum permselectivities of the H2/N2, H2/CO and H2/C3H8 were 4.15,4.78 and 10.1, respectively, which were higher than those of the corresponding Knudsen diffusion selectivities. However, the permeation of C3H8 suggested that there existed unwanted intercrystalline pores or defects in the membranes.

Abstract: Ethylenediamine-modified magnetic chitosan microspheres (EMCS) were prepared and used for the adsorption of Reactive Brilliant Red X-3B (RBR), Reactive Light Yellow K-6G (RLY) and Reactive Brilliant Blue X-BR (RBB). The EMCS has good adsorption performance for RBR and RLY. When the pH was 5.3 and 5.8 at 298K, initial concentration was 200mg/L, the adsorption capacity for RBR and RLY reached 98% and the maximum adsorption quantity achieve 198.99 and 122.2mg/g respective. The adsorption capacity of RBB on EMCS was unideal (<10%). The adsorption isotherm of RBR was fitted by both Langmuir and Freundlich equation, and the adsorption isotherm of RLY turned out to be more agree with Langmuir equation. The adsorption process follows a pseudo-second-order kinetic model for both RBR and RLY.

Abstract: Diatomite plays a very important role in sewage adsorption and especially has vast prospect in adsorbing heavy metal ions. The paper, on the basis of domestic and overseas literatures concerning diatomite, summarizes the modification methods of diatomite and adsorption research of heavy metal ions. Besides, it also forecasts the prospect of using diatomite to specifically adsorb heavy metal ion.

Abstract: Hollow glass microspheres loaded with ZnO nanoparticles were fabricated from amber colored glass powder blended with zinc acetate salt, by flame spheroidisation method. The morphology and the microstructure of the samples were observed using SEM, TEM, FTIR and XRD techniques, whereas the composition of the feed glass and product HGMs were determined using EDX and ICP. The results showed that HGMs with surface coating of zinc oxide nanoparticles can be successfully synthesized using this single step process. Effect of zinc acetate percentage (0-10%) in the glass feed on the formation of zinc oxide coated HGMs and the nature of the ZnO coating were studied. A continuous thin coating of ZnO nanoparticles on the HGMs surface were obtained when the zinc acetate content in the feed glass powder was 2-5%. Further increase of the zinc acetate in the feed glass led to uneven coating on the surface of HGMs. A clear cut diffraction pattern for crystalline ZnO was observed at the thick patches observed on the HGMs samples with 10% loading of zinc. The thickness of the ZnO coating increased from 10 nm to 500 nm when the zinc content in the feed glass increased from 2 to 10%.

Abstract: A rhodamine-based fluorescent compound, spiro[1H-isoindole-1,9′-[9H]xanthen] -3(2H)-one, ′,6′-bis(diethylamino)-2-[(1-methylethylidene)-amino] (RB1), is developed to detect and inhibit the refractory steel corrosion in 3% NaCl solution. The inhibition effect was evaluated by electrochemical measurements. RB1 suppresses the cathodic corrosion reaction and shifts the corrosion potential toward more negative values. RB1 exhibits a turn-on fluorescence emission in the presence of Fe ³⁺ ions. The selectivity of RB1 over other commonly coexistent Cu²⁺, Fe ²⁺ and Mn²⁺ was investigated. The variation of the fluorescence intensity is correlated to that of weight-loss. RB1 has a potential application as corrosion inhibitor and corrosion indicator in some industry process.

Abstract: In this paper, we discuss experimental method of synthetic HTLcs by coprecipitation method,and factors of this HTLcs catalytic decomposition of methylene blue. Experimental results show that the Optimal catalytic conditions is: Catalyst is 0.75g/L, H₂O₂ concentration is 0.75% and Reaction time was2.5h when the initial concentration of methylene blue is 20mg/L and the PH value of solution is 2.The decolorization rate of Methylene blue can reach 96.56%.

Abstract: The surface properties of a commercial moso bamboo charcoal had been selectively modified by means of acidic treatment, using HNO3 with the concentrations of 17%, 34%, and 68% (w/w) respectively at 25°C for 8 hours. The iodine number, moisture content of all samples were tested, and the results showed that the iodine number of modified samples decreased slightly, while the moisture content increased sharply compared with raw sample, the sample modified with 68% HNO3 got the most remarkable change of above parameters. The Boehm titration、FTIR and SEM were also introduced to characterize the surface properties of raw and modified samples, the results revealed that the amount of surface functional groups, including various oxygen-containing and a few nitrogen-containing groups increased significantly of modified samples, the surface became more coarse and a large amount of fine fragment was yielded in pore space and vascular bundle of modified samples because of the corrosion behaviour of HNO3 in the modification process.