Advanced Materials Research Vol. 1058

Abstract: To save land resources by the use of low-grade natural resources to realize a high cost performance product, the technology of prepared superfine quartz sand powder via the ball milling methods were investigated. The results are shown the mean particle size of quartz sand powder is gradually become small varied with prolonging the ball milling time. Before 60 minutes, the mean particle size is slashed, however, the range of varying mean particle size is less after 60 minutes under the ball milling rotate speed for 200r/min and the charge amount for 200g/L, so the ball milling time for 60 minutes is decided.The mean grain size of quartz powders are decreased vary with an increasing the ball milling rotate speed, and the rotate speed is lower, the distribution is wider, however, the rotate speed is higher, the distribution is narrower.The mean grain size of quartz powders are 11.25μm via a roller ball milling, the mean grain size of quartz powders are 7.37μm via a planetary ball milling, and the particle size distribution of quartz powders milled via a roller ball milling is wider than that of quartz powders milled via a planetary ball milling, which shows the of quartz powders milled via a roller ball milling is not more uniform than that of quartz powders milled via a planetary ball milling, the asymmetry powder is advantage for forming the high performance building materials body.

Abstract: The sub-micrometre size platinum particles via chemical reduction of hexachloroplatinic acid in aqueous solution was investigated by UV-Visible Spectroscopy, Transmission Electron Microscopy, X-ray diffraction and FTIR Spectroscopy. Hydrazine hydrate was used as the reducing agent, and polyvinylpyrrolidone (PVP-K30) was used for stabilizing the particles. By varying the amount of PVP-K30 the average diameter of the platinum particles could be adjusted. The TEM and XRD results revealed that the final sub-micrometre size Pt particles were the result of an aggregation of small (~5 nm) nanoparticles. The UV-Visible Spectroscopy and FTIR Spectroscopy investigations indicates the mechanism of anti-aggregation of Pt particles by the steric effect of PVP-K30.

Abstract: Carbon-coated nickel nanoparticles were synthesized by solvothermal method in 1-buty-3-methylimidazolium tetrafluoraborate ionic liquid. The obtained products are characterized by X-ray powder diffraction (XRD), Raman spectroscopy, infrared spectroscopy and transmission electron microscopy (TEM). The magnetic properties of carbon-coated nickel nanoparticles have been investigated by vibrating sample magnetometry (VSM). It was found that the carbon-coated nickel nanoparticles showed excellent magnetic properties. The present route may give researchers more choices for preparing other carbon-coated transition metal nanoparticles.

Abstract: Different thickness multi-layer graphene were prepared by the method of liquid ultrasonic stripping and characterized by XRD, SEM and TEM. Friction and wear properties of graphene liquid dispersing system were investigated using an Multi-functional reciprocating friction and wear tester in ambient condition. Results indicate that the graphene were in thickness of 10nm-100nm. Multi-layer graphene showed good anti-friction and anti-wear properties as paraffin liquid additives. Multi-layer graphene liquid dispersing system had the best tribological properties with 20N and 0.01wt%, and the average friction coefficient was 0.129, and the wear mass was 4.12×106μm³, reduced by 21.34% and 41.14% than paraffin liquid. The reason is that Multi-layer graphene could adsorb on the worn surface and form solid adsorption layer, which maked the friction and wear reduce.

Abstract: In this paper, synthesis and fluorescence performance of graphene oxide have been primarily studied. Fistly, graphene oxide with remarkable fluorescence performance was prepared by modified hummer’s method. Secondly, changing the reaction time, the structure and size of graphene oxide were analyzed using X-ray diffraction (XRD) and Malvern Zeta-Size Analyzer, and the effects of different reaction conditions on the XRD patterns of graphene oxide were discussed. Finally, the fluorescence performance of graphene oxide solution were analyzed using fluorescence spectrometer.

Abstract: Wurtzite three-dimensional ZnS nanostructure has been synthesised under low temperature (180°C) via solvothermal method in mixed solvents of ethylenediamine and ethylene glycol. The phase structure, morphology and optical properties have been characterized by X-ray (XRD), scanning electron microscope (SEM) and photoluminescence spectra (PL). Through the change of reaction time and the mixed solvent ratio, the properties of three-dimensional ZnS have been discussed in this paper.

Abstract: BiOCl with 3D flower-like morphology was synthesized via a facile glycerol-mediated solvothermal method. The obtained products were well crystallized and subsequently characterized by a range of methods, such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED). The photocatalytic properties of the prepared samples were further investigated by photocatalytic decomposition of Methyl Orange (MO) dye. It is found that BiOCl hierarchical nanostructures exhibit efficient photocatalytic activities under UV light irradiation, which can decompose MO in a few minutes.

Abstract: Various hydrophobic groups were used to modify the silica membranes by the co-hydrolysis and condensation of 1,2-bis(triethoxysilyl)ethane and alkylsilanes. The hydrophobic property and surface roughness of silica membranes were characterized by water contact angle measurement and atomic force microscope, respectively. The results show that the hydrophobic property of modified silica membranes increases with increasing concentration of alkylsilane in the mixture, increasing surface roughness and increasing length of carbon chain in the alkyl groups.

Abstract: A modified coaxial electrospinning process is developed for producing medicated nanofiber membranes of shellac. With pure ethanol as a sheath fluid, high quality borneol-loaded shellac nanofibers have been successfully fabricated using the modified coaxial process. Electron scanning microscopic observations demonstrated that the nanofibers had better quality than those fabricated using a single fluid electrospinning in terms of nanofiber diameters and their distributions. The former had an average diameter of 570 ± 80 nm under a sheath-to-core flow rate ratio of 0.25, whereas the later was 940 ± 230 nm. X-ray diffraction results verified that borneol existed in the shellac matrix in an amorphous state. The medicated nanofiber membranes could significantly improved the physical stability of borneol due to the favorable hydrogen bonding between the drug and the polymer matrix, as demonstrated by the weight loss experiments. The modified coaxial electrospinning process described here expands the capability of electrospinning process in generating high quality functional membranes.

Abstract: Calcium phosphate cements (CPCs) have been widely used as bone substitute materials. However, their degradation property is insufficient to stimulate bone healing in large bone defects, besides, the poor initial mechanical strength limits their application to non-load bearing areas. In this study, to overcome the drawbacks of CPCs, magnesium phosphate cements (MPCs) characterized by high initial strength and relatively rapid degradation were combined with CPCs to develop novel calcium-magnesium phosphate cements (CMPCs). The morphology of the CPC sample consisted of needle-like crystals, whereas the interlinked hemispherical globules were observed for the CMPCs. The handling and mechanical characteristics of the samples as well as their degradation behavior under in vitro condition were investigated. Results showed that the CMPCs exhibited shorter setting time and higher compressive strength than the CPC. In addition, CMPCs showed significatnly improved degradability compared to the CPC in Tris-HCl buffer solution.