Advanced Materials Research Vols. 941-944

Abstract: A series of CuO–ZnO–ZrO₂ (CZZ) catalysts with different Zn/Zr ratios were successfully prepared by the co-precipitation method and characterized by the techniques of X-ray diffraction (XRD), N₂ adsorption, reactive N₂O adsorption, H₂ temperature-programmed reduction (H₂-TPR). The catalytic activities of the catalysts were tested for methanol synthesis from CO₂ hydrogenation. It was found that the increasing of the Zn/Zr ratio could lead to the increase of the crystallite size of metallic oxide. When the amount of ZnO ranged from 20% to 80%, the CZZ catalysts exhibited a better activity. It revealed that both Zn and Zr were important parameter for Cu-based catalysts, which were interacted with each other.

Abstract: This work concern the research of the concentration dependences of the influence the micro amounts of the fine disperse silica fume and the carbon nanoparticles containing modifiers on the mobility of the fine-aggregate concrete mixtures and on the pressure strength of concrete. It was founded the high nonlinear dependences of increasing this parameters in the region of the concentration 10^-3 – 10^-6 % of the mass of concrete. This results provide the possibility to approach the industry application for the high performance concretes technology at the nearest time.

Abstract: The EP/TiO₂ nanocomposites were prepared by using epoxy resin as matrix, nanoTiO₂ as the modifier, polyamide as curing agent. The surface morphology of nanoTiO₂ was observed,the average particle diameter of nanoTiO₂ is 20nm. Their mechanics properties were studied and the experiment results were analyzed. The results indicated that the compressive stress-strain curves of the nanocomposites had obvious three phases characters, i.e., linear elastic phase, plastic yield flat phase and compact phase. Along with the nanograins content of the nanocomposites increasing, the compressive elastic modulus and compressive strength of the nanocomposites augmented. When the nanograins content is 5% and the transfiguration speed is 10mm/min, the compressive elastic modulus and compressive strength of the nanocomposites respectively improved 49.2% and 45.2% comparing with their of the pure epoxy resin. At the same nanograins content, with the transfiguration speed increasing, their compressive strength added.

Abstract: This paper gives an overall review of TiO₂ nanotube arrays synthesized on titanium and its alloys substrates by anodization. The highly ordered nanotubes are fabricated by electrochemical anodization in electrolyte containing fluoride ion. During the anodization process, the electrochemical conditions such as the electrolyte, applied voltage, anodization time, temperature and alloy substrates are analyzed in detail. Anodization of titanium alloy is a simple and effect method to dope element into TiO₂ nanotube which shows much higher improvement in photocatalytic and solar energy conversion than pure TiO2 nanotube arrays. In addition, we review the forming mechanism and modification. Furthermore, TiO₂ nanotube arrays have great application for dye-sensitized solar cells, water splitting and biomedical and other aspects.

Abstract: The regenerated liquid reactive dye Regenerated Magenta had been prepared with the waste reactive ink of Jettex R Magenta in the process of digital inkjet printing. The effects of quality percentage of waste ink, cosolvent, pH regulator on the stabilities of Regenerated Magenta had been investigated. The results show that the Regenerated Magenta ink prepared with waste ink 26%, N-methyl-2-pyrrolidone 4%, THAM 1%, ethanediol 3% and deionized water 67% has good performances such as particle sizes, surface tension, viscosity and conductivity. The characteristics of Regenerated Magenta ink meet the demands of the ink for digital inkjet printing.

Abstract: Organic aerogels were prepared by sol-gel polycondensation of resorcinol and formaldehyde using sodium carbonate as a catalyst and dried under ambient pressure. Carbon aerogels were obtained by the dried organic aerogels carbonized under nitrogen atmosphere at high temperature. The pore structures and surface characteristic of the carbon aerogels obtained were investigated by N₂ adsorption isotherms, scanning electron microscope (SEM). Through controlling the concentrations of the main ingredients (resorcinol and formaldehyde), catalyst concentration, we can find out the best concentration which the specific surface area can reach the highest. In this experiment the highest specific surface area was 1645m²/g. In addition, the results show that catalyst for the cross link effect between colloidal microspheres is greater than the growth of the colloid itself, and the effect of water solvent plays an important role in the density of carbon aerogel.

Abstract: Article is devoted to studying of influence of additives on rheology of the nanostructured modifier on the basis of silica-containing raw materials. Optimum technological combinations of the plasticizer were defined, which allow to change flow character of a suspension and to give to a material necessary properties. Basic possibility to use additives on a melamine-formaldehyde basis for plasticization of the nanostructured modifiers of silicate structure is proved.

Abstract: MgB₂-based superconducting composites with magnetic nanoparticles were fabricated by spark plasma sintering technique. Two methods have been used to create nanoparticles within MgB₂ matrix: i) direct insertion of passivated magnetic nanoparticles; ii) growth of magnetic nanoparticles by thermolysis of polymers or metallo-organic precursors. These composites display an enhanced critical current density due to the additional magnetic pinning generated by the magnetic interaction with the flux lines.

Abstract: Nanometer Al₂O₃ particles reinforced 7055Al composites were processed by high magnetic field with 2T,3T and 4T magnetic induced intensity (B) with constant 30 pulses. Transmission Electronic Microscopy (TEM) and X ray diffraction (XRD) were mainly used to analyze some characteristic of the treated samples. The results show that with the increase of B the dislocation density was enhanced apparently. It is deduced that plastic deformation was the main reason of high density dislocation. The magnetoplasticity effect was the source of plastic deformation.

Abstract: In this paper, multiphase composite Al₂O₃ ceramics including carbon nanotubes was fabricated by hot pressing sintering. And researching and analyzing the influence of different volume fraction of carbon nanotubes for the microstructure of multiphase composite Al₂O₃ ceramics by SEM.