Applied Mechanics and Materials Vol. 709

Abstract: We present the synthesis of ZnO nanostructures grown by the hydrothermal method using the rapid microwave heating process. First, 10 mM solutions of zinc acetate dihydrate and 1-propanol were three cycles spin coated on glass substrates at 2000 rpm by 70 s, 90 s and 90 s, respectively. Second, nanostructures were then grown by dipping the substrates in a solution of zinc nitrate hexahydrate, polyethyleneimine (PEI), hexamethylenetetramine and ammonia. The hydrothermal process were carried out with a commercial microwave at 300, and 600 W power settings during 20 min. The structural and morphological properties were investigated using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The influence of the ammonium concentration in the morphology of the nanostructures was analyzed.Keywords: ZnO, nanostructures, XRD, SEM, spin coating, ammonium, hydrothermal process.

Abstract: This study aimed to explore a new perovskite-based color pigment system. The Cr:SrTiO₃ pigments were in the 350 nm range. A solid solution could be obtained at high calcination temperatures as confirmed by both structural and optical characterization. A secondary phase of SrCr₂O₇ was detected at high Cr doping, suggesting a possible complicated nature of Cr species techniques. Shifting of the absorption edge toward the visible range was also observed. The pigments were found to be evenly distributed in the glaze. The synthesized pigment powders were initially brown-maroon and gradually changed to the red and yellow tones when incorporating with the glaze.

Abstract: Photo-and radioluminescence characteristics of Ce³⁺-doped dense oxide glass (SiO₂-B₂O₃-Al₂O₃-Gd₂O₃) are presented. The Gd³⁺→ Ce³⁺ energy transfer was evidenced by photoluminescence excitation spectra of Ce³⁺ emission. Photoluminescence decay kinetics was governed by a few tens of nanoseconds decay time. The integral scintillation efficiency of about 22% of that of the Bi₄Ge₃O₁₂ scintillator was obtained under X-ray irradiation. Scintillation light yield under alpha particle excitation was measured and compared with that of the Bi₄Ge₃O₁₂ crystal.

Abstract: To study the difference of pavement performance between DAT warm-mix asphalt and hot-mix asphalt, the impact on the SBS asphalt with 10% DAT was studied first. Then AC-5 asphalt mixture was made the Marshall specimens according to the indoor mixing and molding temperature. Analyze the road performance between warm mix asphalt and hot mix asphalt. The experiment results show that the SBS asphalt with DAT has small difference to the original. The DAT warm-mix asphalt has poor water stability and low-temperature stability but good high-temperature stability than the hot mix asphalt when the indoor mixing and molding temperature has 20°C reduction. So DAT warm-mix asphalt can achieve the purpose of energy saving.

Abstract: Copper (II) oxide clusters (CuO)_n with n = 1 – 4, 6 have been calculated by DFT method with the exchange-correlation functional B3LYP. The structural, energy and electronic properties have been studied. Much attention was given to the interaction between CO and active centers of the clusters. The most probable orientation of CO on the metal oxide surface has been determined and the stability of clusters has been evaluated.

Abstract: This paper describes the process of biomass pyrolysis to make biochar briefly. Studied the biochar production rate and composition and content of gas under different conditions of temperature and residence time. Meanwhile, the heating value of the combustible gas produced was analyzed. The results showed that: temperature, residence time both have different influence on the pyrolysis process Also proved that 450-500°C is not only the best temperature for biochar production,but the highest heating value of the combustible gas.It can provide the basis for the furter study of accuracy control and online monitoring of biochar production and improvement of the carbonization furnace.

Abstract: The study of the mixing method, mixing time, waste rubber powder as the amount of waste rubber powder by resorcinol (R) and six methyl four amine (H) effect on the mechanical properties of waste rubber powder /NR blend modified. The results show that, with effect of blending method, mixing time and waste rubber powder content on mechanical properties of blend vulcanizate; through modification, can greatly improve the mechanical properties of waste rubber powder blend vulcanizates, as the modifier of resorcinol and six methyl four amine mass ratio was 1/0.5, glue the material mechanical properties are the best, the tensile strength is 17.03 MPa.

Abstract: Injection molding is one of several molding technology of microcellular foamed plastics. This paper mainly discusses the injection molding mechanism and applications of microcellular foamed plastics here, and analyzes the influence of microcellular foamed plastics injection molding process parameters, including injection pressure, melt temperature, injection time, etc.; At the same time, this paper makes a more systematic discussions for the injection molding technology of microcellular foamed plastics, and the typical cases of microcellular foamed plastics in engineering application are introduced in detail.

Abstract: Introduction of fine rubber powder use, production process and production equipment. In rubber industry for direct forming or rubber and rubber for; modification and applications in non rubber industry rubber powder mainly into the plastic and asphalt materials. Fine rubber powder production process includes dry grinding, wet grinding, cryogenic grinding and the physical and chemical method. The main equipment, rubber powder production is often cold mill or screw extruder.

Abstract: Using vitamin C or ascorbic acid as corrosion inhibitor has several weakness. In its liquid form ascorbic acid is easily oxidized and its anti oxidant properties unstable due to heat, light, oxidizer, dissolved oxygen and heavy metals. Purple sweet potato (ipomoea batatas L) with its high anthocyanin is one of alternative for green corrosion inhibitor. Extract of purple sweet potato has the ability to hold the enzyme reaction and oxidation proses of ascorbic acid. Purple sweet potato extract mixed with ascorbid acid is used as inhibitor of API 5L steel in 3.5%NaCl. This compound is classifid as mixed type inhibitor. The adding of purple sweet potato extract will assist ascorbic acid to maintance its inhibition efficiency and increases surface layer corrosion resistant of steel. Polarization methods and electrocehmical impedance spectroscopy (EIS) are used to investigate corrosion rate and mechanism of the steel. Appliaction of 4 ml purple sweet potato mixed with 10^-4M ascorbic acid inhibitor increases inhibition ability of API 5L steel from 23.5 to 57.52%. Purple sweet potato extract moves polarization curve to lower potential (below 82 mVolt) with tends to be more negative.