Advanced Materials Research Vols. 550-553

Abstract: The quality safety of agricultural products play an important role in national economic development and social stability. This article introduced the agricultural products quality safety supervision information support technology, such as rapid detection and monitoring technology; the biological chip technology; agricultural products quality safety traceability technology; modern agricultural equipment and technology; vehicle positioning system; agricultural products quality safety inspection technology; technological choice index system; construction of the evaluation system. In the last part of this article it sent an agricultural products quality safety supervision information technology selection and evaluation, which means to use the scoring method to determine the index weight, technology index. And gave a table to introduce the vegetable quality safety supervision information technology selection index system in order to provide a theoretical basis with the perspective of industrial chain of vegetable quality safety supervision information technology and equipment integration.

Abstract: 5-hydroxymethylfurfural (HMF) and furfural (F) could be formed in soft beverages of rich sugar during process, and often used as an index of heat treatment. HMF was also considered as potentially carcinogenic to humans. High performance liquid chromatography was used to determine HMF and F contents of 26 soft beverage samples. The HMF contents were in a range 0.17-8.26 mg/L for 11 carbonated beverages, 0.37-22.23 mg/L for 8 fruit juice beverages and 0.05-1.63 mg/L for 7 tea beverages. The F contents were in a range 0.87-6.78 mg/L for 8 fruit juice beverages, but lower than 0.39 mg/L and 0.37 mg/L for 11 carbonated and 7 tea beverages, respectively. The highest contents of HMF and F were 22.23 mg/L and 6.78 mg/L. The contents of HMF and F in the group of tea beverage were the lowest among three groups of beverage samples.

Abstract: Plasma electrolytic oxidation (PEO) ceramic coatings were prepared on 6061 aluminum alloy substrate in silicate based electrolyte with and without Na₂WO₄ additive with different pulse frequency. The composition, surface morphology and corrosion resistance of PEO coatings were investigated by means of SEM, XRD, potentiodynamic polarization and EIS measurement in a 3.5% NaCl solution. These results show that Na₂WO₄ can contributing to the transition from the metastable γ-Al₂O₃ to a better thermal stability α-Al₂O₃, while has certain inhibitory effect on the deposition of SiO₃^2- anion on the surface during the plasma discharge process. After adding Na₂WO₄ in the electrolyte, the surface layer of PEO coatings are more smoother and less distinctly discharge holes appear which leads to the PEO coatings have better corrosion resistance than those of samples coated in the electrolyte without Na₂WO₄ additive.

Abstract: Three classical electrochemical techniques such as the pulsed potentiostatic method, cyclic voltammetry, and galvanostatic method were used to study the Ag morphology on glassy carbon disk electrode. The results of the three electrochemical methods were compared and the possible formation mechanism of fractal phenomena was discussed. It was found that cyclic voltammetry, and galvanostatic method are mild, convenient, fast and efficient method to prepare silver fractal structures.

Abstract: HfO₂ high-k dielectric films of 4nm and 5nm were both grown on Si substrate with the method of PEALD at 160°C. Both were treated with rapid thermal annealing (RTA) process at 500°C. High resolution transmission electron microscopy (HRTEM) indicated both films were not crystallized. X-ray photoelectron spectra (XPS) indicated that Hf-silicate was formed in the interfacial layer, and the valence-band offset (VBO) between the dielectric film and the substrate interface was calculated to be 3.5 eV. The electrical measurements indicated that the leakage current densities of the four and five nanometers’ sample were 1.0mA/cm² and 0.8mA/cm² at gate bias of 1V, and the equivalent oxide thicknesses of them were 0.9nm and 1.2nm respectively. Densities of interfacial states of them were calculated.

Abstract: Anodization of Zn foil in a salicylic acid-ethanol-H2O electrolyte and the following annealing of the anodized product have been investigated in this paper. Nano-porous metallic Zn were fabricated by anodization, and the Zn nano-pores formation mechanism on the zinc foil was suggested. The diameter of the Zn nano-pores is around 200 nm. Both the electrolyte concentration and potential have significant effect on the morphology and structure of the pores, and the nano-pores formation rate. Nanowire-like ZnO was produced by annealing the nano-porous metallic Zn obtained by anodization. The lengths of the ZnO nanowires range from 2 to 5 μm, and the diameters are in the range of 40~70 nm.

Abstract: Auric-cysteine complex[MAu(Cys)₄.xH₂O,M=K,NH₄,Na] was reported in this paper ,and its application in the electro-less plating was studied . By using single factor’s experiments the optimal plating index has been gotten and they are: pH=7~9,[Au]=1.5~3.5 g/L , temperature 40~60 Ċ, supporting ligand 0.1~0.15M and plating time 6~8minutes respectively. Related quality inspection of the plated panels show that the appearance, adhesion power and gold thickness can meet the standard of the modern industry .

Abstract: This paper described the liquid flow battery system with graphite felt electrode and a single electrolyte, lead(II)in methanesulfonic acid. The kinetics and cyclic voltammetry behavior effects of PbO₂/Pb(II) couple were studied. The results show that the equilibrium electrode potential PbO₂/Pb(II) couple with good kinetics behavior was 1.21V. The cyclic voltammetry behavior of PbO₂/Pb(II) couple on graphite felt electrode was studied, and the oxidization and reduction peak potentials were 1.547V and 1.241V, respectively. The graphite felt treated with sulfuric acid showed good electro-catalytic activity for PbO₂/Pb(II) couple.

Abstract: Orthogonal test was used to optimize the electrodeposition process of PtRu catalysts for methanol electro-oxidation. The morphology, composition and catalytic activities of the prepared catalysts were measured by scanning electron microscope (SEM), energy dispersive X-Ray spectroscopy (EDS) and cyclic voltammetry (CV). The results show that the optimum electrodeposition conditions are: the concentrations of H₂PtCl₆ and RuCl₃ of 2.5 mM, the concentration of H₂SO₄ of 0.1 M, the electrodeposition potential of -0.25 V vs SCE, and the electrodeposition time of 10 min. Under these electrodeposition conditions, the prepared PtRu catalyst demonstrates excellent catalytic activity for methanol electro-oxidation.

Abstract: In this paper, advanced Fenton-hydroxide precipitation process was proposed to remove synthetic wastewater containing CrEDTA. This process can not only remove chromium, but also reduce COD values. Parameters affecting chromium removal are discussed. At optimum conditions, the chromium removal efficiency attained 87%. Advanced Fenton-hydroxide precipitation process appears a promising and effective method for the treatment of strong stability complex heavy metal containing wastewaters.