Applied Mechanics and Materials Vols. 178-181

Abstract: A new heteropoly salt with Keggin structure of the 1:1:11 series had been synthesized, and characterized the structure by the foruier transform infrared spectroscopy (IR), ultraviolet spectra (UV) and X-ray diffraction (XRD).The thermal stability and the number of the crystal water was analyzed by the thermal gravimetric analysis/differential thermal analysis (TG/DTA). It was showed the molecular formula was Na₆[Ni(ZrMo₁₁O₃₉)]•20H₂O( Abbrev.NiZrMo),it possessed Keggin structure and had good thermal stability. The influences on the degradation rate, such as the amount of the NiZrMo, the initial concentration of the AGB dye wastewater, the ultrasonic frequency and power, were investigated. The results showed that the degradation rate could reach 90.19% after 60min irradiation, when the amount of the NiZrMo was 0.8g•L^-1, the concentration of the AGB was 10mg•L^-1, the ultrasonic frequency was 40kHz and the ultrasonic power was 80W.

Abstract: The field in which pure oxygen aeration is applied to sewage treatment is extensive. In actual application it is more suitable for the degradation of industrial sewage. Pure oxygen aeration has unique merit compared with common air aeration. This article introduced the effect by pure oxygen aeration. The study shows pure oxygen aeration is an effective pollutant removal mechanism, and at the same time proposes the best dissolved oxygen is at 3 mg/l. The average removal rates of COD_cr, NH₃-N, TN are 73%, 50%, 55% respectively. The conclusion is that pure oxygen aeration for hospital wastewater the CODcr removing rate is higher than ammonia nitrogen and total nitrogen efficiency.

Abstract: Municipalsludge is refers to the product of sewage treatment plant, facing the huge number of municipalsludge, the disposal of the municipalsludge has aroused wide attention of all countries. Many studies consider that urban land use of the municipalsludge is the most effective method, However heavy metal accumulats in the sludge and the environment of the risk with agricultural appears day after day.The purpose of this study is: analysis the transfermation of heavy metals in the activated sludge system of various structures. put forward the solution of reducing heavy metal exceeded in the activated sludge treatment process.It appears that the coagulation can make colloid stabilized and sedimentation, can control the input of the heavy metal effectively; Adsorption of activated sludge to heavy metal is very fast, in 30 min basic reached adsorption balance, probably 80% or more;The change from oxygen to aerobic have great influence on Heavy metal biological adsorption;An aerobic digestion processes can reduce the volume and quality of sludge, but there is no enrichment role to heavy metal in sludge.

Abstract: Contrasting《Discharge standard of water pollutants for pulp and paper industry》(GB3544-2008) to《Discharge standard of water pollutants for pulp and paper industry》(GB3544-2001), this article educes impact for pulp and paper industry by 《Discharge standard of water pollutants for pulp and paper industry》(GB3544-2008). This article discuss producing technics and dealing with waste water technics of pulp and paper industry, that satisfy GB3544-2008.

Abstract: In this paper, parallel flaw precipitation method has been employed to fabricate nanostructured Bi₂O₃. It is found that the surface parameters, bandgap, the photoinduced charge separation rate and photocatalytic performance of Bi₂O₃ have a strong dependence on the pH value of precipitation reaction.The prepared photocatalysts were characterized by BET, XRD, UV-Vis diffuse reflectance and surface photovoltage spectroscopy (SPS). The results show that Bi₂O₃ prepared under pH value10.0 exhibits the best photocatalytic activity among the experimented compositions. The results of further experiments show that surface parameters, bandgap, the photoinduced charge separation rate all play an important role in promotion of photocatalytic activity of Bi₂O₃ prepared under pH value 10.0.

Abstract: It has been found that the photocatalytic activity of Bi₂O₃ toward the decolorization of Methyl Orange solution can be greatly improved by loading Ag on the surface of Bi₂O₃ using a photodeposition method. The photocatalysts were characterized by X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy and surface photovoltage spectroscopy (SPS), respectively. 0.5%Ag/Bi₂O₃ possesses the best photocatalytic activity.

Abstract: In this paprer, ZnO was loaded on SiO₂ by sol-gel method. The prepared photocatalysts were characterized by BET, XRD, UV-Vis diffuse reflectance spectroscopy and surface photovoltage spectroscopy (SPS). The paper reveals that the photocatalytic activity of ZnO towards the decomposition of methyl orange can be greatly improved by loading ZnO on the surface of SiO₂. 80% SiO₂ possesses the best photocatalytic activity among the experimented compositions.

Abstract: This report has shown that the dye of Methyl Orange (MO) in water can be decolorized effectively in the presence of KIO₃ under UV irradiation. Decolorisation efficiency of MO increases as the loading of KIO₃ increases and has no an optimal amount of KIO₃ in this case. The kinetic result shows that the decolorisation reaction is a pseudo first-order reaction when the concentration of MO is below 10 mgL-1. The influences of the pH value and hydroxyl radical scavengers on the decolorisation reaction were investigated in detailed. Several observations indicate that the mechanism is not the attack of hydroxyl radicals in MO decolorisation with KIO₃ under UV irradiation. More considerations should be focused on the underlying possible decolorisation mechanism of MO with KIO₃ under UV irradiation.

Abstract: Magnetic Cu²⁺-chelated silica particles using polyacrylamide (PAM) as a metal-chelating ligand were developed and used for the immobilization of laccase by coordination. The particles were characterized by (XRD). The effect of Cu²⁺ and PAM concentrations on the enzymatic activity and the catalytic capacity for pentachlorophenol (PCP) degradation were evaluated. The results showed that the optimum Cu²⁺ and PAM concentrations were 0.2 mol/L and 2 g/L, respectively. The immobilized laccase prepared in this work exhibited a good catalytic capacity for PCP removal from aqueous solutions.

Abstract: Based on the characteristics of urban slow-flow water body, the article analyzed the current situation and pollution problems of urban slow-flow water body in Zhengzhou city. The countermeasures such as reasonable planning, enough ecological water, application on habitat improvement technology of urban slow-flow water body, strengthening supervision, and enhancing environmental awareness education were posed.