Advanced Materials Research Vols. 652-654

Abstract: Cyclic voltammograms were carried out to track the process of phenol electro-oxidation on GCE, understand the course and further guide the use in dealing with waste water. The effect of supporting electrolyte, phenol concentration, and scan rate were all tested. The results show that phenol oxidation contains several steps, and the first step is a mass transport process, while the following steps are not. What’s more, alkaline solution facilitates the first step, but the produced polymer can foul GCE and hinder the oxidation reaction in turn.

Abstract: Coagulation-flocculation process as an important water treatment technology has been widely used in the water treatment plant. The technology has been applied to the wastewater treatment, in general, by addition of a certain amount of chemical into the aquatic environment to make colloids destabilization and aggregation based on neutralization and adsorption bridging role. The conventional aluminum-based coagulant has been extensively studied. As a viable opinion, iron-based coagulant has attracted a wide attention. The objective of this research was aimed to investigate the preparation process of the iron-based coagulant using hydrogen peroxide as oxidizing agent. Parameters such sulfate dosage and hydrogen peroxide were analyzed. The results showed that a flocculant with the total iron mass percentage of 9.47 % and density of 1.43 g/mL was obtained. The flocculation test showed better performance.

Abstract: Starting with the research of the mechanism of treating organic wastewater, this paper found out various factors affecting electrode reaction, generation of hydroxyl free radical and flocculation reaction and the conditions promoting reinforcement of reaction, then associating with the advantage features of cavitation and impinging stream technology for degrading wastewater, it developed the "cavitation and impinging stream microelectrolysis technology", designed a novel structure of cavitation and impinging stream microelectrolysis reactor. In the technique of treating high concentration organic wastewater using microelectrolysis method, the problems of passivation and hardening can be solved by using this reactor with the features of high efficiency, environmental protection, safety, and good economics etc.

Abstract: Based on theoretical analysis and comparison, it is sure that urban rainwater collection and reuse have no negative effect on urban water circulation and downstream eco-environment. It is shown from the results that rainwater collection and reuse would not reduce volume of rainwater infiltration. It also could control runoff pollution and reduce the flood peak of downstream river in flood season. Thus, rainwater harvesting was an effective approach to improve the eco-environment of downstream river. It could be concluded that the technique could be applied to different areas to improve local conditions.

Abstract: Transition metal ion-doped titanium dioxide (TiO₂) powders were prepared by mechanochemical milling. Photocatalytic properties of the prepared semiconductor were evaluated using photodegradation of methylene blue under UV and visible light. Dye bleaching was observed spectrophotometrically. Color removal was reached after 120 min. The effect of varying concentration of organic dye, amount of TiO2 photocatalyst, particle size, pH, and stirring rate was observed on the efficiency of reaction. The maximum photocatalytic decomposition of methylene blue solution was achieved with 25nm particle size TiO₂, which was ascribed to the enlarged surface area. All obtained results were discussed.

Abstract: The object of this research is to investigate the removal of nitrogen in the form of ammonium ion (NH4+-N) from aqueous solutions using Na-form of high-performance ammonium ion-exchange material. The Chinese Kaolin from the province of Guangzhou is used as the raw material and modified to prepare the ion-exchange materials. According to CEC measurement, the obtained ammonium ion-exchange material had an ammonium ion exchange capacity greater than 75mgNH4+-N/g and can be used to remove ammonia nitrogen in water treatment. In this paper, several surface feature evaluation methods（SEM、XPS、IR）are used to discuss and analyze the modification process of kaolin and the action mechanism and modification results of the ammonia ion exchange material.

Abstract: It is very important that drawing up a reasonable developing and utilizing plan for water resources and ensuring the sustainable supply of water resources to the socioeconomic development of an area. So that, how to analyze and evaluate water resources carrying capacity is the key issue. In this paper, we proposed an evaluation method for water resources carrying capacity in Yellow River Delta based on projection pursuit evaluation model and particle swarm optimization. First, we regarded economy, social development, ecological environment and water resources as a compound system and established an index system including eighteen indices. Second, we chose the data in 2010 and evaluated water resources carrying capacity in Yellow River Delta utilizing projection pursuit evaluation model and particle swarm optimization. Finally, based on the evaluation above, we can draw a conclude for several areas in Yellow River Delta. The water resources carrying capacity of Dongying district and Kenli County is better and is at level II, and water resources are in week stress-free state. And that the one of Hekou district, Lijin County and Guangrao County is medium and level III, and the development of water resources and social economy is in coordination state.

Abstract: MoS₂、WS₂、Sb₂O₃ are common metal friction solid lubricants. Three substances can be complex preparation to create a new type of high temperature composite solid lubricant coating. We get the optimal ratio of such coatings through orthogonal experiment and explore the lubricating properties of the coating and find that the composite coating is good lubricity and wear resistance under high temperature conditions.

Abstract: The individual organic or inorganic ultraviolet absorbers contain absorption bands in different wavelength regions below 400nm, and the coupling of the two types of absorbers can improve anti-aging properties of coatings to prolong the service lifetime. Nanosized rutile and two typical commercial organic ultraviolet absorbers 2 - hydroxyl - 4 - n - octyloxybenzophenone (UV-531) and 2 - (3 - tert - butyl - 2 - hydroxyl - 5 - methylphenyl) - 5 - chloro - 2H - benzotriazole (UV-326) were coupled. Optical property of the hybrid ultraviolet (UV) absorbers was measured by UV-vis. The anti-aging property of polyacrylate coatings added with UV absorbers was carried out in a weatherometer and investigated by chalking and FTIR. The results show that hybrid UV absorbers have better performances of UV absorption with synergistic effects than both organic and inorganic components. In addition to improving the protection against UV, the coatings properties of adhesive, pencil hardness and stain resistance were increased by adding hybrid UV absorbers. The anti-aging mechanism of UV absorbers was analyzed.

Abstract: The Pb0.25Ba0.15Sr0.6TiO3 (PBST) thin films have been deposited on Pt/Ti/SiO2/Si substrates at different temperatures by radio frequency (rf) magnetron sputtering method. The microstructure, surface morphology, dielectric and tunable properties of PBST thin films were investigated as a function of deposition temperature. It’s found that the orientation of PBST thin films was adjusted by deposition temperature. The PBST thin film deposited at room temperature shows (100) preferred orientation and its dielectric constant and tunability are higher than that of PBST thin film deposited at 450 °C. Furthermore, the PBST thin film deposited at room temperature shows lower dielectric loss and leakage current, which makes it exhibit higher FOM of 49.47 for its appropriate tunability of 44.38% and low dielectric loss of 0.00897.