Advanced Materials Research Vols. 641-642

Abstract: TiO2 hollow spheres were synthesized through a facile bubble-template hydrothermal method. Microscopic and diffraction data indicated that the well-crystallized rutile-phase product was composed of self-assembly nanorods with an average diameter of 35 nm. The as-grown product showed high photocatalytic activities in degradation of organic pollutants such as rhodamine B under UV irradiation. It was found that almost all rhodamine B can be decomposed after only 30 minutes of UV irradiation. The enhanced photocatalytic performances were probably attributed to the structure of TiO2 hierarchical hollow spheres, which supplied higher specific surface area and faster electron transport.

Abstract: The purpose of this study is to recover molybdenum (VI) from aqueous solution with packed foam column by steady-state operation using hexadecyl trimethyl ammonium chloride as the surfactant. The parameters include air and feed flow rate, packing layer heights, surfactant concentration and pH etc, then the macroscopical dynamics is studied. The experimental results show that there are little effects of liquor pH, air flowrate and surfactant concentration on recovery rate and enrichment ratio of molybdenum within experimental conditions, but with increase of feed flow rate, recovery rate and enrichment ratio all decline clearly, with increase of packing height, recovery rate enhances evidently, and enrichment ratio decreases slowly. The macroscopical dynamics show that the process can be regarded as first order reaction. The fluid flow pattern is close to piston, indicating that there is little liquid backmixing and in favor of advancing separation efficiency by analyzing variance and distribution density function.

Abstract: The three-dimensional explicit dynamic analysis of metal cutting process is done using the non- linear finite element software LS-DYNA. In the finite element model, 8- node 3D solid element based on one- point integration Lagrangian formulation is adopted, metal material is modeled with Johnson-Cook constitutive model, chip separation is simulated using the material failure criterion of Johnson and Cook proposed and combing the failure element deletion method, friction model of chip-tool contact interface is developed to simultaneously account for sticking and sliding situation. Through explicit analysis, rake angle, cutting depth, and cutting width on the shape of the chip influence are obtained.

Abstract: This study has investigated the degradation of H-acid (1-amino-8-naphthol-3, 6-disulfonic acid) containing water by catalytic wet hydrogen peroxide oxidation method, in which the catalyst of Fe/SiO₂ was prepared by impregnation technology. The effect of catalyst dosage, initial pH value, amount of hydrogen peroxide and reaction temperature on the degradation process have been discussed, and the results indicated that wet hydrogen peroxide oxidation is an effective method for treating the wastewater containing H-acid, under the conditions that: catalyst dosage was 2 g, initial pH value was 7, amount of hydrogen peroxide was 10 mL (0.83 time of theoretical required amount) and reaction temperature was 80 °C, the COD and color removal rate can reach 87.3% and 96.5%, respectively.

Abstract: A non-P2O5 process to prepare ammonium polyphosphate is studied in this paper, the effect of raw materials is investigated. The XRD spectra of synthesized product are studied in detail. Results show that when the ratio of Mono-ammonium hydrogen phosphate to urea is 0.8:1, ammonium polyphosphate form V is the mostly occurrence. The results are informative for controllable preparation of APP in industrial production.

Abstract: This paper introduced the control of the electric loop on the hot strip mill. The loop mainly support the strip steel, form the loop variable which can adjust the dynamic speed of the mill, keep the pulling force of the strip steel between the framework, participate the speed control of the framework of the finishing rolling and the quality of the strip steel is ensured.

Abstract: In this study, granular sorbent (GS) which was prepared from red mud, clay and coal by sintering method was studied. With the aim of determining the optimal parameters for GS production, the influences of several important factors (including raw material ratio, sintering temperature and sintering time) on the adsorption capacity of GS for Cu2+ removal were evaluated in the single-experiment. The results indicated that the raw material ratio was the key factor that influenced the property of GS. The optimal conditions for GS preparation were as follows: the raw material ratio (red mud: clay: coal) of 85:10:5, sintering temperature of 400 °C and sintering time of 20 min.

Abstract: Hydrolysis acidification / pre-denitrification biological aerated filter was adopted in a domestic wastewater treatment plant. The effluent was accorded with a standard in the Integrated Wastewater Discharge Standard（GB18918-2002）, in which the effluent phosphorus was demanded below 0.5mg/L. Through analysis on the process biological phosphorus removal, biological method can be found to total phosphorus 1.5 mg/L. If you reach level to an emissions standards, phosphorus chemical experiment research, finally determined by strategy for the CN pool, point for adding potions FeCl3, dosing quantity for 35mg/L.

Abstract: A new FDM/ FEM model is developed to simulate the temperature field during the solidification process of squeeze casting. So we can transform the FDM mesh into FEM mesh directly ,then established the relationship of pressure change and melting temperature change and correct the size of melting temperature value and other thermal physical parameters (such as the thermal conductivity)which is related to the temperature ,and establish the temperature and thermal physical parameter relationship to get a data base. The solidification process of AM50A magnesium alloy is simulated. Squeeze casting experiments are also incited for validating the new FDM/FEM model. It is shown that the results of numerical simulation are in agreement with the experimental results.

Abstract: In this paper, according to the characteristics of squeeze casting solidification process, the calculation model (FDM format) of the partial differential equations with high thermal conductivity is used to the numerical simulation of temperature field. Dynamic isolated multi-molten pool judgment method is used to determine the position of the pool and FEM is used to calculate the pressure of pool center. If the pressure of molten pool center has been down to 0, the liquid metal closed in the scale will be solidification under the condition of no pressure, and will shrinkage based on the way of gravity shrinkage. The equivalent liquid surface descending method of isolated molten pool is used to predict the formation of shrinkage defect; the simulation result is coinciding with experimental data.