Advanced Materials Research Vols. 518-523

Abstract: The dielectric characteristic of fly ash is an important factor to influence the efficiency of electrostatic precipitators (ESP). By studying on the volt-ampere characteristic, the resistivity characteristic and the electric breakdown characteristic of fly ash burned coal, it is found that the relation among the voltage forced to the ash layer, the leak current flowed to the ash layer and the specific resistivity of fly ash does not always follow the classical ohm’s law, that is, V/I is not always constant. The volt-ampere characteristic curves of fly ash have different shapes while the voltage is in the different phases. Along with the voltage increasing, the specific resistivity is tending downward, and the range is less than 1 order of magnitude. Different fly ash has different capacity characteristic. And there are three methods to the breakdown of fly ash: the volume breakdown, the surface breakdown, and the interstice breakdown. The ways of breakdown is influenced with the particle characteristic, the surface characteristic and the electrostatic characteristic.

Abstract: A novel SO₄^2-/ZrO₂-NiO solid acid catalyst was prepared by using collagen fiber as the template. It was found that the SO₄^{2-//sup>ZrO₂-NiO catalyst remained good fibrous morphology by scanning electron microscopy (SEM). The IR analysis suggested that the metal oxide surface and SO₄2- were combined to form dual-coordinate state. The catalyst had both medium strong acidic sites and strong acidic sites through temperature-programmed decomposition (TPD) of ammonia. The calcination temperature is inversely proportional to the surface area of fibrous ZrO₂-NiO. The catalyst was applied to the esterification of acetic acid with n-butanol to estimate the catalytic activity and the best preparation conditions of SO₄2-/ZrO₂-NiO solid acid catalyst was found out. The results showed the SO₄2-/ZrO₂-NiO catalyst had high catalytic activity.}

Abstract: A type of visible light photocatalyst kaolin/Cu₂O was prepared from kaolin, CuCO₃·Cu(OH)₂·XH₂O, NaOH and C₆H₁₂O₆ by means of hydrothermal method and was characterized by XRD, SEM and UV-vis. The desulfurization process for model fuel was studied based on a combination of photochemical reaction and liquid-liquid extraction. The effects of the doping of kaolin, volume of air, reaction time, and dosage of photocatalyst kaolin/Cu₂O on the desulfurization efficiency were also investigated. When the load kaolin ratio of 20%, reaction time is 2 h, the volume of O₂ is 150 mL·min^-1, the amount of kaolin/Cu₂O is 2 g·L^-1 and solvent/oil ratio of 0.5, the desulfurization rate of model compound reached over 97 %.

Abstract: Kinds of pour point depressants were prepared from common monomers, octadecyl acrylate, maleic anhydride, styrene, acrylamide and vinyl acetate. Because the monomers have various functional groups, the performance of the polymers that were prepared from different monomers showed different. The performance of the pour point depressants on solubility in diesel and the drop of pour point on Daqing crude oil was studied. The results showed that styrene and vinyl acetate could increase the solubility of the pour point depressants; maleic anhydride and acrylamide could improve the drop of crude oil pour point; tercopolymer pour point depressants are more effective on the flow of crude oil than dimeric polymers, the highest drop of pour point was 14°C. Meanwhile, compostional pour point depressants are the best of them.

Abstract: Solubility studies of apatite in water and acidic media have been focused on the solubility products. Aim at highlighting on current developments, the solubility products of calcium arsenate-phosphate hydroxyapatite/fluorapatite [Ca₅(P_xAs_1-xO₄)₃(OH)/Ca₅(P_xAs_1-xO₄)₃ F, 1≥x≥0] in literature is sorted out. Literature values of the solubility products vary greatly. These discrepant solubility products can be due to differences between the minerals, the way the experiments in the studies have been conducted, the failure to achieve equilibrium.

Abstract: This paper introduces the concept of ecological environment material, its relationship with the society and its classification as well as application of several kinds of typical ecological environment materials. It points out that ecological environment material is one of the latest trends in development of material science and analyzes the current research trend of ecological environment material and Life Cycle Assessment (LCA) of materials.

Abstract: High specific surface materials were widely applied in water pollution control, air pollution control and recycling of organic solvents due to their excellent physical and chemical properties such as large specific surface area, redox characteristic, high adsorption and desorption speed and large adsorptive capacity. The characteristics of activated carbon fiber, nanometer titanium dioxide and their applications in environmental protection such as air purification, the treatment of drinking water and industrial wastewater and the recycling of organic solvent were investigated in present work.

Abstract: Using lightning location data of 9 stations in Hunan Province from 2007 and 2009, we analyze the lightning strength and frequency in Lishui bridge area and have a description of yearly and daily distribution. It shows that Lishui bridge regional lightning presented a mono-peak feature. Lightning mainly occurs from February to September, especially in August. Daily distribution here is extremely uneven. And lightning most happens in 6 a.m. and 4 p.m., which is different from most parts of China. Ground flash density near the bridge is 2.2 times /km2•a. Lightning intensity ranges from 25 kA to 65 kA. Strong lighting at 40-50 kA, even up to 200 kA, is more likely to take place. It has very important significance in choosing the lightning flow of surge protective devices.

Abstract: Based on observation of characteristics of NAI concentration of part of an office-building in Shenzhen, air quality of different equipments for cooling were assessed using ion polarity ratio (q) and air ion assessment index (CI). The result show that the air cleanness degree of the natural ventilation indoor is better than mechanical ventilation, using renewable energy for cooling is better than normal air-conditioning, and placed the negative ion generator has improved indoor air quality significantly. So the authors suggest to take NAI concentration as a monitoring and assessment indicators of the indoor environment, so as to provide a scientific basis and design concept for energy planning and environmental protection in the future.

Abstract: Elevator evacuation of high-rise building fire has become an urgent problem. Based on the problems of general elevator evacuation, this paper offers some measures of smoke-proof measures, such as setting up pressure ventilation in elevator car, setting up pressure ventilation in elevator shaft, setting elevator antechamber and setting smoke preventing air curtain etc. This paper provides some practical ways of elevator evacuation on high-rise building fire.