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In this study, three bio-electrokinetic remediation experiments were carried out to study the external delivery of oil-degrading bacteria by electrokinetics and enzyme activities in saturated soil. Results showed that the oil-degrading bacteria could efficiently transport to the saturated oil-contaminated soil by electrophoresis and/or electroosmosis. Bacterial population increased from 6.02-7.75 log (CFU/g) in the control experiment to 8.53-12.83 log (CFU/g) after external bacterial delivery. Under unidirectional operation, the bacterial populations near the electrodes were lower than those in the middle of the soil as a result of unfavorable pH environments. In bidirectional experiment BEK-B, a relatively low bacterial population in the middle of the soil was observed after the experiment. The activities of catalase, polyphenol oxidase, and dehydrogenase have similar trends with bacterial population in the soil, indicating a good relation between the three enzymes and oil biodegradation of oil in soil.

Bio-electrokinetic remediation of oil-contaminated soil is a promising technology. In this study, three bio-electrokinetic remediation experiments were carried out to study the effects of external addition of oil-degrading bacteria by electrokinetics and different operational parameters on oil decontamination in saturated soil. Results showed that oil in soil migrated from the anode towards the cathode with forward electroosmotic flow and accumulated near the cathode. Oil was barely degraded without external addition of oil-degrading bacteria. Although electrolytes were refreshed every 12 hr, soil pH varied greatly at the electrodes under unidirectional operation. When electrode polarity was reversed every 2 hr, soil pH was efficiently controlled within the range of 6.35-9.75. The relative oil concentrations after the bidirectional experiment were in the range of 0.81-0.84 after 20 days of treatment. The relatively low oil degradation rate may be due to the facultative aerobic environment in the saturated soil matrix.

A comprehensive molecular simulation study on heterogeneous reaction mechanisms of NO with nitrogen-containing char is carried out using density functional theory. NO chemisorption and subsequent possible reaction pathways are proposed. Geometries of reactants, products, stable intermediates and transition states are optimized at B3LYP/6-31G(d) level. It is found that NO molecule chemisorption with its bond axis parallel to the edge line of nitrogen-containing char is a weakly exothermic process. The N-O bond in NO molecule tends to dissociate after chemisorption. N2 and CO are desorbed when NO molecules are chemisorbed with the formation of N-N bond. N2 desorption is exothermic, while CO desorption is endothermic. So we conclude that N2 is the dominant product from interaction between NO and nitrogen-containing char.

A Ce-Zr-Ti composite oxide catalyst was prepared by the sol-gel method and its NH3-SCR activities were investigated. The Ce-Zr-Ti oxide catalyst exhibited high activity and 92.7-98.8% NO conversion was obtained in the temperature range 250-450 °C at the high gas hourly space velocity of 50,000 h-1. In comparison with Ce-Ti oxide catalyst, the Ce-Zr-Ti oxide catalyst showed strong resistance to H2O and SO2. The excellent performance of the Ce-Zr-Ti oxide catalyst might be attributed to the large surface area and strong interaction among the three elements of Ce, Zr and Ti.

In this paper, a novel light-absorpting shade and optical fiber and long persistent luminescent phosphor materials provided a safe and reliable day-and-night solar lighting system. It was not only save resource, reduce pollution, at the same time introduced solar light into the indoor to satisfy the lighting needs. The novel light-absorpting shade fabricated nanodiamond film to achieve the goal of self-cleaning,corrosion-resistant and corrosion-high temperature. This novel solar lighting system used of total reflection characteristic of optical fiber, and long persistent luminescent phosphor materials short storage time, high brightness to realize the purpose of day and night lighting.

This paper present the optimum conditions for treating oily sludge with organic solvent extraction and surfactant solutions using the single factor experiment. Firstly, selecting petroleum ether (boiling range is 60-90oC) as the organic solvent, then selecting the mixture of sodium dodecyl benzene sulfonate and alkylphenol ether(OP-10) as surfactant agent to extract residual crude oil. Results obtained through experiments, the optimum parameters of petroleum ether were that ultrasonic reaction temperature was 55 oC, ultrasonic intensity was 320W, ultrasonic extraction time was 5min, liquid/solid mass rate was 7.5, then under the optimum conditions, the residual oil rate was about 6%. While the optimum parameters of surfactant mixture were that the temperature was 55 oC, ultrasonic intensity was still 320W, ultrasonic extraction time was 10min, liquid/solid mass rate was 15, under the optimum conditions, finally the residual oil rate was only about 1%.

Nano-SiC was mixed with nanocrystalline graphite and ethylic cellulose to paste. In order to fabricate Nano-SiC film electrode of super capacitor, a series of sol-gel Nano-SiC film with different proportions are designed test intentionally. Nano-SiC film was fixed on metal substrates using three-steps sintering process. The perovskite structure CaCu3Ti4O12 (of CCTO) ceramics has giant permittivity, low dielectric loss, good thermal stability and dielectric constant in a wide temperature range has very broad application prospects in microelectronics. In this paper, the solid state reaction sintering can be divided into two categories: sintering at 1373K at different times; first heating to 1423K then immediately cooling to 1373K and keeping for different times. The CCTO ceramic dielectric constant and dielectric loss decreased with frequency rises. A super capacitor was designed based on CCTO ceramics dielectric and Nano-SiC film electrode.