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Reclaim of large amounts of nitrogen oxides wasstudied which was produced in the production process of adipate in ChongqingChemical Industry Co. Ltd. The waste gas first was cooled, then into theabsorption tower through the compressor, most of the nitrous gas was absorbedout in the form of nitric acid after treated by three absorption towers. Weresearched gas composition at the gateway of recycling equipment by gaschromatograph, and which showed that all NO, NO2and nitric acid gas werealmost absorbed out, while N2O without being absorbed was eventuallyemissions into the atmosphere at the allowed concentration range. The research resultsshowed that could recycle 33,000 tons of nitric acid and saved 60 million yuan RMBfor the company every year after treating by the recycling equipment, whichfully embodied the economic value and environmental significance, and put out anew target of treating nitrous oxide gas.

In the context of global sustainable development, traditional wastewater treatment models reveal its shortcomings due to lack of recovering resource and energy in wastewater. Sustainable wastewater treatment technologies, taken wastewater as carriers of resource and energy, have been paid close attention. Starting from the existing problems of present wastewater treatment technology and focusing on the concept of resource recovery and energy utilization, this paper discussed the production technologies for hydrogen, electricity, diesel and methane from wastewater based on carbon resource recovery, and nitrogen resource treatment technologies with low energy consumption (such as shortcut nitrification-denitrification, ANAMMOX and SND). The latest research processes were also summarized. The research and development orientation of sustainable treatment technology for urban wastewater was put forward.

Marine adhesion organism includes biological mucosa such as marine bacteria, diatom, etc. and large adhesion organism such as mussel, barnacle, etc. Researches and analysis on adhesion mechanism of adhesion organism show that adhesion marine bacteria in biological mucosa will secrete protein-containing Polysaccharide polymer (PAVE) which can adhere to all kinds of surfaces. The reason is that in these secretions there is 3, 4-dihydroxyphenylalanine (DOPA) which is very viscous. Analysis on mussel, a large adhesion organism, shows that it is of super viscosity, which may result from its special molecular structure and the interaction way with substrates, and interstrand crosslink mediated by DOPA. DOPA plays an important role in this process. For marine bacteria and mussel, their viscosity is correlated with the generation and cross-linking of DOPA. On one hand, DOPA can enhance the viscosity of adhesion organism; on the other hand, it can improve the internal cohesion through cross-linking.

Using DFT/6-31+G (d, p) method, the structure of phenol are gained in the global optimization and properties were theoretically studied. The atomic electric charges, activation of reaction and thermodynamics parameters are obtained. The calculation shows that benzene ring in phenol tends to have electrophonic attacking substitution reaction O3 directly and form catechol and hydroquinol. The calculation of thermodynamics properties indicate that two pathways are exothermic reactions, and the Gibbs free energies (ΔG) are always less than zero, two reactions are easily occurred spontaneously. Dynamics calculations show that there is only one transition state in each reaction; through vibrational analysis we confirm the transition state. After corrected single point energy, we find that the reaction activation energies of the two reactions are small (Ea1=4.48kcal/mol and Ea2=2.87kal/mol), indicating that ortho-position and para-position products exist simultaneously, which is in accordance with the thermodynamics calculation result.

Adopting BYLP method in Density Functional Theory (DFT), we make theoretical study on the ozonide-orthophenylphenol, parachlorophenol, orthobenzoquinone and parabenzoquinone in the two reaction routes of phenol oxidizing into benzoquinone with ozone. We get the geometric configuration of molecules, charge distribution of atoms, thermodynamical properties and frontier orbit energy. Natural Bond Orbital(NBO)charge calculation shows that compared with orthobenzoquinone and parabenzoquinone molecules, phenol, orthophenylphenol and parachlorophenol molecules have stronger reactivity and they are more likely to have electrophilic substitution reaction. Thermodynamic properties indicate that phenol is easy to have oxidation reaction and produce orthophenylphenol which is easily to oxidize into orthobenzoquinone no matter at low temperature, room temperature or high temperature. Another reaction pathwaycalculation shows that in thermodynamics, phenol will not easily ozonize into parachlorophenol; while parachlorophenol will easily ozonize into parabenzoquinone. Frontier orbit energy calculation shows that phenol, orthophenylphenol, and parachlorophenol show similar stability. Orthobenzoquinone and parabenzoquinone have the strongest stability.