Research on Fluorescence Spectroscopy Characteristics of Dissolved Organic Matter of Landfill Leachate in the Rear Part of Three Gorges Reservoir

Three-dimensional fluorescence and infrared spectroscopy analysis of the leachate dissolved organic matter (DOM) of the Three Gorges was reported in spring, summer, and autumn seasons, respectively. Studies show that, that organic matter of landfill leachate in Yongchuan, Dazu and Jiangjin is the class of fulvic-like acid and protein-like fluorescence. The study also found that the longer the time of the pile of garbage, the lower the content of class of protein-like concentration, and the higher the concentration of fulvic-like acid, indicating that the protein waste material in the humification process is easy degradation. However, the same source of DOM is similar in the functional group composition and molecular structure. Characteristic frequency area analysis showed that humic acids (HA), and fulvic acids (FA) contain more than hydrophilic organic matter (HyI) aromatic ring structure, and FA aromatic ring structure is the most. Because of Chung-amide NH deformation vibration, there are strong absorption peaks in the 1562~1572 cm−1for various components; HyI contains many organic nitrogen compounds and fatty acids.

Study of Catalytic Cracking of Asphaltene in Near-Critical Water

The method of solvent division is adopted to separate asphaltene from Shengli heavy oil by n-heptane. 1HNMR and 13CNMR spectrum of asphaltene were determined with a Bruker Avance 400 NMR spectrometer. Combining with the elemental analysis results, the aromatic-ring structure is main structural composition in the asphaltene. Asphaltene was catalyzed and cracked with naphthenate nickel as catalytic cracking catalyst in near-critical water. The suitable reactional condition was obtained by orthogonal experiment method, reaction temperature 300°C, the mass fraction of catalyst used 0.6%, reaction time 24h. By testing element content of cracked asphaltene, carbon element content had reduced 0.06%~0.80%; hydrogen element content had reduced by 0.74%~3.41%; oxygen element content had reduced by 3.12%~27.1%; nitrogen element content had reduced by 0.40%~13.47%; sulfur element content had reduced by 9.85%~31.26%.

The Initial Dioxigenase Gene Squences Analysis of Marine Bacteria Strain M128

Biodegradation of polyaromatic hydrocarbons (PAHs) are catalyzed by multicomponent enzymes from microbe. The initial dioxygenase was used as a key enzyme for attacking the aromatic ring structure of PAHs, furthermore its initial dioxygenase gene was used to select PAHs degrading bacteria. Marine bacteria M128 strain could grow on medium contained PAHs. Detection of its cellular initial deoxygenase gene was done by nahAc gene amplification. The nahAc gene commonly used as biomarkers of PAH degradation, and as a result, nahAc gene sequence analysis of marine bacteria M128 strain was similar to naphthalene dioxygenase of Pseudomonas genera with 99% homology.

Kinetic studies on the reduction of cytochrome c. Reaction with dihydroxy conjugated compounds (catechols and quinols)

The kinetics of reduction of cytochrome c by catechol(s), quinol(s) and related compounds were investigated by stopped-flow spectrophotometry. Studies on the influence of pH on the rates indicate that only deprotonated forms of these compounds act as reducing agents, with the dianionic forms being the most effective. The pH-independent second-order rate constants are reported. Hammett treatment of the effects of substituents on the aromatic ring structure of the reductants show that for electron transfer to occur the charge on the deprotonated species must not be withdrawn on to the substituents. Possible sites for electron donation to cytochrome c are discussed, and the results indicate that the haem edge is a likely candidate.