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Three Vibrio parahaemolyticus isolates 17802(tdh﹣, trh﹢, tlh﹢), 33846(tdh﹢, trh﹣, tlh﹢) and 05432 (tdh﹣, trh﹣, tlh﹢) were exposed to chloramine-T and sodium hypochlorite to investigate their susceptibility and resistance to chlorine-containing disinfectants. Results showed that sublethal disinfectant condition contributed to the formation of resistant strains, which minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were 2 folds higher than original strains. Differences were observed in physiological and biochemical properties between the original and resistant strains including growth kinetics, cultural character and biochemical characterizations, the resistant strains demonstrated higher lag phase than the original strains in the growth of tryptic soy broth (TSB) with adding 2.5% NaCl. They lost the abilities to grow in thiosulfate citrate bile sucrose（TCBS）media and chromogenic (CHROM) agar and to produce certain proteases such as lysine decarboxylase, ornithine decarboxylase and urease. The most significant change in biochemical characters of the strains was that the resistant strains could grow in the media without containing salts while the original strains could not.

The adsorption of two superplasticizers, SNF and CE, on the cement particles were investigated. The results shown that, the adsorption of the superplasticizers could be described with Langmuir isothermal adsorption equation. The saturated adsorptive capacity of SNF and CE was 11.35 and 5.24 mg/g at 20°C, respectively. The adsorption of SNF was faster than that of CE. When the concentration of superplasticizer was 1.0 g/L, the ζ potential of the cement surface with SNF was -28.8 mV, while that with CE was -20.6 mV, indicating that the electrostatic repulsive force of SNF was stronger than that of CE. XPS spectrum disclosed the thickness of adsorption layer of CE and SNF on the cement surface was 9.8 and 1.5 nm, thus the steric repulsive force of CE was stronger. The dispersion experiment displayed that, the dispersion capacity of CE on the cement paste was much better than that of SNF.

Stress relaxation constitutive equations based on Continuum Damage Mechanics, Kachanov-Robatnov creep model, and stress relaxation equation has been developed by analyzing stress relaxation damage mechanisms and considering the relationship that stress relaxation is creep at various stresses. And, the constitutive differential equations were integrated to predict stress relaxation performance by using numerical analysis technique. In order to validate the approach, the predicted results are compared to the experimental results of uni-axial isothermal stress relaxation tests conducted on 1Cr10NiMoW2VNbN steel with the same temperature of creep tests. Good agreement between results of relaxation tests and the predicted results indicates that the developed constitutive models can be used in the relaxation behavior evaluation of high temperature materials.

The paper analyzes the stress relaxation damage mechanisms of high temperature (HT) bolts of ultra-supercritical steam turbine units. Based on creep damage mechanisms and relaxation characteristics, the paper proposes a life prediction model, and by which to predict relaxation damage life of HT bolting material 1Cr10NiMoW2VNbN. Validation results indicate that the developed model has led to better consistent results with experimental data and thus can be recommended in relaxation life evaluation of HT materials.

Soft rot of Chinese cabbage is a common disease that causes serious damage and economic losses. In this study, the control on soft rot of growing and postharvest Chinese cabbage was carried out, using Harpin protein which was the expressed product of a recombinant E. coli strain. The experimental results indicate that Harpin protein preparation containing 3% pure protein powder and 97% wettable powder of Bacillus Thuringiensis (Bt), could effectively control soft rot of Chinese cabbage. The control effect on soft rot reached as high as 90% for growing Chinese cabbage using Harpin protein at 6-10mg/m2 of dosage, and the control effect reached approximately 75% for postharvest Chinese cabbage. Harpin protein stored for 6 months at 20-25 0C had the similarly biological activity with the newly prepared protein.

Biogas fermentation is always limited or affected at low temperature conditions, one of key factors may be physiological adaption of methanogenic communities to low temperature. Howerer, biogas process could be stimulated and enhanced with addition of enriched consortia. Here, six psychroactive methanogenic consortiums were enriched as additives, and consortium E-1 was found to be most effective at 150C. The total biogas production addition with E-1 improved 39.3 % and 17.0% from pig manure and cow manure, respectively, when decreasing from 210C to 150C, which is a potential microbial addition for biogas fermentation at low temperature.

Harpin protein was produced by a recombinant E. coli BL21(DE3)/pET30a(+)hrpNEcc in a 1-ton fermentor, and acute oral toxicity test in rats and guinea pig skin sensitization test for Harpin protein were carried out in order to determine its toxicity. The experimental results show that the protein production is up to 4.78 g/L after 16-18 h of fermentation, and the production cost of this protein is 1.75 yuan/g. Harpin protein produced by the recombinant E. coli strain is non-toxic (LD50>5000mg/kg) and has a low allergenicity (rate of sensitization is 0%). The results obtained in this study lay the foundation of the industrial manufacturing and the application on agriculture for Harpin protein.

Lactic acid (LA) production from food waste (FW) is a novel recycling method for organic solid waste. In this study, 35.12g/L LA produced from non-autoclaved FW by Lactobacillus bulgaricus, with a volumetric productivity of 0.98g/(L•h). The kinetic model of lactic acid formation in the FW fermentation at 45 0C and pH 5.5-6.0 was established. A nonlinear parameter estimation procedure was used to obtain optimal kinetic model parameters.