Advanced Materials Research Vols. 356-360

Abstract: Horseradish peroxidase was immobilized by montmorillonite to construct a nano-scale structural biocatalyst for the stabilization and/or detoxification of phenolic compounds from natural waters. Humic substances extracted from soils were used as a bonding agent, stimulating peptide covalent bonds between enzymes and surface of inorganic clay minerals. Operating conditions including concentrations of enzyme inoculated and duration time and temperature for the immobilization were examined and the optimal condition for maximizing the quantity of enzyme immobilized was found. The results of this study are expected to provide the essential information for the process-efficient and economic enzyme immobilization operations in the environmental engineering as well as for establishing ecological green U-City.

Abstract: Biochemical decomposition of catechol and 4-chlorocatechol, degradation intermediate products of 4-chlorophenol, was investigated using enzymes and their immobilized forms by clay minerals. An oxygenase that can initiate oxidative ring-fission of aromatic compounds was obtained via cloning of its gene (cphA-1) encoding hydroxyquinol dioxygenase contained in Arthrobacter chlorophenolicus A6 and overexpression and purification of the enzyme. The enzyme expressed in vitro was then immobilized onto the clay mineral (montmorillonite). Michaelis-Menten kinetic analysis was conducted to compare the expressed enzymes and the immobilized biocatalysts with regard to their degradation activity and capability to sustain activities under severe environments. Vmax values for the immobilized enzymes were smaller than those for the originally cloned enzymes, indicating that loss of enzyme activity was accompanied in the enzyme immobilization process. However, the immobilized enzyme demonstrated far more stable degrading activity in response to wide environmental changes such as marked variation of pH, temperature, and ionic strength. This supported that the enzyme immobilization can provide great advantages for its field application and also should be useful for establishing the concept of ecological green U-City.

Abstract: The influences of various geochemical factors, such as pH, phosphate, bicarbonate, humic acid, permanganate, and dissolved oxygen, on hexavalent chromium(Cr(VI)) removal by zero-valent iron(Fe⁰) were investigated in a batch setting. Results showed that low pH environments were favorable to removal of Cr(VI) compared with high pH environments. Phosphate significantly inhibited removal of Cr(VI) possibly due to competition of adsorption sites on corrosion products. Humic acid introduced a marginal influence on Fe⁰ reactivity toward Cr(VI) reduction, whereas bicarbonate enhanced Cr(VI) removal by maintaining the solution pH near neutral. Permanganate cumbered the removal of Cr(VI) due to its competition for electron from oxidation of Fe⁰. The removal efficiency of Cr(VI) was higher in oxic conditions than that in anoxic conditions.

Abstract: In order to observe the influences of liquid boiling time on purifying sugar from candied liquid with evaporation method, 50 g of candied liquid was weighed for evaporating experiments and control of the boiling time is 10 min, 20 min, 25 min, 30 min. In these experiments, 6 parallel experiments were done at each boiling time for observing the change of the candied liquid in different boiling time and determining the sweetness of candied liquid. The results show that: with the increase of boiling time, sugar content continue to decrease; Selected time for the purity of the purified sugar have a great impact.

Abstract: Preserved production is caused by wastewater pollution which has become a serious environmental problem in chaoshan district of one. Through the research KangHui group Chao’an cool fruit factory integrated nature of emissions from wastewater integrated wastewater, treat preserved fruits wastewater with activated sludge. In order to strengthen the cultivation of acclimation wastewater treatment, domestication was studied the best training domesticated aeration time. Experiments show that: The best treatment of preserved fruits wastewater is Acclimation of 38 h, and the wastewater CODcr removal rate reached 98.0%, then the effluent CODcr can be reduced in the 95 mg/L or so. Activated sludge treatment cool fruit production waste water, the training domesticated aeration and h of wastewater treatment after best effect.

Abstract: In order to observe the influence of liquid mass with evaporating purification from candied liquid of preserved fruits in the same boiling time, volume were obtained 35 g, 40 g, 45 g, 50 g, 55 g of candied liquid to evaporate. Boiling the solution for each time for 25 mins, the quality of each of four groups of parallel experiments was done to measure the candied liquid evaporation after sugar, the effects of different quality candied liquid evaporation effect. The results showed that in the same boiling time, the increase in quality with liquid, sugar becomes larger and larger; Candied liquid boiling temperature is about 99 °C, liquid in the different quality of candied sugar by evaporation and purification process need different times to boiling; In these experiments, candied sugar solution used was 60.8% of the percentage content.

Abstract: In this study, a mathematical model has been developed for the submerged membrane bioreactor (SMBR). Polyvinyl alcohol (PVA) Modified Non-woven model is immerged in MBR to be used for synthetic wastewater treatment. The results show that membrane fouling resistance is mostly cake resistance occurring during filtration. Based on the concept of specific fouling resistance and Darcy law that describes the relationship between flux and resistance during filtration driven by pressure, a module is established to explain the relationship between specific fouling resistance and time during filtration controlled by cake resistance in SMBR. The decline trend of flux can be predicted by the model. The model is used to predict the decline trend of flux during pharmaceutical wastewater treatment. Compared with experimental data, the relative error is less than 10% at t>b, the relative error is less than 5% at t>2b. It shows that the model can predict the decline trend of flux during stable operation of SMBR. But the relative error is bigger during unstable operation at initial stage (t

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