Advanced Materials Research Vols. 356-360

Abstract: The tetracycline (TC) adsorption on the graphite was investigated by method of static experiments. Related properties of the adsorbate and adsorbent were studied to support the adsorption mechanisms exploration. The results indicate the close relationship existing among the adsorption capacity variation, TC K_ow and TC species (+,-,0) distribution on pH. And the hydrophobic force drives TC adsorption on the graphite.

Abstract: This paper presents a systematic study of the biometric leaching sequencing batch experiment. The major process parameters include the inoculation amount of bacteria(5%) and substrate concentration(4g/L)(elemental sulfur). The chemical speciation transformation takes place in Biology leaching were measured by sequential extraction techniques. Through which before and after the leaching we can Analyze the filter mechanism and leaching ability. According to Cd, Pb content of each chemical speciation before and after the leaching, the release rules of different chemical speciation for each elements in every sampling period were calculated. This paper also analyzed the leaching ability of different chemical speciation in different leaching condition. The results indicated that,Cd drains out through the indirect mechanism, Pb drainings is mainly completes by direct machine-made and the indirect mechanism combined action.

Abstract: Advantage strains SRB and V.natriegens were obtained from the China East Sea for this study. Polarization curves, corrosion potential, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analyses were adopted in order to investigate the corrosion behaviors of 0Cr18Ni9 stainless steel under the combination action of anaerobic SRB and facultative anaerobic V.natriegens, The characteristics and mechanisms of microbial corrosion action in sea water were analyzed in this paper. The results show that SRB and V.natriegens promote each other’s growth when cultivated in the mixed microbe medium, in which the rate of corrosion is higher than that in the single microbe; Under the combined action of the mixed microbe, the microbial film gets wider and thicker, and corrosion products and metabolite are produced, which furthermore accelerates the passivation and pit corrosion to the 0Cr18Ni9 stainless steel.

Abstract: In Hainan ChengMai Kudingcha Plantation, soil, roots, leaves of Ilex kudingcha C. J. Tseng were obtained from 11 sampling points as “S” and analyzed for Cd and physical and chemical properties of soil, then the concentration and mobility of Cd in tea trees-soil was studied. The speciation of Cd in soil were analyzed by BCR three stage sequential extraction procedure and one-step extraction. Method characterized Bioavailability of Cd in Ilex kudingcha C. J. Tseng were established through the correlation analysis of Cd speciation in soil to Cd content in leaves and the influence of physical and chemical properties of soil to Bioavailability of Cd in soil was discussed. Results of this study showed that: The majority of Cd in soil was transferred to plant as the strong enrichment of Ilex kudingcha C. J. Tseng Trees, The Cd content distribution was: roots > leaves >>rhizosphere soil; According to the correlation analysis, （F1）、（F1+F2） and Cd-HCl extraction were used to characterize the Bioavailability of Cd in soil due to complex soil environment. The order of physical and chemical properties of soil which affected Bioavailability of Cd was: pH>Eh>organic matter>moisture>volatile phenol, that is to say, lower pH, higher Eh, organic matter, moisture, volatile phenol was in favor of reducing the Bioavailability of Cd and Cd accumulation in tea.

Abstract: Polyethylene (PE) is one of the most abundant commercially produced synthetic polymers which have leaded the seriously solid pollution. A Gram positive rod form bacterium T6 has been isolated from the guts of Indian meal moth Plodia interpunctella (Hübner). According to the phenotypic, Physiological and biochemical characteristics, and 16S rRNA gene sequence, T6 is identified as Baccillus megaterium. Scanning electron microscope (SEM) reveals the polyethylene can be degraded significantly by T6 from the LDPE surface. The tensile strength of the LDPE films which is degraded by T6 strain, displays decreasing tendency as the incubation time increase. After 28 days’ incubation, the tensile strength decreases 5.8% and the maximum decrement reaches 18.4%. The difference between the tensile strength value of day 21 and day 28 are not significant (P <0.05). The results indicate T6 strain can degraded the LDPE film.

Abstract: Abstract: Pd/Ti electrode was prepared on Ti substrate electrode in hydrochloric acid containing PdCl2 using cyclic voltammetry. The electrocatalytic performance toward electrochemical reduction reactivity of 2,4-dichlorobenzoic acid (2,4-DCBA) on Cu, Ag, Ti and Pd/Ti was investigated. Compared with Cu, Ag and Ti electrodes, Pd/Ti electrode exhibited a high electrochemical activity for the reduction process of 2,4-DCBA in NaOH solution. In situ FTIR was applied to analyze the electrochemical dechlorination mechanism of 2,4-DCBA systematically. The results showed that 2,4-DCBA was electroreduced to its free radical ion after receiving an electron. Then the 2,4-DCBA free radical took off two chloride ions and produced the benzoic acid free radical. After receiving another two electrons and two protons, the final product benzoic acid was obtained.

Abstract: Abstract. Electrochemical hydrodeiodination of 2-iodobenzoic acid in NaOH solution was investigated using cyclic voltammetry. Compared with Ti and Pt electrodes, Cu electrode exhibited good electrocatalyitc activity for the electroreduction of 2-iodobenzoic acid. In situ FTIR results suggested that the mechanism of the reaction was electrochemical hydrodeiodination process. 2-Iodobenzoic acid was electroreduced to its free radical ion after receiving an electron firstly. Then the free radical ion was further deiodinated to produce benzoic acid free radical at more negative potential. After receiving another electron and proton, benzoic acid was obtained.

Abstract: The degradation kinetics of 2,4-dinitrophenol (2,4-DNP) and 2,6-dinitrophenol (2,6-DNP) were investigated in this paper. The degradation kinetics experiments were conducted in sequencing batch reactor (SBR) and the degradation model was analyzed by nonlinear regression to estimate parameters including the degradation rate K_max, half saturation constant K_S and the inhibition constant K_I in the Andrews inhibition equation. The degradation inhibition in the condition of 2,4-DNP as solo substrate is more serious than that of the situation with glucose as co-substrate and K_max decreases with the increase of inflow 2,4-DNP concentration. As for 2,6-DNP, K_max gets maximum value is 0.019 mg/(mgSS×d) at the inflow concentration is 20mg/L. K_S increases with the increasing of inflow 2,6-DNP concentration but there is no regularity for K_I.

Abstract: Soil contamination with pesticide has caused critical environmental and health defects and increasing attention has been paid for developing innovative technology for cleaning up this contamination. In this study, the effects of cationic surfactant cetyl trimethyl ammonium bromide, anionic surfactant sodium dodecylbenzenesulfonate, and non-ionic Tween 80 on the adsorption of fluazinam at the concentration of 1/2 CMC, 1 × CMC and 2 × CMC in three soils were evaluated by using batch equilibrium experiment. The K values followed the order as: S1 > S2 > S3 in absence of surfactants. The use of a nonionic surfactant considerably weaken the fluazinam retention, while that of cationic surfactant has the reverse trend. The effects of anionic surfactant on the adsorption of fluazinam in soils is related to soil physicochemical properties and anionic surfactant concentration. These results are of practical interest in developing effective surfactant remediation technology for fluazinam contaminated soils.

Abstract: An ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate( [BMIM] BF₄) / salt aqueous two-phase systems (ATPS) was presented as a simple, rapid and effective sample pretreatment technique coupled with double-beam UV-Vis spectrophotometer for analysis of gatifloxacin in water. For the purpose to choose optimal conditions, various factors were considered systematically, and the results indicated that the pH value, the salt-out ability of salt and the amount of [BMIM] BF₄ had great influence on phase separation and extraction. Under the optimal condition, gatifloxacin in different concentration were enriched and determined, the recovery was 87.3–91.5%.