Advanced Materials Research Vols. 518-523

Abstract: A series of nitrochalcones (compounds 1-10) were synthesized by reacting appropriate nitroacetophenones and suitable benzaldehydes. The synthesized products were evaluated for their cytotoxic, antibacterial (Bacillus subtilis, Escherichia coli, Pseudomonas fluorescence and Staphylococcus aureus) and antifungal (Aspergillus niger, Candida albicans and Trichophyton rubrum) activities in vitro. Among the compounds tested, (E)-3-(4-fluorophenyl)-1-(3-nitrophenyl)- prop-2-en-1-one (10) showed the favorable in vitro cytotoxic activity against human nasopharyngeal epidermoid tumor cell line KB, and (E)-3-(2-methoxyphenyl)-1-(3-nitrophenyl)prop-2-en-1-one (8) showed the strongest antimicrobial activity with MIC of 20 μg/mL against P. fluorescence.

Abstract: One of the key issues of river basin ecological compensation is the compensation standard. The opportunity cost has the character of uncertainty. The character of opportunity cost in river basin ecological compensation standard was studied on base of economics theory. The current opportunity cost accounting method didn’t consider the uncertainty of opportunity cost. The real option model of opportunity cost in river basin ecological compensation was set up based on the binomial expression real-option model. The Xin 'an river basin was applied for the model and tested the feasibility of the real option model.

Abstract: L-threonine (2S,3S) was obtained from easily available L-threonine (2S,3R) after four steps,then seven chiral ligands 9a-9g were prepared by the esterification,condensation,reductive alkylation,cyclization,then reduction with treatment with RMgX.All seven kinds of novel compounds were characterized by 1HNMR,13CNMR,IR and HRMS.Compound 9a was further characterized by X-ray diffraction.The X-ray structure analysis revealed that an intermolecular hydrogen bond is present.

Abstract: The 4-t-octylphenol (4-t-OP) biodegradation by alginate immobilized cells of Acinetobacter sp. was compared with its respective free cells in different media. The effects of different bead densities, pH values and practical applications of artificial seawater and wastewater on the biodegradation rate of 4-t-OP were investigated. Degradation kinetics of 4-t-OP by free and immobilized cells was well fitted with first order kinetic. The immobilized Acinetobacter sp. cells could enhance the efficiency of 4-t-OP degradation. The degradation rate and 4-t-OP half-life were 97.6% and 0.7 d, respectively. Increasing level of bead amount could also improve the degradation effects, when 400 beads per 100 mL were added, the degradation rate and 4-t-OP half-life were 96.5 % and 0.2 d respectively. The immobilized Acinetobacter sp. cells could degrade 4-t-OP both in artificial seawater and wastewater. The degradation rates were 87.7% and 84.3%, respectively, indicating its potential application of removing and biodegrading 4-t-OP under practical environment.

Abstract: Cadmium (Cd) accumulation and distribution in rice plants were investigated with six rice cultivars under different soil Cd levels. The results showed that Cd accumulations in different organs were in the order: root » stem > leaf > grain. The magnitudes of the differences among rice organs in Cd accumulations were larger for soil Cd treatments than for the control. The magnitudes of the variations among rice cultivars in Cd accumulations were the largest in grains, followed by roots, and the smallest in stems and leaves, and these were also larger for soil Cd treatments than for the control. Cd absorbed by rice plants were mostly accumulated in roots (about 80% for the control and more than 90% for soil Cd treatments), and only a very small portion was transferred into grains (about 2% for the control and less than 1% for soil Cd treatments). The magnitudes of the variations among rice cultivars in Cd distributions were larger for soil Cd treatments than for the control.

Abstract: Cu supported on acid-treated sepiolite catalysts (xCu/H-Sep, x = 0  20.0 wt%) or Cu-Fe mixed supported on acid-treated sepiolite catalysts (yFe-10Cu/H-Sep, y = 0  20.0 wt%) were prepared by the incipient wetness impregnation method. The xCu/H-Sep and yFe-10Cu/H-Sep catalysts were characterized by means of XRD, BET, XRF, XPS, and H2-TPR techniques, and their catalytic activities were evaluated for the SCR of NO with propylene. XPS and XRD results indicate that there was the co-presence of Cu+-Cu2+ and Fe2+-Fe3+ over the surfaces of yFe-10Cu/H-Sep catalysts, and there was a strong interaction between Cu, Fe and sepiolite. High promotional effect of iron additive on the catalytic performance of Cu/H-Sep catalyst were found in C3H6-SCR of NO reaction. The highest activity of 65% NO conversion was obtained over 15Fe-10Cu/H-Sep catalyst at 280 oC under the condition of 1000 ppm NO, 1000 ppm C3H6, and 5% O2. The high catalytic activity of 15Fe-10Cu/H-Sep catalyst for NO reduction was due to its high reducibility to activate C3H6 to selectively reduce NO in the presence of excess O2. The high dispersion of copper oxides and strong metal-support interaction over 15Fe-10Cu/H-Sep catalyst also improve its catalytic performance.

Abstract: Glycidyl trimethyl ammonium chloride (GTA) has been synthesized and used as cross-linked cationic reagent to prepare modified starch. The adsorption behavior of Cr(VI) onto the cross-linked cationic starch was studied systematically. The adsorption time and the temperature took great effects on the adsorption performance of the adsorbent. After a suitable time the adsorption could reach an equilibrium state and the adsorption capacity increased with the decrease of the temperature. The adsorption isotherm and the kinetic equation were established and they fit well with the Freundlich and Lagergren models, respectively. The used adsorbent was regenerated with acid medium and the recycling of the regenerated adsorbent has also been investigated.

Abstract: Azo dyes are extensively used in the industry, resulting in the large amount of wastewater. Redox mediators (R.M.) can accelerate the chemical reduction of azo dye by shuttling electrons from primary electron donors such as sulfide to azo dyes. Three different types of R.M. were studied on the enhancement of chemical reduction of Acid Orange 7. The electron shuttle ability of these types of R.M. with 2.5 mM of initial sulfide concentration at pH 7.5, either dissolved or undissolved type, followed in order by riboflavin, humic acid and activated carbon. The potential engineering application of these R.M. lie on the superior catalytic ability for riboflavin, wide existence in the environment for humic acid, and retaining in the bioreactors all the times for activated carbon.

Abstract: The synergy of indirect and direct electrooxidation of p-nitrophenol (PNP) at Ti/PbO2 anode was studied with linear sweeping voltammetry and galvanostatic electrolysis. The concentration of PNP and the form of redox medium were detected by high performance liquid chromatography (HPLC) and ion chromatography. The results indicated that Ti/PbO2 electrode can electrocatalyze the degradation of PNP effectively. The degradation ratio of 1.0 mmol/L PNP is 64.5% after 1 h electrolysis when the temperature is 35°C, the current density is 40 mA•cm-2. When the electrolyte containe 1.0 mmol / L Cl-, the degradation ratio of PNP is 81.0% after 1 h electrolysis under the same conditions. Cl-, ClO-, and ClO3- were detected simultaneously in the electrolyte, and their concentrations showed nonlinear oscillation with electrolysis time. These indicated that Cl- cause indirect electrooxidation of PNP, and the redox medium Cl-/Cl2 has a good reversibility.

Abstract: Methanogens play an important role in the anaerobic digestion and production of methane, and show significant influence on the performance of anaerobic wastewater treatment process. Then the methanogens in anaerobic granular sludge samples from full-scale UASB bioreactors treating avermectin or starch wastewater were detected by FISH using 16S rRNA gene-based probe and functional gene-based probes. The results showed that the hybridization of methanogens in simultaneous FISH with mcrA gene-based and 16S rRNA gene-based probes was high coincident and the coincidence degree was about 60%-80%, implying the preferable hybridization consistency between functional gene-based probe and 16S rRNA gene-based probe. The relative abundance of methanogens obtained in FISH analysis using 16S rRNA gene-based probe seemed higher than that using functional gene-based probes, indicating that functional gene could provide more specific detection of methanogens than 16S rRNA gene probably. For functional gene-based probes, the methanogen-specificity was in the following order: mcrA＜F420＜mtr. During the development process of both granular sludge samples, the maximum relative abundance of methanogens was obtained at its mature phase using all probes. The relative abundance of methanogens in the sludge sample treating avermectin wastewater was lower than that treating starch wastewater, indicating smaller methanogenic population in the sludge sample treating avermectin wastewater due to inhibitory effect of antibiotic residue on methanogens probably.