Advanced Materials Research Vols. 518-523

Abstract: The hydroxy derivatives of aromatic hydrocarbons which have hydroxyl getup directly attached to the ring are called phenols. Small amounts of water dissolved in phenol lower the melting point to below the room temperature. This paper summarized the bioactivities and safety issues of Terpene Phenolic, and its functions, biosynthetic mechanisms, characteristics and clearing strategies of terpene phenolic compounds.

Abstract: In this paper, inorganic polymeric ferric aluminum chloride (PFAC) and composite polymeric aluminum ferric chloride polydimethyl diallylammonium chloride (PFAC-PDADMAC) were applied for the coagulation treatment of Yellow River reservoir water. The coagulation efficiency of PFAC-PDADMAC for reservoir water treatment was investigated at different weight ratios (Ferric and Aluminum to PDADMAC, Wr=2, 4 and 8). During coagulation, the size distribution, breakage factor (Bf) and recovery factor (Rf) of flocs was investigated to systemically estimate the floc characteristics of PFAC-PDADMAC coagulation system. It was confirmed that coagulation performance of PFAC-PDADMAC was better than that of PFAC when Wr and dosage were 4 and 8 mg/L, respectively for Yellow River reservoir water coagulation. Although they were more sensitive to external interference, the flocs formed by PFAC-PDADMAC coagulation system had bigger size, faster growth rate and stronger re-growth capability than that by PFAC coagulation system. At Wr=4, the floc size and growth rate of flocs by PFAC-PDMDAAC coagulation were 409μm and 54 μm/min, respectively.

Abstract: The influence of Cadmium(Cd) on exudation of low molecular weight organic acids (LMWOAs) were investigated based on the hydroponic culture experiment. Tartaric, citric, malic, and acetic acids were chosen as representatives of LMWOAs commonly present in roots exudation. We investigated the Cadmium accumulation in Triticum aestivum L.. The results showed that under the different levels of Cd, the exudation of four organic acids by roots had the different change trend. The concentrations of four organic acids in roots exudation were in the same following sequence tartaric>citric>malic>acetic. And the content of Cd in plants increased with increasing Cd concentrations. We found that at first some LMWOAs increased at low Cd treatments, we guessed that it was a normal reaction to the Cd treatment.

Abstract: Phosphate ester and its ramifications in the pesticide are virulent and some are known to be human carcinogens. The removal of phosphate ester in the leftover of the pesticide has been a major environmental concern. The Cerium(III) complex made up of a nitrogen unsaturated heterocycle ligand and Cerium ion(III) was used in the catalytic degradation of bis(4-nitrophenyl) phosphate ester (BNPP). This catalytic system showed higher catalytic activity and better reproducibility and stability than other similar Cerium(III) systems. The rate of the BNPP catalytic degradation was about 109 -fold faster than that of its spontaneous degradation at the same conditions. The Cerium(III) complex is an very effective catalyst in the degradation of the phosphate ester.

Abstract: The transformation conditions of the protoplasts from Trichoderma viride mediated by restriction enzyme were studied in this paper. The optimum generation conditions of protoplasts were as followed: 8 mg/ml glucanex was added into the phosphate buffer (pH 6.98), the mycelial that cultured for 24 hr was hydrolyzed for 4 hr at 30°C under 40 r/min shaking speed. The protoplast yield was 4.7×107 cfu/mg. The regeneneration rate of protoplast was 14.5% on CM medium contained 0.3 mol/L KCl and 0.3 mol/L Inositol. Transformants were obtained by transfering hygromycin B resistance gene into T. viride by restriction enzyme mediated integration (REMI), The preliminary identification of the transformants indicated that the exogenous gene had been integrated into T. viride genome.

Abstract: The effects of eutrophication on the absorption kinetic parameters of nitrogen and phosphorus are investigated. The results show that the kinetic characteristics of phosphate, nitrate- nitrogen, ammonia-nitrogen and nitrite-nitrogen of Nitzschia sp. are all generally in accord with the function of Michaelis-Menten equation. The Km of them are 1.81 mg/L, 1.75 mg/L, 0.20 mg/L and 4.53 mg/L, respectively. The maximum uptake rates of nitrate-nitrogen and ammonia- nitrogen are higher than that of nitrite-nitrogen, which indicates that nitrate-nitrogen and ammonia- nitrogen can be uptaken more preferential than that of nitrite-nitrogen. In conclusion, Nitzschia sp. has a fast utilized rate of ammonia-nitrogen, nitrate-nitrogen and phosphorus. This indicates that Nitzschia sp. has a good effect on water quality and it could be applied potentially to purify waste water.

Abstract: After 4 days exposed to cadmium concentration environment, the soluble protein content, SOD activity, CAT activity, POD activity and MDA content of Hydrocharis Dubia root were investigated in this paper to study if this plant can be used to waterbody restoration with cadmium pollution. The result showed that when the cadmium concentration was lower than 5 mg.L-1, the plant didn’t encounter seriously oxidant damaged. The plant root cell increased SOD activity, CAT activity and POD activity to clean up these accumulated ROS. Hydrocharis Dubia can be used to waterbody restoration with lower than 5 mg.L-1 cadmium pollution. The plant unsuitable to be used to waterbody restoration with higher than 5 mg.L-1 cadmium pollution, the plant encountered seriously oxidant stress in this level cadmium pollution.

Abstract: Scenedesmus and Microcystis usually present in nutrients-enriched freshwater, adapt to the environmental conditions by vertical migration and lead to eutrophication and algal bloom, which results in deteriorated water quality and damaged aquatic ecosystem. The vertical migrations of Scenedesmus and Microcystis with three kinds of light sources were observed in columns. The concentration of chlorophyll a was analyzed to indicate the vertical migration of the algae. The results showed that the extinction coefficients’ rang for Scenedesmus was lower than that for Microcystis, which was due to the algal self shading resulted by the lower concentration of chlorophyll a. Under different illumination, Scenedesmus cells sank down to the bottom due to the gravity and thus were taken away by the samplings, whereas, Microcystis cells floated significantly in the columns all the time. The Stokes’ Law showed that under light sources of I2 and I3 and without light source, the sedimentation coefficients for Scenedesmus were higher than those for Microcystis, while under light source of I1, the sedimentation coefficient was lower than that for Microcystis. The different cell structures lead to different vertical migrating processes: Microcystis keeps balance between buoyancy and gravity using gas-filled structures, whereas, Scenedesmus suspend through clothing a large number of bristles with a complex structure around cells, resulting high viscous forces to help to reducing sinking rates.

Abstract: The water solubility enhancement of 2,4´-DDT and 4,4´-DDT by humic acid and extracellular organic matter released from Microcystis aeruginosa was investigated by a ingenious sampling method and increasing apparent solute solubilities. Water solubility enhancements of the two DDT isomerizes by both humic acid and extracellular organic matter at the solution pH 7-11, and their solubilities increased with the increase of pH. Absorption coefficients Ciw (2,4´-DDT and 4,4´-DDT) increased with the increase of pH for HA and EOM, but Ciw for EOM are about two times than for HA at same TOC concentrations. The results suggested that more attentions should be paid to the enhancement of organic chemicals by EOM, especially in eutrophic water body where an increasing algae population usually appears, and the enhancement of DDT solubility by EOM may increase the risk of pesticide residues to organisms.

Abstract: Enhancing nitrification from municipal wastewater by bioaugmentation was investigated in a pilot plant operated in A²/O process. Reject water was used to cultivate nitrifier in O/A process (side stream), and the exceed sludge in side stream was used to bioaugmentation. The experimental results showed that bioaugmentation was very effective for enhancing nitrification. After nitrifier bioaugmentation, the NH₄⁺-N removal rate was improved more than 30% in main stream. And AUR and NUR of the activated sludge increased from 2.61 mgNH₄⁺-N /(gMLSS•h) and 2.38 mgNO₂^--N/(gMLSS•h) to 5.32 mgNH₄⁺-N /(gMLSS•h) and 3.81 mgNO₂^--N/(gMLSS•h), which was as 2.04 times and 1.60 times as those of before bioaugmentation in main stream respectively.