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Cyanobacterial bloom events in South Taihu Lake cause serious water quality problems and disturb aesthetic view of lake’s environment. In this study, correlations between cyanobacterial blooms and hydro-meteorological factors, including water quality, temperature and precipitation were investigated. Results demonstrated that South Taihu Lake was heavily affected by cyanobacteria and the proliferation of cyanobacteria due to variations in hydro-meteorological factors and water quality conditions. Water quality parameters, including COD, NH3-N, TN and TP improved significantly since 2008 even at an elevated cyanobacterial bloom situation. Correlation analyses have shown that the development of cyanobacterial density and chlorophyll a concentration was sensitive to a wider temperature variation. The optimum temperature for cyanobacteria was 20°C, while extremely low and high temperatures were found to suppress their growth. Moreover, unusual rainfall patterns were measured during the study period (2003–2009), which showed an adverse impact on cyanobacterial development. Findings from this study suggested that seasonal lake’s water quality monitoring; suitable treatment of cyanobacterial blooms and strict policy implementation can solve the water quality issues in highly eutrophic lakes like Taihu. [ABSTRACT FROM PUBLISHER]

Hot brine injection is one of the most effective dissociation methods of natural gas hydrate, and the movement of thermal front is a key parameter to evaluate the production performance by hot brine injection. Based on the principle of energy conservation, a mathematical model for thermal front movement of gas hydrate dissociation by hot brine injection is developed, which is derived through Laplace transform. In addition, an experimental study on the movement of thermal front is conducted with a self-designed 1D natural gas hydrate dissociation apparatus. The thermal front movement of the experiment is compared with that calculated from the mathematical model established in this paper as well as other two models proposed by Selim and Sloan (1990) and Tang et al. (2006), respectively. It turns out that what fits better with the experimental data is the energy conservation model, which includes the effect of heat used to warm the dissociated reservoir, heat absorption by hydrate dissociation and heat loss to the cap and base sediments. Therefore, this energy conservation model is an effective method to analyze the thermal front of gas hydrate dissociation by hot brine injection. [ABSTRACT FROM PUBLISHER]

In the presence of a catalytic amount cesium hydroxide, the corresponding aryltellurophosphates can be obtained by the reactions of dialkyl phosphites with diaryl ditellurides in excellent yield at room temperature, using dimethylsulfoxide as solvent. The possible reaction mechanism was discussed. The method could provide a new and expedient path for the preparation of aryltellurophosphates. [ABSTRACT FROM AUTHOR]

The catalytic dechlorination of2,4-dichlorophenol (2,4-DCP) by Ni/Fe bimetallic nanoparticles in the presence of humic acid (HA) was investigated in order to understand their applicability forin situremediation of groundwater.2,4-DCP was catalytically dechlorinated to form the final products – phenol (P) via two intermediates,o-chlorophenol (o-CP) andp-chlorophenol (p-CP). It was demonstrated that the carbon mass balances during the dechlorination were between 84% and 92%, and other carbons were adsorbed on the surface of Ni/Fe bimetallic nanoparticles. The experimental results suggest that HA competed for reaction sites on the Ni/Fe bimetallic nanoparticles with2,4-DCP, and thus reduced the efficiency and rate of the dechlorination of2,4-DCP. The catalytic degradation slowed down as the increase of HA in solution, and when HA's concentrations were 0, 10, 20 and 30 mg L−1, the maximum concentrations ofo-CP were 0.025, 0.041, 0.039 and 0.034 mM in 10, 30, 30 and 30 min, respectively. High Ni content, low initial pH value, high Ni/Fe nanoparticles’ dosage and high temperature favoured the catalytic dechlorination of2,4-DCP. The experimental results show that no other intermediates were generated besides Cl−,o-CP,p-CP and P during the catalytic dechlorination of2,4-DCP. [ABSTRACT FROM PUBLISHER]

The effects of the combination of silane functionalized hollow glass beads (silanized HGBs), acid functionalized carbon nanotubes (oxidized CNTs), and short carbon fibers (SCFs) on the tensile properties of epoxy (EP) resin were investigated. The combined utilization of silanized HGBs, oxidized CNTs and SCFs led to a pronounced synergy in the tensile properties of the SCF/HGB/CNT/EP composites. The composites exhibited greater tensile strength and Young's modulus than the neat EP, clearly. The mechanism of such synergetic effect was analyzed by tensile fracture studies using SEM. In addition, by analyzing the DSC curves, the curing temperatures of the composites were obtained. [ABSTRACT FROM PUBLISHER]

The suppressed ion chromatography (IC) and molybdenum blue methods were used to comparatively evaluate phosphorus (P) concentrations. Most of the P was more resistant to hydrolysis in ion chromatography as compared to the molybdenum blue method. However, P analysis by IC is more liable to be interfered than the molybdenum blue method because of the presence of high bivalent and trivalent metal ions. Polyvalent metal ions interfere with organic P hydrolysis or the release of P from colloids during P investigation, which leads to a difference ofortho-phosphate concentrations determined by IC and molybdenum blue methods. During the environmental samples analysis, theortho-phosphate obtained by the IC method was usually less than that obtained by the molybdenum blue method. [ABSTRACT FROM AUTHOR]

The transient state of the phase morphology of polypropylene with poly(ethylene-co-1-octene) blends during melt mixing are investigated by the pattern analysis of scanning electron microscope (SEM). The results show that morphology develops mainly at the initial stages of mixing. During the intermediate mixing stage, a dynamic equilibrium is established between breakup and coalescence of domains. The mixing time required for reaching equilibrium stage reduces as shear rate increases. The fractal analysis indicates that the development of the dispersed phase during melt mixing process evolves with dynamical self-similarity partly through the competitions of break-up and coalescence of dispersed phase. [ABSTRACT FROM AUTHOR]

Air-stable zirconocene bis(perfluoroctanesulfonate)s [Cp2Zr]OSO2C8F17)2] (1) with high Lewis acidity and high thermal stability was prepared by the reaction between Cp2ZrCl2 and AgOSO2C8F17. The as-prepared complex 1 exhibits good activity and selectivity in the cyclotrimerization of various ketones to the desired 1,3,5-triaylbenzenes. Furthermore, in the cyclic experiments, the complex 1 shows little loss of activity after 10 cycles. The results afford a general and efficient method for the cyclotrimerization of ketones using Cp2Zr(OSO2C8F17)2 as catalyst. [ABSTRACT FROM AUTHOR]

Ozonation combined with UV irradiation (UV/O3) is an advanced oxidation technique that is very promising for the destruction of organic compounds in aqueous solution. In this study, chlorophene was chosen as a model substrate to investigate the effects of pH, initial substrate concentration, ozone dose, and UV light intensity in degradation experiments. The pseudo-first-order rate constant for total organic carbon (TOC) removal was 2.4 × 10-2, 9.8 × 10-4, and 6.4 × 10-2 min-1 for O3, UV, and UV/O3 treatment, respectively. Clearly, UV-enhanced ozonation leads to a synergetic increase in the overall degradation efficiency. Comparative experiments were performed to investigate the effect of the matrix (distilled water or sewage) on chlorophene removal. The organic compounds in sewage retarded the rate of chlorophene removal by 38%, probably by competitively reacting with the oxidizing agent and screening light. The compound 2-benzoylbenzo-1,4-quinone, benzo-1,4-quinone, hydroquinone and maleic acid were identified as primary intermediates by gas chromatography-mass spectrometry. The concentrations of acetic, formic and oxalic anions were detected by ion chromatography. A possible degradation pathway is proposed on the basis of the reaction products identified. [ABSTRACT FROM AUTHOR]

Titanocene perfluorooctanesulfonate is air-stable complex. In the presence of 10 mol% of the complex, reductive cleavage of an S-S bond by zinc in commercial tetrahydrofuran at room temperature led to nucleophilic sulfur anion species, which reacted with acid anhydrides to afford thioesters in good to excellent yields. [ABSTRACT FROM AUTHOR]

In the presence of a catalytic amount of cesium hydroxide under a nitrogen atmosphere, terminal alkynes reacted with diaryl disulfides at room temperature in dimethylformamide to give almost exclusively (Z)-1,2-diarylthio-1-alkene in good yields, but under an air atmosphere, the reaction gave a mixture of alkynyl sulfide and (Z)-1,2-diarylthio-1-alkene. [ABSTRACT FROM AUTHOR]

In the presence of a catalytic amount of cesium hydroxide under an air atmosphere, the reaction of diarylditellurides (1.0 mmol) with terminal alkynes (2.2 mmol) at room temperature exclusively give alkynyl tellurides in good yields. [ABSTRACT FROM AUTHOR]

Reports on the greenhouse gas (GHG) emissions from energy consumption activities in the iron and steel industry in East China. Concern on the concentration of carbon dioxide and other GHG in the atmosphere; Consumption of solid fuel by the industry; Percentage of energy consumption and emissions; Discussion of mitigation appropriate to the energy consumption and emissions.