By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were ...By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were studied,and the mechanism of electric field on plant physiological characteristics was analyzed to provide a theoretical basis for the pollutant removal ability strengthening of artificial wetland under electricfield.The results showed that compared with the control plants,low-intensity-voltage(1 V and 3 V) had no significant effect on the normal physiological and biochemical indexes of the plants,and the growth trend was better than the control group;with the voltage increasing,plant chlorophyll content,MDA content and SOD activity were greatly affected,indicating that plants were under strong oxidative stress,and the growth was damaged.Therefore,a suitable electric field could enhance the sewage treatment effect of constructed wetland.展开更多
CO2 removal from biogas by water washing system was investigated with various parameters, including liquid/ gas ratio, pressure, temperature, and CO2 content. The results indicate that CO2 removal ratio could reach 34...CO2 removal from biogas by water washing system was investigated with various parameters, including liquid/ gas ratio, pressure, temperature, and CO2 content. The results indicate that CO2 removal ratio could reach 34.6%- 94.2% as liquid/gas ratio increased from 0.14 to 0.50. Increasing pressure (from 0.8 to 1.2 MPa) could improve gas purification with a constant inflow rate of gas. Temperature played a key role in the process and lower temper- ature in absorption tower was beneficial for reducing CO2 content. CO2 removal ratio could reach 24.4%-83.2% when CO2 content in the simulated gas was 25%-45%. The lowest CO2 content after absorption was 2.6% at 1.2 MPa with 400 L·h-1 gas flow and 200 L·h-1 water flow, which meets the requirement of CO2 content in natural Ras for vehicle fuel.展开更多
A three phase fluidized bed reactor was used to investigate the combined effect of adsorption and oxidation for phenolic wastewater treatment.Aqueous solutions containing 10 mg·L 1of phenol and ozone were continu...A three phase fluidized bed reactor was used to investigate the combined effect of adsorption and oxidation for phenolic wastewater treatment.Aqueous solutions containing 10 mg·L 1of phenol and ozone were continuously fed co-currently as upward flow into the reactor at constant flow rate of 2 and 1 L·min 1,respectively.The phenolic treatment results in seven cases were compared:(a)O3 only,(b)fresh granular activated carbon(GAC),(c) 1st reused GAC,(d)2nd reused GAC,(e)fresh GAC enhanced with O3,(f)1st reused GAC enhanced with O3,and (g)2nd reused GAC enhanced with O3.The phenolic wastewater was re-circulated through the reactor and its concentration was measured with respect to time.The experimental results revealed that the phenolic degradation using GAC enhanced with O3 provided the best result.The effect of adsorption by activated carbon was stronger than the effect of oxidation by ozone.Fresh GAC could adsorb phenol better than reused GAC.All cases of adsorption on GAC followed the Langmuir isotherm and displayed pseudo second order adsorption kinetics.Finally,a differential equation for the fluidized bed reactor model was used to describe the phenol concentration with respect to time for GAC enhanced with O3.The calculated results agree reasonably well with the experimental results.展开更多
This study investigated the removal and transformation of organic matter through laboratory-scale soil-aquifer treatment (SAT) soil columns over a 110-day period. Reductions in total organic carbon (TOC), dissolved or...This study investigated the removal and transformation of organic matter through laboratory-scale soil-aquifer treatment (SAT) soil columns over a 110-day period. Reductions in total organic carbon (TOC), dissolved organic carbon (DOC), biodegradable dissolved organic carbon (BDOC), nonbiodegradable dissolved organic carbon (NBDOC) and absorbance of ul-traviolet light at 254 nm (UV-254) averaged 71.46%, 68.05%, 99.31%, 33.27% and 38.96% across the soil columns, respectively. DOC/TOC ratios increased slightly with depth while BDOC/DOC ratios showed a converse trend. DOC exiting the soil-column system contained only a very small biodegradable fraction. SAT decreased the concentration of DOC present in feed water but increased its aromaticity, as indicated by specific ultraviolet light absorbance (SUVA), which increased by 50%~115% across the soil columns, indicating preferential removal of non-aromatic DOC during SAT. Overall, laboratory-scale SAT reduced triha-lomethane formation potential (THMFP), although specific THMFP increased. THMFP reduction was dominated by removal in chloroform. All samples exhibited a common general relationship with respect to weight: chloroform>dichlorobromomethane >dibromochloromethane>bromoform.展开更多
High salinity industrial wastewater is difficult to treat using biological treatment system because of the high concentrations of salt.The potential of a sequencing batch biofilm reactor(SBBR)process in treating synth...High salinity industrial wastewater is difficult to treat using biological treatment system because of the high concentrations of salt.The potential of a sequencing batch biofilm reactor(SBBR)process in treating synthetic high salinity wastewater was evaluated at laboratory scale during a 110-day operation.The reactor was operated in a 12 h cycle,and each cycle consisted of 0.25 h influent addition,8 h aeration,3 h anoxic reaction,0.5 h sedimentation and 0.25 h effluent withdrawal.Gradual increase in salinity gradient was applied during the acclimatization period.The acclimated SBBR system was demonstrated to be an effective process to remove organic compounds and ammonia nitrogen under high salinity conditions with chemical oxygen demand(COD)and ammonia nitrogen(NH3-N)removal efficiencies of 88% and 80%,respectively.The microscopic examination indicated that rather than rotifers or vorticella,the zoogloea,filamentous fungus mingled with a small quantity of swimming infusorians were dominant bacteria in SBBR system.The removal efficiencies close to 80% in COD and 75% in NH3-N were achieved at an organic loading rate(OLR)of 0.96 kg COD/(m3·d),pH of 7.0,salinity of 14 g/L and NH3-N of 30 mg/L.展开更多
In this paper, fouling mechanisms of mullite ceramic membranes for treatment of oily wastewaters in hybrid coagulation-microfiltration (MF) process presented. Hermia's models for cross flow filtration were used to ...In this paper, fouling mechanisms of mullite ceramic membranes for treatment of oily wastewaters in hybrid coagulation-microfiltration (MF) process presented. Hermia's models for cross flow filtration were used to investigate the fouling mechanisms of membranes with various coagulating chemicals concentrations. Four coagu lating chemicals (FeC12.4H20, FeSO4.7H20, A1C13-6H20 and A12(SO4)3.18H20) plus Ca(OH)2 of the same concen- tration were evaluated in the coagulation-MF hybrid process with different concentrations (0, 50 mg.L-1, 100 mg.L-1 and 200 mg.L-1). To determine whether the data agree with models under consideration, the coefficients of determination (R2) of all models were compared with one another. In addition, average prediction errors of models were calculated. The results showed that cake filtration model can be applied for prediction of permeation flux decline for MF and coagulation-(MF) hybrid process with the best average error equal to 0.09%. Results indicated that pore blocking behavior changes as time of filtration increases, and one model cannot predict pore blocking behavior in all filtration time with very good precision.展开更多
In this study, the O3/BAC/TiO2 catalytic method was used to treat the phenolic wastewater. During the experiments the effects of initial phenol concentration, ozone concentration, pH value, catalyst and other conditio...In this study, the O3/BAC/TiO2 catalytic method was used to treat the phenolic wastewater. During the experiments the effects of initial phenol concentration, ozone concentration, pH value, catalyst and other conditions on the phenol removal rate were investigated. The test results showed that when the phenol concentration was 0.1 g/L, the ozone-containing air flow rate was 0.05 m3/b, the ozone concentration was 3.58 mg/L, the pH value was 7.5, and the treating time was 30 minutes, the phenol removal rate reached 99%, with the COD removal rate equating to 55%. The property of treated wastewater could comply with the first-grade effluent specified in "Comprehensive Wastewater Discharge Standard" (GB8978--1996).展开更多
Soil respiration from decomposing aboveground litter is a major component of the terrestrial carbon cycle. However, variations in the contribution of aboveground litter to the total soil respiration for stands of vary...Soil respiration from decomposing aboveground litter is a major component of the terrestrial carbon cycle. However, variations in the contribution of aboveground litter to the total soil respiration for stands of varying ages are poorly understood. To assess soil respiration induced by aboveground litter, treatments of litter and no litter were applied to 5-, l0-, and 20-year-old stands of Populus davidiana Dode in the sandstorm source area of Beijing-Tianjin, equations were applied to China. Optimal nonlinear model the combined effects of soil temperature and soil water content on soil respiration. Results showed that the monthly average contribution of aboveground litter to total soil respiration were 18.46% ± 4.63%, 16.64% ± 9.31%, and 22.37% ± 8.17% for 5-, 10-, and ao-year-old stands, respectively. The relatively high contribution in 5- and 20-year-old stands could be attributed to easily decomposition products and high accumulated litter, resoectivelv. Also. it fluctuated monthly for all stand ages due to substrate availability caused by phenology and environmental factors. Litter removal significantly decreased soil respiration and soil water content for all stand ages (P 〈 0.05) but not soil temperature (P 〉 0.05). Variations of soil respiration could be explained by soil temperature at 5-cm depth using an exponential equation and by soil water content at lo-cm depth using a quadratic equation, whereas soil respiration was better modeled using the combined parameters of soil temperature and soil water content than with either soil temperature or soil water content alone. Temperature sensitivity (Q10) increased with stand age in both the litter and the no litter treatments. Considering the effects of aboveground litter, this study provides insights for predicting future soil carbon fluxes and for accurately assessing soil carbon budgets.展开更多
Laccase was immobilized on the ceramic-chitosan composite support by using glutaraldehyde as the cross-linking reagent. The immobilization conditions and characterization of the immobilized enzyme were investigated. T...Laccase was immobilized on the ceramic-chitosan composite support by using glutaraldehyde as the cross-linking reagent. The immobilization conditions and characterization of the immobilized enzyme were investigated. The immobilization of laccase was successfully realized when 3.0 mL of 1.25 mg/mL of laccase at a pH value of 4.0 reacted with 0.15 g of ceramic-chitosan composite support(CCCS) at 4 ℃ for 24 h. The immobilized enzyme exhibited a maximum activity at pH 3.0. The optimal temperatures for immobilized enzyme were 25 ℃ and 50 ℃. The K_m value of immobilized laccase for ABTS was 66.64 μmol/L at a pH value of 3.0 at 25 ℃. Compared with free laccase, the thermal, operating and storage stability of immobilized laccase was improved after the immobilization.展开更多
Theaim of the present work wasto analyze moisture flow and moisture content data for high-temperature drying by usingan advanced image- processing algorithm.Since wood starts to shrink below the fibre saturation point...Theaim of the present work wasto analyze moisture flow and moisture content data for high-temperature drying by usingan advanced image- processing algorithm.Since wood starts to shrink below the fibre saturation point during drying, the size and shape of wood will change. The dry wood image was thoroughly transformed to the shape of the wet wood image prior to calculating the dry weight moisture content. The use of the image- processing algorithm for the dry weight moisture content on density data from the CT-scanning during drying in a controlled high-temperature environment showed that this method is a powerful tool for analyzing the moisture flow inside the wood piece. Furthermore, the new CT-scanner together with the climate chamber gave unique results, as it has not been possible to study high-temperature drying with this method before.展开更多
Mierocystis aeruginosa FACHB 905 was used as a model organism to study the ellects oI small water clusters (SWCs) on the growth and microcystin (MC) production of toxic cyanobacteria. The results showed that SWCs ...Mierocystis aeruginosa FACHB 905 was used as a model organism to study the ellects oI small water clusters (SWCs) on the growth and microcystin (MC) production of toxic cyanobacteria. The results showed that SWCs were able to stimulate the growth of Microcystis aeruginosa, which resulted in increased cell numbers and higher specific growth rates after a 30-d treatment. The cell morphology indicated that Microcystis aeruginosa was in a better state of growth, and it was more prone to divide in SWCs than in normal water clusters. The SWCs treatment up-regulated MC synthesis and exudation in 10 d in Microcystis aeruginosa, and the intra-cellular MC content de- creased after the 20th day subsequently. Moreover, the cellular photosynthetic pigment contents were temporarily stimulated by SWCs. A possible reason is that SWCs stimulated the growth by promoting photosynthesis, whereas the increased MC production was relevant to pigment contents.展开更多
The recovery of Au by activated carbon fibers (ACFs) was carried out in a 40mm diameter, 1200mm height fluidized bed. The rates of reaction of the functional fibers with Au3+ in the pure aurum solution and in the auru...The recovery of Au by activated carbon fibers (ACFs) was carried out in a 40mm diameter, 1200mm height fluidized bed. The rates of reaction of the functional fibers with Au3+ in the pure aurum solution and in the aurum-containing wastewater were measured respectively at the different solution flow rates, and compared with the results under the static solution conditions. Experimental results indicated that the reaction rates in fluidization are notably higher than those in the static state and increase with the increase of solution flow rate. It demonstrates that the thickness of the concentration boundary layer is decreased and a uniform temperature field is established in the bed due to increasing of the turbulent extent with the relative fiber/solution velocity.展开更多
The thermal stability of five commercial ion-exchange resin catalysts was studied by means of thermal gravimetric analysis (TGA) at elevated temperatures of up to 600℃ and isothermal temperatures in the range of 15...The thermal stability of five commercial ion-exchange resin catalysts was studied by means of thermal gravimetric analysis (TGA) at elevated temperatures of up to 600℃ and isothermal temperatures in the range of 150℃ and 200 ℃. Resin samples with different initial water contents were also investigated. The study indicated that TGA, as a complementary evaluating method for the plug flow reactor system approach, could be used as a fast analyzing means for study on the thermal stability of ion-exchange resin catalysts. The stoichiometric calculation of the isothermally treated resin catalysts based on the FTIR analysis and acid capacity confirmed that the weight loss of the resins at 150℃ and 200℃ was caused by the desulfonation process and that desulfonation occurred mainly at the para-position of the benzene ring in the resins. H+ ions and moisture played an important role in the desulfonation process.展开更多
基金Supported by Natural Science Foundation of Shanghai(10ZR1400300 )Central University Special Foundation of Basic Research and Operating expenses+1 种基金Creative Group Foundation of the National Natural Science Foundation of China (50721006)Key Discipline construction Project of Shanghai (B604)~~
文摘By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were studied,and the mechanism of electric field on plant physiological characteristics was analyzed to provide a theoretical basis for the pollutant removal ability strengthening of artificial wetland under electricfield.The results showed that compared with the control plants,low-intensity-voltage(1 V and 3 V) had no significant effect on the normal physiological and biochemical indexes of the plants,and the growth trend was better than the control group;with the voltage increasing,plant chlorophyll content,MDA content and SOD activity were greatly affected,indicating that plants were under strong oxidative stress,and the growth was damaged.Therefore,a suitable electric field could enhance the sewage treatment effect of constructed wetland.
基金Supported by the National Technology Research and Development Program of China(2008AA062402)the China-US International Cooperation Project(2011DFA90800)the Ministry of Science and Technology,China
文摘CO2 removal from biogas by water washing system was investigated with various parameters, including liquid/ gas ratio, pressure, temperature, and CO2 content. The results indicate that CO2 removal ratio could reach 34.6%- 94.2% as liquid/gas ratio increased from 0.14 to 0.50. Increasing pressure (from 0.8 to 1.2 MPa) could improve gas purification with a constant inflow rate of gas. Temperature played a key role in the process and lower temper- ature in absorption tower was beneficial for reducing CO2 content. CO2 removal ratio could reach 24.4%-83.2% when CO2 content in the simulated gas was 25%-45%. The lowest CO2 content after absorption was 2.6% at 1.2 MPa with 400 L·h-1 gas flow and 200 L·h-1 water flow, which meets the requirement of CO2 content in natural Ras for vehicle fuel.
基金Supported by the National Nanotechnology Center(NANOTEC)(601003)the National Science and Technology Development Agency(NSTDA)
文摘A three phase fluidized bed reactor was used to investigate the combined effect of adsorption and oxidation for phenolic wastewater treatment.Aqueous solutions containing 10 mg·L 1of phenol and ozone were continuously fed co-currently as upward flow into the reactor at constant flow rate of 2 and 1 L·min 1,respectively.The phenolic treatment results in seven cases were compared:(a)O3 only,(b)fresh granular activated carbon(GAC),(c) 1st reused GAC,(d)2nd reused GAC,(e)fresh GAC enhanced with O3,(f)1st reused GAC enhanced with O3,and (g)2nd reused GAC enhanced with O3.The phenolic wastewater was re-circulated through the reactor and its concentration was measured with respect to time.The experimental results revealed that the phenolic degradation using GAC enhanced with O3 provided the best result.The effect of adsorption by activated carbon was stronger than the effect of oxidation by ozone.Fresh GAC could adsorb phenol better than reused GAC.All cases of adsorption on GAC followed the Langmuir isotherm and displayed pseudo second order adsorption kinetics.Finally,a differential equation for the fluidized bed reactor model was used to describe the phenol concentration with respect to time for GAC enhanced with O3.The calculated results agree reasonably well with the experimental results.
基金Project (No. 2004CB418505) supported by the National Basic Research Program (973) of China
文摘This study investigated the removal and transformation of organic matter through laboratory-scale soil-aquifer treatment (SAT) soil columns over a 110-day period. Reductions in total organic carbon (TOC), dissolved organic carbon (DOC), biodegradable dissolved organic carbon (BDOC), nonbiodegradable dissolved organic carbon (NBDOC) and absorbance of ul-traviolet light at 254 nm (UV-254) averaged 71.46%, 68.05%, 99.31%, 33.27% and 38.96% across the soil columns, respectively. DOC/TOC ratios increased slightly with depth while BDOC/DOC ratios showed a converse trend. DOC exiting the soil-column system contained only a very small biodegradable fraction. SAT decreased the concentration of DOC present in feed water but increased its aromaticity, as indicated by specific ultraviolet light absorbance (SUVA), which increased by 50%~115% across the soil columns, indicating preferential removal of non-aromatic DOC during SAT. Overall, laboratory-scale SAT reduced triha-lomethane formation potential (THMFP), although specific THMFP increased. THMFP reduction was dominated by removal in chloroform. All samples exhibited a common general relationship with respect to weight: chloroform>dichlorobromomethane >dibromochloromethane>bromoform.
基金Projects(ZR2013BL010,ZR2012DL05)supported by the Natural Science Foundation of Shandong Province,ChinaProject(4041412016)supported by the Research Excellence Award of Shandong University of Technology,ChinaProjects(2013GG03116,2011GG02115)supported by the Science and Technology Development Planning Project of Zibo,China
文摘High salinity industrial wastewater is difficult to treat using biological treatment system because of the high concentrations of salt.The potential of a sequencing batch biofilm reactor(SBBR)process in treating synthetic high salinity wastewater was evaluated at laboratory scale during a 110-day operation.The reactor was operated in a 12 h cycle,and each cycle consisted of 0.25 h influent addition,8 h aeration,3 h anoxic reaction,0.5 h sedimentation and 0.25 h effluent withdrawal.Gradual increase in salinity gradient was applied during the acclimatization period.The acclimated SBBR system was demonstrated to be an effective process to remove organic compounds and ammonia nitrogen under high salinity conditions with chemical oxygen demand(COD)and ammonia nitrogen(NH3-N)removal efficiencies of 88% and 80%,respectively.The microscopic examination indicated that rather than rotifers or vorticella,the zoogloea,filamentous fungus mingled with a small quantity of swimming infusorians were dominant bacteria in SBBR system.The removal efficiencies close to 80% in COD and 75% in NH3-N were achieved at an organic loading rate(OLR)of 0.96 kg COD/(m3·d),pH of 7.0,salinity of 14 g/L and NH3-N of 30 mg/L.
文摘In this paper, fouling mechanisms of mullite ceramic membranes for treatment of oily wastewaters in hybrid coagulation-microfiltration (MF) process presented. Hermia's models for cross flow filtration were used to investigate the fouling mechanisms of membranes with various coagulating chemicals concentrations. Four coagu lating chemicals (FeC12.4H20, FeSO4.7H20, A1C13-6H20 and A12(SO4)3.18H20) plus Ca(OH)2 of the same concen- tration were evaluated in the coagulation-MF hybrid process with different concentrations (0, 50 mg.L-1, 100 mg.L-1 and 200 mg.L-1). To determine whether the data agree with models under consideration, the coefficients of determination (R2) of all models were compared with one another. In addition, average prediction errors of models were calculated. The results showed that cake filtration model can be applied for prediction of permeation flux decline for MF and coagulation-(MF) hybrid process with the best average error equal to 0.09%. Results indicated that pore blocking behavior changes as time of filtration increases, and one model cannot predict pore blocking behavior in all filtration time with very good precision.
文摘In this study, the O3/BAC/TiO2 catalytic method was used to treat the phenolic wastewater. During the experiments the effects of initial phenol concentration, ozone concentration, pH value, catalyst and other conditions on the phenol removal rate were investigated. The test results showed that when the phenol concentration was 0.1 g/L, the ozone-containing air flow rate was 0.05 m3/b, the ozone concentration was 3.58 mg/L, the pH value was 7.5, and the treating time was 30 minutes, the phenol removal rate reached 99%, with the COD removal rate equating to 55%. The property of treated wastewater could comply with the first-grade effluent specified in "Comprehensive Wastewater Discharge Standard" (GB8978--1996).
基金funded by the National Natural Science Foundation of China (Grant No.31170414)the 100 Talents Program of Chinese Academy of Sciences,and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No.XDA05060600)
文摘Soil respiration from decomposing aboveground litter is a major component of the terrestrial carbon cycle. However, variations in the contribution of aboveground litter to the total soil respiration for stands of varying ages are poorly understood. To assess soil respiration induced by aboveground litter, treatments of litter and no litter were applied to 5-, l0-, and 20-year-old stands of Populus davidiana Dode in the sandstorm source area of Beijing-Tianjin, equations were applied to China. Optimal nonlinear model the combined effects of soil temperature and soil water content on soil respiration. Results showed that the monthly average contribution of aboveground litter to total soil respiration were 18.46% ± 4.63%, 16.64% ± 9.31%, and 22.37% ± 8.17% for 5-, 10-, and ao-year-old stands, respectively. The relatively high contribution in 5- and 20-year-old stands could be attributed to easily decomposition products and high accumulated litter, resoectivelv. Also. it fluctuated monthly for all stand ages due to substrate availability caused by phenology and environmental factors. Litter removal significantly decreased soil respiration and soil water content for all stand ages (P 〈 0.05) but not soil temperature (P 〉 0.05). Variations of soil respiration could be explained by soil temperature at 5-cm depth using an exponential equation and by soil water content at lo-cm depth using a quadratic equation, whereas soil respiration was better modeled using the combined parameters of soil temperature and soil water content than with either soil temperature or soil water content alone. Temperature sensitivity (Q10) increased with stand age in both the litter and the no litter treatments. Considering the effects of aboveground litter, this study provides insights for predicting future soil carbon fluxes and for accurately assessing soil carbon budgets.
文摘Laccase was immobilized on the ceramic-chitosan composite support by using glutaraldehyde as the cross-linking reagent. The immobilization conditions and characterization of the immobilized enzyme were investigated. The immobilization of laccase was successfully realized when 3.0 mL of 1.25 mg/mL of laccase at a pH value of 4.0 reacted with 0.15 g of ceramic-chitosan composite support(CCCS) at 4 ℃ for 24 h. The immobilized enzyme exhibited a maximum activity at pH 3.0. The optimal temperatures for immobilized enzyme were 25 ℃ and 50 ℃. The K_m value of immobilized laccase for ABTS was 66.64 μmol/L at a pH value of 3.0 at 25 ℃. Compared with free laccase, the thermal, operating and storage stability of immobilized laccase was improved after the immobilization.
文摘Theaim of the present work wasto analyze moisture flow and moisture content data for high-temperature drying by usingan advanced image- processing algorithm.Since wood starts to shrink below the fibre saturation point during drying, the size and shape of wood will change. The dry wood image was thoroughly transformed to the shape of the wet wood image prior to calculating the dry weight moisture content. The use of the image- processing algorithm for the dry weight moisture content on density data from the CT-scanning during drying in a controlled high-temperature environment showed that this method is a powerful tool for analyzing the moisture flow inside the wood piece. Furthermore, the new CT-scanner together with the climate chamber gave unique results, as it has not been possible to study high-temperature drying with this method before.
基金Supported by National High Technology Research and Development Program of China ("863" Program,No.2012AA063504)National Natural Science Foundation of China(No.20676094)Scientific Project of Ocean Development of Tianjin Oceanic Administration(No.KJXH2011-10)
文摘Mierocystis aeruginosa FACHB 905 was used as a model organism to study the ellects oI small water clusters (SWCs) on the growth and microcystin (MC) production of toxic cyanobacteria. The results showed that SWCs were able to stimulate the growth of Microcystis aeruginosa, which resulted in increased cell numbers and higher specific growth rates after a 30-d treatment. The cell morphology indicated that Microcystis aeruginosa was in a better state of growth, and it was more prone to divide in SWCs than in normal water clusters. The SWCs treatment up-regulated MC synthesis and exudation in 10 d in Microcystis aeruginosa, and the intra-cellular MC content de- creased after the 20th day subsequently. Moreover, the cellular photosynthetic pigment contents were temporarily stimulated by SWCs. A possible reason is that SWCs stimulated the growth by promoting photosynthesis, whereas the increased MC production was relevant to pigment contents.
基金Natural Science Foundation of Guangdong Province (№: 970513) and The High Technology Research and Development Program of China (№: 863-715-004-0240)
文摘The recovery of Au by activated carbon fibers (ACFs) was carried out in a 40mm diameter, 1200mm height fluidized bed. The rates of reaction of the functional fibers with Au3+ in the pure aurum solution and in the aurum-containing wastewater were measured respectively at the different solution flow rates, and compared with the results under the static solution conditions. Experimental results indicated that the reaction rates in fluidization are notably higher than those in the static state and increase with the increase of solution flow rate. It demonstrates that the thickness of the concentration boundary layer is decreased and a uniform temperature field is established in the bed due to increasing of the turbulent extent with the relative fiber/solution velocity.
基金supported financially by the Purolite Company and Chinese National Natural Science Foundation(20674069)
文摘The thermal stability of five commercial ion-exchange resin catalysts was studied by means of thermal gravimetric analysis (TGA) at elevated temperatures of up to 600℃ and isothermal temperatures in the range of 150℃ and 200 ℃. Resin samples with different initial water contents were also investigated. The study indicated that TGA, as a complementary evaluating method for the plug flow reactor system approach, could be used as a fast analyzing means for study on the thermal stability of ion-exchange resin catalysts. The stoichiometric calculation of the isothermally treated resin catalysts based on the FTIR analysis and acid capacity confirmed that the weight loss of the resins at 150℃ and 200℃ was caused by the desulfonation process and that desulfonation occurred mainly at the para-position of the benzene ring in the resins. H+ ions and moisture played an important role in the desulfonation process.