Density （ρ） and viscosity （η） measurements were carried out for 4-aminobutyric acid in 0.0041,0.0125 and 0.0207 mol·L-1 aqueous salbutamol sulphate at T=308.15,313.15 and 318.15K.The measured values of dens...Density （ρ） and viscosity （η） measurements were carried out for 4-aminobutyric acid in 0.0041,0.0125 and 0.0207 mol·L-1 aqueous salbutamol sulphate at T=308.15,313.15 and 318.15K.The measured values of density and viscosity were used to estimate some important parameters such as apparent molar volume Vφ,limiting apparent molar volume Vφ0,transfer volume △Vφ0,hydration number Hn,second derivative of infinite dilution of partial molar volume with temperature 2Vφ0/T2,viscosity B-coefficients,variation of B with temperature dB/dT,free energy of activation per mole of solvent △μ10＊ and solute △μ20＊,activation entropy △S20＊ and activation enthalpy △H20＊ of the amino acids.These parameters have been interpreted in terms of solute-solute and solute-solvent interactions and structure making/breaking ability of solutes in the given solution.展开更多
Excess molar volumes (V^E_m) of binary mixtures of2-methyl-3-buten-3-ol [CH_3C(OH)(CH_3)CHCG_2] with four 1-alcohols:methanol, ethanol, 1-propanol and l-butanol at 298.15 K andatmospheric pressure are derived from den...Excess molar volumes (V^E_m) of binary mixtures of2-methyl-3-buten-3-ol [CH_3C(OH)(CH_3)CHCG_2] with four 1-alcohols:methanol, ethanol, 1-propanol and l-butanol at 298.15 K andatmospheric pressure are derived from density measurements with avibrating-tube densimeter. All the excess volumes are negative in thesystems over the entire composition range. The results are correlatedwith the Redlich-Kister equation. The effects of chain length ofl-alcohols on V^E_m are discussed. The apparent molar volumes of2-methyl-3-ol and l-alcohols are calculated respectively.展开更多
The present paper studies the sedimentary characteristics and mechanism of the shell ridges on the southwestern coast of Bohai Bay, which are the largest and have the highest shell (or shell fragment) content in the w...The present paper studies the sedimentary characteristics and mechanism of the shell ridges on the southwestern coast of Bohai Bay, which are the largest and have the highest shell (or shell fragment) content in the world. These shell ridges are composed of two sedimentary subfacies: the ridge subfacies and the ridge infill subfacies with different inner textures and sedimentary structures. The ridge subfacies primarily consists of fresh shells and/or shell fragments with parallel beddings and high-angle oblique beddings. The ridge infill subfacies consists of finer shell fragments and silty sand with parallel beddings oblique to land. The evolution of the shell ridge is controlled by the accumulation of substantial shell material,the relative slow erosion of shoreline, storm waves, winds and the shift of river routes. Wind tunnel tests indicate that the critical movement velocity of shell is lower than that of quartz sand of the same grain size. Deltaic progradation alternates with shell ridge growth. While the Yellow River empties into the sea through this area, accompanied by deltaic progradating, the shell material is scarce, which is unfavorable to the growth of the shell ridge. Conversely, erosion occurs along an abandoned delta coast where a shell ridge may develop, e.g. the shell ridge on the southwest of Bohai Bay.展开更多
The extraction fraction E and overall volumetric mass transfer coefficient kka of TBP extracting butyric acid pro- cess in confined impinging jet reactors （CIJR） with two jets were investigated. The main variables t...The extraction fraction E and overall volumetric mass transfer coefficient kka of TBP extracting butyric acid pro- cess in confined impinging jet reactors （CIJR） with two jets were investigated. The main variables tested were the concentration of tri-butyl-phosphate （TBP） and butyric acid, the impinging velocity V, the impinging velocityratio of two phases Vorg/Vaq, the nozzle inner diameter di and the distance L between the jet axes and the top wall of the impinging chamber. The results showed that E and kLa increase with an increase of the impinging velocity V, the concentration ofTBP Corg, and the impinging velocity ratio Vor/Vaq. However, E and kta decrease with an increase of the inner diameter d1 from 1 to 2 mm, the concentration of butyric acid Caq from 0.5% （v/v） to 2% （v/v）. The factor L ranging from 3 to 11 mm has a negligible effect on E and kLa. A correlation on these variables and kLa was proposed based on the experimental data. These results indicated good mass transfer oerformance of CIJR in the extraction operation.展开更多
The Jacobian elliptic function expansion method for nonlinear differential-different equations and its algorithm are presented by using some relations among ten Jacobian elliptic functions and successfully construct m...The Jacobian elliptic function expansion method for nonlinear differential-different equations and its algorithm are presented by using some relations among ten Jacobian elliptic functions and successfully construct more new exact doubly-periodic solutions of the integrable discrete nonlinear Schrodinger equation. When the modulous m → 1or 0, doubly-periodic solutions degenerate to solitonic solutions including bright soliton, dark soliton, new solitons as well as trigonometric function solutions.展开更多
The production of environmental friendly emulsion paint is of great significance. Vacuum steam stripping of methyl isobutyl ketone （MIBK） and methyl ethyl ketone （MEK） from cathodic electrophoretic emulsion was st...The production of environmental friendly emulsion paint is of great significance. Vacuum steam stripping of methyl isobutyl ketone （MIBK） and methyl ethyl ketone （MEK） from cathodic electrophoretic emulsion was studied. The effects of mass ratio of vapor to feed （V/F）, vacuum degree and feed temperature on removal rate of MIBK and MEK, emulsion size and solid volume fraction of the emulsion were investigated, and the removal of MIBK and MEK from cathodic electrophoretic emulsion by vacuum desorption was also studied. The results show that removal rates of both MIBK and MEK increase with the increase of V/F, vacuum degree and feed temperature. Removal rates of MIBK and MEK are 98.3% and 93.6%, respectively, at the operating condition V/F of 0.7, feed temperature of 27℃ and vacuum degree of 90 kPa. The emulsion size of cathodic electrophoretic emulsion increases slightly with feed temperature when temperature is below 42 ℃, and increases rapidly with feed temperature when temperature is above 42℃. Solid volume fraction increases by 10% as vacuum degree increases from 0 to 90 kPa at V/F of 0.7 and feed temperature of 27 ℃. Compared with vacuum desorption, vacuum steam stripping can get a higher removal rate of MIBK and MEK under the same feed flow, vacuum degree and feed temperature.展开更多
The infinite diluted activity coefficients of solvents in polyisopropyl methylacrylate was measured using inverse gas chromatography. The solvents used were benzene, toluene, ethyl benzene, methyl acetate, ethyl aceta...The infinite diluted activity coefficients of solvents in polyisopropyl methylacrylate was measured using inverse gas chromatography. The solvents used were benzene, toluene, ethyl benzene, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methanol, ethanol isopropyl alcohol, butyl alcohol, 1,2-dichloroethane, and chloroform. It was observed that the infinite diluted activity coefficient of alcohols are well above those of the other solvents investigated.展开更多
EPD （electrophoretic deposition） of barium titanate from organic medium ethanol-PVB （polyvinyl butyral） was performed on Ni, Ti, steel substrate. Stable BaTiO3 suspensions with concentration of 2 wt.% have been pr...EPD （electrophoretic deposition） of barium titanate from organic medium ethanol-PVB （polyvinyl butyral） was performed on Ni, Ti, steel substrate. Stable BaTiO3 suspensions with concentration of 2 wt.% have been prepared for the deposition. A uniform and dense layer was obtained for films deposited from ethanol with PVB of 0.1%. The surface topology of deposited films can be controlled via the applied voltage. This method allows to obtain crack-free and smooth layers BaTiO3 from organic medium with thickness of 4-20 μm.展开更多
Di-n-butyl phthalate (DBP),one of phthalate acid esters (PAEs),was investigated to determine its biodegradation rate using Xiangjiang River sediment and find potential DBP degraders in the enrichment culture of the se...Di-n-butyl phthalate (DBP),one of phthalate acid esters (PAEs),was investigated to determine its biodegradation rate using Xiangjiang River sediment and find potential DBP degraders in the enrichment culture of the sediment. The sediment sample was incubated with an initial concentration of DBP of 100 mg/L for 5 d. The biodegradation rate of DBP was detected using HPLC and the degraded products were analyzed by GC/MS. Subsequently,the microbial diversity of the enrichment culture was analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results reveal that almost 100% of DBP is degraded after merely 3 d,generating two main degraded products:mono-butyl phthalate (MBP) and 9-octadecenoic acid. After a six-month enrichment period under the pressure of DBP,the dominant family in the final enrichment culture is clustered with the Comamonas sp.,the remaining are affiliated with Sphingomonas sp.,Hydrogenophaga sp.,Rhizobium sp.,and Acidovorax sp. The results show the potential of these bacteria to be used in the bioremediation of DBP in the environment.展开更多
Phthalate esters （PAEs）, which can disturb human endocrine system, have been widely detected in vegetable greenhouse agriculture in China. To investigate the effects of environmental factors on PAEs in soils, pollut...Phthalate esters （PAEs）, which can disturb human endocrine system, have been widely detected in vegetable greenhouse agriculture in China. To investigate the effects of environmental factors on PAEs in soils, pollution sources were identified, and the cumulative risks of PAEs to humans through vegetables in the diet were evaluated in this study. Ninety-eight vegetable samples were collected from 10 markets along with 128 vegetable and 111 soil samples from agricultural greenhouses and open field. All soil and vegetable samples were contaminated with PAEs, and the total concentrations of the 5 PAEs, including dimethyl phthalate （DMP）, diethyl phthalate （DEP）, di-iso-butyl phthalate （DiBP）, di-n-butyl phthalate （DnBP）, and di-2-ethylhexyl phthalate （DEHP）, were in the ranges of 0.26-2.53 mg kg-1 for soils and 0.95-8.09 mg kg-1 for vegetables. Three components extracted from principle component analysis could explain 51.2%, 19.8%, and 15.3% of the total variance of the 5 PAEs in soils, which may represent three major sources of PAEs, i.e., wastewater irrigation, application of fertilizers and pesticides, and plastic film. Long-term greenhouse cultivation could accumulate DEHP in soils, and a higher soil FeOx content reduced the DnBP concentration. Based on a survey of vegetables in the diet, the hazard index of PAEs was 〈 0.15 for individuals in different cities. The exposure of PAEs through vegetable intake was higher than the total exposure from other food stuffS, inhalation, and dermal absorption. More attention should be g!ven to controlling PAEs in greenhouse vegetables.展开更多
文摘Density （ρ） and viscosity （η） measurements were carried out for 4-aminobutyric acid in 0.0041,0.0125 and 0.0207 mol·L-1 aqueous salbutamol sulphate at T=308.15,313.15 and 318.15K.The measured values of density and viscosity were used to estimate some important parameters such as apparent molar volume Vφ,limiting apparent molar volume Vφ0,transfer volume △Vφ0,hydration number Hn,second derivative of infinite dilution of partial molar volume with temperature 2Vφ0/T2,viscosity B-coefficients,variation of B with temperature dB/dT,free energy of activation per mole of solvent △μ10＊ and solute △μ20＊,activation entropy △S20＊ and activation enthalpy △H20＊ of the amino acids.These parameters have been interpreted in terms of solute-solute and solute-solvent interactions and structure making/breaking ability of solutes in the given solution.
基金Supported by the National Natural Science Foundation of China (No. 29976035).
文摘Excess molar volumes (V^E_m) of binary mixtures of2-methyl-3-buten-3-ol [CH_3C(OH)(CH_3)CHCG_2] with four 1-alcohols:methanol, ethanol, 1-propanol and l-butanol at 298.15 K andatmospheric pressure are derived from density measurements with avibrating-tube densimeter. All the excess volumes are negative in thesystems over the entire composition range. The results are correlatedwith the Redlich-Kister equation. The effects of chain length ofl-alcohols on V^E_m are discussed. The apparent molar volumes of2-methyl-3-ol and l-alcohols are calculated respectively.
基金part of which has been presented here,are sponsored by the National Natural Science Foundation of China(No.40246026).
文摘The present paper studies the sedimentary characteristics and mechanism of the shell ridges on the southwestern coast of Bohai Bay, which are the largest and have the highest shell (or shell fragment) content in the world. These shell ridges are composed of two sedimentary subfacies: the ridge subfacies and the ridge infill subfacies with different inner textures and sedimentary structures. The ridge subfacies primarily consists of fresh shells and/or shell fragments with parallel beddings and high-angle oblique beddings. The ridge infill subfacies consists of finer shell fragments and silty sand with parallel beddings oblique to land. The evolution of the shell ridge is controlled by the accumulation of substantial shell material,the relative slow erosion of shoreline, storm waves, winds and the shift of river routes. Wind tunnel tests indicate that the critical movement velocity of shell is lower than that of quartz sand of the same grain size. Deltaic progradation alternates with shell ridge growth. While the Yellow River empties into the sea through this area, accompanied by deltaic progradating, the shell material is scarce, which is unfavorable to the growth of the shell ridge. Conversely, erosion occurs along an abandoned delta coast where a shell ridge may develop, e.g. the shell ridge on the southwest of Bohai Bay.
基金Supported by the National Natural Science Foundation of China(21206002,21376016)the State Key Laboratory of Chemical Engineering(SKL-Ch E-13A03)
文摘The extraction fraction E and overall volumetric mass transfer coefficient kka of TBP extracting butyric acid pro- cess in confined impinging jet reactors （CIJR） with two jets were investigated. The main variables tested were the concentration of tri-butyl-phosphate （TBP） and butyric acid, the impinging velocity V, the impinging velocityratio of two phases Vorg/Vaq, the nozzle inner diameter di and the distance L between the jet axes and the top wall of the impinging chamber. The results showed that E and kLa increase with an increase of the impinging velocity V, the concentration ofTBP Corg, and the impinging velocity ratio Vor/Vaq. However, E and kta decrease with an increase of the inner diameter d1 from 1 to 2 mm, the concentration of butyric acid Caq from 0.5% （v/v） to 2% （v/v）. The factor L ranging from 3 to 11 mm has a negligible effect on E and kLa. A correlation on these variables and kLa was proposed based on the experimental data. These results indicated good mass transfer oerformance of CIJR in the extraction operation.
文摘The Jacobian elliptic function expansion method for nonlinear differential-different equations and its algorithm are presented by using some relations among ten Jacobian elliptic functions and successfully construct more new exact doubly-periodic solutions of the integrable discrete nonlinear Schrodinger equation. When the modulous m → 1or 0, doubly-periodic solutions degenerate to solitonic solutions including bright soliton, dark soliton, new solitons as well as trigonometric function solutions.
基金Project(21176264)supported by the National Natural Science Foundation of ChinaProject(ZL110414)supported by the Undergraduate Free Exploration Innovation Foundation of Central South University,China
文摘The production of environmental friendly emulsion paint is of great significance. Vacuum steam stripping of methyl isobutyl ketone （MIBK） and methyl ethyl ketone （MEK） from cathodic electrophoretic emulsion was studied. The effects of mass ratio of vapor to feed （V/F）, vacuum degree and feed temperature on removal rate of MIBK and MEK, emulsion size and solid volume fraction of the emulsion were investigated, and the removal of MIBK and MEK from cathodic electrophoretic emulsion by vacuum desorption was also studied. The results show that removal rates of both MIBK and MEK increase with the increase of V/F, vacuum degree and feed temperature. Removal rates of MIBK and MEK are 98.3% and 93.6%, respectively, at the operating condition V/F of 0.7, feed temperature of 27℃ and vacuum degree of 90 kPa. The emulsion size of cathodic electrophoretic emulsion increases slightly with feed temperature when temperature is below 42 ℃, and increases rapidly with feed temperature when temperature is above 42℃. Solid volume fraction increases by 10% as vacuum degree increases from 0 to 90 kPa at V/F of 0.7 and feed temperature of 27 ℃. Compared with vacuum desorption, vacuum steam stripping can get a higher removal rate of MIBK and MEK under the same feed flow, vacuum degree and feed temperature.
基金Supported by the National Natural Science Foundation of China(No.29736170,No.29976011)
文摘The infinite diluted activity coefficients of solvents in polyisopropyl methylacrylate was measured using inverse gas chromatography. The solvents used were benzene, toluene, ethyl benzene, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methanol, ethanol isopropyl alcohol, butyl alcohol, 1,2-dichloroethane, and chloroform. It was observed that the infinite diluted activity coefficient of alcohols are well above those of the other solvents investigated.
文摘EPD （electrophoretic deposition） of barium titanate from organic medium ethanol-PVB （polyvinyl butyral） was performed on Ni, Ti, steel substrate. Stable BaTiO3 suspensions with concentration of 2 wt.% have been prepared for the deposition. A uniform and dense layer was obtained for films deposited from ethanol with PVB of 0.1%. The surface topology of deposited films can be controlled via the applied voltage. This method allows to obtain crack-free and smooth layers BaTiO3 from organic medium with thickness of 4-20 μm.
基金Project(50621063) supported by the National Nature Science Foundation of ChinaProject(NCET-06-0691) supported by the Program for New Century Excellent Talents in University
文摘Di-n-butyl phthalate (DBP),one of phthalate acid esters (PAEs),was investigated to determine its biodegradation rate using Xiangjiang River sediment and find potential DBP degraders in the enrichment culture of the sediment. The sediment sample was incubated with an initial concentration of DBP of 100 mg/L for 5 d. The biodegradation rate of DBP was detected using HPLC and the degraded products were analyzed by GC/MS. Subsequently,the microbial diversity of the enrichment culture was analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results reveal that almost 100% of DBP is degraded after merely 3 d,generating two main degraded products:mono-butyl phthalate (MBP) and 9-octadecenoic acid. After a six-month enrichment period under the pressure of DBP,the dominant family in the final enrichment culture is clustered with the Comamonas sp.,the remaining are affiliated with Sphingomonas sp.,Hydrogenophaga sp.,Rhizobium sp.,and Acidovorax sp. The results show the potential of these bacteria to be used in the bioremediation of DBP in the environment.
基金supported by the National Basic Research Program of China (No. 2014CB441105)the National Natural Science Foundation of China (No. 21377136)+1 种基金the One Hundred Person Project of Chinese Academy of Sciences (No. 2012133)the 135 Research Program of Chinese Academy of Sciences
文摘Phthalate esters （PAEs）, which can disturb human endocrine system, have been widely detected in vegetable greenhouse agriculture in China. To investigate the effects of environmental factors on PAEs in soils, pollution sources were identified, and the cumulative risks of PAEs to humans through vegetables in the diet were evaluated in this study. Ninety-eight vegetable samples were collected from 10 markets along with 128 vegetable and 111 soil samples from agricultural greenhouses and open field. All soil and vegetable samples were contaminated with PAEs, and the total concentrations of the 5 PAEs, including dimethyl phthalate （DMP）, diethyl phthalate （DEP）, di-iso-butyl phthalate （DiBP）, di-n-butyl phthalate （DnBP）, and di-2-ethylhexyl phthalate （DEHP）, were in the ranges of 0.26-2.53 mg kg-1 for soils and 0.95-8.09 mg kg-1 for vegetables. Three components extracted from principle component analysis could explain 51.2%, 19.8%, and 15.3% of the total variance of the 5 PAEs in soils, which may represent three major sources of PAEs, i.e., wastewater irrigation, application of fertilizers and pesticides, and plastic film. Long-term greenhouse cultivation could accumulate DEHP in soils, and a higher soil FeOx content reduced the DnBP concentration. Based on a survey of vegetables in the diet, the hazard index of PAEs was 〈 0.15 for individuals in different cities. The exposure of PAEs through vegetable intake was higher than the total exposure from other food stuffS, inhalation, and dermal absorption. More attention should be g!ven to controlling PAEs in greenhouse vegetables.
