An ionic conductivity prediction equation at low concentration for two acid salts is proposed taking into account the dissociation and association equilibria among ions. The salts considered are sodium and potassium h...An ionic conductivity prediction equation at low concentration for two acid salts is proposed taking into account the dissociation and association equilibria among ions. The salts considered are sodium and potassium hydrogen tartrates. There is no additional parameter of high order terms except for the Onsager's coefficient of limited term in the new equation. Results show a complex conductance of acidic tartrates in aqueous solution. The molar conductivities of metal ions are nearly constant such that the contributions from hydrogen and tartrate ions decrease with concentration, while the molar conductivity of bitartrate ion increases with concentration.展开更多
The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the e...The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the effects of reaction parameters on leaching rate. The leaching rate increases with reaction temperature, concentrations of H 2 SO 4 and organic matter in molasses alcohol wastewater increase and ore particle size decreases. The leaching process follows the kinetics of a shrinking core model and the apparent activation energy is 57.5 kJ·mol –1 . The experimental results indicate a reaction order of 0.52 for H2SO4 concentration and 0.90 for chemical oxygen demand (COD) of molasses alcohol wastewater. It is concluded that the reductive leaching of pyrolusite with molasses alcohol wastewater is controlled by the diffusion through the ash/inert layer composed of the associated minerals.展开更多
Objective: To study the relationship between the amount of consumed alcohol, blood alcohol concentration (BAC), and driving ability among a part of the population in Southwest China and to provide reference for the fo...Objective: To study the relationship between the amount of consumed alcohol, blood alcohol concentration (BAC), and driving ability among a part of the population in Southwest China and to provide reference for the formulation of the legal limits for safe driving. Methods: Seventy-six randomly selected volunteer drivers each had three times of alcohol intake (100 ml each time). After each drank, BAC was measured with gas chromatograph and driving ability was evaluated. The drivers were grouped according to age, weight, alcohol tolerance and driving experience respectively and changes in BAC and driving ability were analyzed. Results: Average BAC and the percentage of drivers showing impaired driving ability in the groups increased after each intake of 100 ml alcohol. BAC in Group≤60 kg was more susceptible to alcohol than that in Group>60 kg. When each drank, alcohol had greater influence on drivers who had comparatively shorter driving experience. Conclusion: Volume of consumed alcohol, BAC and driving ability have direct associations among one another and are all under the influence of various factors including individual conditions. To set an appropriate legal BAC limit for safe driving should take an overall consideration of all factors.展开更多
In this paper, we report on the comprehensive alcohol-/ion-responsive properties of a smart copolymer poly(N- isopropylacry]amide-co-benzo-18-crown-6-acrylamide) (P(NIPAM-co-BCAm)). The orthogonal design method ...In this paper, we report on the comprehensive alcohol-/ion-responsive properties of a smart copolymer poly(N- isopropylacry]amide-co-benzo-18-crown-6-acrylamide) (P(NIPAM-co-BCAm)). The orthogonal design method is adopted for experimental design. The experimental results show that alcohol can trigger the shrinking and Ba2t can induce the swelling of the P(NIPAM-co-BCAm) copolymer. According to the phase transition tempera- ture (LCST) change results of the copolymer, the influence of variables on the LCST changes weakens in the following order: alcohol concentration 〉 alcohol species 〉 metal ion species 〉 BCAm concentration 〉 ion concentration. The larger the alcohol concentration and the larger the molecular size of alcohols, the lower the LCST value; on the contrary, the more the BCAm content in the copolymer or the larger the BCAm/ion complex stability constant (IgK) or the larger the ion concentration is, the higher the LCST value. For a P(NIPAM-co-BCAm ) copolymer with a fixed BCAm content, a binary function of ion concentration and IgK of BCAm/ion is developed to precisely predict the LCST values of the copolymer in different metal ion solutions. The results provide valuable information for fabricating artificial biomimetic G-protein-gated inwardly rectifying potassium (GIRK) channels that are activated by alcohol and inhibited by Ba2+.展开更多
To establish a theoretical foundation for simultaneous removal of multi-heavy metals,the adsorption of Cu(Ⅱ) and Pb(Ⅱ) ions from their single and binary systems by Ca-alginate immobilized activated carbon and Sa...To establish a theoretical foundation for simultaneous removal of multi-heavy metals,the adsorption of Cu(Ⅱ) and Pb(Ⅱ) ions from their single and binary systems by Ca-alginate immobilized activated carbon and Saccharomyces cerevisiae (CAS) was investigated.The CAS beads were characterized by Scanning electron microscope (SEM) and Fourier transformed infrared spectroscopy (FTTR).The effect of initial pH,adsorbent dosage,contact time and initial metal ions concentration on the adsorption process was systematically investigated.The experimental maximum contents of Cu(Ⅱ) and Pb(Ⅱ) uptake capacity were determined as 64.90 and 166.31 mg/g,respectively.The pseudo-second-order rate equation and Langmuir isotherm model could explain respectively the kinetic and isotherm experimental data of Cu(Ⅱ) and Pb(Ⅱ) ions in single-component systems with much satisfaction.The experimental adsorption data of Cu(Ⅱ) and Pb(Ⅱ) ions in binary system were best described by the extended Freundlich isotherm and the extended Langmuir isotherm,respectively.The removal of Cu(lⅡ) ions was more significantly influenced by the presence of the coexistent Pb(Ⅱ) species,while the Pb(Ⅱ) removal was affected slightly by varying the initial concentration of Cu(Ⅱ).The CAS was successfully regenerated using 1 mol/L HNO3 solution.展开更多
基金Supported by the National Natural Science Foundation of China(No.29736170)
文摘An ionic conductivity prediction equation at low concentration for two acid salts is proposed taking into account the dissociation and association equilibria among ions. The salts considered are sodium and potassium hydrogen tartrates. There is no additional parameter of high order terms except for the Onsager's coefficient of limited term in the new equation. Results show a complex conductance of acidic tartrates in aqueous solution. The molar conductivities of metal ions are nearly constant such that the contributions from hydrogen and tartrate ions decrease with concentration, while the molar conductivity of bitartrate ion increases with concentration.
基金Supported by the National Natural Science Foundation of China (20866001) the Natural Science Foundation of GuangxiProvince (0832035)
文摘The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the effects of reaction parameters on leaching rate. The leaching rate increases with reaction temperature, concentrations of H 2 SO 4 and organic matter in molasses alcohol wastewater increase and ore particle size decreases. The leaching process follows the kinetics of a shrinking core model and the apparent activation energy is 57.5 kJ·mol –1 . The experimental results indicate a reaction order of 0.52 for H2SO4 concentration and 0.90 for chemical oxygen demand (COD) of molasses alcohol wastewater. It is concluded that the reductive leaching of pyrolusite with molasses alcohol wastewater is controlled by the diffusion through the ash/inert layer composed of the associated minerals.
文摘Objective: To study the relationship between the amount of consumed alcohol, blood alcohol concentration (BAC), and driving ability among a part of the population in Southwest China and to provide reference for the formulation of the legal limits for safe driving. Methods: Seventy-six randomly selected volunteer drivers each had three times of alcohol intake (100 ml each time). After each drank, BAC was measured with gas chromatograph and driving ability was evaluated. The drivers were grouped according to age, weight, alcohol tolerance and driving experience respectively and changes in BAC and driving ability were analyzed. Results: Average BAC and the percentage of drivers showing impaired driving ability in the groups increased after each intake of 100 ml alcohol. BAC in Group≤60 kg was more susceptible to alcohol than that in Group>60 kg. When each drank, alcohol had greater influence on drivers who had comparatively shorter driving experience. Conclusion: Volume of consumed alcohol, BAC and driving ability have direct associations among one another and are all under the influence of various factors including individual conditions. To set an appropriate legal BAC limit for safe driving should take an overall consideration of all factors.
基金Supported by the National Natural Science Foundation of China(21136006)the Foundation for the Author of National Excellent Doctoral Dissertation of PR China(201163)the National High Technology Research and Development Program(2012AA021403)
文摘In this paper, we report on the comprehensive alcohol-/ion-responsive properties of a smart copolymer poly(N- isopropylacry]amide-co-benzo-18-crown-6-acrylamide) (P(NIPAM-co-BCAm)). The orthogonal design method is adopted for experimental design. The experimental results show that alcohol can trigger the shrinking and Ba2t can induce the swelling of the P(NIPAM-co-BCAm) copolymer. According to the phase transition tempera- ture (LCST) change results of the copolymer, the influence of variables on the LCST changes weakens in the following order: alcohol concentration 〉 alcohol species 〉 metal ion species 〉 BCAm concentration 〉 ion concentration. The larger the alcohol concentration and the larger the molecular size of alcohols, the lower the LCST value; on the contrary, the more the BCAm content in the copolymer or the larger the BCAm/ion complex stability constant (IgK) or the larger the ion concentration is, the higher the LCST value. For a P(NIPAM-co-BCAm ) copolymer with a fixed BCAm content, a binary function of ion concentration and IgK of BCAm/ion is developed to precisely predict the LCST values of the copolymer in different metal ion solutions. The results provide valuable information for fabricating artificial biomimetic G-protein-gated inwardly rectifying potassium (GIRK) channels that are activated by alcohol and inhibited by Ba2+.
基金Project(11JJ2031)supported by the Key Project of Natural Science Foundation of Hunan Province,China
文摘To establish a theoretical foundation for simultaneous removal of multi-heavy metals,the adsorption of Cu(Ⅱ) and Pb(Ⅱ) ions from their single and binary systems by Ca-alginate immobilized activated carbon and Saccharomyces cerevisiae (CAS) was investigated.The CAS beads were characterized by Scanning electron microscope (SEM) and Fourier transformed infrared spectroscopy (FTTR).The effect of initial pH,adsorbent dosage,contact time and initial metal ions concentration on the adsorption process was systematically investigated.The experimental maximum contents of Cu(Ⅱ) and Pb(Ⅱ) uptake capacity were determined as 64.90 and 166.31 mg/g,respectively.The pseudo-second-order rate equation and Langmuir isotherm model could explain respectively the kinetic and isotherm experimental data of Cu(Ⅱ) and Pb(Ⅱ) ions in single-component systems with much satisfaction.The experimental adsorption data of Cu(Ⅱ) and Pb(Ⅱ) ions in binary system were best described by the extended Freundlich isotherm and the extended Langmuir isotherm,respectively.The removal of Cu(lⅡ) ions was more significantly influenced by the presence of the coexistent Pb(Ⅱ) species,while the Pb(Ⅱ) removal was affected slightly by varying the initial concentration of Cu(Ⅱ).The CAS was successfully regenerated using 1 mol/L HNO3 solution.