The solubilities of isophthalic acid （1） in binary acetic acid （2） ＋ water （3） solvent mixtures were determined in a pressurized vessel. The temperature range was from 373.2 to 473.2K and the range of the mole ...The solubilities of isophthalic acid （1） in binary acetic acid （2） ＋ water （3） solvent mixtures were determined in a pressurized vessel. The temperature range was from 373.2 to 473.2K and the range of the mole fraction of acetic acid in the solvent mixtures was from x2 = 0 to 1. A new method to measure the solubility was developed, which solved the problem of sampling at high temperature. The experimental results indicated that within the temperature range studied, the solubilities of isophthalic acid in all mixtures showed an increasing trend with increasing tem- perature. The expe^mental solubilities were co .rrelated by the Buchowski equation, and the calculate results showed good agreement with the experimental solubilities. Furthermore, the mixed solvent systems were found to exhibit a maximum solubility effect on the solubility, which may be attributed to the intermolecular association between the solute and the solvent mixture： The maximum solubility effect was well modeled by the modified Wilson equation.展开更多
Pervaporation separation of water-acetic acid mixtures through Poly(AN-co-AA) membranes and rare earth metal ions treated Poly(AN-co-AA)membranes was investigated for the first time. The results showed that the treatm...Pervaporation separation of water-acetic acid mixtures through Poly(AN-co-AA) membranes and rare earth metal ions treated Poly(AN-co-AA)membranes was investigated for the first time. The results showed that the treatment with rare earth metal ions could greatly improve the characteristics of the separation of water-acetic acid mixtures.展开更多
AIM: To investigate the usefulness of chromoendoscopy, using an acetic acid indigocarmine mixture (AIM), for gastric adenoma diagnosed by forceps biopsy.
A new separation method, reactive extractive distillation, was put forward for separating water and acetic acid. The separation mechanism was analyzed through infrared spectra technique. Isobaric vapor-liquid equilibr...A new separation method, reactive extractive distillation, was put forward for separating water and acetic acid. The separation mechanism was analyzed through infrared spectra technique. Isobaric vapor-liquid equilibrium (VLE) data at 101.33 kPa for the binary or ternary systems consisting of water, acetic acid and tributylamine were measured. The activity coefficients were correlated by using Wilson, NRTL, and UNIQUAC Equations.The VLE experiment showed that tributylamine could enhance the relative volatility of water to acetic acid. An extractive distillation experiment was carried out and proved that tributylamine was a good extractive solvent.展开更多
Isobaric vapor-liquid equilibrium(VLE) data for acetic acid + sec-butyl acetate and water+acetic acid + sec-butyl acetate systems were determined at 101.3 kPa using a modified Rose type.The nonideality of the vapor ph...Isobaric vapor-liquid equilibrium(VLE) data for acetic acid + sec-butyl acetate and water+acetic acid + sec-butyl acetate systems were determined at 101.3 kPa using a modified Rose type.The nonideality of the vapor phase caused by the association of the acetic acid was corrected by the chemical theory and Hayden-O'Connell method.Thermodynamic consistency was tested for the binary VLE data.The experimental data were correlated successfully with the Non-Random Two Liquids(NRTL) model.The Root Mean Square Deviation(RMSD) of the ternary system was 0.0038.The saturation vapor pressure of sec-butyl acetate at 329 to 385 K was measured by means of two connected equilibrium cells.The vapor pressures of water and sec-butyl acetate were correlated with the Antoine equation.The binary interaction parameters and the ternary VLE data were obtained from this work.展开更多
The copolymer of acrylic acid and acrylonitrile has been synthesized and pervaporation properties of the copolymeric membranes have been investigated. In order to elucidate the influence of membrane-permeate interacti...The copolymer of acrylic acid and acrylonitrile has been synthesized and pervaporation properties of the copolymeric membranes have been investigated. In order to elucidate the influence of membrane-permeate interaction on the pervaporation of water-ethanol mixtures and to prepare much improved membranes, the membranes have been treated with alkali metal, alkali earth metal and transition metal salt aqueous solutions. The treated membranes (ionized membranes) exhibited higher separation factors than the untreated membranes. The separation factors of various alkali metal cation membranes decreased in the following order : Li^+>Na^+>K^+, and the permeation rates showed an opposite tendency. The dependence of pervaporation behavior on the copolymer composition ,feed concentration and operating temperature have been studied with both ionized and non-ionized membranes. The apparent activation energies of water and ethanol permeation were calculated.展开更多
The acetic acid-water binary system is a classical hydroxy-carboxy mixed system, while new and interesting phenomena appear under stimulated Raman scattering(SRS).Compared with the weaker signal of the acetic acid-wat...The acetic acid-water binary system is a classical hydroxy-carboxy mixed system, while new and interesting phenomena appear under stimulated Raman scattering(SRS).Compared with the weaker signal of the acetic acid-water binary system obtained in spontaneous Raman scattering, SRS provides a finer band and a relatively distinct structural transition point.The structural transformation points are respectively at 30% and 80% by volume ratio under the condition of spontaneous Raman spectroscopy, while they are respectively at 15% and 25% under the condition of SRS.This phenomenon is attributed to the generation of laser induced plasma and shockwave induced dynamic high pressure environment during SRS.展开更多
Peroxyoxalate chemiluminescence was, for the first time, examined by using ternary mixed solutions of water-hydrophilic/hydrophobic organic solvent. Eosin Y as a model fluorescence compound was dissolved with the tern...Peroxyoxalate chemiluminescence was, for the first time, examined by using ternary mixed solutions of water-hydrophilic/hydrophobic organic solvent. Eosin Y as a model fluorescence compound was dissolved with the ternary solutions of water (1.0 mM carbonate buffer, pH 9.0)-acetonitrile-ethyl acetate, water-rich of 15:3:2 volume ratio and organic solvent-rich of 3:8:4 volume ratio, to which bis(2,4,6-trichlorophenyl) oxalate and hydrogen peroxide chemiluminescence reagent were added. The chemiluminescence observed with the ternary solutions, especially the organic solvent-rich solution, showed a larger signal than that observed with the water only solution or water-acetonitrile mixed solution. Chemiluminescence in the presence of twenty types of α-amino acid was similarly examined by using the ternary organic solvent-rich solution. The chemiluminescence of three α-amino acids with fluorescence properties was enhanced with the ternary solution. The data reported here may contribute to development of a new, sensitive peroxyoxalate chemiluminescence detection system.展开更多
Acetic acid is a simple and universal compound found in various organisms.Recently,acetic acid was found to play an essential role in conferring tolerance to water deficit stress in plants.This novel mechanism of drou...Acetic acid is a simple and universal compound found in various organisms.Recently,acetic acid was found to play an essential role in conferring tolerance to water deficit stress in plants.This novel mechanism of drought stress tolerance mediated by acetic acid via networks involving phytohormones,genes,and chromatin regulation has great potential for solving the global food crisis and preventing desertification caused by global warming.We highlight the functions of acetic acid in conferring tolerance to water deficit stress.展开更多
Fluorescence spectra of acetic acid-water solution excited by ultraviolet （UV） light are studied, and the relationship between fluorescence spectra and molecular association of acetic acid is discussed. The results ...Fluorescence spectra of acetic acid-water solution excited by ultraviolet （UV） light are studied, and the relationship between fluorescence spectra and molecular association of acetic acid is discussed. The results indicate that when the exciting light wavelength is longer than 246 nm, there are two fluorescence peaks located at 305 and 334 nm, respectively. By measuring the excitation spectra, the optimal wavelengths of the two fluorescence peaks are obtained, which are 258 and 284 nm, respectively. Fluorescence spectra of acetic acid-water solution change with concentrations, which is primarily attributed to changes of molecular association of acetic acid in aqueous solution. Through theoretical analysis, three variations of molecular association have been obtained in acetic acid-water solution, which are the hydrated monomers, the linear dimers, and the water separated dimers. This research can provide references to studies of molecular association of acetic acid-water, especiMly studies of hydrogen bonds.展开更多
The mechanism for the production of acetic acid from ethanol and water mixture catalyzed by iridium catalyst has been theoretically investigated.The cooperation of the iridium center and bpyO ligand is highlighted,whi...The mechanism for the production of acetic acid from ethanol and water mixture catalyzed by iridium catalyst has been theoretically investigated.The cooperation of the iridium center and bpyO ligand is highlighted,which plays an important role in the catalytic activity.The hydrogen release from the iridium center is the rate-determining step,with an energy barrier of 22.5 kcal/mol.The electronic structure analysis suggests electron-donating substituents could decrease the energy barrier.展开更多
基金Supported by the Natural Science Foundation of Zhejiang Province, China （Z4100351） and the Fundamental Research Funds for the Central Universities （2013QNA4035）.
文摘The solubilities of isophthalic acid （1） in binary acetic acid （2） ＋ water （3） solvent mixtures were determined in a pressurized vessel. The temperature range was from 373.2 to 473.2K and the range of the mole fraction of acetic acid in the solvent mixtures was from x2 = 0 to 1. A new method to measure the solubility was developed, which solved the problem of sampling at high temperature. The experimental results indicated that within the temperature range studied, the solubilities of isophthalic acid in all mixtures showed an increasing trend with increasing tem- perature. The expe^mental solubilities were co .rrelated by the Buchowski equation, and the calculate results showed good agreement with the experimental solubilities. Furthermore, the mixed solvent systems were found to exhibit a maximum solubility effect on the solubility, which may be attributed to the intermolecular association between the solute and the solvent mixture： The maximum solubility effect was well modeled by the modified Wilson equation.
基金This work was supported by the Zhejiang Provincial Natural Science Foundation and the Chinese University Doctoral Fund
文摘Pervaporation separation of water-acetic acid mixtures through Poly(AN-co-AA) membranes and rare earth metal ions treated Poly(AN-co-AA)membranes was investigated for the first time. The results showed that the treatment with rare earth metal ions could greatly improve the characteristics of the separation of water-acetic acid mixtures.
文摘AIM: To investigate the usefulness of chromoendoscopy, using an acetic acid indigocarmine mixture (AIM), for gastric adenoma diagnosed by forceps biopsy.
文摘A new separation method, reactive extractive distillation, was put forward for separating water and acetic acid. The separation mechanism was analyzed through infrared spectra technique. Isobaric vapor-liquid equilibrium (VLE) data at 101.33 kPa for the binary or ternary systems consisting of water, acetic acid and tributylamine were measured. The activity coefficients were correlated by using Wilson, NRTL, and UNIQUAC Equations.The VLE experiment showed that tributylamine could enhance the relative volatility of water to acetic acid. An extractive distillation experiment was carried out and proved that tributylamine was a good extractive solvent.
基金Supported by the National Natural Science Foundation of China （21176049） and the Natural Science Foundation of Fujian Province （2012J01034）.
文摘Isobaric vapor-liquid equilibrium(VLE) data for acetic acid + sec-butyl acetate and water+acetic acid + sec-butyl acetate systems were determined at 101.3 kPa using a modified Rose type.The nonideality of the vapor phase caused by the association of the acetic acid was corrected by the chemical theory and Hayden-O'Connell method.Thermodynamic consistency was tested for the binary VLE data.The experimental data were correlated successfully with the Non-Random Two Liquids(NRTL) model.The Root Mean Square Deviation(RMSD) of the ternary system was 0.0038.The saturation vapor pressure of sec-butyl acetate at 329 to 385 K was measured by means of two connected equilibrium cells.The vapor pressures of water and sec-butyl acetate were correlated with the Antoine equation.The binary interaction parameters and the ternary VLE data were obtained from this work.
文摘The copolymer of acrylic acid and acrylonitrile has been synthesized and pervaporation properties of the copolymeric membranes have been investigated. In order to elucidate the influence of membrane-permeate interaction on the pervaporation of water-ethanol mixtures and to prepare much improved membranes, the membranes have been treated with alkali metal, alkali earth metal and transition metal salt aqueous solutions. The treated membranes (ionized membranes) exhibited higher separation factors than the untreated membranes. The separation factors of various alkali metal cation membranes decreased in the following order : Li^+>Na^+>K^+, and the permeation rates showed an opposite tendency. The dependence of pervaporation behavior on the copolymer composition ,feed concentration and operating temperature have been studied with both ionized and non-ionized membranes. The apparent activation energies of water and ethanol permeation were calculated.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11574113,11374123,and 11104106)Science and Technology Planning Project of Jilin Province,China(Grant Nos.20180101238JC,20170204076GX,20180101006JC,20190103041JH,and 20190201260JC)Post-Doctoral Innovative Talent Support Program,China(Grant Nos.BX20180127 and 2019M651192)
文摘The acetic acid-water binary system is a classical hydroxy-carboxy mixed system, while new and interesting phenomena appear under stimulated Raman scattering(SRS).Compared with the weaker signal of the acetic acid-water binary system obtained in spontaneous Raman scattering, SRS provides a finer band and a relatively distinct structural transition point.The structural transformation points are respectively at 30% and 80% by volume ratio under the condition of spontaneous Raman spectroscopy, while they are respectively at 15% and 25% under the condition of SRS.This phenomenon is attributed to the generation of laser induced plasma and shockwave induced dynamic high pressure environment during SRS.
文摘Peroxyoxalate chemiluminescence was, for the first time, examined by using ternary mixed solutions of water-hydrophilic/hydrophobic organic solvent. Eosin Y as a model fluorescence compound was dissolved with the ternary solutions of water (1.0 mM carbonate buffer, pH 9.0)-acetonitrile-ethyl acetate, water-rich of 15:3:2 volume ratio and organic solvent-rich of 3:8:4 volume ratio, to which bis(2,4,6-trichlorophenyl) oxalate and hydrogen peroxide chemiluminescence reagent were added. The chemiluminescence observed with the ternary solutions, especially the organic solvent-rich solution, showed a larger signal than that observed with the water only solution or water-acetonitrile mixed solution. Chemiluminescence in the presence of twenty types of α-amino acid was similarly examined by using the ternary organic solvent-rich solution. The chemiluminescence of three α-amino acids with fluorescence properties was enhanced with the ternary solution. The data reported here may contribute to development of a new, sensitive peroxyoxalate chemiluminescence detection system.
基金supported by grants from JSPS KAKENHI(no.19H00937 and no.20H03022 to J-M.K)Bio-oriented Technology Research Advancement Institution(BRAIN)(no.JPJ010717 to J-M.K)the New Energy and Industrial Technology Development Organization(NEDO)(no.JPNP20011 to J-M.K,).
文摘Acetic acid is a simple and universal compound found in various organisms.Recently,acetic acid was found to play an essential role in conferring tolerance to water deficit stress in plants.This novel mechanism of drought stress tolerance mediated by acetic acid via networks involving phytohormones,genes,and chromatin regulation has great potential for solving the global food crisis and preventing desertification caused by global warming.We highlight the functions of acetic acid in conferring tolerance to water deficit stress.
基金supported by the Natural Science Foundation of Jiangsu Province (No. BK2007204)the Natural Science Foundation of Jiangsu Province Educational Committee (No. 07KJD140208).
文摘Fluorescence spectra of acetic acid-water solution excited by ultraviolet （UV） light are studied, and the relationship between fluorescence spectra and molecular association of acetic acid is discussed. The results indicate that when the exciting light wavelength is longer than 246 nm, there are two fluorescence peaks located at 305 and 334 nm, respectively. By measuring the excitation spectra, the optimal wavelengths of the two fluorescence peaks are obtained, which are 258 and 284 nm, respectively. Fluorescence spectra of acetic acid-water solution change with concentrations, which is primarily attributed to changes of molecular association of acetic acid in aqueous solution. Through theoretical analysis, three variations of molecular association have been obtained in acetic acid-water solution, which are the hydrated monomers, the linear dimers, and the water separated dimers. This research can provide references to studies of molecular association of acetic acid-water, especiMly studies of hydrogen bonds.
基金This work is supported by the National Natural Science Foundation of China (No. 21672018)the Fundamental Research Funds for the Central Universities (No. XK1802-6). We thank the National Supercomputing Center in Tianjin (TianHe-1) for providing part of the computational sources.
文摘The mechanism for the production of acetic acid from ethanol and water mixture catalyzed by iridium catalyst has been theoretically investigated.The cooperation of the iridium center and bpyO ligand is highlighted,which plays an important role in the catalytic activity.The hydrogen release from the iridium center is the rate-determining step,with an energy barrier of 22.5 kcal/mol.The electronic structure analysis suggests electron-donating substituents could decrease the energy barrier.
