Hydrothermal carbon（HC） was prepared from walnut shells, which are abundant in Northeastern China. The prepared HC was used as a precursor to produce mtric acid modified carbon（MC）. The hydrothermal carbonization ...Hydrothermal carbon（HC） was prepared from walnut shells, which are abundant in Northeastern China. The prepared HC was used as a precursor to produce mtric acid modified carbon（MC）. The hydrothermal carbonization included dehydration and decarboxylation processes wherein the hemicellulose was completely decomposed and the celhilose was partly decomposed, with some oxygen-containing functional groups being produced. The aromati- city, specific surface area and pore content of the HC increased, but its polarity decreased. With 6 mol/L nitric acid and a modification time of 15 min, the specific surface area and pore content decreased, but the proportion of oxy- gen-containing fimctional groups on the surface increased significantly, thereby improving the dye adsorption performance. The adsorption of methylene blue and malachite green was best desclibed by the pseudo-second-order kinetic and Langmuir isotherm models. The adsorption capacity of MC was determined to be much larger than that of HC.展开更多
In an acetic acid–sodium acetate buffer solution of pH 3.6–6.8, a compound complex was formed between sodium hyaluronate (abbreviated as SH) and some basic bisphenylnaphthylmethane dyes, leading to a great enhanceme...In an acetic acid–sodium acetate buffer solution of pH 3.6–6.8, a compound complex was formed between sodium hyaluronate (abbreviated as SH) and some basic bisphenylnaphthylmethane dyes, leading to a great enhancement of the intensity of resonance Rayleigh scattering (RRS) and giving a new RRS spectrum, with its maximum scattering peak near 280 nm. It was also found that the intensity of RRS was directly proportional to the concentration of SH near the range between 0 and 3.0 mg/L. Based on these facts, a sensitive method for the determination of SH has been established. The method had good selectivity, and has been used for the determination of total amounts of SH in samples with satisfactory results. For the NB–SH system, the detection limit of SH was down to 13.7 ng/mL.展开更多
In this work, a sensitive, rapid and simple method for the determination of trace amounts of potassium ferrocyanide in salinized foods and table salt using EV as a RRS probe is established. The detection limit （3σ）...In this work, a sensitive, rapid and simple method for the determination of trace amounts of potassium ferrocyanide in salinized foods and table salt using EV as a RRS probe is established. The detection limit （3σ） of the EV system is 7.8 ng/mL. This new method is more suitable for the determination of the trace amounts of potassium ferrocyanide in colour salinized foods and it can not be disturbed by the color of salinized foods.展开更多
In the present work,novel dual-functionalized hollow polymer particles （DF-HPP） with high density of carboxylate and amino dual functional groups have been specially designed and fabricated to serve as high-performa...In the present work,novel dual-functionalized hollow polymer particles （DF-HPP） with high density of carboxylate and amino dual functional groups have been specially designed and fabricated to serve as high-performance adsorbent for selective removal of basic dye （methylene blue,b-MB,as a model dye）.Due to both the high surface area and the extremely high density of carboxylate and amino groups,the DF-HPPs exhibited excellent adsorption property for methylene blue （b-MB）,including high adsorption capacity,fast adsorption/desorption rates,unique pH-sensitivity and easy recovery.The equilibrium adsorption data of b-MB on the DF-HPPs were evaluated using Freundlich and Langmuir isotherm models,and the equilibrium isotherm was better fit with Langmuir model with a maximum adsorption capacity of 538.8 mg/g at pH 12.More interestingly,the DF-HPPs showed a significant pH-dependent equilibrium adsorption capacity,which decreased dramatically from 516.1 mg/g to 24 mg/g as the solution pH decreased from 12 to 3.The dye-adsorbed DF-HPPs can be facilely and rapidly regenerated under mild condition （under weak acidic solution,pH 3,in 30 min） to recover both b-MB and the DF-HPPs,and the regenerated DF-HPPs can be reused for dye removal with high efficiency,indicating the exceptional recyclability of the DF-HPPs.展开更多
The ion transfer of the basic dye rhodamine B at the interface between water and nitro- benzene,water and 1,2-dichloroethane,as well as water and nitrobenzene-chlorobenzene mixtures has been studied by cyclic voltamme...The ion transfer of the basic dye rhodamine B at the interface between water and nitro- benzene,water and 1,2-dichloroethane,as well as water and nitrobenzene-chlorobenzene mixtures has been studied by cyclic voltammetry and chronopotentiometry with linear current scanning.A transfer mechanism of rhodamine B is proposed in terms of its electrochemical behavior,dissociation and distribution equilibria,and is ascribed as diffusion-controlled reversible process of rhodamine B.The ex- perimental data obtained for the relationship between interfacial half-wave potential ° and pH are in agreement with the theoretical equation based on the mechanism,and the standard interracial potential differences °and standard Gibbs energies G°are calculated by extrapolation.The effect of the nature of solvent on the transfer behavior and the stability of the interface have been dis- cussed.展开更多
文摘Hydrothermal carbon（HC） was prepared from walnut shells, which are abundant in Northeastern China. The prepared HC was used as a precursor to produce mtric acid modified carbon（MC）. The hydrothermal carbonization included dehydration and decarboxylation processes wherein the hemicellulose was completely decomposed and the celhilose was partly decomposed, with some oxygen-containing functional groups being produced. The aromati- city, specific surface area and pore content of the HC increased, but its polarity decreased. With 6 mol/L nitric acid and a modification time of 15 min, the specific surface area and pore content decreased, but the proportion of oxy- gen-containing fimctional groups on the surface increased significantly, thereby improving the dye adsorption performance. The adsorption of methylene blue and malachite green was best desclibed by the pseudo-second-order kinetic and Langmuir isotherm models. The adsorption capacity of MC was determined to be much larger than that of HC.
文摘In an acetic acid–sodium acetate buffer solution of pH 3.6–6.8, a compound complex was formed between sodium hyaluronate (abbreviated as SH) and some basic bisphenylnaphthylmethane dyes, leading to a great enhancement of the intensity of resonance Rayleigh scattering (RRS) and giving a new RRS spectrum, with its maximum scattering peak near 280 nm. It was also found that the intensity of RRS was directly proportional to the concentration of SH near the range between 0 and 3.0 mg/L. Based on these facts, a sensitive method for the determination of SH has been established. The method had good selectivity, and has been used for the determination of total amounts of SH in samples with satisfactory results. For the NB–SH system, the detection limit of SH was down to 13.7 ng/mL.
基金supported by the National Natural Science Foundation of China(No.20475045)Scientific Research Foundation of Bureau of Quality and Technical Supervision of China(No.2005 J0095).
文摘In this work, a sensitive, rapid and simple method for the determination of trace amounts of potassium ferrocyanide in salinized foods and table salt using EV as a RRS probe is established. The detection limit （3σ） of the EV system is 7.8 ng/mL. This new method is more suitable for the determination of the trace amounts of potassium ferrocyanide in colour salinized foods and it can not be disturbed by the color of salinized foods.
文摘In the present work,novel dual-functionalized hollow polymer particles （DF-HPP） with high density of carboxylate and amino dual functional groups have been specially designed and fabricated to serve as high-performance adsorbent for selective removal of basic dye （methylene blue,b-MB,as a model dye）.Due to both the high surface area and the extremely high density of carboxylate and amino groups,the DF-HPPs exhibited excellent adsorption property for methylene blue （b-MB）,including high adsorption capacity,fast adsorption/desorption rates,unique pH-sensitivity and easy recovery.The equilibrium adsorption data of b-MB on the DF-HPPs were evaluated using Freundlich and Langmuir isotherm models,and the equilibrium isotherm was better fit with Langmuir model with a maximum adsorption capacity of 538.8 mg/g at pH 12.More interestingly,the DF-HPPs showed a significant pH-dependent equilibrium adsorption capacity,which decreased dramatically from 516.1 mg/g to 24 mg/g as the solution pH decreased from 12 to 3.The dye-adsorbed DF-HPPs can be facilely and rapidly regenerated under mild condition （under weak acidic solution,pH 3,in 30 min） to recover both b-MB and the DF-HPPs,and the regenerated DF-HPPs can be reused for dye removal with high efficiency,indicating the exceptional recyclability of the DF-HPPs.
基金The support of the National Natural Science Foundation of China is gratefully acknowledged.
文摘The ion transfer of the basic dye rhodamine B at the interface between water and nitro- benzene,water and 1,2-dichloroethane,as well as water and nitrobenzene-chlorobenzene mixtures has been studied by cyclic voltammetry and chronopotentiometry with linear current scanning.A transfer mechanism of rhodamine B is proposed in terms of its electrochemical behavior,dissociation and distribution equilibria,and is ascribed as diffusion-controlled reversible process of rhodamine B.The ex- perimental data obtained for the relationship between interfacial half-wave potential ° and pH are in agreement with the theoretical equation based on the mechanism,and the standard interracial potential differences °and standard Gibbs energies G°are calculated by extrapolation.The effect of the nature of solvent on the transfer behavior and the stability of the interface have been dis- cussed.
