The work herein employed a rotating packed bed(RPB)to intensify the sulfonation process of 1,4-diaminoanthraquinone leuco(DL)in an attempt to improve the yield of the product 1,4-diaminoanthra quinone-2-sulfonic acid(...The work herein employed a rotating packed bed(RPB)to intensify the sulfonation process of 1,4-diaminoanthraquinone leuco(DL)in an attempt to improve the yield of the product 1,4-diaminoanthra quinone-2-sulfonic acid(DSA).First,the effects of operating conditions in a stirred tank reactor(STR),including stirring speed,chlorosulfonic acid/DL molar ratio(η),solvent/DL mass ratio(ζ),reaction temperature and dropping speed of chlorosulfonic acid,on the yield of DSA were investigated.The yield of DSA can reach 87.34%under the optimal operating conditions:stirring speed of 500 r·min^(-1),ηof 4.5,ζof 7,reaction temperature of 150℃,dropping speed of 0.61 ml·min^(-1).In addition,the kinetics of the sulfonation process via the shrinking core model revealed that the reaction is controlled by diffusion via a product layer under the reaction temperature of 140℃.Furthermore,the RPB was employed to intensify the mass transfer between liquid and solid phases during the sulfonation reaction process.The results showed that the DSA yield of 92.69%obtained by RPB was 5.35%higher than that by STR,indicating that RPB can significantly intensify the mass transfer in the liquid-solid phase sulfonation reaction process.展开更多
Taurine(2-amino-ethanesulfonic acid)is a naturally occurring amino sulfonic acid derived from cysteine and methionine metabolism.Its common name derives from the ox,as it was first isolated from the bile of an ox(Frog...Taurine(2-amino-ethanesulfonic acid)is a naturally occurring amino sulfonic acid derived from cysteine and methionine metabolism.Its common name derives from the ox,as it was first isolated from the bile of an ox(Froger et al.,2014).The molecular structure of taurine differs from that of amino acids by the presence of a sulfonic acid,instead of the more common carboxylic acid group in the structure of amino acids.展开更多
5-aminosalicylic acid(5-ASA) is drug of choice for the treatment of ulcerative colitis(UC). In this study, the efficacy of topical versus oral 5-ASA for the treatment of UC was examined as well as the action mecha...5-aminosalicylic acid(5-ASA) is drug of choice for the treatment of ulcerative colitis(UC). In this study, the efficacy of topical versus oral 5-ASA for the treatment of UC was examined as well as the action mechanism of this medication. A flexible tube was inserted into the rat cecum to establish a topical administration model of 2,4,6-trinitrobenzene sulfonic acid(TNBS)-induced UC. A total of 60 rats were divided into sham operation group(receiving an enema of 0.9% saline solution instead of the TNBS solution via the tube), model group, topical 5-ASA group, oral Etiasa group(a release agent of mesalazine used as positive control) and oral 5-ASA group(n=12 each). Different treatments were administered 1 day after UC induction. The normal saline(2 mL) was instilled twice a day through the tube in the sham operation group and model group. 5-ASA was given via the tube in the topical 5-ASA group(7.5 g/L, twice per day, 100 mg/kg), and rats in the oral Etiasa group and oral 5-ASA group intragastrically received Etiasa(7.5 g/L, twice per day, 100 mg/kg) and 5-ASA(7.5 g/L, twice per day, 100 mg/kg), respectively. The body weight was recorded every day. After 7 days of treatment, blood samples were drawn from the heart to harvest the sera. Colonic tissues were separated and prepared for pathological and related molecular biological examinations. The concentrations of 5-ASA were detected at different time points in the colonic tissues, feces and sera in different groups by using the high pressure liquid chromatography(HPLC). The results showed that the symptoms of acute UC, including bloody diarrhea and weight loss, were significantly improved in topical 5-ASA-treated rats. The colonic mucosal damage, both macroscopical and histological, was significantly relieved and the myeloperoxidase activity was markedly decreased in rats topically treated with 5-ASA compared with those treated with oral 5-ASA or Etiasa. The mRNA and protein expression of IL-1β, IL-6, and TNF-α was down-regulated in the colonic tissue of rats topically treated with 5-ASA, significantly lower than those from rats treated with oral 5-ASA or Etiasa. The concentrations of 5-ASA in the colonic tissue were significantly higher in the topical 5-ASA group than in the oral 5-ASA and oral Etiasa groups. It was concluded that the topical administration of 5-ASA can effectively increase the concentration of 5-ASA in the colonic tissue, decrease the expression of proinflammatory cytokines, alleviate the colonic pathological damage and improve the symptoms of TNBS-induced acute UC in rats.展开更多
The BST oilfield in the northwestern Taklamakan Desert is a fractured carbonate reservoir,but issues of water breakthrough are becoming increasingly severe with the development of water flooding.Unfortunately,the high...The BST oilfield in the northwestern Taklamakan Desert is a fractured carbonate reservoir,but issues of water breakthrough are becoming increasingly severe with the development of water flooding.Unfortunately,the high-temperature and high-salt conditions(130°C,71695 mg/L)of the BST oilfield pose challenges for the development of plugging agents.In this study,the effects of 2-acrylamido-2-methylpropane sulfonic acid(AMPS)content on AM/AMPS copolymers and gels were studied through viscosity measurements,nuclear magnetic resonance(NMR),and cryo-scanning electron microscope(Cryo-SEM).Moreover,the AMPS stabilization mechanism of the polymers and gels was explained.Heatresistant and salt-tolerant gel systems were developed,and their gelation properties,thermal stability,injection capacity,and plugging ability were evaluated.Experimental results showed inconsistencies between the effects of AMPS content on the polymers and gels.For the polymers,the thermal stability increased with increased AMPS content in the polymer.However,excessive AMPS content resulted in poor gelation and low strength.The developed gel systems with S30 polymer(AMPS content is approximately 26%)exhibited excellent thermal stability,controllable gelation time,good injection capacity,and plugging ability.The field application results indicated that most production wells had a positive response,with reduced water-cut and increased daily oil production.展开更多
The title compound, [Ni(tssb)(2,2-bipy)2].5(H2O) 1 (tssbH2 =2-[(E)-(2-oxido- phenyl)methyleneamino]ethanesulfonato, 2,2-bipy = 2,2'-bipyridinyl), belongs to orthorhombic, space group Pbcn with a = 20.3983...The title compound, [Ni(tssb)(2,2-bipy)2].5(H2O) 1 (tssbH2 =2-[(E)-(2-oxido- phenyl)methyleneamino]ethanesulfonato, 2,2-bipy = 2,2'-bipyridinyl), belongs to orthorhombic, space group Pbcn with a = 20.3983(18), b = 17.6929(15), c = 17.0897(15) nm, V= 6167.8(9) nm^3, Mr= 688.38, Z = 8, De = 1.481 g.cm^-3, F(000) = 2880,μ = 0.758 mm-1 and S =1.099. Each NiIr atom is six-coordinated by one N and one O atoms from one tssb^2- anion and four N atoms from two 2,2-bipy ligands to give a distorted octahedral geometry. Noticeably, there exists a rare octa-mem- bered water ring which presents a 1D chain by sulfonic group.展开更多
Chemical functionalization of chitosan biopolymer and chitosan-magnetite nanocomposite was performed with sulfonic acid functional groups to achieve new solid acid materials.The sulfonic acid functional groups were cr...Chemical functionalization of chitosan biopolymer and chitosan-magnetite nanocomposite was performed with sulfonic acid functional groups to achieve new solid acid materials.The sulfonic acid functional groups were created through the ring opening nucleophilic reaction of amine groups of chitosan with 1,4-butane sultone.Fourier transform infrared spectroscopy(FT-IR)and X-ray photoelectron spectroscopies(XPS)verified the successful sulfonic acid functionalization of chitosan.The obtained sulfonic acid functionalized chitosan-magnetite nanocomposite showed superparamagnetic properties according to the vibrating sample magnetometry analysis and exhibited magnetic separation feature from dispersed mixtures.Nitrogen adsorption-desorption analysis indicated the increase in surface area after formation of chitosan-magnetite nanocomposite and functionalization with sulfonic acid.Both of the prepared solid acids exhibited high catalytic activities in the acid-catalyzed acetic acid esterification with n-butanol and benzaldehyde acetalization with ethylene glycol as model reactions.Furthermore,they can be reused several times without considerable loss of their activities.展开更多
A main-chain liquid crystalline ionomer(MLCI) containing sulfonic group was synthesized by an interfacial condensation reaction.The MLCI was blended with polybutylene terephthalate(PBT) and polypropylene(PP).MLC...A main-chain liquid crystalline ionomer(MLCI) containing sulfonic group was synthesized by an interfacial condensation reaction.The MLCI was blended with polybutylene terephthalate(PBT) and polypropylene(PP).MLCI interacted with both the dispersed(PP) phase and the matrix(PBT) phase to modify the interfacial interaction of PBT and PP.Differential scanning calorimetry(DSC),scanning electron microscopy(SEM) and FTIR imaging system analysis demonstrated the significance of interfacial interaction in the polymer blends.MLCI brought about good adhesion at the interfacial,which reduced the disperse phase size and enabled a fine PP phase at matrix.The mechanical properties of the ternary blends were improved when a proper amount of MLCI was added.This was attributed to enhanced adhesion at the interface,which invoked better mechanical properties in the blends.展开更多
The adsorption equilibrium isotherms of three aromatic sulfonic acid compounds, 2-naphthalenesulfonic acid, p-toluenesulfonic acid and p-chlorobenzenesulfonic acid, from aqueous solutions by macroporous weak base anio...The adsorption equilibrium isotherms of three aromatic sulfonic acid compounds, 2-naphthalenesulfonic acid, p-toluenesulfonic acid and p-chlorobenzenesulfonic acid, from aqueous solutions by macroporous weak base anion exchanger within the temperature range of 293 K-313 K were obtained. Several isotherm equations were correlated with the equilibrium data, and the experimental data was found to fit the three-parameter Redlich-Peterson equation best within the entire range of concentrations. The study showed that the hydrophobicity of solute has distinct influence on adsorption capacity of the anion exchanger for the aromatic sulfonic acid. Moreover, estimations of the isosteric enthalpy, free energy, and entropy change of adsorption were also reported. The positive isosteric enthalpy and entropy change for adsorption indicate an endothermic and entropy driven process in the present study.展开更多
The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to ...The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to shorter wavelength when polyaniline was doped with CSAH in N methyl 2 pyrrolidione (NMP) solvent, while the red shift of polaron band was observed when it was in N, N dimethylformamide (DMF). It indicates that the influence of different processing solvents on the doping property of polyaniline is greatly different. N methyl 2 pyrrolidione is a good solvent for polyaniline, polyaniline chain is unfolded in it. The interaction of NMP with CSAH is so strong that the resulting product is apt to dedoping, while the solubility of polyaniline in DMF is relatively low and polyaniline chain is in partly folded state. Thus the doping reaction is kinetically disadvantageous but thermodynamically advantageous.展开更多
The degradation mechanism of photocrosslinking products formed by cyclized polyisoprene-diazide system under the influence of the different alkyl benzene sulfonic acids was studied. The effects of alkyl chain length a...The degradation mechanism of photocrosslinking products formed by cyclized polyisoprene-diazide system under the influence of the different alkyl benzene sulfonic acids was studied. The effects of alkyl chain length and the concentration of alkyl benzene sulfonic acids on the rate of degradation reaction were discussed. It was found that in the initial stage of degradation, the cyclicity ratio and the average fused ring number did not change considerably, but the percentage of uncyclized parts content varied significantly. The suitable mechanism was supposed.展开更多
The preparation of sterically stabilized poly(3, 4-ethylenedioxythiophene)(PEDOT) colloidal dispersions doped with different sulfonic acids is described. Three different sulfonic acids, i.e., p-toluenesulfonic aci...The preparation of sterically stabilized poly(3, 4-ethylenedioxythiophene)(PEDOT) colloidal dispersions doped with different sulfonic acids is described. Three different sulfonic acids, i.e., p-toluenesulfonic acid, β-naphthalenesulfonic acid and D-camphor-10-sulfonic acid are used, facilitating the preparation of sterically stable PEDOT colloidal particles. The influences of the dopants and concentration of polymeric stabilizer on the yields, morphologies and electrical properties of the resultant colloidal particles were investigated. The colloidal particles with the size ranging from 172 to 334 nm have been obtained in good yields. The compressed pellet conductivity was as high as 4.5 Scm^-1展开更多
Poly (m-aminobenzene sulfonic acid, m-ABSA) films were electrochemically prepared by cyclic voltammetry (CV) in 0.1 mol L–1 KCl solution. The dopamine (DA) selectivity of polymeric electrodes prepared at the differen...Poly (m-aminobenzene sulfonic acid, m-ABSA) films were electrochemically prepared by cyclic voltammetry (CV) in 0.1 mol L–1 KCl solution. The dopamine (DA) selectivity of polymeric electrodes prepared at the different thicknesses was examined in the presence of ascorbic acid (AA). The results showed that the modified electrode showed an excellent electrocatalytical effect towards oxidation of dopamine (DA) and ascorbic acid (AA). Electrostatic interaction between the negatively charged poly(m-ABSA) film and either cationic DA species or anionic AA species favorably contributed to the redox response of DA and AA. Moreover, the regular and repetitive responses for dopamine were obtained even in the presence of the some interfering substances such as ascorbic acid, NaCl, NaClO4, Na2SO4 ,NaNO3 and KCl.展开更多
The effect of additive—dodecylbenzene sulfonic acid(DBSA)—on residue hydrotreating was studied in the au toclave. The results showed that the additive improved stabilization of the colloid system of residue, which c...The effect of additive—dodecylbenzene sulfonic acid(DBSA)—on residue hydrotreating was studied in the au toclave. The results showed that the additive improved stabilization of the colloid system of residue, which could delay th aggregation and coke formation from asphaltenes on the catalyst, and make heavy components transformed into light oi The residue conversion in the presence of this additive increased by 1.94%, and the yield of light oil increased by 1.53%when the reaction time was 90 min. The surface properties of the catalyst in the presence of this additive were better tha that of the blank test within a very short time(30 min) and deteriorated rapidly after a longer reaction time due to highe conversion and coke deposition. Compared with the blank test, the case using the said additive had shown that the structur of hydrotreated asphaltene units was smaller and the condensation degrees were higher. The test results indicated that th additive could improve the hydrotreating reactivity of residue via permeation and depolymerization, the heavier componen could be transformed into light oil more easily, and the light oil yield and residue conversion were higher for the case usin the said additive in residue hydrotreating process.展开更多
Two series of interpenetrating sulfonic acid resins (ISAR), 10×n and n×10, were prepared by means of the wet method, and the physicochemical, thermodynamic and kinetic properties of the ISAR were measured. T...Two series of interpenetrating sulfonic acid resins (ISAR), 10×n and n×10, were prepared by means of the wet method, and the physicochemical, thermodynamic and kinetic properties of the ISAR were measured. The results show: 10×n resins exhibit better properties than n×10 ones, mainly in higher apparent degree of crosslinking and larger conformational entropy effect, among which, 10×1 resin exhibits the best thermodynamic and kinetic properties. In the DTA graphs of n×10 resins, there are two T_g and two T_(ox), but in those of 10×n, only one T_g and one T_(ox). This result well supports the conclusion that 10×n resins have much better interpenetrating structural aspects.展开更多
Functionalized PS/SiO_2 composite nanoparticles bearing sulfonic groups on the surface were successfully synthesized via emulsion copolymerization using a polymerizable emulsifierαolefin solfonate(AOS).As demonstrate...Functionalized PS/SiO_2 composite nanoparticles bearing sulfonic groups on the surface were successfully synthesized via emulsion copolymerization using a polymerizable emulsifierαolefin solfonate(AOS).As demonstrated by transmission electron microscopy and atomic force microscopy,well-defined core-shell PS/SiO_2 composite nanoparticles with a diameter of 50 nm were obtained.Sulfonic groups introduced onto the surface of the composite nanoparticles were quantified by FTIR,and can be controlled to some exten...展开更多
Dodecyl benzenesulfonic acid(DBSA)surfactant was used in the present study to find the effect of concentrationon its electrical conductance in solution from 293-323 K above and below the critical micelle concentration...Dodecyl benzenesulfonic acid(DBSA)surfactant was used in the present study to find the effect of concentrationon its electrical conductance in solution from 293-323 K above and below the critical micelle concentration(CMC).Themicellization parameters i.e.degree of counter ion binding(β),aggregation number(n)and number of counter ion micelle(m)were measured.The interaction of DBSA with polyvinylpyrrolidone(PVP)was also studied at 293 K throughconductance and surface tension measure ments.A number of important parameters i.e.critical aggregation concentration(CAC),Gibb's free energy(△G)and binding ratio(R)were determined and the effect of NaCl on the CAC and polymersaturation point(PSP)was also investigated.展开更多
Hydroxyquinoline 5 sulfonic acid, covalently bound to filter cellulose, was used for preconcentrating trace rare earth element(REE) ions from complex matrices and matrix separation, respectively. Multi REE ions wer...Hydroxyquinoline 5 sulfonic acid, covalently bound to filter cellulose, was used for preconcentrating trace rare earth element(REE) ions from complex matrices and matrix separation, respectively. Multi REE ions were preconcentrated on the column filled with 8 hydroxyquinoline 5 sulfonic acid cellulose filter and analysed by ICP AES after being eluted with dilute HNO 3. In the given pH range, alkali and alkaline earth metal ions can be separated as matrix elements; a high concentration factor is obtained and the eluates can be measured without interference. The usefulness of the method is shown by the control analyses of standard reference materials. [WT5FZ]展开更多
The terpolymer of itaconic acid, acrylamide and 2-acrylamido-2-methyl-1-propane sulfonic acid was synthesized through the free-radical polymerization. The IR spectra confirmed that there was no olefinic band, while th...The terpolymer of itaconic acid, acrylamide and 2-acrylamido-2-methyl-1-propane sulfonic acid was synthesized through the free-radical polymerization. The IR spectra confirmed that there was no olefinic band, while the TGA results revealed that the terpolymer was of high thermal stability.展开更多
A new fluorescent reagent, 7 (8 hydroxy 3, 6 disulfonaphthylazo) 8 hydroxyquinoline 5 sulfonic acid (HDNHQ) for the determination of magnesium has been developed. It reacted with magnesium to form a 1∶1 fluor...A new fluorescent reagent, 7 (8 hydroxy 3, 6 disulfonaphthylazo) 8 hydroxyquinoline 5 sulfonic acid (HDNHQ) for the determination of magnesium has been developed. It reacted with magnesium to form a 1∶1 fluorescent complex with λ ex / λ em =356/495 nm immediately at room temperature in ammonia ammonium chloride buffer (pH 10.7). A linear relationship was obtained in the magnesium concentration range of 0 160 ng·mL -1 with the detection limit of 0.04 ng·mL -1 . The proposed method was simple, rapid and sensitive. It has been successfully applied to the determination of trace magnesium in blood serum with recoveries of 103.75% and 98.16%, respectively.展开更多
Polypyrrole-polystyrene sulfonic acid(PPy-PSSA)composite films have been electrosynthesized in an aqueoussolution of PSSA.The electro-active films exhibit cation exchange during the redox process.Infrared,Raman and en...Polypyrrole-polystyrene sulfonic acid(PPy-PSSA)composite films have been electrosynthesized in an aqueoussolution of PSSA.The electro-active films exhibit cation exchange during the redox process.Infrared,Raman and energy-dispersive spectroscopic results demonstrated that the polyanion of PSS^- is co-deposited into the PPy matrix and couldn't bestripped fiom the film extensively by dedoping.The doping level together with dipolaron content of the PPy-PSSAcomposite film increases during electrochemical polymerization process.SEM images revealed that the composite film hassmooth and compact morphology and AFM pictures suggested that PPy chains are possibly grown perpendicular to theelectrode surface.TGA tests indicated that the composite films has much better thermal stability than that of pure PPy.Furthermore,electrochemical studies showed that the relaxation process at certain holding potential has great effect on theshape of the cyclic voltammetric curves of PPy-PSSA composite film.The composite film exhibits cation and anionexchange during the redox process after undergoing the relaxation step.It is more difficult for divalent anion to enter thepolymer matrix than a univalent ion,and a large cation such as(CH_3CH_2CH_2CH_2)_4N^+ cannot be involved in the ionexchange process.展开更多
基金financially supported by the National Key Research and Development Program of China(2016YFB0301500)the National Natural Science Foundation of China(21878009)。
文摘The work herein employed a rotating packed bed(RPB)to intensify the sulfonation process of 1,4-diaminoanthraquinone leuco(DL)in an attempt to improve the yield of the product 1,4-diaminoanthra quinone-2-sulfonic acid(DSA).First,the effects of operating conditions in a stirred tank reactor(STR),including stirring speed,chlorosulfonic acid/DL molar ratio(η),solvent/DL mass ratio(ζ),reaction temperature and dropping speed of chlorosulfonic acid,on the yield of DSA were investigated.The yield of DSA can reach 87.34%under the optimal operating conditions:stirring speed of 500 r·min^(-1),ηof 4.5,ζof 7,reaction temperature of 150℃,dropping speed of 0.61 ml·min^(-1).In addition,the kinetics of the sulfonation process via the shrinking core model revealed that the reaction is controlled by diffusion via a product layer under the reaction temperature of 140℃.Furthermore,the RPB was employed to intensify the mass transfer between liquid and solid phases during the sulfonation reaction process.The results showed that the DSA yield of 92.69%obtained by RPB was 5.35%higher than that by STR,indicating that RPB can significantly intensify the mass transfer in the liquid-solid phase sulfonation reaction process.
基金supported by Instituto de Salud CarlosⅢ(ISCⅢ):PI19/00203,co-funded by ERDF“A way to make Europe”to MPVP and DGA,RD16/0008/0026 co-funded by ERDF+3 种基金“A way to make Europe”to MPVP and RD21/0002/0014 financiado por la Unión Europea–Next Generation EUFundación Robles Chillida to DGAthe RHU LIGHT4DEAF[ANR-15-RHU-0001]IHU FORe SIGHT[ANR-18-IAHU-0001]to SP。
文摘Taurine(2-amino-ethanesulfonic acid)is a naturally occurring amino sulfonic acid derived from cysteine and methionine metabolism.Its common name derives from the ox,as it was first isolated from the bile of an ox(Froger et al.,2014).The molecular structure of taurine differs from that of amino acids by the presence of a sulfonic acid,instead of the more common carboxylic acid group in the structure of amino acids.
基金supported by grants from the National Natural Science Foundation of China(No.81072431)the Innova-tion Foundation of Huazhong University of Science and Tech-nology(No.2010MS027)
文摘5-aminosalicylic acid(5-ASA) is drug of choice for the treatment of ulcerative colitis(UC). In this study, the efficacy of topical versus oral 5-ASA for the treatment of UC was examined as well as the action mechanism of this medication. A flexible tube was inserted into the rat cecum to establish a topical administration model of 2,4,6-trinitrobenzene sulfonic acid(TNBS)-induced UC. A total of 60 rats were divided into sham operation group(receiving an enema of 0.9% saline solution instead of the TNBS solution via the tube), model group, topical 5-ASA group, oral Etiasa group(a release agent of mesalazine used as positive control) and oral 5-ASA group(n=12 each). Different treatments were administered 1 day after UC induction. The normal saline(2 mL) was instilled twice a day through the tube in the sham operation group and model group. 5-ASA was given via the tube in the topical 5-ASA group(7.5 g/L, twice per day, 100 mg/kg), and rats in the oral Etiasa group and oral 5-ASA group intragastrically received Etiasa(7.5 g/L, twice per day, 100 mg/kg) and 5-ASA(7.5 g/L, twice per day, 100 mg/kg), respectively. The body weight was recorded every day. After 7 days of treatment, blood samples were drawn from the heart to harvest the sera. Colonic tissues were separated and prepared for pathological and related molecular biological examinations. The concentrations of 5-ASA were detected at different time points in the colonic tissues, feces and sera in different groups by using the high pressure liquid chromatography(HPLC). The results showed that the symptoms of acute UC, including bloody diarrhea and weight loss, were significantly improved in topical 5-ASA-treated rats. The colonic mucosal damage, both macroscopical and histological, was significantly relieved and the myeloperoxidase activity was markedly decreased in rats topically treated with 5-ASA compared with those treated with oral 5-ASA or Etiasa. The mRNA and protein expression of IL-1β, IL-6, and TNF-α was down-regulated in the colonic tissue of rats topically treated with 5-ASA, significantly lower than those from rats treated with oral 5-ASA or Etiasa. The concentrations of 5-ASA in the colonic tissue were significantly higher in the topical 5-ASA group than in the oral 5-ASA and oral Etiasa groups. It was concluded that the topical administration of 5-ASA can effectively increase the concentration of 5-ASA in the colonic tissue, decrease the expression of proinflammatory cytokines, alleviate the colonic pathological damage and improve the symptoms of TNBS-induced acute UC in rats.
基金Financial support from the Major Scientific and Technological Project of CNPC under grant number ZD2019-183-007Sinopec Northwest Company of China for the financial support(34400007-17-ZC06070095)
文摘The BST oilfield in the northwestern Taklamakan Desert is a fractured carbonate reservoir,but issues of water breakthrough are becoming increasingly severe with the development of water flooding.Unfortunately,the high-temperature and high-salt conditions(130°C,71695 mg/L)of the BST oilfield pose challenges for the development of plugging agents.In this study,the effects of 2-acrylamido-2-methylpropane sulfonic acid(AMPS)content on AM/AMPS copolymers and gels were studied through viscosity measurements,nuclear magnetic resonance(NMR),and cryo-scanning electron microscope(Cryo-SEM).Moreover,the AMPS stabilization mechanism of the polymers and gels was explained.Heatresistant and salt-tolerant gel systems were developed,and their gelation properties,thermal stability,injection capacity,and plugging ability were evaluated.Experimental results showed inconsistencies between the effects of AMPS content on the polymers and gels.For the polymers,the thermal stability increased with increased AMPS content in the polymer.However,excessive AMPS content resulted in poor gelation and low strength.The developed gel systems with S30 polymer(AMPS content is approximately 26%)exhibited excellent thermal stability,controllable gelation time,good injection capacity,and plugging ability.The field application results indicated that most production wells had a positive response,with reduced water-cut and increased daily oil production.
基金Supported by the Key Laboratory of Non-ferrous Metal Materials and New Processing TechnologyMinistry of Education and the State Key Laboratory of Coordination Chemistry
文摘The title compound, [Ni(tssb)(2,2-bipy)2].5(H2O) 1 (tssbH2 =2-[(E)-(2-oxido- phenyl)methyleneamino]ethanesulfonato, 2,2-bipy = 2,2'-bipyridinyl), belongs to orthorhombic, space group Pbcn with a = 20.3983(18), b = 17.6929(15), c = 17.0897(15) nm, V= 6167.8(9) nm^3, Mr= 688.38, Z = 8, De = 1.481 g.cm^-3, F(000) = 2880,μ = 0.758 mm-1 and S =1.099. Each NiIr atom is six-coordinated by one N and one O atoms from one tssb^2- anion and four N atoms from two 2,2-bipy ligands to give a distorted octahedral geometry. Noticeably, there exists a rare octa-mem- bered water ring which presents a 1D chain by sulfonic group.
文摘Chemical functionalization of chitosan biopolymer and chitosan-magnetite nanocomposite was performed with sulfonic acid functional groups to achieve new solid acid materials.The sulfonic acid functional groups were created through the ring opening nucleophilic reaction of amine groups of chitosan with 1,4-butane sultone.Fourier transform infrared spectroscopy(FT-IR)and X-ray photoelectron spectroscopies(XPS)verified the successful sulfonic acid functionalization of chitosan.The obtained sulfonic acid functionalized chitosan-magnetite nanocomposite showed superparamagnetic properties according to the vibrating sample magnetometry analysis and exhibited magnetic separation feature from dispersed mixtures.Nitrogen adsorption-desorption analysis indicated the increase in surface area after formation of chitosan-magnetite nanocomposite and functionalization with sulfonic acid.Both of the prepared solid acids exhibited high catalytic activities in the acid-catalyzed acetic acid esterification with n-butanol and benzaldehyde acetalization with ethylene glycol as model reactions.Furthermore,they can be reused several times without considerable loss of their activities.
基金Supported by the High-Tech Research and Development Program of China(No.2006AA02Z291)the National Natural Science Foundation of China(No.50673105)
文摘A main-chain liquid crystalline ionomer(MLCI) containing sulfonic group was synthesized by an interfacial condensation reaction.The MLCI was blended with polybutylene terephthalate(PBT) and polypropylene(PP).MLCI interacted with both the dispersed(PP) phase and the matrix(PBT) phase to modify the interfacial interaction of PBT and PP.Differential scanning calorimetry(DSC),scanning electron microscopy(SEM) and FTIR imaging system analysis demonstrated the significance of interfacial interaction in the polymer blends.MLCI brought about good adhesion at the interfacial,which reduced the disperse phase size and enabled a fine PP phase at matrix.The mechanical properties of the ternary blends were improved when a proper amount of MLCI was added.This was attributed to enhanced adhesion at the interface,which invoked better mechanical properties in the blends.
文摘The adsorption equilibrium isotherms of three aromatic sulfonic acid compounds, 2-naphthalenesulfonic acid, p-toluenesulfonic acid and p-chlorobenzenesulfonic acid, from aqueous solutions by macroporous weak base anion exchanger within the temperature range of 293 K-313 K were obtained. Several isotherm equations were correlated with the equilibrium data, and the experimental data was found to fit the three-parameter Redlich-Peterson equation best within the entire range of concentrations. The study showed that the hydrophobicity of solute has distinct influence on adsorption capacity of the anion exchanger for the aromatic sulfonic acid. Moreover, estimations of the isosteric enthalpy, free energy, and entropy change of adsorption were also reported. The positive isosteric enthalpy and entropy change for adsorption indicate an endothermic and entropy driven process in the present study.
文摘The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to shorter wavelength when polyaniline was doped with CSAH in N methyl 2 pyrrolidione (NMP) solvent, while the red shift of polaron band was observed when it was in N, N dimethylformamide (DMF). It indicates that the influence of different processing solvents on the doping property of polyaniline is greatly different. N methyl 2 pyrrolidione is a good solvent for polyaniline, polyaniline chain is unfolded in it. The interaction of NMP with CSAH is so strong that the resulting product is apt to dedoping, while the solubility of polyaniline in DMF is relatively low and polyaniline chain is in partly folded state. Thus the doping reaction is kinetically disadvantageous but thermodynamically advantageous.
文摘The degradation mechanism of photocrosslinking products formed by cyclized polyisoprene-diazide system under the influence of the different alkyl benzene sulfonic acids was studied. The effects of alkyl chain length and the concentration of alkyl benzene sulfonic acids on the rate of degradation reaction were discussed. It was found that in the initial stage of degradation, the cyclicity ratio and the average fused ring number did not change considerably, but the percentage of uncyclized parts content varied significantly. The suitable mechanism was supposed.
文摘The preparation of sterically stabilized poly(3, 4-ethylenedioxythiophene)(PEDOT) colloidal dispersions doped with different sulfonic acids is described. Three different sulfonic acids, i.e., p-toluenesulfonic acid, β-naphthalenesulfonic acid and D-camphor-10-sulfonic acid are used, facilitating the preparation of sterically stable PEDOT colloidal particles. The influences of the dopants and concentration of polymeric stabilizer on the yields, morphologies and electrical properties of the resultant colloidal particles were investigated. The colloidal particles with the size ranging from 172 to 334 nm have been obtained in good yields. The compressed pellet conductivity was as high as 4.5 Scm^-1
基金financially supported by the Research Fund Unit of Inonu University(Grant no APYB:2008/48).
文摘Poly (m-aminobenzene sulfonic acid, m-ABSA) films were electrochemically prepared by cyclic voltammetry (CV) in 0.1 mol L–1 KCl solution. The dopamine (DA) selectivity of polymeric electrodes prepared at the different thicknesses was examined in the presence of ascorbic acid (AA). The results showed that the modified electrode showed an excellent electrocatalytical effect towards oxidation of dopamine (DA) and ascorbic acid (AA). Electrostatic interaction between the negatively charged poly(m-ABSA) film and either cationic DA species or anionic AA species favorably contributed to the redox response of DA and AA. Moreover, the regular and repetitive responses for dopamine were obtained even in the presence of the some interfering substances such as ascorbic acid, NaCl, NaClO4, Na2SO4 ,NaNO3 and KCl.
基金the financial support provided by the National Natural Science Foundation of China (Grant No. 21376266)the Petro China Innovation Foundation (Grant No. 2011D-5006-0405)the Fundamental Research Funds for the Central Universities (Grant No. 27R1104049A)
文摘The effect of additive—dodecylbenzene sulfonic acid(DBSA)—on residue hydrotreating was studied in the au toclave. The results showed that the additive improved stabilization of the colloid system of residue, which could delay th aggregation and coke formation from asphaltenes on the catalyst, and make heavy components transformed into light oi The residue conversion in the presence of this additive increased by 1.94%, and the yield of light oil increased by 1.53%when the reaction time was 90 min. The surface properties of the catalyst in the presence of this additive were better tha that of the blank test within a very short time(30 min) and deteriorated rapidly after a longer reaction time due to highe conversion and coke deposition. Compared with the blank test, the case using the said additive had shown that the structur of hydrotreated asphaltene units was smaller and the condensation degrees were higher. The test results indicated that th additive could improve the hydrotreating reactivity of residue via permeation and depolymerization, the heavier componen could be transformed into light oil more easily, and the light oil yield and residue conversion were higher for the case usin the said additive in residue hydrotreating process.
文摘Two series of interpenetrating sulfonic acid resins (ISAR), 10×n and n×10, were prepared by means of the wet method, and the physicochemical, thermodynamic and kinetic properties of the ISAR were measured. The results show: 10×n resins exhibit better properties than n×10 ones, mainly in higher apparent degree of crosslinking and larger conformational entropy effect, among which, 10×1 resin exhibits the best thermodynamic and kinetic properties. In the DTA graphs of n×10 resins, there are two T_g and two T_(ox), but in those of 10×n, only one T_g and one T_(ox). This result well supports the conclusion that 10×n resins have much better interpenetrating structural aspects.
基金supported by the Hi-Tech Research and Development Program of China(863,No2006AA03Z562)
文摘Functionalized PS/SiO_2 composite nanoparticles bearing sulfonic groups on the surface were successfully synthesized via emulsion copolymerization using a polymerizable emulsifierαolefin solfonate(AOS).As demonstrated by transmission electron microscopy and atomic force microscopy,well-defined core-shell PS/SiO_2 composite nanoparticles with a diameter of 50 nm were obtained.Sulfonic groups introduced onto the surface of the composite nanoparticles were quantified by FTIR,and can be controlled to some exten...
文摘Dodecyl benzenesulfonic acid(DBSA)surfactant was used in the present study to find the effect of concentrationon its electrical conductance in solution from 293-323 K above and below the critical micelle concentration(CMC).Themicellization parameters i.e.degree of counter ion binding(β),aggregation number(n)and number of counter ion micelle(m)were measured.The interaction of DBSA with polyvinylpyrrolidone(PVP)was also studied at 293 K throughconductance and surface tension measure ments.A number of important parameters i.e.critical aggregation concentration(CAC),Gibb's free energy(△G)and binding ratio(R)were determined and the effect of NaCl on the CAC and polymersaturation point(PSP)was also investigated.
基金Supported by the National Natural Science Foundation of China
文摘Hydroxyquinoline 5 sulfonic acid, covalently bound to filter cellulose, was used for preconcentrating trace rare earth element(REE) ions from complex matrices and matrix separation, respectively. Multi REE ions were preconcentrated on the column filled with 8 hydroxyquinoline 5 sulfonic acid cellulose filter and analysed by ICP AES after being eluted with dilute HNO 3. In the given pH range, alkali and alkaline earth metal ions can be separated as matrix elements; a high concentration factor is obtained and the eluates can be measured without interference. The usefulness of the method is shown by the control analyses of standard reference materials. [WT5FZ]
文摘The terpolymer of itaconic acid, acrylamide and 2-acrylamido-2-methyl-1-propane sulfonic acid was synthesized through the free-radical polymerization. The IR spectra confirmed that there was no olefinic band, while the TGA results revealed that the terpolymer was of high thermal stability.
基金Supported by the Zi-Qiang Foundation of Wuhan U niversit
文摘A new fluorescent reagent, 7 (8 hydroxy 3, 6 disulfonaphthylazo) 8 hydroxyquinoline 5 sulfonic acid (HDNHQ) for the determination of magnesium has been developed. It reacted with magnesium to form a 1∶1 fluorescent complex with λ ex / λ em =356/495 nm immediately at room temperature in ammonia ammonium chloride buffer (pH 10.7). A linear relationship was obtained in the magnesium concentration range of 0 160 ng·mL -1 with the detection limit of 0.04 ng·mL -1 . The proposed method was simple, rapid and sensitive. It has been successfully applied to the determination of trace magnesium in blood serum with recoveries of 103.75% and 98.16%, respectively.
基金This work was supported by the National Natural Science Foundation of China(No.50225311,20374034,50133010).
文摘Polypyrrole-polystyrene sulfonic acid(PPy-PSSA)composite films have been electrosynthesized in an aqueoussolution of PSSA.The electro-active films exhibit cation exchange during the redox process.Infrared,Raman and energy-dispersive spectroscopic results demonstrated that the polyanion of PSS^- is co-deposited into the PPy matrix and couldn't bestripped fiom the film extensively by dedoping.The doping level together with dipolaron content of the PPy-PSSAcomposite film increases during electrochemical polymerization process.SEM images revealed that the composite film hassmooth and compact morphology and AFM pictures suggested that PPy chains are possibly grown perpendicular to theelectrode surface.TGA tests indicated that the composite films has much better thermal stability than that of pure PPy.Furthermore,electrochemical studies showed that the relaxation process at certain holding potential has great effect on theshape of the cyclic voltammetric curves of PPy-PSSA composite film.The composite film exhibits cation and anionexchange during the redox process after undergoing the relaxation step.It is more difficult for divalent anion to enter thepolymer matrix than a univalent ion,and a large cation such as(CH_3CH_2CH_2CH_2)_4N^+ cannot be involved in the ionexchange process.