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2009 Volume 26 Issue 8
2009, 26(8): 881-884
Abstract:
The anionic surfactant(1227) was used for the preparation of sodium base betonite(Na-Ben).The prepared 1227-Ben was characterized by FT-IR and XRD and used as subsidence-resistance for preparing 4%nicosulfuron oil-suspension.The effect of 1227-Ben on the physical stability of oil-suspension was examined.FT-IR spectra and XRD analysis results show that the organic agent was intercalated into the layer of montmorillonite.Subsidence-resistance test shows that the increase in 1227-Ben dosage could decrease oil separation rate and improve the viscosity,yield and suspension rate of oil-suspension,that is,1227-Ben could be used as a subsidence-resistance agent for the preparation of 4%nicosulfuron oil-suspension.
The anionic surfactant(1227) was used for the preparation of sodium base betonite(Na-Ben).The prepared 1227-Ben was characterized by FT-IR and XRD and used as subsidence-resistance for preparing 4%nicosulfuron oil-suspension.The effect of 1227-Ben on the physical stability of oil-suspension was examined.FT-IR spectra and XRD analysis results show that the organic agent was intercalated into the layer of montmorillonite.Subsidence-resistance test shows that the increase in 1227-Ben dosage could decrease oil separation rate and improve the viscosity,yield and suspension rate of oil-suspension,that is,1227-Ben could be used as a subsidence-resistance agent for the preparation of 4%nicosulfuron oil-suspension.
2009, 26(8): 885-889
Abstract:
Ten novel diheterocyclic thio-ether compounds containing 1,2,4-triazolo[1,5-a] pyrimidine and 1,2,4-triazole moieties were designed and synthesized with 2-mercapto-5,7-dimethyl-[1,2,4]triazolo[I,5-a] pyrimidine as starting material.All the compounds obtained were comfired by MS and 1H NMR.Preliminary biological activity test indicates most of compounds 6 display good activity against C.beticola.Especially,compounds 6b,6e,6f,6g and 6h can reach grade A(≥90%) at a concentration of 50 μg/L.
Ten novel diheterocyclic thio-ether compounds containing 1,2,4-triazolo[1,5-a] pyrimidine and 1,2,4-triazole moieties were designed and synthesized with 2-mercapto-5,7-dimethyl-[1,2,4]triazolo[I,5-a] pyrimidine as starting material.All the compounds obtained were comfired by MS and 1H NMR.Preliminary biological activity test indicates most of compounds 6 display good activity against C.beticola.Especially,compounds 6b,6e,6f,6g and 6h can reach grade A(≥90%) at a concentration of 50 μg/L.
2009, 26(8): 890-893
Abstract:
7-Phenylacetamido-3-pyridiniummethylcephem-4-carboxylic acid p-methoxybenzyl ester was prepared by the reaction of pyridine with 7-phenylacetamido-3-chloridecephem-4-carboxylic acid p-metho-xybenzyl ester iodide.The reaction process was inspected by HPLC in dichloromethane,acetone,tetrahydrofuran,the mixture of ethyl acetate and DMF.It was determined that the nucleophilic substitution reaction was a 2nd order reaction.In a given solvent the rate of the reaction perfectly obeyed Arrhenius's equation within the experimental temperature of 25 ℃ and 35 ℃.The activation energy and the preexponential factor were obtained,and the solvent effects were discussed.The activity order of the nucleophilicity in different solvents is as follows:acetone> tetrahydrofuran> the mixture of ethyl acetate and DMF> dichloromethane.
7-Phenylacetamido-3-pyridiniummethylcephem-4-carboxylic acid p-methoxybenzyl ester was prepared by the reaction of pyridine with 7-phenylacetamido-3-chloridecephem-4-carboxylic acid p-metho-xybenzyl ester iodide.The reaction process was inspected by HPLC in dichloromethane,acetone,tetrahydrofuran,the mixture of ethyl acetate and DMF.It was determined that the nucleophilic substitution reaction was a 2nd order reaction.In a given solvent the rate of the reaction perfectly obeyed Arrhenius's equation within the experimental temperature of 25 ℃ and 35 ℃.The activation energy and the preexponential factor were obtained,and the solvent effects were discussed.The activity order of the nucleophilicity in different solvents is as follows:acetone> tetrahydrofuran> the mixture of ethyl acetate and DMF> dichloromethane.
2009, 26(8): 894-898
Abstract:
2-Amino-5-(2-phenyl-1,2,3-triazol-4-yl)-1,3,4-thiodiazole(1) was prepared by the reaction of 2-phenyl-1,2,3-triazole-4-carboxylic acid with aminothiourea in the presence of phosphorus oxychloride.Then a series of N-[5-(2-phenyl-1,2,3-triazol-4-yl)-1,3,4-thiodiazol-2-yl]-N'-aroylthioureas was synthesized by the reaction of compound 1 with aroyl isothiocyanates by means of ultrasonic radiation method and ordinary method.The reaction time for the first method was about 12.5% that of the second one,and the yield was increased by 4%~17%.The side products were at the same time reduced.The structures of these compounds were confirmed by elemental analysis,MS,IR and 1H NMR spectroscopies.
2-Amino-5-(2-phenyl-1,2,3-triazol-4-yl)-1,3,4-thiodiazole(1) was prepared by the reaction of 2-phenyl-1,2,3-triazole-4-carboxylic acid with aminothiourea in the presence of phosphorus oxychloride.Then a series of N-[5-(2-phenyl-1,2,3-triazol-4-yl)-1,3,4-thiodiazol-2-yl]-N'-aroylthioureas was synthesized by the reaction of compound 1 with aroyl isothiocyanates by means of ultrasonic radiation method and ordinary method.The reaction time for the first method was about 12.5% that of the second one,and the yield was increased by 4%~17%.The side products were at the same time reduced.The structures of these compounds were confirmed by elemental analysis,MS,IR and 1H NMR spectroscopies.
2009, 26(8): 899-904
Abstract:
The Diels-Alder reactions between furan derivatives and dimethylacetyl enedecarboxylate were examined in ionic liquids [Bmim] Tf2N,[Bmim] PF6,and [Bmim] BF4,and it was found that the lower the polarity of the furan derivatives,the better the reactivity.The high yield(53%) of Diels-Alder reaction of alkylthiofuran with alkylacetylenedicarboxylate was observed when [Bmim] PF6 was used.Furthermore,it was observed that a higher reactivity was achieved when the reaction was conducted on the surface of silica gel coated with ionic liquid,and the silica gel supported ionic liquid was recycled three times without any significant decrease in chemical yield.
The Diels-Alder reactions between furan derivatives and dimethylacetyl enedecarboxylate were examined in ionic liquids [Bmim] Tf2N,[Bmim] PF6,and [Bmim] BF4,and it was found that the lower the polarity of the furan derivatives,the better the reactivity.The high yield(53%) of Diels-Alder reaction of alkylthiofuran with alkylacetylenedicarboxylate was observed when [Bmim] PF6 was used.Furthermore,it was observed that a higher reactivity was achieved when the reaction was conducted on the surface of silica gel coated with ionic liquid,and the silica gel supported ionic liquid was recycled three times without any significant decrease in chemical yield.
2009, 26(8): 905-908
Abstract:
A novel ionic liquid(IL) caprolactam-trifluoromethanesulfonic acid([CP]OTf) was prepared with trifluoromethanesulfonic acid and caprolactam as raw materials.The structure of the IL was characterized by 1H NMR and FTIR,and was used as the catalyst and solvent in the nitration of toluene.The effects of the amount of catalyst,reaction temperature,reaction time,concentration of nitric acid and catalyst recycling on the yield and para-selectivity for the nitration of toluene were investigated with the aid of gas chromatography.The results show that when the nitration temperature was 55 ℃,the reaction time was 6 h,the molar ratio of toluene to 95% nitric acid was 1:1,the amount of catalyst was 15% of the molar amount of toluene,the ortho-para isomer ratio reached 1.12,far below 1.67 by using sulfuric acid,and gave a product yield of 78.41%.IL([CP]OTf) showed high regioselectivity and catalytic activity.The catalyst could be reutilized up to five times with little decrease in activity and regioselectivity.
A novel ionic liquid(IL) caprolactam-trifluoromethanesulfonic acid([CP]OTf) was prepared with trifluoromethanesulfonic acid and caprolactam as raw materials.The structure of the IL was characterized by 1H NMR and FTIR,and was used as the catalyst and solvent in the nitration of toluene.The effects of the amount of catalyst,reaction temperature,reaction time,concentration of nitric acid and catalyst recycling on the yield and para-selectivity for the nitration of toluene were investigated with the aid of gas chromatography.The results show that when the nitration temperature was 55 ℃,the reaction time was 6 h,the molar ratio of toluene to 95% nitric acid was 1:1,the amount of catalyst was 15% of the molar amount of toluene,the ortho-para isomer ratio reached 1.12,far below 1.67 by using sulfuric acid,and gave a product yield of 78.41%.IL([CP]OTf) showed high regioselectivity and catalytic activity.The catalyst could be reutilized up to five times with little decrease in activity and regioselectivity.
2009, 26(8): 909-912
Abstract:
A novel diselenide porphyrin dimmer was synthesized from 5-(4-hydroxylphenyl)-10,15,20-triphenyl porphyrin and powder selenium.The structure of the porphyrin was confirmed by 1H NMR,IR,UV-Vis,and HR-MS.The interaction between the porphyrin and bovine serum albumin(BSA) was investigated by means of fluorescence spectroscopy,and the binding constant Ksv was calculated to be 3.35×104 L/mol.The results show that the obtained porphyrin has a powerful ability of quenching the intrinsic fluorescence of BSA.
A novel diselenide porphyrin dimmer was synthesized from 5-(4-hydroxylphenyl)-10,15,20-triphenyl porphyrin and powder selenium.The structure of the porphyrin was confirmed by 1H NMR,IR,UV-Vis,and HR-MS.The interaction between the porphyrin and bovine serum albumin(BSA) was investigated by means of fluorescence spectroscopy,and the binding constant Ksv was calculated to be 3.35×104 L/mol.The results show that the obtained porphyrin has a powerful ability of quenching the intrinsic fluorescence of BSA.
2009, 26(8): 913-917
Abstract:
Three complexes of europium(Ⅲ) with Taurine-salicylaldehyde Schiff base([(Eu(TSal)L(NO3)]·2H2O,TSal:Taurine-salicylaldehyde Schiff base,L1:1,10-phenanthroline,L2:2-aminopyrimidine,L3:2,2'-bipyridine)have been synthesized and characterized.The interaction mode between the complexes and calf thymus DNA has been investigated by means of fluorescence spectroscopy and viscosity measurement.The results show that all the complexes can remarkably quench the emission intensity of the EB-DNA system.With increasing the concentration of the complexes,the ability of their binding to DNA is more prominent under the experimental conditions.All the experimental results indicate that the interaction of the complexes with calf thymus DNA is an intercalation mode.The sequence of intercalating ability of the complexes is [Eu(TSal)L1(NO3)]·2H2O> [Eu(TSal)L3(NO3)]·2H2O> [Eu(TSal)L2(NO3)]·2H2O.
Three complexes of europium(Ⅲ) with Taurine-salicylaldehyde Schiff base([(Eu(TSal)L(NO3)]·2H2O,TSal:Taurine-salicylaldehyde Schiff base,L1:1,10-phenanthroline,L2:2-aminopyrimidine,L3:2,2'-bipyridine)have been synthesized and characterized.The interaction mode between the complexes and calf thymus DNA has been investigated by means of fluorescence spectroscopy and viscosity measurement.The results show that all the complexes can remarkably quench the emission intensity of the EB-DNA system.With increasing the concentration of the complexes,the ability of their binding to DNA is more prominent under the experimental conditions.All the experimental results indicate that the interaction of the complexes with calf thymus DNA is an intercalation mode.The sequence of intercalating ability of the complexes is [Eu(TSal)L1(NO3)]·2H2O> [Eu(TSal)L3(NO3)]·2H2O> [Eu(TSal)L2(NO3)]·2H2O.
Spectroscopic Studies on the Interaction between Diammonium Glycyrrhizinate and Bovine Serum Albumin
2009, 26(8): 918-922
Abstract:
The interaction between diammonium glycyrrhizinate(DG) and bovine serum albumin(BSA) was studied in physicological solution by spectroscopic methods including fluorescence spectrometry and UV-Visible absorption spectrometry.Synchronous fluorescence and three-dimensional fluorescence spectra were used to investigate the conformational change of BSA due to the addition of DG.Fluorescence titration reveals that the flurescence intensity of BSA at 348 nm was quenched when DG was added.The dynamic quenching existed between DG and BSA according to the flurescence quenching data at different temperatures and the UV differential spectra.According to Frster theory of non-radiation energy transfer,the nearest distance(r=2.28 nm) and transfer efficiency of energy(E=0.05) between donor(BSA) and acceptor(DG) were determined.The effects of metal ions on the system were studied at room temperature.
The interaction between diammonium glycyrrhizinate(DG) and bovine serum albumin(BSA) was studied in physicological solution by spectroscopic methods including fluorescence spectrometry and UV-Visible absorption spectrometry.Synchronous fluorescence and three-dimensional fluorescence spectra were used to investigate the conformational change of BSA due to the addition of DG.Fluorescence titration reveals that the flurescence intensity of BSA at 348 nm was quenched when DG was added.The dynamic quenching existed between DG and BSA according to the flurescence quenching data at different temperatures and the UV differential spectra.According to Frster theory of non-radiation energy transfer,the nearest distance(r=2.28 nm) and transfer efficiency of energy(E=0.05) between donor(BSA) and acceptor(DG) were determined.The effects of metal ions on the system were studied at room temperature.
2009, 26(8): 923-928
Abstract:
Polymerizations of 5-norbornene-2-yl-acetate in toluene were catalyzed by a new late transition metal complex catalytic system based on bis-(β-ketonaphthylamino) nickel(Ⅱ)/B(C6F5)3/AlEt3.The above catalytic system can polymerize 5-norbornene-2-yl-acetate effectly in a range of 20~90 ℃ and produced poly(5-norbornene-2-yl-acetate)s with moderate molecular mass(Mw=7.0×103~3.1×104 g/mol) and relative narrow molecular mass distributions(Mw/Mn=1.8~2.0).The obtained polymers were characterized by proton and carbon nuclear magnetic resonance,Fourier-transform infrared spectroscopy,differential scanning calorimetry,thermogravimetric analysis and wide-angle X-ray diffraction.Analyses of nuclear magnetic resonance and Fourier-transform infrared spectroscopy indicate that the obtained polymers are vinyl-addition poly(5-norbornene-2-yl-acetate)s,and demonstrate that the above catalytic system initiated 5-norbornene-2-yl-acetate polymerization according to the vinyl-addition mode.Wide-angle X-ray diffraction analysis result shows that poly(5-norbornene-2-yl-acetate) exhibits non-crystallinity but short-range order and long-range disorder,the interchain distance of the polymer is 1.24 nm.The polymer has a better thermal stability(Ts>330 ℃) and is soluble in many common solvents.
Polymerizations of 5-norbornene-2-yl-acetate in toluene were catalyzed by a new late transition metal complex catalytic system based on bis-(β-ketonaphthylamino) nickel(Ⅱ)/B(C6F5)3/AlEt3.The above catalytic system can polymerize 5-norbornene-2-yl-acetate effectly in a range of 20~90 ℃ and produced poly(5-norbornene-2-yl-acetate)s with moderate molecular mass(Mw=7.0×103~3.1×104 g/mol) and relative narrow molecular mass distributions(Mw/Mn=1.8~2.0).The obtained polymers were characterized by proton and carbon nuclear magnetic resonance,Fourier-transform infrared spectroscopy,differential scanning calorimetry,thermogravimetric analysis and wide-angle X-ray diffraction.Analyses of nuclear magnetic resonance and Fourier-transform infrared spectroscopy indicate that the obtained polymers are vinyl-addition poly(5-norbornene-2-yl-acetate)s,and demonstrate that the above catalytic system initiated 5-norbornene-2-yl-acetate polymerization according to the vinyl-addition mode.Wide-angle X-ray diffraction analysis result shows that poly(5-norbornene-2-yl-acetate) exhibits non-crystallinity but short-range order and long-range disorder,the interchain distance of the polymer is 1.24 nm.The polymer has a better thermal stability(Ts>330 ℃) and is soluble in many common solvents.
2009, 26(8): 929-934
Abstract:
Two fluorescent vinyl monomers containing 1,8-naphthalimide segments were synthesized and polymerized via atom transfer radical polymerization(ATRP).The monomers and the homopolymers were characterized by 1H NMR,elemental analysis,UV,fluorescence emission spectroscopy and gel permeation chromatography(GPC).The photophysical properties of the monomers and the homopolymers were studied in detail.Results show that both the monomers and their homopolymers had green emission and solvent effect,and the fluorescence intensity was enhanced with the concentration increased from 1×10-6 mol/L to 1×10-4 mol/L,and the homopolymers had higher quantum yield than the monomers.
Two fluorescent vinyl monomers containing 1,8-naphthalimide segments were synthesized and polymerized via atom transfer radical polymerization(ATRP).The monomers and the homopolymers were characterized by 1H NMR,elemental analysis,UV,fluorescence emission spectroscopy and gel permeation chromatography(GPC).The photophysical properties of the monomers and the homopolymers were studied in detail.Results show that both the monomers and their homopolymers had green emission and solvent effect,and the fluorescence intensity was enhanced with the concentration increased from 1×10-6 mol/L to 1×10-4 mol/L,and the homopolymers had higher quantum yield than the monomers.
2009, 26(8): 935-938
Abstract:
Thiophene-2-carbaldehyde was synthesized from thiophene under the optimized conditions.The product was used to synthesize Schiff base thiophene-2-carbaldehyde by reaction with 4-aminophenol.The thiophene Schiff base was esterified with undecene acid catalyzed by N,N'-dicyclohexylcarbodiimide(DCC)/4-dimethylamiopryidine(DMAP).The structures and liquid crystalline properties of the synthesized compounds were investigated by IR,NMR,and the polarizing optical microscopy(POM).The inhibiting activity of the thiophene Schiff base was tested with the paper strip method,and it displays a good inhibiting activity.
Thiophene-2-carbaldehyde was synthesized from thiophene under the optimized conditions.The product was used to synthesize Schiff base thiophene-2-carbaldehyde by reaction with 4-aminophenol.The thiophene Schiff base was esterified with undecene acid catalyzed by N,N'-dicyclohexylcarbodiimide(DCC)/4-dimethylamiopryidine(DMAP).The structures and liquid crystalline properties of the synthesized compounds were investigated by IR,NMR,and the polarizing optical microscopy(POM).The inhibiting activity of the thiophene Schiff base was tested with the paper strip method,and it displays a good inhibiting activity.
2009, 26(8): 939-943
Abstract:
The effects of HLB value,concentration of Span60-Tween20 composite emulsifier,emulsifying temperature and stirring speed on the critical water content of phase inversion emulsifying(Rf) and emulsion stability of epoxy resin E-44 were investigated.The experimental results show that emulsion at HLB=13 had a smallest Rf and was most stable.Rf decreased and the emulsion stability increased with the increase of the emulsifier concentration,and Rf kept constant when the emulsifier mass fraction was over 10%.At 60~70 ℃,Rf wasn't changed obviously,however,when emulsifying temperature was higher than 75 ℃,Rf increased with the increase of temperature,and the emulsion was stable at 60~80 ℃,but the stability decreased when the temperature was over 90℃.At a too low stirring speed,Rf was large and it was difficult to create a phase inversion;when stirring speed was over 400 r/min,Rf decreased with the increase of stirring speed,and emulsion had a best stability under 600 r/min,yet the stability would decrease when stirring speed was over 800 r/min;though the Rf was very small and phase inversion took place easily.
The effects of HLB value,concentration of Span60-Tween20 composite emulsifier,emulsifying temperature and stirring speed on the critical water content of phase inversion emulsifying(Rf) and emulsion stability of epoxy resin E-44 were investigated.The experimental results show that emulsion at HLB=13 had a smallest Rf and was most stable.Rf decreased and the emulsion stability increased with the increase of the emulsifier concentration,and Rf kept constant when the emulsifier mass fraction was over 10%.At 60~70 ℃,Rf wasn't changed obviously,however,when emulsifying temperature was higher than 75 ℃,Rf increased with the increase of temperature,and the emulsion was stable at 60~80 ℃,but the stability decreased when the temperature was over 90℃.At a too low stirring speed,Rf was large and it was difficult to create a phase inversion;when stirring speed was over 400 r/min,Rf decreased with the increase of stirring speed,and emulsion had a best stability under 600 r/min,yet the stability would decrease when stirring speed was over 800 r/min;though the Rf was very small and phase inversion took place easily.
2009, 26(8): 944-947
Abstract:
Polyacrylate-vinylidene chloride/montmorillonite copolymer composite emulsion was prepared by seed emulsion polymerization with vinylidene chloride and montmorillonite as the modifiers.The influences of the montmorillonite content on the composite emulsion particle diameter,tensile strength,elongation at break and thermal stability were studied.The results show that the average particle size of PEA-VDC/MMT copo-lymer latex particles increased from 141 nm to 243 nm when the montomorillonite content was increased from 1% to 5%.The largest tensile strength and the elongation at break of the composite membrane were respe-ctively 3.23 MPa and 1 330% when the montomorillonite content was 2%.When the montomorillonite content was increased from 1% to 4%,the char yield and thermal decomposition temperature of PEA-VDC were enhanced,and the copolymer's thermal stability was strengthened,too.
Polyacrylate-vinylidene chloride/montmorillonite copolymer composite emulsion was prepared by seed emulsion polymerization with vinylidene chloride and montmorillonite as the modifiers.The influences of the montmorillonite content on the composite emulsion particle diameter,tensile strength,elongation at break and thermal stability were studied.The results show that the average particle size of PEA-VDC/MMT copo-lymer latex particles increased from 141 nm to 243 nm when the montomorillonite content was increased from 1% to 5%.The largest tensile strength and the elongation at break of the composite membrane were respe-ctively 3.23 MPa and 1 330% when the montomorillonite content was 2%.When the montomorillonite content was increased from 1% to 4%,the char yield and thermal decomposition temperature of PEA-VDC were enhanced,and the copolymer's thermal stability was strengthened,too.
2009, 26(8): 948-951
Abstract:
The transparent neodymium-doped phosphate glass-ceramic was prepared by the method of melting and crystallization.The obtained glas-ceramic was characterized by DTA,XRD,SEM,UV-Vis-NIR and fluorescence spectrometry.The results indicate that the main crystal phase of the transparent glass-ceramic is Al2SiO5.The temperature of nuclear generation is in a range from 490~540 ℃,and the time of treatment is about 1~2 h.The temperature of crystallization is at 550 ℃,and the time of treatment is about 1~3 h.The average grain size is 90 nm.The transparency of the glass-ceramic can reach to 69%,which decreases with the incerease of the heat-treatment time.Because of the concentration increase of Nd3+ in the crystal phase after the heat treatment,the peak of the glass-ceramic is stronger than the host glass at 1 056 nm in fluore-scence spectra.
The transparent neodymium-doped phosphate glass-ceramic was prepared by the method of melting and crystallization.The obtained glas-ceramic was characterized by DTA,XRD,SEM,UV-Vis-NIR and fluorescence spectrometry.The results indicate that the main crystal phase of the transparent glass-ceramic is Al2SiO5.The temperature of nuclear generation is in a range from 490~540 ℃,and the time of treatment is about 1~2 h.The temperature of crystallization is at 550 ℃,and the time of treatment is about 1~3 h.The average grain size is 90 nm.The transparency of the glass-ceramic can reach to 69%,which decreases with the incerease of the heat-treatment time.Because of the concentration increase of Nd3+ in the crystal phase after the heat treatment,the peak of the glass-ceramic is stronger than the host glass at 1 056 nm in fluore-scence spectra.
2009, 26(8): 952-955
Abstract:
Experimental research on the desulfurization of flue gas was simulated with 0.3 mol/L amine solutions of ethanolamine,ethylenediamine and so on.Desulfurization efficiency was studied by iodometry titration.Absorption capacity of SO2,oxidation of absorbed SO2 and desorption efficiency of SO2 were researched via ion chromatography,and the effects of the number of cycles on the desulfurization efficiency and SO2 content of rich absorbent were studied.The results show that the desulfurization efficiency of all the absorbents were maintained at 99% for 30 min.After 60 min,the desulfurization efficiency of ethylenediamine solutions remained 99%,but that of alcohol amine solutions decreased significantly.The absorption capacity of the ethylenediamine solution for SO2 was 455 mg/L,much higher than that of the alcohol amine solution.With boric acid added to the ethylenediamine solution,the absorption capacity was slightly lower(450 mg/L),but the oxidation efficiency of absorbed SO2 reduced from 1.14% to 0.29%.At the same time,the desorption efficiency of SO2 increased from 38.0% to 59.0%.Absorption-desorption cycle experiments indicated that the average desulfurization efficiency of the ethylenediamine/boric acid solution reached above 99%,and SO2 content of rich absorbents decreased from 0.44 mol/L to 0.40 mol/L.The results suggest the desulfurization effect of the ethylenediamine/boric acid solution is excellent as the flue gas absorbent.
Experimental research on the desulfurization of flue gas was simulated with 0.3 mol/L amine solutions of ethanolamine,ethylenediamine and so on.Desulfurization efficiency was studied by iodometry titration.Absorption capacity of SO2,oxidation of absorbed SO2 and desorption efficiency of SO2 were researched via ion chromatography,and the effects of the number of cycles on the desulfurization efficiency and SO2 content of rich absorbent were studied.The results show that the desulfurization efficiency of all the absorbents were maintained at 99% for 30 min.After 60 min,the desulfurization efficiency of ethylenediamine solutions remained 99%,but that of alcohol amine solutions decreased significantly.The absorption capacity of the ethylenediamine solution for SO2 was 455 mg/L,much higher than that of the alcohol amine solution.With boric acid added to the ethylenediamine solution,the absorption capacity was slightly lower(450 mg/L),but the oxidation efficiency of absorbed SO2 reduced from 1.14% to 0.29%.At the same time,the desorption efficiency of SO2 increased from 38.0% to 59.0%.Absorption-desorption cycle experiments indicated that the average desulfurization efficiency of the ethylenediamine/boric acid solution reached above 99%,and SO2 content of rich absorbents decreased from 0.44 mol/L to 0.40 mol/L.The results suggest the desulfurization effect of the ethylenediamine/boric acid solution is excellent as the flue gas absorbent.
2009, 26(8): 956-960
Abstract:
This paper describes a new deep treating agent JY-8.The new deep treating agent JY-8 is a good fixative and flocculant,which can form high strength gels with polymers,consolidating and flocculating residual polymers in the reservoir effectively,realizing unification of the two agents,and achieving the goals of deep profile control and oil displacement for the formations.At the same time,gelation time and gel strength can be regulated by adjusting the used-amount of the new deep treating agent JY-8.Laboratory evaluations and field applications indicated that new deep treating agent JY-8 increased utilization ratio of residual polymers in the reservoir from 8% to 15.65%,increased recovery ratio of water flooding after polymer flooding from 10.3% to 18.1%,and played a good oil increment effect on oil wells.
This paper describes a new deep treating agent JY-8.The new deep treating agent JY-8 is a good fixative and flocculant,which can form high strength gels with polymers,consolidating and flocculating residual polymers in the reservoir effectively,realizing unification of the two agents,and achieving the goals of deep profile control and oil displacement for the formations.At the same time,gelation time and gel strength can be regulated by adjusting the used-amount of the new deep treating agent JY-8.Laboratory evaluations and field applications indicated that new deep treating agent JY-8 increased utilization ratio of residual polymers in the reservoir from 8% to 15.65%,increased recovery ratio of water flooding after polymer flooding from 10.3% to 18.1%,and played a good oil increment effect on oil wells.
2009, 26(8): 961-965
Abstract:
The active intermediate substitution-4-formacyl pyrazole was obtained from benzene hydrazone via the Vilsmeier-Haak reaction.Then it reacted with 4-substituted aryloxyacetyl hydrazine to form compounds 3.Finally Bis-heterocyclic compounds 4 were synthesized via cyclic reaction.All the newly synthesized compounds have not been reported and their structures have been established on the basis of IR,1H NMR,MS spectral data and elemental analysis.Compounds 3 and 4 underwent a preliminary test of antibacterial activity against Fusarium oxyaporium,Verticillium dahliae,Rhizoctonia solani,Pychium aphanidermatum,Alternaria solani,Sclerotinia sclerotiorum.The results show that the inhibiting rates of the bis-heterocyclic compounds 4 are higher than those of the pyrazole hydrazones 3 obviously.Compounds 3d and 3e showed good inhibitory activities(>80%) against Alternaria solani and Sclerotinia sclerotiorum at a concentration of 50 mg/L.In contrast,bis-heterocyclic compounds 4 have obviously inhibitory activities(>70%) against these six germs and compounds 4d and 4e showed inhibitory activities(>95%) against Rhizoctonia solani.
The active intermediate substitution-4-formacyl pyrazole was obtained from benzene hydrazone via the Vilsmeier-Haak reaction.Then it reacted with 4-substituted aryloxyacetyl hydrazine to form compounds 3.Finally Bis-heterocyclic compounds 4 were synthesized via cyclic reaction.All the newly synthesized compounds have not been reported and their structures have been established on the basis of IR,1H NMR,MS spectral data and elemental analysis.Compounds 3 and 4 underwent a preliminary test of antibacterial activity against Fusarium oxyaporium,Verticillium dahliae,Rhizoctonia solani,Pychium aphanidermatum,Alternaria solani,Sclerotinia sclerotiorum.The results show that the inhibiting rates of the bis-heterocyclic compounds 4 are higher than those of the pyrazole hydrazones 3 obviously.Compounds 3d and 3e showed good inhibitory activities(>80%) against Alternaria solani and Sclerotinia sclerotiorum at a concentration of 50 mg/L.In contrast,bis-heterocyclic compounds 4 have obviously inhibitory activities(>70%) against these six germs and compounds 4d and 4e showed inhibitory activities(>95%) against Rhizoctonia solani.
2009, 26(8): 966-970
Abstract:
In 0.05 mol/L(pH=1.3) HCl,SDBS combined with methylene blue(MB) to form an ion-association complex with a composition ratio of 2:1 by electrostatic and hydrophobic interactions.As a result,the intensities of RRS,FDS,and SOS spectra were enhanced greatly.The maximum wavelengths of RRS,SOS and FDS were located at 310 nm,648 nm and 341 nm respectively,and the scattering intensities were propo-rtional to the concentration of MB.The detection of MB using these three compounds has very high sensitivities,and the detection limits were 1.2×10-9 g/mL for RRS,1.4×10-9 g/mL for SOS and 1.7×10-9 g/mL for FDS,respectively.At the same time,the methods have better selectivity.Based on the above results,a new spectral method for the determination of trace amounts of MB has been developed.It can be applied to the determination of MB in human serum with a satisfactory result,and the recoveries are 94.4%~103.7%.In this work,the optimum conditions of the reaction and the effects of coexisting substances were investigated.In addition,the reaction mechanism and the reasons of enhancement of resonance light scattering were discussed.
In 0.05 mol/L(pH=1.3) HCl,SDBS combined with methylene blue(MB) to form an ion-association complex with a composition ratio of 2:1 by electrostatic and hydrophobic interactions.As a result,the intensities of RRS,FDS,and SOS spectra were enhanced greatly.The maximum wavelengths of RRS,SOS and FDS were located at 310 nm,648 nm and 341 nm respectively,and the scattering intensities were propo-rtional to the concentration of MB.The detection of MB using these three compounds has very high sensitivities,and the detection limits were 1.2×10-9 g/mL for RRS,1.4×10-9 g/mL for SOS and 1.7×10-9 g/mL for FDS,respectively.At the same time,the methods have better selectivity.Based on the above results,a new spectral method for the determination of trace amounts of MB has been developed.It can be applied to the determination of MB in human serum with a satisfactory result,and the recoveries are 94.4%~103.7%.In this work,the optimum conditions of the reaction and the effects of coexisting substances were investigated.In addition,the reaction mechanism and the reasons of enhancement of resonance light scattering were discussed.
2009, 26(8): 971-975
Abstract:
A series of molecularly imprinting polymers(MIPs) at different ratios of template to functional monomer were prepared with phenolphthalein as the template and 4-vinylpyridine as the functional monomer.The surface features of the polymers were analyzed by scanning electron micrography.The static equilibrium binding experiments were performed to investigate the adsorption property and selective recognition of the MIPs for phenolphthalein and its analogues.It showed that the saturated adsorption was achieved in 3 h.The best imprinting effect was observed when the molar ratio of the template molecules,functional monomer and crosslinker was 1:6:20.Scatchard analysis shows that two classes of binding sites were formed in the imprinted polymers in the concentrations range studied.The calculated dissociation constant Kd1 and the apparent maximum binding capacities Qmax1 for the high affinity sites are 0.63 mmol/L and 25.4 μmol/g,while Kd2 and Qmax2 for the low affinity sites are 3.5 mmol/L and 61.9 μmol/g,respectively.The molecularly imprinting polymers display a higher selectivity for phenolphthalein compared with the analogues of phenolphthalein.
A series of molecularly imprinting polymers(MIPs) at different ratios of template to functional monomer were prepared with phenolphthalein as the template and 4-vinylpyridine as the functional monomer.The surface features of the polymers were analyzed by scanning electron micrography.The static equilibrium binding experiments were performed to investigate the adsorption property and selective recognition of the MIPs for phenolphthalein and its analogues.It showed that the saturated adsorption was achieved in 3 h.The best imprinting effect was observed when the molar ratio of the template molecules,functional monomer and crosslinker was 1:6:20.Scatchard analysis shows that two classes of binding sites were formed in the imprinted polymers in the concentrations range studied.The calculated dissociation constant Kd1 and the apparent maximum binding capacities Qmax1 for the high affinity sites are 0.63 mmol/L and 25.4 μmol/g,while Kd2 and Qmax2 for the low affinity sites are 3.5 mmol/L and 61.9 μmol/g,respectively.The molecularly imprinting polymers display a higher selectivity for phenolphthalein compared with the analogues of phenolphthalein.
2009, 26(8): 976-980
Abstract:
Different nickel salt precursors,namely,nickel acetylacetone,nickel chlorate,nickel nitrate and nickel acetate,were used to prepare Ni/C catalysts for the vapor phase carbonylation of ethanol.The activity testing results reveal that the Ni/C catalyst prepared from nickel acetate showed maximal catalytic activity for the carbonylation of ethanol,with an ethanol conversion of 96.1% and a propionic acid selectivity of 95.7% in comparison with that prepared from other nickel precursors,while the catalyst prepared from acetylacetone nickel showed a minimum activity with an ethanol conversion of 68.9% and a propionic acid selectivity of 27.1%.The Ni/C catalysts were characterized by means of BET measurement,metal dispersion test,H2 temperature-programmed reduction(H2-TPR) and XRD.It was found that the catalytic performances of the Ni/C catalysts depended,to a great degree,on the interaction between nickel species and active carbon support.The nickel acetate molecule was confirmed to be easily adsorbed on the surface of active carbon,leading to a stronger interaction between nickel species and active carbon support,thereby increasing the absorption capacity of CO.Meanwhile,a better dispersion of the active component and smaller nickel crysta-llites were found.
Different nickel salt precursors,namely,nickel acetylacetone,nickel chlorate,nickel nitrate and nickel acetate,were used to prepare Ni/C catalysts for the vapor phase carbonylation of ethanol.The activity testing results reveal that the Ni/C catalyst prepared from nickel acetate showed maximal catalytic activity for the carbonylation of ethanol,with an ethanol conversion of 96.1% and a propionic acid selectivity of 95.7% in comparison with that prepared from other nickel precursors,while the catalyst prepared from acetylacetone nickel showed a minimum activity with an ethanol conversion of 68.9% and a propionic acid selectivity of 27.1%.The Ni/C catalysts were characterized by means of BET measurement,metal dispersion test,H2 temperature-programmed reduction(H2-TPR) and XRD.It was found that the catalytic performances of the Ni/C catalysts depended,to a great degree,on the interaction between nickel species and active carbon support.The nickel acetate molecule was confirmed to be easily adsorbed on the surface of active carbon,leading to a stronger interaction between nickel species and active carbon support,thereby increasing the absorption capacity of CO.Meanwhile,a better dispersion of the active component and smaller nickel crysta-llites were found.
2009, 26(8): 981-984
Abstract:
The immobilization of alcohol dehydrogenase(ADH) with cetyl trimethyl ammonium bromide(CTAB)-octane-hexanol reversed micelle system was performed.The effects of w0([water]/[CTAB]),pH value in enzyme solution,concentrations of CTAB and hexanol on the immobilization of ADH were studied.The result on the kinetic characterizations of the free and immobilized enzyme indicates that optimum pH values for the enzymatic reactions were 8.2 and 8.8,the optimum temperatures were 31 ℃ and 20 ℃,respectively.The Km values for alcohol were 12 mmol/L and 7.4 mmol/L,respectively.When the enzyme was deposited for 150 min at 30 ℃,the activities were lost by 90% and 50% for the free and the immobilized enzymes respectively,indicating that the immobilized ADH in reversed micelle has a better thermal stability.
The immobilization of alcohol dehydrogenase(ADH) with cetyl trimethyl ammonium bromide(CTAB)-octane-hexanol reversed micelle system was performed.The effects of w0([water]/[CTAB]),pH value in enzyme solution,concentrations of CTAB and hexanol on the immobilization of ADH were studied.The result on the kinetic characterizations of the free and immobilized enzyme indicates that optimum pH values for the enzymatic reactions were 8.2 and 8.8,the optimum temperatures were 31 ℃ and 20 ℃,respectively.The Km values for alcohol were 12 mmol/L and 7.4 mmol/L,respectively.When the enzyme was deposited for 150 min at 30 ℃,the activities were lost by 90% and 50% for the free and the immobilized enzymes respectively,indicating that the immobilized ADH in reversed micelle has a better thermal stability.
2009, 26(8): 985-988
Abstract:
The Pd/C catalyst as the anodic catalyst in the direct formic acid fuel cell(DFAFC) is prepared with the improved liquid phase reduction method,where Pd/C catalyst with small average size and relative crystalinity of the Pd particles can be prepared if suitable amounts of NaOH are added before the addition of NaBH4.The average size and relative crystalinity of Pd particles in the Pd/C catalyst prepared are related to the concentration ratio of NaOH and PdCl2.The average size and relative crystalinity of the Pd particles in the Pd/C catalyst without addition of NaOH are 20.2 nm and 6.29,respectively.When the concentration ratio of NaOH and PdCl2 is 10,the average size and relative crystalinity of Pd particles in the Pd/C catalyst are 6.7 nm and 3.45,respectively,which exhibits an excellent electrocatalytic activity and stability for the oxidation of formic acid.Because the improved liquid phase reduction method is simple,it may have the potential for practical applications.
The Pd/C catalyst as the anodic catalyst in the direct formic acid fuel cell(DFAFC) is prepared with the improved liquid phase reduction method,where Pd/C catalyst with small average size and relative crystalinity of the Pd particles can be prepared if suitable amounts of NaOH are added before the addition of NaBH4.The average size and relative crystalinity of Pd particles in the Pd/C catalyst prepared are related to the concentration ratio of NaOH and PdCl2.The average size and relative crystalinity of the Pd particles in the Pd/C catalyst without addition of NaOH are 20.2 nm and 6.29,respectively.When the concentration ratio of NaOH and PdCl2 is 10,the average size and relative crystalinity of Pd particles in the Pd/C catalyst are 6.7 nm and 3.45,respectively,which exhibits an excellent electrocatalytic activity and stability for the oxidation of formic acid.Because the improved liquid phase reduction method is simple,it may have the potential for practical applications.
2009, 26(8): 989-992
Abstract:
LiV3O8 cathode nanomaterials were synthesized by a hydrothermal route at different reaction temperatures.The structures,morphologies and proprieties of the samples were investigated by XRD,TEM,galvanostatic charge-discharge,cyclic voltammetry(CV),and electrochemical impedance spectroscopy(EIS) techniques.With increase of hydrothermal temperature,the diameter of the particles increased,the size distribution became inhomogeneous,and the charge transfer resistance of the LiV3O8 electrode was decreased,which is of benefit to strip and insert of lithium-ion during the charging-discharging process.The sample synthesized at a hydrothermal temperature 180 ℃ has the highest discharge capacity and a good reversibility.Its specific discharge capacity is up to 290 mA·h/g in a range of 1.8~3.8 V in the first cycle.After 30 cycles,the discharge capacity of this electrode material is still above 200 mA·h/g.That is to say,there is some defect-amorphous in the structure of the materials,and there is a certain dimensional distributing of the particles,which can improve the electrochemical performances of the LiV3O8 cathode nanomaterials.
LiV3O8 cathode nanomaterials were synthesized by a hydrothermal route at different reaction temperatures.The structures,morphologies and proprieties of the samples were investigated by XRD,TEM,galvanostatic charge-discharge,cyclic voltammetry(CV),and electrochemical impedance spectroscopy(EIS) techniques.With increase of hydrothermal temperature,the diameter of the particles increased,the size distribution became inhomogeneous,and the charge transfer resistance of the LiV3O8 electrode was decreased,which is of benefit to strip and insert of lithium-ion during the charging-discharging process.The sample synthesized at a hydrothermal temperature 180 ℃ has the highest discharge capacity and a good reversibility.Its specific discharge capacity is up to 290 mA·h/g in a range of 1.8~3.8 V in the first cycle.After 30 cycles,the discharge capacity of this electrode material is still above 200 mA·h/g.That is to say,there is some defect-amorphous in the structure of the materials,and there is a certain dimensional distributing of the particles,which can improve the electrochemical performances of the LiV3O8 cathode nanomaterials.
2009, 26(8): 993-995
Abstract:
A method for identifying the sulfur compounds in industrial mixed alkanes was developed.Mercaptan was first extracted from the sample with a KOH solution,and then the residue was treated with a AgNO3 solution,which precipitated with thioether and was separated from thiophene.The mercaptan,thioether and thiophene were separated and enriched from industrial mixed alkanes before analysis by GC-MS.30 thioether compounds and 5 mercaptan compounds in industrial mixed alkanes were detected.
A method for identifying the sulfur compounds in industrial mixed alkanes was developed.Mercaptan was first extracted from the sample with a KOH solution,and then the residue was treated with a AgNO3 solution,which precipitated with thioether and was separated from thiophene.The mercaptan,thioether and thiophene were separated and enriched from industrial mixed alkanes before analysis by GC-MS.30 thioether compounds and 5 mercaptan compounds in industrial mixed alkanes were detected.
2009, 26(8): 996-998
Abstract:
Hypoxanthine,xanthine and adenine in some animal drug materials were determined by means of HPLC with methanol/water as the mobile phase and a UV detector.This process of sample preparation was improved and the conditions of HPLC were also optimized.The detection limits of hypoxanthine,xanthine and adenine were 0.012×10-6,0.041×10-6,0.042×10-6 g/mL,respectively.The intra-day precisions(RSD) of hypoxanthine,xanthine and adenine were less than 4.1%,7.3% and 4.5%,respectively.The inter-day precisions(RSD) of hypoxanthine,xanthine and adenine were less than 5.8%,2.9% and 3.1%,respectively.The recovery rates of the four samples with added specimen were in a range of 94% to 107%.
Hypoxanthine,xanthine and adenine in some animal drug materials were determined by means of HPLC with methanol/water as the mobile phase and a UV detector.This process of sample preparation was improved and the conditions of HPLC were also optimized.The detection limits of hypoxanthine,xanthine and adenine were 0.012×10-6,0.041×10-6,0.042×10-6 g/mL,respectively.The intra-day precisions(RSD) of hypoxanthine,xanthine and adenine were less than 4.1%,7.3% and 4.5%,respectively.The inter-day precisions(RSD) of hypoxanthine,xanthine and adenine were less than 5.8%,2.9% and 3.1%,respectively.The recovery rates of the four samples with added specimen were in a range of 94% to 107%.
2009, 26(8): 999-1001
Abstract:
In a pH=6.9 BR buffer medium,brilliant cresyl blue reacted with inosine to form ion-association complex.The maximum fading wavelength was located at 630 nm.The fading intensity is proportional to the concentration of inosine.The concentration of inosine in a range of 0.18×10-6~6.0×10-6 g/mL obeys Beer's Law.The correlation coefficient is 0.999 3,the molar absorptivity is 1.13×104 L/(mol·cm),the detection limit is 53.5×10-9 g/mL.The method is simple,accurate and sensitive,and it was applied to the determination of inosine in tablet samples with satisfactory results.
In a pH=6.9 BR buffer medium,brilliant cresyl blue reacted with inosine to form ion-association complex.The maximum fading wavelength was located at 630 nm.The fading intensity is proportional to the concentration of inosine.The concentration of inosine in a range of 0.18×10-6~6.0×10-6 g/mL obeys Beer's Law.The correlation coefficient is 0.999 3,the molar absorptivity is 1.13×104 L/(mol·cm),the detection limit is 53.5×10-9 g/mL.The method is simple,accurate and sensitive,and it was applied to the determination of inosine in tablet samples with satisfactory results.
2009, 26(8): 1002-1004
Abstract:
Oxybutynin chloride enantiomers were separated with capillary zone electrophoresis(CZE) with hydroxypropyl-β-cyclodextrin(HP-β-CD) as the chiral selector,and the difference between enantioseparation abilities of HP-β-CD and β-CD was compared.The best experimental conditions for hydrochloric oxybutynin enantiomers in baseline separation were obtained,including water-soluble hydroxypropyl-β-cyclodextrin concentration,background buffer pH,capillary temperature,voltage and the amount of three hydroxymethyl-methane in phosphate background buffer,and so on.The method is simple,quick with an improved reprodu-cibility.
Oxybutynin chloride enantiomers were separated with capillary zone electrophoresis(CZE) with hydroxypropyl-β-cyclodextrin(HP-β-CD) as the chiral selector,and the difference between enantioseparation abilities of HP-β-CD and β-CD was compared.The best experimental conditions for hydrochloric oxybutynin enantiomers in baseline separation were obtained,including water-soluble hydroxypropyl-β-cyclodextrin concentration,background buffer pH,capillary temperature,voltage and the amount of three hydroxymethyl-methane in phosphate background buffer,and so on.The method is simple,quick with an improved reprodu-cibility.
