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2012 Volume 29 Issue 4
2012, 29(4): 367-375
doi: 10.3724/SP.J.1095.2012.00225
Abstract:
The solubility of carbon dioxide in traditional room-temperature ionic liquids(RTILs),functionalized ionic liquids or task-specific ionic liquids(TSILs),supported ionic-liquid membranes(SILMs) and polymerized ionic liquids(poly(RTIL)) are summarized.The absorption capacity of TSILs is greater than that of RTILs,but the high viscosity of TSILs can be an operational drawback.SILMs show remarkably high selectivity compared to polymeric membranes,however,the instability of SILMs is recognized as a serious problem.This brief survey of the current development on the imidazolium cation ionic-liquid mediated CO2 capture suggests that CO2 capture by ionic liquids is a feasible practice.
The solubility of carbon dioxide in traditional room-temperature ionic liquids(RTILs),functionalized ionic liquids or task-specific ionic liquids(TSILs),supported ionic-liquid membranes(SILMs) and polymerized ionic liquids(poly(RTIL)) are summarized.The absorption capacity of TSILs is greater than that of RTILs,but the high viscosity of TSILs can be an operational drawback.SILMs show remarkably high selectivity compared to polymeric membranes,however,the instability of SILMs is recognized as a serious problem.This brief survey of the current development on the imidazolium cation ionic-liquid mediated CO2 capture suggests that CO2 capture by ionic liquids is a feasible practice.
2012, 29(4): 376-382
doi: 10.3724/SP.J.1095.2012.00224
Abstract:
Poly(acrylic acid sodium)/humic acid superabsorbent composite was prepared in aqueous solution by using glow-discharge electrolysis plasma.Acrylic acid and humic acid were used as raw materials and N,N-methylenebisacrylamide as crosslinking agent.The effects of absorbency were examined in detail,such as the discharge voltage,crosslinking agent,neutralization degree of acrylic acid,polymerization temperature,amounts of sodium humate and acrylic acid.The swelling rate in 0.9% sodium chloride solution and the swelling behavior in various pH value solutions were also investigated.The structure and thermal stability of the resulting products were also characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis.The results show that the discharge voltage,amount of crosslinking agent,sodium humate,acrylic acid,neutralization degree of acrylic acid,reaction temperature were 470 V,0.6%,4%,10%,60% and 70℃,respectively,under the optimal conditions.The superabsorbent has higher water absorbency,i.e.1152 g/g for distilled water and 89 g/g for 0.9% sodium chloride solution.The retention rate of the composite is about 44.3% after heating to 800℃.
Poly(acrylic acid sodium)/humic acid superabsorbent composite was prepared in aqueous solution by using glow-discharge electrolysis plasma.Acrylic acid and humic acid were used as raw materials and N,N-methylenebisacrylamide as crosslinking agent.The effects of absorbency were examined in detail,such as the discharge voltage,crosslinking agent,neutralization degree of acrylic acid,polymerization temperature,amounts of sodium humate and acrylic acid.The swelling rate in 0.9% sodium chloride solution and the swelling behavior in various pH value solutions were also investigated.The structure and thermal stability of the resulting products were also characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis.The results show that the discharge voltage,amount of crosslinking agent,sodium humate,acrylic acid,neutralization degree of acrylic acid,reaction temperature were 470 V,0.6%,4%,10%,60% and 70℃,respectively,under the optimal conditions.The superabsorbent has higher water absorbency,i.e.1152 g/g for distilled water and 89 g/g for 0.9% sodium chloride solution.The retention rate of the composite is about 44.3% after heating to 800℃.
2012, 29(4): 383-387
doi: 10.3724/SP.J.1095.2012.00185
Abstract:
A Schiff base-type chelating resin(SACPS) was prepared by two polymeric reaction steps using chloromethylated polystyrene microspheres(CMCPS) as starting material.Firstly,in the presence of catalyst KI,the Delepine reaction between the chloromethyl groups and hexamethylene tetramine(HMTA) was carried out to yield aminomethyl(AM) group-modified CPS microspheres(AMCPS).Then the reaction between AMCPS microspheres and salicylaldehyde(SA) resulted the formation of Schiff base-type chelating resin(SACPS).The aminomethyl group-modification of CMCPS was systematically investigated,and the effects of main factors on the Delepine reaction were examined.The experimental results showed that KI has a strong catalytic activity toward the Delepine reaction.Higher solvent polarity favored the fracture of C-Cl bond of the benzyl chloride group,and could accelerate the Delepine reaction.The increase of the reaction temperature is also advantageous to the reaction.DMSO is a suitable solvent and 80℃ is an appropriate temperature.The prepared SACPS resin possesses strong chelating ability for Cu2+.
A Schiff base-type chelating resin(SACPS) was prepared by two polymeric reaction steps using chloromethylated polystyrene microspheres(CMCPS) as starting material.Firstly,in the presence of catalyst KI,the Delepine reaction between the chloromethyl groups and hexamethylene tetramine(HMTA) was carried out to yield aminomethyl(AM) group-modified CPS microspheres(AMCPS).Then the reaction between AMCPS microspheres and salicylaldehyde(SA) resulted the formation of Schiff base-type chelating resin(SACPS).The aminomethyl group-modification of CMCPS was systematically investigated,and the effects of main factors on the Delepine reaction were examined.The experimental results showed that KI has a strong catalytic activity toward the Delepine reaction.Higher solvent polarity favored the fracture of C-Cl bond of the benzyl chloride group,and could accelerate the Delepine reaction.The increase of the reaction temperature is also advantageous to the reaction.DMSO is a suitable solvent and 80℃ is an appropriate temperature.The prepared SACPS resin possesses strong chelating ability for Cu2+.
2012, 29(4): 388-391
doi: 10.3724/SP.J.1095.2012.00192
Abstract:
The volume of unit cell,the scattering invariant Q,and the crystalline lamellar long period of polycaprolactone in the processes of cooling and heating covering α and β relaxation were studied using X-ray small angle scattering and wide angle diffraction.Experimental results indicate that the behavior of crystalline and amorphous regions is interlinked in the whole process.It was found that the variation of the unit cell volume is reversible.An abrupt variation of the unit cell volume at-90℃ was caused by the freeze or activation of the β relaxation of tie molecules,and thus the change of expansion coefficient of the unit cell volume.The variations of scattering invariant Q with temperature are also reversible but having a transition point due to α relaxation.Because of the occurrence of insertion crystallization mode in the amorphous regions in the process of cooling,the temperature required to melt the crystals becomes higher with respect to the crystallization temperature.Therefore,the long period is not fully reversible in the processes of cooling and heating.
The volume of unit cell,the scattering invariant Q,and the crystalline lamellar long period of polycaprolactone in the processes of cooling and heating covering α and β relaxation were studied using X-ray small angle scattering and wide angle diffraction.Experimental results indicate that the behavior of crystalline and amorphous regions is interlinked in the whole process.It was found that the variation of the unit cell volume is reversible.An abrupt variation of the unit cell volume at-90℃ was caused by the freeze or activation of the β relaxation of tie molecules,and thus the change of expansion coefficient of the unit cell volume.The variations of scattering invariant Q with temperature are also reversible but having a transition point due to α relaxation.Because of the occurrence of insertion crystallization mode in the amorphous regions in the process of cooling,the temperature required to melt the crystals becomes higher with respect to the crystallization temperature.Therefore,the long period is not fully reversible in the processes of cooling and heating.
2012, 29(4): 392-396
doi: 10.3724/SP.J.1095.2012.00254
Abstract:
A cardanol derivative(1) with photo-initiating activity has been synthesized in 86% yield using cardanol and 4-bromomethyl benzophenone as precursors.The photo-initiating performance of the derivative 1 is better than common benzophenone according to the results of the controlled experiments.The derivative 1 can be completely cured within 30 s under UV irradiation without the presence of any photoinitiator.Furthermore,the mixtures of the derivative 1 and cardanol with various ratios can also be cured under UV irradiation that the UV-curing time is prolonged up to dozens of minutes with the increase of cardanol content.The resulting cured films show relatively high hardness(3H-5H),excellent solvent,acid and base resistance,which have potential application in anti-corrosion coatings.
A cardanol derivative(1) with photo-initiating activity has been synthesized in 86% yield using cardanol and 4-bromomethyl benzophenone as precursors.The photo-initiating performance of the derivative 1 is better than common benzophenone according to the results of the controlled experiments.The derivative 1 can be completely cured within 30 s under UV irradiation without the presence of any photoinitiator.Furthermore,the mixtures of the derivative 1 and cardanol with various ratios can also be cured under UV irradiation that the UV-curing time is prolonged up to dozens of minutes with the increase of cardanol content.The resulting cured films show relatively high hardness(3H-5H),excellent solvent,acid and base resistance,which have potential application in anti-corrosion coatings.
2012, 29(4): 397-401
doi: 10.3724/SP.J.1095.2012.00244
Abstract:
Azabicyclo compounds of 1,4-benxodiazine,pyridopyrazine,1H-benzimidazole,3H-imidazopyridine were prepared from o-phenylenediamine or 2,3-diaminopyridine reacted with carbonyl compounds.The effects of reaction medium,pH,time and other factors on the reactions were invesitigated.The results showed that the yield of pyridopyrazine could reach 89.4% when refluxed in propanol for 1 h at pH=9 adjusted by methanol sodium.The yields for 1,4-benxodiazine could be increased to 98.3% in aqueous medium with pH=9 adjusted by sodium sulfite at 60℃ after 40 min reaction.Here,the purification of target product could be achieved via a low temperature standing process instead of the vacuum distillation method.The optimized conditions for the other two compounds are:refluxing o-phenylenediamine for 2 h in 88% formic acid solution yielding 1H-benzimidazole with 92% yield;refluxing 2,3-diaminopyridine with triethoxy methane for 3 h followed by adding concentrated hydrochloric acid for another 1 h giving 3H-imidazopyridine with 84.2% yield.
Azabicyclo compounds of 1,4-benxodiazine,pyridopyrazine,1H-benzimidazole,3H-imidazopyridine were prepared from o-phenylenediamine or 2,3-diaminopyridine reacted with carbonyl compounds.The effects of reaction medium,pH,time and other factors on the reactions were invesitigated.The results showed that the yield of pyridopyrazine could reach 89.4% when refluxed in propanol for 1 h at pH=9 adjusted by methanol sodium.The yields for 1,4-benxodiazine could be increased to 98.3% in aqueous medium with pH=9 adjusted by sodium sulfite at 60℃ after 40 min reaction.Here,the purification of target product could be achieved via a low temperature standing process instead of the vacuum distillation method.The optimized conditions for the other two compounds are:refluxing o-phenylenediamine for 2 h in 88% formic acid solution yielding 1H-benzimidazole with 92% yield;refluxing 2,3-diaminopyridine with triethoxy methane for 3 h followed by adding concentrated hydrochloric acid for another 1 h giving 3H-imidazopyridine with 84.2% yield.
2012, 29(4): 402-409
doi: 10.3724/SP.J.1095.2012.00251
Abstract:
A series of O6-substituted purine derivatives was designed and prepared through an efficient and convenient method with 4-amino-pyridine as the catalyst in methanol solvent.Under optimized conditions:n(6-chloropurine):n(4-amino-pyridine):n(triethylamine)=10:1:4,refluxing for 5~7 h,the yield of 6-alkoxy purine was greater than 85%.Studies showed that,the relative amount of 6-chloropurine,4-amino-pyridine and triethylamine in the system had a great influence on the reaction,and the highest catalytic activity was achieved using a mixture of 4-amino-pyridine and triethylamine as the catalyst.
A series of O6-substituted purine derivatives was designed and prepared through an efficient and convenient method with 4-amino-pyridine as the catalyst in methanol solvent.Under optimized conditions:n(6-chloropurine):n(4-amino-pyridine):n(triethylamine)=10:1:4,refluxing for 5~7 h,the yield of 6-alkoxy purine was greater than 85%.Studies showed that,the relative amount of 6-chloropurine,4-amino-pyridine and triethylamine in the system had a great influence on the reaction,and the highest catalytic activity was achieved using a mixture of 4-amino-pyridine and triethylamine as the catalyst.
2012, 29(4): 410-415
doi: 10.3724/SP.J.1095.2012.00248
Abstract:
β-CD-mono-6-(N-aminoethyl)-3-aminopropyltrimethoxy silane was synthesized and used together with 1,2-bis(triethoxysilyl)-ethane(BTEE) as silica resources templated by cetyltriethyl-ammnonium bromide(CTAB) for preparing mesoporous chiral materials via hydrothermal processes.After phenylcarbamated with phenyl isocyanate an organo-inorganic chiral silica composite(β-CD PMOs) was obtained,in which β-CD was incorporated to the wall of the channels while ethyl groups were located in the framework.The periodic mesporous organosilicas(PMOs) was utilized as chiral stationary phase(CSP) for enantioseparartion of some alkaline medicines containing nitrogen under reverse-phase high-performance liquid chromatography(RP-HPLC) and normal-phase high-performance liquid chromatography(NP-HPLC) conditions.The results showed that the enantioseparartion of these medicines could be effectively achieved by β-CD PMOs using common mobile phases at the similar pH value(pH=4.15).The maximal enantioseparartion selectivity factor(α) was 2.42.In addition,excellent permeability and reproducibility facilitate the establishment of a new enantioseparation method for chiral medicines.The chromatographic data indicated that β-CD PMOs are promising for the enantioseparation of medicines.
β-CD-mono-6-(N-aminoethyl)-3-aminopropyltrimethoxy silane was synthesized and used together with 1,2-bis(triethoxysilyl)-ethane(BTEE) as silica resources templated by cetyltriethyl-ammnonium bromide(CTAB) for preparing mesoporous chiral materials via hydrothermal processes.After phenylcarbamated with phenyl isocyanate an organo-inorganic chiral silica composite(β-CD PMOs) was obtained,in which β-CD was incorporated to the wall of the channels while ethyl groups were located in the framework.The periodic mesporous organosilicas(PMOs) was utilized as chiral stationary phase(CSP) for enantioseparartion of some alkaline medicines containing nitrogen under reverse-phase high-performance liquid chromatography(RP-HPLC) and normal-phase high-performance liquid chromatography(NP-HPLC) conditions.The results showed that the enantioseparartion of these medicines could be effectively achieved by β-CD PMOs using common mobile phases at the similar pH value(pH=4.15).The maximal enantioseparartion selectivity factor(α) was 2.42.In addition,excellent permeability and reproducibility facilitate the establishment of a new enantioseparation method for chiral medicines.The chromatographic data indicated that β-CD PMOs are promising for the enantioseparation of medicines.
2012, 29(4): 416-421
doi: 10.3724/SP.J.1095.2012.00241
Abstract:
The inhibitive role of lanthanum ion on the arginase catalyzed hydrolysis of L-arginine was studied by microcalorimetry in a 40 mmol/L sodium barbiturate-hydrochloric acid buffer solution at 37℃ and pH of 9.4.The results indicated La3+ has remarkable inhibition effect on the catalytic activity of arginase and the inhibitory type belongs to the reversible non-competitive inhibition with the inhibition constant of 2.74×10-4 mol/L. On the basis of the inhibition type and ion radius,we suggested that the binding site of La3+ to arginase is far from the active site of arginase.
The inhibitive role of lanthanum ion on the arginase catalyzed hydrolysis of L-arginine was studied by microcalorimetry in a 40 mmol/L sodium barbiturate-hydrochloric acid buffer solution at 37℃ and pH of 9.4.The results indicated La3+ has remarkable inhibition effect on the catalytic activity of arginase and the inhibitory type belongs to the reversible non-competitive inhibition with the inhibition constant of 2.74×10-4 mol/L. On the basis of the inhibition type and ion radius,we suggested that the binding site of La3+ to arginase is far from the active site of arginase.
2012, 29(4): 422-427
doi: 10.3724/SP.J.1095.2012.00198
Abstract:
The growth and metabolism of Bacillus subtilis 63501 were investigated under low direct current(DC) electric filed.The effects of the electric filed on the growth,pH values,ATPase activity,total amount of protein and cells membrane penetration of Bacillus subtilis 63501 solutions were studied.The surface morphologies of the bacteria were also characterized by transimission electronic microscopy(TEM).The results indicated that the growth of such bacteria could be enhanced under an appropriate DC electric field.The ATPase activity of Bacillus subtilis 63501 could be multiplied by 1.9,3.5 and 3.8 times during the control in prophase,anaphase and stable phase under 0.0455×10-3 A/cm2 current density,suggesting that suitable direct current density can promote the metabolism activity of Bacillus subtilis 63501,which is consistent with the results form TEM observations.
The growth and metabolism of Bacillus subtilis 63501 were investigated under low direct current(DC) electric filed.The effects of the electric filed on the growth,pH values,ATPase activity,total amount of protein and cells membrane penetration of Bacillus subtilis 63501 solutions were studied.The surface morphologies of the bacteria were also characterized by transimission electronic microscopy(TEM).The results indicated that the growth of such bacteria could be enhanced under an appropriate DC electric field.The ATPase activity of Bacillus subtilis 63501 could be multiplied by 1.9,3.5 and 3.8 times during the control in prophase,anaphase and stable phase under 0.0455×10-3 A/cm2 current density,suggesting that suitable direct current density can promote the metabolism activity of Bacillus subtilis 63501,which is consistent with the results form TEM observations.
2012, 29(4): 428-433
doi: 10.3724/SP.J.1095.2012.00262
Abstract:
Stability dynamic characteristics of alkali/surfactant/polymer(ASP) flooding crude oil emulsion was studied using emulsion stability model based on two-phase separation.Effect of alkali/surfactant/polymer on dynamic characteristics of ASP flooding crude oil emulsion was also studied by analyzing oil film strength qualitatively and measuring oil-water interfacial tension.The results showed that Civan model was suitable to evaluate the stability of ASP flooding crude oil emulsion and thus the stability dynamic characteristics were obtained.The crude oil emulsions became more stable with the increase of alkali concentration firstly at low alkali concentration(<900 mg/L) and then less stable with the increasing alkali concentration at high alkali concentration(>900 mg/L).The stabilities of crude oil emulsions were improved with the increase of the concentrations of surfactant and polymer.The stability mechanism of ASP flooding W/O emulsion could be ascribed to the decrease of oil-water interfacial tensions when alkali and surfactant were used and increase of the oil-water interfacial strength when the polymer was added to the system.Therefore alkali,surfactant and polymer have synergistic effect.
Stability dynamic characteristics of alkali/surfactant/polymer(ASP) flooding crude oil emulsion was studied using emulsion stability model based on two-phase separation.Effect of alkali/surfactant/polymer on dynamic characteristics of ASP flooding crude oil emulsion was also studied by analyzing oil film strength qualitatively and measuring oil-water interfacial tension.The results showed that Civan model was suitable to evaluate the stability of ASP flooding crude oil emulsion and thus the stability dynamic characteristics were obtained.The crude oil emulsions became more stable with the increase of alkali concentration firstly at low alkali concentration(<900 mg/L) and then less stable with the increasing alkali concentration at high alkali concentration(>900 mg/L).The stabilities of crude oil emulsions were improved with the increase of the concentrations of surfactant and polymer.The stability mechanism of ASP flooding W/O emulsion could be ascribed to the decrease of oil-water interfacial tensions when alkali and surfactant were used and increase of the oil-water interfacial strength when the polymer was added to the system.Therefore alkali,surfactant and polymer have synergistic effect.
2012, 29(4): 434-439
doi: 10.3724/SP.J.1095.2012.00247
Abstract:
The methyl oleate emulsion was prepared using alkylethoxyglucoside(AEG) surfactant and bentonite nanoparticles(NPT-2) as emulsifiers.The effects of the ratio of AEG to NPT-2 on the stability and diameter of the emulsive droplet were discussed in detail.The synergetic stability mechanism of the two compounds was investigated by means of surface tension and zeta potential measurement.The results showed that methyl oleate emulsion couldn't be stabled by either alkylethoxyglucoside(AEG) or bentonite nanoparticles(NPT-2) alone.At fixed amount of AEG,the diameter of the emulsive droplet increased first and then decreased with increasing NPT-2.However,at fixed the amount of NPT-2,the diameter of the emulsive droplet decreased as increasing the amount of AEG.The "lag" of the surface tension curve and the increased value of the zeta potential indicated that the molecules of AEG were adsorbed onto the NPT-2 nanoparticles to stabilize the emusion synergetically.
The methyl oleate emulsion was prepared using alkylethoxyglucoside(AEG) surfactant and bentonite nanoparticles(NPT-2) as emulsifiers.The effects of the ratio of AEG to NPT-2 on the stability and diameter of the emulsive droplet were discussed in detail.The synergetic stability mechanism of the two compounds was investigated by means of surface tension and zeta potential measurement.The results showed that methyl oleate emulsion couldn't be stabled by either alkylethoxyglucoside(AEG) or bentonite nanoparticles(NPT-2) alone.At fixed amount of AEG,the diameter of the emulsive droplet increased first and then decreased with increasing NPT-2.However,at fixed the amount of NPT-2,the diameter of the emulsive droplet decreased as increasing the amount of AEG.The "lag" of the surface tension curve and the increased value of the zeta potential indicated that the molecules of AEG were adsorbed onto the NPT-2 nanoparticles to stabilize the emusion synergetically.
2012, 29(4): 440-445
doi: 10.3724/SP.J.1095.2012.00222
Abstract:
In pH=5.4 Britton-Robinson(BR) buffer solution,fenaminosulf(FM) reacted with acriflavine(AF) to form an ion associated complex,which resulted in the quench of the fluorescences of acriflavine.The maximum excitation wavelength(λex) and emission wavelength(λem) was located at 451 nm and 508 nm.The quenching value(ΔF) was linear to the concentration of FM in the range of 0.16~5.0 mg/L with the detection of limit(3σ) of 0.048 mg/L.Therefore,a simple,rapid,highly sensitive and selective method for the determination of FM by fluorescence quenching had been established.The proposed method had been used to determine FM in fenaminosulf pesticide and soil residue with satisfactory results.In addition,the fluorescence characters of the reaction system and the mechanism of fluorescence quenching were also discussed by AM1 calculations.
In pH=5.4 Britton-Robinson(BR) buffer solution,fenaminosulf(FM) reacted with acriflavine(AF) to form an ion associated complex,which resulted in the quench of the fluorescences of acriflavine.The maximum excitation wavelength(λex) and emission wavelength(λem) was located at 451 nm and 508 nm.The quenching value(ΔF) was linear to the concentration of FM in the range of 0.16~5.0 mg/L with the detection of limit(3σ) of 0.048 mg/L.Therefore,a simple,rapid,highly sensitive and selective method for the determination of FM by fluorescence quenching had been established.The proposed method had been used to determine FM in fenaminosulf pesticide and soil residue with satisfactory results.In addition,the fluorescence characters of the reaction system and the mechanism of fluorescence quenching were also discussed by AM1 calculations.
2012, 29(4): 446-454
doi: 10.3724/SP.J.1095.2012.00305
Abstract:
In HAc-NaAc buffer medium with pH=5.37~5.58,6-benzylaminopurine(6-BA) reacted with Cu(Ⅱ) to form a chelate[6-BA·Cu]2+,which further reacted with triphenylmethane dyes to form 2:1(Lissamine green system),3:1(fast green system) and 2.5:1(water-soluble aniline blue system) ternary ion-associations,respectively.It resulted in the change of the absorption spectra,the great enhancement of resonance Rayleigh scattering(RRS) spectra and frequency doubling scattering(FDS) intensities.The maximum RRS wavelengths were all located at 372 nm.And the increased amount of absorption,the enhancement degree of RRS(ΔIRRS),FDS(ΔIFDS) were all proportional to the concentration of 6-BA during a certain range.The detection limits of methods for Lissamine green system were 5.48 μg/L,119.70 μg/L and 64.20 μg/L,respectively.Therefore,a sensitive method for determination of trace 6-BA with RRS spectrum in 6-BA-Cu(Ⅱ)-LG system has been developed.The method could be applied to the determination of 6-BA in bean sprouts with satisfactory results.In this paper,we used Gaussview 3.07 and Gaussian 03W softwares at a B3LYP/6-31G(base group) level based on the density functional theory(DFT) to calculate the charge distribution of 6-BA.Furthermore,the reaction mechanism and the main reasons for the enhancement of RRS of the Lissamine green system were preliminarily discussed.
In HAc-NaAc buffer medium with pH=5.37~5.58,6-benzylaminopurine(6-BA) reacted with Cu(Ⅱ) to form a chelate[6-BA·Cu]2+,which further reacted with triphenylmethane dyes to form 2:1(Lissamine green system),3:1(fast green system) and 2.5:1(water-soluble aniline blue system) ternary ion-associations,respectively.It resulted in the change of the absorption spectra,the great enhancement of resonance Rayleigh scattering(RRS) spectra and frequency doubling scattering(FDS) intensities.The maximum RRS wavelengths were all located at 372 nm.And the increased amount of absorption,the enhancement degree of RRS(ΔIRRS),FDS(ΔIFDS) were all proportional to the concentration of 6-BA during a certain range.The detection limits of methods for Lissamine green system were 5.48 μg/L,119.70 μg/L and 64.20 μg/L,respectively.Therefore,a sensitive method for determination of trace 6-BA with RRS spectrum in 6-BA-Cu(Ⅱ)-LG system has been developed.The method could be applied to the determination of 6-BA in bean sprouts with satisfactory results.In this paper,we used Gaussview 3.07 and Gaussian 03W softwares at a B3LYP/6-31G(base group) level based on the density functional theory(DFT) to calculate the charge distribution of 6-BA.Furthermore,the reaction mechanism and the main reasons for the enhancement of RRS of the Lissamine green system were preliminarily discussed.
2012, 29(4): 455-461
doi: 10.3724/SP.J.1095.2012.00231
Abstract:
The cefazolin can be detected according to the change of solution color resulting from the plasmonic resonance absorption of AuNPs.The absorbance ratio at 520/660 nm of AuNPs is proportional to the concentration of cefazolin in the range of 0.1~5.0 μmol/L with the detection limit of 14 nmol/L.This method could be extended to the determination of cefazolin sodium powder injection,the recovery of cefazolin was in the range of 97.4%~100.2% while the relative standard deviation was less than 6.1%.
The cefazolin can be detected according to the change of solution color resulting from the plasmonic resonance absorption of AuNPs.The absorbance ratio at 520/660 nm of AuNPs is proportional to the concentration of cefazolin in the range of 0.1~5.0 μmol/L with the detection limit of 14 nmol/L.This method could be extended to the determination of cefazolin sodium powder injection,the recovery of cefazolin was in the range of 97.4%~100.2% while the relative standard deviation was less than 6.1%.
2012, 29(4): 462-469
doi: 10.3724/SP.J.1095.2012.00260
Abstract:
The matrix for laccase immobilization consisting of chitosan-g-N-carboxymethyl-2-sulfo-4,5-2H imidazolinone(CTS-g-N-CSIDZ) and multiwall carbon nanotubes(MWCNTs) was prepared through MWCNTs non-covalently functionalized with CTS-g-N-CSIDZ.Laccase immobilization on the composite carrier was achieved mainly by physical adsorption together with active centers in laccase complexing with ligands on the carrier and therefore the immobilized laccase could retain its original conformation of active centre to a great extent.On the glassy carbon electrode modified by the composite with adsorbed laccase was fabricated by a layer of composite composed with entrapped laccase attached to the surface of bare electrode.On the basis of determinoffing the loading of the composite matrix towards laccase,specific activity of immobilized laccase,stability,reusability and catalytic 2,6-dimethoxyphenol(DMP) oxidization dynamic parameters of the immobilized laccase on the composite matrix,function of this chemical sensor based on the electrode modified with the composite which accommodated laccase were examined(DMP as substrate).Results indicated this composite matrix for laccase entrapment had superiority of high enzyme loading amount(81.7 mg/g),improved laccase specific activity in immobilized state(1.33 U/mg).While the entrapped laccase in composite modified electrode as electrochemical sensor showed favorable affinity towards its substrate:DMP(Michaelis-Menten constant KM is 0.0918 mmol/L),relatively higher sensitivity to DMP(3680 mA·L/mol),lower detection limit for DMP(3.3×10-4 mmol/L),its relatively higher responsible selectivity,favorable reproducibility,reusability and excellent long-term stability were obtained.Such advantages make this laccase-based electrode one of promising candidates as amperometric electrochemical sensor for application in sensing the specific phenol-like compound selectively.
The matrix for laccase immobilization consisting of chitosan-g-N-carboxymethyl-2-sulfo-4,5-2H imidazolinone(CTS-g-N-CSIDZ) and multiwall carbon nanotubes(MWCNTs) was prepared through MWCNTs non-covalently functionalized with CTS-g-N-CSIDZ.Laccase immobilization on the composite carrier was achieved mainly by physical adsorption together with active centers in laccase complexing with ligands on the carrier and therefore the immobilized laccase could retain its original conformation of active centre to a great extent.On the glassy carbon electrode modified by the composite with adsorbed laccase was fabricated by a layer of composite composed with entrapped laccase attached to the surface of bare electrode.On the basis of determinoffing the loading of the composite matrix towards laccase,specific activity of immobilized laccase,stability,reusability and catalytic 2,6-dimethoxyphenol(DMP) oxidization dynamic parameters of the immobilized laccase on the composite matrix,function of this chemical sensor based on the electrode modified with the composite which accommodated laccase were examined(DMP as substrate).Results indicated this composite matrix for laccase entrapment had superiority of high enzyme loading amount(81.7 mg/g),improved laccase specific activity in immobilized state(1.33 U/mg).While the entrapped laccase in composite modified electrode as electrochemical sensor showed favorable affinity towards its substrate:DMP(Michaelis-Menten constant KM is 0.0918 mmol/L),relatively higher sensitivity to DMP(3680 mA·L/mol),lower detection limit for DMP(3.3×10-4 mmol/L),its relatively higher responsible selectivity,favorable reproducibility,reusability and excellent long-term stability were obtained.Such advantages make this laccase-based electrode one of promising candidates as amperometric electrochemical sensor for application in sensing the specific phenol-like compound selectively.
2012, 29(4): 470-476
doi: 10.3724/SP.J.1095.2012.00238
Abstract:
The volatile oil components from Atractylodes chinensis(DC.) Koidz.and Atractylodes lancea(Thunb.) DC.were analyzed by GC-MS.Forty-seven and fifty components were identified,respectively,and their relative contents were determined.The volatile oil components from Atractylodes chinensis(DC.) Koidz.and Atractylodes lancea(Thunb.) DC.were further compared with each other by using the Eight Strong Peaks and Dividing Sections of the chromatographic fingerprint methods.The total ionic current chromatograms were divided into five fingerprint sections on the basis of peak retention time.The results showed that the major active components of Rhizoma Atractylodis are β-eudesmol,atractylon and atractylodin and they were identified with higher relative content in the Ⅳ and Ⅴ sections of the total ionic current chromatograms,suggesting that it was acceptable to combine Atractylodes chinensis(DC.) Koidz.and Atractylodes lancea(Thunb.) DC together as Rhizoma Atractylodis in the Pharmacopoeia of the People's Republic of China.
The volatile oil components from Atractylodes chinensis(DC.) Koidz.and Atractylodes lancea(Thunb.) DC.were analyzed by GC-MS.Forty-seven and fifty components were identified,respectively,and their relative contents were determined.The volatile oil components from Atractylodes chinensis(DC.) Koidz.and Atractylodes lancea(Thunb.) DC.were further compared with each other by using the Eight Strong Peaks and Dividing Sections of the chromatographic fingerprint methods.The total ionic current chromatograms were divided into five fingerprint sections on the basis of peak retention time.The results showed that the major active components of Rhizoma Atractylodis are β-eudesmol,atractylon and atractylodin and they were identified with higher relative content in the Ⅳ and Ⅴ sections of the total ionic current chromatograms,suggesting that it was acceptable to combine Atractylodes chinensis(DC.) Koidz.and Atractylodes lancea(Thunb.) DC together as Rhizoma Atractylodis in the Pharmacopoeia of the People's Republic of China.
2012, 29(4): 477-482
doi: 10.3724/SP.J.1095.2012.00139
Abstract:
To identify and analyze puffballs from Inner Mongolia and Jilin in situ,the SEM,FTIR and pyrolysis gas chromatography mass spectrometry(Py-GCMS) were used for the analysis of the microstructure,elemental composition,main category and chemical composition of small molecules,etc.The SEM results indicated that puffball from Inner Mongolia was Mycenastrum corium(guers.) Desv but from Jilin was Bovistella radicata(Mont.) Pat.The FTIR spectra showed that the absorptions of amide I bands of proteins of puffball from Inner Mongolia and Jilin were at 1636 cm-1 and 1654 cm-1,respectively.The second derivative FTIR spectrum of puffball from Jilin had stronger absorption at 1625 cm-1 suggesting that it contained more aromatic compounds,which was in accordance with the results of Py-GCMS that the contents of phenol and p-methylphenol from Jilin were apparently higher than those from Inner Mongolia.In addition,the Py-GCMS results showed the differences in the pyrolysis compositions and contents between two places of origin of puffballs.
To identify and analyze puffballs from Inner Mongolia and Jilin in situ,the SEM,FTIR and pyrolysis gas chromatography mass spectrometry(Py-GCMS) were used for the analysis of the microstructure,elemental composition,main category and chemical composition of small molecules,etc.The SEM results indicated that puffball from Inner Mongolia was Mycenastrum corium(guers.) Desv but from Jilin was Bovistella radicata(Mont.) Pat.The FTIR spectra showed that the absorptions of amide I bands of proteins of puffball from Inner Mongolia and Jilin were at 1636 cm-1 and 1654 cm-1,respectively.The second derivative FTIR spectrum of puffball from Jilin had stronger absorption at 1625 cm-1 suggesting that it contained more aromatic compounds,which was in accordance with the results of Py-GCMS that the contents of phenol and p-methylphenol from Jilin were apparently higher than those from Inner Mongolia.In addition,the Py-GCMS results showed the differences in the pyrolysis compositions and contents between two places of origin of puffballs.
2012, 29(4): 483-485
doi: 10.3724/SP.J.1095.2012.00253
Abstract:
Firstly,3,4,5,6,7-penta-O-benzyl-D-manno-hept-1-enitol was prepared from 2,3,4,5,6-penta-O-benzyl-D-mannose via Wittig reaction(yield 88%).The olefinated sugar was dihudroxylated to yield 3,4,5,6,7-penta-O-benzyl-D-mannoheptol(yield 65%) with the presence of phenyliodine(Ⅲ) diacetate(PIDA)/LiBr.Finally,D-mannoheptol was synthesized through debenzylation(yield 90%).The overall yield was about 51%.The method had the advantages of convenience and environmental friendly,which provided a new approach for the synthesis of such rare alditol.
Firstly,3,4,5,6,7-penta-O-benzyl-D-manno-hept-1-enitol was prepared from 2,3,4,5,6-penta-O-benzyl-D-mannose via Wittig reaction(yield 88%).The olefinated sugar was dihudroxylated to yield 3,4,5,6,7-penta-O-benzyl-D-mannoheptol(yield 65%) with the presence of phenyliodine(Ⅲ) diacetate(PIDA)/LiBr.Finally,D-mannoheptol was synthesized through debenzylation(yield 90%).The overall yield was about 51%.The method had the advantages of convenience and environmental friendly,which provided a new approach for the synthesis of such rare alditol.
2012, 29(4): 486-488
doi: 10.3724/SP.J.1095.2012.00265
Abstract:
Using natural rosin as raw material,maleic rosin-nitrile,a new rosin derivative,was synthesized via ammoniation,dehydration and Diels-Alder reaction.The effects of reaction temperature,reaction time,material ratio on yield were investigated.The synthetic conditions were optimized.The structure of maleic rosin-nitrile was identified by means of IR,1H NMR and MS.
Using natural rosin as raw material,maleic rosin-nitrile,a new rosin derivative,was synthesized via ammoniation,dehydration and Diels-Alder reaction.The effects of reaction temperature,reaction time,material ratio on yield were investigated.The synthetic conditions were optimized.The structure of maleic rosin-nitrile was identified by means of IR,1H NMR and MS.
