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2007 Volume 24 Issue 5
2007, 24(5): 489-493
Abstract:
4-[Trans-4'-(trans-4"-n-alkylcyclohexyl) cyclohexyl]bromobenzene (5) was synthesized with trans-4-(4'-n-alkylcyclohexyl) cyclohexanone and bromobenzene as the starting materials via Grignard reaction,dehydroxylation,catalytic hydrogenation,configuration translation and bromination.Six biaryl type liquid crystal compounds containing fluorine were synthesized by Suzuki coupling reaction between compound 5 and phenylboronic acid containing fluorine catalyzed by Pd(Ph2PCH2COO)2.The total yields of the six biaryl type liquid crystal compounds containing fluorine after purification based on trans-4-(4'-n-alkylcyclohexyl) cyclohexanone were all ca.50%.In the process of synthesizing 4-(trans-4'-n-alkylcyclohexyl) cyclohexyl bezene,the cyclohexane intermediate was isomerized in DMF-t-Buok medium with the yield of 82%,much higher than expected (50%).The catalytic mechanism of the cis-trans cyclohexyl isomerization was discussed.The data of GC-MS and 1H NMR proved that the target compounds were obtained indeed.The results of DSC show that these liquid crystal compounds exhibit a broad temperature range of mesomorphic phases and high clear points.
4-[Trans-4'-(trans-4"-n-alkylcyclohexyl) cyclohexyl]bromobenzene (5) was synthesized with trans-4-(4'-n-alkylcyclohexyl) cyclohexanone and bromobenzene as the starting materials via Grignard reaction,dehydroxylation,catalytic hydrogenation,configuration translation and bromination.Six biaryl type liquid crystal compounds containing fluorine were synthesized by Suzuki coupling reaction between compound 5 and phenylboronic acid containing fluorine catalyzed by Pd(Ph2PCH2COO)2.The total yields of the six biaryl type liquid crystal compounds containing fluorine after purification based on trans-4-(4'-n-alkylcyclohexyl) cyclohexanone were all ca.50%.In the process of synthesizing 4-(trans-4'-n-alkylcyclohexyl) cyclohexyl bezene,the cyclohexane intermediate was isomerized in DMF-t-Buok medium with the yield of 82%,much higher than expected (50%).The catalytic mechanism of the cis-trans cyclohexyl isomerization was discussed.The data of GC-MS and 1H NMR proved that the target compounds were obtained indeed.The results of DSC show that these liquid crystal compounds exhibit a broad temperature range of mesomorphic phases and high clear points.
2007, 24(5): 494-498
Abstract:
In saturated Ca(OH)2 solutions,CaMoO4 thin films with scheelite structure were prepared by potentiostatic anode oxidation method.The influence of solution acidity and the method of substrate pretreatment on the film growth as well as the change of current during the deposition were studied,and the crystal phase structure,surface morphology,chemical compositions as well as photoluminescence at room temperature were investigated by XRD,SEM,XPS and FA (fluorescence analysis),respectively.The results revealed that the grain growth was more complete for the CaMoO4 films deposited on polished substrate,and the grain size was larger and the photoluminescence at room temperature better than that of CaMoO4 films deposited on the substrate etched by mixture acids.When the solution pH exceeded 12.30,cluster growth of the grains was observed.Therefore,it is better to prepare CaMoO4 films by potentiostatic anode oxidation method on polished substrate,and to control the solution pH at about 12.00.
In saturated Ca(OH)2 solutions,CaMoO4 thin films with scheelite structure were prepared by potentiostatic anode oxidation method.The influence of solution acidity and the method of substrate pretreatment on the film growth as well as the change of current during the deposition were studied,and the crystal phase structure,surface morphology,chemical compositions as well as photoluminescence at room temperature were investigated by XRD,SEM,XPS and FA (fluorescence analysis),respectively.The results revealed that the grain growth was more complete for the CaMoO4 films deposited on polished substrate,and the grain size was larger and the photoluminescence at room temperature better than that of CaMoO4 films deposited on the substrate etched by mixture acids.When the solution pH exceeded 12.30,cluster growth of the grains was observed.Therefore,it is better to prepare CaMoO4 films by potentiostatic anode oxidation method on polished substrate,and to control the solution pH at about 12.00.
2007, 24(5): 499-502
Abstract:
The title compounds were designed and synthesized by condensation of the intermediate of pyridinylthiadiazolyl-thiol 3 with various halides to pyridyl-substituted thiadiazole sulfanylethers (4a~4e),followed by the quaternization of compounds 4a~4e with methyl iodide to afford the corresponding methylpyridiniun salts (5a~5e),and reduction of compounds 5a~e with sodium borohydride to give a series of the corresponding target compounds 6a~6e containing the thiadiazole sulfanylether moiety at the 3-position of tetrahydropyridine ring.The structures of the synthesized compounds were characterized by IR,1H NMR,MS spectra and element analysis.The in vitro vascular relaxing activity of target compounds 6a~6e were screened at the concentration 10 μmol/L,their vascular relaxing effects on isolated endothelial cells are 22%,32%,40%,46% and 8%,respectively,while arecoline as reference drug was 21% at the same conditions.
The title compounds were designed and synthesized by condensation of the intermediate of pyridinylthiadiazolyl-thiol 3 with various halides to pyridyl-substituted thiadiazole sulfanylethers (4a~4e),followed by the quaternization of compounds 4a~4e with methyl iodide to afford the corresponding methylpyridiniun salts (5a~5e),and reduction of compounds 5a~e with sodium borohydride to give a series of the corresponding target compounds 6a~6e containing the thiadiazole sulfanylether moiety at the 3-position of tetrahydropyridine ring.The structures of the synthesized compounds were characterized by IR,1H NMR,MS spectra and element analysis.The in vitro vascular relaxing activity of target compounds 6a~6e were screened at the concentration 10 μmol/L,their vascular relaxing effects on isolated endothelial cells are 22%,32%,40%,46% and 8%,respectively,while arecoline as reference drug was 21% at the same conditions.
2007, 24(5): 503-506
Abstract:
Nanocrystalline nickel with an average diameter of about 16 nm and a face-centered cubic (fcc) structure were uniformly attached to the surface of multi-wall carbon nanotubes by wet chemistry,and the product was characterized by X-ray power diffraction and transmission electron microscopy.A glass carbon electrode modified with the nickel-decorated carbon nanotubes (MWCNTs-Ni/GCE) was prepared.The electrochemical behavior of the MWCNTs-Ni/GCE and the electrocatalytic oxidation of methanol at the MWCNTs-Ni/GCE were investigated by means of cyclic voltammetry in 1.0 mol/L NaOH solution.The cyclic voltammetry showed the electron transfer of β-Ni(OH)2⇋β-NiOOH is mainly a diffusion-controlled quasi-reversible process,and the high catalytic activity of the electrode for the electro-oxidation of methanol in alkaline medium suggests its potential application in alkaline rechargeable batteries and fuel cells.
Nanocrystalline nickel with an average diameter of about 16 nm and a face-centered cubic (fcc) structure were uniformly attached to the surface of multi-wall carbon nanotubes by wet chemistry,and the product was characterized by X-ray power diffraction and transmission electron microscopy.A glass carbon electrode modified with the nickel-decorated carbon nanotubes (MWCNTs-Ni/GCE) was prepared.The electrochemical behavior of the MWCNTs-Ni/GCE and the electrocatalytic oxidation of methanol at the MWCNTs-Ni/GCE were investigated by means of cyclic voltammetry in 1.0 mol/L NaOH solution.The cyclic voltammetry showed the electron transfer of β-Ni(OH)2⇋β-NiOOH is mainly a diffusion-controlled quasi-reversible process,and the high catalytic activity of the electrode for the electro-oxidation of methanol in alkaline medium suggests its potential application in alkaline rechargeable batteries and fuel cells.
2007, 24(5): 507-511
Abstract:
Four Benzimidazole ferrocenesulfonyl derivatives were prepared by the reaction of ferrocenesulfonylchloride with the corresponding benzimidazoles under microwave irradiation.The compounds were characte-rized by means of elemental analysis,MS and 1H NMR.Henna prismatic crystals of compound 4b were obtained,and the crystal structure was determined by virtue of X-ray diffraction.The crystal is monoclinic with space group P2(1)/c,and the unit cell parameters are a=0.983 45(6) nm,b=1.702 37(11) nm,c=1.180 96(7) nm,α=90°,β=100.998(4)°,γ=90°,V=1.144 3(2) nm3,Z=4,F(000)=1 744,Mr=443.30,Dc=1.517 g/cm3,R1=0.098 3,wR2=0.110 1.The preliminary bioassay results indicate that compounds 4a~4d have antimicrobial activity to a certain degree.Compound 4d shows excellent activities against 5 kinds of tested fungus at EC50 17.12~37.11 mg/L.
Four Benzimidazole ferrocenesulfonyl derivatives were prepared by the reaction of ferrocenesulfonylchloride with the corresponding benzimidazoles under microwave irradiation.The compounds were characte-rized by means of elemental analysis,MS and 1H NMR.Henna prismatic crystals of compound 4b were obtained,and the crystal structure was determined by virtue of X-ray diffraction.The crystal is monoclinic with space group P2(1)/c,and the unit cell parameters are a=0.983 45(6) nm,b=1.702 37(11) nm,c=1.180 96(7) nm,α=90°,β=100.998(4)°,γ=90°,V=1.144 3(2) nm3,Z=4,F(000)=1 744,Mr=443.30,Dc=1.517 g/cm3,R1=0.098 3,wR2=0.110 1.The preliminary bioassay results indicate that compounds 4a~4d have antimicrobial activity to a certain degree.Compound 4d shows excellent activities against 5 kinds of tested fungus at EC50 17.12~37.11 mg/L.
2007, 24(5): 512-516
Abstract:
Lightly oxidized porous silicon was prepared by anodizing p-type single crystal silicon and photochemically oxidizing porous silicon.By means of SEM,AFM,FT-IR,the structure and morphology of the porous silicon was analyzed.The sensing performance was studied quantitatively by photoluminescence quenching of porous silicon.The results showed the structure of freshly etched porous silicon was very unstable because the silicon hydride (Si-Hx) on the porous silicon surface reacted with the ambient air easily.SEM images showed that the surface of the fresh porous silicon was covered by a lot of 120×40 μm rectangle pieces.After being oxidized by photochemical method,these rectangle pieces beceme smaller.AFM images indicated the porous silicon was covered by some porous silicon columns,and after being oxidized by photochemical method,the height of the columns decreased from 700~750 nm to 300~350 nm,and the thickness of the porous film was cut down from 50~58 nm to 40 nm;and partial Si-Hx band was replaced by Si-O band at around 1 114 cm-1 and OSi-H band at around 2 249 cm-1.The sensing experiment showed the photoluminescence of the stabilized porous silicon could be reversibly quenched by sulfur dioxide of different concentrations of,and the corresponding peak wavelength was not changed.
Lightly oxidized porous silicon was prepared by anodizing p-type single crystal silicon and photochemically oxidizing porous silicon.By means of SEM,AFM,FT-IR,the structure and morphology of the porous silicon was analyzed.The sensing performance was studied quantitatively by photoluminescence quenching of porous silicon.The results showed the structure of freshly etched porous silicon was very unstable because the silicon hydride (Si-Hx) on the porous silicon surface reacted with the ambient air easily.SEM images showed that the surface of the fresh porous silicon was covered by a lot of 120×40 μm rectangle pieces.After being oxidized by photochemical method,these rectangle pieces beceme smaller.AFM images indicated the porous silicon was covered by some porous silicon columns,and after being oxidized by photochemical method,the height of the columns decreased from 700~750 nm to 300~350 nm,and the thickness of the porous film was cut down from 50~58 nm to 40 nm;and partial Si-Hx band was replaced by Si-O band at around 1 114 cm-1 and OSi-H band at around 2 249 cm-1.The sensing experiment showed the photoluminescence of the stabilized porous silicon could be reversibly quenched by sulfur dioxide of different concentrations of,and the corresponding peak wavelength was not changed.
2007, 24(5): 517-520
Abstract:
Amorphous Mg0.9Ti0.1Ni0.85Co0.15 alloy was coated with graphite and nickel powder by ball milling.SEM indicated that there was a graphite or nickel thin layer on the surface of the alloy.X-ray energy spectrum analysis showed that after coated with graphite powder,the C content at the surface of the alloy increased,and the mass and atomic contents of Mg decreased from 22.74% to 22.23%,and from 36.43% to 32.94%,respectively,which decreased the corrosion probability of Mg in alkali solution;after coated with nickel powder,the mass and atomic contents of Ni at the surface of the alloy increased from 59.89% to 60.04%,and from 40.63% to 41.02%,respectively,which indicted that a nickel-riched layer was formed.This nickel-riched layer can protect the alloy from corrosion in alkali solution.Charge-discharge cycle tests showed that after 30 charge-discharge cycles,the capacity retained for the graphite coated alloy,the nickel coated alloy,and the uncoated alloy was 32.05%,41.26% and 17.88%,respectively.This indicates the graphite coating and the nickel powder coating can increase the cycle stability.Polarization curves showed the antico-rrosion characteristic of the Mg0.9Ti0.1Ni0.85Co0.15 alloy electrode in KOH solution was improved by graphite or nickel coated.
Amorphous Mg0.9Ti0.1Ni0.85Co0.15 alloy was coated with graphite and nickel powder by ball milling.SEM indicated that there was a graphite or nickel thin layer on the surface of the alloy.X-ray energy spectrum analysis showed that after coated with graphite powder,the C content at the surface of the alloy increased,and the mass and atomic contents of Mg decreased from 22.74% to 22.23%,and from 36.43% to 32.94%,respectively,which decreased the corrosion probability of Mg in alkali solution;after coated with nickel powder,the mass and atomic contents of Ni at the surface of the alloy increased from 59.89% to 60.04%,and from 40.63% to 41.02%,respectively,which indicted that a nickel-riched layer was formed.This nickel-riched layer can protect the alloy from corrosion in alkali solution.Charge-discharge cycle tests showed that after 30 charge-discharge cycles,the capacity retained for the graphite coated alloy,the nickel coated alloy,and the uncoated alloy was 32.05%,41.26% and 17.88%,respectively.This indicates the graphite coating and the nickel powder coating can increase the cycle stability.Polarization curves showed the antico-rrosion characteristic of the Mg0.9Ti0.1Ni0.85Co0.15 alloy electrode in KOH solution was improved by graphite or nickel coated.
2007, 24(5): 521-524
Abstract:
To improve the synthetic method of 13-cis-retinoic acid derivatives,the title compounds were synthesized directly from 13-cis-retinoic acid and alcohols,phenols or amines with DCC as the condensation reagent under the catalysis of 4-(dimethylamino) pyridinium p-toluenesulfonate prepared in our lab.Eight new compounds were obtained in 80%~95% yields and in a high isomeric purity,which were characterized by NMR.The side reaction that converts 13-cis-retinoic acid to unreactive N-retinoylurea was completely suppressed.The reaction proceeds under mild conditions and is favorable to the esterification and amidation of thermally-,chemically- and ultraviolet-sensitive 13-cis-retinoic acid and its analogues.
To improve the synthetic method of 13-cis-retinoic acid derivatives,the title compounds were synthesized directly from 13-cis-retinoic acid and alcohols,phenols or amines with DCC as the condensation reagent under the catalysis of 4-(dimethylamino) pyridinium p-toluenesulfonate prepared in our lab.Eight new compounds were obtained in 80%~95% yields and in a high isomeric purity,which were characterized by NMR.The side reaction that converts 13-cis-retinoic acid to unreactive N-retinoylurea was completely suppressed.The reaction proceeds under mild conditions and is favorable to the esterification and amidation of thermally-,chemically- and ultraviolet-sensitive 13-cis-retinoic acid and its analogues.
2007, 24(5): 525-529
Abstract:
Carbon supported Pd(Pd/C) catalyst for the oxidation of formic acid in the direct formic acid fuel cell (DFAFC) was prepared with an improved organic sol method.When the Pd/C catalyst is prepared via the improved organic sol method with ethanol as the solvent and SnCl2 as the reductant,the procedure is simple and the cost is low.Especially,it was found that in this method,controlling the evaporation temperature of the solvent could control the average size and the relative crystallinity of the Pd particles in the Pd/C catalyst.The evaporation temperature of the solvent is not proportional to the average size and the relative crystallinity of the Pd particles in the Pd/C catalyst.When a suitable evaporation temperature is selected,the Pd/C catalyst with the average size as small as 6.5 nm and the relative crystallinity as low as 2.85 of the Pd particles could be obtained.It was found that the Pd/C catalyst with smaller average size and lower relative crystallinity shows a high electrocatalytic performance for the oxidation of formic acid.
Carbon supported Pd(Pd/C) catalyst for the oxidation of formic acid in the direct formic acid fuel cell (DFAFC) was prepared with an improved organic sol method.When the Pd/C catalyst is prepared via the improved organic sol method with ethanol as the solvent and SnCl2 as the reductant,the procedure is simple and the cost is low.Especially,it was found that in this method,controlling the evaporation temperature of the solvent could control the average size and the relative crystallinity of the Pd particles in the Pd/C catalyst.The evaporation temperature of the solvent is not proportional to the average size and the relative crystallinity of the Pd particles in the Pd/C catalyst.When a suitable evaporation temperature is selected,the Pd/C catalyst with the average size as small as 6.5 nm and the relative crystallinity as low as 2.85 of the Pd particles could be obtained.It was found that the Pd/C catalyst with smaller average size and lower relative crystallinity shows a high electrocatalytic performance for the oxidation of formic acid.
2007, 24(5): 530-533
Abstract:
The haptene of dibutyl phthalate (DBP) was conjugated to bovine serum by azo coupling.The conjugate was used as an immunogen.High titer polyclonal antibodies against dibutyl phthalate were produced from New Zealand white rabbits immunized with the immunogen.The final sera had titers against DBP with dilutions of 1:32~1:64 with double immunodiffusion,and 1:6 400~1:12 800 with indirect competitive fluorescence immunoassay.After an acceptable antibody titer was observed,the animals were exsanguinated and antiserum was purified.The purified IgG fractions were lyophilized aliquoted into vials,and stored at -20℃.An indirect fluorescence immunoassay to detect antibody was developed.The analysis experiment of anti-DBP by indirect competitive fluorescence immunoassay showed that anti-DBP antibody was crossreacted with other similar phthalate compounds,such as dimethyl phthalate (DMP),diethyl phthalate (DEP),dipropyl phthalate (DPrP),dicyclohexyl phthalate (DCHP),di-n-pentyl phthalate (DPP) and diethylhexyl phthalate (DEHP),and the cross reactivities were less than 10%.Therefore,this anti-DBP antibody could be interesting for developing the fluorescence immunoassay of DBP.
The haptene of dibutyl phthalate (DBP) was conjugated to bovine serum by azo coupling.The conjugate was used as an immunogen.High titer polyclonal antibodies against dibutyl phthalate were produced from New Zealand white rabbits immunized with the immunogen.The final sera had titers against DBP with dilutions of 1:32~1:64 with double immunodiffusion,and 1:6 400~1:12 800 with indirect competitive fluorescence immunoassay.After an acceptable antibody titer was observed,the animals were exsanguinated and antiserum was purified.The purified IgG fractions were lyophilized aliquoted into vials,and stored at -20℃.An indirect fluorescence immunoassay to detect antibody was developed.The analysis experiment of anti-DBP by indirect competitive fluorescence immunoassay showed that anti-DBP antibody was crossreacted with other similar phthalate compounds,such as dimethyl phthalate (DMP),diethyl phthalate (DEP),dipropyl phthalate (DPrP),dicyclohexyl phthalate (DCHP),di-n-pentyl phthalate (DPP) and diethylhexyl phthalate (DEHP),and the cross reactivities were less than 10%.Therefore,this anti-DBP antibody could be interesting for developing the fluorescence immunoassay of DBP.
2007, 24(5): 534-539
Abstract:
The plasma degradation of crystal violet by glow discharge electrolysis is presented.The factors for the degradation and/or decoloration processes were studied.The decoloration efficiency of crystal violet could be increased considerably by increasing electrolyte concentration and voltage applied.After considering the service life of the Pt electrode used,an electrolyte concentration of 2 g/L Na2SO4 and an applied voltage of 600 V were chosen as the optimum experimental conditions.Increasing the initial pH of the solution could accelerate the decoloration of crystal violet.Addition of H2O2 can increase the rate of decoloration,too.Furthermore,the presence of 0.4 mmol/L Fe2+ can improve the decoloration rate of crystal violet from 13.64% to 91.36% within 5 minutes.The addition of a radical scavenger n-butanol decreases the decoloration efficiency of crystal violet,which shows that hydroxyl radicals play an important role in the degradation process.Based on ultraviolet (UV) absorption spectra obtained during the degradation process,more than 93% crystal violet was decolorized,and 74% crystal violet was degraded after oxidation for 40 minutes.The possible degradation pathway for crystal violet is proposed.The results show that the combination of glow discharge plasma,H2O2 and/or Fe2+ can accelerate the degradation of crystal violet considerably.
The plasma degradation of crystal violet by glow discharge electrolysis is presented.The factors for the degradation and/or decoloration processes were studied.The decoloration efficiency of crystal violet could be increased considerably by increasing electrolyte concentration and voltage applied.After considering the service life of the Pt electrode used,an electrolyte concentration of 2 g/L Na2SO4 and an applied voltage of 600 V were chosen as the optimum experimental conditions.Increasing the initial pH of the solution could accelerate the decoloration of crystal violet.Addition of H2O2 can increase the rate of decoloration,too.Furthermore,the presence of 0.4 mmol/L Fe2+ can improve the decoloration rate of crystal violet from 13.64% to 91.36% within 5 minutes.The addition of a radical scavenger n-butanol decreases the decoloration efficiency of crystal violet,which shows that hydroxyl radicals play an important role in the degradation process.Based on ultraviolet (UV) absorption spectra obtained during the degradation process,more than 93% crystal violet was decolorized,and 74% crystal violet was degraded after oxidation for 40 minutes.The possible degradation pathway for crystal violet is proposed.The results show that the combination of glow discharge plasma,H2O2 and/or Fe2+ can accelerate the degradation of crystal violet considerably.
2007, 24(5): 540-545
Abstract:
A multi-wall carbon nanotubes (MWNTs)-Nafion film-coated glassy carbon electrode (GCE) was fabricated,and the electrochemical behavior of ofloxacin on the MWNTs-Nafion film-coated GCE was investigated via cyclic voltammetry (CV),linearsweep voltammetry (LSV),and electrochemical impedance spectroscopy (EIS).The oxidation peak current of ofloxacin increased significantly at the MWNTs-Nafion film modified GCE,compared with that at a bare GCE.This nano-structured film electrode exhibited excellent enhancement effects on the electrochemical oxidation of ofloxacin.A well-defined oxidation peak attributed to ofloxacin was observed at 0.97 V and was applied to the determination of ofloxacin.The oxidation peak current was proportional to ofloxacin concentration in the ranges of 1.0×10-8~1.0×10-6 mol/L and 1.0×10-6~2.0×10-5 mol/L,and a detection limit of 8.0×10-9 mol/L was obtained for 400 s accumulation at open circuit (S/N=3).The method was demonstrated via determining ofloxacin in human urine and the result was satisfactory.
A multi-wall carbon nanotubes (MWNTs)-Nafion film-coated glassy carbon electrode (GCE) was fabricated,and the electrochemical behavior of ofloxacin on the MWNTs-Nafion film-coated GCE was investigated via cyclic voltammetry (CV),linearsweep voltammetry (LSV),and electrochemical impedance spectroscopy (EIS).The oxidation peak current of ofloxacin increased significantly at the MWNTs-Nafion film modified GCE,compared with that at a bare GCE.This nano-structured film electrode exhibited excellent enhancement effects on the electrochemical oxidation of ofloxacin.A well-defined oxidation peak attributed to ofloxacin was observed at 0.97 V and was applied to the determination of ofloxacin.The oxidation peak current was proportional to ofloxacin concentration in the ranges of 1.0×10-8~1.0×10-6 mol/L and 1.0×10-6~2.0×10-5 mol/L,and a detection limit of 8.0×10-9 mol/L was obtained for 400 s accumulation at open circuit (S/N=3).The method was demonstrated via determining ofloxacin in human urine and the result was satisfactory.
2007, 24(5): 546-550
Abstract:
Core/shell composite microparticles with silica nanoparticle as core and crosslinked poly (tert-butylmethacrylate) as shell were prepared by seed-emulsion polymerization utilizing 3-(trimethoxysilyl) propyl methacrylate (MPS) modified silica particles as seeds,tert-butylmethacrylate as monomer and sodium dodecyl sulfate (SDS) as emulsifier.The microparticles were transformed into pH-sensitive inorganic/organic composite microparticles by hydrolysis.The factors affecting the morphological structure of the composite microparticles were investigated,and it was found that the formation of pure poly (tert-butylmethacrylate) latex particles in the polymerization process could be avoided by controlling the solid content of the silica seed emulsion in the range from 1.5% to 2%.Pure poly (tert-butylmethacrylate) latex particles tended to be formed when the content of SDS exceeded 0.3%,while the core/shell composite microparticles were readily flocculated if the content of SDS was below 0.15%.Their shell thickness was enhanced as the amount of the monomer and crosslinker was increased,but their excessive use led to the formation of pure poly (tert-butylmethacrylate) latex particles and the flocculation of the formed core/shell composite microparticles.The core/shell morphological structure and chemical composition of the composite microparticles were confirmed by TEM,NMR,FTIR and contact angle analysis results.
Core/shell composite microparticles with silica nanoparticle as core and crosslinked poly (tert-butylmethacrylate) as shell were prepared by seed-emulsion polymerization utilizing 3-(trimethoxysilyl) propyl methacrylate (MPS) modified silica particles as seeds,tert-butylmethacrylate as monomer and sodium dodecyl sulfate (SDS) as emulsifier.The microparticles were transformed into pH-sensitive inorganic/organic composite microparticles by hydrolysis.The factors affecting the morphological structure of the composite microparticles were investigated,and it was found that the formation of pure poly (tert-butylmethacrylate) latex particles in the polymerization process could be avoided by controlling the solid content of the silica seed emulsion in the range from 1.5% to 2%.Pure poly (tert-butylmethacrylate) latex particles tended to be formed when the content of SDS exceeded 0.3%,while the core/shell composite microparticles were readily flocculated if the content of SDS was below 0.15%.Their shell thickness was enhanced as the amount of the monomer and crosslinker was increased,but their excessive use led to the formation of pure poly (tert-butylmethacrylate) latex particles and the flocculation of the formed core/shell composite microparticles.The core/shell morphological structure and chemical composition of the composite microparticles were confirmed by TEM,NMR,FTIR and contact angle analysis results.
2007, 24(5): 551-555
Abstract:
In NH3-NH4Cl buffer solutions,the reactions of ammonium pyrrolidinedithiocarbamate with some metal ions such as Cu(Ⅱ),Ag(Ⅰ),Pd(Ⅱ),Ni(Ⅱ) and Co(Ⅱ) form chelate complex particles and yield a liquid-solid surface,which show different colors and resonance light scattering (RLS) effects.The five chelate particle systems,Cu(Ⅱ)-APDC,Ag(Ⅰ)-APDC,Pd(Ⅱ)-APDC,Ni(Ⅱ)-APDC and Co(Ⅱ)-APDC,exhibit resonance scattering peaks at 310 nm,360 nm,360 nm,360 nm and 400 nm,respectively.Under the chosen conditions,there is a good linear relationship between the metal ion concentrations and the RLS intensity.When APDC in (Cu-APDC) was oxidized by ClO2,the RLS intensity of this system was reduced linearly with its concentration.Based on this fact,a new resonance scattering spectral method is proposed for the determination of 7.56×10-9~756×10-9 g/mL ClO2,with a detection limit of 3.0×10-9 g/mL ClO2.Its regress equation is ΔI=87.9 cCl+0.55,with a relative coefficient of 0.997 8.It was applied to the analysis of ClO2 in water samples with a satisfactory result.
In NH3-NH4Cl buffer solutions,the reactions of ammonium pyrrolidinedithiocarbamate with some metal ions such as Cu(Ⅱ),Ag(Ⅰ),Pd(Ⅱ),Ni(Ⅱ) and Co(Ⅱ) form chelate complex particles and yield a liquid-solid surface,which show different colors and resonance light scattering (RLS) effects.The five chelate particle systems,Cu(Ⅱ)-APDC,Ag(Ⅰ)-APDC,Pd(Ⅱ)-APDC,Ni(Ⅱ)-APDC and Co(Ⅱ)-APDC,exhibit resonance scattering peaks at 310 nm,360 nm,360 nm,360 nm and 400 nm,respectively.Under the chosen conditions,there is a good linear relationship between the metal ion concentrations and the RLS intensity.When APDC in (Cu-APDC) was oxidized by ClO2,the RLS intensity of this system was reduced linearly with its concentration.Based on this fact,a new resonance scattering spectral method is proposed for the determination of 7.56×10-9~756×10-9 g/mL ClO2,with a detection limit of 3.0×10-9 g/mL ClO2.Its regress equation is ΔI=87.9 cCl+0.55,with a relative coefficient of 0.997 8.It was applied to the analysis of ClO2 in water samples with a satisfactory result.
2007, 24(5): 556-560
Abstract:
A stable and uniform MgO layer was coated on the surface of LiCoO2 cathode material by solution method with Mg-PAA.A layer of LiCo1-xMgxO2 solid solution was formed at the interface between LiCoO2 and the MgO layer.The structure and performance of the MgO coated and uncoated LiCoO2 were characterized by means of XRD,SEM,AES.The results show that a solid electrolyte layer was formed on the surface of LiCoO2,which can reduce the direct contact between LiCoO2 and electrolyte,and thus effectively suppress the interaction between them.The structure stability,lattice distortion and cycle-reversibility at a high voltage for LiCoO2 can be improved obviously by the surface coating.There was only 5% or 6% capacity fading after 100 cycles for the battery with coated-LiCoO2 cathode.
A stable and uniform MgO layer was coated on the surface of LiCoO2 cathode material by solution method with Mg-PAA.A layer of LiCo1-xMgxO2 solid solution was formed at the interface between LiCoO2 and the MgO layer.The structure and performance of the MgO coated and uncoated LiCoO2 were characterized by means of XRD,SEM,AES.The results show that a solid electrolyte layer was formed on the surface of LiCoO2,which can reduce the direct contact between LiCoO2 and electrolyte,and thus effectively suppress the interaction between them.The structure stability,lattice distortion and cycle-reversibility at a high voltage for LiCoO2 can be improved obviously by the surface coating.There was only 5% or 6% capacity fading after 100 cycles for the battery with coated-LiCoO2 cathode.
2007, 24(5): 561-564
Abstract:
A Series of MoO3/K2O/SiO2 catalysts with different K/Mo molar ratios were prepared and characte-rized using XRD and TPR.XRD characterization shows that with the increase of potassium content,polymolybdate species depolymerizes progressively,leading to the formation of K2MoO4 species.TPR characterization shows that there are two kinds of Mo coordination species,namely octahedral molybdenum (Mo(Oh)) and tetrahedron molybdenum (Mo(Td)).The reduction peak of Mo(Oh) was found to appear at about 770 K,and that of Mo(Td) at about 1 000 K.The addition of a small amounts of potassium can decrease the interaction between Mo and SiO2 and lower the reduction temperature of Mo(Oh) by about 70 K.With the increase of potassium content,the amount of Mo(Td) increased,while that of Mo(Oh) decreased,leading to the more difficult reduction of Mo.The performance of the catalysts for methyl mercaptan synthesis from high H2S-containing syngas showed that with the increase of Mo(Oh),the activity of the catalyst increased.
A Series of MoO3/K2O/SiO2 catalysts with different K/Mo molar ratios were prepared and characte-rized using XRD and TPR.XRD characterization shows that with the increase of potassium content,polymolybdate species depolymerizes progressively,leading to the formation of K2MoO4 species.TPR characterization shows that there are two kinds of Mo coordination species,namely octahedral molybdenum (Mo(Oh)) and tetrahedron molybdenum (Mo(Td)).The reduction peak of Mo(Oh) was found to appear at about 770 K,and that of Mo(Td) at about 1 000 K.The addition of a small amounts of potassium can decrease the interaction between Mo and SiO2 and lower the reduction temperature of Mo(Oh) by about 70 K.With the increase of potassium content,the amount of Mo(Td) increased,while that of Mo(Oh) decreased,leading to the more difficult reduction of Mo.The performance of the catalysts for methyl mercaptan synthesis from high H2S-containing syngas showed that with the increase of Mo(Oh),the activity of the catalyst increased.
2007, 24(5): 565-569
Abstract:
Li2CO3 was added while a series of CaSiO3:Pb2+,Mn2+ phosphor were synthesized by Sol-Gel method,and the influence of Li+ doped on the crystal structure and luminescent properties of CaSiO3:Pb2+,Mn2+ were investigated via PL,DTA-TG,XRD and SEM.The results show that when the sample was calcinated at 900℃ and the mass fraction of Li+ was no more than 0.25%,no shift in the emission band was found.When the mass fraction of Li+ was 0.15%,the emission intensity of the sample was most prominent,and the β-CaSiO3 crystalline phase was observed.When the mass fraction of Li+ was more than 0.25%,blue shift in the emission band was observed.When the mass fraction of Li+ was 0.65%,the emission intensity of the sample was enhanced 3.5 times compared to that of the sample without Li+doped,and the emission band shifted from 650 nm to around 615 nm,and a new sort of material,Li2Ca3Si6O16 was observed.It was also found that the synthesis temperature was decreased as Li+ was added.The best calcination temperature for the sample without Li+ doped was 1 200℃;when the mass fractions of Li+ were 0.15% and 0.65%,the best calcination temperatures were 1 100℃ and 900℃ respectively.SEM also showed that with Li+ added,the shape of the products gradually turned irregular from 3-dimensional network structure,and the size of the phosphor particles became smaller.
Li2CO3 was added while a series of CaSiO3:Pb2+,Mn2+ phosphor were synthesized by Sol-Gel method,and the influence of Li+ doped on the crystal structure and luminescent properties of CaSiO3:Pb2+,Mn2+ were investigated via PL,DTA-TG,XRD and SEM.The results show that when the sample was calcinated at 900℃ and the mass fraction of Li+ was no more than 0.25%,no shift in the emission band was found.When the mass fraction of Li+ was 0.15%,the emission intensity of the sample was most prominent,and the β-CaSiO3 crystalline phase was observed.When the mass fraction of Li+ was more than 0.25%,blue shift in the emission band was observed.When the mass fraction of Li+ was 0.65%,the emission intensity of the sample was enhanced 3.5 times compared to that of the sample without Li+doped,and the emission band shifted from 650 nm to around 615 nm,and a new sort of material,Li2Ca3Si6O16 was observed.It was also found that the synthesis temperature was decreased as Li+ was added.The best calcination temperature for the sample without Li+ doped was 1 200℃;when the mass fractions of Li+ were 0.15% and 0.65%,the best calcination temperatures were 1 100℃ and 900℃ respectively.SEM also showed that with Li+ added,the shape of the products gradually turned irregular from 3-dimensional network structure,and the size of the phosphor particles became smaller.
2007, 24(5): 570-574
Abstract:
The combination of ultrasound (US) and ultraviolet irradiation (UV) with TiO2 nanoparticles as the photocatalyst was used to degrade poly (vinyl alcohol)(PVA) in aqueous solution.US/UV/TiO2 technique was considerably more effective than US or UV alone,and ultrasound and ultraviolet light exhibited synergistic effect.The sonophotocatalytic activity of rutile TiO2 particles was obviously higher than that of anatase TiO2 particles.The degradation rate of PVA is inversely proportional to the initial PVA concentration.The results show that it is more effective for PVA to be degraded under acidic or basic condition.The order of the reaction rates at different pH was pH 8.5 >pH 4.5 >pH 5.5 >pH 7.0.The sonophotocatalytic degradation of PVA in the presence of nano anatase TiO2 catalyst followed a pseudo first-order kinetics.The reaction rate constant was 0.037 min-1.The degradation ratio of PVA reached almost 100.0% within 80 min under the experimental conditions of 40 kHz ultrasonic frequency,1.0 g/L rutile TiO2 catalyst,pH=5.5,and 30℃ temperature at an initial PVA concentration of 90 mg/L.GC,DTG and XPS results showed that the intermediates containing C-O,O-C=O groups were formed during the degradation reaction.The PVA finally mineralized to CO2 and H2O.
The combination of ultrasound (US) and ultraviolet irradiation (UV) with TiO2 nanoparticles as the photocatalyst was used to degrade poly (vinyl alcohol)(PVA) in aqueous solution.US/UV/TiO2 technique was considerably more effective than US or UV alone,and ultrasound and ultraviolet light exhibited synergistic effect.The sonophotocatalytic activity of rutile TiO2 particles was obviously higher than that of anatase TiO2 particles.The degradation rate of PVA is inversely proportional to the initial PVA concentration.The results show that it is more effective for PVA to be degraded under acidic or basic condition.The order of the reaction rates at different pH was pH 8.5 >pH 4.5 >pH 5.5 >pH 7.0.The sonophotocatalytic degradation of PVA in the presence of nano anatase TiO2 catalyst followed a pseudo first-order kinetics.The reaction rate constant was 0.037 min-1.The degradation ratio of PVA reached almost 100.0% within 80 min under the experimental conditions of 40 kHz ultrasonic frequency,1.0 g/L rutile TiO2 catalyst,pH=5.5,and 30℃ temperature at an initial PVA concentration of 90 mg/L.GC,DTG and XPS results showed that the intermediates containing C-O,O-C=O groups were formed during the degradation reaction.The PVA finally mineralized to CO2 and H2O.
2007, 24(5): 575-579
Abstract:
The adsorption selectivity of fluoxetine enantiomers on phenylcarbamolyted β-cyclodextrin was investigated by HPLC on a Cyclobond Ⅰ 2000 DM column.The isothermal adsorption curves were measured at three temperatures.It was found that in a methanol-buffer solution system the adsorptive capacity of Sfluoxetine on phenylcarbamolyted β-cyclodextrin is always greater than that of R-fluoxetine,and the isothermal adsorption of both enantiomers matches the Langumir isotherm adsorption equation and is advantageous adsorption.It was also found that in an acetonitrile-buffer solution system the adsorptive capacity of S-fluoxetine on phenylcarbamolyted β-cyclodextrin is also greater than that of R-fluoxetine,but it matches the Freundlich isotherm equation.Experimental results show that fluoxetine enantiomers can be resolved probably by HPLC on a phenylcarbamolyted β-cyclodextrin column.
The adsorption selectivity of fluoxetine enantiomers on phenylcarbamolyted β-cyclodextrin was investigated by HPLC on a Cyclobond Ⅰ 2000 DM column.The isothermal adsorption curves were measured at three temperatures.It was found that in a methanol-buffer solution system the adsorptive capacity of Sfluoxetine on phenylcarbamolyted β-cyclodextrin is always greater than that of R-fluoxetine,and the isothermal adsorption of both enantiomers matches the Langumir isotherm adsorption equation and is advantageous adsorption.It was also found that in an acetonitrile-buffer solution system the adsorptive capacity of S-fluoxetine on phenylcarbamolyted β-cyclodextrin is also greater than that of R-fluoxetine,but it matches the Freundlich isotherm equation.Experimental results show that fluoxetine enantiomers can be resolved probably by HPLC on a phenylcarbamolyted β-cyclodextrin column.
2007, 24(5): 580-584
Abstract:
Polyethylenimine (PEI) was grafted on silica gel particle surface with γ-chloropropyltrimethoxysilane as the coupling agent,and novel composite adsorption material PEI/SiO2 for biomedical application was prepared.The effect of pH,ionic strength of the medium and the bound amount of PEI on PEI/SiO2 on the adsorption quantity of PEI/SiO2 for bilirubin was examined.The static adsorption experiment results show that PEI/SiO2 has a strong adsorption ability for Bilirubin.The PEI macromolecules on silica particles can produce a strong adsorption effect for bilirubin by means of electrostatic interaction.The isothermal adsorption obeyed the Freundlich equation,and the equilibrium adsorption amount reached 13.17 mg/g as the preliminary concentration of bilirubin was 0.590 g/L.The pH value of the aqueous solution has a great effect on the adsorption property of PEI/SiO2.In a near neutral solution (pH=6),there was a maximum adsorption amount,and in acidic and basic solutions,the adsorption actions were all weak.
Polyethylenimine (PEI) was grafted on silica gel particle surface with γ-chloropropyltrimethoxysilane as the coupling agent,and novel composite adsorption material PEI/SiO2 for biomedical application was prepared.The effect of pH,ionic strength of the medium and the bound amount of PEI on PEI/SiO2 on the adsorption quantity of PEI/SiO2 for bilirubin was examined.The static adsorption experiment results show that PEI/SiO2 has a strong adsorption ability for Bilirubin.The PEI macromolecules on silica particles can produce a strong adsorption effect for bilirubin by means of electrostatic interaction.The isothermal adsorption obeyed the Freundlich equation,and the equilibrium adsorption amount reached 13.17 mg/g as the preliminary concentration of bilirubin was 0.590 g/L.The pH value of the aqueous solution has a great effect on the adsorption property of PEI/SiO2.In a near neutral solution (pH=6),there was a maximum adsorption amount,and in acidic and basic solutions,the adsorption actions were all weak.
2007, 24(5): 585-588
Abstract:
A novel extracting agent for solid phase extraction was prepared by immobilizing dye ligand onto the surface of nonporous Urea-Formaldehyde resin-Zirconia composite microspheres via nucleophilic reaction,where the amido groups on the surface of the microspheres reacted with the active chloride in the dye.Bovine serum albumin (BSA) was chosen as the testing sample,and the kinetics and thermodynamics of BSA adsorption on the newly synthesized extracting agent were investigated under different conditions.The result indicates that the extraction capacity of the extracting agent reached 34.5 mg/g,and the extraction can be described by Langmuir adsorption isotherm.The extraction amount reached a maximum at pH=4.6,and when the experiment was carried out for 2 hours,the extraction amount reached 80% of the maximum.The extracted protein was easily eluted by 1 mol/L KSCN,and the elution efficiency was 93.5%,and also the elution was reproducible.This extracting agent could be used to separate interferential proteins and enrich target protein before HPLC analysis.
A novel extracting agent for solid phase extraction was prepared by immobilizing dye ligand onto the surface of nonporous Urea-Formaldehyde resin-Zirconia composite microspheres via nucleophilic reaction,where the amido groups on the surface of the microspheres reacted with the active chloride in the dye.Bovine serum albumin (BSA) was chosen as the testing sample,and the kinetics and thermodynamics of BSA adsorption on the newly synthesized extracting agent were investigated under different conditions.The result indicates that the extraction capacity of the extracting agent reached 34.5 mg/g,and the extraction can be described by Langmuir adsorption isotherm.The extraction amount reached a maximum at pH=4.6,and when the experiment was carried out for 2 hours,the extraction amount reached 80% of the maximum.The extracted protein was easily eluted by 1 mol/L KSCN,and the elution efficiency was 93.5%,and also the elution was reproducible.This extracting agent could be used to separate interferential proteins and enrich target protein before HPLC analysis.
2007, 24(5): 589-592
Abstract:
UF-resin was used to encapsulate chlorpyrifos via in-situ polymerization.The factors affecting the morphology and the encapsulation efficiency of the microcapsules were investigated,and the drug loading was also determined.The results show that at a heating rate of 0.5℃/min,a stirring speed of 20 r/min and with 0.4% sodium chloride added in the solidifying period,microcapsules with good shape could be prepared.Different core/wall ratios did not significantly affect the encapsulation ratio,and the encapsulation ratios for 12,15,18,21 and 24 g UF-prepolymer solutions were 98.56%,98.89%,99.34%,98.25% and 98.21%,respectively.However,acidification and solidifying time could affect encapsulation ratio evidently,and the optimum periods of acidification and solidifying were 60 min and 100 min respectively.The drug loading ratio of the microcapsules was as high as 0.642 g/g.
UF-resin was used to encapsulate chlorpyrifos via in-situ polymerization.The factors affecting the morphology and the encapsulation efficiency of the microcapsules were investigated,and the drug loading was also determined.The results show that at a heating rate of 0.5℃/min,a stirring speed of 20 r/min and with 0.4% sodium chloride added in the solidifying period,microcapsules with good shape could be prepared.Different core/wall ratios did not significantly affect the encapsulation ratio,and the encapsulation ratios for 12,15,18,21 and 24 g UF-prepolymer solutions were 98.56%,98.89%,99.34%,98.25% and 98.21%,respectively.However,acidification and solidifying time could affect encapsulation ratio evidently,and the optimum periods of acidification and solidifying were 60 min and 100 min respectively.The drug loading ratio of the microcapsules was as high as 0.642 g/g.
2007, 24(5): 593-595
Abstract:
A novel chemiluminescence system for the determination of bismerthiazol is described in this paper.It is based on the chemiluminescence reaction of bismerthiazol and Ce(Ⅳ) in nitric acid solution.The emission intensity can be enhanced greatly by Rhodamine B.The chemiluminescence intensity was propor-tional to bismerthiazol concentration over a range of 30~1 000 μg/L.The detection limit was 12 μg/L(3σ) and the relative standard deviation was 2.4% for 500 μg/L bismerthiazol (n=11).The proposed method was successfully applied to the determination of bismerthiazol in water and in rice.The recovery was 96.4%~104.1%.
A novel chemiluminescence system for the determination of bismerthiazol is described in this paper.It is based on the chemiluminescence reaction of bismerthiazol and Ce(Ⅳ) in nitric acid solution.The emission intensity can be enhanced greatly by Rhodamine B.The chemiluminescence intensity was propor-tional to bismerthiazol concentration over a range of 30~1 000 μg/L.The detection limit was 12 μg/L(3σ) and the relative standard deviation was 2.4% for 500 μg/L bismerthiazol (n=11).The proposed method was successfully applied to the determination of bismerthiazol in water and in rice.The recovery was 96.4%~104.1%.
Synthesis and Herbicidal Activity of α-[2-(Fluorosubstituted phenoxy) propionyloxy]alkylphosphonates
2007, 24(5): 596-598
Abstract:
In order to find new phosphonates with better herbicidal activity,fluorous group was introduced to α-oxophosphonates.Eight novel phosphonate derivatives were synthesized by the condensation reaction of 2-(fluoro-substituted phenoxy) propionyl chloride with α-hydroxyphosphonates in chloroform under reflux in yields of 20%~71%.The molecular structures of all the compounds were confirmed by IR,1H NMR and MS.Preliminary bioassay results show that some of these compounds have better inhibiting effect against the roots of monocotyledon and dicotyledon.Inhibitory rates of compounds Ⅲe~Ⅲh against the roots of rape and barnyard grass were more than 93%.
In order to find new phosphonates with better herbicidal activity,fluorous group was introduced to α-oxophosphonates.Eight novel phosphonate derivatives were synthesized by the condensation reaction of 2-(fluoro-substituted phenoxy) propionyl chloride with α-hydroxyphosphonates in chloroform under reflux in yields of 20%~71%.The molecular structures of all the compounds were confirmed by IR,1H NMR and MS.Preliminary bioassay results show that some of these compounds have better inhibiting effect against the roots of monocotyledon and dicotyledon.Inhibitory rates of compounds Ⅲe~Ⅲh against the roots of rape and barnyard grass were more than 93%.
2007, 24(5): 599-601
Abstract:
The power-time curves of the micelle formation process were determined with microcalorimetry for sodium laurate sdution in N,N-dimehyl acetamide containing cosurfactant (heptanol,octanol,nonanol and decanol).The critical micelle concentration (CMC) and ΔHmθ were measured,and ΔGmθ and ΔSmθ were calculated.The relationship between the carbon number of the alcohol,the alcohol concentration and the thermodynamic properties (CMC,ΔHmθ,ΔGmθ and ΔSmθ) were discussed.For the N,N-dimethyl acetamide solution of sodium laurate,the CMC decreased with the increase of the carbon number of the alcohol,and increased with the increase of the alcohol concentration.The micelle formation process is an exothermic process,and -ΔHmθ increased with the increase of the carbon number of the alcohol,and the alcohol concentration.
The power-time curves of the micelle formation process were determined with microcalorimetry for sodium laurate sdution in N,N-dimehyl acetamide containing cosurfactant (heptanol,octanol,nonanol and decanol).The critical micelle concentration (CMC) and ΔHmθ were measured,and ΔGmθ and ΔSmθ were calculated.The relationship between the carbon number of the alcohol,the alcohol concentration and the thermodynamic properties (CMC,ΔHmθ,ΔGmθ and ΔSmθ) were discussed.For the N,N-dimethyl acetamide solution of sodium laurate,the CMC decreased with the increase of the carbon number of the alcohol,and increased with the increase of the alcohol concentration.The micelle formation process is an exothermic process,and -ΔHmθ increased with the increase of the carbon number of the alcohol,and the alcohol concentration.
2007, 24(5): 602-604
Abstract:
Ion chromatography was applied to determine the concentration of LiPF6 in the electrolyte solution for lithium-ion batteries.The optimal pretreatment parameters were confirmed through a series of experiments:chloronitric acid (1:3) was found to be the most effective decomposer for the electrolyte solution,when its volume was equal to that of the electrolyte solution.The preferred reaction time was not less than 12 hours.The recovery rates of F- and PO43- were both higher than 100%,and the relative error for the concentration of LiPF6 calculated from PO43- was 1.2%,showing a high quantitative accuracy.
Ion chromatography was applied to determine the concentration of LiPF6 in the electrolyte solution for lithium-ion batteries.The optimal pretreatment parameters were confirmed through a series of experiments:chloronitric acid (1:3) was found to be the most effective decomposer for the electrolyte solution,when its volume was equal to that of the electrolyte solution.The preferred reaction time was not less than 12 hours.The recovery rates of F- and PO43- were both higher than 100%,and the relative error for the concentration of LiPF6 calculated from PO43- was 1.2%,showing a high quantitative accuracy.
