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2001 Volume 18 Issue 7
2001, 18(7): 509-512
Abstract:
The corrosion resistance of the electroless composite coatings consisted of nanometer zinc salt and nickel-phosphorus on the surface of silicon-steel have been investigated as function of nanoparticle concentrations.The corrosion resistance tests include accelerated corrosion, high temperature oxidation and adhesiveness resistance tests.The coating thickness and morphology were detected by weighting and SEM observation.The results showed that when nanometer particle concentration was of 0.5 g/L, the surface of the coating was homogeneous and polishing with corrosion resistance superior to silicon-steel specimen and even to nickel-phosphorus coating.
The corrosion resistance of the electroless composite coatings consisted of nanometer zinc salt and nickel-phosphorus on the surface of silicon-steel have been investigated as function of nanoparticle concentrations.The corrosion resistance tests include accelerated corrosion, high temperature oxidation and adhesiveness resistance tests.The coating thickness and morphology were detected by weighting and SEM observation.The results showed that when nanometer particle concentration was of 0.5 g/L, the surface of the coating was homogeneous and polishing with corrosion resistance superior to silicon-steel specimen and even to nickel-phosphorus coating.
2001, 18(7): 513-516
Abstract:
The title compounds were synthesized from substituted pyrazolyl aldehyde as starting material, which were treated with hydrazine hydrate to give hydrazone(M-1).M-1 were reacted with isocyanates,isothiocyanates to yield 1~19.The structures of compounds were confirmed by elemental analyses, 1H NMR、IR and MS.The preliminary bioassay indicated that some of them displayed fungicidal activities.
The title compounds were synthesized from substituted pyrazolyl aldehyde as starting material, which were treated with hydrazine hydrate to give hydrazone(M-1).M-1 were reacted with isocyanates,isothiocyanates to yield 1~19.The structures of compounds were confirmed by elemental analyses, 1H NMR、IR and MS.The preliminary bioassay indicated that some of them displayed fungicidal activities.
2001, 18(7): 517-520
Abstract:
It was found for the first time that the Pt-TiOx/Ti and Pt-Ru-TiOx/Ti electrodes prepared by an electrochemical reduction-oxidation method show the excellent electrocatalytic activity and stability for the oxidation of methanol.The performance of the Pt-Ru-TiOx/Ti electrode is better than that of the Pt-TiOx/Ti electrode.Their high electrocatalytic activities for methonal oxidation is due to the high dispersion of Pt and Ru particles.The good stabilities can be attributed to the synergistic effect among Pt、Ru and TiOx which leads to the weak adsorption of CO at the electrodes, avoiding the electrodes being poisoned.
It was found for the first time that the Pt-TiOx/Ti and Pt-Ru-TiOx/Ti electrodes prepared by an electrochemical reduction-oxidation method show the excellent electrocatalytic activity and stability for the oxidation of methanol.The performance of the Pt-Ru-TiOx/Ti electrode is better than that of the Pt-TiOx/Ti electrode.Their high electrocatalytic activities for methonal oxidation is due to the high dispersion of Pt and Ru particles.The good stabilities can be attributed to the synergistic effect among Pt、Ru and TiOx which leads to the weak adsorption of CO at the electrodes, avoiding the electrodes being poisoned.
2001, 18(7): 521-523
Abstract:
The sulfonated poly(ethylene oxide)sulphate/polyurethane mixture was prepared from polyethylene oxide, 1,4-butanediol and methylene-bis(4-phenyl isocyanate).The samples were characterized by FT-IR and elemental analysis.The ionic conductivity was calculated based on the impedance measurements.The relation of the conductivity with ion concentration, sulfonated polyether content and temperature were discussed.The conductivity of 2.5×10-6 S/cm for the polymer electrolyte was obtained at room temperature.
The sulfonated poly(ethylene oxide)sulphate/polyurethane mixture was prepared from polyethylene oxide, 1,4-butanediol and methylene-bis(4-phenyl isocyanate).The samples were characterized by FT-IR and elemental analysis.The ionic conductivity was calculated based on the impedance measurements.The relation of the conductivity with ion concentration, sulfonated polyether content and temperature were discussed.The conductivity of 2.5×10-6 S/cm for the polymer electrolyte was obtained at room temperature.
2001, 18(7): 524-527
Abstract:
3-Heterocyclic aminomethylene-5,6-dihydro-6-alkyl(aryl)-2H-pyran-2,4-diones(3) were prepared by the condensation reaction of 6-alkyl(aryl)-5,6-dihydro-2H-pyran-2,4-diones with ethyl orthoformate and heterocyclic amines.A pair of conformational isomers was existed in products 3 due to the intramolecular hydrogen bonding.3 were tested in vitro against H.Oryzae, B.Cinerae and S.Sclerotiorum, showing some fungicidal activity.
3-Heterocyclic aminomethylene-5,6-dihydro-6-alkyl(aryl)-2H-pyran-2,4-diones(3) were prepared by the condensation reaction of 6-alkyl(aryl)-5,6-dihydro-2H-pyran-2,4-diones with ethyl orthoformate and heterocyclic amines.A pair of conformational isomers was existed in products 3 due to the intramolecular hydrogen bonding.3 were tested in vitro against H.Oryzae, B.Cinerae and S.Sclerotiorum, showing some fungicidal activity.
2001, 18(7): 528-531
Abstract:
The TiCl4/Ni(acac)2 complex catalysts were prepared.The effects of SiCl4 and polymerization conditions on the polymerization of ethylene and their apparent kinetics parameters have been studied.The products obtained were characterized by DSC, IR and 13C NMR.The results indicated that SiCl4 could increase the catalytic activity of the catalysts and the polymer obtained have low melting temperatures, crystallinity, density and some branches.The complex catalysts have the function of oligomerization and in situ copolymerization for ethylene.
The TiCl4/Ni(acac)2 complex catalysts were prepared.The effects of SiCl4 and polymerization conditions on the polymerization of ethylene and their apparent kinetics parameters have been studied.The products obtained were characterized by DSC, IR and 13C NMR.The results indicated that SiCl4 could increase the catalytic activity of the catalysts and the polymer obtained have low melting temperatures, crystallinity, density and some branches.The complex catalysts have the function of oligomerization and in situ copolymerization for ethylene.
2001, 18(7): 532-535
Abstract:
The extraction efficiencies of chlorophyll from fresh spinach were compared on soaking method and Arnon methods using various organic solvents.The results showed that the extraction efficiencies of chlorophyll with soaking methods using acetone or ethanol were higher by 21%~38% than that with Arnon method.The extraction efficiencies of chlorophyll with soaking methods by acetone or ethanol were higher than that by methanol or ether.Soaking method using a mixture of acetone and ethanol showed higher(by 39%) efficiency than using acetone or ethanol alone.The soaking method using mixture solution of acetone and ethanol shows synergistic character.The studies of synergistic extraction indicated that the mole ratio of ethanol in mixture solution was 0.5 and synergistic coefficiency R was 1.85 at the maximum of distribution ratio, and coordination number was 1 for acetone, ethanol, and mixture of acetone and ethanol coordinated chlorophyll.
The extraction efficiencies of chlorophyll from fresh spinach were compared on soaking method and Arnon methods using various organic solvents.The results showed that the extraction efficiencies of chlorophyll with soaking methods using acetone or ethanol were higher by 21%~38% than that with Arnon method.The extraction efficiencies of chlorophyll with soaking methods by acetone or ethanol were higher than that by methanol or ether.Soaking method using a mixture of acetone and ethanol showed higher(by 39%) efficiency than using acetone or ethanol alone.The soaking method using mixture solution of acetone and ethanol shows synergistic character.The studies of synergistic extraction indicated that the mole ratio of ethanol in mixture solution was 0.5 and synergistic coefficiency R was 1.85 at the maximum of distribution ratio, and coordination number was 1 for acetone, ethanol, and mixture of acetone and ethanol coordinated chlorophyll.
2001, 18(7): 536-539
Abstract:
Fe catalysts supported on inorganic oxides have been prepared by impregnation method.Their catalytic activities for the methanation of carbon dioxide are investigated.The results indicate that the oxide supports, in order of influence on the activity of Fe catalyst are titania > zirconia > sepiolite > alumina > silica.Both the conversion of carbon dioxide and the selectivity of methane strongly depend on the GHSV and the composition of feedstock.The ammonia treatment of Fe catalysts before calcination favors the methanation reaction.The introductions of other Ⅷ group or non-Ⅷ group metals influence the catalytic activities effectively.
Fe catalysts supported on inorganic oxides have been prepared by impregnation method.Their catalytic activities for the methanation of carbon dioxide are investigated.The results indicate that the oxide supports, in order of influence on the activity of Fe catalyst are titania > zirconia > sepiolite > alumina > silica.Both the conversion of carbon dioxide and the selectivity of methane strongly depend on the GHSV and the composition of feedstock.The ammonia treatment of Fe catalysts before calcination favors the methanation reaction.The introductions of other Ⅷ group or non-Ⅷ group metals influence the catalytic activities effectively.
2001, 18(7): 540-543
Abstract:
The effect of aluminium on the property of molybdenum nitride film electrode has been studied by cyclic voltammetry, XRD and SEM.The results show that the quantity of Al2(SO4)3·6H2O added strikingly influences the electrochemical behavior of the electrode prepared by dipping-calcination method.At optimum additive concentration in the dipping solution, the specific electric capacity of the electrode is 2.6 times that of the electrode prepared without additive in the dipping solution and the operating voltage value of the electrode increases by 0.13 V.The mechanism of aluminium affecting on the property of the film electrode is suggested that a lot of hole with size greater than 2 nm are formed in the film of the electrode, making the inner surface of the film wetted by the electrolyte solution and that there is an Al11O15N formed in the film of the electrode.
The effect of aluminium on the property of molybdenum nitride film electrode has been studied by cyclic voltammetry, XRD and SEM.The results show that the quantity of Al2(SO4)3·6H2O added strikingly influences the electrochemical behavior of the electrode prepared by dipping-calcination method.At optimum additive concentration in the dipping solution, the specific electric capacity of the electrode is 2.6 times that of the electrode prepared without additive in the dipping solution and the operating voltage value of the electrode increases by 0.13 V.The mechanism of aluminium affecting on the property of the film electrode is suggested that a lot of hole with size greater than 2 nm are formed in the film of the electrode, making the inner surface of the film wetted by the electrolyte solution and that there is an Al11O15N formed in the film of the electrode.
2001, 18(7): 544-547
Abstract:
The liquid crystal alignment with higher pretilt angles was obtained from polyimide(PI) having fluorinated main chains.The contact angles of the PI films were found to be dependent on the fluorine content of the PI.The morphology of the rubbed PI surfaces with fluorinated and unfluorinated main chains for liquid crystal alignment was compared by observation with atomic force microscope(AFM).The results showed that the surface of the rubbed PI films have regular and narrow intervals, aligned along the rubbing direction.The fluorinated PI surfaces are superior to the unfluorinated PI surfaces in regularity.
The liquid crystal alignment with higher pretilt angles was obtained from polyimide(PI) having fluorinated main chains.The contact angles of the PI films were found to be dependent on the fluorine content of the PI.The morphology of the rubbed PI surfaces with fluorinated and unfluorinated main chains for liquid crystal alignment was compared by observation with atomic force microscope(AFM).The results showed that the surface of the rubbed PI films have regular and narrow intervals, aligned along the rubbing direction.The fluorinated PI surfaces are superior to the unfluorinated PI surfaces in regularity.
2001, 18(7): 548-551
Abstract:
The effects of some hindered amine light stabilizers(HALS) and antioxidants on the radiation-induced coloration of polyethylene(PE) are studied by measuring the yellowness index(YI) of PE.It is found that all the HALS and antioxidants examined are effective in preventing PE from radiation-induced coloration.The YIs of PE with pentamethyl HALS(PMPM, PPMPM) are a little higher than YIs of PE added corresponding tetramethyl HALS(TMPM, PTMPM) when the irradiation dose is lower than 100 kGy, but when the irradiation dose is higher than 100 kGy, the YI of PE added pentamethyl HALS is low.Pentamethyl HALS is more effective in preventing PE from radiation-induced coloration when irradiation dose is high.The YI of PE added Irganox 1010 is the highest among those of PE added hindered phenol antioxidant Irganox 1076, Irganox 1010 or Irganox 1098 separately.The YI of PE added Irganox PS802 is lower than that of PE added Irgafos 168.Commonly, hindered phenol antioxidants are more effective than hydroperoxide decomposer antioxidants in preventing PE from radiation-induced coloration.The role of HALS and antioxidants played in preventing PE from radiation-induced coloration is discussed.
The effects of some hindered amine light stabilizers(HALS) and antioxidants on the radiation-induced coloration of polyethylene(PE) are studied by measuring the yellowness index(YI) of PE.It is found that all the HALS and antioxidants examined are effective in preventing PE from radiation-induced coloration.The YIs of PE with pentamethyl HALS(PMPM, PPMPM) are a little higher than YIs of PE added corresponding tetramethyl HALS(TMPM, PTMPM) when the irradiation dose is lower than 100 kGy, but when the irradiation dose is higher than 100 kGy, the YI of PE added pentamethyl HALS is low.Pentamethyl HALS is more effective in preventing PE from radiation-induced coloration when irradiation dose is high.The YI of PE added Irganox 1010 is the highest among those of PE added hindered phenol antioxidant Irganox 1076, Irganox 1010 or Irganox 1098 separately.The YI of PE added Irganox PS802 is lower than that of PE added Irgafos 168.Commonly, hindered phenol antioxidants are more effective than hydroperoxide decomposer antioxidants in preventing PE from radiation-induced coloration.The role of HALS and antioxidants played in preventing PE from radiation-induced coloration is discussed.
2001, 18(7): 552-555
Abstract:
The Zn(Ⅱ) and Cd(Ⅱ) doped nanosize PbTiO3 powders have been prepared by a sol-gel method from titanium oxyoxalate, citric acid, lead acetate, zine acetate or cadmium oxalate and characterized by XRD and TEM.Their catalytic activities for photocatalytic degradation of reactive turquoise blue K-GL was found to be greater than that of pure PbTiO3 powder, whereas the PbTiO3 doped with 5%(mole fraction) of Zn(Ⅱ) and Cd(Ⅱ) showed the greatest catalytic activity.The activity of Zn(Ⅱ) doped PbTiO 3 is higher than that of Cd(Ⅱ) doped one, likely due to the small radius of zinc ion which induced distortion of the lattice.The optimum pH value of the solution for photodegradation appeared less than 10.
The Zn(Ⅱ) and Cd(Ⅱ) doped nanosize PbTiO3 powders have been prepared by a sol-gel method from titanium oxyoxalate, citric acid, lead acetate, zine acetate or cadmium oxalate and characterized by XRD and TEM.Their catalytic activities for photocatalytic degradation of reactive turquoise blue K-GL was found to be greater than that of pure PbTiO3 powder, whereas the PbTiO3 doped with 5%(mole fraction) of Zn(Ⅱ) and Cd(Ⅱ) showed the greatest catalytic activity.The activity of Zn(Ⅱ) doped PbTiO 3 is higher than that of Cd(Ⅱ) doped one, likely due to the small radius of zinc ion which induced distortion of the lattice.The optimum pH value of the solution for photodegradation appeared less than 10.
2001, 18(7): 556-559
Abstract:
An optical capillary rheometer has been fabricated with capillary diameter ranged from 50μm to 200μm.On the rheometer extremely low shear rates(1~5 s-1) for polyacrylamide soltion can be recorded.The results showed that at extremely low shear rates PAM solution behaves as a Bingham solution and the concentration and temperature show great effects on the non-Newtonian index, consistency coefficient, yield shear stress and apparent viscosity of the PAM solution.
An optical capillary rheometer has been fabricated with capillary diameter ranged from 50μm to 200μm.On the rheometer extremely low shear rates(1~5 s-1) for polyacrylamide soltion can be recorded.The results showed that at extremely low shear rates PAM solution behaves as a Bingham solution and the concentration and temperature show great effects on the non-Newtonian index, consistency coefficient, yield shear stress and apparent viscosity of the PAM solution.
2001, 18(7): 560-562
Abstract:
The meso-tetra(T,T,T,T-O-phenylacetylbenzene)porphyrin was used as a complete antigen to elicit monoclonal antibody 1F2 through the immunization and cell fusion techniques.The antibody could combine with Mn porphyrin and showed a haloperoxidase activity.The affinities of the antibody for antigen and Mn porphyrin were 4.98×10-5 mol/L and 7.63×10-5 mol/L, respectively.When the antibody-Mn porphyrin complex was used to catalyze the halogenation reaction, the Michaelis constant and reactive rate constant κcat for H2O2 were 5.127 0×10-3 mol/L and 0.4834 s-1, respectively.The enzyme exchange number κcat/Km=94.2851 mol/(L·s).
The meso-tetra(T,T,T,T-O-phenylacetylbenzene)porphyrin was used as a complete antigen to elicit monoclonal antibody 1F2 through the immunization and cell fusion techniques.The antibody could combine with Mn porphyrin and showed a haloperoxidase activity.The affinities of the antibody for antigen and Mn porphyrin were 4.98×10-5 mol/L and 7.63×10-5 mol/L, respectively.When the antibody-Mn porphyrin complex was used to catalyze the halogenation reaction, the Michaelis constant and reactive rate constant κcat for H2O2 were 5.127 0×10-3 mol/L and 0.4834 s-1, respectively.The enzyme exchange number κcat/Km=94.2851 mol/(L·s).
2001, 18(7): 563-565
Abstract:
The dissolution enthalpies of the[Sm(NO3)3·6H2O(s)+4Ala(s)] and Sm(Ala)4(NO3)3·H2O(s) have been measured at 298.15 K using a homemade isoperibolic calorimeter with hydrochloric acid solution(2 mol/L) as solvent.The standard molar enthalpy of the coodination reaction of alanine with samarium nitrate has been determined via a designed thermochemical cycle, and ΔHr,mθ=21.393 kJ/mol was obtained.The standard molar enthalpy of formation of the complex Sm(Ala)4-(NO3)3·H2O has been calculated to be ΔHf,mθ [Sm(Ala)4(NO3)3·H2O,s,298.15 K]=-3 865.2 kJ/mol.
The dissolution enthalpies of the[Sm(NO3)3·6H2O(s)+4Ala(s)] and Sm(Ala)4(NO3)3·H2O(s) have been measured at 298.15 K using a homemade isoperibolic calorimeter with hydrochloric acid solution(2 mol/L) as solvent.The standard molar enthalpy of the coodination reaction of alanine with samarium nitrate has been determined via a designed thermochemical cycle, and ΔHr,mθ=21.393 kJ/mol was obtained.The standard molar enthalpy of formation of the complex Sm(Ala)4-(NO3)3·H2O has been calculated to be ΔHf,mθ [Sm(Ala)4(NO3)3·H2O,s,298.15 K]=-3 865.2 kJ/mol.
2001, 18(7): 566-568
Abstract:
An efficient one-pot synthesis method for 3,4-dihydropyrimidinones using lanthanum chloride heptahydrate as a catalyst by the reaction of aldehyde, U-keto ester and urea(in molar ratio 1:1:1.5) in ethanol is described.The method is simple and affords product in good yield(80%~90%).
An efficient one-pot synthesis method for 3,4-dihydropyrimidinones using lanthanum chloride heptahydrate as a catalyst by the reaction of aldehyde, U-keto ester and urea(in molar ratio 1:1:1.5) in ethanol is described.The method is simple and affords product in good yield(80%~90%).
2001, 18(7): 569-571
Abstract:
Nine 10-arylidene anthrones were synthesized from anthrone and aryl aldehydes in xylene using pyridine as catalyst and p-t-butylphenol as an antioxidant.The higher yields of the nine title compounds were achieved due to adding p-t-butylphenol in the reaction system which could significantly avoid formation of anthraquinone, the main by-product of the reaction, leading a troublesome procedure for product purification.
Nine 10-arylidene anthrones were synthesized from anthrone and aryl aldehydes in xylene using pyridine as catalyst and p-t-butylphenol as an antioxidant.The higher yields of the nine title compounds were achieved due to adding p-t-butylphenol in the reaction system which could significantly avoid formation of anthraquinone, the main by-product of the reaction, leading a troublesome procedure for product purification.
2001, 18(7): 572-574
Abstract:
N,N'-Ditosyl-1,5-diazacycloheptan-3-one(2) and its derivatives(3b~3d) have been synthesized from 1,3-dichloro-2-propanol and N,N'-ditosylethylenediamine via cyclization, oxidation and substitution.All the new compounds(2 and 3a~3d) have been characterized by IR, 1H NMR, MS and elemental analysis.The reactions of all steps are carried out under moderate conditions with the overall yield 27%~30%.
N,N'-Ditosyl-1,5-diazacycloheptan-3-one(2) and its derivatives(3b~3d) have been synthesized from 1,3-dichloro-2-propanol and N,N'-ditosylethylenediamine via cyclization, oxidation and substitution.All the new compounds(2 and 3a~3d) have been characterized by IR, 1H NMR, MS and elemental analysis.The reactions of all steps are carried out under moderate conditions with the overall yield 27%~30%.
2001, 18(7): 575-577
Abstract:
A simple electrode preparation method is reported, based on the adsorption of poly-lysine on the surface of the gold electrode to immobilize CT-DNA through the electrostatic action.The DNA modified electrode is stable during a 100 continuous cyclic voltammetric measurement.
A simple electrode preparation method is reported, based on the adsorption of poly-lysine on the surface of the gold electrode to immobilize CT-DNA through the electrostatic action.The DNA modified electrode is stable during a 100 continuous cyclic voltammetric measurement.
2001, 18(7): 578-580
Abstract:
The flocculating property of chitosan on medicinal bentonite suspension has been investigaeted.Some factors such as deacetylation degree and concentration of chitosan and pH were examined.The results showed that chitosan has the flocculating property superior to cationic type plolyacrylamide.The adsorption capacity of medicinal bentonite suspension obtained from chitosan flocculation only has a little change as compared with common medicinal bentonite suspension.
The flocculating property of chitosan on medicinal bentonite suspension has been investigaeted.Some factors such as deacetylation degree and concentration of chitosan and pH were examined.The results showed that chitosan has the flocculating property superior to cationic type plolyacrylamide.The adsorption capacity of medicinal bentonite suspension obtained from chitosan flocculation only has a little change as compared with common medicinal bentonite suspension.
2001, 18(7): 581-583
Abstract:
3,4,5-Trimethoxybenzaldehyde was synthesized from p-cresol in an overall yield of 64 5%.p-Cresol was at first brominated and hydrolyzed to give 3,5-dibromo-4-hydroxybenzal-dehyde, which was methoxylated by methanolic sodium methoxide in the presence of cuprous chloride and dimethylformamide(DMF) at 125℃(ca.0.5 MPa) to provide sodium phenolate of 3,5-dimethoxy-4-hydroxybenzaldehyde, from which 3,4,5-trimethoxybenzaldehyde was obtained by methylation directly with dimethyl sulfate in aqueous sodium hydroxide."One-pot" method was used in the synthesis starting from economical, convenient and environmental awareness.
3,4,5-Trimethoxybenzaldehyde was synthesized from p-cresol in an overall yield of 64 5%.p-Cresol was at first brominated and hydrolyzed to give 3,5-dibromo-4-hydroxybenzal-dehyde, which was methoxylated by methanolic sodium methoxide in the presence of cuprous chloride and dimethylformamide(DMF) at 125℃(ca.0.5 MPa) to provide sodium phenolate of 3,5-dimethoxy-4-hydroxybenzaldehyde, from which 3,4,5-trimethoxybenzaldehyde was obtained by methylation directly with dimethyl sulfate in aqueous sodium hydroxide."One-pot" method was used in the synthesis starting from economical, convenient and environmental awareness.
2001, 18(7): 584-586
Abstract:
A complex additive has been synthesized from maleic acid, sodium hypophosphite and Zn2+ dodecyl-polyglucoside.It was used to prepare α-FeOOH by alkaline method with different concentration of additive oxidation of Fe2+ has been discussed.The result showed that particle pattern of α-FeOOH was better when additive concentration was 1.0×10-3 g/L.The V-Fe2O3 powder with perfect comprehensive quality was prepared from α-FeOOH by dehydration, roast, reduction and oxidation.
A complex additive has been synthesized from maleic acid, sodium hypophosphite and Zn2+ dodecyl-polyglucoside.It was used to prepare α-FeOOH by alkaline method with different concentration of additive oxidation of Fe2+ has been discussed.The result showed that particle pattern of α-FeOOH was better when additive concentration was 1.0×10-3 g/L.The V-Fe2O3 powder with perfect comprehensive quality was prepared from α-FeOOH by dehydration, roast, reduction and oxidation.
2001, 18(7): 587-588
Abstract:
TSA(toluene-p-sulfonic acid) doped polyaniline was prepared potentiostatically(0.5 V vs.SCE) on Pt electrode in an electrolyte solution containing 0.3 mol/L An and 0.45 mol/L TSA and investigated by cyclic voltammetry, thermal stability and solubility experimentats.The results show that the TSA doped PAn has a good redox reversibility in H2SO4 medium with temperature of thermal decomposition being 248.5℃ and soluble in NMP, aMF and DMSO.
TSA(toluene-p-sulfonic acid) doped polyaniline was prepared potentiostatically(0.5 V vs.SCE) on Pt electrode in an electrolyte solution containing 0.3 mol/L An and 0.45 mol/L TSA and investigated by cyclic voltammetry, thermal stability and solubility experimentats.The results show that the TSA doped PAn has a good redox reversibility in H2SO4 medium with temperature of thermal decomposition being 248.5℃ and soluble in NMP, aMF and DMSO.
2001, 18(7): 589-591
Abstract:
(±)-Frontalin (1,5-dimethyl-6,8-dioxabicycl octane), an aggregation pheromone of bark beetle, was prepared from cyclohexanone via a key intermediate 6-hepten-2-one prepared by catalytic decarbonylation of 7-oxo-octanoic acid with acetic anhydride using palladium(Ⅱ) complex as catalyst.The structures of all the compounds were confirmed by IR, MS, 1H NMR and 13C NMR.
(±)-Frontalin (1,5-dimethyl-6,8-dioxabicycl octane), an aggregation pheromone of bark beetle, was prepared from cyclohexanone via a key intermediate 6-hepten-2-one prepared by catalytic decarbonylation of 7-oxo-octanoic acid with acetic anhydride using palladium(Ⅱ) complex as catalyst.The structures of all the compounds were confirmed by IR, MS, 1H NMR and 13C NMR.
2001, 18(7): 592-594
Abstract:
Starch acetate with high DS was prepared by glacial acetic acid and acetic anhydride using methyl sulfonic acid as a catalyst.The influences of reaction temperature, reaction time, ratios of reactants on the esterification have been examined.The product is characterized by chemical analysis, infrared analysis, intrinsic viscosity and solubility measurements.High linear amylose was found easier to be esterized.
Starch acetate with high DS was prepared by glacial acetic acid and acetic anhydride using methyl sulfonic acid as a catalyst.The influences of reaction temperature, reaction time, ratios of reactants on the esterification have been examined.The product is characterized by chemical analysis, infrared analysis, intrinsic viscosity and solubility measurements.High linear amylose was found easier to be esterized.
