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2006 Volume 23 Issue 8
2006, 23(8): 821-825
Abstract:
Seventeen resins were selected to compare their performances in adsorbing and desorbing monosubstituent in the mixture.Experimental results showed that HZ-841 resin possessed higher selectivity and desorption capacity.The adsorption characteristic of monosubstituent on HZ-841 resin was determined.The adsorption isotherms,kinetic curves,breakthrough curves and elution curves were determined.The adsorption isotherms were Langmuir type.The adsorption kinetic curve could be preferably described by the second-order Lagergren equation,and the adsorption equilibrium was achieved in about 5 h.On a column of Φ 16 mm×400 mm,the breakthrough volume of CD was 200 mL when the mixture concentration was 4.8 g/L,the flow rate was 2.5 mL/min,while that of monosubstituent was 1 130 mL.The adsorbate was completely eluted with 700 mL of hot(90℃) water,and the desorption rates were 98.1% and 94.9% for β-cyclodextrin and monosubstituent,respectively.
Seventeen resins were selected to compare their performances in adsorbing and desorbing monosubstituent in the mixture.Experimental results showed that HZ-841 resin possessed higher selectivity and desorption capacity.The adsorption characteristic of monosubstituent on HZ-841 resin was determined.The adsorption isotherms,kinetic curves,breakthrough curves and elution curves were determined.The adsorption isotherms were Langmuir type.The adsorption kinetic curve could be preferably described by the second-order Lagergren equation,and the adsorption equilibrium was achieved in about 5 h.On a column of Φ 16 mm×400 mm,the breakthrough volume of CD was 200 mL when the mixture concentration was 4.8 g/L,the flow rate was 2.5 mL/min,while that of monosubstituent was 1 130 mL.The adsorbate was completely eluted with 700 mL of hot(90℃) water,and the desorption rates were 98.1% and 94.9% for β-cyclodextrin and monosubstituent,respectively.
2006, 23(8): 826-829
Abstract:
An Alizarin-Cu(Ac)2-imprinted polymer was synthesized based on copper ion coordination with the monomer.The binding experiments showed that the polymer exhibited a higher binding capacity for Alizarin-copper acetate and had no affinity for its structural analogues.Scatchard analysis showed that one type of binding sites was formed in the imprinted polymer in the studied concentration range.The dissociation constant and the apparent maximum number of the binding sites were calculated to be 0.80 mmol/L and 52.68 μmol/g,respectively,and the maximum template selective site was 21.26 μmol/g.Changing the acetate to other anions resulted in the loss of imprinting effect,suggesting that the complex formed prior to the polymerization was composed of copper(Ⅱ),acetate,Alizarin and 2-vinylprindine.
An Alizarin-Cu(Ac)2-imprinted polymer was synthesized based on copper ion coordination with the monomer.The binding experiments showed that the polymer exhibited a higher binding capacity for Alizarin-copper acetate and had no affinity for its structural analogues.Scatchard analysis showed that one type of binding sites was formed in the imprinted polymer in the studied concentration range.The dissociation constant and the apparent maximum number of the binding sites were calculated to be 0.80 mmol/L and 52.68 μmol/g,respectively,and the maximum template selective site was 21.26 μmol/g.Changing the acetate to other anions resulted in the loss of imprinting effect,suggesting that the complex formed prior to the polymerization was composed of copper(Ⅱ),acetate,Alizarin and 2-vinylprindine.
2006, 23(8): 830-834
Abstract:
A new method is presented for nickel nanowire deposition in porous anodic alumina(PAA) template by direct current.The barrier layer of PAA was removed by electrolysis in neutral potassium chloride solution with the PAA as the cathode.The electrochemical behavior of Nickel ion and hydrogen ion on PAA was studied by measuring the polarization curves.The morphology and the crystal structure of the PAA and the nickel nanowires were characterized by SEM and XRD.The cyclic voltammogram of the PAA with the barrier layer eroded showed an oxidation peak in the first scan in a 0.5 mol/L phosphate buffer solution.The deposition potential of nickel ions on PAA was -1.0 V versus Ag/AgCl.The diameter of the nanowires was about 70~80 nm based on SEM.XRD showed that the deposited material was cubic nickel orienting along the (111) direction.After the barrier layer was eroded,PAA could be used directly as a template to fabricate nickel nanowire by direct current method.
A new method is presented for nickel nanowire deposition in porous anodic alumina(PAA) template by direct current.The barrier layer of PAA was removed by electrolysis in neutral potassium chloride solution with the PAA as the cathode.The electrochemical behavior of Nickel ion and hydrogen ion on PAA was studied by measuring the polarization curves.The morphology and the crystal structure of the PAA and the nickel nanowires were characterized by SEM and XRD.The cyclic voltammogram of the PAA with the barrier layer eroded showed an oxidation peak in the first scan in a 0.5 mol/L phosphate buffer solution.The deposition potential of nickel ions on PAA was -1.0 V versus Ag/AgCl.The diameter of the nanowires was about 70~80 nm based on SEM.XRD showed that the deposited material was cubic nickel orienting along the (111) direction.After the barrier layer was eroded,PAA could be used directly as a template to fabricate nickel nanowire by direct current method.
2006, 23(8): 835-839
Abstract:
Polyamidoamine dendrimers(PAMAM) of 1~2 generations(1.0G~2.0G PAMAM) were synthesized via the divergent procedure,we synthesized and the dendritic PAMAMMMAZO liquid crystal polymer was synthesized by Michael addition at room temperature under normal pressure.LC,IR,and 1H NMR revealed that the target polymers were succesfully prepared.The liquid-crystalline behavior of the synthesized copolymers was evidenced from POM and DSC observation.The yield of the products was 45% with a purity over 90%.The copolymers exhibit different liquid crystalline behavior compared to MMAZO.
Polyamidoamine dendrimers(PAMAM) of 1~2 generations(1.0G~2.0G PAMAM) were synthesized via the divergent procedure,we synthesized and the dendritic PAMAMMMAZO liquid crystal polymer was synthesized by Michael addition at room temperature under normal pressure.LC,IR,and 1H NMR revealed that the target polymers were succesfully prepared.The liquid-crystalline behavior of the synthesized copolymers was evidenced from POM and DSC observation.The yield of the products was 45% with a purity over 90%.The copolymers exhibit different liquid crystalline behavior compared to MMAZO.
2006, 23(8): 840-844
Abstract:
The interactions between polymer and each of four kinds of surfactants were studied by means of a controlled-stress rheometer.It was found that there was a strong interaction between the cationic surfactant CTAB and HPAM.At low concentrations,the storage modulus of the complex system compared with its initial value could increase by 20%~35%,while at high concentrations it decreased significantly.The anionic surfactant-sodium dodecyl sulphate(SDS) concentration showed a pronounced effect on the rheological properties of the SDS/HPAM system.At low concentrations,the storage modulus of the complex system increased with a critical concentration between 500 mg/L and 1 000 mg/L,then it decreased when further increasing SDS concentration due to the electrolyte effect.When nonionic and amphoteric surfactants were interacted with HPAM,the storage modulus of the complex systems increased with increasing their concentrations.
The interactions between polymer and each of four kinds of surfactants were studied by means of a controlled-stress rheometer.It was found that there was a strong interaction between the cationic surfactant CTAB and HPAM.At low concentrations,the storage modulus of the complex system compared with its initial value could increase by 20%~35%,while at high concentrations it decreased significantly.The anionic surfactant-sodium dodecyl sulphate(SDS) concentration showed a pronounced effect on the rheological properties of the SDS/HPAM system.At low concentrations,the storage modulus of the complex system increased with a critical concentration between 500 mg/L and 1 000 mg/L,then it decreased when further increasing SDS concentration due to the electrolyte effect.When nonionic and amphoteric surfactants were interacted with HPAM,the storage modulus of the complex systems increased with increasing their concentrations.
2006, 23(8): 845-849
Abstract:
Complexes Eu(OPri)(TTA)2,Tb(OPri)(TTA)2 and Sm (OPri)(TTA)2 were synthesized by replacing partial isopropoxyl group with thenoyltrifluoroacetone(TTA) under the protection of N2.The photoluminescent organic glass materials containing these complexes were prepared via the bulk polymerization of methyl methacrylate(MMA)/complex blends.The polymers containing these complexes were characterized by means of elemental analysis,FT-IR,XRD and FS.There existed interaction between the rare earth ions and the carboxyl group of MMA monomer.The organic glass materials containing Eu(OPri)-(TTA)2,Tb(OPri)(TTA)2 or Sm (OPri)(TTA)2 exhibited strong characteristic luminescence of Eu3+(613 nm),Tb3+(544 nm) or Sm3+(644 nm) under excitation at the most suitable wavelength for each compound, respectively.Their luminescent intensities were as high as that of PMMA containing Re(TTA)3.In addition,the organic glass materials were amorphous and exhibited high solubility and transparence.
Complexes Eu(OPri)(TTA)2,Tb(OPri)(TTA)2 and Sm (OPri)(TTA)2 were synthesized by replacing partial isopropoxyl group with thenoyltrifluoroacetone(TTA) under the protection of N2.The photoluminescent organic glass materials containing these complexes were prepared via the bulk polymerization of methyl methacrylate(MMA)/complex blends.The polymers containing these complexes were characterized by means of elemental analysis,FT-IR,XRD and FS.There existed interaction between the rare earth ions and the carboxyl group of MMA monomer.The organic glass materials containing Eu(OPri)-(TTA)2,Tb(OPri)(TTA)2 or Sm (OPri)(TTA)2 exhibited strong characteristic luminescence of Eu3+(613 nm),Tb3+(544 nm) or Sm3+(644 nm) under excitation at the most suitable wavelength for each compound, respectively.Their luminescent intensities were as high as that of PMMA containing Re(TTA)3.In addition,the organic glass materials were amorphous and exhibited high solubility and transparence.
2006, 23(8): 850-853
Abstract:
Dibutyl phthalate hapten(dibutyl 4-aminophthalate) was synthesized by introducing amino group as a substituent at the aromatic ring while retaining the ester group.The product was characterized by means of 1H NMR,IR and UV,with λ1=212 nm,λ2=258 nm for the UV of dibutyl 4-nitrophthalate and λ1=226 nm,λ2=288 nm for the UV of dibutyl 4-aminophthalate.The hapten was conjugated to BSA via amino diazotization linkage.Thus artificial antigen was prepared and tested by fluorescence spectrum with λex=307 nm,λem=468 nm,and the approximate molar ratio of dibutyl 4-aminophthalate to BSA was 13.The product was used as an immunogen,demonstrating that it is suitable for polyclonal antibody production.The present research has supplied an excellent immune antigen for further preparation and immunoassay of antibody obtained from dibutyl phthalate.
Dibutyl phthalate hapten(dibutyl 4-aminophthalate) was synthesized by introducing amino group as a substituent at the aromatic ring while retaining the ester group.The product was characterized by means of 1H NMR,IR and UV,with λ1=212 nm,λ2=258 nm for the UV of dibutyl 4-nitrophthalate and λ1=226 nm,λ2=288 nm for the UV of dibutyl 4-aminophthalate.The hapten was conjugated to BSA via amino diazotization linkage.Thus artificial antigen was prepared and tested by fluorescence spectrum with λex=307 nm,λem=468 nm,and the approximate molar ratio of dibutyl 4-aminophthalate to BSA was 13.The product was used as an immunogen,demonstrating that it is suitable for polyclonal antibody production.The present research has supplied an excellent immune antigen for further preparation and immunoassay of antibody obtained from dibutyl phthalate.
2006, 23(8): 854-857
Abstract:
A new betaine-type zwitterionic compound with a long hydrophilic carbon chain,(9-carboxy-nonyl)-dimethyl-[2-methyl-acryloyloxy]-ethyl]-ammonium bromide(CNDMAM),was synthesized from DMand 10-Bromodecanoic Acid.An optimal yield of 78% was achieved when the reaction was carried out with n(DM):n(10-Bromodecanoic Acid)=2:1 at 55℃ for 8 h.The structure of the product was confirmed by1H NMR,FT-IR,titration,and melting point measurement.(9-Carboxy-nonyl)-dimethyl-[2-methyl-acryloy-loxy]-ethyl]-ammonium bromide was copolymerized with AMand the copolymer was characterized by FT-IR.
A new betaine-type zwitterionic compound with a long hydrophilic carbon chain,(9-carboxy-nonyl)-dimethyl-[2-methyl-acryloyloxy]-ethyl]-ammonium bromide(CNDMAM),was synthesized from DMand 10-Bromodecanoic Acid.An optimal yield of 78% was achieved when the reaction was carried out with n(DM):n(10-Bromodecanoic Acid)=2:1 at 55℃ for 8 h.The structure of the product was confirmed by1H NMR,FT-IR,titration,and melting point measurement.(9-Carboxy-nonyl)-dimethyl-[2-methyl-acryloy-loxy]-ethyl]-ammonium bromide was copolymerized with AMand the copolymer was characterized by FT-IR.
2006, 23(8): 858-861
Abstract:
The electrochemical behavior of sulfadiazine(SD) at multi-wall carbon nanotube(MWNT) modified glassy carbon electrode(GCE) was investigated.The peak current of SD at the MWNT-modified GCE increased significantly in comparison with that at the bare GCE.Based on this,a direct electroanalytical method for determining SD was developed.The experimental parameters such as buffer pH,accumulation potential and time,the amount of MWNT onto the electrode surface and scan rate were optimized.The oxidation peak current increased linearly with the concentration of SD in the range of 1.0×10-6~1.2×10-4 moL/L.The detection limit was 5.0×10-7 mol/L.With the proposed method,SD in sulfadiazine tablets was determined.
The electrochemical behavior of sulfadiazine(SD) at multi-wall carbon nanotube(MWNT) modified glassy carbon electrode(GCE) was investigated.The peak current of SD at the MWNT-modified GCE increased significantly in comparison with that at the bare GCE.Based on this,a direct electroanalytical method for determining SD was developed.The experimental parameters such as buffer pH,accumulation potential and time,the amount of MWNT onto the electrode surface and scan rate were optimized.The oxidation peak current increased linearly with the concentration of SD in the range of 1.0×10-6~1.2×10-4 moL/L.The detection limit was 5.0×10-7 mol/L.With the proposed method,SD in sulfadiazine tablets was determined.
2006, 23(8): 862-865
Abstract:
Using an AlCl3/SbCl3binary catalyst,a mixture of α-pinene and β-pinene was polymerized to produce,a copolymer of α-pinene and β-pinene with a softening point of 136.0℃ and a color grade of 3(Fe-Co) with a yield of more than 85.7% under the following conditions:polymerization temperature 0℃;m(α-pinene):m(β-pinene)=5:5;addition rates of α-pinene,β-pinene and SbCl3all being 4.0 mL/min;ω(AlCl3)=3.0% and AlCl3 powder of 0.17~0.61 mm size;m(SbCl3)/m(AlCl3)=0.50;holding time 4.0 h.The copolymer was also characterized by solubility,GPC,ozonization,UV,IR and13C NMR.
Using an AlCl3/SbCl3binary catalyst,a mixture of α-pinene and β-pinene was polymerized to produce,a copolymer of α-pinene and β-pinene with a softening point of 136.0℃ and a color grade of 3(Fe-Co) with a yield of more than 85.7% under the following conditions:polymerization temperature 0℃;m(α-pinene):m(β-pinene)=5:5;addition rates of α-pinene,β-pinene and SbCl3all being 4.0 mL/min;ω(AlCl3)=3.0% and AlCl3 powder of 0.17~0.61 mm size;m(SbCl3)/m(AlCl3)=0.50;holding time 4.0 h.The copolymer was also characterized by solubility,GPC,ozonization,UV,IR and13C NMR.
2006, 23(8): 866-870
Abstract:
The interaction between theophylline and bovine serum albumin(BSA) was investigated via fluorescence spectroscopy.The experimental results show that the fluorescence quenching of BSA by theophylline is due to the formation of theophylline-BSA complex through both static quenching and nonradiative energy transfer. The binding site number n and the apparent binding constant KA were measured;the binding distance r and the energy transfer efficiency E between theophylline and BSA were obtained according to fluorescence resonance energy transfer;the effect of theophylline on the conformation of BSA was analyzed by means of synchronous fluorescence spectroscopy.
The interaction between theophylline and bovine serum albumin(BSA) was investigated via fluorescence spectroscopy.The experimental results show that the fluorescence quenching of BSA by theophylline is due to the formation of theophylline-BSA complex through both static quenching and nonradiative energy transfer. The binding site number n and the apparent binding constant KA were measured;the binding distance r and the energy transfer efficiency E between theophylline and BSA were obtained according to fluorescence resonance energy transfer;the effect of theophylline on the conformation of BSA was analyzed by means of synchronous fluorescence spectroscopy.
2006, 23(8): 871-874
Abstract:
The chemical composition of Oldenlandia cantonensis How,a herbal medicine is reported.A new pentacyclic triterpenoid,urs-12-en-29α-oic acid-3β-ol was obtained from the EtOAc-eluted fraction of the ethanol extract of Oldenlandia cantonensis How.The structure was elucidated by spectroscopy methods, including NMR(1D and 2D),IR,and MS.Urs-12-en-29α-oic acid-3β-ol exhibited potent inhibiting effect against the human DNA topoisomerase Ⅰ(hTopo Ⅰ),the cancer cell lines BEL-7402,and MCG-803, with the IC50 values 12.0×10-6,6.5×10-6 and 8.0×10-6 g/mL,respectively.The low polarity fatty oil,the eluted fraction of V(petroleum ether):V(EtOAc)=20:1 was also quantitatively analyzed by gas chromato-graphy mass spectrometry(GC-MS).As a result,60 compounds were detected.The fatty oil mainly composed of long chain aliphatics,terpene and steroid compounds,with percentages of 36.16%,6.42% and 9.28%,respectively.
The chemical composition of Oldenlandia cantonensis How,a herbal medicine is reported.A new pentacyclic triterpenoid,urs-12-en-29α-oic acid-3β-ol was obtained from the EtOAc-eluted fraction of the ethanol extract of Oldenlandia cantonensis How.The structure was elucidated by spectroscopy methods, including NMR(1D and 2D),IR,and MS.Urs-12-en-29α-oic acid-3β-ol exhibited potent inhibiting effect against the human DNA topoisomerase Ⅰ(hTopo Ⅰ),the cancer cell lines BEL-7402,and MCG-803, with the IC50 values 12.0×10-6,6.5×10-6 and 8.0×10-6 g/mL,respectively.The low polarity fatty oil,the eluted fraction of V(petroleum ether):V(EtOAc)=20:1 was also quantitatively analyzed by gas chromato-graphy mass spectrometry(GC-MS).As a result,60 compounds were detected.The fatty oil mainly composed of long chain aliphatics,terpene and steroid compounds,with percentages of 36.16%,6.42% and 9.28%,respectively.
2006, 23(8): 875-880
Abstract:
Photo-degradabilities,structures and degradation principles of photo-biodegradable plastic films containing 35% of corn starch were investigated by using FTIR,DSC,GPC and GC-MS.The experiment results show that the degradation rate could be regulated through different sensitizer and its content.Iron stearic and cerium stearic have the same photosensitive action on the film,which is better than that of diethyl iron dithiocarbamate.A suitable sensitizer concentration is about 0.2%~0.3%.With increasing the degree of degradation,the carbonyl index and crystallinity of polyethylene in films increase,but the melting point and relative molecular weight of polyethylene in films decrease.Some low molecular weight products,such as alkyl hydrocarbon,ketone,aldehyde,ester,carboxylic acid and binary carboxylic acid were detected in the degraded films.
Photo-degradabilities,structures and degradation principles of photo-biodegradable plastic films containing 35% of corn starch were investigated by using FTIR,DSC,GPC and GC-MS.The experiment results show that the degradation rate could be regulated through different sensitizer and its content.Iron stearic and cerium stearic have the same photosensitive action on the film,which is better than that of diethyl iron dithiocarbamate.A suitable sensitizer concentration is about 0.2%~0.3%.With increasing the degree of degradation,the carbonyl index and crystallinity of polyethylene in films increase,but the melting point and relative molecular weight of polyethylene in films decrease.Some low molecular weight products,such as alkyl hydrocarbon,ketone,aldehyde,ester,carboxylic acid and binary carboxylic acid were detected in the degraded films.
2006, 23(8): 881-885
Abstract:
Hydrophilic cellulose ester membranes were used to demulsify oil-in-water emulsions.The results indicate that a hydrophilic membrane can be used for the demulsification of oil-in-water(O/W) emulsions,and the demulsification efficiency can reach 67% at a transmembrane pressure of 0.3 MPa,a membrane pore size of 0.45 μm and a volumetric ratio of aqueous phase to internal oil phase of 4:1.Correspondingly,the effects of membrane fouling and cleaning were discussed,and about 80% flow resistance can be eliminated with a chemical abluent and compressed air.A demulsification mechanism was proposed.
Hydrophilic cellulose ester membranes were used to demulsify oil-in-water emulsions.The results indicate that a hydrophilic membrane can be used for the demulsification of oil-in-water(O/W) emulsions,and the demulsification efficiency can reach 67% at a transmembrane pressure of 0.3 MPa,a membrane pore size of 0.45 μm and a volumetric ratio of aqueous phase to internal oil phase of 4:1.Correspondingly,the effects of membrane fouling and cleaning were discussed,and about 80% flow resistance can be eliminated with a chemical abluent and compressed air.A demulsification mechanism was proposed.
2006, 23(8): 886-891
Abstract:
In a weak acidic NaH2PO4-Na2HPO4 buffer medium,cetyltrimethyl ammonium bromide(CTAB) reacts with evans blue(EB) or trypan blue(TB) to form an ion-association complex.The colors of solutions fade obviously,and the maximum fading wavelength is at 610 nm and 602 nm,respectively.The absorption intensity decrease is also proportional to the CTAB concentration.Based on this a sensitive spectrophotometric method was developed for the determination of cetyltrimethyl ammonium bromide.In the CTAB concentration range of 0~3.36×10-5 mol/L(EB-CTAB system) and 0~3.91×10-5(TB-CTAB system) the UV absorption followed Beer' law at the maximum fading wavelength;the apparent molar absorptivity ε was 1.25×104 L/(mol·cm) and 8.61×103 L/(mol·cm) respectively,with the detection limit of 7.4×10-7 mol/L and 9.1×10-7 mol/L respectively.The method has a high sensitivity and a fairly good selectivity,and was applied to the determination of CTAB in water samples with satisfactory results.In addition,the ion-association complex formation mechanism was studied using the density functional theory method of quantum chemistry,and the result was in good agreement with the experiment data.
In a weak acidic NaH2PO4-Na2HPO4 buffer medium,cetyltrimethyl ammonium bromide(CTAB) reacts with evans blue(EB) or trypan blue(TB) to form an ion-association complex.The colors of solutions fade obviously,and the maximum fading wavelength is at 610 nm and 602 nm,respectively.The absorption intensity decrease is also proportional to the CTAB concentration.Based on this a sensitive spectrophotometric method was developed for the determination of cetyltrimethyl ammonium bromide.In the CTAB concentration range of 0~3.36×10-5 mol/L(EB-CTAB system) and 0~3.91×10-5(TB-CTAB system) the UV absorption followed Beer' law at the maximum fading wavelength;the apparent molar absorptivity ε was 1.25×104 L/(mol·cm) and 8.61×103 L/(mol·cm) respectively,with the detection limit of 7.4×10-7 mol/L and 9.1×10-7 mol/L respectively.The method has a high sensitivity and a fairly good selectivity,and was applied to the determination of CTAB in water samples with satisfactory results.In addition,the ion-association complex formation mechanism was studied using the density functional theory method of quantum chemistry,and the result was in good agreement with the experiment data.
2006, 23(8): 892-896
Abstract:
N-salicylidenea chitosan schiff base was prepared by the method of microwave irradiation.The effects of reaction time and microwave output on the degree of condensation(DC) were studied.The product was characterized by UV,FTIR,TG/DTA,and its adsorption property was investigated.The result indicates that the rate of the formation reaction of N-salicylidene chitosan schiff base was greatly enhanced under microwave irradiation.The same degree of condensation(DC=88%) was reached with 6 min of 360 W microwave irradiation vs 6 h at 85℃ by conventional heating technique.The N-salicylidenea chitosan schiff base prepared via microwave irradiation exhibited higher adsorption capacity for metal ions than that via conventional heating technique.At 25℃,its adsorption capacity for Cu2+,Zn2+,Fe2+,Ni2+ was 90.5,78.5,10.2,26.3 mg/g,respectively.
N-salicylidenea chitosan schiff base was prepared by the method of microwave irradiation.The effects of reaction time and microwave output on the degree of condensation(DC) were studied.The product was characterized by UV,FTIR,TG/DTA,and its adsorption property was investigated.The result indicates that the rate of the formation reaction of N-salicylidene chitosan schiff base was greatly enhanced under microwave irradiation.The same degree of condensation(DC=88%) was reached with 6 min of 360 W microwave irradiation vs 6 h at 85℃ by conventional heating technique.The N-salicylidenea chitosan schiff base prepared via microwave irradiation exhibited higher adsorption capacity for metal ions than that via conventional heating technique.At 25℃,its adsorption capacity for Cu2+,Zn2+,Fe2+,Ni2+ was 90.5,78.5,10.2,26.3 mg/g,respectively.
2006, 23(8): 897-901
Abstract:
Polymer-supported Yb(NTf2)3 was prepared in this paper.As a novel heterogeneous Lewis acid catalyst,its catalytic activity was investigated for the esterification of benzoic acid with ethanol and nitration of toluene,and its recycling ability was also studied.At 80℃,the yield of esterification of benzoic acid with ethanol could reach 95% by using 10%(molar fraction) catalyst for 6 h;the conversion of toluene in the nitration with 1 equiv.of 65%(mass ratio) nitric acid could be achieved to 99% by using 5%(molar fraction) catalyst for 5 h.
Polymer-supported Yb(NTf2)3 was prepared in this paper.As a novel heterogeneous Lewis acid catalyst,its catalytic activity was investigated for the esterification of benzoic acid with ethanol and nitration of toluene,and its recycling ability was also studied.At 80℃,the yield of esterification of benzoic acid with ethanol could reach 95% by using 10%(molar fraction) catalyst for 6 h;the conversion of toluene in the nitration with 1 equiv.of 65%(mass ratio) nitric acid could be achieved to 99% by using 5%(molar fraction) catalyst for 5 h.
2006, 23(8): 902-906
Abstract:
Enzymatic hydrolysis of safflower oil catalyzed by a lipase from Aspergillus niger was investigated in a solvent-free system,and the effect of reaction time on the hydrolysis was studied.In addition,the selectivity of the lipase was also examined by testing the monoglycerides content in the ester and the iodine values(Ⅳ) of the fatty acid and the ester.The experiment showed that the optimum conditions for an 1 h reaction were m(H2O):m(oil)=0.5:1,m(lipase):m(oil)=5:100,35℃,pH=7.0 and 0.2% CaCl2 and the optimum conditions for an 24 h reaction were m(H2O):m(oil)=1:1,m(lipase):m(oil)=1:100,26℃,pH=7.6 and no CaCl2.The lipase has no selectivity on either the fatty acid or the site of the ester bond on the acylglycerol.
Enzymatic hydrolysis of safflower oil catalyzed by a lipase from Aspergillus niger was investigated in a solvent-free system,and the effect of reaction time on the hydrolysis was studied.In addition,the selectivity of the lipase was also examined by testing the monoglycerides content in the ester and the iodine values(Ⅳ) of the fatty acid and the ester.The experiment showed that the optimum conditions for an 1 h reaction were m(H2O):m(oil)=0.5:1,m(lipase):m(oil)=5:100,35℃,pH=7.0 and 0.2% CaCl2 and the optimum conditions for an 24 h reaction were m(H2O):m(oil)=1:1,m(lipase):m(oil)=1:100,26℃,pH=7.6 and no CaCl2.The lipase has no selectivity on either the fatty acid or the site of the ester bond on the acylglycerol.
2006, 23(8): 907-912
Abstract:
The surface tension of a mixture of zwitterionic and anionic surfactants(dodecyl betaine and sodium dodecyl sulphate C12BE-SDS) was measured.It was found that the synergism was strong,and when the molar fraction of C12BE was about 0.6,the surface activity showed a maximum.The dynamic surface tension of the mixture of C12BE-SDS with the optimal molar composition and the non-anionic surfactant TX-10 was measured.The results show that when the molar composition of TX-10 was about 0.4 in the new mixed system(C-S-TX-10),the surface activity showed a maximum.The theory about the synergic effect of the non-ideal ternary mixture agreed well with the experimental result.
The surface tension of a mixture of zwitterionic and anionic surfactants(dodecyl betaine and sodium dodecyl sulphate C12BE-SDS) was measured.It was found that the synergism was strong,and when the molar fraction of C12BE was about 0.6,the surface activity showed a maximum.The dynamic surface tension of the mixture of C12BE-SDS with the optimal molar composition and the non-anionic surfactant TX-10 was measured.The results show that when the molar composition of TX-10 was about 0.4 in the new mixed system(C-S-TX-10),the surface activity showed a maximum.The theory about the synergic effect of the non-ideal ternary mixture agreed well with the experimental result.
2006, 23(8): 913-917
Abstract:
With chitosan and sodium chloroacetate as the reactants and water as the reaction solvent, carboxymethyl chitosan(CMC) was synthesized by a new kind of method,i.e.,low-alkali method.The dependence of the degree of substitution of the CMC on the ratio of reactants,reaction temperature,reaction time and amount of catalyst was investigated.The result shows that the best reaction conditions for synthesizing CMC with a high degree of substitution(1.68) are that the ratio of chitosan to sodium chloroacetate is 1:5, reaction temperature is 90℃,reaction time is 5 h,and the amount of catalyst is 3%.The method is much better than using an alcohol-water mixed solvent.Physicochemical properties,such as solubility,isoelectric point,moisture absorption,intrinsic viscosity,were also studied.Finally,the CMC was characterized by IR,TGA and XRD.
With chitosan and sodium chloroacetate as the reactants and water as the reaction solvent, carboxymethyl chitosan(CMC) was synthesized by a new kind of method,i.e.,low-alkali method.The dependence of the degree of substitution of the CMC on the ratio of reactants,reaction temperature,reaction time and amount of catalyst was investigated.The result shows that the best reaction conditions for synthesizing CMC with a high degree of substitution(1.68) are that the ratio of chitosan to sodium chloroacetate is 1:5, reaction temperature is 90℃,reaction time is 5 h,and the amount of catalyst is 3%.The method is much better than using an alcohol-water mixed solvent.Physicochemical properties,such as solubility,isoelectric point,moisture absorption,intrinsic viscosity,were also studied.Finally,the CMC was characterized by IR,TGA and XRD.
2006, 23(8): 918-920
Abstract:
A novel route was employed to synthesize 8-phthalimido-3,6-dioxaoctan-1-ol(3) from triethylene glycol.The experimental results show that route Ⅱ is an economical one.The total yield of 8-amino-3,6-dioxaoctanoic acid(5) by route Ⅱ is 36%.
A novel route was employed to synthesize 8-phthalimido-3,6-dioxaoctan-1-ol(3) from triethylene glycol.The experimental results show that route Ⅱ is an economical one.The total yield of 8-amino-3,6-dioxaoctanoic acid(5) by route Ⅱ is 36%.
2006, 23(8): 921-923
Abstract:
A novel UV curable multi-functional polysiloxane urethane acrylate was synthesized from TDI, PETA and hydroxyl-terminated polydimethylsiloxane.The effects of the reaction temperature and the catalyst content were investigated.The optimal conditions for the synthesis of the multi-functional polysiloxane urethane acrylate were found as follows: the second step reaction temperature 70~75℃,catalyst content about 0.1%.Photosensitivity of the multi-functional polysiloxane urethane acrylate was also studied.
A novel UV curable multi-functional polysiloxane urethane acrylate was synthesized from TDI, PETA and hydroxyl-terminated polydimethylsiloxane.The effects of the reaction temperature and the catalyst content were investigated.The optimal conditions for the synthesis of the multi-functional polysiloxane urethane acrylate were found as follows: the second step reaction temperature 70~75℃,catalyst content about 0.1%.Photosensitivity of the multi-functional polysiloxane urethane acrylate was also studied.
2006, 23(8): 924-926
Abstract:
A novel methylacryloyloxyl-ethyl perfluorooctanoate(MAEF) monomer was prepared via a two-step reaction with perfluorooctanoic acid as a starting material. The main influencing factors in each reaction were stuided with an orthogonal design of experiment,and the optimal reaction conditions of acylchloridization were n(PFOA):n(SOCl2) being 1:2,the dosage of catalyst 3.2%(relative to mass percent of PFOA),reaction temperature 70~75℃,reaction time 2 h.The average yield was 97.1%.For the esterification,the optimal reaction conditions were that n(HEMA):n(PFOC) was 1:1,PFOC addition time 2 h,reaction temperature 60~62℃, reaction time 11 h,and the average yield was 75.2%.The products were characterized by elemental analysis and FTIR.
A novel methylacryloyloxyl-ethyl perfluorooctanoate(MAEF) monomer was prepared via a two-step reaction with perfluorooctanoic acid as a starting material. The main influencing factors in each reaction were stuided with an orthogonal design of experiment,and the optimal reaction conditions of acylchloridization were n(PFOA):n(SOCl2) being 1:2,the dosage of catalyst 3.2%(relative to mass percent of PFOA),reaction temperature 70~75℃,reaction time 2 h.The average yield was 97.1%.For the esterification,the optimal reaction conditions were that n(HEMA):n(PFOC) was 1:1,PFOC addition time 2 h,reaction temperature 60~62℃, reaction time 11 h,and the average yield was 75.2%.The products were characterized by elemental analysis and FTIR.
2006, 23(8): 927-929
Abstract:
By means of electrochemical impedance spectroscopy(EIS),the impedance variation of epoxy coatings with talcum powder filler coated by stearic acid was studied. The diffusion coefficients of water through epoxy coatings with talcum powder filler coated by stearic acid with different concentrations were calculated. The experimental results show that the stearic acid-coated talcum powder filler in the epoxy coatings has a function of decreasing water diffusion coefficient.In this epoxy coating system,the talcum powder filler coated by stearic acid has a critical coating concentration(0.5%).When the coating concentration is less than the concentration,the diffusion coefficient decreases with the increase of coating concentration,while when the coating concentration is higher than the concentration,the filler influences adhesion between the coating and substrate,as a result,stearic acid can cause the loss of corrosion protection.Meanwhile,the calculations show that without coating the filler,the diffusion coefficient of water is 3.01×1010/(cm2·s-1). However,when coating concentration is 0.5%,a minimum diffusion coefficient 0.89×1010/(cm2·s-1) of water could be achieved.
By means of electrochemical impedance spectroscopy(EIS),the impedance variation of epoxy coatings with talcum powder filler coated by stearic acid was studied. The diffusion coefficients of water through epoxy coatings with talcum powder filler coated by stearic acid with different concentrations were calculated. The experimental results show that the stearic acid-coated talcum powder filler in the epoxy coatings has a function of decreasing water diffusion coefficient.In this epoxy coating system,the talcum powder filler coated by stearic acid has a critical coating concentration(0.5%).When the coating concentration is less than the concentration,the diffusion coefficient decreases with the increase of coating concentration,while when the coating concentration is higher than the concentration,the filler influences adhesion between the coating and substrate,as a result,stearic acid can cause the loss of corrosion protection.Meanwhile,the calculations show that without coating the filler,the diffusion coefficient of water is 3.01×1010/(cm2·s-1). However,when coating concentration is 0.5%,a minimum diffusion coefficient 0.89×1010/(cm2·s-1) of water could be achieved.
2006, 23(8): 930-932
Abstract:
Ionic liquid [bmim]PF6(1-butyl-3-methylimidazolium hexafluorophosphate) was synthesized andcharacterized.It was used as a plasticizer for poly(methyl methacrylate) by means of in situ radical polymerization.The glass transition temperature and the thermal stability of the PMMA samples were determined byvirtue of DSC and TG.The glass transition temperature of the polymers displayed an almost linear decrease from 105℃ to belowroom temperature (20℃) with the increase of the ionic liquid content from 0 to 60%(volume fraction),and the corresponding mass loss of PMMAdecreased from 4.19% to 0.16%.All of theseindicated that the [bmim]PF6as a plasticizer was able to reduce the glass transition temperature of PMMA and improved its thermal stability remarkably.
Ionic liquid [bmim]PF6(1-butyl-3-methylimidazolium hexafluorophosphate) was synthesized andcharacterized.It was used as a plasticizer for poly(methyl methacrylate) by means of in situ radical polymerization.The glass transition temperature and the thermal stability of the PMMA samples were determined byvirtue of DSC and TG.The glass transition temperature of the polymers displayed an almost linear decrease from 105℃ to belowroom temperature (20℃) with the increase of the ionic liquid content from 0 to 60%(volume fraction),and the corresponding mass loss of PMMAdecreased from 4.19% to 0.16%.All of theseindicated that the [bmim]PF6as a plasticizer was able to reduce the glass transition temperature of PMMA and improved its thermal stability remarkably.
2006, 23(8): 933-935
Abstract:
A novel blue fluorescence compound with two-photon property was synthesized.The structure of the compound was characterized by elemental analysis,electronspray mass spectra,1H NMR,and IR spectra.UV-Vis absorption,one-photon induced fluorescence,one-photon fluorescence quantum yield,one-photon fluorescence lifetime and two-photon induced fluorescence were experimentally studied.The two-photon absorption cross-section is as high as 17×10-50 cm4·s·photon-1.It is a potential blue emission material.
A novel blue fluorescence compound with two-photon property was synthesized.The structure of the compound was characterized by elemental analysis,electronspray mass spectra,1H NMR,and IR spectra.UV-Vis absorption,one-photon induced fluorescence,one-photon fluorescence quantum yield,one-photon fluorescence lifetime and two-photon induced fluorescence were experimentally studied.The two-photon absorption cross-section is as high as 17×10-50 cm4·s·photon-1.It is a potential blue emission material.
2006, 23(8): 936-938
Abstract:
Condensation of 2-bromo-4-fluorobenzoyl hydrazine(1) with aromatic aldehydes produced corresponding hydrazones(2a~2i).Cyclization of 2a~2i with propanoic anhydide gave the title compounds 3a~3i in good yields of 79.3%~85.5%.Their structures were characterized by means of elemental analysis,IR,1H NMR and MS spectra.The preliminary antibacterial tests showed that most of them had good antibacterial activities.
Condensation of 2-bromo-4-fluorobenzoyl hydrazine(1) with aromatic aldehydes produced corresponding hydrazones(2a~2i).Cyclization of 2a~2i with propanoic anhydide gave the title compounds 3a~3i in good yields of 79.3%~85.5%.Their structures were characterized by means of elemental analysis,IR,1H NMR and MS spectra.The preliminary antibacterial tests showed that most of them had good antibacterial activities.
2006, 23(8): 939-941
Abstract:
α-Cyclocitral(1) was used as the A-ring synthon and triphenyl phosphonium chloride(2) as the C-ring synthon,and the tricyclic structure of α,β-unsaturated ketone was constructed through the Birch reduction.Finally the target compound was synthesized by the reaction of i-PrMgBr,a Grignard reagent,with α,β-unsaturated ketone through neucleophilic addition under the catalysis of anhydrous CeCl3.The IR absorption peak at 3 418 cm-1 indicated that the hydroxyl group was introduced into the target compound successfully.In the 1H NMR spectrum,the peaks at δ0.96,1.83 and 6.98 indicate that the iso-propyl group has been bonded to C-13 in the target compound.The 13C NMR and HRMS data were consistent with the structure of the target compound.In conclusion,the target compound was successfully synthesized through the method reported in this paper.
α-Cyclocitral(1) was used as the A-ring synthon and triphenyl phosphonium chloride(2) as the C-ring synthon,and the tricyclic structure of α,β-unsaturated ketone was constructed through the Birch reduction.Finally the target compound was synthesized by the reaction of i-PrMgBr,a Grignard reagent,with α,β-unsaturated ketone through neucleophilic addition under the catalysis of anhydrous CeCl3.The IR absorption peak at 3 418 cm-1 indicated that the hydroxyl group was introduced into the target compound successfully.In the 1H NMR spectrum,the peaks at δ0.96,1.83 and 6.98 indicate that the iso-propyl group has been bonded to C-13 in the target compound.The 13C NMR and HRMS data were consistent with the structure of the target compound.In conclusion,the target compound was successfully synthesized through the method reported in this paper.
2006, 23(8): 942-944
Abstract:
Tetrandrine(Tet) and alkaloids of Stephenia tetrandra S. Moore(AST) were isolated from Chinese natural medicine of Stephenia tetrandra S. Moore.The inhibitory action of Tet and AST and the drug resistance of E. coli to Tet and AST were studied by microcalorimetric method.It was found that Tet and AST had inhibitory action on E. coli and the inhibitory action of Tet was better than that of AST.But the drug resistance of E. coli to AST was more slowly induced than that of Tet,which may be because the complicated components in AST could have a synergetic effect on inhibiting drug resistance.
Tetrandrine(Tet) and alkaloids of Stephenia tetrandra S. Moore(AST) were isolated from Chinese natural medicine of Stephenia tetrandra S. Moore.The inhibitory action of Tet and AST and the drug resistance of E. coli to Tet and AST were studied by microcalorimetric method.It was found that Tet and AST had inhibitory action on E. coli and the inhibitory action of Tet was better than that of AST.But the drug resistance of E. coli to AST was more slowly induced than that of Tet,which may be because the complicated components in AST could have a synergetic effect on inhibiting drug resistance.
