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2009 Volume 26 Issue 1
2009, 26(1): 1-6
Abstract:
The recent progress in rare-earth phosphate luminescent nanomaterials is reviewed.The preparation methods of the nanomaterials are compiled.The application and new progress in the hydrothermal synthesis method,sonochemical synthesis method,and microwave heating method etc.for the preparation of the nanomaterials are discussed in detail.The luminescent mechanism of the nanomaterials is elucidated from the microstructure viewpoint.The effects of doping of rare-earth metal ions,shell-core structure,morphology,and crystal structure on the fluorescent properties of rate-earth phosphates are extensively discussed.
The recent progress in rare-earth phosphate luminescent nanomaterials is reviewed.The preparation methods of the nanomaterials are compiled.The application and new progress in the hydrothermal synthesis method,sonochemical synthesis method,and microwave heating method etc.for the preparation of the nanomaterials are discussed in detail.The luminescent mechanism of the nanomaterials is elucidated from the microstructure viewpoint.The effects of doping of rare-earth metal ions,shell-core structure,morphology,and crystal structure on the fluorescent properties of rate-earth phosphates are extensively discussed.
2009, 26(1): 7-10
Abstract:
The secondary metabolites of fungus ZSUH 36 were first isolated from the mangrove plant sample.Five secondary metabolites were isolated from the mycelium of this strain by means of column chromatography.Their structures were identified by comprehensive spectroscopic methods including IR,MS,NMR.To the best of our knowledge,compound 1 and compound 2 were both isolated from marine fungi for the first time.In the preliminary bioassay,compound 5 shows moderate inhibitory activity on the hepG2 cell line with an IC50 value of 3.0×10-5 g/mL.
The secondary metabolites of fungus ZSUH 36 were first isolated from the mangrove plant sample.Five secondary metabolites were isolated from the mycelium of this strain by means of column chromatography.Their structures were identified by comprehensive spectroscopic methods including IR,MS,NMR.To the best of our knowledge,compound 1 and compound 2 were both isolated from marine fungi for the first time.In the preliminary bioassay,compound 5 shows moderate inhibitory activity on the hepG2 cell line with an IC50 value of 3.0×10-5 g/mL.
2009, 26(1): 11-14
Abstract:
Perovskite-type oxides La1-xSrxMnO3(x=0,0.1,0.2,0.3,0.4,0.5,0.7 and 0.9) were synthesized by the citric method and used for total catalytic combustion of benzene.They were characterized by means of XRD,O2-TPD and H2-TPR,and it was found that oxygen vacancy was not present in La1-xSrxMnO3 with Sr doping,and the valence of Mn was increased with Sr doping.The redox properties of La1-xSrxMnO3 have been improved by Sr doping,but the redox of Mn4+ would be limited by the further increase of Sr content.The La1-xSrxMnO3 oxides showed higher activity in total combustion of benzene,and La1-xSrxMnO3 oxides exhibited the best properties when x=0.2~0.3.
Perovskite-type oxides La1-xSrxMnO3(x=0,0.1,0.2,0.3,0.4,0.5,0.7 and 0.9) were synthesized by the citric method and used for total catalytic combustion of benzene.They were characterized by means of XRD,O2-TPD and H2-TPR,and it was found that oxygen vacancy was not present in La1-xSrxMnO3 with Sr doping,and the valence of Mn was increased with Sr doping.The redox properties of La1-xSrxMnO3 have been improved by Sr doping,but the redox of Mn4+ would be limited by the further increase of Sr content.The La1-xSrxMnO3 oxides showed higher activity in total combustion of benzene,and La1-xSrxMnO3 oxides exhibited the best properties when x=0.2~0.3.
2009, 26(1): 15-20
Abstract:
The stabilities of polyoxometalate(POM)/mesoporous molecular sieve hybrid material SiW11/SBA-15,including thermal stability,hydrothermal stability and ability against solvent-leaching,were investigated by means of TG-DTA,XRD,FT-IR,N2 adsorption-desorption and ICP-AES.It was found that POM species,SiW11O39[O(SiO-)2]6-,in the hybrid materials was less stable than the corresponding pure compound and was decomposed into SiO2 and WO3 under the calcination at 500 ℃.Therefore,the calcination should be avoided in the removal of the template.The POM species in the hybrid materials possesses higher stability against solvent-leaching;the percentage of the species lost in water at room temperature is much less than that of POM species in the impregnated samples,exhibiting high immobility of chemically bound species on the support.However,a considerable amount of POM was leached by hot water due to the hydrolysis of Si—O—W bonds.After hydrothermal treatment,the hexagonal mesostructure of the hybrid materials was retained,accompanied by the shrinkage in pore walls and increases in pore size and pore volume.The remains of mesostructure after removing POM species revealed that POM species mostly located on the surface of pore walls rather than within the SiO2 network in walls.
The stabilities of polyoxometalate(POM)/mesoporous molecular sieve hybrid material SiW11/SBA-15,including thermal stability,hydrothermal stability and ability against solvent-leaching,were investigated by means of TG-DTA,XRD,FT-IR,N2 adsorption-desorption and ICP-AES.It was found that POM species,SiW11O39[O(SiO-)2]6-,in the hybrid materials was less stable than the corresponding pure compound and was decomposed into SiO2 and WO3 under the calcination at 500 ℃.Therefore,the calcination should be avoided in the removal of the template.The POM species in the hybrid materials possesses higher stability against solvent-leaching;the percentage of the species lost in water at room temperature is much less than that of POM species in the impregnated samples,exhibiting high immobility of chemically bound species on the support.However,a considerable amount of POM was leached by hot water due to the hydrolysis of Si—O—W bonds.After hydrothermal treatment,the hexagonal mesostructure of the hybrid materials was retained,accompanied by the shrinkage in pore walls and increases in pore size and pore volume.The remains of mesostructure after removing POM species revealed that POM species mostly located on the surface of pore walls rather than within the SiO2 network in walls.
2009, 26(1): 21-26
Abstract:
A series of Ephedrine-imprinted polymers were prepared with methacrylic acid(MAA) or 2-vinylpyridine(2-Vpy) as functional monomer and chloroform,acetonitrile or methanol as porogen.The equilibrium binding experiments results show that the imprinted polymer P1,prepared with MAA as the functional monomer,chloroform as the porogen,obviously exhibited a higher selectivity for Ephedrine.The specific binding capacity(ΔCP) and imprinting factor(IF) of P1 were 91.98 μmol/g and 4.42,respectively.The polymer prepared with methanol as the porogen showed the highest binding capacity for ephedrine.However,its higher binding capacity mainly originated from the unspecific binding.The recognition ability of the molecularly imprinted polymer was effectively influenced by the molar ratio of the template to functional monomer.The results of UV and 1H NMR experiments suggest that a template-monomer complex was formed based on hydrogen bonding and ionic interactions in the pre-polymeric mixture,and the molar ratio of template to monomer in the complex was 1:2.The equilibrium constants of the reactions for producing the template-monomer complexes in chloroform,acetonitrile and methanol were calculated to be 48 450.8,45 813.3 and 23 418.2(mol/L)-2,respectively.
A series of Ephedrine-imprinted polymers were prepared with methacrylic acid(MAA) or 2-vinylpyridine(2-Vpy) as functional monomer and chloroform,acetonitrile or methanol as porogen.The equilibrium binding experiments results show that the imprinted polymer P1,prepared with MAA as the functional monomer,chloroform as the porogen,obviously exhibited a higher selectivity for Ephedrine.The specific binding capacity(ΔCP) and imprinting factor(IF) of P1 were 91.98 μmol/g and 4.42,respectively.The polymer prepared with methanol as the porogen showed the highest binding capacity for ephedrine.However,its higher binding capacity mainly originated from the unspecific binding.The recognition ability of the molecularly imprinted polymer was effectively influenced by the molar ratio of the template to functional monomer.The results of UV and 1H NMR experiments suggest that a template-monomer complex was formed based on hydrogen bonding and ionic interactions in the pre-polymeric mixture,and the molar ratio of template to monomer in the complex was 1:2.The equilibrium constants of the reactions for producing the template-monomer complexes in chloroform,acetonitrile and methanol were calculated to be 48 450.8,45 813.3 and 23 418.2(mol/L)-2,respectively.
2009, 26(1): 27-31
Abstract:
Six water samples contaminated by bacteria were prepared.The bactericidal capabilities of polydimethyldiallylammonium chloride(PDM) with series intrinsic viscosity were studied under the effect of kind,content of substrate and bacterial content.The results showed that the bactericidal rates of PDM against the 4 samples of slightly polluted water(bacteria content 1×104～1×105 cells/mL) containing 0.1% or 10% organic,inorganic substrates and the 2 samples of heavily polluted water(bacteria content 1×106～1×107 cells/mL) containing 10% organic,inorganic substrates increased firstly with the increase of dosage.The bactericidal rates approached to or exceeded 99% when dosage reached 4,0.03,11,0.10,14,2.8 mg/L respectively.Thus,the content of organic substrates influenced the bactericidal performance of PDM obviously.A low content of inorganic substrates influenced the bactericidal rates of PDM least.It could be estimated that the actual dosages of PDM(η:0.48,1.53,2.52,3.99 dL/g) were 0.029,0.028,0.027,0.026 mg/L and 2.73,2.35,2.33,2.31 mg/L respectively against slightly and heavily polluted water samples without substrates when the bactericidal rates reached 99%.The higher the intrinsic viscosity of PDM,the better the bactericidal performance.
Six water samples contaminated by bacteria were prepared.The bactericidal capabilities of polydimethyldiallylammonium chloride(PDM) with series intrinsic viscosity were studied under the effect of kind,content of substrate and bacterial content.The results showed that the bactericidal rates of PDM against the 4 samples of slightly polluted water(bacteria content 1×104～1×105 cells/mL) containing 0.1% or 10% organic,inorganic substrates and the 2 samples of heavily polluted water(bacteria content 1×106～1×107 cells/mL) containing 10% organic,inorganic substrates increased firstly with the increase of dosage.The bactericidal rates approached to or exceeded 99% when dosage reached 4,0.03,11,0.10,14,2.8 mg/L respectively.Thus,the content of organic substrates influenced the bactericidal performance of PDM obviously.A low content of inorganic substrates influenced the bactericidal rates of PDM least.It could be estimated that the actual dosages of PDM(η:0.48,1.53,2.52,3.99 dL/g) were 0.029,0.028,0.027,0.026 mg/L and 2.73,2.35,2.33,2.31 mg/L respectively against slightly and heavily polluted water samples without substrates when the bactericidal rates reached 99%.The higher the intrinsic viscosity of PDM,the better the bactericidal performance.
2009, 26(1): 32-36
Abstract:
The Keggin inorganic-organic hybrid molybdovanadophosphoricimidazo-lium([Bmim]5PMo10V2O40) was prepared and characterized by elemental analysis,ICP-AES,IR,TG and DTA.Electrochemical behavior of pyrocatechol and H2O2 was investigated at the carbon paste electrode(CPE) modified by [Bmim]5PMo10V2O40(B-PMo10V2O40-CPE) in 0.5 mol/L H2SO4 aqueous solution.Compared with the response of pyrocatechol and H2O2 at the bare CPE,the ΔEP of the redox potential of pyrocatechol at the B-PMo10V2O40-CPE decreased by 108 mV,and the redox current increased remarkably.The irreversible reduction peaks of H2O25PMo10V2O40 retained electrocatalytic activities toward the redox of pyrocatechol and the reduction of hydrogen peroxide,and the fabricated modified electrode showed remarkable stability,excellent repeatability and is surface-renewalbe.
The Keggin inorganic-organic hybrid molybdovanadophosphoricimidazo-lium([Bmim]5PMo10V2O40) was prepared and characterized by elemental analysis,ICP-AES,IR,TG and DTA.Electrochemical behavior of pyrocatechol and H2O2 was investigated at the carbon paste electrode(CPE) modified by [Bmim]5PMo10V2O40(B-PMo10V2O40-CPE) in 0.5 mol/L H2SO4 aqueous solution.Compared with the response of pyrocatechol and H2O2 at the bare CPE,the ΔEP of the redox potential of pyrocatechol at the B-PMo10V2O40-CPE decreased by 108 mV,and the redox current increased remarkably.The irreversible reduction peaks of H2O25PMo10V2O40 retained electrocatalytic activities toward the redox of pyrocatechol and the reduction of hydrogen peroxide,and the fabricated modified electrode showed remarkable stability,excellent repeatability and is surface-renewalbe.
2009, 26(1): 37-41
Abstract:
The adsorption performance of plant oil for phenol was studied by ultraviolet spectrophotometry.The effects of time,temperature,the mass concentration of phenol,the dosage of plant oil,and pH on the adsorption capacity of plant oil for phenol were investigated.The adsorption kinetics and thermodynamics of phenol onto plant oil were also discussed.The results show that the four influencing factors were in the following order of significance: the mass concentration of phenol> the dosage of plant oil> temperature> pH.The optimum adsorption conditions were the 3 g of plant oil,temperature of 20 ℃,pH of 6.2,and the mass concentration of phenol 20 mg/L.The adsorption capacity of plant oil for phenol was 0.07 mg/g.The adsorption of phenol onto plant oil obeyed Freundlich equation.
The adsorption performance of plant oil for phenol was studied by ultraviolet spectrophotometry.The effects of time,temperature,the mass concentration of phenol,the dosage of plant oil,and pH on the adsorption capacity of plant oil for phenol were investigated.The adsorption kinetics and thermodynamics of phenol onto plant oil were also discussed.The results show that the four influencing factors were in the following order of significance: the mass concentration of phenol> the dosage of plant oil> temperature> pH.The optimum adsorption conditions were the 3 g of plant oil,temperature of 20 ℃,pH of 6.2,and the mass concentration of phenol 20 mg/L.The adsorption capacity of plant oil for phenol was 0.07 mg/g.The adsorption of phenol onto plant oil obeyed Freundlich equation.
2009, 26(1): 42-46
Abstract:
Novel chiral triethoxysilane derivatives of(S)-1,1'-bi-2-naphthol(BINOL) substituted at 3 and 3,3' positions of binaphthyl backbone were synthesized conveniently from 2,2'-bis(methoxymethy)-1,1'-binaphthol through three steps,i.e.,carbonylation,reduction and Williamson reaction with 3-chloropropyltriethoxysilane using sodium hydride as a deprotonation reagent.Other chiral triethoxysilane derivatives of(S)-BINOL substituted at 6 and 6,6' positions of binaphthyl backbone were prepared through four steps,including bromization at 6 and 6,6' positions of binaphthyl backbone in addition to the three steps mentioned above.The yields of the four compounds are 84%,62%,82% and 67% respectively.The obtained compounds are stable at room temperature and can be purified by column chromatography.The structures of the final products were characterized by 1H NMR,13C NMR,29Si NMR,IR,ESI-MS and elemental analysis.The silicon atom was confirmed to exist as triethoxysilane in the derivatives by 29Si NMR.
Novel chiral triethoxysilane derivatives of(S)-1,1'-bi-2-naphthol(BINOL) substituted at 3 and 3,3' positions of binaphthyl backbone were synthesized conveniently from 2,2'-bis(methoxymethy)-1,1'-binaphthol through three steps,i.e.,carbonylation,reduction and Williamson reaction with 3-chloropropyltriethoxysilane using sodium hydride as a deprotonation reagent.Other chiral triethoxysilane derivatives of(S)-BINOL substituted at 6 and 6,6' positions of binaphthyl backbone were prepared through four steps,including bromization at 6 and 6,6' positions of binaphthyl backbone in addition to the three steps mentioned above.The yields of the four compounds are 84%,62%,82% and 67% respectively.The obtained compounds are stable at room temperature and can be purified by column chromatography.The structures of the final products were characterized by 1H NMR,13C NMR,29Si NMR,IR,ESI-MS and elemental analysis.The silicon atom was confirmed to exist as triethoxysilane in the derivatives by 29Si NMR.
2009, 26(1): 47-50
Abstract:
The palladium acetate-catalyzed synthesis of chalcones in water in the presence of 1-butyl-3-methylimidazolium hexafluorophosphate([bmim][ PF6]) is described.The Pd(OAc)2-[bmim][PF6]-H2O catalytic system can be recovered and reused six times with high efficiency.Compared with previous methods in organic systems,aqueous medium is active,air stable,recyclable,and involving no expensive and enviro-nmentally unfavorable phosphine ligand.
The palladium acetate-catalyzed synthesis of chalcones in water in the presence of 1-butyl-3-methylimidazolium hexafluorophosphate([bmim][ PF6]) is described.The Pd(OAc)2-[bmim][PF6]-H2O catalytic system can be recovered and reused six times with high efficiency.Compared with previous methods in organic systems,aqueous medium is active,air stable,recyclable,and involving no expensive and enviro-nmentally unfavorable phosphine ligand.
2009, 26(1): 51-54
Abstract:
A novel hydrazine-containing diamine 3,3'-bis(N-aminophthalimide) thioether was synthesized.Its structure was determined by means of 1H NMR and IR.Two polyimides were prepared with the diamine and dianhydrides 4,4'-HQDPA or BPADA via conventional one-step method in p-chlorophenol.These polymers show very good solubility in polar aprotic solvents and phenols at room temperature.The glass-transition temperatures of the polymers are 324 ℃ and 280 ℃,and the temperatures at which the mass loss is 5% are 486 ℃ and 466 ℃.
A novel hydrazine-containing diamine 3,3'-bis(N-aminophthalimide) thioether was synthesized.Its structure was determined by means of 1H NMR and IR.Two polyimides were prepared with the diamine and dianhydrides 4,4'-HQDPA or BPADA via conventional one-step method in p-chlorophenol.These polymers show very good solubility in polar aprotic solvents and phenols at room temperature.The glass-transition temperatures of the polymers are 324 ℃ and 280 ℃,and the temperatures at which the mass loss is 5% are 486 ℃ and 466 ℃.
2009, 26(1): 55-58
Abstract:
ZrO2/PVP hybrid fibers were successfully prepared from the blend of spinnable zirconium sol and 10%PVP solution by dry spinning.FT-IR,TG,SEM and XRD were applied to study the chemical structure and microstructure of the hybrid fibers as well as influence of hybrid degree on the sintered ZrO2 fibers.The results show that ZrO2/PVP hybrid fibers with a diameter of 10~25 μm can be more than tens meters in length.The hybrid between PVP and zirconium sol is formed by Zr-O coordinate linkage.The fibers retained their original shape after sintering,but became finer.The sintered fibers contracted more strongly,even cracked when the ZrO2 content in the hybrid fibers decreased.The lower the ZrO2 content,the smaller the crystal grains of ZrO2 in the sintered fibers.At the same ZrO2 content,the crystal grains of ZrO2 increased with the sintering temperature increase.
ZrO2/PVP hybrid fibers were successfully prepared from the blend of spinnable zirconium sol and 10%PVP solution by dry spinning.FT-IR,TG,SEM and XRD were applied to study the chemical structure and microstructure of the hybrid fibers as well as influence of hybrid degree on the sintered ZrO2 fibers.The results show that ZrO2/PVP hybrid fibers with a diameter of 10~25 μm can be more than tens meters in length.The hybrid between PVP and zirconium sol is formed by Zr-O coordinate linkage.The fibers retained their original shape after sintering,but became finer.The sintered fibers contracted more strongly,even cracked when the ZrO2 content in the hybrid fibers decreased.The lower the ZrO2 content,the smaller the crystal grains of ZrO2 in the sintered fibers.At the same ZrO2 content,the crystal grains of ZrO2 increased with the sintering temperature increase.
2009, 26(1): 59-62
Abstract:
A series of novel 1-(2-trifluoromethylbenzimidazol-1-acetyl)-4-aroylthios-emicarbazides(2a~2k) was synthesized by the reaction of 1-hydrazinocarbonylmethyl-2-trifluoromethylbenzimidazole with each of aroylisothiocyanates(1a~1k) under microwave irradiation and classical heating conditions.Compared to classical heating method,microwave irradiation has many advantages in the organic synthesis process,such as simple operation,short reaction time,high yields,less side reactions and easy purification of products.The structures of these compounds were confirmed by elemental analysis,IR,and 1H NMR.The preliminary biological activities of the target compounds were tested,and the result showed that only compound 2a had low anti-HIV-1 reverse transcriptase activity.
A series of novel 1-(2-trifluoromethylbenzimidazol-1-acetyl)-4-aroylthios-emicarbazides(2a~2k) was synthesized by the reaction of 1-hydrazinocarbonylmethyl-2-trifluoromethylbenzimidazole with each of aroylisothiocyanates(1a~1k) under microwave irradiation and classical heating conditions.Compared to classical heating method,microwave irradiation has many advantages in the organic synthesis process,such as simple operation,short reaction time,high yields,less side reactions and easy purification of products.The structures of these compounds were confirmed by elemental analysis,IR,and 1H NMR.The preliminary biological activities of the target compounds were tested,and the result showed that only compound 2a had low anti-HIV-1 reverse transcriptase activity.
2009, 26(1): 63-66
Abstract:
To improve the water solubility of fused heterocyclis so as to find a novel structural lead compound from them for the development of potential antibacterial agents,the intermediates of 6-(5-chloro-3-methyl-1-substituted phenyl-1H-pyrazol-4-yl)-3-pyrid-3-yl-s-triazolothiadia-zoles(3a~3c) were synthesized via cyclocondensation of 4-amino-3-pyrid-3-yl-5-mercapto-s-triazole(2) with chloro-pyrazole carboxylic acids(1a~1c) catalyzed with a phase transfer catalyst TBAB and an acylating catalyst DMAP in the presence of POCl3 in high yields,respectively.The compounds 3a~3c were subjected to nucleophilic substitution of the chlorine at the pyrazole ring with substituted piperazine under the catalysis of PEG-600 to give the corresponding free bases 4a~4o successfully,which were subsequently treated with hydrochloride to afford corresponding chlorides of 4a~4o.The structures of the title compounds were characterized by elemental analysis and spectral data,and the in vitro inhibitory activities of the title compounds against three microorgranisms,S.aureus,E.coli,and P.aeruginosa,were evaluated via the respective MICs values by means of 2-fold agar dilution assay.The results showed that the introduction of a polar piperazine group around the fused heterocyclic core of s-tria-zolothiadiazole could result in a significant enhancement of bioactivity of the corresponding parent compounds.
To improve the water solubility of fused heterocyclis so as to find a novel structural lead compound from them for the development of potential antibacterial agents,the intermediates of 6-(5-chloro-3-methyl-1-substituted phenyl-1H-pyrazol-4-yl)-3-pyrid-3-yl-s-triazolothiadia-zoles(3a~3c) were synthesized via cyclocondensation of 4-amino-3-pyrid-3-yl-5-mercapto-s-triazole(2) with chloro-pyrazole carboxylic acids(1a~1c) catalyzed with a phase transfer catalyst TBAB and an acylating catalyst DMAP in the presence of POCl3 in high yields,respectively.The compounds 3a~3c were subjected to nucleophilic substitution of the chlorine at the pyrazole ring with substituted piperazine under the catalysis of PEG-600 to give the corresponding free bases 4a~4o successfully,which were subsequently treated with hydrochloride to afford corresponding chlorides of 4a~4o.The structures of the title compounds were characterized by elemental analysis and spectral data,and the in vitro inhibitory activities of the title compounds against three microorgranisms,S.aureus,E.coli,and P.aeruginosa,were evaluated via the respective MICs values by means of 2-fold agar dilution assay.The results showed that the introduction of a polar piperazine group around the fused heterocyclic core of s-tria-zolothiadiazole could result in a significant enhancement of bioactivity of the corresponding parent compounds.
2009, 26(1): 67-71
Abstract:
Three heteropolyoxometalates containing lithium were prepared by means of direct method and degradation for the first time.The chemical formulas were confirmed as Kn[XLi(OH2)W11O39]·xH2O(X=Si,P,B) by ICP and TG and their structures were characterized by IR,UV,XRD,XPS and 183W NMR.The results show that the new materials are all of Keggin-type structure,in which one W atom has been substituted by one Li atom.The results of DTA indicate that the new materials have good thermostability.The redox cesses are irreversible.The determination results of conductivity show they all have conductivity and the conductivities are 2.4×10-6 S/cm for K7[SiLi(OH2)W11O39]·xH2O,3.8×10-6 S/cm for K6[PLi(OH2)W11O39]·xH2O,7.3×10-7 S/cm for K8[BLi(OH2)W11O39]·xH2O,respectively.
Three heteropolyoxometalates containing lithium were prepared by means of direct method and degradation for the first time.The chemical formulas were confirmed as Kn[XLi(OH2)W11O39]·xH2O(X=Si,P,B) by ICP and TG and their structures were characterized by IR,UV,XRD,XPS and 183W NMR.The results show that the new materials are all of Keggin-type structure,in which one W atom has been substituted by one Li atom.The results of DTA indicate that the new materials have good thermostability.The redox cesses are irreversible.The determination results of conductivity show they all have conductivity and the conductivities are 2.4×10-6 S/cm for K7[SiLi(OH2)W11O39]·xH2O,3.8×10-6 S/cm for K6[PLi(OH2)W11O39]·xH2O,7.3×10-7 S/cm for K8[BLi(OH2)W11O39]·xH2O,respectively.
2009, 26(1): 72-77
Abstract:
Silica gel particles on which quaternized polyethyleneimine was grafted were used in the removal of chromate anions.Polyethyleneimine(PEI) was first grafted on the surface of the silica gel particles via the coupling of γ-chloropropyl trimethoxy silane,resulting in grafting PEI/SiO2 particles.Then,the grafted PEI was quaternized via two polymeric reactions,tertiary amine reaction and quaternization,and the functional particles QPEI/SiO2,on which quaternized PEI was grafted,was obtained.The infrared spectrum of QPEI/SiO2 was obtained and its chemical structure was characterized.The Zeta potential of the QPEI/SiO2 particles was also determined.The adsorption property of QPEI/SiO2 for chromate anions was studied with the static method.The experimental results show that the QPEI/SiO2 particles have a very strong adsorption ability by strong electrostatic interaction,and the saturated adsorption amount can reach 0.14 g/g.The isotherm adsorption obeys Langmuir equation.The major factor which affects the adsorption property of QPEI/SiO2 for chromate anions is the quaternization degree of QPEI/SiO2,and the QPEI/SiO2 particles with higher quaternization degree have a higher adsorption capacity.The pH of the medium has little effect on the adsorption property of QPEI/SiO2.
Silica gel particles on which quaternized polyethyleneimine was grafted were used in the removal of chromate anions.Polyethyleneimine(PEI) was first grafted on the surface of the silica gel particles via the coupling of γ-chloropropyl trimethoxy silane,resulting in grafting PEI/SiO2 particles.Then,the grafted PEI was quaternized via two polymeric reactions,tertiary amine reaction and quaternization,and the functional particles QPEI/SiO2,on which quaternized PEI was grafted,was obtained.The infrared spectrum of QPEI/SiO2 was obtained and its chemical structure was characterized.The Zeta potential of the QPEI/SiO2 particles was also determined.The adsorption property of QPEI/SiO2 for chromate anions was studied with the static method.The experimental results show that the QPEI/SiO2 particles have a very strong adsorption ability by strong electrostatic interaction,and the saturated adsorption amount can reach 0.14 g/g.The isotherm adsorption obeys Langmuir equation.The major factor which affects the adsorption property of QPEI/SiO2 for chromate anions is the quaternization degree of QPEI/SiO2,and the QPEI/SiO2 particles with higher quaternization degree have a higher adsorption capacity.The pH of the medium has little effect on the adsorption property of QPEI/SiO2.
2009, 26(1): 78-81
Abstract:
A novel electrolyte of phosphotungstic acid(PWA) doped with P2O5 was prepared.The effects of P2O5 concentration and relative humidity on the conductivity of the electrolyte were investigated by the impedance at room temperature.The results indicate that the conductivity of 7% P2O5/PWA electrolyte is 0.045 S/cm at room temperature.The conductivity of the electrolyte changes slightly at a relative humidity range of 20%~70%.The mass loss of P2O5/PWA electrolyte heated to 40 ℃ is less than 2%,which indicated that if has a good ability to retain water.
A novel electrolyte of phosphotungstic acid(PWA) doped with P2O5 was prepared.The effects of P2O5 concentration and relative humidity on the conductivity of the electrolyte were investigated by the impedance at room temperature.The results indicate that the conductivity of 7% P2O5/PWA electrolyte is 0.045 S/cm at room temperature.The conductivity of the electrolyte changes slightly at a relative humidity range of 20%~70%.The mass loss of P2O5/PWA electrolyte heated to 40 ℃ is less than 2%,which indicated that if has a good ability to retain water.
2009, 26(1): 82-85
Abstract:
A low temperature method was used to obtain bio-oil from fir sawdust by means of microwave pyrolysis.Fir sawdust was mixed with a microwave absorption medium(ionic liquid) in the pyrolysis process and super-critical CO2 extraction was used to separate the product.Effects of reaction temperature,ratios of the ionic liquid to fir,and reaction time on the yield of bio-oil were investigated,and the results show that the optimal processing conditions were that ratio of ionic liquid to fir sawdust was 4:3,reaction temperature was 200 ℃,and reaction time was 30 minutes.Yield of bio-oil can reach 21.22%.Bio-oil obtained was analyzed by GC-MS,FTIR,and TG-DTA,and the results revealed that product consisted of aromatic hydrocarbons,such as phenols,esters and acids.TG-DTA showed that the product was a fuel with good combustibility.
A low temperature method was used to obtain bio-oil from fir sawdust by means of microwave pyrolysis.Fir sawdust was mixed with a microwave absorption medium(ionic liquid) in the pyrolysis process and super-critical CO2 extraction was used to separate the product.Effects of reaction temperature,ratios of the ionic liquid to fir,and reaction time on the yield of bio-oil were investigated,and the results show that the optimal processing conditions were that ratio of ionic liquid to fir sawdust was 4:3,reaction temperature was 200 ℃,and reaction time was 30 minutes.Yield of bio-oil can reach 21.22%.Bio-oil obtained was analyzed by GC-MS,FTIR,and TG-DTA,and the results revealed that product consisted of aromatic hydrocarbons,such as phenols,esters and acids.TG-DTA showed that the product was a fuel with good combustibility.
2009, 26(1): 86-89
Abstract:
Stable fluoroacrylate copolymer P(FA-BA-MMA) was successfully synthesized by miniemulsion polymerization under microwave irradiation.Conversion of the monomers was determined by gravimetry.The water resistance of the latex films was investigated and the stability of the miniemulsion was observed.The surface properties of the copolymer films were investigated by contact angle measurement.The results show that the miniemulsion copolymerization under microwave irradiation had higher reaction rate and higher conversion than traditional heating,and the centrifugal stability was better.The monomerconversion under microwave irradiation was 80% at 10 min.The water absorption ratio and surface free energy of the fluorinated acrylate films both decreased evidently compared with that of the acrylate copolymer films without fluorine.The water absorption ratio and the surface energy could reach 1.43% and 14.85 mJ/m2 respectively when the amount of FA used in the copolymerization was 25%.
Stable fluoroacrylate copolymer P(FA-BA-MMA) was successfully synthesized by miniemulsion polymerization under microwave irradiation.Conversion of the monomers was determined by gravimetry.The water resistance of the latex films was investigated and the stability of the miniemulsion was observed.The surface properties of the copolymer films were investigated by contact angle measurement.The results show that the miniemulsion copolymerization under microwave irradiation had higher reaction rate and higher conversion than traditional heating,and the centrifugal stability was better.The monomerconversion under microwave irradiation was 80% at 10 min.The water absorption ratio and surface free energy of the fluorinated acrylate films both decreased evidently compared with that of the acrylate copolymer films without fluorine.The water absorption ratio and the surface energy could reach 1.43% and 14.85 mJ/m2 respectively when the amount of FA used in the copolymerization was 25%.
2009, 26(1): 90-93
Abstract:
Crystalline ZnO nanorods were prepared by means of a simple one-step alcohol thermal approach with oleic acid(OA) as a stabilizing agent under atmospheric pressure.The OA-stabilized ZnO nanorods were characterized by XRD,SEM,TEM,HRTEM and FT-IR.PL spectrum of the product after annealing was studied,and the growth mechanism of ZnO nanorods was also discussed.The results showed that the nanorods grow along the direction with a diameter of 10~15 nm and a length of 150~200 nm,and the binding of OA with ZnO nanorods was confirmed by FTIR.The obtained ZnO nanorods exhibited good near-UV emission properties.With the increase of the annealing temperature,the intensity of the deep-level emission decreased and then increased.
Crystalline ZnO nanorods were prepared by means of a simple one-step alcohol thermal approach with oleic acid(OA) as a stabilizing agent under atmospheric pressure.The OA-stabilized ZnO nanorods were characterized by XRD,SEM,TEM,HRTEM and FT-IR.PL spectrum of the product after annealing was studied,and the growth mechanism of ZnO nanorods was also discussed.The results showed that the nanorods grow along the direction with a diameter of 10~15 nm and a length of 150~200 nm,and the binding of OA with ZnO nanorods was confirmed by FTIR.The obtained ZnO nanorods exhibited good near-UV emission properties.With the increase of the annealing temperature,the intensity of the deep-level emission decreased and then increased.
2009, 26(1): 94-99
Abstract:
A new method for the determination of ultra trace amounts of scandium is described.A multi-walled carbon nanotube modified carbon paste electrode was prepared and the adsorption voltammetric behavior of scandium-alizarin red S(ARS) complex at the modified electrode was investigated.By use of the second derivative linear sweep technique,it was found that in 0.32 mol/L acetic acid and 0.064 mol/L potassium biphthalate buffer solution(pH=4.0),the complex could be adsorbed on the surface of the electrode after accumulating at 100 mV for 90 s,yielding one sensitive stripping peak at-518 mV(vs.SCE) when scanning linearly from 0 mV to-1 000 mV at a scan rate of 200 mV/s,corresponding to the reduction of ARS in the complex.The peak current of the complex was linearly proportional to Sc(Ⅲ) concentration in a range of 4.0×10-11～6.0×10-7 mol/L and the detection limit(S/N=3) was 2.0×10-11 mol/L for 3 min accumulation.The developed method was applied to the determination of trace scandium in the ore samples and the results were satisfactory.
A new method for the determination of ultra trace amounts of scandium is described.A multi-walled carbon nanotube modified carbon paste electrode was prepared and the adsorption voltammetric behavior of scandium-alizarin red S(ARS) complex at the modified electrode was investigated.By use of the second derivative linear sweep technique,it was found that in 0.32 mol/L acetic acid and 0.064 mol/L potassium biphthalate buffer solution(pH=4.0),the complex could be adsorbed on the surface of the electrode after accumulating at 100 mV for 90 s,yielding one sensitive stripping peak at-518 mV(vs.SCE) when scanning linearly from 0 mV to-1 000 mV at a scan rate of 200 mV/s,corresponding to the reduction of ARS in the complex.The peak current of the complex was linearly proportional to Sc(Ⅲ) concentration in a range of 4.0×10-11～6.0×10-7 mol/L and the detection limit(S/N=3) was 2.0×10-11 mol/L for 3 min accumulation.The developed method was applied to the determination of trace scandium in the ore samples and the results were satisfactory.
2009, 26(1): 100-103
Abstract:
A series of 1-substituent-6-oxo-benzopyridazinones-3-(tetra-O-acetyl-β-D-glucopyranoside) with dextran configuration was synthesized with 1-butyl methylimidazole-4-fluoborate as the reaction media and promoter at room temperature.The products with optical rotation of(+)24.6,(+)11.0,(+)13.6 and(+)20.3 are all dextran.The article studied the influences of reaction time,molar ratio,various ionic liquids and reuse of ionic liquid on the reaction.The structures of the synthesized glycosides were characte-rized by 1H NMR and IR.The method has the advantages of mild condition,few side effects,high yield,environmental benignity,and the ionic liquid can be used again.
A series of 1-substituent-6-oxo-benzopyridazinones-3-(tetra-O-acetyl-β-D-glucopyranoside) with dextran configuration was synthesized with 1-butyl methylimidazole-4-fluoborate as the reaction media and promoter at room temperature.The products with optical rotation of(+)24.6,(+)11.0,(+)13.6 and(+)20.3 are all dextran.The article studied the influences of reaction time,molar ratio,various ionic liquids and reuse of ionic liquid on the reaction.The structures of the synthesized glycosides were characte-rized by 1H NMR and IR.The method has the advantages of mild condition,few side effects,high yield,environmental benignity,and the ionic liquid can be used again.
2009, 26(1): 104-107
Abstract:
The electroreduction behavior of antiarrhythmic drug propafenone at Hg electrode was studied by means of linear sweep polarography,and a new determination method of propafenone in factual samples was developed.In solution with pH11.6,only one reduction peak was observed in the linear sweep polarogram and the mechanism of the peak was studied.In the solution with pH11.6,two reduction waves(P1,P2) can be observed in the polarogram.P1 was proved to be a catalytic hydrogen wave and P2 was attributed to the reduction of propafenone itself.In a Britton-Robinson buffer(pH=12.3),a linear relationship can be established between the second order polarographic wave current of P1 and the concentration of propafenone in a range of 9.6×10-8 to 4.0×10-6 mol/L with a detection limit of 5×10-8 mol/L.The RSD of 6 repeated measurements of 1.0×10-6 mol/L propafenone was 1.2%.The second order polarography was utilized to determine the content of propafenone in tablets and spiked serum.The determination results of propafenone in tablets by the second order derivative polarography were in agreement with the results obtained by UV spectrophotometry,and the recovery of propafenone in spiked serum was between in 98.6% to 102%.
The electroreduction behavior of antiarrhythmic drug propafenone at Hg electrode was studied by means of linear sweep polarography,and a new determination method of propafenone in factual samples was developed.In solution with pH11.6,only one reduction peak was observed in the linear sweep polarogram and the mechanism of the peak was studied.In the solution with pH11.6,two reduction waves(P1,P2) can be observed in the polarogram.P1 was proved to be a catalytic hydrogen wave and P2 was attributed to the reduction of propafenone itself.In a Britton-Robinson buffer(pH=12.3),a linear relationship can be established between the second order polarographic wave current of P1 and the concentration of propafenone in a range of 9.6×10-8 to 4.0×10-6 mol/L with a detection limit of 5×10-8 mol/L.The RSD of 6 repeated measurements of 1.0×10-6 mol/L propafenone was 1.2%.The second order polarography was utilized to determine the content of propafenone in tablets and spiked serum.The determination results of propafenone in tablets by the second order derivative polarography were in agreement with the results obtained by UV spectrophotometry,and the recovery of propafenone in spiked serum was between in 98.6% to 102%.
2009, 26(1): 108-111
Abstract:
An organic fluorine modified polystyrene-acrylate emulsion was synthesized by a semi-continuous process with fatty alcohol poly(oxyethylene ether)/sodium dodecyl sulfate/Non-ionic fluorine containing surfactant(OP-10/SDS/DF-10) as an emulsifier system.The structure and latex particles of the copolymers were characterized by IR and TEM.The influence factors including the content of fluorine-containing methyl acrylate and fluorocarbon surfactants on the emulsion were investigated.The effects of the factors on the rate of monomer conversion and the stability of the emulsion were also studied.It was shown that the rate of monomer conversion was 99.6% when the polymerization temperature was 75～80 ℃ and the reaction time was 4.5～5 h when the mass fraction of organic fluorine was only 0.67% and that of DF-10 was 1.35%.
An organic fluorine modified polystyrene-acrylate emulsion was synthesized by a semi-continuous process with fatty alcohol poly(oxyethylene ether)/sodium dodecyl sulfate/Non-ionic fluorine containing surfactant(OP-10/SDS/DF-10) as an emulsifier system.The structure and latex particles of the copolymers were characterized by IR and TEM.The influence factors including the content of fluorine-containing methyl acrylate and fluorocarbon surfactants on the emulsion were investigated.The effects of the factors on the rate of monomer conversion and the stability of the emulsion were also studied.It was shown that the rate of monomer conversion was 99.6% when the polymerization temperature was 75～80 ℃ and the reaction time was 4.5～5 h when the mass fraction of organic fluorine was only 0.67% and that of DF-10 was 1.35%.
2009, 26(1): 112-115
Abstract:
The microcapsules of pendimethalin were prepared with 9 different sodium lignosulphonates as dispersant by in-situ polymerization.The factors affecting the morphology and the encapsulation efficiency and the particle-size were investigated,and the stability was also determined.The results show that the viscosities of the microcapsule suspensions prepared with the four sodium lignosulphonates whose sulfonation degrees were about 0.8 were higher than 12 mPa·s,while the viscosities of the microcapsules prepared with other five dispersants whose sulfonation degrees were about 3.0 and 3.5 were lower than 10 mPa·s.The particle-size of the microcapsule prepared with the ligninsulfonate of the same degree of sulfonation decreased with the molecular mass increasing.The microcapsules prepared with sodium lignosulphonates of higher molecular mass and higher degree of sulfonation had higher stability and were suited to the requirements of microcapsules.When the molecular mass of the sodium lignosulphonate was under 5 000,the microcapsules were easy to crack.The molecular mass and degree of sulfonation had little effect on the encapsulation ratio.All the encapsulation ratios of the microcapsulates prepared with different sodium lignosulphonates were above 94%.
The microcapsules of pendimethalin were prepared with 9 different sodium lignosulphonates as dispersant by in-situ polymerization.The factors affecting the morphology and the encapsulation efficiency and the particle-size were investigated,and the stability was also determined.The results show that the viscosities of the microcapsule suspensions prepared with the four sodium lignosulphonates whose sulfonation degrees were about 0.8 were higher than 12 mPa·s,while the viscosities of the microcapsules prepared with other five dispersants whose sulfonation degrees were about 3.0 and 3.5 were lower than 10 mPa·s.The particle-size of the microcapsule prepared with the ligninsulfonate of the same degree of sulfonation decreased with the molecular mass increasing.The microcapsules prepared with sodium lignosulphonates of higher molecular mass and higher degree of sulfonation had higher stability and were suited to the requirements of microcapsules.When the molecular mass of the sodium lignosulphonate was under 5 000,the microcapsules were easy to crack.The molecular mass and degree of sulfonation had little effect on the encapsulation ratio.All the encapsulation ratios of the microcapsulates prepared with different sodium lignosulphonates were above 94%.
2009, 26(1): 116-118
Abstract:
3,4-Methylenedioxyamphetamine(MDA) and 3,4-methylenedioxymethamphetamine(MDMA) in human blood were determined by means of microwave extraction-gas chromatography(GC).The optimal conditions included the pH of blood sample 13,ethyl acetate as extraction solvent,extraction at 30 ℃ for 10 min.The average recovery of MDA or MDMA with this extraction method was 96.7% or 101.7%,and the relative standard deviation of MDA or MDMA was 4.8% or 5.3%(n=5).The limit of detection was 5×10-8 g/mL for MDA and MDMA in the blood.Using this method,MDA and MDMA need not to be derivatized and can be separated from the matrix.The results indicate that the method is rapid,accurate and sensitive,and can be used for the determination of MDA and MDMA in blood samples.
3,4-Methylenedioxyamphetamine(MDA) and 3,4-methylenedioxymethamphetamine(MDMA) in human blood were determined by means of microwave extraction-gas chromatography(GC).The optimal conditions included the pH of blood sample 13,ethyl acetate as extraction solvent,extraction at 30 ℃ for 10 min.The average recovery of MDA or MDMA with this extraction method was 96.7% or 101.7%,and the relative standard deviation of MDA or MDMA was 4.8% or 5.3%(n=5).The limit of detection was 5×10-8 g/mL for MDA and MDMA in the blood.Using this method,MDA and MDMA need not to be derivatized and can be separated from the matrix.The results indicate that the method is rapid,accurate and sensitive,and can be used for the determination of MDA and MDMA in blood samples.
2009, 26(1): 119-121
Abstract:
Sucralose was esterized regioselectively by protected amino acid using N,N'-dicyclohexylcarbo-diimide(DCC) as coupling reagent.The reaction led to the formation of an intermediate which has the ester group on C6 of the sucralose molecule.The final product was obtained by removing Fmoc in the solvent of morpholine/DMF(V/V,1:1).Fmoc protected phenylalanine and leucine were used in this paper to prepare 4 new compounds via regioselective esterification and deprotection reactions.The structures of products were characterized by 1H NMR and 13C NMR.
Sucralose was esterized regioselectively by protected amino acid using N,N'-dicyclohexylcarbo-diimide(DCC) as coupling reagent.The reaction led to the formation of an intermediate which has the ester group on C6 of the sucralose molecule.The final product was obtained by removing Fmoc in the solvent of morpholine/DMF(V/V,1:1).Fmoc protected phenylalanine and leucine were used in this paper to prepare 4 new compounds via regioselective esterification and deprotection reactions.The structures of products were characterized by 1H NMR and 13C NMR.
2009, 26(1): 122-124
Abstract:
The phase behavior of a pseudo-ternary system of chloro-octamethylcyclotetrasiloxane/CTAB/glycol/water was studied with a polarimicroscope,and the pseudo-ternary phase diagram at 80 ℃ was obtained.The microemulsion polymerization was carried out with varing ratios of components,and the nucleation mechanism was discussed according to the results of the particle size distribution analysis.The antifoam performance of the microemulsion was also investigated.Results show that the microemulsion polymerization took place in water phase.Moreover,the monomer droplets provided siloxane oligomers with end-hydroxyl,and the microemulsion exhibits a better antifoam emulsion performance than that of commercial emulsion due to the introduction of chloromethyl into the siloxane.
The phase behavior of a pseudo-ternary system of chloro-octamethylcyclotetrasiloxane/CTAB/glycol/water was studied with a polarimicroscope,and the pseudo-ternary phase diagram at 80 ℃ was obtained.The microemulsion polymerization was carried out with varing ratios of components,and the nucleation mechanism was discussed according to the results of the particle size distribution analysis.The antifoam performance of the microemulsion was also investigated.Results show that the microemulsion polymerization took place in water phase.Moreover,the monomer droplets provided siloxane oligomers with end-hydroxyl,and the microemulsion exhibits a better antifoam emulsion performance than that of commercial emulsion due to the introduction of chloromethyl into the siloxane.
