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2010 Volume 27 Issue 4
2010, 27(4): 373-379
doi: 10.3724/SP.J.1095.2010.90676
Abstract:
The recent progress in the area of core colloids modified with noble metal nanoparticles is reviewed.The researches on these composite materials are hot topic in the area of material science due to their high stability,excellently catalytic and optical properties.Hence,developing simple strategy with high throughput for the preparation of these composites is very important for their further application.
The recent progress in the area of core colloids modified with noble metal nanoparticles is reviewed.The researches on these composite materials are hot topic in the area of material science due to their high stability,excellently catalytic and optical properties.Hence,developing simple strategy with high throughput for the preparation of these composites is very important for their further application.
2010, 27(4): 380-383
doi: 10.3724/SP.J.1095.2010.90360
Abstract:
The microstructures of two samples of latex dispersion system and the influence of their blending on the crystallization behavior were investigated by means of synchrotron small-angle X-ray scattering(SAXS) technique.The experimental results confirmed that the latex dispersion at a volume fraction of 50% composed of styrene-butylacrylate copolymer did not show up crystalline structures at room temperature.By virtue of fitting the scattering intensity distribution curve,the average radius of the latex particle was 76 nm,which is smaller than the value determined by dynamic light scattering(80 nm).However,the crystalline structure can be probed in the latex dispersion of styrene-butadiene copolymer with a solid content of 50%.Each Bragg peak in the scattering profile can be assigned to one or several crystal indices by assuming diffraction from a face-centered-cubic crystalline structure with a lattice constant of 212 nm.The diffraction peaks can be detected after mixing the two latex dispersion samples,implying that the partial crystallites in the original latex solution are still stable in the blending process.
The microstructures of two samples of latex dispersion system and the influence of their blending on the crystallization behavior were investigated by means of synchrotron small-angle X-ray scattering(SAXS) technique.The experimental results confirmed that the latex dispersion at a volume fraction of 50% composed of styrene-butylacrylate copolymer did not show up crystalline structures at room temperature.By virtue of fitting the scattering intensity distribution curve,the average radius of the latex particle was 76 nm,which is smaller than the value determined by dynamic light scattering(80 nm).However,the crystalline structure can be probed in the latex dispersion of styrene-butadiene copolymer with a solid content of 50%.Each Bragg peak in the scattering profile can be assigned to one or several crystal indices by assuming diffraction from a face-centered-cubic crystalline structure with a lattice constant of 212 nm.The diffraction peaks can be detected after mixing the two latex dispersion samples,implying that the partial crystallites in the original latex solution are still stable in the blending process.
2010, 27(4): 384-389
doi: 10.3724/SP.J.1095.2010.90385
Abstract:
A series of ferrocenecarboxylic acid imprinted polymers from different functional monomers were prepared and their adsorption properties for the template were evaluated by equilibrium binding experiments.The results indicate that the imprinted polymer P1,prepared with methacrylic acid as the functional monomer, exhibited a higher selectivity for ferrocenecarboxylic acid.The specific binding capacity(△CP) and imprinting factor(IF) of P1 are 23.18 μmol/g and 2.33,respectively.The results of competitive binding experiments show that P1 can separate the template from its structural analogues.Scatchard analysis demonstrates that one equal class 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 are 1.94 mmol/L and 92.33 μmol/g,respectively.The study suggests that the carboxyl of the template is the function group responsible for the formation of complementary interacting site in the polymer P1,and the double hydrogen bonds formed between the carboxyl groups of ferrocenecarboxylic acid and methacrylic acid are the main interactions in the recognition process.
A series of ferrocenecarboxylic acid imprinted polymers from different functional monomers were prepared and their adsorption properties for the template were evaluated by equilibrium binding experiments.The results indicate that the imprinted polymer P1,prepared with methacrylic acid as the functional monomer, exhibited a higher selectivity for ferrocenecarboxylic acid.The specific binding capacity(△CP) and imprinting factor(IF) of P1 are 23.18 μmol/g and 2.33,respectively.The results of competitive binding experiments show that P1 can separate the template from its structural analogues.Scatchard analysis demonstrates that one equal class 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 are 1.94 mmol/L and 92.33 μmol/g,respectively.The study suggests that the carboxyl of the template is the function group responsible for the formation of complementary interacting site in the polymer P1,and the double hydrogen bonds formed between the carboxyl groups of ferrocenecarboxylic acid and methacrylic acid are the main interactions in the recognition process.
2010, 27(4): 390-393
doi: 10.3724/SP.J.1095.2010.90406
Abstract:
Compared to traditional acylchloride reagent,bistrichloromethylcarbonate(BTC) is an excellent acylchloride reagent.Aromatic acids and aliphatic acids react with it to afford the corresponding acylchloride compounds in high yields(99%). In addition,Yb(OTf)3 catalyzed efficiently the desired process.
Compared to traditional acylchloride reagent,bistrichloromethylcarbonate(BTC) is an excellent acylchloride reagent.Aromatic acids and aliphatic acids react with it to afford the corresponding acylchloride compounds in high yields(99%). In addition,Yb(OTf)3 catalyzed efficiently the desired process.
2010, 27(4): 394-397
doi: 10.3724/SP.J.1095.2010.90377
Abstract:
A new anthraquinone derivative,6,8-dimethoxy-1-methyl-2-(3-oxobutyl) anthrakunthone(1),together with five known compounds,7-hydroxy-3-(4-methoxyphenyl)-chromen-4-one(2),2,4-dihydroxy-6-[(1'E,3'E)-penta-1',3'-dienyl]-benzaldehyde(3),(E)-4hydroxycinnamic acid methyl ester(4),4-(4-hydroxyphenyl)-butan2-ol(5),and 4-hydroxybenzoic acid(6),were isolated from the marine mangrove endophytic fungus Fusarium sp.ZZF60 from the South China Sea.Their structures were elucidated by spectral data of IR,MS and NMR.In the preliminary bioassay,compound 1 showed cytotoxicity towards Hep2 and HepG2 with IC50 values of 16 μmol/L and 23 μmol/L,respectively.
A new anthraquinone derivative,6,8-dimethoxy-1-methyl-2-(3-oxobutyl) anthrakunthone(1),together with five known compounds,7-hydroxy-3-(4-methoxyphenyl)-chromen-4-one(2),2,4-dihydroxy-6-[(1'E,3'E)-penta-1',3'-dienyl]-benzaldehyde(3),(E)-4hydroxycinnamic acid methyl ester(4),4-(4-hydroxyphenyl)-butan2-ol(5),and 4-hydroxybenzoic acid(6),were isolated from the marine mangrove endophytic fungus Fusarium sp.ZZF60 from the South China Sea.Their structures were elucidated by spectral data of IR,MS and NMR.In the preliminary bioassay,compound 1 showed cytotoxicity towards Hep2 and HepG2 with IC50 values of 16 μmol/L and 23 μmol/L,respectively.
2010, 27(4): 398-403
doi: 10.3724/SP.J.1095.2010.90334
Abstract:
Four N,N-bis(8-flavonmethyl)geranylamine derivatives were designed and synthesized.The structures of the synthesized compounds were determined from the results of 1H NMR,MS and elemental analysis.The prelimilary cytotoxicity was evaluated on K562 and SMMC7721 cell lines by MTT assay.The results demonstrate that all the compounds possess antitumor actitity and compound 1c is the best among them with an IC50 value of 5.78 μmol/L or 3.85 μmol/L against K562 or SMMC7721 cell lines,respectively.The in vitro antitumor activities of compounds 1a and 1c against K562 were better than that of the commercial drug Melphalan.The interaction of compound 1c with herring sperm DNA was explored with ethidium bromide(EB) as a fluorescence probe.The result of the study on fluorescence quenching by DNA-EB confirms the strong interaction of compound 1c with Herring Sperm DNA.
Four N,N-bis(8-flavonmethyl)geranylamine derivatives were designed and synthesized.The structures of the synthesized compounds were determined from the results of 1H NMR,MS and elemental analysis.The prelimilary cytotoxicity was evaluated on K562 and SMMC7721 cell lines by MTT assay.The results demonstrate that all the compounds possess antitumor actitity and compound 1c is the best among them with an IC50 value of 5.78 μmol/L or 3.85 μmol/L against K562 or SMMC7721 cell lines,respectively.The in vitro antitumor activities of compounds 1a and 1c against K562 were better than that of the commercial drug Melphalan.The interaction of compound 1c with herring sperm DNA was explored with ethidium bromide(EB) as a fluorescence probe.The result of the study on fluorescence quenching by DNA-EB confirms the strong interaction of compound 1c with Herring Sperm DNA.
2010, 27(4): 404-408
doi: 10.3724/SP.J.1095.2010.90390
Abstract:
Hexaphenoxycyclotriphosphazene(HPCTP)was synthesized by the reaction of crude hexachloro-cyclotriphosphazene(HCCTP) with phenol and sodium hydroxide,with tetrabutylammonium chloride(TBAC) as phase transfer catalyst and chlorobenzene/water as solvent.Effects of reaction temperature,reaction time,solvent and molar ratio of raw matesials on the yield of HPCTP were investigated.Under the optimized reaction conditions of n(sodium hydroxide):n(phenol):n(TBAC):n(crude HCCTP)=7.5:6.3:0.15:1,reaction time of 4 h at 30℃ plus 6 h at reflux temperature,the yield was 75%.The product was characterized by FTIR,1H NMR,13C NMR,31P NMR,XRD,DSC and TGA.The product has been firstly applied in benzoxazine resin glass cloth laminate.The flammability class of the laminate was in the rank of V-0,the breakdown voltage of the laminate was 47 kV,and the thermal state flexural strength of the laminate was 596 MPa when the mass fraction of HPCTP in the laminate was 10%.
Hexaphenoxycyclotriphosphazene(HPCTP)was synthesized by the reaction of crude hexachloro-cyclotriphosphazene(HCCTP) with phenol and sodium hydroxide,with tetrabutylammonium chloride(TBAC) as phase transfer catalyst and chlorobenzene/water as solvent.Effects of reaction temperature,reaction time,solvent and molar ratio of raw matesials on the yield of HPCTP were investigated.Under the optimized reaction conditions of n(sodium hydroxide):n(phenol):n(TBAC):n(crude HCCTP)=7.5:6.3:0.15:1,reaction time of 4 h at 30℃ plus 6 h at reflux temperature,the yield was 75%.The product was characterized by FTIR,1H NMR,13C NMR,31P NMR,XRD,DSC and TGA.The product has been firstly applied in benzoxazine resin glass cloth laminate.The flammability class of the laminate was in the rank of V-0,the breakdown voltage of the laminate was 47 kV,and the thermal state flexural strength of the laminate was 596 MPa when the mass fraction of HPCTP in the laminate was 10%.
2010, 27(4): 409-412
doi: 10.3724/SP.J.1095.2010.90303
Abstract:
Three polymerizable nonionic surfactants(Ⅱ-PEG400,Ⅱ-PEG1000,Ⅱ-PEG2000) were synthesized from 2,4-toluene dissocyanate(TDI),allyl alcohol and polyethylene glycol,and characterized by FT-IR.Results indicate that as the molecular mass of polyethylene glycol increases,the conductance is increased obviously,and the surface tension is decreased from 36.28 mN/m to 31.30 mN/m, while the cloud point is increased from 39.6℃ to 58.9℃.Their emulsifying abilities to BA,MMA and BMA are superior to that of OP-10,and the surfactants is homopolymerize or copolymerize with acrylate at 70℃ under the initiation of AIBN.
Three polymerizable nonionic surfactants(Ⅱ-PEG400,Ⅱ-PEG1000,Ⅱ-PEG2000) were synthesized from 2,4-toluene dissocyanate(TDI),allyl alcohol and polyethylene glycol,and characterized by FT-IR.Results indicate that as the molecular mass of polyethylene glycol increases,the conductance is increased obviously,and the surface tension is decreased from 36.28 mN/m to 31.30 mN/m, while the cloud point is increased from 39.6℃ to 58.9℃.Their emulsifying abilities to BA,MMA and BMA are superior to that of OP-10,and the surfactants is homopolymerize or copolymerize with acrylate at 70℃ under the initiation of AIBN.
2010, 27(4): 413-417
doi: 10.3724/SP.J.1095.2010.90318
Abstract:
A series of radiopaque copolymers were synthesized via the free radical polymerization of 2-(2'-iodobenzoyl)ethyl methacrylate(2-IEMA) with butyl methacrylate(BMA).The compositions of 2-IEMA and BMA in the copolymers calculated by means of 1H NMR spectra were found to be in agreement with their feed molar ratios.The GPC analyses present that the Mn is decreased with the increase of 2-IEMA content.The DSC results imply that the Tg of the copolymers is between 22.3~28.0℃ which is in agreement with the result calculated by means of FOX equation,and the Tg of copolymers is increased with the increase of 2-IEMA content.The TGA measurements reveal that the thermal stability of the C-I bond endows the copolymers high thermal decomposition temperature.The mechanical testing shows that the tensile strength of the resulting copolymers is increased with the increase of BMA content with the maximum tensile strength reaching 7.46 MPa.These copolymers show the radiopacity as evidenced by X-ray fluoroscopy and their radiopacity is increased with the increase of 2-IEMA content.
A series of radiopaque copolymers were synthesized via the free radical polymerization of 2-(2'-iodobenzoyl)ethyl methacrylate(2-IEMA) with butyl methacrylate(BMA).The compositions of 2-IEMA and BMA in the copolymers calculated by means of 1H NMR spectra were found to be in agreement with their feed molar ratios.The GPC analyses present that the Mn is decreased with the increase of 2-IEMA content.The DSC results imply that the Tg of the copolymers is between 22.3~28.0℃ which is in agreement with the result calculated by means of FOX equation,and the Tg of copolymers is increased with the increase of 2-IEMA content.The TGA measurements reveal that the thermal stability of the C-I bond endows the copolymers high thermal decomposition temperature.The mechanical testing shows that the tensile strength of the resulting copolymers is increased with the increase of BMA content with the maximum tensile strength reaching 7.46 MPa.These copolymers show the radiopacity as evidenced by X-ray fluoroscopy and their radiopacity is increased with the increase of 2-IEMA content.
2010, 27(4): 418-423
doi: 10.3724/SP.J.1095.2010.90354
Abstract:
The composite of polyarylacetylene resin/fir powder was prepared by impregnating and thermoforming,and then a novel woodceramics was obtained by carbonizing the composite at high temperatures.Thermal stabilities of polyarylacetylene resin and the composite were analyzed by DTG.Influences of carbonization temperature and resin content on phase composition,pore morphology and compression strength were analyzed by XRD,LRS and SEM,respectively.The results show that the woodceramics was of a uniform three-dimensional porous structure.The decomposition temperature and char yield of the composite were 325℃ and 70% respectively.With increasing carbonization temperature,the(002) interlunar spacing decreased from 0.3895 nm to 0.3530 nm. However,the crystallite sizes Lc and La increased in different degrees.The open porosity of the woodceramics gradually decreased from 31.5% to 20.1% with the increase of carbonization temperature,while the compressive strength increased from 3.0 MPa to 6.2 MPa.The mass ratio of polyarylacetylene resin to fir powder had effect on the size and shape of the micropore of the woodceramics obviously,but a slight effect on the graphite crystallite size of the woodceramics.
The composite of polyarylacetylene resin/fir powder was prepared by impregnating and thermoforming,and then a novel woodceramics was obtained by carbonizing the composite at high temperatures.Thermal stabilities of polyarylacetylene resin and the composite were analyzed by DTG.Influences of carbonization temperature and resin content on phase composition,pore morphology and compression strength were analyzed by XRD,LRS and SEM,respectively.The results show that the woodceramics was of a uniform three-dimensional porous structure.The decomposition temperature and char yield of the composite were 325℃ and 70% respectively.With increasing carbonization temperature,the(002) interlunar spacing decreased from 0.3895 nm to 0.3530 nm. However,the crystallite sizes Lc and La increased in different degrees.The open porosity of the woodceramics gradually decreased from 31.5% to 20.1% with the increase of carbonization temperature,while the compressive strength increased from 3.0 MPa to 6.2 MPa.The mass ratio of polyarylacetylene resin to fir powder had effect on the size and shape of the micropore of the woodceramics obviously,but a slight effect on the graphite crystallite size of the woodceramics.
2010, 27(4): 424-427
doi: 10.3724/SP.J.1095.2010.90363
Abstract:
To search for the efficient biomimetic catalysts for the oxidation of hydrocarbon, cobalt deuteroporphyrin[Co(DPDME)] was used as catalyst for the oxidation of cyclohexane with air.The effects of reaction temperature,pressure of air,the catalyst amount and different complexes were evaluated.The experiment results show that Co(DPDME) is more effective than the others,and the optimum reaction conditions for the oxidation of cyclohexane are:c=0.015 mmol/L,reaction temperature 423 K,pressure of air 0.8 MPa,reaction time 5 h.Under the optimum conditions,the conversion rate of cyclohexane could reaches to 18.2%,the total selectivity of cyclohexanol and cyclohexanone is 87.4%.The temperature has much more influence on the catalytic reaction.Although the stability of Co(DPDME) was reduced when the temperature is higher than 443 K,the turnover number reaches 66 646.We also discussed the possible reaction path of Co(DPDME)-catalyzed oxidation of cyclohexane with oxygen.
To search for the efficient biomimetic catalysts for the oxidation of hydrocarbon, cobalt deuteroporphyrin[Co(DPDME)] was used as catalyst for the oxidation of cyclohexane with air.The effects of reaction temperature,pressure of air,the catalyst amount and different complexes were evaluated.The experiment results show that Co(DPDME) is more effective than the others,and the optimum reaction conditions for the oxidation of cyclohexane are:c=0.015 mmol/L,reaction temperature 423 K,pressure of air 0.8 MPa,reaction time 5 h.Under the optimum conditions,the conversion rate of cyclohexane could reaches to 18.2%,the total selectivity of cyclohexanol and cyclohexanone is 87.4%.The temperature has much more influence on the catalytic reaction.Although the stability of Co(DPDME) was reduced when the temperature is higher than 443 K,the turnover number reaches 66 646.We also discussed the possible reaction path of Co(DPDME)-catalyzed oxidation of cyclohexane with oxygen.
2010, 27(4): 428-431
doi: 10.3724/SP.J.1095.2010.90272
Abstract:
A series of supported ammonium molybdophosphat catalysts(AMPA/SiO2) with different loading was prepared from tetraethyl orthosilicate,ammonium molybdate and ammonium dihydrogen phosphate by sol-gel method.The samples were characterized by X-ray diffraction(XRD) and IR spectrometry.The catalytic activities of these catalysts were evaluated for the liquid phase nitration of benzene in 65% nitric acid without solvent at 70℃.Results indicate that supported catalyst still maintained the Keggin structure of ammonium molybdophosphate catalyst and exhibited high nitration reaction catalytic activity and high selectivity of mononitrobenzene.Among these catalysts,the catalyst with 10% loading showed maximum activity(96%),with 100% selectivity towards mononitrobenzene.The reusability of the catalysts was also studied,and it was found that there was no obvious change for catalyst phase and structure after being reused four times,although the active component had somewhat been lost in the reaction process.
A series of supported ammonium molybdophosphat catalysts(AMPA/SiO2) with different loading was prepared from tetraethyl orthosilicate,ammonium molybdate and ammonium dihydrogen phosphate by sol-gel method.The samples were characterized by X-ray diffraction(XRD) and IR spectrometry.The catalytic activities of these catalysts were evaluated for the liquid phase nitration of benzene in 65% nitric acid without solvent at 70℃.Results indicate that supported catalyst still maintained the Keggin structure of ammonium molybdophosphate catalyst and exhibited high nitration reaction catalytic activity and high selectivity of mononitrobenzene.Among these catalysts,the catalyst with 10% loading showed maximum activity(96%),with 100% selectivity towards mononitrobenzene.The reusability of the catalysts was also studied,and it was found that there was no obvious change for catalyst phase and structure after being reused four times,although the active component had somewhat been lost in the reaction process.
2010, 27(4): 432-436
doi: 10.3724/SP.J.1095.2010.90336
Abstract:
The nitration of methyl salicylate by iron(Ⅲ) nitrate was studied to obtain 3nitrosalicylate and 5-nitrosalicylate.The effects of reaction time,molar ratio of iron(Ⅲ) nitrate to methyl salicylate,acidity and basicity on the yield and regioselectivity were reported.When the reaction time is 3 h and the molar ratio of iron(Ⅲ) nitrate to methyl salicylate is 2:3,the yield is the highest.Furthermore,a small amount nitric acid is beneficial to the nitration and the formation of 5-nitrosalicylate,whereas a small amount base is not benefiical to the nitration but to the formation of 3-nitrosalicylate under a strong base condition.The regioselectivity was explained by the quatum chemical computations.
The nitration of methyl salicylate by iron(Ⅲ) nitrate was studied to obtain 3nitrosalicylate and 5-nitrosalicylate.The effects of reaction time,molar ratio of iron(Ⅲ) nitrate to methyl salicylate,acidity and basicity on the yield and regioselectivity were reported.When the reaction time is 3 h and the molar ratio of iron(Ⅲ) nitrate to methyl salicylate is 2:3,the yield is the highest.Furthermore,a small amount nitric acid is beneficial to the nitration and the formation of 5-nitrosalicylate,whereas a small amount base is not benefiical to the nitration but to the formation of 3-nitrosalicylate under a strong base condition.The regioselectivity was explained by the quatum chemical computations.
2010, 27(4): 437-440
doi: 10.3724/SP.J.1095.2010.90365
Abstract:
A series of supported catalysts was prepared by wetness impregnation method with TiO2 as substrate.The surface structures of the catalysts were characterized by XRD and IR.The catalysts prepared were used in the oxidation of p-cresol to p-hydroxybenzaldehyde.The results show that when the molar ratio of cobalt ions and copper ions was 1:0.5,the catalyst had the best catalytic effect.Under optimized reaction conditions,the conversion of p-cresol was nearly 100%,the selectivity of p-hydroxybenzaldehyde was 95.2%.
A series of supported catalysts was prepared by wetness impregnation method with TiO2 as substrate.The surface structures of the catalysts were characterized by XRD and IR.The catalysts prepared were used in the oxidation of p-cresol to p-hydroxybenzaldehyde.The results show that when the molar ratio of cobalt ions and copper ions was 1:0.5,the catalyst had the best catalytic effect.Under optimized reaction conditions,the conversion of p-cresol was nearly 100%,the selectivity of p-hydroxybenzaldehyde was 95.2%.
2010, 27(4): 441-444
doi: 10.3724/SP.J.1095.2010.90344
Abstract:
A trace amount of rare earth metal cation,e.g. Ce3+ was added to the activation solutions to enhance the electroless plating of Ag on Cu powder.Polarization curves of activation solutions,micromorphology and the clad ratio of silver on copper powder surface were studied through electrochemistry and scanning electron microscopy.The results show that the Ce3+ added to the Pd2+ activation solutions with an appropriate amount enables the decrease of polarizability,the increase of static potential and plating potential.Therefore,the reaction of activation solution became easier.A suitable amount of rare earth element can increase the deposition speed of silver on copper powder surface.With the further increase of rare earth element content,the particle size of silver plating on copper powder tend to dcrease and the coatings became clease gradually.The optimal addition value of Ce3+ is 0.32 g/L.
A trace amount of rare earth metal cation,e.g. Ce3+ was added to the activation solutions to enhance the electroless plating of Ag on Cu powder.Polarization curves of activation solutions,micromorphology and the clad ratio of silver on copper powder surface were studied through electrochemistry and scanning electron microscopy.The results show that the Ce3+ added to the Pd2+ activation solutions with an appropriate amount enables the decrease of polarizability,the increase of static potential and plating potential.Therefore,the reaction of activation solution became easier.A suitable amount of rare earth element can increase the deposition speed of silver on copper powder surface.With the further increase of rare earth element content,the particle size of silver plating on copper powder tend to dcrease and the coatings became clease gradually.The optimal addition value of Ce3+ is 0.32 g/L.
2010, 27(4): 445-448
doi: 10.3724/SP.J.1095.2010.90391
Abstract:
Using hexane as source material,carbon nanotubes(CNTs) were grown by chemical vapor deposition process on layered double hydroxides(LDHs) containing similar amounts of iron,cobalt or nickel as catalysts. Catalysts were obtained by calcination of LDH precursors followed by reduction. The materials were characterized by X-ray diffractometry,scaning electron microscopy, transmission electron microscopy and Raman spectroscopy.The results indicated that all CNTs exhibited are multi-walled CNTs. The activity order of these three catalysts is nickel > iron > cobalt. The CNTs grown on cobalt catalyst have a smaller diameter and contain more graphite, while the CNTs grown on nickel catalyst have a higher density,a thicker wall and less graphite.The activity of catalyst and density of CNTs mainly could be interpreted from on the structure of CNTs.
Using hexane as source material,carbon nanotubes(CNTs) were grown by chemical vapor deposition process on layered double hydroxides(LDHs) containing similar amounts of iron,cobalt or nickel as catalysts. Catalysts were obtained by calcination of LDH precursors followed by reduction. The materials were characterized by X-ray diffractometry,scaning electron microscopy, transmission electron microscopy and Raman spectroscopy.The results indicated that all CNTs exhibited are multi-walled CNTs. The activity order of these three catalysts is nickel > iron > cobalt. The CNTs grown on cobalt catalyst have a smaller diameter and contain more graphite, while the CNTs grown on nickel catalyst have a higher density,a thicker wall and less graphite.The activity of catalyst and density of CNTs mainly could be interpreted from on the structure of CNTs.
2010, 27(4): 449-453
doi: 10.3724/SP.J.1095.2010.90324
Abstract:
Sequential growth of magic sized semiconductor nanoclusters(CdSe) was realized in noncoordination solvent 1-octadecene(ODE) with 1-dodecanethiol(DDT) as "nucleating agent",dodecylamine(DDA) as "activating agent",cadmium fatty acid salts and ODE-Se as precursors.The obtained CdSe nanoclusters were characterized by transmission electron microscopy(TEM),ultraviolet-visible absorption(UV-Vis abs) spectroscopy,photoluminescence excitation(PLE),photoluminescence(PL) spectroscopy and time-resolved fluorescence spectroscopy.CdSe nanoclusters possess excellent room temperature photoluminescence properties.The PL spectra,which can only be obtained at low temperature(5~200 K) previously,can be easily measured at room temperature.Most of the emission spectra were induced by the surface traps and located in the yellow color region.Parts of nanoclusters can exhibit white color emission,whose CIE coordinate is x=0.339 and y=0.340.They will provide alternative materials for white color devices.
Sequential growth of magic sized semiconductor nanoclusters(CdSe) was realized in noncoordination solvent 1-octadecene(ODE) with 1-dodecanethiol(DDT) as "nucleating agent",dodecylamine(DDA) as "activating agent",cadmium fatty acid salts and ODE-Se as precursors.The obtained CdSe nanoclusters were characterized by transmission electron microscopy(TEM),ultraviolet-visible absorption(UV-Vis abs) spectroscopy,photoluminescence excitation(PLE),photoluminescence(PL) spectroscopy and time-resolved fluorescence spectroscopy.CdSe nanoclusters possess excellent room temperature photoluminescence properties.The PL spectra,which can only be obtained at low temperature(5~200 K) previously,can be easily measured at room temperature.Most of the emission spectra were induced by the surface traps and located in the yellow color region.Parts of nanoclusters can exhibit white color emission,whose CIE coordinate is x=0.339 and y=0.340.They will provide alternative materials for white color devices.
2010, 27(4): 454-457
doi: 10.3724/SP.J.1095.2010.90328
Abstract:
The nanoparticles of NiO precursor were prepared by a low temperature solid state reaction under ultrasonic airflow.The precursor was converted into NiO nanorods after annealing at 650~900℃ in a molten salt medium.The structure and morphology of NiO precursor and nanorods were investigated by XRD,SEM and TEM technologies.The results indicated that the prepared precursor was spheric particles with a diameter of about 25 nm,and grew gradually to NiO nanorods with a diameter of about 300 nm and a length of several micrometers along with rising calcinging temperatures.The key factor in the process for the grwoth of NiO nanorods is the molten salt medium.
The nanoparticles of NiO precursor were prepared by a low temperature solid state reaction under ultrasonic airflow.The precursor was converted into NiO nanorods after annealing at 650~900℃ in a molten salt medium.The structure and morphology of NiO precursor and nanorods were investigated by XRD,SEM and TEM technologies.The results indicated that the prepared precursor was spheric particles with a diameter of about 25 nm,and grew gradually to NiO nanorods with a diameter of about 300 nm and a length of several micrometers along with rising calcinging temperatures.The key factor in the process for the grwoth of NiO nanorods is the molten salt medium.
2010, 27(4): 458-461
doi: 10.3724/SP.J.1095.2010.90246
Abstract:
Lignin was extracted from carrot root with high boiling solvent(HBS) 80% ethylene glycol aqueous solution as solvent.Results show that the optimum conditions were as follows:the mass ratio of raw solid materials to solvent was 1:6,temperature was 210℃,reaction time was 2 h,the maximum yield was 17.79%. The chemical structure of the carrot lignin has been characterized by FTIR, UV,and 1H NMR.The chemical composition of HBS lignin from carrot root was determined by elemental analysis,and the content of methoxyl was tested with Vieböck's methods. The C9 structure of lignin from carrot was estimated as C9H9.62O1.99(OCH3)1.96.The elimination efficiency of·OH free radical by lignin from carrot was studied.The results show that carrot lignin can inhibit the activity of·OH free radical at low concentrations(50 mg/L)with a maximum inhibition efficiency of 64.9%.
Lignin was extracted from carrot root with high boiling solvent(HBS) 80% ethylene glycol aqueous solution as solvent.Results show that the optimum conditions were as follows:the mass ratio of raw solid materials to solvent was 1:6,temperature was 210℃,reaction time was 2 h,the maximum yield was 17.79%. The chemical structure of the carrot lignin has been characterized by FTIR, UV,and 1H NMR.The chemical composition of HBS lignin from carrot root was determined by elemental analysis,and the content of methoxyl was tested with Vieböck's methods. The C9 structure of lignin from carrot was estimated as C9H9.62O1.99(OCH3)1.96.The elimination efficiency of·OH free radical by lignin from carrot was studied.The results show that carrot lignin can inhibit the activity of·OH free radical at low concentrations(50 mg/L)with a maximum inhibition efficiency of 64.9%.
2010, 27(4): 462-465
doi: 10.3724/SP.J.1095.2010.90007
Abstract:
The deacetylations(DD) of chitosan and chitooligosaccharide(COS) were estimated by titration of acid-base method as 90.9% and 90.1%,respectively.After Sephadex chromatography purification,the degree of polymerization(DP) and DD were obtained by MALDI-FT-MS.It was found that chitosan has high an adsorption of the radionuclide uranium.Chitosan showed high adsorption of radionuclide uranium even with the presence of large amount of Cu2+ ions.The adsorption efficiency is above 96%.This shows that chitosan has a great potential for the renoval of both heavy metals and radionuclides.
The deacetylations(DD) of chitosan and chitooligosaccharide(COS) were estimated by titration of acid-base method as 90.9% and 90.1%,respectively.After Sephadex chromatography purification,the degree of polymerization(DP) and DD were obtained by MALDI-FT-MS.It was found that chitosan has high an adsorption of the radionuclide uranium.Chitosan showed high adsorption of radionuclide uranium even with the presence of large amount of Cu2+ ions.The adsorption efficiency is above 96%.This shows that chitosan has a great potential for the renoval of both heavy metals and radionuclides.
2010, 27(4): 466-469
doi: 10.3724/SP.J.1095.2010.90364
Abstract:
The isotherms and the amount of adsorption of pentadecyl aryl sulfonates with high purity synthesized in our laboratory on oil sands were determined at 45℃.The effects of the concentrations of surfactants,NaCl,NaOH,NaHCO3,n-butyl alcohol and molecular structures of surfactants on pentadecyl aryl sulfonate adsorption were investigated.The experimental results show that with increasing the concentrations of the sulfonates,the absorption capacity was firstly increased,and then decreased.The absorption capacity increased with the addition of NaCl and NaOH while decreased with the addition of n-butyl alcohol and NaHCO3. Moving the aryl from the terminal to the center of the long alkyl chain,the absorption capacity decreased,and the impact of accessory was reduced.
The isotherms and the amount of adsorption of pentadecyl aryl sulfonates with high purity synthesized in our laboratory on oil sands were determined at 45℃.The effects of the concentrations of surfactants,NaCl,NaOH,NaHCO3,n-butyl alcohol and molecular structures of surfactants on pentadecyl aryl sulfonate adsorption were investigated.The experimental results show that with increasing the concentrations of the sulfonates,the absorption capacity was firstly increased,and then decreased.The absorption capacity increased with the addition of NaCl and NaOH while decreased with the addition of n-butyl alcohol and NaHCO3. Moving the aryl from the terminal to the center of the long alkyl chain,the absorption capacity decreased,and the impact of accessory was reduced.
2010, 27(4): 470-473
doi: 10.3724/SP.J.1095.2010.90515
Abstract:
The rheology of hexaflumuron in the form of aqueous suspension concentrate(SC) was studied by means of controlled stress rheometer,with the particular emphasis on the effects of polymer dispersant MOTAS (Styrene-acrylic acid random copolymer) mass concentrations,molecular mass and hexaflumuron mass concentrations.It was found that the rheological behavior of hexaflumuron SC,which contained MOTAS,coincided with the Herschel-Bulkley rheological model.For a hexaflumuron mass concentration of 20%,the SC was pseudoplastic fluid and the flow behavior index n ≤ 1.0 when the MOTAS mass fraction was less than 3.0%; the SC was bulging plastic fluid and the flow behavior index n ≥ 1.0 while the MOTAS mass fraction was more than 3.0%.The yield value τH of hexaflumuron SC was correlated with the relative mass fractions of MOTAS and hexaflumuron.Little MOTAS was adsorbed on the hexaflumuron granule surface in its concentration ≤ 2.5%,and the uncoverd granules were connected with each other in some structures,which resulted in the biggist τH.When MOTAS mass fraction was 3.0%,saturated adsorption was achieved on the granule surfaces.The excessive MOTAS connected with each other in some structures,which produced the biggist τH likewise.Between dispersant MOTAS molecular mass 10 000 and 30 000,with the increase of MOTAS molecular mass,the viscidity and yield value τH of hexaflumuron SC decreased,while the flow behavior index n increased slightly.The n values were all less than 1,and the property of "shear thinning" of the pseudo-plasticity was not changed.
The rheology of hexaflumuron in the form of aqueous suspension concentrate(SC) was studied by means of controlled stress rheometer,with the particular emphasis on the effects of polymer dispersant MOTAS (Styrene-acrylic acid random copolymer) mass concentrations,molecular mass and hexaflumuron mass concentrations.It was found that the rheological behavior of hexaflumuron SC,which contained MOTAS,coincided with the Herschel-Bulkley rheological model.For a hexaflumuron mass concentration of 20%,the SC was pseudoplastic fluid and the flow behavior index n ≤ 1.0 when the MOTAS mass fraction was less than 3.0%; the SC was bulging plastic fluid and the flow behavior index n ≥ 1.0 while the MOTAS mass fraction was more than 3.0%.The yield value τH of hexaflumuron SC was correlated with the relative mass fractions of MOTAS and hexaflumuron.Little MOTAS was adsorbed on the hexaflumuron granule surface in its concentration ≤ 2.5%,and the uncoverd granules were connected with each other in some structures,which resulted in the biggist τH.When MOTAS mass fraction was 3.0%,saturated adsorption was achieved on the granule surfaces.The excessive MOTAS connected with each other in some structures,which produced the biggist τH likewise.Between dispersant MOTAS molecular mass 10 000 and 30 000,with the increase of MOTAS molecular mass,the viscidity and yield value τH of hexaflumuron SC decreased,while the flow behavior index n increased slightly.The n values were all less than 1,and the property of "shear thinning" of the pseudo-plasticity was not changed.
2010, 27(4): 474-477
doi: 10.3724/SP.J.1095.2010.90356
Abstract:
A series of 3-diferrocenyl dihydropyrazole derivatives were synthesized from acetylferrocene.The structures of these compounds were characterized by IR,1H NMR and MS.The crystal structure of compound 22 was determined via X-ray single-crystal diffraction.Compound 22 belongs to the triclinic system with space group P1,and the unit cell parameters are a=0.9275(4) nm,b=1.1327(5) nm, c=1.1912(5) nm, α=88.67(2)°,β=79.925(18)°,γ=70.345(18)°, V=1.1595(9)nm3, Z=2,F(000)=560, Dc=1.553g/cm3, μ=1.279mm-1,R1=0.0351,wR2=0.0934.
A series of 3-diferrocenyl dihydropyrazole derivatives were synthesized from acetylferrocene.The structures of these compounds were characterized by IR,1H NMR and MS.The crystal structure of compound 22 was determined via X-ray single-crystal diffraction.Compound 22 belongs to the triclinic system with space group P1,and the unit cell parameters are a=0.9275(4) nm,b=1.1327(5) nm, c=1.1912(5) nm, α=88.67(2)°,β=79.925(18)°,γ=70.345(18)°, V=1.1595(9)nm3, Z=2,F(000)=560, Dc=1.553g/cm3, μ=1.279mm-1,R1=0.0351,wR2=0.0934.
2010, 27(4): 478-483
doi: 10.3724/SP.J.1095.2010.90351
Abstract:
A new corrosion inhibitor and universal antibacterial reagent,namely,the copolymer of N-isopropylacrylamide(NIPAM) and N-allyl-1-benzoyl-3-phenyl-4,5-dihydro-4-formamido pyrazole(BPCP) was prepared.Its inhibitory effect on the corrosion of N80 steel panel in 1 molar hydrochloric acid solution was investigated at room temperature via the static mass-loss method,and the adsorption of the copolymer molecules on the surface of N80 steel panel was studied through electrochemical impedance spectroscopy(EIS). Minimal inhibitory concentration(MIC) of the copolymer for different kinds of bacterials was determined with the liquor dilution approach.Results obtained from the experiments indicate that the copolymer is an efficient chemical corrosion inhibitor for N80 steel panel in 1 mol/L HCl solution.The inhibition efficiency of the copolymer increases with the increase in inhibitor concentration within a mass content range from 0.5 g/L to 7.0 g/L,reaching the maximum value of 90.3% at a inhibitor concentration of 6 g/L,only half of the amount of the reported inhibitor in the literature,1/10 of the amount of small molecule inhibitor NABPPAA.Adsorption of copolymer on N80 steel panel's surface follows Langmuir's isotherm within experimental mass concentration range.Calculated adsorption enthalpy of the copolymer on N80 steel panel surface is 30.446 kJ/mol.Its adsorption model can be mainly ascribed to the chemical nature of adsorption(chemisorptions) according to the adsorption enthalpy.Large and persistant inhibitory effect of the copolymer on N80 steel erosion in acid solution is observed within a temperature range of 25~80℃.The results reveal that the copolymer has a broad inhibitory and a good germicidal effect on several kinds of bacteria.
A new corrosion inhibitor and universal antibacterial reagent,namely,the copolymer of N-isopropylacrylamide(NIPAM) and N-allyl-1-benzoyl-3-phenyl-4,5-dihydro-4-formamido pyrazole(BPCP) was prepared.Its inhibitory effect on the corrosion of N80 steel panel in 1 molar hydrochloric acid solution was investigated at room temperature via the static mass-loss method,and the adsorption of the copolymer molecules on the surface of N80 steel panel was studied through electrochemical impedance spectroscopy(EIS). Minimal inhibitory concentration(MIC) of the copolymer for different kinds of bacterials was determined with the liquor dilution approach.Results obtained from the experiments indicate that the copolymer is an efficient chemical corrosion inhibitor for N80 steel panel in 1 mol/L HCl solution.The inhibition efficiency of the copolymer increases with the increase in inhibitor concentration within a mass content range from 0.5 g/L to 7.0 g/L,reaching the maximum value of 90.3% at a inhibitor concentration of 6 g/L,only half of the amount of the reported inhibitor in the literature,1/10 of the amount of small molecule inhibitor NABPPAA.Adsorption of copolymer on N80 steel panel's surface follows Langmuir's isotherm within experimental mass concentration range.Calculated adsorption enthalpy of the copolymer on N80 steel panel surface is 30.446 kJ/mol.Its adsorption model can be mainly ascribed to the chemical nature of adsorption(chemisorptions) according to the adsorption enthalpy.Large and persistant inhibitory effect of the copolymer on N80 steel erosion in acid solution is observed within a temperature range of 25~80℃.The results reveal that the copolymer has a broad inhibitory and a good germicidal effect on several kinds of bacteria.
2010, 27(4): 484-487
doi: 10.3724/SP.J.1095.2010.90252
Abstract:
A simple decolouring spectrophotometric method for the determination of methanol was developed in this work.A russety product can be formed by the reaction between Lysine(Lys) and sodium 1,2-naphthoquinone-4-sulfonate(NQS) in an alkaline solution.When methanol was added to the solution,the system involves decolouring process.Beer's law is held in a range of methanol concentration of 0.050~7.61 g/L at a maximal decolouring wavelength of 559 nm.The equation of linear regression is A=-0.00517-0.08679c(g/L),with a linearly correlation coefficient of 0.9996.The detection limit of methanol is 49.5 mg/L(3σ) and the recovery rate is in a range of 99.1%~102.6%.Analytical results obtained with this method are satisfactory.
A simple decolouring spectrophotometric method for the determination of methanol was developed in this work.A russety product can be formed by the reaction between Lysine(Lys) and sodium 1,2-naphthoquinone-4-sulfonate(NQS) in an alkaline solution.When methanol was added to the solution,the system involves decolouring process.Beer's law is held in a range of methanol concentration of 0.050~7.61 g/L at a maximal decolouring wavelength of 559 nm.The equation of linear regression is A=-0.00517-0.08679c(g/L),with a linearly correlation coefficient of 0.9996.The detection limit of methanol is 49.5 mg/L(3σ) and the recovery rate is in a range of 99.1%~102.6%.Analytical results obtained with this method are satisfactory.
2010, 27(4): 488-493
doi: 10.3724/SP.J.1095.2010.90362
Abstract:
A method was developed for the simultaneous determination of 19 carbamate pesticides residues in spinach, cucumber, scallion, fungus, mushroom, agaric and carrot by ultra performance liquid chromatography tandem mass spectrometry(UPLCMS/MS) combined with isotope internal standard method. The vegetable and mushroom samples were extracted with V(acetone):V(acetonitrile)=85:15 then purified by gel permeation chromatography(GPC) or solid phase extraction(SPE). The recoveries ranged from 70.1% to 95.7% with the cleaning method of GPC and from 70.2% to 94.9% with the cleaning method of primary-secondary amine(PSA) SPE. The limits of detection(LOD) were 1×10-5g/kg. The method showed a good linear relationship with the correlation coefficients over 0.99. This method is practical,accurate and highly sensitive.
A method was developed for the simultaneous determination of 19 carbamate pesticides residues in spinach, cucumber, scallion, fungus, mushroom, agaric and carrot by ultra performance liquid chromatography tandem mass spectrometry(UPLCMS/MS) combined with isotope internal standard method. The vegetable and mushroom samples were extracted with V(acetone):V(acetonitrile)=85:15 then purified by gel permeation chromatography(GPC) or solid phase extraction(SPE). The recoveries ranged from 70.1% to 95.7% with the cleaning method of GPC and from 70.2% to 94.9% with the cleaning method of primary-secondary amine(PSA) SPE. The limits of detection(LOD) were 1×10-5g/kg. The method showed a good linear relationship with the correlation coefficients over 0.99. This method is practical,accurate and highly sensitive.
2010, 27(4): 494-496
doi: 10.3724/SP.J.1095.2010.90420
Abstract:
5-Methyl-2,3-diphenyl-1,5-benzothiazepin-4(5H)-one was synthesized via the acylation reaction and iodocyclization reaction and Suzuki cross-coupling reaction with 2-(methylthio)aniline as the initial material.Effects including catalysts on acylation reaction,solvents on iodocyclization and catalysts,ligand,base and reaction temperature on Suzuki cross-coupling reaction have been investigated.Under optimum conditions,the yield of the product was up to 68.5%.The chemical structures of the intermediates and target product were characterized by IR,NMR and MS spectra.
5-Methyl-2,3-diphenyl-1,5-benzothiazepin-4(5H)-one was synthesized via the acylation reaction and iodocyclization reaction and Suzuki cross-coupling reaction with 2-(methylthio)aniline as the initial material.Effects including catalysts on acylation reaction,solvents on iodocyclization and catalysts,ligand,base and reaction temperature on Suzuki cross-coupling reaction have been investigated.Under optimum conditions,the yield of the product was up to 68.5%.The chemical structures of the intermediates and target product were characterized by IR,NMR and MS spectra.
