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2005 Volume 22 Issue 3
2005, 22(3): 233-237
Abstract:
Two kinds of photo chemical pH sensing membranes PECM and PFCM,for optic pH sensors,with epichlorohydrin cross-linked PVA and formaldehyde cross-linked PVA gel as matrices are described.Their pH linear response ranges are within 2 mol/L[H+]~pH 6.8 and pH 2.9~pH 5.4,respectively.The response time of both the membranes is less than 10 s when ΔpH is within 2 pH units.Experimental results show they have good reproducibility and reversibility.
Two kinds of photo chemical pH sensing membranes PECM and PFCM,for optic pH sensors,with epichlorohydrin cross-linked PVA and formaldehyde cross-linked PVA gel as matrices are described.Their pH linear response ranges are within 2 mol/L[H+]~pH 6.8 and pH 2.9~pH 5.4,respectively.The response time of both the membranes is less than 10 s when ΔpH is within 2 pH units.Experimental results show they have good reproducibility and reversibility.
2005, 22(3): 238-241
Abstract:
The metallofullerenes were synthesized by the arc-discharging method with GdNi2 alloy as the metal source.LDI-TOF mass spectrometry was used to characterize the toluene extracts and high temperature high pressure pyridine extracts.When x(Gd):x(C)=1:50,I=90 A,U=25 V,He pressure was 40 kPa and the gap between the anode and cathode was 8 mm,metallofullerene was obtained in a yield of 2.54%.
The metallofullerenes were synthesized by the arc-discharging method with GdNi2 alloy as the metal source.LDI-TOF mass spectrometry was used to characterize the toluene extracts and high temperature high pressure pyridine extracts.When x(Gd):x(C)=1:50,I=90 A,U=25 V,He pressure was 40 kPa and the gap between the anode and cathode was 8 mm,metallofullerene was obtained in a yield of 2.54%.
2005, 22(3): 242-245
Abstract:
Beryllon Ⅱ interacts with protein to form a supermolecular complex in a pH 4.3 Britton-Robinson (B-R) buffer solution and produces a sensitive reduction peak at -0.48 V (vs.SCE) on the hanging mercury drop electrode.According to the decrease of the reduction peak current without the shifting of the peak potential of beryllon Ⅱ after the addition of human serum albumin (HSA) to the above solution,a new linear sweep voltammetric determination method for protein is proposed.Under the optimal electrochemical conditions,the reduction peak current of beryllon Ⅱ decreases linearly with the HSA concentration ranged from 5.0 to 50.0 mg/L and the linear regression equation is Δi"p(nA)=49.83+3.65c(mg/L),γ=0.996 6.The method was applied to determine the content of HSA in human blood samples and the result was in good agreement with that obtained by the traditional Coomassie brilliant blue G-250 spectrophotometric method.The method was also used to determine bovine serum album in,bovine hemoglobin with satisfactory results.
Beryllon Ⅱ interacts with protein to form a supermolecular complex in a pH 4.3 Britton-Robinson (B-R) buffer solution and produces a sensitive reduction peak at -0.48 V (vs.SCE) on the hanging mercury drop electrode.According to the decrease of the reduction peak current without the shifting of the peak potential of beryllon Ⅱ after the addition of human serum albumin (HSA) to the above solution,a new linear sweep voltammetric determination method for protein is proposed.Under the optimal electrochemical conditions,the reduction peak current of beryllon Ⅱ decreases linearly with the HSA concentration ranged from 5.0 to 50.0 mg/L and the linear regression equation is Δi"p(nA)=49.83+3.65c(mg/L),γ=0.996 6.The method was applied to determine the content of HSA in human blood samples and the result was in good agreement with that obtained by the traditional Coomassie brilliant blue G-250 spectrophotometric method.The method was also used to determine bovine serum album in,bovine hemoglobin with satisfactory results.
2005, 22(3): 246-249
Abstract:
Two rare earth complexes with formula [Ln2(H2O)4(Ts-β-Ala-)6]n·4nH2O (where Ln=Pr (1),Yb (2),Ts-β-Ala-=N-p-tolysulfonyl-β-Alanine anion) were prepared and their crystal structures were determined by X-ray diffract ometry.Both the complexes are monoclinic,with space group P21/n.The crystal data are:(1):a=0.953 2(3) nm,b=1.909 5(6) nm,c=2.298 0(8) nm,β=99.73(2)°,Z=4,Dc=1.514×10-3 g/cm3;(2):a=0.956 9(1) nm,b=1.888 0(3) nm,c=2.286 8(3) nm,β=100.41(1)°,Z=4,Dc=1.589×10-3 g/cm3.The two complexes in crystal have one-dimensional chain structures and are different in bridging type of carboxyl groups.The coordination number of the PrⅢ ion is nine and that of the YbⅢ ion is eight.The complexes have stronger antibacterial activity than the ligand does.
Two rare earth complexes with formula [Ln2(H2O)4(Ts-β-Ala-)6]n·4nH2O (where Ln=Pr (1),Yb (2),Ts-β-Ala-=N-p-tolysulfonyl-β-Alanine anion) were prepared and their crystal structures were determined by X-ray diffract ometry.Both the complexes are monoclinic,with space group P21/n.The crystal data are:(1):a=0.953 2(3) nm,b=1.909 5(6) nm,c=2.298 0(8) nm,β=99.73(2)°,Z=4,Dc=1.514×10-3 g/cm3;(2):a=0.956 9(1) nm,b=1.888 0(3) nm,c=2.286 8(3) nm,β=100.41(1)°,Z=4,Dc=1.589×10-3 g/cm3.The two complexes in crystal have one-dimensional chain structures and are different in bridging type of carboxyl groups.The coordination number of the PrⅢ ion is nine and that of the YbⅢ ion is eight.The complexes have stronger antibacterial activity than the ligand does.
2005, 22(3): 250-254
Abstract:
Poly (propylene-co-γ-butyrolactone carbonate) PPCG was synthesized from carbon dioxide,1,2-propylene oxide (PO) and γ-butyrolactone (GBL).The PPCG-dextrose microcapsules were prepared by the diphase emulsion method with gelatin as stabilizer.The structure of the copolymer was characterized by FT IR,1H NMR and 13C NMR.The PPCG was found to be more degradable than polyethylene carbonate (PPC) and could be used in fabrication of microcapsules for long-term drug-releasing technique.The SEM photos indicate that the micro capsules have a smooth and spherical surface sized between 2~2.5 μm.The influences of V(PPCG):V(dextrose),gelatin concentration and preparation process on microcapsules size,drug loading and encapsulation efficiency were studied.When V(PPCG):V(dextrose) is 1:2,ω(gelatin)=0.2%,the first stirring rate 500 r/min,the second stirring rate 400 r/min and stirring time 6 h,the resulting microcapsules have drug loading of 36.7%,encapsulation efficiency of 84.6% and smaller particle size.
Poly (propylene-co-γ-butyrolactone carbonate) PPCG was synthesized from carbon dioxide,1,2-propylene oxide (PO) and γ-butyrolactone (GBL).The PPCG-dextrose microcapsules were prepared by the diphase emulsion method with gelatin as stabilizer.The structure of the copolymer was characterized by FT IR,1H NMR and 13C NMR.The PPCG was found to be more degradable than polyethylene carbonate (PPC) and could be used in fabrication of microcapsules for long-term drug-releasing technique.The SEM photos indicate that the micro capsules have a smooth and spherical surface sized between 2~2.5 μm.The influences of V(PPCG):V(dextrose),gelatin concentration and preparation process on microcapsules size,drug loading and encapsulation efficiency were studied.When V(PPCG):V(dextrose) is 1:2,ω(gelatin)=0.2%,the first stirring rate 500 r/min,the second stirring rate 400 r/min and stirring time 6 h,the resulting microcapsules have drug loading of 36.7%,encapsulation efficiency of 84.6% and smaller particle size.
2005, 22(3): 255-258
Abstract:
The urushiol-formaldehyde polymer (UFP) coating was modified with multihydroxyl polyacrylate (MPA) to prepare the interpenetrating polymer network (IPN) of UFP/MPA.The structure and mechanical property of the IPNs were examined by IR,TG/DSC and DMTA.The results show that the IPN was formed by the cross-linking and entanglement of UFP and MPA at m(UFP):m(MPA)=5:2 and exhibited the charac-teristic of both UFP and MPA coatings,i.e.,heat resistance and solvent resistance with pencil hardness of 6H,adhesion of 1 grade and flexibility (1 mm) after irradiation with ultraviolet light for 7 days.
The urushiol-formaldehyde polymer (UFP) coating was modified with multihydroxyl polyacrylate (MPA) to prepare the interpenetrating polymer network (IPN) of UFP/MPA.The structure and mechanical property of the IPNs were examined by IR,TG/DSC and DMTA.The results show that the IPN was formed by the cross-linking and entanglement of UFP and MPA at m(UFP):m(MPA)=5:2 and exhibited the charac-teristic of both UFP and MPA coatings,i.e.,heat resistance and solvent resistance with pencil hardness of 6H,adhesion of 1 grade and flexibility (1 mm) after irradiation with ultraviolet light for 7 days.
2005, 22(3): 259-263
Abstract:
Polymer-bound metalloporphyrins with polyglycol chains were synthesized and their catalytic performances on the oxidation of cyclohexene were investigated.The experimental results show that the synthesized manganese (Ⅱ) and cobalt (Ⅱ) porphyrins bound to chloromethylated polystyrene with polyglycol chains are efficient catalysts for the oxidation of cyclohexene.The conversion is 88% for the oxidation of cyclohexene catalyzed by manganese (Ⅱ) porphyrin bound to chloro-methylated polystyrene.The catalytic performances of synthesized manganese (Ⅱ) and cobalt (Ⅱ) porphyrins are better than those of simple metalloporphyrins;however,the catalytic performance of polymer-bound metalloporphyrins with phase transfer catalyst polyglycol chains are decreased.
Polymer-bound metalloporphyrins with polyglycol chains were synthesized and their catalytic performances on the oxidation of cyclohexene were investigated.The experimental results show that the synthesized manganese (Ⅱ) and cobalt (Ⅱ) porphyrins bound to chloromethylated polystyrene with polyglycol chains are efficient catalysts for the oxidation of cyclohexene.The conversion is 88% for the oxidation of cyclohexene catalyzed by manganese (Ⅱ) porphyrin bound to chloro-methylated polystyrene.The catalytic performances of synthesized manganese (Ⅱ) and cobalt (Ⅱ) porphyrins are better than those of simple metalloporphyrins;however,the catalytic performance of polymer-bound metalloporphyrins with phase transfer catalyst polyglycol chains are decreased.
2005, 22(3): 264-267
Abstract:
A linear photosensitive polyester was synthesized from p-phenylenediacrylic dichloride and 4,4'-(hexafluoroisopropylidene) diphenol,and the photoalignment films of nematic liquid crystals were prepared by using the polyester.The film became anisotropic after being irradiated by linear polarized UV,and the reaction mechanisms were investigated by UV-Vis and IR.A parallel liquid crystal cell was fabricated with the photoalignment film.Polarized optical microscopy indicates that the alignment of liquid crystals is uniform and stable.The pretilt angle of the photoalignment film is 2°~3°,and the alignment could be maintained at up to 130℃.
A linear photosensitive polyester was synthesized from p-phenylenediacrylic dichloride and 4,4'-(hexafluoroisopropylidene) diphenol,and the photoalignment films of nematic liquid crystals were prepared by using the polyester.The film became anisotropic after being irradiated by linear polarized UV,and the reaction mechanisms were investigated by UV-Vis and IR.A parallel liquid crystal cell was fabricated with the photoalignment film.Polarized optical microscopy indicates that the alignment of liquid crystals is uniform and stable.The pretilt angle of the photoalignment film is 2°~3°,and the alignment could be maintained at up to 130℃.
2005, 22(3): 268-271
Abstract:
The surface micromorphologies,microhardnesses and wear volumes of chemical plating Co-Ni-B-Ce alloy obtained under a magnetic field were studied.The results show that the surface of Co-Ni-B coating was composed of "taper humps",the surface felt smooth,and became irregular when the plating was carried out in the plating bath containing the cerium compound.The surface "taper humps" of the Co-Ni-B-Ce alloy coatings were much more irregular when the plating was carried out under magnetic field.The microhardness and wear resistance of Co-Ni-B alloy coatings are remarkably increased when cerium chloride added in the plating bath and the plating process is performed under a magnetic field.With increasing of cerium amount in the plating bath,both the micro hardness and wear resistance of the alloy coatings increase first and decrease afterwards,and both reach to their peak values at c(Ce)=0.8 g/L in the plating bath.
The surface micromorphologies,microhardnesses and wear volumes of chemical plating Co-Ni-B-Ce alloy obtained under a magnetic field were studied.The results show that the surface of Co-Ni-B coating was composed of "taper humps",the surface felt smooth,and became irregular when the plating was carried out in the plating bath containing the cerium compound.The surface "taper humps" of the Co-Ni-B-Ce alloy coatings were much more irregular when the plating was carried out under magnetic field.The microhardness and wear resistance of Co-Ni-B alloy coatings are remarkably increased when cerium chloride added in the plating bath and the plating process is performed under a magnetic field.With increasing of cerium amount in the plating bath,both the micro hardness and wear resistance of the alloy coatings increase first and decrease afterwards,and both reach to their peak values at c(Ce)=0.8 g/L in the plating bath.
2005, 22(3): 272-277
Abstract:
A series of novel Schiff base crown ether liquid crystals were synthesized from intermediates 4-(4'-alkoxylbiphenyl-4-carboxyl) benzaldehyde and diaminodibenzo-15-crown-5 in yields of 95.2%~96.7%,and their structures and properties were characterized by elemental analysis,polarimetry,1H NMR,IR,MALDI-TOF-MS,DSC and polarizing optical microscopy with a heating stage.It was found that end products 6Ⅰ and 6Ⅱ formed liquid crystalline phase when heated to their melting points.In their liquid crystalline state,typical chiral smectic C phase,smectic phase,cholesteric phase,and nematic phase textures can be observed.The smectic phase temperature range increases,but the smectic-nematic transition temperature and nemetic phase temperature rang decrease with the increasing of the carbon number of end alkoxy groups,and the melting point (Tm) and isotropization temperature (Ti) decrease gradually.
A series of novel Schiff base crown ether liquid crystals were synthesized from intermediates 4-(4'-alkoxylbiphenyl-4-carboxyl) benzaldehyde and diaminodibenzo-15-crown-5 in yields of 95.2%~96.7%,and their structures and properties were characterized by elemental analysis,polarimetry,1H NMR,IR,MALDI-TOF-MS,DSC and polarizing optical microscopy with a heating stage.It was found that end products 6Ⅰ and 6Ⅱ formed liquid crystalline phase when heated to their melting points.In their liquid crystalline state,typical chiral smectic C phase,smectic phase,cholesteric phase,and nematic phase textures can be observed.The smectic phase temperature range increases,but the smectic-nematic transition temperature and nemetic phase temperature rang decrease with the increasing of the carbon number of end alkoxy groups,and the melting point (Tm) and isotropization temperature (Ti) decrease gradually.
2005, 22(3): 278-281
Abstract:
Thirteen N-(1,3,4-thiodiazol-2-y1)-N'-aroyl ureas were synthesized by the reaction of aroyl iso-cyanates with 2-amino-1,3,4-thiodiazole in yields of 54.5%~86.2%.The structures of the title compounds were confirmed by IR,1H NMR and elemental analysis.The preliminary greenhouse biological activity tests showed that compounds 2b,2c,2e and 2h have a good activity in plant growth regulation.
Thirteen N-(1,3,4-thiodiazol-2-y1)-N'-aroyl ureas were synthesized by the reaction of aroyl iso-cyanates with 2-amino-1,3,4-thiodiazole in yields of 54.5%~86.2%.The structures of the title compounds were confirmed by IR,1H NMR and elemental analysis.The preliminary greenhouse biological activity tests showed that compounds 2b,2c,2e and 2h have a good activity in plant growth regulation.
2005, 22(3): 282-285
Abstract:
Gold nanoparticles were studied with resonance scattering spectroscopy and trans mission electron microscopy.When the concentration of gold nanparticles with d=10 nm is less than 35.4×10-6 g/mL,there are a max absorption peak at 525 nm and a resonance scattering peak at 525 nm.When the concentration of gold nanparticles with d=50 nm is less than 17.7×10-6 g/mL,there are a max absorption peak at 530 nm and a resonance scattering peak at 530 nm.When the concentration of gold nanoparticles is higher,there are red-shift of resonance scattering peak and resonance scattering quenching.On the basis of the interaction between the excited photon and the interface electron of nanoparticles,as well as the multi-scattering occured due to the interaction between photons and nanoparticles,the relationship between resonance scattering and resonance absorbance,the red-shift and quenching of resonance scattering peak were studied.
Gold nanoparticles were studied with resonance scattering spectroscopy and trans mission electron microscopy.When the concentration of gold nanparticles with d=10 nm is less than 35.4×10-6 g/mL,there are a max absorption peak at 525 nm and a resonance scattering peak at 525 nm.When the concentration of gold nanparticles with d=50 nm is less than 17.7×10-6 g/mL,there are a max absorption peak at 530 nm and a resonance scattering peak at 530 nm.When the concentration of gold nanoparticles is higher,there are red-shift of resonance scattering peak and resonance scattering quenching.On the basis of the interaction between the excited photon and the interface electron of nanoparticles,as well as the multi-scattering occured due to the interaction between photons and nanoparticles,the relationship between resonance scattering and resonance absorbance,the red-shift and quenching of resonance scattering peak were studied.
2005, 22(3): 286-290
Abstract:
1-Phenyl-3-methylthio (methanesulfonyl)-5-substituted aryl 6-(4-(2-alkoxy carbonyl) ethoxy) phenoxypyrazolo [3,4-d] pyrimidin-4-one derivatives (6 and 7) were synthesized by a tandem aza-Wittig and annulation reaction of iminophosphorance 4 with aromatic isocyanate and substituted phenols.The structures of all the target compounds have been confirmed.The preliminary bioassay tests indicate that compounds 6h,7a,7c possess high herbicidal activities against the roots of rape and barnyard grass.Their inhibitory rates against the roots of rape and barnyard grass are more than 90%.
1-Phenyl-3-methylthio (methanesulfonyl)-5-substituted aryl 6-(4-(2-alkoxy carbonyl) ethoxy) phenoxypyrazolo [3,4-d] pyrimidin-4-one derivatives (6 and 7) were synthesized by a tandem aza-Wittig and annulation reaction of iminophosphorance 4 with aromatic isocyanate and substituted phenols.The structures of all the target compounds have been confirmed.The preliminary bioassay tests indicate that compounds 6h,7a,7c possess high herbicidal activities against the roots of rape and barnyard grass.Their inhibitory rates against the roots of rape and barnyard grass are more than 90%.
2005, 22(3): 291-294
Abstract:
r-Methacryloxypropyl nano-sized silica (MPNS) was copolymerized with maleic anhydride (MA) in toluene when BPO was used as initiator.The structure and property of MPNS/PMA nanocomposite were characterized by FT-IR,TEM and TGA.The results show that the addition of nano-sized SiO2 improved the thermal stability of PMA.When MPNS/PMA nanocomposite was used for the pretanning and retanning of sheep skin,the shrinkage temperature of the pickled and blue sheep skin were increased by 15.5 and 11℃ respectively,with the thickness of crust leather increasing 70% and 48%.
r-Methacryloxypropyl nano-sized silica (MPNS) was copolymerized with maleic anhydride (MA) in toluene when BPO was used as initiator.The structure and property of MPNS/PMA nanocomposite were characterized by FT-IR,TEM and TGA.The results show that the addition of nano-sized SiO2 improved the thermal stability of PMA.When MPNS/PMA nanocomposite was used for the pretanning and retanning of sheep skin,the shrinkage temperature of the pickled and blue sheep skin were increased by 15.5 and 11℃ respectively,with the thickness of crust leather increasing 70% and 48%.
2005, 22(3): 295-299
Abstract:
The electrochemical behavior of horse-heart cytochrome c(Cytc) adsorbed on L-cys/Au electrode surface was investigated by means of cyclic voltammetry,ac impedance and ultraviolet spectrometric measurements.The average adsorbance of Cytochrome c on the membrane electrode surface is 1.366×10-10 mol/cm2.Cytc immobilized on L-Cys/Au SAMs by electrostatic interaction maintains biological activity and electrochemical activity.The voltammetric peak current is in linear relation with the potential sweep rate at a low scan rate.Cyt showed a surface-controlled electrode process.The standard heterogeneous electron transfer rate constant calculated via ac impedence spectrum is 7.529×10-4 cm/s.The adsorbed Cytc could electrocatalyze the reduction of hydrogen peroxide.The relationship between the catalytic current and H2O2 concentration exhibits a Michaelis-Menten kinetic mechanism for the electrocatalytic process and the constant Kmapp value was found to be 1.21×10-3 mol/L.The cytochrome c adsorbed on L-Cys/Au SAMs exhibits a comparably high affinity for H2O2.
The electrochemical behavior of horse-heart cytochrome c(Cytc) adsorbed on L-cys/Au electrode surface was investigated by means of cyclic voltammetry,ac impedance and ultraviolet spectrometric measurements.The average adsorbance of Cytochrome c on the membrane electrode surface is 1.366×10-10 mol/cm2.Cytc immobilized on L-Cys/Au SAMs by electrostatic interaction maintains biological activity and electrochemical activity.The voltammetric peak current is in linear relation with the potential sweep rate at a low scan rate.Cyt showed a surface-controlled electrode process.The standard heterogeneous electron transfer rate constant calculated via ac impedence spectrum is 7.529×10-4 cm/s.The adsorbed Cytc could electrocatalyze the reduction of hydrogen peroxide.The relationship between the catalytic current and H2O2 concentration exhibits a Michaelis-Menten kinetic mechanism for the electrocatalytic process and the constant Kmapp value was found to be 1.21×10-3 mol/L.The cytochrome c adsorbed on L-Cys/Au SAMs exhibits a comparably high affinity for H2O2.
2005, 22(3): 300-303
Abstract:
ZnGa2O4 phosphors were synthesized from ZnO and GaO(OH) by high temperature reaction in solid state.The product was characterized by means of XRD and the emission spectrometric analysis.The results show that the pure phase of ZnGa2O4 was obtained when the molar ratio of ZnO to GaO(OH) was 1.2:2.The sample with n(GaO(OH)):n(ZnO)=2.0:0.9 (mole ratio) exhibits the strongest fluorescence intensity.Moreover,the product synthesized from GaO(OH) and ZnO has better property than those synthesized from ZnO with α-Ga2O3 or β-Ga2O3.
ZnGa2O4 phosphors were synthesized from ZnO and GaO(OH) by high temperature reaction in solid state.The product was characterized by means of XRD and the emission spectrometric analysis.The results show that the pure phase of ZnGa2O4 was obtained when the molar ratio of ZnO to GaO(OH) was 1.2:2.The sample with n(GaO(OH)):n(ZnO)=2.0:0.9 (mole ratio) exhibits the strongest fluorescence intensity.Moreover,the product synthesized from GaO(OH) and ZnO has better property than those synthesized from ZnO with α-Ga2O3 or β-Ga2O3.
2005, 22(3): 304-307
Abstract:
The title cathode material for lithium ion battery was prepared by the sol-gel method and investigated by means of physical and electrochemical methods as the function of preparation conditions.Its structure and electrical behavior were characterized and measured by virtue of XRD technique,DSC,cyclic valtommetry and constant-current charging-discharging tests.The results show that LiNi0.45Co0.1Mn0.45O2 obtained from calcination at 700℃ for 7 h exhibited a specific discharging capacity up to 145 mA·h/g after 30 charging-discharging cycles at 3.0~4.3 V.
The title cathode material for lithium ion battery was prepared by the sol-gel method and investigated by means of physical and electrochemical methods as the function of preparation conditions.Its structure and electrical behavior were characterized and measured by virtue of XRD technique,DSC,cyclic valtommetry and constant-current charging-discharging tests.The results show that LiNi0.45Co0.1Mn0.45O2 obtained from calcination at 700℃ for 7 h exhibited a specific discharging capacity up to 145 mA·h/g after 30 charging-discharging cycles at 3.0~4.3 V.
2005, 22(3): 308-311
Abstract:
A novel photochromic compound,5-(quinolin-8-yloxy)-6,11-naphthacenediquinone (compound 2) was synthesized by reacting 5-chloro-6,11-naph thacenediquinone with 8-hydroxyquinoline in dry DMSO in the presence of potassium carbonate.Like phenoxynaphthacenequinone,the compound shows similar photo-chromic property in benzene,chloroform and DMSO.It exhibits a characteristic double-peak at about 450 nm and 480 nm with an isobestic point at about 400 nm under irradiation of UV light at 365 nm.It was also observed that the position of the longwave absorption bands for compound 2 only slightly depends on the nature of the solvent used.
A novel photochromic compound,5-(quinolin-8-yloxy)-6,11-naphthacenediquinone (compound 2) was synthesized by reacting 5-chloro-6,11-naph thacenediquinone with 8-hydroxyquinoline in dry DMSO in the presence of potassium carbonate.Like phenoxynaphthacenequinone,the compound shows similar photo-chromic property in benzene,chloroform and DMSO.It exhibits a characteristic double-peak at about 450 nm and 480 nm with an isobestic point at about 400 nm under irradiation of UV light at 365 nm.It was also observed that the position of the longwave absorption bands for compound 2 only slightly depends on the nature of the solvent used.
2005, 22(3): 312-315
Abstract:
The chelation reactions of chitosan to Ag(Ⅰ) ions and chitosan membrane to Ag(Ⅰ) ions as template (CMAT) to Ag(Ⅰ) ions were studied comparatively.Their adsorption isothermal kinetic equations,lnc=k't were obtained via dc/dt=-kcn linear correlation at 30~70℃.The apparent activati on energy of chitosan chelating to Ag(Ⅰ) ions and CMAT coordinating to Ag(Ⅰ) ions are 88.4 kJ/mol and 47.1 kJ/mol respectively.The chelating properties of CMAT to mixed ions (Pb(Ⅱ),Cu(Ⅱ),Ag(Ⅱ)) were also studied,and the experiment results show that CMAT has better selectivity and "memory" for Ag(Ⅰ).The chelation mechanism was studied by means of infrared spectrometry (IR) and X-ray photoelectron spectroscopy (XPS),the results indicate that the coordinating atom is not the O atom of the -OH but the N atom of the -NH2 of chitosan.
The chelation reactions of chitosan to Ag(Ⅰ) ions and chitosan membrane to Ag(Ⅰ) ions as template (CMAT) to Ag(Ⅰ) ions were studied comparatively.Their adsorption isothermal kinetic equations,lnc=k't were obtained via dc/dt=-kcn linear correlation at 30~70℃.The apparent activati on energy of chitosan chelating to Ag(Ⅰ) ions and CMAT coordinating to Ag(Ⅰ) ions are 88.4 kJ/mol and 47.1 kJ/mol respectively.The chelating properties of CMAT to mixed ions (Pb(Ⅱ),Cu(Ⅱ),Ag(Ⅱ)) were also studied,and the experiment results show that CMAT has better selectivity and "memory" for Ag(Ⅰ).The chelation mechanism was studied by means of infrared spectrometry (IR) and X-ray photoelectron spectroscopy (XPS),the results indicate that the coordinating atom is not the O atom of the -OH but the N atom of the -NH2 of chitosan.
2005, 22(3): 316-319
Abstract:
Seven s-triazolo[3,4-b]-1,3,4-thiadiazole derivatives containing coumarin and furan were synthesized in yields of 57%~70% via the condensation of thiocarbohydrazide 1,3-substituted-4-amino-5-mercapto-1,2,4-triazoles 2 and 5 with various heterocyclic carboxylic acids in the presence of phosphorus oxychloride.The compounds obtained were characteriz ed by elemental analysis,IR,1H NMR and MS.
Seven s-triazolo[3,4-b]-1,3,4-thiadiazole derivatives containing coumarin and furan were synthesized in yields of 57%~70% via the condensation of thiocarbohydrazide 1,3-substituted-4-amino-5-mercapto-1,2,4-triazoles 2 and 5 with various heterocyclic carboxylic acids in the presence of phosphorus oxychloride.The compounds obtained were characteriz ed by elemental analysis,IR,1H NMR and MS.
2005, 22(3): 320-325
Abstract:
The co-precipitation method was employed to prepare barium and lanthanum he xaaluminate catalysts AMnxAl12-xO19(A=La or Ba)(x=0.5,1,2,3) for methane combustion.The influences of La3+ and Ba2+ as mirror plane cations on the structure and thermal stability of hexaa luminates and the catalytic activity for methane combustion over them were investigated by means of XRD,BET,TPR techniques.The results show that the hexa aluminates possessed MP and β-Al2O3 structures when La3+ and Ba2+ were taken as mirror plane cations.Taking La3+ as mirror plane cation can avoid decreasing the surface area of the catalysts,enhance the structural stability of the catalysts,increase the oxidation state of active component Mn,the catalytic activity is thus improved.The catalysts po ssess optimal catalytic activity as x is equal to 2.
The co-precipitation method was employed to prepare barium and lanthanum he xaaluminate catalysts AMnxAl12-xO19(A=La or Ba)(x=0.5,1,2,3) for methane combustion.The influences of La3+ and Ba2+ as mirror plane cations on the structure and thermal stability of hexaa luminates and the catalytic activity for methane combustion over them were investigated by means of XRD,BET,TPR techniques.The results show that the hexa aluminates possessed MP and β-Al2O3 structures when La3+ and Ba2+ were taken as mirror plane cations.Taking La3+ as mirror plane cation can avoid decreasing the surface area of the catalysts,enhance the structural stability of the catalysts,increase the oxidation state of active component Mn,the catalytic activity is thus improved.The catalysts po ssess optimal catalytic activity as x is equal to 2.
2005, 22(3): 326-330
Abstract:
Thermal oxidation of hydrolytic collagen and the mechanism of CaSO4 format ion in the presence of both L-ascorbic acid and H2O2 have been investigated.The results show that the SO2 content in the protein is affected by L-ascorbic acid,H2O2,temperature and pH of the reaction system.In the presence of L-ascorbic acid and H2O2,free Met could be oxidized,giving SO2 within 4 min when temperature is above 65℃.At a ratio of V(hydrolytic collagen):V(H2O2):m(L-ascorbic acid)=100:5:1 and 75℃,the concentration of SO2 in hydrolytic collagen is decreased from 5.13×10-3 g/mL to 0.1×10-3 g/mL within 20 min,and is then increased to 3.46×10-3 g/mL at 60 min.Thus,the mechanism of CaSO4 formati on could be considered as follows.Under acid condition,H2O2 at first reacts with L-ascorbic acid,giving peroxy ascorbic acid,the latter then oxidizes HSO-3,-S-S-and CH3-S-in the hydrolytic collagen,giving SO42- at last,resulting to the formation of CaSO4 precipitate if there is Ca2+ in the system.
Thermal oxidation of hydrolytic collagen and the mechanism of CaSO4 format ion in the presence of both L-ascorbic acid and H2O2 have been investigated.The results show that the SO2 content in the protein is affected by L-ascorbic acid,H2O2,temperature and pH of the reaction system.In the presence of L-ascorbic acid and H2O2,free Met could be oxidized,giving SO2 within 4 min when temperature is above 65℃.At a ratio of V(hydrolytic collagen):V(H2O2):m(L-ascorbic acid)=100:5:1 and 75℃,the concentration of SO2 in hydrolytic collagen is decreased from 5.13×10-3 g/mL to 0.1×10-3 g/mL within 20 min,and is then increased to 3.46×10-3 g/mL at 60 min.Thus,the mechanism of CaSO4 formati on could be considered as follows.Under acid condition,H2O2 at first reacts with L-ascorbic acid,giving peroxy ascorbic acid,the latter then oxidizes HSO-3,-S-S-and CH3-S-in the hydrolytic collagen,giving SO42- at last,resulting to the formation of CaSO4 precipitate if there is Ca2+ in the system.
2005, 22(3): 331-333
Abstract:
Supported loaded semiconductors (MoO3,ZnO)-TiO2/SiO2 were prepared by an isovolumetric impregnation method from TiO2/SiO2 prepared by chemical modification reaction.The chemisorption property and photon a bsorption ability of MoO3-TiO2/SiO2 and ZnO-TiO2/SiO2 were investigated by BET,UV-Vis DRS,IR and TPD-MS techniques.The gas-phase photocatalytic reaction of CH4 with H2O was performed at 150℃ in a fixed-bed annular reactor.The results show that the conversion of methane and the selectivity of methanol reach to 5.1% and 87.3% respectively over MoO3-TiO2/SiO2,and MoO3-TiO2/SiO2 exhibits higher photocatalytic acivity than ZnO-TiO2/SiO2.
Supported loaded semiconductors (MoO3,ZnO)-TiO2/SiO2 were prepared by an isovolumetric impregnation method from TiO2/SiO2 prepared by chemical modification reaction.The chemisorption property and photon a bsorption ability of MoO3-TiO2/SiO2 and ZnO-TiO2/SiO2 were investigated by BET,UV-Vis DRS,IR and TPD-MS techniques.The gas-phase photocatalytic reaction of CH4 with H2O was performed at 150℃ in a fixed-bed annular reactor.The results show that the conversion of methane and the selectivity of methanol reach to 5.1% and 87.3% respectively over MoO3-TiO2/SiO2,and MoO3-TiO2/SiO2 exhibits higher photocatalytic acivity than ZnO-TiO2/SiO2.
2005, 22(3): 334-336
Abstract:
Ten novel Schiff bases of 2-amino-5-(4-pyridyl)-1,3,4-thiodiazole have been synthesized in the yields of 46.9%~65.8%.The structures of the compounds were confirmed by means of UV,IR,1H NMR and elemental analysis.The preliminary room bioactivity tests showed that Schiff bases from chlorobenzaldehyde and dichlorobenzaldehyde have a good plant growth regulation activity,where Ⅱc,Ⅱe and Ⅱg have excellent activities while auxin,Ⅱd and Ⅱi have better activities towards cytokinin.
Ten novel Schiff bases of 2-amino-5-(4-pyridyl)-1,3,4-thiodiazole have been synthesized in the yields of 46.9%~65.8%.The structures of the compounds were confirmed by means of UV,IR,1H NMR and elemental analysis.The preliminary room bioactivity tests showed that Schiff bases from chlorobenzaldehyde and dichlorobenzaldehyde have a good plant growth regulation activity,where Ⅱc,Ⅱe and Ⅱg have excellent activities while auxin,Ⅱd and Ⅱi have better activities towards cytokinin.
2005, 22(3): 337-339
Abstract:
Poly (acrylic acid)/nylon1313 and polystyrene/nylon1313 blends were prepared using supercritical CO2 as both the substrate-swelling agent and the monomer/initiator carrier.The desorption of CO2 from CO2-saturated nylon1313 is linearly dependent on the logarithm of time.Both IR and SEM data show the existence of the PAA or the PS phases within the nylon1313 matrix in the blends.Compared to nylon1313,the heat of fusion of CO2-plasticized nylon1313 is greater,and that of the CO2-plasticized PAA/nylon1313 and PS/nylon1313 blends are smaller.
Poly (acrylic acid)/nylon1313 and polystyrene/nylon1313 blends were prepared using supercritical CO2 as both the substrate-swelling agent and the monomer/initiator carrier.The desorption of CO2 from CO2-saturated nylon1313 is linearly dependent on the logarithm of time.Both IR and SEM data show the existence of the PAA or the PS phases within the nylon1313 matrix in the blends.Compared to nylon1313,the heat of fusion of CO2-plasticized nylon1313 is greater,and that of the CO2-plasticized PAA/nylon1313 and PS/nylon1313 blends are smaller.
2005, 22(3): 340-342
Abstract:
Seven derivatives of 1,3-dithiocyclohexane were prepared via the reaction of 7 aldehydes (or ketones) with Bunte's salt prepared from 1,3-dichloropropane and sodium thiosulfate.The procedure has the feature of easier operation,shorter reaction time and higher yield.The yields of seven derivatives of 1,3-dithiocyclohexane are between 58% and 75%.The optimum molar ratio of 1,3-dichloropropane to sodium thiosulfate was 1:1 in the preparati on of Bunte's salt.The structures of seven derivatives were characterized by means of IR,1H NMR,MS.
Seven derivatives of 1,3-dithiocyclohexane were prepared via the reaction of 7 aldehydes (or ketones) with Bunte's salt prepared from 1,3-dichloropropane and sodium thiosulfate.The procedure has the feature of easier operation,shorter reaction time and higher yield.The yields of seven derivatives of 1,3-dithiocyclohexane are between 58% and 75%.The optimum molar ratio of 1,3-dichloropropane to sodium thiosulfate was 1:1 in the preparati on of Bunte's salt.The structures of seven derivatives were characterized by means of IR,1H NMR,MS.
2005, 22(3): 343-345
Abstract:
2-Aryl-3,5,5-trimethyl-2-morpholinols were synthesized from the reactions of 2-methyl-2-aminopropanol with 2-bromopropiophenone,2-bromo-3'-chlorop ropiophenone,2-bromo-4'-benzyloxypropio-phenone or 6-methoxy-2-(2-bromopropionyl) naphthalene for 1 h in N-methylpyrrolidone at 35℃.The 2-aryl-3,5,5-trimethyl-2-morpholinols were then reacted with hydrochlo ride in Et2O to give the corresponding hydrochloride salts with yields of 84.9% 86.4%,respectively.The structures of 2-aryl-3,5,5-trimethyl-2-morpholinol hydrochlorides were confirmed by mean of IR,1H NMR,MS spectral data.
2-Aryl-3,5,5-trimethyl-2-morpholinols were synthesized from the reactions of 2-methyl-2-aminopropanol with 2-bromopropiophenone,2-bromo-3'-chlorop ropiophenone,2-bromo-4'-benzyloxypropio-phenone or 6-methoxy-2-(2-bromopropionyl) naphthalene for 1 h in N-methylpyrrolidone at 35℃.The 2-aryl-3,5,5-trimethyl-2-morpholinols were then reacted with hydrochlo ride in Et2O to give the corresponding hydrochloride salts with yields of 84.9% 86.4%,respectively.The structures of 2-aryl-3,5,5-trimethyl-2-morpholinol hydrochlorides were confirmed by mean of IR,1H NMR,MS spectral data.
2005, 22(3): 346-348
Abstract:
Poly (lactic acid)/montmorillonite nanocomposites were prepared by the melt intercalation method.Their structures and thermal properties were investigated by WAXD,DSC and TGA techniques.The WAXD results show that the interlayer spacing of montmorillonite in the nanocomposites was increased after melt intercalation,indicating that the molecular chains of poly (lactic acid) had been intercalated into the montmo-rillonite layers.The thermal stability of poly (lactic acid) was obviously improved after intercalation with montmorillonite.Compared with that of pure poly (lactic acid),the thermal decomposition temperatures of the nanocomposites were increased by about 22.5℃ in air and 14℃ in N2,respectively.
Poly (lactic acid)/montmorillonite nanocomposites were prepared by the melt intercalation method.Their structures and thermal properties were investigated by WAXD,DSC and TGA techniques.The WAXD results show that the interlayer spacing of montmorillonite in the nanocomposites was increased after melt intercalation,indicating that the molecular chains of poly (lactic acid) had been intercalated into the montmo-rillonite layers.The thermal stability of poly (lactic acid) was obviously improved after intercalation with montmorillonite.Compared with that of pure poly (lactic acid),the thermal decomposition temperatures of the nanocomposites were increased by about 22.5℃ in air and 14℃ in N2,respectively.
