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2002 Volume 19 Issue 12
2002, 19(12): 1123-1127
Abstract:
Zirconia and zirconia-ceria microspheres were synthesized as stationary phases for HPLC by a sol-gel process. The chromatographic behavior of inorganic anions and benzoic acid derivatives was systematically investigated. Zirconia and zirconia-ceria exhibit anion-exchange property only in the pH value below their zero change points. The elution order of five inorganic anions are I-, Br-, NO3-, NO2-, NO3-. Benzoic acid derivatives showed a more retention value on zirconia and zirconia-ceria mainly by ligand-exchange interaction, and the retention values were attenuated by the addition of a competing Lewis bases to the mobile phase. Moderate retention of benzoic acid derivatives on zirconia and zirconia-ceria can be obtained by using acetate buffer as a mobile phase.
Zirconia and zirconia-ceria microspheres were synthesized as stationary phases for HPLC by a sol-gel process. The chromatographic behavior of inorganic anions and benzoic acid derivatives was systematically investigated. Zirconia and zirconia-ceria exhibit anion-exchange property only in the pH value below their zero change points. The elution order of five inorganic anions are I-, Br-, NO3-, NO2-, NO3-. Benzoic acid derivatives showed a more retention value on zirconia and zirconia-ceria mainly by ligand-exchange interaction, and the retention values were attenuated by the addition of a competing Lewis bases to the mobile phase. Moderate retention of benzoic acid derivatives on zirconia and zirconia-ceria can be obtained by using acetate buffer as a mobile phase.
2002, 19(12): 1128-1132
Abstract:
Seventeen benzopyran-4-urea, -thiourea and -cyanogunidine derivatives were synthesized as K+ channel openers. Their structures were confirmed by IR, 1H NMR, MS and elemental analysis. Their vasorelaxant activities againat low (30 mmol/L) KCl-induced contraction were preliminary evaluated on rat aorta in vitro. Some compounds synthesized(7c, 8a, 8b and 8c) were found exhibited some, but less, low concentration K+(30 mmol/L KCl) channel opening activity than Emakalim.
Seventeen benzopyran-4-urea, -thiourea and -cyanogunidine derivatives were synthesized as K+ channel openers. Their structures were confirmed by IR, 1H NMR, MS and elemental analysis. Their vasorelaxant activities againat low (30 mmol/L) KCl-induced contraction were preliminary evaluated on rat aorta in vitro. Some compounds synthesized(7c, 8a, 8b and 8c) were found exhibited some, but less, low concentration K+(30 mmol/L KCl) channel opening activity than Emakalim.
2002, 19(12): 1133-1136
Abstract:
A maximum absorption peak at 520 nm and a fluorescence peak at 550 nm were observed for rhodamine 6G(RDG) in 0.2 mol/L HCl. In the presence of KI and Au(Ⅲ), the AuI4- and RDG+ combine into hydrophobic AuI4-RDG association molecule through electric attraction. The strong Van der Waals force and hydrophobic forces among AuI4-RDG molecules lead to the formation of ((AuI4)-RDG)n association nanoparticles in red-violet color which exhibit a characteristic resonance scattering peaks at 600 nm and fluorescence quenching at 550 nm. The ((AuI4)RDG)n nanoparticles could be decomposed into individual (AuI4)RDG association molecule by alcohol and the resonance scattering peaks and the red-violet color disappeared, whereas the A520 nm and F470 nm/550 nm occurred again. The results demonstrate that the formation of ((AuI4)RDG)n composite nanoparticle in red-violet and the interface between the nanoparticle solid phase and water phase give rise to its enhanced resonance scattering,fluorescence quenching, hypochromic effect with a characteristic resonance scattering peaks at 600 nm.
A maximum absorption peak at 520 nm and a fluorescence peak at 550 nm were observed for rhodamine 6G(RDG) in 0.2 mol/L HCl. In the presence of KI and Au(Ⅲ), the AuI4- and RDG+ combine into hydrophobic AuI4-RDG association molecule through electric attraction. The strong Van der Waals force and hydrophobic forces among AuI4-RDG molecules lead to the formation of ((AuI4)-RDG)n association nanoparticles in red-violet color which exhibit a characteristic resonance scattering peaks at 600 nm and fluorescence quenching at 550 nm. The ((AuI4)RDG)n nanoparticles could be decomposed into individual (AuI4)RDG association molecule by alcohol and the resonance scattering peaks and the red-violet color disappeared, whereas the A520 nm and F470 nm/550 nm occurred again. The results demonstrate that the formation of ((AuI4)RDG)n composite nanoparticle in red-violet and the interface between the nanoparticle solid phase and water phase give rise to its enhanced resonance scattering,fluorescence quenching, hypochromic effect with a characteristic resonance scattering peaks at 600 nm.
2002, 19(12): 1137-1141
Abstract:
The ultrafine molecular sieve Ti-MCM-41 with molar ratios of Si to Ti being 30, 50 and 70 respectively were prepared from a 0.36 mol/L HCl solution at 40℃ and normal pressure. The molecular sieves were proved to have a regular skeleton structure with diameters ranged in 0.05 to 0.1 μm as determined by XRD, FTIR and SEM techniques. The catalytic activity of the molecular sieves Ti-MCM-41 in the oxidation of styrene by hydrogen peroxide was examined. The results showed that the styrene conversion was improved by increasing the titanium content, adding the promoter such as LiCl, K2SO4 and NaNO3, using methanol as a solvent as well as extending the reaction time and raising the reaction temperature.
The ultrafine molecular sieve Ti-MCM-41 with molar ratios of Si to Ti being 30, 50 and 70 respectively were prepared from a 0.36 mol/L HCl solution at 40℃ and normal pressure. The molecular sieves were proved to have a regular skeleton structure with diameters ranged in 0.05 to 0.1 μm as determined by XRD, FTIR and SEM techniques. The catalytic activity of the molecular sieves Ti-MCM-41 in the oxidation of styrene by hydrogen peroxide was examined. The results showed that the styrene conversion was improved by increasing the titanium content, adding the promoter such as LiCl, K2SO4 and NaNO3, using methanol as a solvent as well as extending the reaction time and raising the reaction temperature.
2002, 19(12): 1142-1145
Abstract:
The reactions of diferrocenylmethanol, ferrocenyl-2,1'-diethylferrocenylmethanol and ferrocenyl-3,1'-diethylferrocenylmethanol with BF3 in CH2Cl2 produced the stable diferrocenylmethyl carbocations. Without separation from the reaction mixture, the cations were treated with aminoethyl alcohol to afford three diferrocenylmethylaminoethyl alcohols respectively. The silylation of the aminoalcohols with trimethylchlorosilane in the presence of triethylamine gave directly the corresponding alkoxysilanes. All of the compounds synthesized were characterized by IR, 1H NMR spectra and elemental analysis.
The reactions of diferrocenylmethanol, ferrocenyl-2,1'-diethylferrocenylmethanol and ferrocenyl-3,1'-diethylferrocenylmethanol with BF3 in CH2Cl2 produced the stable diferrocenylmethyl carbocations. Without separation from the reaction mixture, the cations were treated with aminoethyl alcohol to afford three diferrocenylmethylaminoethyl alcohols respectively. The silylation of the aminoalcohols with trimethylchlorosilane in the presence of triethylamine gave directly the corresponding alkoxysilanes. All of the compounds synthesized were characterized by IR, 1H NMR spectra and elemental analysis.
2002, 19(12): 1146-1149
Abstract:
Holmium doped polystyrene(Ho(i-C4)/PS) was prepared by bulk polymerization of the mixture of styrene with tri-isobutoxide holmium and characterized by FT-IR, XPS, DTA-TG and DMTA as well as impact strength measurement. The results showed that coordination interaction exits in the doped PS between Ho and c electron of benzene ring. The thermal stability and the impact strength was significantly improved with increasing k(Ho), the highest impact strength value was obtained as the k(Ho) was 5.0% in the doped products. The toughening mechanism of the doped PS has been discussed based on the results from DMTA and SEM.
Holmium doped polystyrene(Ho(i-C4)/PS) was prepared by bulk polymerization of the mixture of styrene with tri-isobutoxide holmium and characterized by FT-IR, XPS, DTA-TG and DMTA as well as impact strength measurement. The results showed that coordination interaction exits in the doped PS between Ho and c electron of benzene ring. The thermal stability and the impact strength was significantly improved with increasing k(Ho), the highest impact strength value was obtained as the k(Ho) was 5.0% in the doped products. The toughening mechanism of the doped PS has been discussed based on the results from DMTA and SEM.
2002, 19(12): 1150-1153
Abstract:
The diameters of gold nanoparticles in dark-red, purple and blue-violet colors were 8.3, 30 and 60 nm, respectively. The maximum peak in UV absorption spectra was at 524 nm and 542 nm for dark-red and purple gold particles, respectively, while their maximum peaks in resonance scattering spectra were at 570 nm and 550 nm, respectively. Two absorption peaks were observed:530 nm and 620 nm for blue-violet gold nanoparticles, whose maximum resonance scattering peak was found at 550 nm. A solution of dark-red gold nanoparticles with diameter of 8.3 nm in concentration of [Au]<5.0×10-4 g/L could be obtained from a solution of PAAm and Au(Ⅲ) at m(PAAm)/m(Au(Ⅲ))=19. The procedure has advantages of rapidity and convenience and can efford red gold nanoparticles with uniform distribution and good stability.
The diameters of gold nanoparticles in dark-red, purple and blue-violet colors were 8.3, 30 and 60 nm, respectively. The maximum peak in UV absorption spectra was at 524 nm and 542 nm for dark-red and purple gold particles, respectively, while their maximum peaks in resonance scattering spectra were at 570 nm and 550 nm, respectively. Two absorption peaks were observed:530 nm and 620 nm for blue-violet gold nanoparticles, whose maximum resonance scattering peak was found at 550 nm. A solution of dark-red gold nanoparticles with diameter of 8.3 nm in concentration of [Au]<5.0×10-4 g/L could be obtained from a solution of PAAm and Au(Ⅲ) at m(PAAm)/m(Au(Ⅲ))=19. The procedure has advantages of rapidity and convenience and can efford red gold nanoparticles with uniform distribution and good stability.
2002, 19(12): 1154-1157
Abstract:
Water-soluble phosphine ligands Na2O3PCH2CH2N(CH2PPh2)[CH2CH2N(CH2PPh2)]n-CH2CH2OH(n=0,1) containing diphenylphosphine complexing group were synthesized by reaction of the 2-aminoethylphosphonic acid derivatives containing hydroxyl group with [Ph2P(CH2OH)2]+Cl- at 80~85℃, without necessity for any special reagents. The ligands were characterized by NMR, MS, IR and UV. Their distribution coefficients D in water/organic phase system were quantitatively determined by ultraviolet spectroscopy.
Water-soluble phosphine ligands Na2O3PCH2CH2N(CH2PPh2)[CH2CH2N(CH2PPh2)]n-CH2CH2OH(n=0,1) containing diphenylphosphine complexing group were synthesized by reaction of the 2-aminoethylphosphonic acid derivatives containing hydroxyl group with [Ph2P(CH2OH)2]+Cl- at 80~85℃, without necessity for any special reagents. The ligands were characterized by NMR, MS, IR and UV. Their distribution coefficients D in water/organic phase system were quantitatively determined by ultraviolet spectroscopy.
2002, 19(12): 1158-1161
Abstract:
Two novel heterotrinuclear complexes [Cu(oxca)]2M(H2O)2 where oxca denotes N-(2-carboxy phenyl)-N'-(3-aminopropyl) oxamide and M=Co2+, Ni2+ have been synthesized. The results of IR, elemental analysis, conductivity measurements, electronic spectra and thermogravimetry analysis indicate that the complexes have an extended oxamido-bridged structure. The variable-temperature magnetic susceptibility measurements of {[Cu(oxca)]2Co(H2O)2} over the range 4~300 K gave the exchange integral J=-28.09 cm-1.
Two novel heterotrinuclear complexes [Cu(oxca)]2M(H2O)2 where oxca denotes N-(2-carboxy phenyl)-N'-(3-aminopropyl) oxamide and M=Co2+, Ni2+ have been synthesized. The results of IR, elemental analysis, conductivity measurements, electronic spectra and thermogravimetry analysis indicate that the complexes have an extended oxamido-bridged structure. The variable-temperature magnetic susceptibility measurements of {[Cu(oxca)]2Co(H2O)2} over the range 4~300 K gave the exchange integral J=-28.09 cm-1.
2002, 19(12): 1162-1165
Abstract:
The properties of cis-1,4-polybutadiene rubber obtained with neodymium caprate catalysts in enlarged scale are reported. The results showed that modifying agent not only affects the macro molecular chain structure, reduces molecular weight and molecular weight distribution(MWD) of the raw rubber, but also the properties of the vulcanizate therefrom. The vulcanizate has tensile strength of about 15 MPa, but good abrasion resistance, heat build-up and wet skid resistance as well as lower rolling resistance.
The properties of cis-1,4-polybutadiene rubber obtained with neodymium caprate catalysts in enlarged scale are reported. The results showed that modifying agent not only affects the macro molecular chain structure, reduces molecular weight and molecular weight distribution(MWD) of the raw rubber, but also the properties of the vulcanizate therefrom. The vulcanizate has tensile strength of about 15 MPa, but good abrasion resistance, heat build-up and wet skid resistance as well as lower rolling resistance.
2002, 19(12): 1166-1169
Abstract:
Nanocrystalline Pb(Zr0.52Ti0.48)O3 was prepared from lead acetate, zirconium oxynitrate and tetrabutyltitanate by a sol-gel method. It is found that both the crystallization temperature of precursor PZT and PZT product size were increased with increase of V(C3H8O2)/V(H2O) ratio in solution used. At V(C3H8O2)/V(H2O)=4.47 the gel was formed moderately quick, and the nanocrystalline PZT with uniform granularity and low crystallization temperature could be obtained. The diameter of the final nanocrystalline was ranged in 60~70 nm as measured by atomic force microscopy(AFM). The crystallization temperature of the precursor PZT was 443℃ and the crystallization reaction was completed at 500℃ by DTA and TG. The sol-gel reaction process was monitored by FT-IR and XRD.
Nanocrystalline Pb(Zr0.52Ti0.48)O3 was prepared from lead acetate, zirconium oxynitrate and tetrabutyltitanate by a sol-gel method. It is found that both the crystallization temperature of precursor PZT and PZT product size were increased with increase of V(C3H8O2)/V(H2O) ratio in solution used. At V(C3H8O2)/V(H2O)=4.47 the gel was formed moderately quick, and the nanocrystalline PZT with uniform granularity and low crystallization temperature could be obtained. The diameter of the final nanocrystalline was ranged in 60~70 nm as measured by atomic force microscopy(AFM). The crystallization temperature of the precursor PZT was 443℃ and the crystallization reaction was completed at 500℃ by DTA and TG. The sol-gel reaction process was monitored by FT-IR and XRD.
2002, 19(12): 1170-1173
Abstract:
The mechanism of removing oil from wastewater by dithiocarbamate was studied and the effect of pH value of wastewater on the oil removing was discussed based on the floculation occurred in the course of oil removing. The floc that removes oil efficiently appeared produced in situ by the reaction of dithiocarbamate with ferrous ions in wastewater. The oil removing efficiency differed greatly with the pH of wastewater. With pH value ranged in 4~8 the oil removing efficiency was above 90%, beyond this range the oil removing results worsen apparently.
The mechanism of removing oil from wastewater by dithiocarbamate was studied and the effect of pH value of wastewater on the oil removing was discussed based on the floculation occurred in the course of oil removing. The floc that removes oil efficiently appeared produced in situ by the reaction of dithiocarbamate with ferrous ions in wastewater. The oil removing efficiency differed greatly with the pH of wastewater. With pH value ranged in 4~8 the oil removing efficiency was above 90%, beyond this range the oil removing results worsen apparently.
2002, 19(12): 1174-1177
Abstract:
The 6,7-methylenedioxy-3-aza(thia)-1(2H,4H)acridone 3a~3b were synthesized by condensation reaction of 1-aza- or 1-thia-3,5-cyclohexadione with o-aminobenzaldehyde. The Friedlännder reaction of 3b with o-amino benzaldehyde derivatives gave quinoline-fusedaza-acridine 4a~4c. The Pfitzing reaction of 3b with isatin compounds formed carboxyl quinoline-fused aza-acridine 5a~5c. 3a reacted with m-substituted phenylhydrazine to gave indol-fused thia-acridine 7a~7b. From keto-ester 8 prepared by Claisen condensation of 3a with ethyl oxalate two pyroazol-fused thia-acridines 9a~9b were obtained by condensation with thiazolhydrazine. The compositions and structures of all new compounds were characterized by elemental analysis, IR and 1H NMR.
The 6,7-methylenedioxy-3-aza(thia)-1(2H,4H)acridone 3a~3b were synthesized by condensation reaction of 1-aza- or 1-thia-3,5-cyclohexadione with o-aminobenzaldehyde. The Friedlännder reaction of 3b with o-amino benzaldehyde derivatives gave quinoline-fusedaza-acridine 4a~4c. The Pfitzing reaction of 3b with isatin compounds formed carboxyl quinoline-fused aza-acridine 5a~5c. 3a reacted with m-substituted phenylhydrazine to gave indol-fused thia-acridine 7a~7b. From keto-ester 8 prepared by Claisen condensation of 3a with ethyl oxalate two pyroazol-fused thia-acridines 9a~9b were obtained by condensation with thiazolhydrazine. The compositions and structures of all new compounds were characterized by elemental analysis, IR and 1H NMR.
2002, 19(12): 1178-1182
Abstract:
Chitosan microspheres(CM) were prepared by cross-linking of glutaraldehyde with chitosan solution(mass fraction 10%), and coated with Fe3O4 to give magnetic chitosan microspheres(MCM). SEM, IR, atomic absorption spectrometry and UV results indicated that the size of the polymer particles became smaller (<1μm) and more uniformly distributed with decrease of the chitosan molecular weight. In vitro measurement showed the CM entrapped with Aspirin(CM-AS) released about 40% drug, while MCM-AS released 15% in period within one hour. The releasing times for 50% drug were 1.5 h and 5 h, respectively, for CM-AS and MCM-AS. Both MCM and MCM-AS showed strongly magnetic response and promizing applications as targeting drug releasing agent.
Chitosan microspheres(CM) were prepared by cross-linking of glutaraldehyde with chitosan solution(mass fraction 10%), and coated with Fe3O4 to give magnetic chitosan microspheres(MCM). SEM, IR, atomic absorption spectrometry and UV results indicated that the size of the polymer particles became smaller (<1μm) and more uniformly distributed with decrease of the chitosan molecular weight. In vitro measurement showed the CM entrapped with Aspirin(CM-AS) released about 40% drug, while MCM-AS released 15% in period within one hour. The releasing times for 50% drug were 1.5 h and 5 h, respectively, for CM-AS and MCM-AS. Both MCM and MCM-AS showed strongly magnetic response and promizing applications as targeting drug releasing agent.
2002, 19(12): 1183-1185
Abstract:
Five silver(Ⅰ) complexes with Schiff bases obtained from salicylaldehyde and five corresponding T-amino acids were synthesized. The complexes were characterized by elemental analysis, IR and 1H NMR measurements. Bioactivity tests showed that the complexes inhibited the cucumber mosaic virus. Among them the best effective was glycine salicylaldehyde Schiffbase Ag(Ⅰ), which gave the effective level up to 74.7% towards CMV in dosage of 400 mg/L(in case of phaseolus vulgarisl inoculation).
Five silver(Ⅰ) complexes with Schiff bases obtained from salicylaldehyde and five corresponding T-amino acids were synthesized. The complexes were characterized by elemental analysis, IR and 1H NMR measurements. Bioactivity tests showed that the complexes inhibited the cucumber mosaic virus. Among them the best effective was glycine salicylaldehyde Schiffbase Ag(Ⅰ), which gave the effective level up to 74.7% towards CMV in dosage of 400 mg/L(in case of phaseolus vulgarisl inoculation).
2002, 19(12): 1186-1188
Abstract:
Common zinc oxide and nano-zinc oxide were used to composite natural rubber separately. Their vulcanization profiles and TGA curves showed the composite of natural rubber with nano-znic oxide possessed higher effective crosslinking ratio, then, the improved thermal stability and mechanical properties.
Common zinc oxide and nano-zinc oxide were used to composite natural rubber separately. Their vulcanization profiles and TGA curves showed the composite of natural rubber with nano-znic oxide possessed higher effective crosslinking ratio, then, the improved thermal stability and mechanical properties.
2002, 19(12): 1189-1191
Abstract:
3U-Hydroxy-16T,17T,21-trimethyl-5-en-20-one was synthesized from 3T-acetoxypregna-5,16-dien-20-one and characterized by elemental analysis, 1H NMR, MS and IR. 16T,17T-Dimethyl steroid was formed by treatment of 3U-acetoxypregna-5,16-dien-20-one with methylmagnesium bromide, followed by reaction of the resulting 17(20)-enolate with methyl iodide. The main by-products were 3U-hydroxy-16T,17T-dimethyl-5-en-20-one. LHDMS([(CH3)3Si]2NLi) and LDA([(CH3)2CH]2NLi) were chosen as proper reagents for 21-position alkylation. The almost quantitative conversion of 16T,17T-dimethyl corticosteroid was achieved and the highest yield of the 16T,17T,21-trimethyl corticosteroid was 78%. The optimum reaction temperature was -20℃ for 16T,17T-dialkylation and was -50℃ for 21-position alkylation.
3U-Hydroxy-16T,17T,21-trimethyl-5-en-20-one was synthesized from 3T-acetoxypregna-5,16-dien-20-one and characterized by elemental analysis, 1H NMR, MS and IR. 16T,17T-Dimethyl steroid was formed by treatment of 3U-acetoxypregna-5,16-dien-20-one with methylmagnesium bromide, followed by reaction of the resulting 17(20)-enolate with methyl iodide. The main by-products were 3U-hydroxy-16T,17T-dimethyl-5-en-20-one. LHDMS([(CH3)3Si]2NLi) and LDA([(CH3)2CH]2NLi) were chosen as proper reagents for 21-position alkylation. The almost quantitative conversion of 16T,17T-dimethyl corticosteroid was achieved and the highest yield of the 16T,17T,21-trimethyl corticosteroid was 78%. The optimum reaction temperature was -20℃ for 16T,17T-dialkylation and was -50℃ for 21-position alkylation.
2002, 19(12): 1192-1193
Abstract:
Cellulose strong anion exchangers(CSAE) were prepared from cellulose of wheat-straw, sawdust, buckwheat husk and rice husk. Exchange capacity of the exchangers was 0.8~0.6 mmol/g. The static and dynamic absorption capacities for dye Direct Light Turquoise GL were 181~192 mg/g and 179~197 mg/g, respectively. Good results in decolorization of printing wastewater were obtained.
Cellulose strong anion exchangers(CSAE) were prepared from cellulose of wheat-straw, sawdust, buckwheat husk and rice husk. Exchange capacity of the exchangers was 0.8~0.6 mmol/g. The static and dynamic absorption capacities for dye Direct Light Turquoise GL were 181~192 mg/g and 179~197 mg/g, respectively. Good results in decolorization of printing wastewater were obtained.
2002, 19(12): 1194-1196
Abstract:
Chitosan in 10% acetic acid solution was absorbed on the surface of silica gel particle. Chitosan-silica gel composite carrier was obtained by neutralization of chitosan acetate absorbed on silica gel in 1 mol/L NaOH solution. Lipase was immobilized on this carrier by formaldehyde as cross-linker. The stability of immobilized lipase, such as stability against temperature, acidity and storage in phosphate buffer solution, was examined. In comparison with natural lipase, immobilized lipase showed an improved stability. 70% activity was found for immobilized lipase at 55℃, pH 7.5 and 37℃, pH 9.5, whereas for natural lipase it was 40%. Moreover, the immobilized lipase kept its activity by 96.6%, 81% and 41% in phosphate buffer solution(pH=7.5) at 37℃ in period of 10, 15 and 20 days, respectively, while for natural lipase the activity disappeared under the same condition only in 3 days.
Chitosan in 10% acetic acid solution was absorbed on the surface of silica gel particle. Chitosan-silica gel composite carrier was obtained by neutralization of chitosan acetate absorbed on silica gel in 1 mol/L NaOH solution. Lipase was immobilized on this carrier by formaldehyde as cross-linker. The stability of immobilized lipase, such as stability against temperature, acidity and storage in phosphate buffer solution, was examined. In comparison with natural lipase, immobilized lipase showed an improved stability. 70% activity was found for immobilized lipase at 55℃, pH 7.5 and 37℃, pH 9.5, whereas for natural lipase it was 40%. Moreover, the immobilized lipase kept its activity by 96.6%, 81% and 41% in phosphate buffer solution(pH=7.5) at 37℃ in period of 10, 15 and 20 days, respectively, while for natural lipase the activity disappeared under the same condition only in 3 days.
2002, 19(12): 1197-1199
Abstract:
Two d-f heterodinuclear cryptates Eu(Ⅲ)-M(Ⅱ)(M=Zn2+, Ni2+) were synthesized and characterized by elemental analysis, IR and ES-MS. The fluorescence properties of the cyptates in acetonitrile solution show that inclusion of Zn2+ in the mononuclear europium(Ⅲ) cryptate increases the energy transfer between cryptand and europium(Ⅲ) ion, while the inclusion of Ni2+ in the cavity quenches the fluorescence of Eu(Ⅲ) cryptate.
Two d-f heterodinuclear cryptates Eu(Ⅲ)-M(Ⅱ)(M=Zn2+, Ni2+) were synthesized and characterized by elemental analysis, IR and ES-MS. The fluorescence properties of the cyptates in acetonitrile solution show that inclusion of Zn2+ in the mononuclear europium(Ⅲ) cryptate increases the energy transfer between cryptand and europium(Ⅲ) ion, while the inclusion of Ni2+ in the cavity quenches the fluorescence of Eu(Ⅲ) cryptate.
2002, 19(12): 1200-1202
Abstract:
The hydrogenation of aromatic ring and nitrobenzene over the amorphous nickel boron alloy has been investigated. The amorphous structure of the catalyst make itself exhibited a high catalytic activity in the hydrogenation of 4-ethylbenzoic acid, 4-pentylphenol and nitrobenzene. In the case of 4-pentylphenol and 4-ethylbenzoic acid, the hydrogenation conversions were 95%, 67% respectively, at 160℃ and hydrogen pressure of 6.0 MPa, while for nitrobenzene, the conversion was 100% at the same temperature under 4.0 MPa H2.
The hydrogenation of aromatic ring and nitrobenzene over the amorphous nickel boron alloy has been investigated. The amorphous structure of the catalyst make itself exhibited a high catalytic activity in the hydrogenation of 4-ethylbenzoic acid, 4-pentylphenol and nitrobenzene. In the case of 4-pentylphenol and 4-ethylbenzoic acid, the hydrogenation conversions were 95%, 67% respectively, at 160℃ and hydrogen pressure of 6.0 MPa, while for nitrobenzene, the conversion was 100% at the same temperature under 4.0 MPa H2.
