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1998 Volume 15 Issue 3
1998, 15(3): 1-5
Abstract:
The sol-gel process, with its associated mild conditions, especially the low reaction temperature, becomes the most effective method to prepare inorganic-organic nanocomposite materials. In this paper, according to the materials' synthetic routes, the sol-gel approach is reviewed in five parts.
The sol-gel process, with its associated mild conditions, especially the low reaction temperature, becomes the most effective method to prepare inorganic-organic nanocomposite materials. In this paper, according to the materials' synthetic routes, the sol-gel approach is reviewed in five parts.
1998, 15(3): 6-9
Abstract:
The titanium substituted heteropolytungstosilicate K6SiW11TiO40°16H2O (SiW11Ti) was synthesized and characterized by elemental analysis, IR, UV-Vis and 183W NMR spectra. Its electrochemical behavior in aqueous solution has been discussed. Its reduction process involves an one electron reduction of Ti(Ⅳ) and a pair of two-electron reduction of W (Ⅵ). It shows a good catalytic activity on the reduction of NO2- in weak acid medium.
The titanium substituted heteropolytungstosilicate K6SiW11TiO40°16H2O (SiW11Ti) was synthesized and characterized by elemental analysis, IR, UV-Vis and 183W NMR spectra. Its electrochemical behavior in aqueous solution has been discussed. Its reduction process involves an one electron reduction of Ti(Ⅳ) and a pair of two-electron reduction of W (Ⅵ). It shows a good catalytic activity on the reduction of NO2- in weak acid medium.
1998, 15(3): 10-14
Abstract:
A series of polyoxypropylene-g-epoxy resins(epoxy-g-PO) were synthesized from epoxy resin(epoxy) and polyoxypropylene with molecular weights from 230 to 1550. The grafting efficiency for these epoxy-g-POs was around 0.96. The morphology of such epoxy-g-POs and their networks were examined by means of FTIR, DSC and TEM, respectively. Partial microphase separation was observed in graft networks containing longer side chains(Mw≥950), while the graft network having short grafts(Mw=230) exhibited a compatible system. The impact strengths of epoxy cured with less amount of epoxy-g-PO(5% to 10%, wt) were enhanced appreciably, while the tensile strength and the heat resistance for these graft networks remained nearly as those of epoxy network. All the physical properties of the graft epoxy networks could be well related to their morphologies.
A series of polyoxypropylene-g-epoxy resins(epoxy-g-PO) were synthesized from epoxy resin(epoxy) and polyoxypropylene with molecular weights from 230 to 1550. The grafting efficiency for these epoxy-g-POs was around 0.96. The morphology of such epoxy-g-POs and their networks were examined by means of FTIR, DSC and TEM, respectively. Partial microphase separation was observed in graft networks containing longer side chains(Mw≥950), while the graft network having short grafts(Mw=230) exhibited a compatible system. The impact strengths of epoxy cured with less amount of epoxy-g-PO(5% to 10%, wt) were enhanced appreciably, while the tensile strength and the heat resistance for these graft networks remained nearly as those of epoxy network. All the physical properties of the graft epoxy networks could be well related to their morphologies.
1998, 15(3): 15-18
Abstract:
Macromolecular ligands were prepared by the condensation polymerization of diethylenetriaminepentaacetic dianhydride with long chain L-lysine alkyl esters. The corresponding paramagnetic metal complexes were also prepared by the reaction of these ligands with GdCl3. The relaxivities of these metal complexes are higher than that of Gd(DTPA).
Macromolecular ligands were prepared by the condensation polymerization of diethylenetriaminepentaacetic dianhydride with long chain L-lysine alkyl esters. The corresponding paramagnetic metal complexes were also prepared by the reaction of these ligands with GdCl3. The relaxivities of these metal complexes are higher than that of Gd(DTPA).
1998, 15(3): 19-21
Abstract:
The quantitative relationship between the structure of thio(seleno) phosphate-phosphonates and their herbicidal activity on the rape was investigated using physico-chemical parameters of the substituents and regression analysis. Good QSAR results were obtained, which might be used in guiding the synthesis of compounds with higher activity.
The quantitative relationship between the structure of thio(seleno) phosphate-phosphonates and their herbicidal activity on the rape was investigated using physico-chemical parameters of the substituents and regression analysis. Good QSAR results were obtained, which might be used in guiding the synthesis of compounds with higher activity.
1998, 15(3): 22-25
Abstract:
A series of perovskite complex oxides BaCe1-xRExO3-0.5x (RE=La,Nd,Sm,Eu,Gd,Dy,Ho,Er and Y) were synthesized by sol-gel method. The structure and synthetic process were studied by XRD, TGA and DTA. The ionic conductivities were measured at diffe-rent temperature by ac impedance method. The effects of RE3+ dopant on the conductivities of BaCeO3 were discussed. The synthetic temperature by sol-gel method was 600~800 ℃ lower than that by traditional ceramic method. The ionic conductivities of BaCeO3 doped with RE3+ were 10~40 times as much as that of pure BaCeO3.
A series of perovskite complex oxides BaCe1-xRExO3-0.5x (RE=La,Nd,Sm,Eu,Gd,Dy,Ho,Er and Y) were synthesized by sol-gel method. The structure and synthetic process were studied by XRD, TGA and DTA. The ionic conductivities were measured at diffe-rent temperature by ac impedance method. The effects of RE3+ dopant on the conductivities of BaCeO3 were discussed. The synthetic temperature by sol-gel method was 600~800 ℃ lower than that by traditional ceramic method. The ionic conductivities of BaCeO3 doped with RE3+ were 10~40 times as much as that of pure BaCeO3.
1998, 15(3): 26-29
Abstract:
Some factors affecting the oscillation behavior such as aftertreatment of the AuInSe2 semiconductor film, stirring condition, light and chemical impregnation of the film have been investigated. It is found that the oscillation frequency on the film can be controlled by periodic light illumination and potential modulation.
Some factors affecting the oscillation behavior such as aftertreatment of the AuInSe2 semiconductor film, stirring condition, light and chemical impregnation of the film have been investigated. It is found that the oscillation frequency on the film can be controlled by periodic light illumination and potential modulation.
1998, 15(3): 30-34
Abstract:
The waterborne polyurethane(WPU) with tert-amine groups were prepared. The prepolymers having NCO and tert-amine were synthesized by the reaction of toluene-2,4-diisocyanate with polypropylene glycol, tert-ethanolamine and other multiols, then emulsified in dilute HCl of pH 5~6. The particle size data show that the tert-amine monomer with single hydroxyl is preferable to the dihydroxyl and trihydroxyl tert-amine. The final product WPU showes some characteristics of pseudoplastic fluid and its film has good water-resistance. It is also found that increasing the amounts of tert-amine could remarkably improve the mechanical properties and widen the tan W peak of the product.
The waterborne polyurethane(WPU) with tert-amine groups were prepared. The prepolymers having NCO and tert-amine were synthesized by the reaction of toluene-2,4-diisocyanate with polypropylene glycol, tert-ethanolamine and other multiols, then emulsified in dilute HCl of pH 5~6. The particle size data show that the tert-amine monomer with single hydroxyl is preferable to the dihydroxyl and trihydroxyl tert-amine. The final product WPU showes some characteristics of pseudoplastic fluid and its film has good water-resistance. It is also found that increasing the amounts of tert-amine could remarkably improve the mechanical properties and widen the tan W peak of the product.
1998, 15(3): 35-38
Abstract:
It is found that the electroplating time affected the chemical composition of the electrodeposited Ni-W-P alloy films on p-silicon and their structures. The DTA results showed that the crystal structure of the amorphous Ni-W-P film does not change drastically at 200 ℃ to 500 ℃ under N2. The Ni-W-P film has better thermal stability than that of amorphous Ni-P film.
It is found that the electroplating time affected the chemical composition of the electrodeposited Ni-W-P alloy films on p-silicon and their structures. The DTA results showed that the crystal structure of the amorphous Ni-W-P film does not change drastically at 200 ℃ to 500 ℃ under N2. The Ni-W-P film has better thermal stability than that of amorphous Ni-P film.
1998, 15(3): 39-42
Abstract:
The new polynuclear solid complex of lanthanum(La) with dithiocarbaminoacetic cobalt [Co(HL)2](L=-S2CNHCH2CO2-) was synthesized in microwave oven at 60 ℃. The product was characterized by elemental analysis, IR spectrum, UV absorption spectrum, 1H NMR and molar conductance measurements. The results showed that the composition of the complex was La2(CoL2)3. The preliminary bioassay showed that the complex could significantly inhibit the growth of liver cancer cell, but not affect on the growth of human liver cells.
The new polynuclear solid complex of lanthanum(La) with dithiocarbaminoacetic cobalt [Co(HL)2](L=-S2CNHCH2CO2-) was synthesized in microwave oven at 60 ℃. The product was characterized by elemental analysis, IR spectrum, UV absorption spectrum, 1H NMR and molar conductance measurements. The results showed that the composition of the complex was La2(CoL2)3. The preliminary bioassay showed that the complex could significantly inhibit the growth of liver cancer cell, but not affect on the growth of human liver cells.
1998, 15(3): 43-46
Abstract:
The extraction kinetics of Er3+ by bis(2,4,4-trimethylpentyl) phosphinic acid (HBTMPP) has been investigated using a novel constant interfacial area cell with laminar flow. The effects of concentration of Er(Ⅲ), pH, ion strength of aqueous phase and HBTMPP in organic phase on the extraction rate were studied. The influences of temperature, interfacial area on extraction kinetics were also discussed. The experimental results indicated that the extraction process might be governed by a mixed mechanism of diffusion and chemical reaction.
The extraction kinetics of Er3+ by bis(2,4,4-trimethylpentyl) phosphinic acid (HBTMPP) has been investigated using a novel constant interfacial area cell with laminar flow. The effects of concentration of Er(Ⅲ), pH, ion strength of aqueous phase and HBTMPP in organic phase on the extraction rate were studied. The influences of temperature, interfacial area on extraction kinetics were also discussed. The experimental results indicated that the extraction process might be governed by a mixed mechanism of diffusion and chemical reaction.
1998, 15(3): 47-50
Abstract:
Poly(U-pinene) was brominated by N-bromosuccinimide on its allylic carbon. Then the brominated poly(U-pinene) was activated by AlEt2Cl to initiate the polymerization of styrene (AlEt2Cl alone could not induce the polymerization of styrene). The obtained U-inene/styrene graft copolymer has been characterized by GPC, 1H NMR, and DSC measurements.
Poly(U-pinene) was brominated by N-bromosuccinimide on its allylic carbon. Then the brominated poly(U-pinene) was activated by AlEt2Cl to initiate the polymerization of styrene (AlEt2Cl alone could not induce the polymerization of styrene). The obtained U-inene/styrene graft copolymer has been characterized by GPC, 1H NMR, and DSC measurements.
1998, 15(3): 51-54
Abstract:
Ten title compounds have been prepared by reacting equal mole of 3-aryl 4-amino 5-mercapto-1,2,4-triazoles and aryl carboxylic acids in the presence of phosphorus oxychloride at 98 ℃ for 4~6 h. The structures of the compounds have been characterized by elemental analysis, IR, 1H NMR and MS measurements. All the compounds were preliminary screened for antimicrobial activity against Staphylococcus aureus and Escherichia coli in 0.002% concentration. Some of the compounds exhibited a rather strong biological activity.
Ten title compounds have been prepared by reacting equal mole of 3-aryl 4-amino 5-mercapto-1,2,4-triazoles and aryl carboxylic acids in the presence of phosphorus oxychloride at 98 ℃ for 4~6 h. The structures of the compounds have been characterized by elemental analysis, IR, 1H NMR and MS measurements. All the compounds were preliminary screened for antimicrobial activity against Staphylococcus aureus and Escherichia coli in 0.002% concentration. Some of the compounds exhibited a rather strong biological activity.
1998, 15(3): 55-58
Abstract:
Under certain physiological conditions the organogermanium compound Ge-132 in concentration of 1~10 mmol/L was found to have a strong suppression on the non-enzymatic glycosylation (Maillard reaction) of some amino acids: His, Arg, Val and Gly with glucose.
Under certain physiological conditions the organogermanium compound Ge-132 in concentration of 1~10 mmol/L was found to have a strong suppression on the non-enzymatic glycosylation (Maillard reaction) of some amino acids: His, Arg, Val and Gly with glucose.
1998, 15(3): 59-62
Abstract:
In view of the biological activity of s-triazolo [3,4-b]-1,3,4-thiadiazole fused heterocyclic derivatives, nine novel compounds 3-((4'-chloro)-3'-ethyl-1'-methyl-5'-pyrazolyl)-6-substituted-s-triazolo [3,4-b]-1,3,4-thiadiazoles (4a~g,5,6) were synthesized by condensation of carboxylic acid with 4-amino-3-((4'-chloro)-3'-ethyl-1'-methyl-5'-pyrazolyl)-1,2,4-triazole-5-thione. Their structures were characterized by elemental analysis, 1H NMR, IR and MS spectroscopy. The preliminary bioassay tests showed that compound 3 exhibited plant growth regulation activity and 4b, 4d and 6 possessed moderate fungicidal activity.
In view of the biological activity of s-triazolo [3,4-b]-1,3,4-thiadiazole fused heterocyclic derivatives, nine novel compounds 3-((4'-chloro)-3'-ethyl-1'-methyl-5'-pyrazolyl)-6-substituted-s-triazolo [3,4-b]-1,3,4-thiadiazoles (4a~g,5,6) were synthesized by condensation of carboxylic acid with 4-amino-3-((4'-chloro)-3'-ethyl-1'-methyl-5'-pyrazolyl)-1,2,4-triazole-5-thione. Their structures were characterized by elemental analysis, 1H NMR, IR and MS spectroscopy. The preliminary bioassay tests showed that compound 3 exhibited plant growth regulation activity and 4b, 4d and 6 possessed moderate fungicidal activity.
1998, 15(3): 63-66
Abstract:
By using the methods of Electron Paramagnetic Resonance(EPR)、 chemilumineseence and fluoresence spectrophotometry, the contents of free radicals、 superoxide dismutases(SOD) and water soluble lipid peroxides in tears in the normal eyes(100 cases) and keratoplasty eyes(42 cases) have been investigated. The results indicated that the spin density of free radicals was (3.6±0.58) × 1012 spins/mL, SOD was (3.84±1.45) μg/L, water soluble lipid peroxide was (12.912±1.691) U/mL in the normal tears. Two peaks were found in every target after 24 hours and 21 day of the keratoplasty operation. Both peaks regularily. An obvious interrelation was there in every pair of the three targets. However, the special changes of 5 cases of 42 cases proved free radicals and lipid peroxides increased continuously and the rejection was inereased. These findings suggest that there is free radical reaction mechanism in the rejection and that after keratoplasty supervising and determining free radical、 SOD and water soluble lipid peroxide are important for preventing the rejection.
By using the methods of Electron Paramagnetic Resonance(EPR)、 chemilumineseence and fluoresence spectrophotometry, the contents of free radicals、 superoxide dismutases(SOD) and water soluble lipid peroxides in tears in the normal eyes(100 cases) and keratoplasty eyes(42 cases) have been investigated. The results indicated that the spin density of free radicals was (3.6±0.58) × 1012 spins/mL, SOD was (3.84±1.45) μg/L, water soluble lipid peroxide was (12.912±1.691) U/mL in the normal tears. Two peaks were found in every target after 24 hours and 21 day of the keratoplasty operation. Both peaks regularily. An obvious interrelation was there in every pair of the three targets. However, the special changes of 5 cases of 42 cases proved free radicals and lipid peroxides increased continuously and the rejection was inereased. These findings suggest that there is free radical reaction mechanism in the rejection and that after keratoplasty supervising and determining free radical、 SOD and water soluble lipid peroxide are important for preventing the rejection.
1998, 15(3): 67-69
Abstract:
The title Electrophotographic sensitizer was synthesized in 4 steps. Its structure has been confirmed by IR, 1H NMR, fluorescence spectroscopy, elemental analysis and UV-Vis spectrometry. The dye showed a high sensitivity for poly-N-vinylcarbazole in electrophotography.
The title Electrophotographic sensitizer was synthesized in 4 steps. Its structure has been confirmed by IR, 1H NMR, fluorescence spectroscopy, elemental analysis and UV-Vis spectrometry. The dye showed a high sensitivity for poly-N-vinylcarbazole in electrophotography.
1998, 15(3): 70-72
Abstract:
The characteristics of petroporphyrin biomarkers in Xixiepo oil has been investigated by UV-Vis, MS and HPLC techniques. The UV-Vis spectrum showed that most of the petroporphyrins in this area are nickel derivatives. The MS results on the analysis of the crude oil showed that there are six types of porphyrin at least as follows: ETIO, DPEP, Di-DPEP, Rhodo-ETIO, Rhodo-DPEP and Rhodo-Di-DPEP, and the ratio of DPEP to ETIO 0.33 illustrates the higher oil maturity.
The characteristics of petroporphyrin biomarkers in Xixiepo oil has been investigated by UV-Vis, MS and HPLC techniques. The UV-Vis spectrum showed that most of the petroporphyrins in this area are nickel derivatives. The MS results on the analysis of the crude oil showed that there are six types of porphyrin at least as follows: ETIO, DPEP, Di-DPEP, Rhodo-ETIO, Rhodo-DPEP and Rhodo-Di-DPEP, and the ratio of DPEP to ETIO 0.33 illustrates the higher oil maturity.
1998, 15(3): 73-75
Abstract:
Seven complexes of tetra(4-hydroxyphenyl) porphyrins with Cr, Mn, Fe, Co, Ni, Cu and Zn have been synthesized in mixed solvents CH2Cl2+ DMF. The structures and compositions of the complexes were determined by elemental analysis, UV-Vis, FTIR photoacoustic spectrum, 1H NMR and molar conductance measurements.
Seven complexes of tetra(4-hydroxyphenyl) porphyrins with Cr, Mn, Fe, Co, Ni, Cu and Zn have been synthesized in mixed solvents CH2Cl2+ DMF. The structures and compositions of the complexes were determined by elemental analysis, UV-Vis, FTIR photoacoustic spectrum, 1H NMR and molar conductance measurements.
1998, 15(3): 76-78
Abstract:
Three rare earth oxyfluorides Sm2O3/4CeF3, Nd2O3/4CeF3 and Y2O3/4CeF3 were prepared. They were active in oxidative dehydrogenation of propane and isobutane with high selectivity to propene and isobutene. The propane is easier to dehydrogenate than isobtuane, and the isobutane is easier to crack. XRD measurements indicated the existence of new phase such as CeO2 and REF3 or REOF as a result of the exchange between F- and O2- during the preparation. The in-situ Raman spectra implied that O2- was the active species.
Three rare earth oxyfluorides Sm2O3/4CeF3, Nd2O3/4CeF3 and Y2O3/4CeF3 were prepared. They were active in oxidative dehydrogenation of propane and isobutane with high selectivity to propene and isobutene. The propane is easier to dehydrogenate than isobtuane, and the isobutane is easier to crack. XRD measurements indicated the existence of new phase such as CeO2 and REF3 or REOF as a result of the exchange between F- and O2- during the preparation. The in-situ Raman spectra implied that O2- was the active species.
1998, 15(3): 79-81
Abstract:
Ultrafine silica particles ranging from 10 to 20 nm were prepared by sol-gel method and n-butanol azeotropic distillation from water glass using ethyl acetate as a latene acid reagent. The gelling process of the water glass in the presence of ethyl acetate was studied.
Ultrafine silica particles ranging from 10 to 20 nm were prepared by sol-gel method and n-butanol azeotropic distillation from water glass using ethyl acetate as a latene acid reagent. The gelling process of the water glass in the presence of ethyl acetate was studied.
1998, 15(3): 82-84
Abstract:
In the study of the solubility properties of the system of Sm(ClO4)3-BAPHDCA-H2O at 30 ℃ in the whole concentration range by phase equilibrium method a ternary compound Sm(BAPHDCA)2(ClO4)3 ° H2O has been found. According to the phase equilibrium results the complex was prepared and characterized by chemical and elemenal analysis, IR spectrometry and TG-DTG techniques.
In the study of the solubility properties of the system of Sm(ClO4)3-BAPHDCA-H2O at 30 ℃ in the whole concentration range by phase equilibrium method a ternary compound Sm(BAPHDCA)2(ClO4)3 ° H2O has been found. According to the phase equilibrium results the complex was prepared and characterized by chemical and elemenal analysis, IR spectrometry and TG-DTG techniques.
1998, 15(3): 85-87
Abstract:
The hydrolytic stability of lauryl polyoxyethylene phosphate in aqueous solution has been studied by using the kinetic model. The results showed that the hydrolysis reaction followed first order with respect to phosphate concentration. The activation energy increased with the pH value of the buffered solution, but the rate constant decreased as pH increased. Addition of NaCl weakly suppressed the hydrolysis.
The hydrolytic stability of lauryl polyoxyethylene phosphate in aqueous solution has been studied by using the kinetic model. The results showed that the hydrolysis reaction followed first order with respect to phosphate concentration. The activation energy increased with the pH value of the buffered solution, but the rate constant decreased as pH increased. Addition of NaCl weakly suppressed the hydrolysis.
1998, 15(3): 88-90
Abstract:
Eight T-[2-(2.4-dichlorophenoxy) propionyloxy] alkyl phosphonates were synthesized and characterized by IR, 1H NMR and MS. The relationship between their substituents and biological activities have been discussed. All of the compounds showed a certain herbicidal selectivity.
Eight T-[2-(2.4-dichlorophenoxy) propionyloxy] alkyl phosphonates were synthesized and characterized by IR, 1H NMR and MS. The relationship between their substituents and biological activities have been discussed. All of the compounds showed a certain herbicidal selectivity.
1998, 15(3): 91-93
Abstract:
The degradation behavior of poly(X-caprolactone)(PCL)/poly(d,l-lactide)(PLA) blend films prepared by solution casting method have been studied in the phosphate buffer solution containing pseudomonas lipase(PS). PCL was found to be degraded and PLA remained as before. The SEM results indicated that the change both in the surface and inside of the film was owing to the degradation of PCL component in the blends.
The degradation behavior of poly(X-caprolactone)(PCL)/poly(d,l-lactide)(PLA) blend films prepared by solution casting method have been studied in the phosphate buffer solution containing pseudomonas lipase(PS). PCL was found to be degraded and PLA remained as before. The SEM results indicated that the change both in the surface and inside of the film was owing to the degradation of PCL component in the blends.
1998, 15(3): 94-96
Abstract:
Cotton stalk cellulose ether(CE) having active epoxy groups was prepared by reaction of alkaline cotton stalk cellulose with epichlorohydrin. Two nitrogen containing cotton stalk cellulose derivatives(CENB, CENH) were then obtained by reacting CE with 5,8-diazadodecane and ethylenediamine, respectively. They exhibited better adsorptive capacities to Hg2+, Pb2+, Cd2+, Cr3+ and Cu2+ ions and could be used repeatedly as anion exchanger.
Cotton stalk cellulose ether(CE) having active epoxy groups was prepared by reaction of alkaline cotton stalk cellulose with epichlorohydrin. Two nitrogen containing cotton stalk cellulose derivatives(CENB, CENH) were then obtained by reacting CE with 5,8-diazadodecane and ethylenediamine, respectively. They exhibited better adsorptive capacities to Hg2+, Pb2+, Cd2+, Cr3+ and Cu2+ ions and could be used repeatedly as anion exchanger.
1998, 15(3): 97-99
Abstract:
The space structures of the model compounds of three soluble polyimides have been simulated through the semi-empirical molecular orbital calculation. The mechanism of the electrochemical reactions of polyimides has been verified based on the most favorable conformations of the monomeric units obtained.
The space structures of the model compounds of three soluble polyimides have been simulated through the semi-empirical molecular orbital calculation. The mechanism of the electrochemical reactions of polyimides has been verified based on the most favorable conformations of the monomeric units obtained.
1998, 15(3): 100-102
Abstract:
The power-time curves of E.Coli effected by the title complex (Co(Ⅲ)-2,4-L) at different temperatures have been determined by a microcalorimeter LKB 2277 Bioactivity Monitor. The multiplication rate constant k, generation time G, inhibitory extent I and heat generations Q, Q0 and -Q0 have been calculated.
The power-time curves of E.Coli effected by the title complex (Co(Ⅲ)-2,4-L) at different temperatures have been determined by a microcalorimeter LKB 2277 Bioactivity Monitor. The multiplication rate constant k, generation time G, inhibitory extent I and heat generations Q, Q0 and -Q0 have been calculated.
1998, 15(3): 103-105
Abstract:
The solid state reaction mechanism between Li2CO3 and TiO2 forming Li2TiO3 has been studied by XRD. The relationship between reaction rate and temperature and the dependence of the reactant fraction (a) on the heating time were investigated. The activation energy of the reaction has been calculated to be 166.2 kJ/mol. The reaction mechanism conformed to the Ginstling-Brounstein model. It is proposed that Li+ ions diffuse into TiO2 particles during the reaction.
The solid state reaction mechanism between Li2CO3 and TiO2 forming Li2TiO3 has been studied by XRD. The relationship between reaction rate and temperature and the dependence of the reactant fraction (a) on the heating time were investigated. The activation energy of the reaction has been calculated to be 166.2 kJ/mol. The reaction mechanism conformed to the Ginstling-Brounstein model. It is proposed that Li+ ions diffuse into TiO2 particles during the reaction.
1998, 15(3): 106-108
Abstract:
Sodium bis(2-ethylhexyl polyoxyalkylene) sulfosuccinates of different polymerization numbers were synthesized. The activities of lipase in the reversed micelles formed by synthetic surfactants and normal AOT in isooctane have been compared in the process of catalytic hydrolysis of olive oil. The results showed the activity of lipase in sodium bis(2-ethylhexyl polyoxyethylene) sulfosuccinate(n=2.3) /isooctane reversed micelles was 2-fold higher than that in the normal AOT/isooctane reversed micelles.
Sodium bis(2-ethylhexyl polyoxyalkylene) sulfosuccinates of different polymerization numbers were synthesized. The activities of lipase in the reversed micelles formed by synthetic surfactants and normal AOT in isooctane have been compared in the process of catalytic hydrolysis of olive oil. The results showed the activity of lipase in sodium bis(2-ethylhexyl polyoxyethylene) sulfosuccinate(n=2.3) /isooctane reversed micelles was 2-fold higher than that in the normal AOT/isooctane reversed micelles.
1998, 15(3): 109-111
Abstract:
The influences of pH value and added salt of the system, as well as the active groups of the regenerable chitin on the adsorption of Cr(Ⅵ) by regenerable chitin have been investigated. The thermodynamic parameters in this exothermic adsorption process have been determined. The results indicated that the free amino groups on the surface of the regenerable chitin appeared the adsorption center.
The influences of pH value and added salt of the system, as well as the active groups of the regenerable chitin on the adsorption of Cr(Ⅵ) by regenerable chitin have been investigated. The thermodynamic parameters in this exothermic adsorption process have been determined. The results indicated that the free amino groups on the surface of the regenerable chitin appeared the adsorption center.
1998, 15(3): 112-113
Abstract:
Five matel Complexes of N,N'-disalicylidene-1,2-bis(4-methoxyphenyl)ethylenediamine have been synthesized and characterized by elemental analysis, IR, electron spectrum and conductivity measurements. The metal ion M(Ⅱ)(Fe, Co, Ni, Mn) was found to be coordinated to the azomethene nitrogen and phenolic oxygen of the ligand. The complexes were thought to have a square planar structure. The compounds showed a weak bacteriostatic action against pyricularia oryzal, septoria apiicola.
Five matel Complexes of N,N'-disalicylidene-1,2-bis(4-methoxyphenyl)ethylenediamine have been synthesized and characterized by elemental analysis, IR, electron spectrum and conductivity measurements. The metal ion M(Ⅱ)(Fe, Co, Ni, Mn) was found to be coordinated to the azomethene nitrogen and phenolic oxygen of the ligand. The complexes were thought to have a square planar structure. The compounds showed a weak bacteriostatic action against pyricularia oryzal, septoria apiicola.
1998, 15(3): 114-115
Abstract:
The title lithium-copper-manganese complex oxide, a spineltype metal oxide, was prepared by a coprecipitation/thermal crystallization method. Its Li+ extraction/insertion process was found to be a topotactic reaction. It had an ion-exchange capacity of 5.0 mmol/g for Li+ and showed also a memorial ion-exchange property for Li+.
The title lithium-copper-manganese complex oxide, a spineltype metal oxide, was prepared by a coprecipitation/thermal crystallization method. Its Li+ extraction/insertion process was found to be a topotactic reaction. It had an ion-exchange capacity of 5.0 mmol/g for Li+ and showed also a memorial ion-exchange property for Li+.
1998, 15(3): 116-117
Abstract:
Five title complexes were synthesized. The characterization results obtained from elemental analysis, MS, 1H NMR and thermogravimetric analysis revealed that the complexes have a general formula [C5H4C(CH3)2CH2CH=CH2]° LnCl2° MgCl2° THF, where Ln=La, Nd, Sm, Gd and Lu.
Five title complexes were synthesized. The characterization results obtained from elemental analysis, MS, 1H NMR and thermogravimetric analysis revealed that the complexes have a general formula [C5H4C(CH3)2CH2CH=CH2]° LnCl2° MgCl2° THF, where Ln=La, Nd, Sm, Gd and Lu.
