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1993 Volume 10 Issue 3
1993, 10(3): 1-7
Abstract:
The recent advancement of metalphthalocyanine derivatives has been reviewed briefly. The accent is the formation of LB films, their orientation, electric conductivity, vapour sensibility and application for molecule electronic devices.
The recent advancement of metalphthalocyanine derivatives has been reviewed briefly. The accent is the formation of LB films, their orientation, electric conductivity, vapour sensibility and application for molecule electronic devices.
1993, 10(3): 8-11
Abstract:
A Schiff base(H3L) has been obtained by the reaction of 3,4-dihydroxybenzaldehyde with anthranilic acid in ethyl alcohol. Nine complexes of this Schiff base with lanthanide ions have been synthesized in the presence of triethylamine. Elemental analysis and conductance measurements show that the complexes have the general formula of RE(L)nH2O, (RE=La,Pr,Nd,Sm,n=3;RE=Gd,Dy, Ho, Yb, Y,n=4), both Gd and Y complexes belong to that with heavier REs. No nitrate was found in the complexes. The complexes were characterized by magnetic susceptibility, TG-DTA, IR spectra and NMR measurements. The Ligand, which acts as quadriderntate, coordinates with RE(Ⅲ) in "gauche" form.
A Schiff base(H3L) has been obtained by the reaction of 3,4-dihydroxybenzaldehyde with anthranilic acid in ethyl alcohol. Nine complexes of this Schiff base with lanthanide ions have been synthesized in the presence of triethylamine. Elemental analysis and conductance measurements show that the complexes have the general formula of RE(L)nH2O, (RE=La,Pr,Nd,Sm,n=3;RE=Gd,Dy, Ho, Yb, Y,n=4), both Gd and Y complexes belong to that with heavier REs. No nitrate was found in the complexes. The complexes were characterized by magnetic susceptibility, TG-DTA, IR spectra and NMR measurements. The Ligand, which acts as quadriderntate, coordinates with RE(Ⅲ) in "gauche" form.
1993, 10(3): 12-15
Abstract:
The enthalpies of solution of two Mg-borates(2MgO·2B2O3·MgCl2·14H2O and MgO·2B2O3·9H2O) in 0.997mol/L HCl solution were measured by using isoperibel reaction colorimeter.The standard enthalpies of formation of the two Mg-borate salts were obtained according to thermochemistry theory. The values are -8638.42kJ/tool and -5807.07k J/mol separately. The standard molar entropy of MgO·2B2O3·9H2O was also given.
The enthalpies of solution of two Mg-borates(2MgO·2B2O3·MgCl2·14H2O and MgO·2B2O3·9H2O) in 0.997mol/L HCl solution were measured by using isoperibel reaction colorimeter.The standard enthalpies of formation of the two Mg-borate salts were obtained according to thermochemistry theory. The values are -8638.42kJ/tool and -5807.07k J/mol separately. The standard molar entropy of MgO·2B2O3·9H2O was also given.
1993, 10(3): 16-19
Abstract:
A method was suggested for the study of immobilized enzyme kinetics with internal diffusion limitations in a fixed-bed reactor using single size immobilized enzyme. According to the characters of the reactions at enough high and low concentrations of substrates, corresponding to zero and first order reactions respectively, the intrinsic kinetics parameters and internal diffusion parameters for reaction of glucose isomerization were determined. The values of effectiveness factor were calculated and compared with that obtained in the experiment.
A method was suggested for the study of immobilized enzyme kinetics with internal diffusion limitations in a fixed-bed reactor using single size immobilized enzyme. According to the characters of the reactions at enough high and low concentrations of substrates, corresponding to zero and first order reactions respectively, the intrinsic kinetics parameters and internal diffusion parameters for reaction of glucose isomerization were determined. The values of effectiveness factor were calculated and compared with that obtained in the experiment.
1993, 10(3): 20-23
Abstract:
The effects of La2O3, Y2O3 and mixed rare earth oxides on the crystallization, melting behavior and the dynamic mechanical properties of isotactic polypropylene in its composites with oxides have been investigated by means of DSC and viscoelastometry. Y2O3 and the mixed rare earth oxides appeared to be an α and β-nucleator and La2O3 is an α-nucleator for iPP. The crystallinity degree increases in order of PP/Y2O3,PP/mixed rare earth oxides,PP/La2O3 and pure iPP. Tanδ values of the samples containning both α and β-phases are lower than that of the iPP and PP/La2O3 in the region near Tg relaxation. Dynamic storage modulus E' in the PP/Y2O3 and PP/mixed rare earth oxides was higher than that of PP/La2O3 and iPP in the range of -50℃ to 50℃, but lower in 50℃ to 145℃.These results are attributable to the β-phase of polymer crystal in the samples.
The effects of La2O3, Y2O3 and mixed rare earth oxides on the crystallization, melting behavior and the dynamic mechanical properties of isotactic polypropylene in its composites with oxides have been investigated by means of DSC and viscoelastometry. Y2O3 and the mixed rare earth oxides appeared to be an α and β-nucleator and La2O3 is an α-nucleator for iPP. The crystallinity degree increases in order of PP/Y2O3,PP/mixed rare earth oxides,PP/La2O3 and pure iPP. Tanδ values of the samples containning both α and β-phases are lower than that of the iPP and PP/La2O3 in the region near Tg relaxation. Dynamic storage modulus E' in the PP/Y2O3 and PP/mixed rare earth oxides was higher than that of PP/La2O3 and iPP in the range of -50℃ to 50℃, but lower in 50℃ to 145℃.These results are attributable to the β-phase of polymer crystal in the samples.
1993, 10(3): 24-27
Abstract:
A blend elastomer has been prepared from hydroxyl-terminated polypropylene carbonate (PPC) and nitrile-butadiene rubber(NBR) in the presence of dicumyl peroxide and 2-mercaptobenzimidazole. The dynamic mechanical analysis and TEM photos showed that the PPC/NBR blend has two-phase structure. Its tensile strength and elongation at break were greatly increased. The oil resistance and heat stability of PPC/NBR elastomers are as good as pure NBR elastomer,
A blend elastomer has been prepared from hydroxyl-terminated polypropylene carbonate (PPC) and nitrile-butadiene rubber(NBR) in the presence of dicumyl peroxide and 2-mercaptobenzimidazole. The dynamic mechanical analysis and TEM photos showed that the PPC/NBR blend has two-phase structure. Its tensile strength and elongation at break were greatly increased. The oil resistance and heat stability of PPC/NBR elastomers are as good as pure NBR elastomer,
1993, 10(3): 28-31
Abstract:
The rare earth complexes with m-nitrobenzoic acid (LnL3·nH2O, n=2,Ln=La-Lu and Y; n=0, Ln=Sc. HL=m-nitrobenzoic acid) were synthesized and characterized by elemental analysis and IR spectra. The mechanism of thermal decomposition of complexes were studied by means of TG-DTA and high temperature X-ray diffractometry. The activation energies and enthalpy changes of dehydration process of LnL3·2H2O were calculated. The phase change process of the complexes has been studied by DSC. The ultrafinity of the products of decomposition was observed.
The rare earth complexes with m-nitrobenzoic acid (LnL3·nH2O, n=2,Ln=La-Lu and Y; n=0, Ln=Sc. HL=m-nitrobenzoic acid) were synthesized and characterized by elemental analysis and IR spectra. The mechanism of thermal decomposition of complexes were studied by means of TG-DTA and high temperature X-ray diffractometry. The activation energies and enthalpy changes of dehydration process of LnL3·2H2O were calculated. The phase change process of the complexes has been studied by DSC. The ultrafinity of the products of decomposition was observed.
1993, 10(3): 32-34
Abstract:
High-purity ultrafine powder of BaTiO3 was prepared by H2O2 oxidation hydrothermal combined method. H2O2 oxidation was performed at room temperature,hydrothermal-treatment at 140℃.When solution of titanium peroxide was mixed with excess of barium hydroxide solution and hydrothermally treated for 6h, single phase powder of BaTiO3 was obtained with average particle size 55nm and a narrow particle size distribution. From TiO42- solution TiO2·xH2O, anatase and rutile also could be obtained, but the crystals of TiO2 were less effective for BaTiO3 preparation. Anatase powder formed BaTiO3 by hydrothermal-treatment at 140℃ for 6h gave BaTiO3 of 0.12μm size in average.
High-purity ultrafine powder of BaTiO3 was prepared by H2O2 oxidation hydrothermal combined method. H2O2 oxidation was performed at room temperature,hydrothermal-treatment at 140℃.When solution of titanium peroxide was mixed with excess of barium hydroxide solution and hydrothermally treated for 6h, single phase powder of BaTiO3 was obtained with average particle size 55nm and a narrow particle size distribution. From TiO42- solution TiO2·xH2O, anatase and rutile also could be obtained, but the crystals of TiO2 were less effective for BaTiO3 preparation. Anatase powder formed BaTiO3 by hydrothermal-treatment at 140℃ for 6h gave BaTiO3 of 0.12μm size in average.
1993, 10(3): 35-38
Abstract:
The effects of some oxide intermediate layers on the electrochemical behavior and characteristics of oxide-coated titanium electrodes Ti/PbO2, Ti/Co3O4 and Ti/CuCO2O4 have been investigated.The results showed that the intermediate layers of Co3O4, PdOx, SnO2 and Sb2O3 could markedly decrease the interface resistance of the electrodes. The electrode Ti/PbO2 with intermediate layer of (Sb2O3+PdOx) and the electrode Ti/Co3O4 with intermediate layer of (SnO2+PdOx) showed nearly the same reaction activity for anodic evolution of Cl2 as the industrial electrode consisting of Ti/RuO2+TiO2, but higher oxygen overpotentials than the latter.
The effects of some oxide intermediate layers on the electrochemical behavior and characteristics of oxide-coated titanium electrodes Ti/PbO2, Ti/Co3O4 and Ti/CuCO2O4 have been investigated.The results showed that the intermediate layers of Co3O4, PdOx, SnO2 and Sb2O3 could markedly decrease the interface resistance of the electrodes. The electrode Ti/PbO2 with intermediate layer of (Sb2O3+PdOx) and the electrode Ti/Co3O4 with intermediate layer of (SnO2+PdOx) showed nearly the same reaction activity for anodic evolution of Cl2 as the industrial electrode consisting of Ti/RuO2+TiO2, but higher oxygen overpotentials than the latter.
1993, 10(3): 39-41
Abstract:
The solid solutions of La2-xCaxNiO4 (0 ≤x ≤1.4) were prepared and compared with solid solutions of La2-xSrxNiO4. All the members of the system are of tetragonal K2NiF4 structure. Their crystal parameters a,c and cell volume were found to be gradually decreased with the increase of x. The electrical resistivity of La2-xCaxNiO4 progressively increases but that of La2-xSrxNiO4 gradually decreases with increasing x at room temperature. The difference in electrical behavior is interpreted in terms of the change of the electronic configuration of Ni3+.
The solid solutions of La2-xCaxNiO4 (0 ≤x ≤1.4) were prepared and compared with solid solutions of La2-xSrxNiO4. All the members of the system are of tetragonal K2NiF4 structure. Their crystal parameters a,c and cell volume were found to be gradually decreased with the increase of x. The electrical resistivity of La2-xCaxNiO4 progressively increases but that of La2-xSrxNiO4 gradually decreases with increasing x at room temperature. The difference in electrical behavior is interpreted in terms of the change of the electronic configuration of Ni3+.
1993, 10(3): 42-46
Abstract:
Adenine derivatives as pharmaceuticals-eritadenine (1), ethyl 4-(6-amino-9H-purine-9-yl)-2(R), 3(R)-dihydroxybutyrate (1a),β-adenylpropionic acid (2) and ethyl β-adenylpropionate (2a) have been synthesized by solid-liquid phase transfer eatalysis. The effects of reaction conditions on the yields were studied. The results showed that PEG is a good phase transfer catalyst for the reaction.
Adenine derivatives as pharmaceuticals-eritadenine (1), ethyl 4-(6-amino-9H-purine-9-yl)-2(R), 3(R)-dihydroxybutyrate (1a),β-adenylpropionic acid (2) and ethyl β-adenylpropionate (2a) have been synthesized by solid-liquid phase transfer eatalysis. The effects of reaction conditions on the yields were studied. The results showed that PEG is a good phase transfer catalyst for the reaction.
1993, 10(3): 47-50
Abstract:
Eosin dye (EO)-diphenyliodonium salt(DPIO) system has been synthesized as a new dye photoinitiator sensitive to visible spectral region. Its maximum absorption is at 527nm. The eosiniodonium system does not react in the dark.but on irradiation with visible light,the photoinduced electron transfer sensitive reaction may lead to the bleaching of dye and cleavage of iodonium. The produced free-radicals could initiate the curing of acrylate film composed of epoxy 6101 diaerylate and pentaerythritol triacrylate (2:1 W/W). The photocuring rate was found to be depended strongly on the composition of the system. The diiodonium salts EO (Ph2I)2 appeared more effective than monoiodonium salt EOEt (Ph2I), while the bimolecular system (EONa2+Ph2I+BF4-) failed to cause any crosslinking reaction in the same coudition. It may be concluded that the photoinduced electron transfer photosensitization by the ion-pairs is a high efficient pathway to overcome the diffusion controlled limitation.
Eosin dye (EO)-diphenyliodonium salt(DPIO) system has been synthesized as a new dye photoinitiator sensitive to visible spectral region. Its maximum absorption is at 527nm. The eosiniodonium system does not react in the dark.but on irradiation with visible light,the photoinduced electron transfer sensitive reaction may lead to the bleaching of dye and cleavage of iodonium. The produced free-radicals could initiate the curing of acrylate film composed of epoxy 6101 diaerylate and pentaerythritol triacrylate (2:1 W/W). The photocuring rate was found to be depended strongly on the composition of the system. The diiodonium salts EO (Ph2I)2 appeared more effective than monoiodonium salt EOEt (Ph2I), while the bimolecular system (EONa2+Ph2I+BF4-) failed to cause any crosslinking reaction in the same coudition. It may be concluded that the photoinduced electron transfer photosensitization by the ion-pairs is a high efficient pathway to overcome the diffusion controlled limitation.
1993, 10(3): 51-53
Abstract:
The LB films prepared from the mixture of 3-tricyanovinyl-N-hexadeeylindole and arachidie acid have been studied. In the plateau regions on the π-A curves of the films there occurs a phase transition. The UV spectra of the films show that indole molecules form H-aggregates in the ordered films. The morphorlogy and structure of the films were characterized by scanning electron microscopy and X-ray dfffractormetr.
The LB films prepared from the mixture of 3-tricyanovinyl-N-hexadeeylindole and arachidie acid have been studied. In the plateau regions on the π-A curves of the films there occurs a phase transition. The UV spectra of the films show that indole molecules form H-aggregates in the ordered films. The morphorlogy and structure of the films were characterized by scanning electron microscopy and X-ray dfffractormetr.
1993, 10(3): 54-56
Abstract:
The chemical composition and thermal properties of the products on the carbon cathode in overdischarged Li/SOCl2 cells have been investigated by DSC, EDAX and XPS methods. The rate of the exothermic reaction and half life of the hazardous products have been evaluated according to Ozawa's formulation. The results showed that the solid deposits on the passivated cathode were composed of LiCI,Li2S, Li2S2, LixSy,S and elemental lithium. The explosion of the cell at overdiseharged condition is mainly caused by the well-dispersed mixture of fine elemental sulphur and lithium.
The chemical composition and thermal properties of the products on the carbon cathode in overdischarged Li/SOCl2 cells have been investigated by DSC, EDAX and XPS methods. The rate of the exothermic reaction and half life of the hazardous products have been evaluated according to Ozawa's formulation. The results showed that the solid deposits on the passivated cathode were composed of LiCI,Li2S, Li2S2, LixSy,S and elemental lithium. The explosion of the cell at overdiseharged condition is mainly caused by the well-dispersed mixture of fine elemental sulphur and lithium.
1993, 10(3): 57-59
Abstract:
The stable oil-in-water miniemulsion were prepared using mixed emulsifier comprising a mixture of ionic surfactants (quaternaryammonium compounds) and long chain fatty alcohols (C8 to C16) in low concentration. The chain length of the fatty alcohols, mole ratio of surfactant to fatty alcohol appeared an important factor influencing the formation of miniemulsions. The temperature of emulsification, property of oil phase and volume fraction of internal phase also affected the oil droplet size and the stability of the emulsion. The stabilization of emulsions has been interpreted in terms of the formation of the lyotropic liquid crystals.
The stable oil-in-water miniemulsion were prepared using mixed emulsifier comprising a mixture of ionic surfactants (quaternaryammonium compounds) and long chain fatty alcohols (C8 to C16) in low concentration. The chain length of the fatty alcohols, mole ratio of surfactant to fatty alcohol appeared an important factor influencing the formation of miniemulsions. The temperature of emulsification, property of oil phase and volume fraction of internal phase also affected the oil droplet size and the stability of the emulsion. The stabilization of emulsions has been interpreted in terms of the formation of the lyotropic liquid crystals.
1993, 10(3): 60-62
Abstract:
Coal, pitch, polycyclic aromatic hydrocarbons and other organic compounds:anthraquinone,triphenylphosphine, carbazole, purine, diphenylguanidine, phenanthroline, triazole were ablated by pulsed laser beam in high vacuum, and their products were monitored with negative ion mass spectrometry. The results showed that many organic species can generate fullerene anions, even though they consist of other non-carbon atoms such as H, O, N, P, but with at least one six-member aromatic ring. The Structures and compositions of the organic species showed a certain effect on the generation of the fullerene.
Coal, pitch, polycyclic aromatic hydrocarbons and other organic compounds:anthraquinone,triphenylphosphine, carbazole, purine, diphenylguanidine, phenanthroline, triazole were ablated by pulsed laser beam in high vacuum, and their products were monitored with negative ion mass spectrometry. The results showed that many organic species can generate fullerene anions, even though they consist of other non-carbon atoms such as H, O, N, P, but with at least one six-member aromatic ring. The Structures and compositions of the organic species showed a certain effect on the generation of the fullerene.
1993, 10(3): 63-65
Abstract:
A series of linear carboxy-containing polyaryl ether sulfones (PES) with high molecular weight were synthesized directly by using phenolphthalin as bisohenol monomer. No chemical degradation in macromolecule was observed, which is usually difficult to be avoided in preparing ion-contain-ing polymers by the traditional macromolecular reaction. Synthesis has been carried out conveniently either in acid-form or in salt-form, with a desired degree of earboxylation. The results of DSC deterruination indicated that the Tg of the acid-form of earboxylated PES decreased linearly with the increase of carboxylation degree.
A series of linear carboxy-containing polyaryl ether sulfones (PES) with high molecular weight were synthesized directly by using phenolphthalin as bisohenol monomer. No chemical degradation in macromolecule was observed, which is usually difficult to be avoided in preparing ion-contain-ing polymers by the traditional macromolecular reaction. Synthesis has been carried out conveniently either in acid-form or in salt-form, with a desired degree of earboxylation. The results of DSC deterruination indicated that the Tg of the acid-form of earboxylated PES decreased linearly with the increase of carboxylation degree.
1993, 10(3): 66-67
Abstract:
The inhibiting effects of five 1-acyl formyl-4-F4'-(2,2,6,6-tetramethyl piperidine)]thiosemicarbazides (ATSCPO) on radical polymerization of methyl methaerylate(MMA), initiated by azobisisobutyronitrile have been studied by dilatometric method. The inhibiting effects of the ATSCPO were only one third of that of TMHPO (2,2,6,6-tetramethyl-4-hydroxyl-piperidine-1-oxy) even used in the amount of 9.98×10-3% to the amount of MMA monomer. The effects of ATSCPO on the conversion and rate of polymerization as well as the molecular weight of polymer were briefly discussed.
The inhibiting effects of five 1-acyl formyl-4-F4'-(2,2,6,6-tetramethyl piperidine)]thiosemicarbazides (ATSCPO) on radical polymerization of methyl methaerylate(MMA), initiated by azobisisobutyronitrile have been studied by dilatometric method. The inhibiting effects of the ATSCPO were only one third of that of TMHPO (2,2,6,6-tetramethyl-4-hydroxyl-piperidine-1-oxy) even used in the amount of 9.98×10-3% to the amount of MMA monomer. The effects of ATSCPO on the conversion and rate of polymerization as well as the molecular weight of polymer were briefly discussed.
1993, 10(3): 68-71
Abstract:
The ESR spectra of VO-His-Phen and VO-His-bipy ternary systems in glycol/water(1:1) solution at various acidity have been observed at 173K. It was found that different structural complexes were formed depending on the pH value of the solution. Their possible structures were suggested according to Johnson's rule.
The ESR spectra of VO-His-Phen and VO-His-bipy ternary systems in glycol/water(1:1) solution at various acidity have been observed at 173K. It was found that different structural complexes were formed depending on the pH value of the solution. Their possible structures were suggested according to Johnson's rule.
1993, 10(3): 72-74
Abstract:
The rare earth in its mixture has been determined by 1H and 13C NMR in its aqueous halide solution. For samples containing only light lanthanides,both 1H and 13C spectrometry can be used for quantitative determination of individual rare earth in the mixture. For samples containing heavy lanthanides, 1H spectraometry is unsuitable for accurate determination due to the serious broadening and overlapping of the signals in the spectra and interference from water. 13C spectrometry,however,can be used successfully since each complex of Ln (NTA)2 in the mixture has at least a unique well-re-solved peak.
The rare earth in its mixture has been determined by 1H and 13C NMR in its aqueous halide solution. For samples containing only light lanthanides,both 1H and 13C spectrometry can be used for quantitative determination of individual rare earth in the mixture. For samples containing heavy lanthanides, 1H spectraometry is unsuitable for accurate determination due to the serious broadening and overlapping of the signals in the spectra and interference from water. 13C spectrometry,however,can be used successfully since each complex of Ln (NTA)2 in the mixture has at least a unique well-re-solved peak.
1993, 10(3): 75-76
Abstract:
A modified type of zeolite Fe-ZSM-5 was used as catalyst for the addition-esterification between carboxylic acids and epoxides. Eleven β-hydroxyl propyl carboxylates were catalytically prepared by Fe-ZSM-5 in yield of 69~89%.
A modified type of zeolite Fe-ZSM-5 was used as catalyst for the addition-esterification between carboxylic acids and epoxides. Eleven β-hydroxyl propyl carboxylates were catalytically prepared by Fe-ZSM-5 in yield of 69~89%.
1993, 10(3): 77-79
Abstract:
The moisture sensing characteristics of three kinds of compounds prepared by quaternized poly(γ-aminpropyltriethoxysilane) were examined. The results showed that the moisture sensors have the sensitivity>103(30%~90%RH), hysteresis<2%, response time<30s, good selectivity and reusability.
The moisture sensing characteristics of three kinds of compounds prepared by quaternized poly(γ-aminpropyltriethoxysilane) were examined. The results showed that the moisture sensors have the sensitivity>103(30%~90%RH), hysteresis<2%, response time<30s, good selectivity and reusability.
1993, 10(3): 80-82
Abstract:
The title complex[(t-BuCp)2GdCl]2 was synthesizedby reacting anhydrous GdCl3 with sodium tert-butylcyclopentadienide in THF. The complex was characterized by elemental analysis,infrared and 1H NMR spectroscopy. The crystal of the complex as determined by an X-ray diffraetometry belongs to orthorhombic with space group Cmca,unit cell parameters a=2.3397(3),b=0.9460 (5),c=1.6473(5)nm. V=3.646(2)nm2,Dc=1.58g/cm3,Z=4. The structure was refined by least-square technique to R=0.051 for 1027 observed reflections. The molecules exist as a chlorinebridged dimer,Gd-C10.2771(3)nm with tert-butylcyclopentadienyl groups being bonded in a pentahepto-fashion.
The title complex[(t-BuCp)2GdCl]2 was synthesizedby reacting anhydrous GdCl3 with sodium tert-butylcyclopentadienide in THF. The complex was characterized by elemental analysis,infrared and 1H NMR spectroscopy. The crystal of the complex as determined by an X-ray diffraetometry belongs to orthorhombic with space group Cmca,unit cell parameters a=2.3397(3),b=0.9460 (5),c=1.6473(5)nm. V=3.646(2)nm2,Dc=1.58g/cm3,Z=4. The structure was refined by least-square technique to R=0.051 for 1027 observed reflections. The molecules exist as a chlorinebridged dimer,Gd-C10.2771(3)nm with tert-butylcyclopentadienyl groups being bonded in a pentahepto-fashion.
1993, 10(3): 83-84
Abstract:
An efficient route for 4,4'-dihydroxybiphenyl synthesis has been developed. The diazotisation reaction is carried out with 25% sulfphuric acid. It occurs readily under mild conditions in satisfactory yield but less by-products.
An efficient route for 4,4'-dihydroxybiphenyl synthesis has been developed. The diazotisation reaction is carried out with 25% sulfphuric acid. It occurs readily under mild conditions in satisfactory yield but less by-products.
1993, 10(3): 85-87
Abstract:
The discharge characteristics of MLNi3.5MnCO0.4Al0.1(ML=mixed rare earths rich in lanthanum) hydrogen storage electrode were studied in the KOH solution of different concentration. The discharge capacity, fast discharge ability, selfdischarge rate of MH electrode were found to be improved by increasing the electrolyte concentration. The linear relationship between Ip and v1/2 values obtained from cyclic voltammetry curves indicated that the reactions at the electrode were controlled by diffusion process.
The discharge characteristics of MLNi3.5MnCO0.4Al0.1(ML=mixed rare earths rich in lanthanum) hydrogen storage electrode were studied in the KOH solution of different concentration. The discharge capacity, fast discharge ability, selfdischarge rate of MH electrode were found to be improved by increasing the electrolyte concentration. The linear relationship between Ip and v1/2 values obtained from cyclic voltammetry curves indicated that the reactions at the electrode were controlled by diffusion process.
1993, 10(3): 88-90
Abstract:
The heteropoly 12-tungstotitanates were prepared by H+ type ion exchange of K13[Ln (TiW11O39)2] or K6[MTiW11O39(Ln=lantanide and M=Mn2+,Cu2+,Zn2+). Their properties were determined by means of IR, UV, XPS, TG-DTA.
The heteropoly 12-tungstotitanates were prepared by H+ type ion exchange of K13[Ln (TiW11O39)2] or K6[MTiW11O39(Ln=lantanide and M=Mn2+,Cu2+,Zn2+). Their properties were determined by means of IR, UV, XPS, TG-DTA.
1993, 10(3): 91-93
Abstract:
The properties of polyisoprene bulk polymerized with rare-earth catalyst (Ln-IR) are reported. The Mooney viscosity(ML) values of Ln-IR are obviously higher than that of Ln-IR obtained in solution polymerization with the same[η]. Under certain polymerization conditions, some long branching chains may occur in the molecular structure of Ln-IR. The cis-1,4 content of Ln-IR was slightly lower than that of Ti-IR and NR, but the stress-strain property and viscoelasticity were basically the same as that of Ti-IR. The bulk Ln-IR showed a good fluidity at higher shear rate. The activation energy of viscous flow was about 11.0 kJ/mol, equal to that of Ti-IR, but slightly lower than that of NR.
The properties of polyisoprene bulk polymerized with rare-earth catalyst (Ln-IR) are reported. The Mooney viscosity(ML) values of Ln-IR are obviously higher than that of Ln-IR obtained in solution polymerization with the same[η]. Under certain polymerization conditions, some long branching chains may occur in the molecular structure of Ln-IR. The cis-1,4 content of Ln-IR was slightly lower than that of Ti-IR and NR, but the stress-strain property and viscoelasticity were basically the same as that of Ti-IR. The bulk Ln-IR showed a good fluidity at higher shear rate. The activation energy of viscous flow was about 11.0 kJ/mol, equal to that of Ti-IR, but slightly lower than that of NR.
1993, 10(3): 94-96
Abstract:
The title explosive has been synthesized in high yield. It is an orange yellow solid with density of 1.84g/cm3, temperature of decomposition 310℃(DTA) and detonation velocity 807.6m/s,and without weighloss at 100℃ for 48 hours.
The title explosive has been synthesized in high yield. It is an orange yellow solid with density of 1.84g/cm3, temperature of decomposition 310℃(DTA) and detonation velocity 807.6m/s,and without weighloss at 100℃ for 48 hours.
1993, 10(3): 97-99
Abstract:
A novel method for calculation of electronic polarizability of ions in crystals has been proposed based on the crystal structure, dielectric constant and ion radii of crystals. The results on the alkaline earth chaleogenides and alkali halides showed that the polarizability for the same ion is different in various crystals reflecting the interactions between ions in different crystals.
A novel method for calculation of electronic polarizability of ions in crystals has been proposed based on the crystal structure, dielectric constant and ion radii of crystals. The results on the alkaline earth chaleogenides and alkali halides showed that the polarizability for the same ion is different in various crystals reflecting the interactions between ions in different crystals.
1993, 10(3): 100-101
Abstract:
The extraction of Au (Ⅲ) with trioctylamine (TOA) in carbon tetrachloride from hydrochloride medium has been studied. The mechanism of the extraction is proposed as follows: AuCl4-+(m+1)TOAH+Cl(O)-
TOAH+AuCl4-·mOAH+Cl(O)-+Cl- where (O) represents the organic phase, m=0,1,and logK0=4.23, logK1=8.67.
The extraction of Au (Ⅲ) with trioctylamine (TOA) in carbon tetrachloride from hydrochloride medium has been studied. The mechanism of the extraction is proposed as follows: AuCl4-+(m+1)TOAH+Cl(O)-
TOAH+AuCl4-·mOAH+Cl(O)-+Cl- where (O) represents the organic phase, m=0,1,and logK0=4.23, logK1=8.67.
1993, 10(3): 102-104
Abstract:
The Raman and FT-IR spectra of a 30% aqueous solution of cetyltrimethylammonium bromide have been investigated. A transition from coagel to micelle phase was observed at 300K. In the coagel phase, the hydrocarbon molecules exist in the bent end-methyl TG conformation with a few kink GTG' forms. In the micellar phase, the number of GTG' conformers increases, and the gauchetrans-ganche(GTG) and the doublegauche (CG) conformers exist in considerable concentrations.
The Raman and FT-IR spectra of a 30% aqueous solution of cetyltrimethylammonium bromide have been investigated. A transition from coagel to micelle phase was observed at 300K. In the coagel phase, the hydrocarbon molecules exist in the bent end-methyl TG conformation with a few kink GTG' forms. In the micellar phase, the number of GTG' conformers increases, and the gauchetrans-ganche(GTG) and the doublegauche (CG) conformers exist in considerable concentrations.
1993, 10(3): 105-106
Abstract:
The N-alkylation of acetanilide has been carried out under the ultrasonic irradiation in the presence of phase transfer catalysts. The reaction conditions were mild and the yield of products was satisfactory.
The N-alkylation of acetanilide has been carried out under the ultrasonic irradiation in the presence of phase transfer catalysts. The reaction conditions were mild and the yield of products was satisfactory.
1993, 10(3): 107-109
Abstract:
The oscillation phenomena of electrical conductance of SnO2 polycrystal doped with Al2O3 and MgO have been observed at room temperature. The dependance of the oscillation upon the constitution of the surrounding atmosphere, e.g. concentration of O2, CO, C2H2, air as well as N2 is reported.
The oscillation phenomena of electrical conductance of SnO2 polycrystal doped with Al2O3 and MgO have been observed at room temperature. The dependance of the oscillation upon the constitution of the surrounding atmosphere, e.g. concentration of O2, CO, C2H2, air as well as N2 is reported.
1993, 10(3): 110-111
Abstract:
The thermal decomposition of urea in the crude KNCO has been studied by DTA and TG techniques. The kinetic parameters were ealeulated according to the obtained rate equations of thermal decomposition of urea. An improved technology has been proposed for the elemination of urea from KNCO.
The thermal decomposition of urea in the crude KNCO has been studied by DTA and TG techniques. The kinetic parameters were ealeulated according to the obtained rate equations of thermal decomposition of urea. An improved technology has been proposed for the elemination of urea from KNCO.
1993, 10(3): 112-113
Abstract:
A simple method for determination of the gel strength of the super water-absorbent is described. The relative error of the determination is ±2%.
A simple method for determination of the gel strength of the super water-absorbent is described. The relative error of the determination is ±2%.
1993, 10(3): 114-115
Abstract:
The inverse suspension polymerization of acrylamide has been carried out in the presence of emulsifier Span 20 and Span 80, and K2S2O8 as initiator. The polymerization rate Rp was found to be proportional to[M]0.13 and to [I]0.11, and the molecular weight of polymer Mw varied with[M]1.1 and[I]0.11 respectively. The overall activation energy for polymerization of aerylamide at 40~50℃ was calculeted to be 30.5 kJ/mol.
The inverse suspension polymerization of acrylamide has been carried out in the presence of emulsifier Span 20 and Span 80, and K2S2O8 as initiator. The polymerization rate Rp was found to be proportional to[M]0.13 and to [I]0.11, and the molecular weight of polymer Mw varied with[M]1.1 and[I]0.11 respectively. The overall activation energy for polymerization of aerylamide at 40~50℃ was calculeted to be 30.5 kJ/mol.
1993, 10(3): 116-117
Abstract:
The blends of phenophthalein polyether-ether-sulfone (PES-C) and phenophthalein polyether-ether-ketone (PEK-C) were prepared in a twin screw extruder. Both miscible and immiscible PES-C/PEK-C blends were obtained depending on the mixing conditions. The miscibility of the blends is discussed in terms of the solubility parameters and the glass transition temperatures.
The blends of phenophthalein polyether-ether-sulfone (PES-C) and phenophthalein polyether-ether-ketone (PEK-C) were prepared in a twin screw extruder. Both miscible and immiscible PES-C/PEK-C blends were obtained depending on the mixing conditions. The miscibility of the blends is discussed in terms of the solubility parameters and the glass transition temperatures.
