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2003 Volume 20 Issue 1
2003, 20(1): 1-5
Abstract:
The content of the hardener in the poly(dimethylsiloxane)(PDMS) system, which is usually used to make elastomeric stamp for "soft lithography", is optimized by using a resin curometer. It is found that when the the content of the hardener B is between 2.5%~3.0%, the PDMS system has the optimum curing rate and the best elastic property. Stamps made from the above PDMS system were used to make microstructures by "Micromolding in Capillaries(MIMIC)" technique. Reactions occurred between K2CO3 and CuSO4 in capillaries and crystallization in the limited spaces of capillary were observed. Microlines are produced from CuSO4 and sodium benzoate, also from polyamic acid and polyethylene glycol
The content of the hardener in the poly(dimethylsiloxane)(PDMS) system, which is usually used to make elastomeric stamp for "soft lithography", is optimized by using a resin curometer. It is found that when the the content of the hardener B is between 2.5%~3.0%, the PDMS system has the optimum curing rate and the best elastic property. Stamps made from the above PDMS system were used to make microstructures by "Micromolding in Capillaries(MIMIC)" technique. Reactions occurred between K2CO3 and CuSO4 in capillaries and crystallization in the limited spaces of capillary were observed. Microlines are produced from CuSO4 and sodium benzoate, also from polyamic acid and polyethylene glycol
2003, 20(1): 6-9
Abstract:
The effects of rare earth elements(RE) on the activities of seven enzyme (ALT, ICD, AST, LAP, ALP, γ-GT, CHE) in rat liver have been investigated by analysing the accumulated amount of RE in the rat liver by ICP-MS. The results indicate the occurrence of Hormesis effect on most enzymes studied and the dependence of Hormesis dose-response range on the type and character of the enzymes. No significant relationship was observed between dosage and the accumulation of RE in the rat liver.
The effects of rare earth elements(RE) on the activities of seven enzyme (ALT, ICD, AST, LAP, ALP, γ-GT, CHE) in rat liver have been investigated by analysing the accumulated amount of RE in the rat liver by ICP-MS. The results indicate the occurrence of Hormesis effect on most enzymes studied and the dependence of Hormesis dose-response range on the type and character of the enzymes. No significant relationship was observed between dosage and the accumulation of RE in the rat liver.
2003, 20(1): 10-14
Abstract:
Reacting the mixture of fine cobalt sulfate and ferrous sulfate with PEG-600 in NaOH solution(at pH=9.0) gave a precusor, CoFeO(OH)2O, which after immersion in (NH4O)2S2O8 solution, reacting, drying and calcinating at 500℃ afforded the title solid superacid S2O82-/CoFe2O4. The compound was characterized by XRD, TEM, BET, TG-DTA techniques and chemical analysis. The results show that S2O82-/CoFe2O4 was sized in 42 nm with specific surface area of 146 m2/g. The solid superacid S2O82-/CoFe2O4 was used as catalyst in synthesis of diethyl sebacate from absolute ethanol and sebacic acid. At the conditions of 1.0 g catalyst with the acid strength of -16.02< H0< -14.52, 0.1 mol sebacic acid, molar ratio of absolute ehtanol to sebacic acid 4.0:1.0, and reaction time of 2.5 h, diethyl sebacate in yield of 93.6% was obtained.
Reacting the mixture of fine cobalt sulfate and ferrous sulfate with PEG-600 in NaOH solution(at pH=9.0) gave a precusor, CoFeO(OH)2O, which after immersion in (NH4O)2S2O8 solution, reacting, drying and calcinating at 500℃ afforded the title solid superacid S2O82-/CoFe2O4. The compound was characterized by XRD, TEM, BET, TG-DTA techniques and chemical analysis. The results show that S2O82-/CoFe2O4 was sized in 42 nm with specific surface area of 146 m2/g. The solid superacid S2O82-/CoFe2O4 was used as catalyst in synthesis of diethyl sebacate from absolute ethanol and sebacic acid. At the conditions of 1.0 g catalyst with the acid strength of -16.02< H0< -14.52, 0.1 mol sebacic acid, molar ratio of absolute ehtanol to sebacic acid 4.0:1.0, and reaction time of 2.5 h, diethyl sebacate in yield of 93.6% was obtained.
2003, 20(1): 15-18
Abstract:
A new type of Schiff-base porphyrin polymer with network nanostructure was synthesized using tetra(4-aminophenyl) porphyrin(TAPP) as matrix and glutaraldehyde as a bridging compound. The reaction mixture was refluxed in a Soxlet extractor until the eluents became colorless. The UV spectral bands of the chloroform extracts and N,N-dimethylformamide extract have 3~5 nm blue shifts as compared to that of the TAPP. Compared with the TAPP, a new absorbance band at 1687 cm-1 was observed in the infrared spectrum of the product owing to C=N contractive vibration. The polymerization degree of the Schiff-base porphyrin was estimated to be 15 by quantitative infrared-analysis of the absorbance ratio of the end groups in the polymer and the monomer. The TEM results indicated that the porphyrin polymer has network structure with an average distance of 4.1 nm between porphyrin molecules, close to the estimated bond length(3.9 nm).
A new type of Schiff-base porphyrin polymer with network nanostructure was synthesized using tetra(4-aminophenyl) porphyrin(TAPP) as matrix and glutaraldehyde as a bridging compound. The reaction mixture was refluxed in a Soxlet extractor until the eluents became colorless. The UV spectral bands of the chloroform extracts and N,N-dimethylformamide extract have 3~5 nm blue shifts as compared to that of the TAPP. Compared with the TAPP, a new absorbance band at 1687 cm-1 was observed in the infrared spectrum of the product owing to C=N contractive vibration. The polymerization degree of the Schiff-base porphyrin was estimated to be 15 by quantitative infrared-analysis of the absorbance ratio of the end groups in the polymer and the monomer. The TEM results indicated that the porphyrin polymer has network structure with an average distance of 4.1 nm between porphyrin molecules, close to the estimated bond length(3.9 nm).
2003, 20(1): 19-22
Abstract:
An improved method was used to prepare mercurochrome-sensitized TiO2 photoelectrode. The transient photocurrent of the electrode at different bias and I-V curves of the photochemical cell with the electrode were measured. The results showed that the short photocurrent on the novel electrode increased by 70% and the open voltage increased by 17% compared to that on the electrode prepared by conventional method.
An improved method was used to prepare mercurochrome-sensitized TiO2 photoelectrode. The transient photocurrent of the electrode at different bias and I-V curves of the photochemical cell with the electrode were measured. The results showed that the short photocurrent on the novel electrode increased by 70% and the open voltage increased by 17% compared to that on the electrode prepared by conventional method.
2003, 20(1): 23-28
Abstract:
The n-p coupled semiconductor materials Cu/TiO2-NiO were prepared by a sol-gel method, TG-DTA, TPR, as well as XRD, TEM and UV-Vis were used to characterize the crystal structure and photo absorbing ability of the precurors and final catalysts, respectively. The Photo Stimulated Surface Reaction(PSSR) of CO2 and H2O on Cu/TiO2-NiO has been investigated. The results revealed that CH3OH, CH4 and CO can be produced by PSSR at normal temperature with high selectivity of CH3OH. The composition of the material shows significant effects on the PSSR. The highest CO2 conversion was obtained on 0.50% Cu/TiO2-2.0% NiO catalyst.
The n-p coupled semiconductor materials Cu/TiO2-NiO were prepared by a sol-gel method, TG-DTA, TPR, as well as XRD, TEM and UV-Vis were used to characterize the crystal structure and photo absorbing ability of the precurors and final catalysts, respectively. The Photo Stimulated Surface Reaction(PSSR) of CO2 and H2O on Cu/TiO2-NiO has been investigated. The results revealed that CH3OH, CH4 and CO can be produced by PSSR at normal temperature with high selectivity of CH3OH. The composition of the material shows significant effects on the PSSR. The highest CO2 conversion was obtained on 0.50% Cu/TiO2-2.0% NiO catalyst.
2003, 20(1): 29-33
Abstract:
Poly(vinylidene fluoride)(PVDF) has been modified by free radical chlorination. The effects of reaction conditions on chlorination degree, including chlorine gas flow rate, initiator concentration, dispersing medium, reaction temperature and time were investigated. The chlorinated PVDF was characterized by chemical titration and 1H NMR. Its solubility, adhesivity, softening point, contact angle and thermal property were measured. The results show that the chlorination degree of PVDF could be controlled in the range of 1%~16.3%. With the increase of chlorination degree the melting point of PVDF decreased from 163℃ to 130℃; the contact angle with H2O decreased from 90° to 54°. The polymers containing more than 6% chlorine were soluble in acetone. The solubility parameters to methanol and tetrachloro-methane were changed. The chlorinated PVDF appeared to be less stable than PVDF, but its decomposion temperature was yet above 300℃.
Poly(vinylidene fluoride)(PVDF) has been modified by free radical chlorination. The effects of reaction conditions on chlorination degree, including chlorine gas flow rate, initiator concentration, dispersing medium, reaction temperature and time were investigated. The chlorinated PVDF was characterized by chemical titration and 1H NMR. Its solubility, adhesivity, softening point, contact angle and thermal property were measured. The results show that the chlorination degree of PVDF could be controlled in the range of 1%~16.3%. With the increase of chlorination degree the melting point of PVDF decreased from 163℃ to 130℃; the contact angle with H2O decreased from 90° to 54°. The polymers containing more than 6% chlorine were soluble in acetone. The solubility parameters to methanol and tetrachloro-methane were changed. The chlorinated PVDF appeared to be less stable than PVDF, but its decomposion temperature was yet above 300℃.
2003, 20(1): 34-37
Abstract:
Rhodamine B(RhB) produces a single scanning polarographic wave at -0.59 V in a 10 mmol/L H2SO4 solution. In the presence of PdI42-, RhB+ combining with it produces a hydrophobic associacid molecule PdI4-2RhB via static attraction. By means of hydrophobic force and Van der Waal's force, this associated molecules form (PdI4-2RhB)n associated nanoparticles in violet-red color, in size of about 20 nm. The nanoparticles exhibit a synchronous scattering peak at 470 nm and a characteristic resonance scattering peak at 520 nm, and the polarographic wave at -0.59 V is quenched. When organic solvents such as alcohols and acetone is added into the nanoparticle system, the (PdI4-2RhB)n nanoparticles are decomposed into PdI4-2RhB molecules, and the two mentioned scattering peaks disappear, the polarographic wave and the synchronous fluorescence peak increase, and the color of the system reduces to red. The results demonstrate that the formation of (PdI4-2RhB)n associated nanoparticles caures the polarographic quenching effect and resonance scattering effect.
Rhodamine B(RhB) produces a single scanning polarographic wave at -0.59 V in a 10 mmol/L H2SO4 solution. In the presence of PdI42-, RhB+ combining with it produces a hydrophobic associacid molecule PdI4-2RhB via static attraction. By means of hydrophobic force and Van der Waal's force, this associated molecules form (PdI4-2RhB)n associated nanoparticles in violet-red color, in size of about 20 nm. The nanoparticles exhibit a synchronous scattering peak at 470 nm and a characteristic resonance scattering peak at 520 nm, and the polarographic wave at -0.59 V is quenched. When organic solvents such as alcohols and acetone is added into the nanoparticle system, the (PdI4-2RhB)n nanoparticles are decomposed into PdI4-2RhB molecules, and the two mentioned scattering peaks disappear, the polarographic wave and the synchronous fluorescence peak increase, and the color of the system reduces to red. The results demonstrate that the formation of (PdI4-2RhB)n associated nanoparticles caures the polarographic quenching effect and resonance scattering effect.
2003, 20(1): 38-41
Abstract:
UV-vis spectrophotometric titration was used to calculate the stability constants of an inclusion complex of β-cyclodextrins(β-CD) with chlorambucil(CHL) in different pH buffer solutions at 10℃. The stoichiometry of the inclusion complexes appeared to be 1:1. It was found that there is a stronger inclusion effection in pH=4 buffer solution. Two solid inclusion complexes were obtained with different preparation conditions. The results of DSC and powder X-ray diffraction measurements indicated that novel crystalline structures of inclusion complex were formed under two different conditions. TLC was used to analyze the components of the solid complexes. The results indicated that the hydrolysis of CHL can be efficiently avoided under the low temperature using mixture solvent of alcoholate and water.
UV-vis spectrophotometric titration was used to calculate the stability constants of an inclusion complex of β-cyclodextrins(β-CD) with chlorambucil(CHL) in different pH buffer solutions at 10℃. The stoichiometry of the inclusion complexes appeared to be 1:1. It was found that there is a stronger inclusion effection in pH=4 buffer solution. Two solid inclusion complexes were obtained with different preparation conditions. The results of DSC and powder X-ray diffraction measurements indicated that novel crystalline structures of inclusion complex were formed under two different conditions. TLC was used to analyze the components of the solid complexes. The results indicated that the hydrolysis of CHL can be efficiently avoided under the low temperature using mixture solvent of alcoholate and water.
2003, 20(1): 42-46
Abstract:
The rheological behavior of the suspension consisted of alumimum-magnesium hydrotalcite-like compounds(Al-Mg-HTlc) with permanent positive charge and Na-montmorillonite(Na-MT) with permanent negative charge have been studied as function of the applicability of the Bingham rheological equation and the Brinkman viscosity equation. The influences of Al-Mg-HTlc/MT mass ratio(R) on apparent viscosity(ηA), Bingham yield stress(τB) and E-B coefficient(K) were also investigated. The results show that the suspension with ω(MT)=1.5% and the Al-Mg-HTlc/MT suspension with the same MT, contnet and R=0.2 belong to Newtonian fluid; the pure MT suspension with ω(MT)≥3% and the Al-Mg-HTlc/MT suspension with ω(MT)≥3% belong to pseudoplastic fluid. The pure MT suspension conforms to the Bingham rheological equation, whereas the Al-Mg-HTlc/MT suspension conforms to the Bingham equation only at high shear rate (D=300~1100 s-1). Both the pure MT suspension and Al-Mg-HTlc/MT suspensions conform to the Brinkman viscosity equation in the range of 0~1022 s-1 shear rate. All the ηA, τB and K values were found increased with increase in R and went through a maximum at R around 0.25. The mechanism of interaction between the particles and the characteristic parameters were discussed. It is concluded that the E-B coefficient K of the Brinkman viscosity equation is the ‘Intrinsic Rheological Parameter’, characteristic of the internal interaction among the particles of the system.
The rheological behavior of the suspension consisted of alumimum-magnesium hydrotalcite-like compounds(Al-Mg-HTlc) with permanent positive charge and Na-montmorillonite(Na-MT) with permanent negative charge have been studied as function of the applicability of the Bingham rheological equation and the Brinkman viscosity equation. The influences of Al-Mg-HTlc/MT mass ratio(R) on apparent viscosity(ηA), Bingham yield stress(τB) and E-B coefficient(K) were also investigated. The results show that the suspension with ω(MT)=1.5% and the Al-Mg-HTlc/MT suspension with the same MT, contnet and R=0.2 belong to Newtonian fluid; the pure MT suspension with ω(MT)≥3% and the Al-Mg-HTlc/MT suspension with ω(MT)≥3% belong to pseudoplastic fluid. The pure MT suspension conforms to the Bingham rheological equation, whereas the Al-Mg-HTlc/MT suspension conforms to the Bingham equation only at high shear rate (D=300~1100 s-1). Both the pure MT suspension and Al-Mg-HTlc/MT suspensions conform to the Brinkman viscosity equation in the range of 0~1022 s-1 shear rate. All the ηA, τB and K values were found increased with increase in R and went through a maximum at R around 0.25. The mechanism of interaction between the particles and the characteristic parameters were discussed. It is concluded that the E-B coefficient K of the Brinkman viscosity equation is the ‘Intrinsic Rheological Parameter’, characteristic of the internal interaction among the particles of the system.
2003, 20(1): 47-50
Abstract:
Polydiallyldimethylammonium chloride(PDMDAAC), annular and stable to heat and base, could act as a more effective phase-transfer catalyst than cetyltrimethylammonium bromide or polymer-grafted quaternary phosphonium or pyridinium salts in halogen exchange reaction. In the presence of this water-soluble polymer, with an average molecular weight of some 2×105 g/mol, p-fluoronitrobenzene was prepared from p-chloronitrobenzene in yield of 92.5%. Microwave irradiation accelerated the reaction for about 3 times in comparison with common heating process probably due to the "non-thermal effect" of microwave to chemical reaction.
Polydiallyldimethylammonium chloride(PDMDAAC), annular and stable to heat and base, could act as a more effective phase-transfer catalyst than cetyltrimethylammonium bromide or polymer-grafted quaternary phosphonium or pyridinium salts in halogen exchange reaction. In the presence of this water-soluble polymer, with an average molecular weight of some 2×105 g/mol, p-fluoronitrobenzene was prepared from p-chloronitrobenzene in yield of 92.5%. Microwave irradiation accelerated the reaction for about 3 times in comparison with common heating process probably due to the "non-thermal effect" of microwave to chemical reaction.
2003, 20(1): 51-54
Abstract:
Polyethersulfone(PES) ultrafitration membranes were prepared by a phase-inversion method. The water flux and the rejection of the membranes for vitamin B12 were measured and their top layer and cross section morphology were observed by SEM. The formation of macrovoids in the sublayer of the membranes, effects of polyethersulfone mass fraction in the casting solution, as well as the presence of phosphoric acid on the structure of sublayer and property of the final membranes had been investigated. It was found that formation of top layer had a significant effect on the structure of the sublayer of membrance. The appropriate PES mass fraction appeared in between 12% and 18%. Morphology of top layer, structure of sublayer and property of the membranes could be controlled by addition of a small amount of phosphoric acid to the casting solution.
Polyethersulfone(PES) ultrafitration membranes were prepared by a phase-inversion method. The water flux and the rejection of the membranes for vitamin B12 were measured and their top layer and cross section morphology were observed by SEM. The formation of macrovoids in the sublayer of the membranes, effects of polyethersulfone mass fraction in the casting solution, as well as the presence of phosphoric acid on the structure of sublayer and property of the final membranes had been investigated. It was found that formation of top layer had a significant effect on the structure of the sublayer of membrance. The appropriate PES mass fraction appeared in between 12% and 18%. Morphology of top layer, structure of sublayer and property of the membranes could be controlled by addition of a small amount of phosphoric acid to the casting solution.
2003, 20(1): 55-58
Abstract:
The Fe-Ni mixed oxide catalyst was synthesized by solid state reaction under microwave irradiation. The structure of the catalyst was characterized by TG-DTA, XRD, TEM, IR and TPR methods. The results show that the product is spinel-type nanoparticle with size of 11 nm. The mixed oxide catalyst had high activity in oxidative dehydrogenation of ethylbenzene to styrene by carbon dioxide.
The Fe-Ni mixed oxide catalyst was synthesized by solid state reaction under microwave irradiation. The structure of the catalyst was characterized by TG-DTA, XRD, TEM, IR and TPR methods. The results show that the product is spinel-type nanoparticle with size of 11 nm. The mixed oxide catalyst had high activity in oxidative dehydrogenation of ethylbenzene to styrene by carbon dioxide.
2003, 20(1): 59-64
Abstract:
Two series of α-methyl biphenyl esters, series PBM and series PMB including tweleve compounds were synthesized. All these compounds are liquid crystals with low melting points due to the α-methyl stereo-effect. There are very wide smectic C(Sc) or chiral smectic C(Sc*) liquid crystal phase ranges in the PBM series compounds, but narrow phase ranges in the PMB series where the α-methyl is in the central part of the molecular chain. The chemical structures of the compounds were verfied by IR, 1H NMR, MS spectra and elemental analysis. Their transition temperatures of liquid crystal phase and phase states were verified by DSC and POM. They could have promising applications especially as components in the ferroelectric liquid crystal display.
Two series of α-methyl biphenyl esters, series PBM and series PMB including tweleve compounds were synthesized. All these compounds are liquid crystals with low melting points due to the α-methyl stereo-effect. There are very wide smectic C(Sc) or chiral smectic C(Sc*) liquid crystal phase ranges in the PBM series compounds, but narrow phase ranges in the PMB series where the α-methyl is in the central part of the molecular chain. The chemical structures of the compounds were verfied by IR, 1H NMR, MS spectra and elemental analysis. Their transition temperatures of liquid crystal phase and phase states were verified by DSC and POM. They could have promising applications especially as components in the ferroelectric liquid crystal display.
2003, 20(1): 65-68
Abstract:
Polylactic acid(PLA) microspheres(MS) were prepared by an oil-in-water solvent evaporation method to encapsulate rifampin(RFP). Effects of molecular weight of PLA, the drug content, microsphere size, pH value of medium on the drug-releasing performance of the PLA microspheres were investigated. The results showed that the greater the molecular weight of PLA, the less it degrades and the more slowly the drug release. Again, the greater the content of RFP and the greater the difference of drug concentration between in and out of the microsphere, the more quickly the drug releases. The smaller the microsphere size, the more quickly the drug releases. In the alkali medium, the PLA degrades more quickly, and RFP becomes more stable, resulting in the faster release of drug.
Polylactic acid(PLA) microspheres(MS) were prepared by an oil-in-water solvent evaporation method to encapsulate rifampin(RFP). Effects of molecular weight of PLA, the drug content, microsphere size, pH value of medium on the drug-releasing performance of the PLA microspheres were investigated. The results showed that the greater the molecular weight of PLA, the less it degrades and the more slowly the drug release. Again, the greater the content of RFP and the greater the difference of drug concentration between in and out of the microsphere, the more quickly the drug releases. The smaller the microsphere size, the more quickly the drug releases. In the alkali medium, the PLA degrades more quickly, and RFP becomes more stable, resulting in the faster release of drug.
2003, 20(1): 69-72
Abstract:
The LiNixCo1-xO2 powder was synthesized by sintering spherical Ni(OH)2, LiNO3 and CoO in air at 800℃ for 8 h. XRD results showed that the powders are highly crystallized LiNixCo1-xO2 with ordered layer structure of α-NaFeO2. SEM microphotos showed the powders are spherical particulate with the particle size of ca. 7 μm. Electrochemical test proves. The discharge capacity of the cathode material was 152 mA·h/g and the capacity holding rate was 80% after 100 cycles. The cathode material has excellent electrochemical performance.
The LiNixCo1-xO2 powder was synthesized by sintering spherical Ni(OH)2, LiNO3 and CoO in air at 800℃ for 8 h. XRD results showed that the powders are highly crystallized LiNixCo1-xO2 with ordered layer structure of α-NaFeO2. SEM microphotos showed the powders are spherical particulate with the particle size of ca. 7 μm. Electrochemical test proves. The discharge capacity of the cathode material was 152 mA·h/g and the capacity holding rate was 80% after 100 cycles. The cathode material has excellent electrochemical performance.
2003, 20(1): 73-76
Abstract:
The iron-doped TiO2 nanoparticles in size of 60~70 nm were prepared by a sol-gel method, followed by freeze-drying treatment for 2 h. TG-DTA, XRD, UV-Vis, LDRSA and SEM observation and techniques were used to characterize the ultrafine particles. The presence of iron ion in TiO2 crystalline was found to increase the photocatalytic activity of TiO2 in degradation of phenol. The iron-doped TiO2 with different mass percentage of Fe3+ were compared with pure TiO2 when being used as photocatalyst in degradation of phenol. The best catalytic activity was observed in TiO2 with 0.05% doped Fe3+.
The iron-doped TiO2 nanoparticles in size of 60~70 nm were prepared by a sol-gel method, followed by freeze-drying treatment for 2 h. TG-DTA, XRD, UV-Vis, LDRSA and SEM observation and techniques were used to characterize the ultrafine particles. The presence of iron ion in TiO2 crystalline was found to increase the photocatalytic activity of TiO2 in degradation of phenol. The iron-doped TiO2 with different mass percentage of Fe3+ were compared with pure TiO2 when being used as photocatalyst in degradation of phenol. The best catalytic activity was observed in TiO2 with 0.05% doped Fe3+.
2003, 20(1): 77-79
Abstract:
Seven N-(pyridin-2-yl-carbonyl) aryl sulfonamides were synthesized from aryl sulfonamides and pyridin-2-yl-carboxylic acid, and their structures were confirmed by elemental analysis and 1H NMR. Some of the title compounds showed moderate herbicidal activity.
Seven N-(pyridin-2-yl-carbonyl) aryl sulfonamides were synthesized from aryl sulfonamides and pyridin-2-yl-carboxylic acid, and their structures were confirmed by elemental analysis and 1H NMR. Some of the title compounds showed moderate herbicidal activity.
2003, 20(1): 80-82
Abstract:
Title thioureas have been synthesized by reaction of substituted phenylamines with 1,4-or 1,3-benzenedicarbonyl chloride and ammonium thiocyanate by solid-liquid phase transfer catalysis using polyethylene glycol-400(PEG-400) as a catalyst in yield of 80%~96%. The compounds were characterized and identified by elemental analysis, IR and 1H NMR.
Title thioureas have been synthesized by reaction of substituted phenylamines with 1,4-or 1,3-benzenedicarbonyl chloride and ammonium thiocyanate by solid-liquid phase transfer catalysis using polyethylene glycol-400(PEG-400) as a catalyst in yield of 80%~96%. The compounds were characterized and identified by elemental analysis, IR and 1H NMR.
2003, 20(1): 83-85
Abstract:
Alizarin red S(ARS) causes a sharp incision in 0.1 mol/L KBr. In the presence of Zn2+, the incision depth of ARS decreased and a new incision of Zn-ARS coordination compound appeared. A second order differential simple oscillographic voltammetric method for determination of Zn2+ was developed. The method is applied to the determination of zinc gluconate in tablet. The linear range of Zn2+ was 2.0×10-7~8.6×10-6 mol/L,detection limit 1×10-7 mol/L, and RSD for determinations of 4.2×10-6 mol/L Zn2+ (n=7) was 2.4%.
Alizarin red S(ARS) causes a sharp incision in 0.1 mol/L KBr. In the presence of Zn2+, the incision depth of ARS decreased and a new incision of Zn-ARS coordination compound appeared. A second order differential simple oscillographic voltammetric method for determination of Zn2+ was developed. The method is applied to the determination of zinc gluconate in tablet. The linear range of Zn2+ was 2.0×10-7~8.6×10-6 mol/L,detection limit 1×10-7 mol/L, and RSD for determinations of 4.2×10-6 mol/L Zn2+ (n=7) was 2.4%.
2003, 20(1): 86-88
Abstract:
The raw heavy alkylbenzenes were fractionately separated into different fractions, from which five fractions with low, middle and high average molecular weight were collected and sulfonted by ClSO3H into corresponding heavy alkylbenzene sulfonates(HABS). Their synergetic effects on the interfacial tensions of Sichang(Daqing Oilfield) oil-water have been investigated. The interfacial activity of the mixed HABS of different molecular weight has been remarkably improved in comparison with that of single HABS.
The raw heavy alkylbenzenes were fractionately separated into different fractions, from which five fractions with low, middle and high average molecular weight were collected and sulfonted by ClSO3H into corresponding heavy alkylbenzene sulfonates(HABS). Their synergetic effects on the interfacial tensions of Sichang(Daqing Oilfield) oil-water have been investigated. The interfacial activity of the mixed HABS of different molecular weight has been remarkably improved in comparison with that of single HABS.
2003, 20(1): 89-91
Abstract:
The Knoevenagel reaction of aromatic aldehydes with malononitrile and ethyl cyanoacetate proceeds smoothly in the presence of carboxymethyl cellulose supported triethylenetetramine as catalyst in the 95% ethanol to afford the desired E-isomers of the corresponding alkenes in yield of 74%~96% and good purity. The results confirm that the catalyst can offer definite advantages of good activity, easy separation, mild reaction condition and high yields. Moreover, it can be reused for not less than 5 runs.
The Knoevenagel reaction of aromatic aldehydes with malononitrile and ethyl cyanoacetate proceeds smoothly in the presence of carboxymethyl cellulose supported triethylenetetramine as catalyst in the 95% ethanol to afford the desired E-isomers of the corresponding alkenes in yield of 74%~96% and good purity. The results confirm that the catalyst can offer definite advantages of good activity, easy separation, mild reaction condition and high yields. Moreover, it can be reused for not less than 5 runs.
2003, 20(1): 92-94
Abstract:
The polystyrene(PS) microspheres were prepared from free radical polymerization of styrene by a sol-gel method combined with centrifugal sedimentation. And the ordered macroporous titania was prepared from Ti(BuO)4 in ethanol solution using the mentioned PS microspheres as a template, which was removed from titania by calcination at 450℃. SEM images revealed the PS template has a three-dimentional ordered structure with particle diameter of ca. 450 nm and the macroporous titania thus obtained has a pore size of ca. 300 nm. XRD showed the macroporous titania has anatase structure.
The polystyrene(PS) microspheres were prepared from free radical polymerization of styrene by a sol-gel method combined with centrifugal sedimentation. And the ordered macroporous titania was prepared from Ti(BuO)4 in ethanol solution using the mentioned PS microspheres as a template, which was removed from titania by calcination at 450℃. SEM images revealed the PS template has a three-dimentional ordered structure with particle diameter of ca. 450 nm and the macroporous titania thus obtained has a pore size of ca. 300 nm. XRD showed the macroporous titania has anatase structure.
2003, 20(1): 95-97
Abstract:
3,4,5-Trimethoxybenzoyloxysolanesylamide(8) was first synthesized from solanesol in four steps. Thus, solanesyl bromide(5) prepared by the reaction of solanesol(4) and PBr3 was reacted with potassium phthalimide to give N-solanesylphthalimide(6), which was refluxed with N2H4·H2O in 95% EtOH to give solanesylamine(7). Compound 7 was then reacted with 3,4,5-trimethoxybenzoyloxyl chloride to give the title compound. Its structure has been confirmed by IR, 1H NMR, MS and elemental analysis.
3,4,5-Trimethoxybenzoyloxysolanesylamide(8) was first synthesized from solanesol in four steps. Thus, solanesyl bromide(5) prepared by the reaction of solanesol(4) and PBr3 was reacted with potassium phthalimide to give N-solanesylphthalimide(6), which was refluxed with N2H4·H2O in 95% EtOH to give solanesylamine(7). Compound 7 was then reacted with 3,4,5-trimethoxybenzoyloxyl chloride to give the title compound. Its structure has been confirmed by IR, 1H NMR, MS and elemental analysis.
2003, 20(1): 98-99
Abstract:
The synthesis of the title compound was carried out by the zinc dust reduction of 4-(4-methylphenoxy)benzaldoxime, which was obtained from commercially available p-bromobezaldehyde by reaction with potassium p-methylphenoxide. The method has the advantages of cheapness and high yield, without necessity of using toxic cyanide and handling of toxic organic cyanide.
The synthesis of the title compound was carried out by the zinc dust reduction of 4-(4-methylphenoxy)benzaldoxime, which was obtained from commercially available p-bromobezaldehyde by reaction with potassium p-methylphenoxide. The method has the advantages of cheapness and high yield, without necessity of using toxic cyanide and handling of toxic organic cyanide.
2003, 20(1): 100-102
Abstract:
A facile reaction of aryl Grignard reagents with 4-alkylacetophenones under ultrasonic irradiation is reported. The reaction can be completed within two minutes with a conversion of 15%~95% and gives 1,1-diarylethene and tertiary alcohol in the selectivity over 60%~96%(sometimes with 94.4% 1,1-diarylethene).
A facile reaction of aryl Grignard reagents with 4-alkylacetophenones under ultrasonic irradiation is reported. The reaction can be completed within two minutes with a conversion of 15%~95% and gives 1,1-diarylethene and tertiary alcohol in the selectivity over 60%~96%(sometimes with 94.4% 1,1-diarylethene).
