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1994 Volume 11 Issue 3
1994, 11(3): 1-10
Abstract:
The types,mechanisms,materials and applications of the controlled release of drugs,especially the use of polymeric material are briefly reviewed.
The types,mechanisms,materials and applications of the controlled release of drugs,especially the use of polymeric material are briefly reviewed.
1994, 11(3): 2-61
Abstract:
The distribution equilibria of La (Ⅲ) between aqueous nitrate solution and HDEHP in the presence of various diltuents have been studied at 298K,The extraction equilibrium constants decrease in the following order of diluents:n-hexane,cyclohexane,carbon tetrachloride,toluene,chloroform,methyl isobutyl ketone.Diluent effect on the equilibrium constants is discussed.
The distribution equilibria of La (Ⅲ) between aqueous nitrate solution and HDEHP in the presence of various diltuents have been studied at 298K,The extraction equilibrium constants decrease in the following order of diluents:n-hexane,cyclohexane,carbon tetrachloride,toluene,chloroform,methyl isobutyl ketone.Diluent effect on the equilibrium constants is discussed.
1994, 11(3): 11-15
Abstract:
Nine novel bicopper complexes of N,N,N',N",N"-pentabenzimidazolylmethyl diethylenetriamine were synthesized and characterized by IR,UV-vis,ESR and magneticsusceptibity measurements.Their catecholase and bioactivities were measured.There appeared an antiferromagnetic exchange interaction between copper ions within the complexes.The coordination bond Cu-N was partially covanlent.It was found for the first time that the compounds containing benzimidazole ligand haveantitumer activities in vitro and herbicidal and fungicidal activities as well.
Nine novel bicopper complexes of N,N,N',N",N"-pentabenzimidazolylmethyl diethylenetriamine were synthesized and characterized by IR,UV-vis,ESR and magneticsusceptibity measurements.Their catecholase and bioactivities were measured.There appeared an antiferromagnetic exchange interaction between copper ions within the complexes.The coordination bond Cu-N was partially covanlent.It was found for the first time that the compounds containing benzimidazole ligand haveantitumer activities in vitro and herbicidal and fungicidal activities as well.
1994, 11(3): 16-20
Abstract:
The ultrafiltration membranes have been prepared by the phase inversion method from polyphenylquinoxaline (PPQ) containing 4,4'-biphenylene group in the main chain.The effects of heat-treatment temperattire,time and polymer concentration on the performance of the membranes have been studied.Study of thermal stability and hydrolytic stability properties of membranes was carried out in glycerol bath at 120℃ for 10h,in water at 100℃ for 200h,using the pure water flux and the retention of bovine serum albumin (BSA) and chymotrypsinum (CMP) for judgement.The results showed that the membranes exhibited a better permeability,high selectivity,good thermal stability,hydrolytic stability,and tensile strength.
The ultrafiltration membranes have been prepared by the phase inversion method from polyphenylquinoxaline (PPQ) containing 4,4'-biphenylene group in the main chain.The effects of heat-treatment temperattire,time and polymer concentration on the performance of the membranes have been studied.Study of thermal stability and hydrolytic stability properties of membranes was carried out in glycerol bath at 120℃ for 10h,in water at 100℃ for 200h,using the pure water flux and the retention of bovine serum albumin (BSA) and chymotrypsinum (CMP) for judgement.The results showed that the membranes exhibited a better permeability,high selectivity,good thermal stability,hydrolytic stability,and tensile strength.
1994, 11(3): 21-25
Abstract:
The crystal structure of silicalite-Ⅰ zeolite could be improved by acid and/or hydrothermal treatments.The adsorption selectivity as well as the separation factor for ethanol-water mixture were found to be increased by such a treatment.Especially,the silicalite-Ⅰ obtained after successive acid and hydrothermal treatments filled polydimethyl-siloxane rubber membranes showed a separation factor for ethanol-water mixture up to 30.
The crystal structure of silicalite-Ⅰ zeolite could be improved by acid and/or hydrothermal treatments.The adsorption selectivity as well as the separation factor for ethanol-water mixture were found to be increased by such a treatment.Especially,the silicalite-Ⅰ obtained after successive acid and hydrothermal treatments filled polydimethyl-siloxane rubber membranes showed a separation factor for ethanol-water mixture up to 30.
1994, 11(3): 26-31
Abstract:
The kinetics equations for dissolution of carnallite and crystallization of KCl in mixed solutions of MgCl2 and KCl have been obtained.The mechanism of dissolution of car-nallite at 15~45℃ has been discussed.
The kinetics equations for dissolution of carnallite and crystallization of KCl in mixed solutions of MgCl2 and KCl have been obtained.The mechanism of dissolution of car-nallite at 15~45℃ has been discussed.
1994, 11(3): 32-35
Abstract:
The composite oxide NiCo2O4 prepared by aikali dipping and thermodecomposition showed a higher oxygen evolution activity in alkaline solution,The influences of preparation conditions on the oxygen evolution activity of NiCo2O4 were studied.
The composite oxide NiCo2O4 prepared by aikali dipping and thermodecomposition showed a higher oxygen evolution activity in alkaline solution,The influences of preparation conditions on the oxygen evolution activity of NiCo2O4 were studied.
1994, 11(3): 36-39
Abstract:
The strtictures and phase transitions of thermotropic liquid crystalline aromatic copolyesters based on p-hydroxy-benzoic acid (PHB),terephthalic acid (TPA) and bisphenol A (BPA) were studied by DSC,WAXD,and hot stage polarized microscopy.The effects of annealing and shearing on the microstructures and seqtience structures of the copolyesters were discussed emphatically,The two glass transition temperatures occurred in sample with 50% PHB bave been discussed.
The strtictures and phase transitions of thermotropic liquid crystalline aromatic copolyesters based on p-hydroxy-benzoic acid (PHB),terephthalic acid (TPA) and bisphenol A (BPA) were studied by DSC,WAXD,and hot stage polarized microscopy.The effects of annealing and shearing on the microstructures and seqtience structures of the copolyesters were discussed emphatically,The two glass transition temperatures occurred in sample with 50% PHB bave been discussed.
1994, 11(3): 40-44
Abstract:
A series of solid soItition Pr2-xSrxNiO4(0.00≤x≤1.00) were synthesized with the nickel valence being +2 to +3.The mixed oxides crystallized in orthorhombic (0.00≤x<0.10 and x=1.00) or tetragonal system (0.10≤x<1.00).The crystal parameter ratio c/a shows a maximum at x=0.5 caused by Jahn-Teller distortion in octahedral site of the low-spin Ni3+ ions.The magnetic susceptibilities of the mixed oxides follow the Curie-Weiss rule at temperatures 77~250K.An antiferomagne exchange interaction was observed in all the samples.The change of electrical properties in the system of x>0.5 is attributed to the change of electronic configuration of Ni3+ from t2g6dZ21 to t2g6dx2-y21.
A series of solid soItition Pr2-xSrxNiO4(0.00≤x≤1.00) were synthesized with the nickel valence being +2 to +3.The mixed oxides crystallized in orthorhombic (0.00≤x<0.10 and x=1.00) or tetragonal system (0.10≤x<1.00).The crystal parameter ratio c/a shows a maximum at x=0.5 caused by Jahn-Teller distortion in octahedral site of the low-spin Ni3+ ions.The magnetic susceptibilities of the mixed oxides follow the Curie-Weiss rule at temperatures 77~250K.An antiferomagne exchange interaction was observed in all the samples.The change of electrical properties in the system of x>0.5 is attributed to the change of electronic configuration of Ni3+ from t2g6dZ21 to t2g6dx2-y21.
1994, 11(3): 45-48
Abstract:
Etherification of 3,19-dihydroxy-1-thia-5,8,11,14,17-pentaoxa-cycloicosane with a series of alkyl,alkenyl,and arylalkyl halides takes place smoothly in diglyme and in the presence of NaHas a base.Dihexyloxy,didodecyloxy,dihexyldecyloxy,dibenzyloxy,and diallyloxy thia -20-crown -6 were prepared via the etherification,and four monolariat thiacrovvn ethers were also obtained as by prodticts.A polyester with thiacrown ether moieties incorporated in main chain can be obtained easily by polycondensation of dihydroxy thiacrown ether with sticcinyl chloride in the presence of pyridine.
Etherification of 3,19-dihydroxy-1-thia-5,8,11,14,17-pentaoxa-cycloicosane with a series of alkyl,alkenyl,and arylalkyl halides takes place smoothly in diglyme and in the presence of NaHas a base.Dihexyloxy,didodecyloxy,dihexyldecyloxy,dibenzyloxy,and diallyloxy thia -20-crown -6 were prepared via the etherification,and four monolariat thiacrovvn ethers were also obtained as by prodticts.A polyester with thiacrown ether moieties incorporated in main chain can be obtained easily by polycondensation of dihydroxy thiacrown ether with sticcinyl chloride in the presence of pyridine.
1994, 11(3): 49-53
Abstract:
The synergistic extraction of rare earth elemcnts (Ⅲ) including La,Nd,Gd,Er,Dy,Yb and Y from aqueous mineral acid (H2SO4,HCl,HNO3,) with benzene solution of bis (2,4,4-trimethylpentyl) phosphinic acid (BTMPPA,HL) and 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5(HPMBP,hA) has been studied.The compositions of the extracted complexes and the mechanism of the synergistic extraction have been determined by the methods of slope and constant molarity.The equilibium constants have been calculated.
The synergistic extraction of rare earth elemcnts (Ⅲ) including La,Nd,Gd,Er,Dy,Yb and Y from aqueous mineral acid (H2SO4,HCl,HNO3,) with benzene solution of bis (2,4,4-trimethylpentyl) phosphinic acid (BTMPPA,HL) and 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5(HPMBP,hA) has been studied.The compositions of the extracted complexes and the mechanism of the synergistic extraction have been determined by the methods of slope and constant molarity.The equilibium constants have been calculated.
1994, 11(3): 54-57
Abstract:
FTIR,TG and TBA tochniques have been used to study the curing process of abrasion-resistant organosilicone coatings used for transparent plastics.The dehydration rate of the associated hydroxy groups in the organosilicone colloid was very fast at the initial time,while the dehydration degree was higher at higher curing temperatures,especially at 105~130℃.The absorbtion peak appeared at 1728.9cm-1 is attributed to the acetyl group due to the isomerization of oxirane in KH-560.
FTIR,TG and TBA tochniques have been used to study the curing process of abrasion-resistant organosilicone coatings used for transparent plastics.The dehydration rate of the associated hydroxy groups in the organosilicone colloid was very fast at the initial time,while the dehydration degree was higher at higher curing temperatures,especially at 105~130℃.The absorbtion peak appeared at 1728.9cm-1 is attributed to the acetyl group due to the isomerization of oxirane in KH-560.
1994, 11(3): 62-65
Abstract:
Structure of elastomeric polyurethane (PU)/polycarbonate (PC) blends obtained ria dissolvation in DMF has been studied by DSC,wide angle X-ray diffraction (WAXD),and small angle X-ray scattering (SAXS).In the blends,the glass transition temperature of PU increases with increasing the content of PC,the melting point of PC crystals is lower than that of pure PC.All the samples have a peak at the close positions on their SAXS curves.The results show that PU and PC are partially miscible and the long period of PU's micro-phases is close to that of the solvent-induced crystal of PC.
Structure of elastomeric polyurethane (PU)/polycarbonate (PC) blends obtained ria dissolvation in DMF has been studied by DSC,wide angle X-ray diffraction (WAXD),and small angle X-ray scattering (SAXS).In the blends,the glass transition temperature of PU increases with increasing the content of PC,the melting point of PC crystals is lower than that of pure PC.All the samples have a peak at the close positions on their SAXS curves.The results show that PU and PC are partially miscible and the long period of PU's micro-phases is close to that of the solvent-induced crystal of PC.
1994, 11(3): 66-71
Abstract:
Polyvinyl chloride (PVC) has been blended with solid stated chlorinated polyethylene (CPE).The dependence of the compatibility of the blends on the mixing methods,chlorine content in CPE has been investigated.The dynamic mechanical analysis results showed that the PVC/CPE blends are partially compatible.The compatibility of the blends increaseswith increasing chlorine content in CPE and is affected by methods of blending.The CPEhaving continual
CH2CHCl
segments showed a better compatibility with PVC.The morphology of the blends showed that CPEs are distributed on the surface of the PVC particle in aform of continual network.
Polyvinyl chloride (PVC) has been blended with solid stated chlorinated polyethylene (CPE).The dependence of the compatibility of the blends on the mixing methods,chlorine content in CPE has been investigated.The dynamic mechanical analysis results showed that the PVC/CPE blends are partially compatible.The compatibility of the blends increaseswith increasing chlorine content in CPE and is affected by methods of blending.The CPEhaving continual
CH2CHCl segments showed a better compatibility with PVC.The morphology of the blends showed that CPEs are distributed on the surface of the PVC particle in aform of continual network.
1994, 11(3): 72-74
Abstract:
Polyoxyalkylene macromers containing allyl end group were synthesized from polyoxyethylene-polyoxypropylene block copolymers and allyl chloride using tetrabutylammonium bromide as catalyst.The influences of catalysts amounts,solvents and reaction temperature and reaction time on the yield have been studied.The optimum conditions are reported.Compared with the Williamson's method,this method gave a higher yield of allyl termination in polyoxyalkylene macromer preparation.
Polyoxyalkylene macromers containing allyl end group were synthesized from polyoxyethylene-polyoxypropylene block copolymers and allyl chloride using tetrabutylammonium bromide as catalyst.The influences of catalysts amounts,solvents and reaction temperature and reaction time on the yield have been studied.The optimum conditions are reported.Compared with the Williamson's method,this method gave a higher yield of allyl termination in polyoxyalkylene macromer preparation.
1994, 11(3): 75-77
Abstract:
The title compound was synthesized in 80% yield by the reaction of 4-chlorophenyl cyclopropyl ketone oxime and a by-product from a sumicidin and cypermethrinfactory,3-phenoxybenzyltrielhylammonium chloride in the alkaline condition.
The title compound was synthesized in 80% yield by the reaction of 4-chlorophenyl cyclopropyl ketone oxime and a by-product from a sumicidin and cypermethrinfactory,3-phenoxybenzyltrielhylammonium chloride in the alkaline condition.
1994, 11(3): 78-80
Abstract:
The urea decomposition caused by urease in the presence of some inhibitors:nicked nitrate,phosphates,and EDTA has been studied by tising a NH3-gas selective elec-trode.The mechamism of the decomposition reaction has been discussed.
The urea decomposition caused by urease in the presence of some inhibitors:nicked nitrate,phosphates,and EDTA has been studied by tising a NH3-gas selective elec-trode.The mechamism of the decomposition reaction has been discussed.
1994, 11(3): 81-83
Abstract:
The tissues of strawberry,radish and tomato have been chosen as biocatalvtic ma-terials,coupled with ammonia gas sensing electode to prepare three kinds of tissue sensorwhich can be used to determine L-glutamine.Their operational conditions and performancewere studied systematically.The tissue sensors are easy to fabricate,low cost and have alifetime of 4~6 days.
The tissues of strawberry,radish and tomato have been chosen as biocatalvtic ma-terials,coupled with ammonia gas sensing electode to prepare three kinds of tissue sensorwhich can be used to determine L-glutamine.Their operational conditions and performancewere studied systematically.The tissue sensors are easy to fabricate,low cost and have alifetime of 4~6 days.
1994, 11(3): 84-85
Abstract:
The ion exchange in NaY zeolite with La(NO3)3 solution under microwave radiation is reported.The results show that the microwave radiation enhanced the degree of exchange of La3+ and much reduced the times of process.
The ion exchange in NaY zeolite with La(NO3)3 solution under microwave radiation is reported.The results show that the microwave radiation enhanced the degree of exchange of La3+ and much reduced the times of process.
1994, 11(3): 86-88
Abstract:
A sensitive twice dual-wavelength spectrophoto-metric method has been developed for the simultaneous determination of trace Hg and Pb,based on the formation of colour complexes of the two metals with meso-tetra-(p-trimethylammonium phenyl) porphyrin in 0.02mol/L NaOH medium.The molar absorptivities are 4.59×105 and 4.32×105 L·mol-1·cm-1 for Pb and Hg respectively.The method gave satisfactory restilts in simultaneous determination of Pb and Hg in the tap water.
A sensitive twice dual-wavelength spectrophoto-metric method has been developed for the simultaneous determination of trace Hg and Pb,based on the formation of colour complexes of the two metals with meso-tetra-(p-trimethylammonium phenyl) porphyrin in 0.02mol/L NaOH medium.The molar absorptivities are 4.59×105 and 4.32×105 L·mol-1·cm-1 for Pb and Hg respectively.The method gave satisfactory restilts in simultaneous determination of Pb and Hg in the tap water.
1994, 11(3): 89-91
Abstract:
2α,3α-Diacetoxy-22R,23R-epoxy-6-stigmasterone (3) and 2α,3α-epoxy-22R,23R-epoxy 6-stigmasterone (4) were synthesized in high yield and selectivity from stigmasterol via peroxybenzoic acid oxidation of the double bonds which were introduced by modification of A/B rings in stigmasterol.The both epoxidized compounds easily gave 2α,3α,22R,23R-tetraacetoxy-6-stigmasterone by treatment with HBr-HOAc and H2O-HOAc.
2α,3α-Diacetoxy-22R,23R-epoxy-6-stigmasterone (3) and 2α,3α-epoxy-22R,23R-epoxy 6-stigmasterone (4) were synthesized in high yield and selectivity from stigmasterol via peroxybenzoic acid oxidation of the double bonds which were introduced by modification of A/B rings in stigmasterol.The both epoxidized compounds easily gave 2α,3α,22R,23R-tetraacetoxy-6-stigmasterone by treatment with HBr-HOAc and H2O-HOAc.
1994, 11(3): 92-95
Abstract:
The acyl thiourea derivatives 2a~o were synthesized by addition reaction of acyl isothiocvanates with amines.The structures of the compounds were confirmed by elemental analyses,IR and 1H NMR measurements.The preliminary physiological activity tests showed that compotinds 2j and 2i have notable positive effect on the germination of maize seeds and the respiratory rate as well as on their chlorophyll contents in the seedling leaves.
The acyl thiourea derivatives 2a~o were synthesized by addition reaction of acyl isothiocvanates with amines.The structures of the compounds were confirmed by elemental analyses,IR and 1H NMR measurements.The preliminary physiological activity tests showed that compotinds 2j and 2i have notable positive effect on the germination of maize seeds and the respiratory rate as well as on their chlorophyll contents in the seedling leaves.
1994, 11(3): 96-100
Abstract:
Fourteen dichloromaleimide organotin compounds were synthesized and the NMR (1H,13C,119Sn),IR,MS and elemental analysis have been recorded and studied.The results of bioassay tests showed that their bioactivities are mainly determined by the alkyl groups on the tin atom.
Fourteen dichloromaleimide organotin compounds were synthesized and the NMR (1H,13C,119Sn),IR,MS and elemental analysis have been recorded and studied.The results of bioassay tests showed that their bioactivities are mainly determined by the alkyl groups on the tin atom.
1994, 11(3): 101-103
Abstract:
Two amphoteric stirfactants were prepared from lauric acid.stearic acid and N-(β-hydroxyethyl) ethylene diamine via cyclization,reduction and qtiaternarization.Their surface tension,CMC and foaming ability were measured.
Two amphoteric stirfactants were prepared from lauric acid.stearic acid and N-(β-hydroxyethyl) ethylene diamine via cyclization,reduction and qtiaternarization.Their surface tension,CMC and foaming ability were measured.
1994, 11(3): 104-106
Abstract:
A new rare earth catalyst system was found.It is composed of (β-CH3-allyl)2LnCl5Mg·2TMED(Ln)-R3Al(Al)(Ln=Nd,Ce and La,TMED:N,N,N',N'-tetramethyl-ethylendiamine;R=Me-,Et-,i-Bu- and Oct-) for stereocontrol of isoprene polymerization.The catalyst was capable of carying stereoregularity of polyisoprene (PIP) in the wider range by changing the polymerization temperature,polymerization time,Al/Ln molar ratio,and solvent and giving lower molectilar weight polymers.The contents of cis-1,4-,trans-1,4,and 3,4-unit in PIPs ranged from 19% to 79%,17% to 78% and 0 to 3.5%,respectively.
A new rare earth catalyst system was found.It is composed of (β-CH3-allyl)2LnCl5Mg·2TMED(Ln)-R3Al(Al)(Ln=Nd,Ce and La,TMED:N,N,N',N'-tetramethyl-ethylendiamine;R=Me-,Et-,i-Bu- and Oct-) for stereocontrol of isoprene polymerization.The catalyst was capable of carying stereoregularity of polyisoprene (PIP) in the wider range by changing the polymerization temperature,polymerization time,Al/Ln molar ratio,and solvent and giving lower molectilar weight polymers.The contents of cis-1,4-,trans-1,4,and 3,4-unit in PIPs ranged from 19% to 79%,17% to 78% and 0 to 3.5%,respectively.
1994, 11(3): 107-111
Abstract:
Pyrolysis gas chromatography has been used to investigate the dealcoholization and crosslinking process of PMR type polyimide precursors,The relative amounts of the released alcohol and cyclopentadiene were selected to indicate the formation of amide or imide and the remained norbonene endcaps,respectively.The results showed that the dealcoholization is a temperattire dependent process,and it began at above 50℃ and completed at 180~220℃,Whereas,the crosslinking of the end-capped norbonene is dependent both on the temperature and time;it started at above 150℃ and completed at 280℃ for 10~18 hours.
Pyrolysis gas chromatography has been used to investigate the dealcoholization and crosslinking process of PMR type polyimide precursors,The relative amounts of the released alcohol and cyclopentadiene were selected to indicate the formation of amide or imide and the remained norbonene endcaps,respectively.The results showed that the dealcoholization is a temperattire dependent process,and it began at above 50℃ and completed at 180~220℃,Whereas,the crosslinking of the end-capped norbonene is dependent both on the temperature and time;it started at above 150℃ and completed at 280℃ for 10~18 hours.
1994, 11(3): 112-114
Abstract:
The C60 and C70 have been separated with aniline treated active carbon using column chromatography technique,The method is simple and low-cost with purity of 99.9% and 99.0% for C60 and C70,respectively.
The C60 and C70 have been separated with aniline treated active carbon using column chromatography technique,The method is simple and low-cost with purity of 99.9% and 99.0% for C60 and C70,respectively.
1994, 11(3): 115-117
Abstract:
The effects of α-methyl styrene on the rheological and mechanical properties of HIPS/SBS blends have been examined,It is found that addition of α-methyl styrene in amount of 2.5 weight percent increased the melt index of the blend by 3 times as compared with samples without additive,and their mechanical property changed only slightly.
The effects of α-methyl styrene on the rheological and mechanical properties of HIPS/SBS blends have been examined,It is found that addition of α-methyl styrene in amount of 2.5 weight percent increased the melt index of the blend by 3 times as compared with samples without additive,and their mechanical property changed only slightly.
