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1998 Volume 15 Issue 5
1998, 15(5): 1-5
Abstract:
A series of heteronuclear Ln(Ⅲ)-Co(Ⅱ) and Co(Ⅱ) complexes with bis-salicylaldehyde ethylenediamine(SALEN) have been synthesized. They were characterized as LnCo(SALEN)2(NO3)5 ° 2H2O(Ln=La,Nd,Sm,Gd,Yb,Y) and Co(SALEN)(NO3)2 ° 3H2O respectively. The differences between their compositions, structures and coordinations have been investigated by UV, IR, especially by 1H NMR and EPR spectra. The EPR spectra of the GdCo(SALEN)2(NO3)5 ° 2H2O complex in powder and various solvents at different temperatures and the "U" spectral feature, crystal-field strength and local symmetry around Gd3+ have been discussed.
A series of heteronuclear Ln(Ⅲ)-Co(Ⅱ) and Co(Ⅱ) complexes with bis-salicylaldehyde ethylenediamine(SALEN) have been synthesized. They were characterized as LnCo(SALEN)2(NO3)5 ° 2H2O(Ln=La,Nd,Sm,Gd,Yb,Y) and Co(SALEN)(NO3)2 ° 3H2O respectively. The differences between their compositions, structures and coordinations have been investigated by UV, IR, especially by 1H NMR and EPR spectra. The EPR spectra of the GdCo(SALEN)2(NO3)5 ° 2H2O complex in powder and various solvents at different temperatures and the "U" spectral feature, crystal-field strength and local symmetry around Gd3+ have been discussed.
1998, 15(5): 6-9
Abstract:
PEKK/PESEKK copolymers of high molecular weight have been synthesized by solution polycondensation of diphenyl ether, terephthaloyl chloride and 4,4'-diphenyoxydiphenyl sulfone in a catalyst/solvent system of AlCl3/ClCH2CH2Cl/NMP. The effects of monomer molarity and reaction time on copolymer molecular weight are studied. The copolymers have been characterized by IR, DSC and WAXD. The results indicate that the copolymers exhibit excellent heat-resistance. Raising PESEKK content in the copolymer increases the Tg of the copolymer, but decreases its Tm and crystallinity. The elongation at break of the copolymer is much higher than that of PEKK, but the tensile modulus and tensile strength are lower than those of PEKK.
PEKK/PESEKK copolymers of high molecular weight have been synthesized by solution polycondensation of diphenyl ether, terephthaloyl chloride and 4,4'-diphenyoxydiphenyl sulfone in a catalyst/solvent system of AlCl3/ClCH2CH2Cl/NMP. The effects of monomer molarity and reaction time on copolymer molecular weight are studied. The copolymers have been characterized by IR, DSC and WAXD. The results indicate that the copolymers exhibit excellent heat-resistance. Raising PESEKK content in the copolymer increases the Tg of the copolymer, but decreases its Tm and crystallinity. The elongation at break of the copolymer is much higher than that of PEKK, but the tensile modulus and tensile strength are lower than those of PEKK.
1998, 15(5): 10-13
Abstract:
N,N-Bis(2-hydroxyethyl)amino-1,3-benzenediol(1a) and its analogs 1b~1g have been synthesized. By condensation of squaric acid with 1a~1g, a class of novel multiarm-squaraines, namely 1,3-bis[4-N,N-bis(2-hydroxyethyl)amino-2,6-dihydroxyl phenyl] squaraine(2a) and its analogs(2b~2g) were obtained. The compounds were designed to improve the donor acceptor donor charge transfer(D-A-D CT) of squaraines. The spectra properties of the compounds have been discussed.
N,N-Bis(2-hydroxyethyl)amino-1,3-benzenediol(1a) and its analogs 1b~1g have been synthesized. By condensation of squaric acid with 1a~1g, a class of novel multiarm-squaraines, namely 1,3-bis[4-N,N-bis(2-hydroxyethyl)amino-2,6-dihydroxyl phenyl] squaraine(2a) and its analogs(2b~2g) were obtained. The compounds were designed to improve the donor acceptor donor charge transfer(D-A-D CT) of squaraines. The spectra properties of the compounds have been discussed.
1998, 15(5): 14-17
Abstract:
Four spinel-type mixed oxide nanocrystalline powders MFe2O4(M=Cu2+, Zn2+, Cd2+ and Mg2+) were prepared by chemical coprecipitation method. The products were characterized by means of powder XRD, TEM and specific surface area measurements. The results reveal that the samples are nanocrystalline powders with high specific surface areas. Their gas sensitivities to reductive gases depend on their specific surface area: the larger the specific surface area, the higher the sensitivity.
Four spinel-type mixed oxide nanocrystalline powders MFe2O4(M=Cu2+, Zn2+, Cd2+ and Mg2+) were prepared by chemical coprecipitation method. The products were characterized by means of powder XRD, TEM and specific surface area measurements. The results reveal that the samples are nanocrystalline powders with high specific surface areas. Their gas sensitivities to reductive gases depend on their specific surface area: the larger the specific surface area, the higher the sensitivity.
1998, 15(5): 18-20
Abstract:
A series of the title 2,4,6-trioxo-1,3,5,2-triazaphosphorine derivatives have been synthesized by reaction of N,N-bis(2-chloroethyl)aminophosphoryldiisocyanate with ami nes. The structures of the products were confirmed by 1H NMR, IR MS, 31P NMR and elemental analysis. The preliminary bioassay indicated that some of them had antitumor activity.
A series of the title 2,4,6-trioxo-1,3,5,2-triazaphosphorine derivatives have been synthesized by reaction of N,N-bis(2-chloroethyl)aminophosphoryldiisocyanate with ami nes. The structures of the products were confirmed by 1H NMR, IR MS, 31P NMR and elemental analysis. The preliminary bioassay indicated that some of them had antitumor activity.
1998, 15(5): 21-23
Abstract:
The lanthanide complexes LnCl3° 3PA(Ln=Pr,Nd,Eu,Dy; PA=propionamide) were synthesized. The IR results showed that PA is coordinated with Nd via its oxygen atom. The binary catalyst systems consisted of NdCl3 ° 3PA with i-Bu3Al, i-Bu2AlH, or Et3Al were all found to be very active for butadiene polymerization when the cis-1,4-content of polybutadiene is 98% or more.
The lanthanide complexes LnCl3° 3PA(Ln=Pr,Nd,Eu,Dy; PA=propionamide) were synthesized. The IR results showed that PA is coordinated with Nd via its oxygen atom. The binary catalyst systems consisted of NdCl3 ° 3PA with i-Bu3Al, i-Bu2AlH, or Et3Al were all found to be very active for butadiene polymerization when the cis-1,4-content of polybutadiene is 98% or more.
1998, 15(5): 24-27
Abstract:
Three feeding processes:single addition of all reagents together, drip feeding of monomer emulsion and dripping of initiator in preparation of the title composite copolymer emulsion have been compared. The second process appeared to be the best one. The emulsion thus obtained has smaller particle size and better stability.
Three feeding processes:single addition of all reagents together, drip feeding of monomer emulsion and dripping of initiator in preparation of the title composite copolymer emulsion have been compared. The second process appeared to be the best one. The emulsion thus obtained has smaller particle size and better stability.
1998, 15(5): 28-30
Abstract:
Three triphenyldiamine derivatives(TPDs) were synthesized by Ullmann reaction of N,N'-diphenyl benzidine with p-CH3, p-OCH3, m-CH3 iodobenzenes, respectively, using 18C6 as phase transfer catalyst and o dichlorobenzene as solvent. Their structures have been verified by IR and NMR maesurements. As a charge transfer agent, addition of TPD improves the luminescent property of the electroluminescent devices.
Three triphenyldiamine derivatives(TPDs) were synthesized by Ullmann reaction of N,N'-diphenyl benzidine with p-CH3, p-OCH3, m-CH3 iodobenzenes, respectively, using 18C6 as phase transfer catalyst and o dichlorobenzene as solvent. Their structures have been verified by IR and NMR maesurements. As a charge transfer agent, addition of TPD improves the luminescent property of the electroluminescent devices.
1998, 15(5): 31-34
Abstract:
The crystallization behavior of silane-crosslinked LDPE and peroxide-crosslinked LDPE have been compared by using DSC and WAXD techniques. It is found that the crystallinity and melt point of the peroxide-crosslinked LDPE are lower than those of the silane crosslinked LDPE when their crosslinking densities are of the same value. DSC measurements show that after crossinking the Avrami exponents (n) have no significant change, but the rate constants of crystallization decrease and the half crystallization times increase, whereas the variation range for the peroxide crosslinked LDPE is greater than that for the silane-crosslinked LDPE.
The crystallization behavior of silane-crosslinked LDPE and peroxide-crosslinked LDPE have been compared by using DSC and WAXD techniques. It is found that the crystallinity and melt point of the peroxide-crosslinked LDPE are lower than those of the silane crosslinked LDPE when their crosslinking densities are of the same value. DSC measurements show that after crossinking the Avrami exponents (n) have no significant change, but the rate constants of crystallization decrease and the half crystallization times increase, whereas the variation range for the peroxide crosslinked LDPE is greater than that for the silane-crosslinked LDPE.
1998, 15(5): 35-38
Abstract:
The nitrogen atom in a nylon-6 macromolecule could be the grafting site as determined by spectrometry and the XRD results show that the crystallinity of the grafted membrane decreases with the increase of the grafting yield. The effects of the grafting yield on the electric resistance, ion exchange capacity and tensile stress of the membrane also have been investigated.
The nitrogen atom in a nylon-6 macromolecule could be the grafting site as determined by spectrometry and the XRD results show that the crystallinity of the grafted membrane decreases with the increase of the grafting yield. The effects of the grafting yield on the electric resistance, ion exchange capacity and tensile stress of the membrane also have been investigated.
1998, 15(5): 39-42
Abstract:
4-Chlorophenyl acetaldelyde reacting with T-triazolylpinacolone in the presence of KF/Al2O3/PEG4000 will produce 85% vinyltriazolyl ketone(Ⅱ) with E/Z =0.65; Ⅱ is then isomerized by light to a yield of 92% E-Ⅱ with E/Z ≥99/1. It is then reduced in the presence of certain charge transfer catalyst V by KBH4 to 92% Uniconazole-P with ee of 30%.
4-Chlorophenyl acetaldelyde reacting with T-triazolylpinacolone in the presence of KF/Al2O3/PEG4000 will produce 85% vinyltriazolyl ketone(Ⅱ) with E/Z =0.65; Ⅱ is then isomerized by light to a yield of 92% E-Ⅱ with E/Z ≥99/1. It is then reduced in the presence of certain charge transfer catalyst V by KBH4 to 92% Uniconazole-P with ee of 30%.
1998, 15(5): 43-46
Abstract:
Crowned Schiff's base cobalt(Ⅱ) complex 1c and its analogues 1a and 1b were synthesized and their catalytic activities in cumene oxidation to cumyl hydroperoxide have been compared. The results showing that complex 1c being superior to its analogues in catalytic activity are explained in terms of their oxygen adduction constants.
Crowned Schiff's base cobalt(Ⅱ) complex 1c and its analogues 1a and 1b were synthesized and their catalytic activities in cumene oxidation to cumyl hydroperoxide have been compared. The results showing that complex 1c being superior to its analogues in catalytic activity are explained in terms of their oxygen adduction constants.
1998, 15(5): 47-49
Abstract:
4,4'-bis(U-naphthoxy)diphenylsulfone(BNODPS) was synthesized by reaction of U-naphthol with bis(4-chlorophenyl) sulfone in DMSO in the presence of KOH. Five polyaryl ether sulfone ether ketone ketones containing naphthalene links were prepared by low temperature solution polycondensation of BNODPS with terephthaloyl chloride(TPC), isophthaloyl chloride(IPC) and 2,5-dichloroterephthaloyl chloride(DCC), respectively in 1,2-dichlorothane and in the presence of AlCl3 and N-methylpyrrolidone. The polymers as characterized by IR, XRD, DSC and TG techniques are non-crystalline and have high glass transition temperature, good thermostability and solubitity.
4,4'-bis(U-naphthoxy)diphenylsulfone(BNODPS) was synthesized by reaction of U-naphthol with bis(4-chlorophenyl) sulfone in DMSO in the presence of KOH. Five polyaryl ether sulfone ether ketone ketones containing naphthalene links were prepared by low temperature solution polycondensation of BNODPS with terephthaloyl chloride(TPC), isophthaloyl chloride(IPC) and 2,5-dichloroterephthaloyl chloride(DCC), respectively in 1,2-dichlorothane and in the presence of AlCl3 and N-methylpyrrolidone. The polymers as characterized by IR, XRD, DSC and TG techniques are non-crystalline and have high glass transition temperature, good thermostability and solubitity.
1998, 15(5): 50-52
Abstract:
A polymer Schiff's base, phenylenediimido cellulose with fluorescence property was synthesized from dialdehyde cellulose with o-phenylenediamine. The optimal concentration ratio and the total concentration of the reactants were 2:1 and 6 × 10-4 g/mL, respectively. In an aqueous solution of pH 7.6 at 470 nm excitation wavelength the emission intensity of the cellulose Schiff's base reached a maximum at emission wavelength 550 nm and it then decreased with increase in the pH value of the solution.
A polymer Schiff's base, phenylenediimido cellulose with fluorescence property was synthesized from dialdehyde cellulose with o-phenylenediamine. The optimal concentration ratio and the total concentration of the reactants were 2:1 and 6 × 10-4 g/mL, respectively. In an aqueous solution of pH 7.6 at 470 nm excitation wavelength the emission intensity of the cellulose Schiff's base reached a maximum at emission wavelength 550 nm and it then decreased with increase in the pH value of the solution.
1998, 15(5): 53-55
Abstract:
The preparation of concentrated St-MAA emulsion by one-step method is investigated. The stability of the emulsion is affected by the kinds and concentration of the emulsifiers, volume fraction and polarity of the monomer. The polymerization of concentrated St MAA emulsion was carried out using azo-bis-isobutyronitrile as initiator. Results indicate that the average size and dispersity of the latex particles depend on the concentration of the surfacant and monomer fraction.
The preparation of concentrated St-MAA emulsion by one-step method is investigated. The stability of the emulsion is affected by the kinds and concentration of the emulsifiers, volume fraction and polarity of the monomer. The polymerization of concentrated St MAA emulsion was carried out using azo-bis-isobutyronitrile as initiator. Results indicate that the average size and dispersity of the latex particles depend on the concentration of the surfacant and monomer fraction.
1998, 15(5): 56-58
Abstract:
The interaction among copper ion, tyrosine and kaolinite has been investigated. The effect of tyrosine on the ion exchange percentage of copper ions adsorbed showen by the kaolinite-pH curve, E(%)-pH curve, is found to be characterized by the left-right vacillation. It is suggested that a type Ⅱ ternary surface complex is formed and its stability constant is calculated to be 1 × 101.13.
The interaction among copper ion, tyrosine and kaolinite has been investigated. The effect of tyrosine on the ion exchange percentage of copper ions adsorbed showen by the kaolinite-pH curve, E(%)-pH curve, is found to be characterized by the left-right vacillation. It is suggested that a type Ⅱ ternary surface complex is formed and its stability constant is calculated to be 1 × 101.13.
1998, 15(5): 59-61
Abstract:
The molecular structure of a water-soluble polyester prepared by copolycondensation of dimethyl terephthalate, isophthalic acid, dimethyl isophathalate-5-sulfonic sodium with ethylene glycol, etc. and its thermal, crystal and rheological properties, as well as polyelectrolyte effect have been investigated by IR, 1H NMR and rheometric techniques. The water-soluble polyester is found to be amorphous with glass temperature being 43.0 ℃ and softing point 129.7 ℃. Its melt has a shear thinning feature and shows a polyelectrolyte effect in solvents with high dielectric constant.
The molecular structure of a water-soluble polyester prepared by copolycondensation of dimethyl terephthalate, isophthalic acid, dimethyl isophathalate-5-sulfonic sodium with ethylene glycol, etc. and its thermal, crystal and rheological properties, as well as polyelectrolyte effect have been investigated by IR, 1H NMR and rheometric techniques. The water-soluble polyester is found to be amorphous with glass temperature being 43.0 ℃ and softing point 129.7 ℃. Its melt has a shear thinning feature and shows a polyelectrolyte effect in solvents with high dielectric constant.
1998, 15(5): 62-64
Abstract:
Microsize polystyrene beads with narrow size distribution were prepared in one step by dispersion polymerization. The process involes the polymerization of the monomer dissolved in a mixture consisted of methyl cellosolve, ethanol, diisooctylsulfosuccinic sodium, azo isobutyronitrile and polyvinylpyrrolidone as a steric stabilizer. The factors influencing the particle size of polystyrene beads have been investigated.
Microsize polystyrene beads with narrow size distribution were prepared in one step by dispersion polymerization. The process involes the polymerization of the monomer dissolved in a mixture consisted of methyl cellosolve, ethanol, diisooctylsulfosuccinic sodium, azo isobutyronitrile and polyvinylpyrrolidone as a steric stabilizer. The factors influencing the particle size of polystyrene beads have been investigated.
1998, 15(5): 65-67
Abstract:
A series of nanocrystallite perovskite-type LaCoO3 were prepared by coprecipitation method using oxalic acid as precipitant. The results of DTA, TGA, XRD and TEM observations showed that the drying condition causes a significant effect on the structure and formation mechanism of the products.
A series of nanocrystallite perovskite-type LaCoO3 were prepared by coprecipitation method using oxalic acid as precipitant. The results of DTA, TGA, XRD and TEM observations showed that the drying condition causes a significant effect on the structure and formation mechanism of the products.
1998, 15(5): 68-70
Abstract:
The title compound, an antifeedant, has been successfully synthesized from 1,3,5-trihydroxybenzene and anisaldehyde in six steps:Hoesch Houben reaction, methylation, protection, condensation, Algar-Flynn-Oyamade reaction and deprotection.
The title compound, an antifeedant, has been successfully synthesized from 1,3,5-trihydroxybenzene and anisaldehyde in six steps:Hoesch Houben reaction, methylation, protection, condensation, Algar-Flynn-Oyamade reaction and deprotection.
1998, 15(5): 71-73
Abstract:
A violent streamer discharge produced by ultra-strong narrow pulse electric field in the whole reactor makes N2 and H2 ionize and dissociate to transform a large number of free atoms, ions and radicals forming a non-equilibrium plasma at normal pressure. The concentration of NH3 gas thus synthesized could reach 4884 μL/L.
A violent streamer discharge produced by ultra-strong narrow pulse electric field in the whole reactor makes N2 and H2 ionize and dissociate to transform a large number of free atoms, ions and radicals forming a non-equilibrium plasma at normal pressure. The concentration of NH3 gas thus synthesized could reach 4884 μL/L.
1998, 15(5): 74-76
Abstract:
The structure, morphology, thermal stability and mechnical properties of styrene butadiene rubber/poly(propylene carbonate)(SBR/PPC) blends are studied. The blend system exhibits a phase separation morphology, and the PPC is attached to the elastomer network. The blend shows excellent tensile property and better heat stability in comparison with the single SBR elastomer.
The structure, morphology, thermal stability and mechnical properties of styrene butadiene rubber/poly(propylene carbonate)(SBR/PPC) blends are studied. The blend system exhibits a phase separation morphology, and the PPC is attached to the elastomer network. The blend shows excellent tensile property and better heat stability in comparison with the single SBR elastomer.
1998, 15(5): 77-79
Abstract:
The green emission peroxalate chemiluminescence system was prepared with bis(2-butoxycarbonyl-3,4,6-trichlorophenyl)oxalate and 9,10-bis(phenylethynyl)anthracene. Some factors affecting the light capacity and light intensity of the system have been studied. The optimum formulation of the system is presented. The chemiluminescene system decribed will give efficient illumination for ca. 6 hours.
The green emission peroxalate chemiluminescence system was prepared with bis(2-butoxycarbonyl-3,4,6-trichlorophenyl)oxalate and 9,10-bis(phenylethynyl)anthracene. Some factors affecting the light capacity and light intensity of the system have been studied. The optimum formulation of the system is presented. The chemiluminescene system decribed will give efficient illumination for ca. 6 hours.
1998, 15(5): 80-82
Abstract:
The polymerizable non-ionic oil-soluble emulsifier, acryloyl sorbitan monostearate(ASMS) is synthesized from sorbitan monostearate(SMS) and acryloyl chloride. ASMS shows a greater solubility in some organic solvents than SMS. The inverse latex is prepared from acryl amide and emulsifier in the presence of an initiator. The ASMS stabilized PAM inverse latex has a greater stability than those SMS stabilized latex and its final particle size is controlled by the concentration of ASMS in it. The rheological curves for both the stabilized latexes are presented.
The polymerizable non-ionic oil-soluble emulsifier, acryloyl sorbitan monostearate(ASMS) is synthesized from sorbitan monostearate(SMS) and acryloyl chloride. ASMS shows a greater solubility in some organic solvents than SMS. The inverse latex is prepared from acryl amide and emulsifier in the presence of an initiator. The ASMS stabilized PAM inverse latex has a greater stability than those SMS stabilized latex and its final particle size is controlled by the concentration of ASMS in it. The rheological curves for both the stabilized latexes are presented.
1998, 15(5): 83-85
Abstract:
Various factors that influence Au 3+ extraction are studied. These factors include composition of the oil membranes and reactant in the internal phase, separating conditions and de-emulsification method. Experimental results show that liquid surfactant membranes are suitable for extraction of gold from its solution of very low concentration (~2 × 10-6g/L). The extraction efficiency can reach 99% and even more.
Various factors that influence Au 3+ extraction are studied. These factors include composition of the oil membranes and reactant in the internal phase, separating conditions and de-emulsification method. Experimental results show that liquid surfactant membranes are suitable for extraction of gold from its solution of very low concentration (~2 × 10-6g/L). The extraction efficiency can reach 99% and even more.
1998, 15(5): 86-88
Abstract:
Perylene monoanhydride monoimide was prepared by reaction of perylene anhydride and benzylamine in water pyridine mixture of pH 6.4~6.7. It was then condensed with ethanolamine and acrylchloride to give an unsymetrical perylene monomer N-benzyl N'-(2-acrylate ethyl)-3,4,9,10-tetracarboxylic diimide. Polymerization of the diimide with acrylamide gave a new type polymer containing perylene structure. The new polymer has different visible and fluorescence properties from the perylene monomer and improved solubility and film formation properties.
Perylene monoanhydride monoimide was prepared by reaction of perylene anhydride and benzylamine in water pyridine mixture of pH 6.4~6.7. It was then condensed with ethanolamine and acrylchloride to give an unsymetrical perylene monomer N-benzyl N'-(2-acrylate ethyl)-3,4,9,10-tetracarboxylic diimide. Polymerization of the diimide with acrylamide gave a new type polymer containing perylene structure. The new polymer has different visible and fluorescence properties from the perylene monomer and improved solubility and film formation properties.
1998, 15(5): 89-91
Abstract:
A series of the title compounds were synthesized by addition reaction of dialkyl-hydroxyphosphonates with phenyl isocyanate in the presence of sodium methoxide. All compounds were identified by 1H NMR, 31 P NMR, IR and elemental analysis. The preliminary biological tests indicated that some compounds had plant growth regulating activities.
A series of the title compounds were synthesized by addition reaction of dialkyl-hydroxyphosphonates with phenyl isocyanate in the presence of sodium methoxide. All compounds were identified by 1H NMR, 31 P NMR, IR and elemental analysis. The preliminary biological tests indicated that some compounds had plant growth regulating activities.
1998, 15(5): 92-94
Abstract:
The contents of Cd and Pb in soybean seedling and the ecophysiological effect of La on the injury of Cd and Pb to the plant have been investigated. The results showed that the culture containing solutions of 500 mg/L of CdCl3 or 1000 mg/L of Pb(Ac)2 inhibited the growth of the soybean seedling and increased Cd or Pb content in it, and spraying one with LaCl3 solution in concentration of 30 mg/L to the seedling could reduced their injury effect and content in the plant.
The contents of Cd and Pb in soybean seedling and the ecophysiological effect of La on the injury of Cd and Pb to the plant have been investigated. The results showed that the culture containing solutions of 500 mg/L of CdCl3 or 1000 mg/L of Pb(Ac)2 inhibited the growth of the soybean seedling and increased Cd or Pb content in it, and spraying one with LaCl3 solution in concentration of 30 mg/L to the seedling could reduced their injury effect and content in the plant.
1998, 15(5): 95-97
Abstract:
The fluorescence spectra of the mixture of phenol, resorcin and 1,3,5-trihydroxybenzene have been analyzed by multiwavelength linear regression method. In a buffered pH=6.86 solution the detection limit of phenol, resorcin and 1,3,5-trihydroxybenzene was found to be 0.48, 0.51 and 0.67 μg/L, respectively. The method has been applied to the simultaneous determination of the above phenols in the synthetical samples and pharmaceutical preparations with recoveries being in the range of 93 7%~106%.
The fluorescence spectra of the mixture of phenol, resorcin and 1,3,5-trihydroxybenzene have been analyzed by multiwavelength linear regression method. In a buffered pH=6.86 solution the detection limit of phenol, resorcin and 1,3,5-trihydroxybenzene was found to be 0.48, 0.51 and 0.67 μg/L, respectively. The method has been applied to the simultaneous determination of the above phenols in the synthetical samples and pharmaceutical preparations with recoveries being in the range of 93 7%~106%.
1998, 15(5): 98-100
Abstract:
Fibrous electrolytic manganese dioxide(EMD) was prepared from manganous chloride solution by electrolyzing at 90~95 ℃ and using graphite anode. EMD has the exchange properties with cations in aqueous chloride solutions. A lithium type ionic sieve made from EMD substrate may be used for selective adsorption of trace lithium from sea water with yield of about 90%.
Fibrous electrolytic manganese dioxide(EMD) was prepared from manganous chloride solution by electrolyzing at 90~95 ℃ and using graphite anode. EMD has the exchange properties with cations in aqueous chloride solutions. A lithium type ionic sieve made from EMD substrate may be used for selective adsorption of trace lithium from sea water with yield of about 90%.
1998, 15(5): 101-103
Abstract:
An organic inorganic hybrid material was synthesized from tetrabutoxyorthotitanate and methylethoxysilane by sol-gel method. The factors affecting the physico chemical properties and structures of the products have been investigated.
An organic inorganic hybrid material was synthesized from tetrabutoxyorthotitanate and methylethoxysilane by sol-gel method. The factors affecting the physico chemical properties and structures of the products have been investigated.
1998, 15(5): 104-105
Abstract:
Tellurium of high purity (99.999%) was prepared from technical tellurium (99%) through oxidation to tellurium dioxide, dissolution in NaOH, changing into Na2TeO4 by treatment with Na2S° 9H2O and H2O2, successively. The HCl solution of Na2TeO4 was then treated with SO2 gas to give high purity tellurium.
Tellurium of high purity (99.999%) was prepared from technical tellurium (99%) through oxidation to tellurium dioxide, dissolution in NaOH, changing into Na2TeO4 by treatment with Na2S° 9H2O and H2O2, successively. The HCl solution of Na2TeO4 was then treated with SO2 gas to give high purity tellurium.
1998, 15(5): 106-107
Abstract:
4-(4-Amino-3-methylphenylazo) benzenesulfonic acid has been synthesized. It is shown that with the increase in reaction temperature and NaOH concentration the cleavage of -CH2SO3Na becomes faster. When the coupling reaction is processed at pH=7~7.5 and the cleavage reaction is processed under the condition of reaction temperature of 90 ℃ and NaOH concentration of 100 g/L, the product yield is about 84 3%.
4-(4-Amino-3-methylphenylazo) benzenesulfonic acid has been synthesized. It is shown that with the increase in reaction temperature and NaOH concentration the cleavage of -CH2SO3Na becomes faster. When the coupling reaction is processed at pH=7~7.5 and the cleavage reaction is processed under the condition of reaction temperature of 90 ℃ and NaOH concentration of 100 g/L, the product yield is about 84 3%.
1998, 15(5): 108-110
Abstract:
A polymer dye has been synthesized by copolymerization of a dye-functionalized prepolymer based on polyurethane with methylmethacrylate. The composition of the copolymer has been analyzed by UV spectrometry. The effects of stock composition, reaction time and amount of initiator on the composition of copolymers have been studied. Results show that the dye-functionalized monomer is more reactive than methylmethacrylate in the course of copolymerization.
A polymer dye has been synthesized by copolymerization of a dye-functionalized prepolymer based on polyurethane with methylmethacrylate. The composition of the copolymer has been analyzed by UV spectrometry. The effects of stock composition, reaction time and amount of initiator on the composition of copolymers have been studied. Results show that the dye-functionalized monomer is more reactive than methylmethacrylate in the course of copolymerization.
1998, 15(5): 111-112
Abstract:
An improved method for preparation of closo dodecaborate B12 H122- with yield of 89.8% is described. The improved reaction conditions and separation procedure of the product for thermal decomposition of B3H8- to B12 H122- in diglyme are given. The method is suitable for routine preparation.
An improved method for preparation of closo dodecaborate B12 H122- with yield of 89.8% is described. The improved reaction conditions and separation procedure of the product for thermal decomposition of B3H8- to B12 H122- in diglyme are given. The method is suitable for routine preparation.
1998, 15(5): 113-114
Abstract:
Diazoresins derived from diphenylamine 4-diazonium salt(DDS) and 3-methoxydiphenylamine-4-diazonium salt(MDDS) with various organic anions were prepared and their thermal decomposition temperatures(Td) were determined. The results showed that the diazoresins from MDDS exhibited higher Td than that from DDS and the diazoresins with BHMS(3-benzoyl-4-hydroxyl-6-methoxybenzsulfonic acid), NS(2-naphthalene sulfonic acid), DB-NS(4,8-dibutyl-2-naphthalene sulfonic acid) or PSS(polystyrene sulfonic acid) as anion possess higher Td than that with DBS(dodecylbenzsulfonic acid) or SDS(dodecylsulfuric acid) as anion, but close to that with HSO4- as anion. The photoimaging behavior of the diazoresins with organic anion was examined.
Diazoresins derived from diphenylamine 4-diazonium salt(DDS) and 3-methoxydiphenylamine-4-diazonium salt(MDDS) with various organic anions were prepared and their thermal decomposition temperatures(Td) were determined. The results showed that the diazoresins from MDDS exhibited higher Td than that from DDS and the diazoresins with BHMS(3-benzoyl-4-hydroxyl-6-methoxybenzsulfonic acid), NS(2-naphthalene sulfonic acid), DB-NS(4,8-dibutyl-2-naphthalene sulfonic acid) or PSS(polystyrene sulfonic acid) as anion possess higher Td than that with DBS(dodecylbenzsulfonic acid) or SDS(dodecylsulfuric acid) as anion, but close to that with HSO4- as anion. The photoimaging behavior of the diazoresins with organic anion was examined.
1998, 15(5): 115-116
Abstract:
The properties of sodium carboxymethylcellulose(NaCMC)/hydroxyethylcellulose(HEC) compound solution such as viscosification efficiency, rheological behavior, shear stability and salt stability have been investigated by means of rotation viscosimeter. The results show that the compound solution exhibits an enhanced viscosification efficiency, improved shear stability, as well as a better tolerance towards temperature and salt.
The properties of sodium carboxymethylcellulose(NaCMC)/hydroxyethylcellulose(HEC) compound solution such as viscosification efficiency, rheological behavior, shear stability and salt stability have been investigated by means of rotation viscosimeter. The results show that the compound solution exhibits an enhanced viscosification efficiency, improved shear stability, as well as a better tolerance towards temperature and salt.
