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2004 Volume 21 Issue 5
2004, 21(5): 433-436
Abstract:
The extraction and separation processes of the main anthraquinones in Polygonum Cuspidatum, including emodin, rhein and physcion, have been carried out and improved. More pure emodin products without physcion could be obtained from a small amount and by repetitive extraction and stepwise collection. The extraction yields of emodin and physcion were more than 70%, with purity greater than 96%. The HPLC analysis method of anthraquinones was improved by using C18 column instead of C8 column, with detection wave-length of 437 nm. The method could afford to simutanniously determine the main anthraquinones in Polygonum Cuspidatum.
The extraction and separation processes of the main anthraquinones in Polygonum Cuspidatum, including emodin, rhein and physcion, have been carried out and improved. More pure emodin products without physcion could be obtained from a small amount and by repetitive extraction and stepwise collection. The extraction yields of emodin and physcion were more than 70%, with purity greater than 96%. The HPLC analysis method of anthraquinones was improved by using C18 column instead of C8 column, with detection wave-length of 437 nm. The method could afford to simutanniously determine the main anthraquinones in Polygonum Cuspidatum.
2004, 21(5): 437-441
Abstract:
The effects of calcination temperatures and Sb content in SnO2+Sb2O3 intermediate layers prepared from polymeric precursor on the performance of the Ti/SnO2+Sb2O3/PbO2 anodes have been studied. The SnO2+Sb2O3 intermediate layers were characterized by XRD,SEM and a probe method. The anode performance was assessed with the polarization curve, the cathodic voltammetric charge and the fast lifetime determinations in the 1.0 mol/L H2SO4 solution. It was found that calcination temperature and Sb content in SnO2+Sb2O3 intermediate layer obviously affected the performance of the Ti/SnO2+Sb2O3/PbO2 anode. For anode containing intermediate layer calcinated at 500℃ and with n(Sn):n(Sb)=9:1 the anode life achived 30 h in 1.0 mol/L H2SO4 solutions and with good stability.
The effects of calcination temperatures and Sb content in SnO2+Sb2O3 intermediate layers prepared from polymeric precursor on the performance of the Ti/SnO2+Sb2O3/PbO2 anodes have been studied. The SnO2+Sb2O3 intermediate layers were characterized by XRD,SEM and a probe method. The anode performance was assessed with the polarization curve, the cathodic voltammetric charge and the fast lifetime determinations in the 1.0 mol/L H2SO4 solution. It was found that calcination temperature and Sb content in SnO2+Sb2O3 intermediate layer obviously affected the performance of the Ti/SnO2+Sb2O3/PbO2 anode. For anode containing intermediate layer calcinated at 500℃ and with n(Sn):n(Sb)=9:1 the anode life achived 30 h in 1.0 mol/L H2SO4 solutions and with good stability.
2004, 21(5): 442-445
Abstract:
Four 2-(4-chlorophenyl)-3-methyl-butyl phosphorates and four 3-(2,2-dichloroviny)-2,2-dimethyl-cyclopropane carboxyl phosphorates were synthesized from the intermediate α-hydroxylaryl phosphorates with 2-(4-chlorophenyl)-3-methyl-butyl chloride and 3-(2,2-dichlorovinyl)-2,2-dimethyl-cyclopropane carbonyl chloride, respectively. All compounds synthesized were identified by 1H NMR, IR and MS. Preliminary bioassay showed that compounds 4b, 4d and 5a, have consierable acaridcidal activities.
Four 2-(4-chlorophenyl)-3-methyl-butyl phosphorates and four 3-(2,2-dichloroviny)-2,2-dimethyl-cyclopropane carboxyl phosphorates were synthesized from the intermediate α-hydroxylaryl phosphorates with 2-(4-chlorophenyl)-3-methyl-butyl chloride and 3-(2,2-dichlorovinyl)-2,2-dimethyl-cyclopropane carbonyl chloride, respectively. All compounds synthesized were identified by 1H NMR, IR and MS. Preliminary bioassay showed that compounds 4b, 4d and 5a, have consierable acaridcidal activities.
2004, 21(5): 446-449
Abstract:
Nano-particles Ni(OH)2 were prepared from PEG solution of Ni(NO3)2 by chemical precipitation method and characterized by XRD and TEM techniques. The results indicated the sample is nano-phase β-Ni(OH)2 with average size of 48 nm. The gavanostatic charge-discharge test and the cyclic voltammetry demonstrated the resultant sample has a higher electrochemical activity. Its specific capacity reaches 96.5% of the ideal capacity and stronger anti-overchargeability.
Nano-particles Ni(OH)2 were prepared from PEG solution of Ni(NO3)2 by chemical precipitation method and characterized by XRD and TEM techniques. The results indicated the sample is nano-phase β-Ni(OH)2 with average size of 48 nm. The gavanostatic charge-discharge test and the cyclic voltammetry demonstrated the resultant sample has a higher electrochemical activity. Its specific capacity reaches 96.5% of the ideal capacity and stronger anti-overchargeability.
2004, 21(5): 450-454
Abstract:
Two kinds of quaternary ammonium tetraphenylborates(QA salt-BPh4) have been synthesized and characterized by elemental analysis, nuclear magnetic resonance spectroscopy and UV spectroscopy. The polymerization of tri-methylolpropane triacrylate(TMPTA) initiated by them under UV light illumination appeared to be radical polymerization and could be inhibited by oxygen. It was found from the results of photo-DSC of TMPTA at different temperature that the photoinitiation efficiency increased with polymerization temperature and the activation energy was calculated to be 44.4 kJ/mol. Thermogravimetry proved that the product had very good thermostability.
Two kinds of quaternary ammonium tetraphenylborates(QA salt-BPh4) have been synthesized and characterized by elemental analysis, nuclear magnetic resonance spectroscopy and UV spectroscopy. The polymerization of tri-methylolpropane triacrylate(TMPTA) initiated by them under UV light illumination appeared to be radical polymerization and could be inhibited by oxygen. It was found from the results of photo-DSC of TMPTA at different temperature that the photoinitiation efficiency increased with polymerization temperature and the activation energy was calculated to be 44.4 kJ/mol. Thermogravimetry proved that the product had very good thermostability.
2004, 21(5): 455-458
Abstract:
Three kinds of iridoid compounds:geniposidic acid(GPA), aucubin(AU) and geniposide(GP) were separated in pure form from the extract of eucommia ulmiodes simultaneously by preparative liquid chromatography. The elution mode, the flow-rate and the composition of the mobile phase including the content of the additive were investigated. A gradient flow rate elution mode was proposed. The optimum condition of the separation of the mixture as follows:mobile phase ethanol-water-formic acid(volume ratio 18:82:0.09), the reverse C18 column was eluted by gradient flow rate, 30 mL/min followed with 55 mL/min. 95.61% of AU, 98.22% of GPA and 98.54% of GP were obtained respectively.
Three kinds of iridoid compounds:geniposidic acid(GPA), aucubin(AU) and geniposide(GP) were separated in pure form from the extract of eucommia ulmiodes simultaneously by preparative liquid chromatography. The elution mode, the flow-rate and the composition of the mobile phase including the content of the additive were investigated. A gradient flow rate elution mode was proposed. The optimum condition of the separation of the mixture as follows:mobile phase ethanol-water-formic acid(volume ratio 18:82:0.09), the reverse C18 column was eluted by gradient flow rate, 30 mL/min followed with 55 mL/min. 95.61% of AU, 98.22% of GPA and 98.54% of GP were obtained respectively.
2004, 21(5): 459-463
Abstract:
The interaction of bacillus subtilis proteinase(BSP) and sodium 3,4-dihydro-2-anthraquinone sulfonate(Alizarin Red S, ARS) was investigated by spectrophotometric method in acidic solution(pH=4.20). The red color of the solution indicates the formation of the new compound. The maximum absorption peak of the colored species was at 515 nm. It is shifted from 420 nm of ARS. Balance dialysis method, molar ratio method and double wavelengh method were adopted to investigate the association formation. The following results were obtained:binding number n1=13, n1=45; apparent molar absorptivity εB1=5.89×103 L/(mol·cm), εB2=4.68×103 L/(mol·cm); accumulative equilibrium constant β1=5.27×104 L/mol, β2=3.54×105 L/mol. It is found that combination of BSP with ARS conforms to Scatchard model and the first type binding number completely conform to functional atom number of BSP activity center in its space conformation. It is suggested that the combination between BSP and ARS is due to the electrostatic force(primary action force) and hydrophobic force.
The interaction of bacillus subtilis proteinase(BSP) and sodium 3,4-dihydro-2-anthraquinone sulfonate(Alizarin Red S, ARS) was investigated by spectrophotometric method in acidic solution(pH=4.20). The red color of the solution indicates the formation of the new compound. The maximum absorption peak of the colored species was at 515 nm. It is shifted from 420 nm of ARS. Balance dialysis method, molar ratio method and double wavelengh method were adopted to investigate the association formation. The following results were obtained:binding number n1=13, n1=45; apparent molar absorptivity εB1=5.89×103 L/(mol·cm), εB2=4.68×103 L/(mol·cm); accumulative equilibrium constant β1=5.27×104 L/mol, β2=3.54×105 L/mol. It is found that combination of BSP with ARS conforms to Scatchard model and the first type binding number completely conform to functional atom number of BSP activity center in its space conformation. It is suggested that the combination between BSP and ARS is due to the electrostatic force(primary action force) and hydrophobic force.
2004, 21(5): 464-468
Abstract:
Two sulphonated phosphine ligands [(Et3NH)2][Ph2PCH2N(CH2CH2SO3)2(2a)and [(Et3NH)2] [O3SCH2CH2N(CH2PPh2)CH2CH2N(CH2PPh2)CH2CH2SO3](2b) with greater water solubi-lity were synthesized by reaction of amines containing sulfo-group with [Ph2P(CH2OH)2]+Cl- and characterized by NMR, MS and IR. The solubility of ligand 2a was 0.21 g/mL(in water) and 0.29g/mL(in ethanol) at 25℃. For compound 2b, where the molar ratio of SO3H to Ph2P was more low, the solubility was 0.11 g/mL(in water) and 0.15 g/mL(in ethanol), respectively.
Two sulphonated phosphine ligands [(Et3NH)2][Ph2PCH2N(CH2CH2SO3)2(2a)and [(Et3NH)2] [O3SCH2CH2N(CH2PPh2)CH2CH2N(CH2PPh2)CH2CH2SO3](2b) with greater water solubi-lity were synthesized by reaction of amines containing sulfo-group with [Ph2P(CH2OH)2]+Cl- and characterized by NMR, MS and IR. The solubility of ligand 2a was 0.21 g/mL(in water) and 0.29g/mL(in ethanol) at 25℃. For compound 2b, where the molar ratio of SO3H to Ph2P was more low, the solubility was 0.11 g/mL(in water) and 0.15 g/mL(in ethanol), respectively.
2004, 21(5): 469-474
Abstract:
A new acidity point valence(δia) of non-hydrogen atom based on Randićs branching degree(δi) is derived. A novel topological index(m<F) of molecular tree and its trunk index(m<Fc), leaf index(m<Fx) are set up from δia. The 0Fx, 0Fc,1Fc and other structural parameters(,L,x',I) exhibit an excellent correlation to the acidity pKa of 38 carboxylic acids. The best linear equation of heptvariant regression is proposed:pKa= 11.409 33-1.243 270Fx-0.617 230Fc+0.097 001Fc-0.982 00xp+1.283 71L-0.200 47x'-0.862 10I, R=0.987 1, S=0.168. The model could be used effectively to predict the pKa values of carboxylic acids. Furthermore, a modified Jackknife test is used to validate the model robustness. On the basis of 12 structural parameters, a satisfactory equation of the pKa has been obtained, whose correlation coefficient(R) and mean error(S) were 0.988 6 and 0.116, respectively. The correlativity is better than the results obtained from comparative molecular field analysis(CoMFA) reported in the literature, where R and S were 0.988 and 0.121, respectively.
A new acidity point valence(δia) of non-hydrogen atom based on Randićs branching degree(δi) is derived. A novel topological index(m<F) of molecular tree and its trunk index(m<F
Synthesis,Characterization and Catalytic Behavior of Heteropolytungstates Containing Peroxozirconium
2004, 21(5): 475-478
Abstract:
Five heteropoly acid isomers α-K6[SiW11ZrO40]·xH2O, α-K6[SiW11(ZrO2)2+O39]·xH2O and βi-K6[SiW11(ZrO2)2++O39]·xH2O(βi=β1,β2,β3) were synthesized and characterized. The IR, UV spectrometry, polarography and chemical titration confirmed the existence of ZrO2 groups in the complexes. All 183W NMR spectra revealed the Keggin structure of anions in the compounds. The catalytic epoxidation of maleic acid showed that the catalytic activity of these complexes is higher than those of their corresponding complexes not containing peroxyion. Meanwhile the activity of β isomer is higher than that of α isomer.
Five heteropoly acid isomers α-K6[SiW11ZrO40]·xH2O, α-K6[SiW11(ZrO2)2+O39]·xH2O and βi-K6[SiW11(ZrO2)2++O39]·xH2O(βi=β1,β2,β3) were synthesized and characterized. The IR, UV spectrometry, polarography and chemical titration confirmed the existence of ZrO2 groups in the complexes. All 183W NMR spectra revealed the Keggin structure of anions in the compounds. The catalytic epoxidation of maleic acid showed that the catalytic activity of these complexes is higher than those of their corresponding complexes not containing peroxyion. Meanwhile the activity of β isomer is higher than that of α isomer.
2004, 21(5): 479-482
Abstract:
A kind of novel naphthylporphyrin-anthraquinone compound and its copper complex were synthesized from 5-(4-hydroxyphenyl)-10,15,20-trinaphthyl-porphyrin and characterized by 1H NMR, IR, FAB-MS, elemental analysis and UV-Vis spectrometry. The results show that the absorption spectra of these compounds are bathochromic by 5~10 nm in comparison with tetraphenylporphyrin and the absorption wavelength of compound Ⅰ is bathochromic with increase of the solvent polarity. Fluorescence quenching occurrs due to the intramolecular photoinduced electron transfer in the naphthylporphyrin-anthraquinone molecule with quenching percentage up to 22%.
A kind of novel naphthylporphyrin-anthraquinone compound and its copper complex were synthesized from 5-(4-hydroxyphenyl)-10,15,20-trinaphthyl-porphyrin and characterized by 1H NMR, IR, FAB-MS, elemental analysis and UV-Vis spectrometry. The results show that the absorption spectra of these compounds are bathochromic by 5~10 nm in comparison with tetraphenylporphyrin and the absorption wavelength of compound Ⅰ is bathochromic with increase of the solvent polarity. Fluorescence quenching occurrs due to the intramolecular photoinduced electron transfer in the naphthylporphyrin-anthraquinone molecule with quenching percentage up to 22%.
2004, 21(5): 483-487
Abstract:
Homopolymer of dimethyldiallylammonium chloride(PDMDAAC) with high intrinsic viscosity was obtained by using water-soluble azo initiators 2,2'-azobis-isobutylamidine dihydrochloride(AIBA·2HCl) and 2,2'-azobis(4-cyano) pentanoic acid(SN).The influences of monomer mass fraction, initiator concentration, composite initiator and chelating agent concentration on the synthesis have been studied. The results indicated that AIBA·2HCl was a high efficient initiator. At the condition of ω(PDMDAAC)=65%~70%, c(AIBA·2HCl)=2.0×10-2 mol/L and c(EDTA)=4×10-4~7.5×10-4 mol/L, the intrinsic viscosity of PDMDAAC was 2.10 dL/g; when polymerization was inittated by mixture of SN and AIBA·2HCl, in mass ratio of m(SN):m(AIBA·2HCl)=3:7, the intrinsic viscosity of the PPDMDAAC was up to 2.25 dL/g.
Homopolymer of dimethyldiallylammonium chloride(PDMDAAC) with high intrinsic viscosity was obtained by using water-soluble azo initiators 2,2'-azobis-isobutylamidine dihydrochloride(AIBA·2HCl) and 2,2'-azobis(4-cyano) pentanoic acid(SN).The influences of monomer mass fraction, initiator concentration, composite initiator and chelating agent concentration on the synthesis have been studied. The results indicated that AIBA·2HCl was a high efficient initiator. At the condition of ω(PDMDAAC)=65%~70%, c(AIBA·2HCl)=2.0×10-2 mol/L and c(EDTA)=4×10-4~7.5×10-4 mol/L, the intrinsic viscosity of PDMDAAC was 2.10 dL/g; when polymerization was inittated by mixture of SN and AIBA·2HCl, in mass ratio of m(SN):m(AIBA·2HCl)=3:7, the intrinsic viscosity of the PPDMDAAC was up to 2.25 dL/g.
2004, 21(5): 488-492
Abstract:
The decomposition of ammonium perchlorate(AP) in the presence of nanometer metal powders has been investigated by DTA. The results show that nanometer Cu, Ni and Al powders clearly decreased the high decomposition temperature of AP by 130.2, 112.9 and 51.8℃ respectively, as compared with that of AP without metal powder, showing good catalytic effects on the higher temperature decomposition of AP. Nanometer Cu powder also obviously decrases the low decomposition temperature of AP by 35.1℃, whereas the nanometer Ni and Al powders increased it. The catalytic effects of micron metal powders on the high temperature decomposition of AP are less than that of nanometer metal powders, but all the micron metal powders decrease the low decomposition temperature of AP.
The decomposition of ammonium perchlorate(AP) in the presence of nanometer metal powders has been investigated by DTA. The results show that nanometer Cu, Ni and Al powders clearly decreased the high decomposition temperature of AP by 130.2, 112.9 and 51.8℃ respectively, as compared with that of AP without metal powder, showing good catalytic effects on the higher temperature decomposition of AP. Nanometer Cu powder also obviously decrases the low decomposition temperature of AP by 35.1℃, whereas the nanometer Ni and Al powders increased it. The catalytic effects of micron metal powders on the high temperature decomposition of AP are less than that of nanometer metal powders, but all the micron metal powders decrease the low decomposition temperature of AP.
2004, 21(5): 493-497
Abstract:
The quaternary ammonium cellulose nitrate(QACN) was prepared by reacting cellulose nitrate(with degree of subtitution 1.15) with 3-chloro-2-hydroxylpropyl-trimethylammonium chloride(CHPA). The substitution degree of nitrate in QACN was 1.03 and that of NR4 was 0.38. The structure of QACN has been confirmed by elemental analysis, IR, 13C NMR, and XPS. It has a good adsorption property for creatinine. The equilibrium adsorption ratio of QACN for creatinine was 49% at 37℃, at dosage of 0.5 g, pH=7 and creatinine concentration of 60 mg/L in 25 mL dialysate. The equilibrium time was 4 h.
The quaternary ammonium cellulose nitrate(QACN) was prepared by reacting cellulose nitrate(with degree of subtitution 1.15) with 3-chloro-2-hydroxylpropyl-trimethylammonium chloride(CHPA). The substitution degree of nitrate in QACN was 1.03 and that of NR4
2004, 21(5): 498-501
Abstract:
A novel cationic natural organic polymeric flocculant DXSL-I was prepared using corn-core-powder(QCCP, φ<0.147 mm) as matrix and triethylamino-epoxypropane(TAEP prepared from triethylamine and epichlorohydrin) as cationic reagent. The reaction was initiated by H2O2-FeSO4. The preparation conditions were optimized as follows:2.0 g QCCP was at first alkalified with 0.6 g NaOH in 8 mL H2O(0.1%(mass fraction) NaCl as depressor) at 40℃ in 60 min, then etherified with 8 mL TAEP at 55℃ for 3.5 h in the presence of ω(H2O2-FeSO4) 0.01%. Experiment showed that the efficiency of etherization was 83%. The transparency of Kaoline turbid solution treated by drops of DXSL-Ⅰ over 5 min could reach up to 95% in the midst.
A novel cationic natural organic polymeric flocculant DXSL-I was prepared using corn-core-powder(QCCP, φ<0.147 mm) as matrix and triethylamino-epoxypropane(TAEP prepared from triethylamine and epichlorohydrin) as cationic reagent. The reaction was initiated by H2O2-FeSO4. The preparation conditions were optimized as follows:2.0 g QCCP was at first alkalified with 0.6 g NaOH in 8 mL H2O(0.1%(mass fraction) NaCl as depressor) at 40℃ in 60 min, then etherified with 8 mL TAEP at 55℃ for 3.5 h in the presence of ω(H2O2-FeSO4) 0.01%. Experiment showed that the efficiency of etherization was 83%. The transparency of Kaoline turbid solution treated by drops of DXSL-Ⅰ over 5 min could reach up to 95% in the midst.
2004, 21(5): 502-505
Abstract:
Acetyl galactopyranosides were obtained by the reaction of 3-acetyl tropolone and 3-acetamido-tropolone with acetyl-α-D-galactopyranosyl bromide,respectively, using AgCO3 as catalyst. Because of the tautomerism of tropolone molecule there were two isomeric products corresponding to the two starting materials prepared by Koenigs-Knorr glycosidation. The structure of these products was confirmed by elemental analysis, IR and 1H NMR spectra. The results confirmed the products obtained were acetyl galactopyranosides compounds containing tropolone moiety.
Acetyl galactopyranosides were obtained by the reaction of 3-acetyl tropolone and 3-acetamido-tropolone with acetyl-α-D-galactopyranosyl bromide,respectively, using AgCO3 as catalyst. Because of the tautomerism of tropolone molecule there were two isomeric products corresponding to the two starting materials prepared by Koenigs-Knorr glycosidation. The structure of these products was confirmed by elemental analysis, IR and 1H NMR spectra. The results confirmed the products obtained were acetyl galactopyranosides compounds containing tropolone moiety.
2004, 21(5): 506-508
Abstract:
A cationic gemini surfactant 10-2-10, 1,2-ethane bis(decyl dimethyl ammonium bromide) was synthesized, and the interactions in a mixture of the cationic gemini surfactant with a water-soluble polymer polyvinyl alcohol(PVA) were investigated by means of viscosity, electric conductivity, surface tension and ultraviolet spectrum measurements. The results showed that PVA displays viscosity behavior of polyelectrolyte-electroviscous effect in an aqueous solution with gemini surfactant 10-2-10 due to the molecular interaction between the polymer and the surfactant. The maximum UV absorption wavelength of polymer-surfactant solution shifted to higher wavelength compared with that of the surfactant, and the conductivity of polymer-surfactant solution increased with increase in concentration of PVA in a certain surfactant concentration. In addition, surface tension of gemini surfactant 10-2-10 solution decreased in the presence of PVA and its critical micelle concentration decreased from 5.9 mmol/L to 4.8 mmol/L in the presence of 1.25×10-3 g/mL PVA.
A cationic gemini surfactant 10-2-10, 1,2-ethane bis(decyl dimethyl ammonium bromide) was synthesized, and the interactions in a mixture of the cationic gemini surfactant with a water-soluble polymer polyvinyl alcohol(PVA) were investigated by means of viscosity, electric conductivity, surface tension and ultraviolet spectrum measurements. The results showed that PVA displays viscosity behavior of polyelectrolyte-electroviscous effect in an aqueous solution with gemini surfactant 10-2-10 due to the molecular interaction between the polymer and the surfactant. The maximum UV absorption wavelength of polymer-surfactant solution shifted to higher wavelength compared with that of the surfactant, and the conductivity of polymer-surfactant solution increased with increase in concentration of PVA in a certain surfactant concentration. In addition, surface tension of gemini surfactant 10-2-10 solution decreased in the presence of PVA and its critical micelle concentration decreased from 5.9 mmol/L to 4.8 mmol/L in the presence of 1.25×10-3 g/mL PVA.
2004, 21(5): 509-511
Abstract:
The solubilities and properties such as density, electrical conductivity and pH of the solutions in the quaternary system K2CO3-Na2CO3-Li2CO3-H2O at 288 K have been studied by isothermal equilibrium method. Based on the solubility data, the phase diagram of the system was obtained, which comprises two invariant points E and F and five uninvariant curves E3E, E4E, E1F, E2F and EF. The four stationary phases in crystallization regions are K2CO3·3/2H2O, Na2CO3·10H2O, NaKCO3·6H2O and Li2CO3. The composition of the solution corresponding to E is ω(K2CO3)=51.34%, ω(Na2CO3)=2.94%, ω(Li2CO3)=0.21% and the equilibrium solids are K2CO3· 3/2H2O+NaKCO3·6H2O+Li2CO3. The composition of the solution for F is ω(K2CO3)=15.19%, ω(Na2CO3)=13.62%, ω(Li2CO3)=0.70% and the equilibrium solids are Na2CO3· 10H2O+NaKCO3·6H2O+Li2CO3. Potassium carbonate has strong salting-out effect on Na2CO3 and Li2CO3. The physico-chemical properties of the system have been discussed briefly.
The solubilities and properties such as density, electrical conductivity and pH of the solutions in the quaternary system K2CO3-Na2CO3-Li2CO3-H2O at 288 K have been studied by isothermal equilibrium method. Based on the solubility data, the phase diagram of the system was obtained, which comprises two invariant points E and F and five uninvariant curves E3E, E4E, E1F, E2F and EF. The four stationary phases in crystallization regions are K2CO3·3/2H2O, Na2CO3·10H2O, NaKCO3·6H2O and Li2CO3. The composition of the solution corresponding to E is ω(K2CO3)=51.34%, ω(Na2CO3)=2.94%, ω(Li2CO3)=0.21% and the equilibrium solids are K2CO3· 3/2H2O+NaKCO3·6H2O+Li2CO3. The composition of the solution for F is ω(K2CO3)=15.19%, ω(Na2CO3)=13.62%, ω(Li2CO3)=0.70% and the equilibrium solids are Na2CO3· 10H2O+NaKCO3·6H2O+Li2CO3. Potassium carbonate has strong salting-out effect on Na2CO3 and Li2CO3. The physico-chemical properties of the system have been discussed briefly.
2004, 21(5): 512-514
Abstract:
Polymer nanoemulsion was prepared by high shear emulsion polymerization and its particle diameter was determined. The results showed that the particle diameter reduced with the increase of reaction temperature, initiator concentration, water content and stirring speed. The optimal ratio of constituents of nanopaints each to other was obtained by orthogonal factorization experiments, and the nanopaint with appropiate viscosity and excellent storage stability was prepared when it contains 0.2% of dispersant, 4.7% of alkaline swelling polyacrylate emulsion thickener and 1.4% of nonionic associative polyurethane thickener.
Polymer nanoemulsion was prepared by high shear emulsion polymerization and its particle diameter was determined. The results showed that the particle diameter reduced with the increase of reaction temperature, initiator concentration, water content and stirring speed. The optimal ratio of constituents of nanopaints each to other was obtained by orthogonal factorization experiments, and the nanopaint with appropiate viscosity and excellent storage stability was prepared when it contains 0.2% of dispersant, 4.7% of alkaline swelling polyacrylate emulsion thickener and 1.4% of nonionic associative polyurethane thickener.
2004, 21(5): 515-517
Abstract:
Aragonite calcium carbonate whisker was prepared by thermal decomposition of Ca(HCO3)2 in aqueous solution in the presence of chloride salts. The influences of reaction temperature, time and concentrations of CaCl2, MgCl2 and KCl on the morphology of CaCO3 whiskers were studied. The structure characteristics of CaCO3 whiskers were analyzed by XRD and SEM. The results indicate that the optimum conditions are 80~100℃, 50~60 min and the suitable concentrations of Ca(HCO3)2, KCl, MgCl2, CaCl2 are 6.0 mmol/L, 14.0 mmol/L, 1.0 mmol/L, 1.5 mmol/L respectively. The purity of the whiskers is 99.53% and the average aspect ratio is 24.1.
Aragonite calcium carbonate whisker was prepared by thermal decomposition of Ca(HCO3)2 in aqueous solution in the presence of chloride salts. The influences of reaction temperature, time and concentrations of CaCl2, MgCl2 and KCl on the morphology of CaCO3 whiskers were studied. The structure characteristics of CaCO3 whiskers were analyzed by XRD and SEM. The results indicate that the optimum conditions are 80~100℃, 50~60 min and the suitable concentrations of Ca(HCO3)2, KCl, MgCl2, CaCl2 are 6.0 mmol/L, 14.0 mmol/L, 1.0 mmol/L, 1.5 mmol/L respectively. The purity of the whiskers is 99.53% and the average aspect ratio is 24.1.
2004, 21(5): 518-520
Abstract:
The relationship between the reduced viscosity and concentation of sulfonated styrene-isoprene-styrene triblock copolymer(SSIS) and its ionomers in toluene and toluene/methanol solutions were studied. The intrinsic viscosity [η\] was calculated. The results show that SSIS tends to form an intra-molecular chain interaction and form more enclosed molecular chain with a lower reduced viscosity and intrinsic viscosity when the sulfonation degree x(SO3H) decreased. A change of interaction from intra-to inter-molecular chain was observed, and the intrinsic viscosity improved from 0.641 dL/g to 0.656 dL/g by increasing the sulfonation degree from 3.95% to 7.36% due to the chain combination. This also make the size of molecular chain of SSIS larger than SIS. Although be a precipitant for SIS, a few amounts of methanol can change the solubility of SSIS in toluene by destroying the combination of molecular chain. Lanthanum ionomers showed a lower reduced viscosity as compared with sodium and zinc ionomers.
The relationship between the reduced viscosity and concentation of sulfonated styrene-isoprene-styrene triblock copolymer(SSIS) and its ionomers in toluene and toluene/methanol solutions were studied. The intrinsic viscosity [η\] was calculated. The results show that SSIS tends to form an intra-molecular chain interaction and form more enclosed molecular chain with a lower reduced viscosity and intrinsic viscosity when the sulfonation degree x(SO3H) decreased. A change of interaction from intra-to inter-molecular chain was observed, and the intrinsic viscosity improved from 0.641 dL/g to 0.656 dL/g by increasing the sulfonation degree from 3.95% to 7.36% due to the chain combination. This also make the size of molecular chain of SSIS larger than SIS. Although be a precipitant for SIS, a few amounts of methanol can change the solubility of SSIS in toluene by destroying the combination of molecular chain. Lanthanum ionomers showed a lower reduced viscosity as compared with sodium and zinc ionomers.
2004, 21(5): 521-523
Abstract:
2,2'-Dichlorohydrazobenzene(DHB) was prepared in two steps. o-Chloronitrobenzene(OCNB) was at first reduced to 2,2'-dichloroazoxybenzene(DOB) in aqueous medium using 2,3-dichloro-1,4-naphthaquinone(OCNQ) as catalyst with yield of 99.4%, mp 53~56℃; DOB was then reduced by formaldehyde to give DHB in aqueous alkaline methanol with yield of 76%, 49% higher than reported, mp 82~83.5℃. DHB could be rearranged to 3,3'-dichlorobenzidine in strong acidic medium with yield 91.8%, mp 132~134℃.
2,2'-Dichlorohydrazobenzene(DHB) was prepared in two steps. o-Chloronitrobenzene(OCNB) was at first reduced to 2,2'-dichloroazoxybenzene(DOB) in aqueous medium using 2,3-dichloro-1,4-naphthaquinone(OCNQ) as catalyst with yield of 99.4%, mp 53~56℃; DOB was then reduced by formaldehyde to give DHB in aqueous alkaline methanol with yield of 76%, 49% higher than reported, mp 82~83.5℃. DHB could be rearranged to 3,3'-dichlorobenzidine in strong acidic medium with yield 91.8%, mp 132~134℃.
2004, 21(5): 524-526
Abstract:
The water-soluble organic phosphate compounds as lubricant were synthesied and analyzed by IR spectrometry. The tribological properties of the compounds were evaluated in a self-made four-ball tester. It is found that the lubrication properties of the water-soluble organic phosphate are affected by the alkyl chain length of the organic lubricant and the longer the chain with the hydrophobic group, the better the lubrication property of the phosphate. The highest load capacity of the phosphate was 676 N, and the wear scar diameter on the four-ball tester was 0.46 mm. The SEM and EDAX results indicate that phosphors are adsorbed on the worn surface in the form of ironic phosphate which provides high antiwear properties.
The water-soluble organic phosphate compounds as lubricant were synthesied and analyzed by IR spectrometry. The tribological properties of the compounds were evaluated in a self-made four-ball tester. It is found that the lubrication properties of the water-soluble organic phosphate are affected by the alkyl chain length of the organic lubricant and the longer the chain with the hydrophobic group, the better the lubrication property of the phosphate. The highest load capacity of the phosphate was 676 N, and the wear scar diameter on the four-ball tester was 0.46 mm. The SEM and EDAX results indicate that phosphors are adsorbed on the worn surface in the form of ironic phosphate which provides high antiwear properties.
2004, 21(5): 527-529
Abstract:
A novel Schiff base was synthesized by the reaction of terephthaldehyde with thiosemicarbazide. The structure was confirmed by elemental analysis, IR, UV-vis,1H NMR and X-ray single crystal diffractometry and the composition of the compound is identified as C16H26N8O2S2. The preliminary anti-bacterial activity tests showed the Schiff base possesses an inhibition activity towards Escherichia Coli, Staphylococcus aureus and Bacillus subtilis.
A novel Schiff base was synthesized by the reaction of terephthaldehyde with thiosemicarbazide. The structure was confirmed by elemental analysis, IR, UV-vis,1H NMR and X-ray single crystal diffractometry and the composition of the compound is identified as C16H26N8O2S2. The preliminary anti-bacterial activity tests showed the Schiff base possesses an inhibition activity towards Escherichia Coli, Staphylococcus aureus and Bacillus subtilis.
2004, 21(5): 530-531
Abstract:
4-Cyanopyridine was at first catalytically hydrolyzed to give isonicotinamide in the presence of Mg-Fe oxides with yield 92%. 4-Aminopyridine was obtained from isonicotinamide in yield of 83%~85% by Hofmann reaction using iodo-benzene as catalyst. All of the reaction were monitored by TLC and the products were confirmed by IR, NMR and melting point determination.
4-Cyanopyridine was at first catalytically hydrolyzed to give isonicotinamide in the presence of Mg-Fe oxides with yield 92%. 4-Aminopyridine was obtained from isonicotinamide in yield of 83%~85% by Hofmann reaction using iodo-benzene as catalyst. All of the reaction were monitored by TLC and the products were confirmed by IR, NMR and melting point determination.
2004, 21(5): 532-534
Abstract:
Lipophilic epoxy resin E-44 is introduced into hydrophilic PEG-6000 molecule through nucleophilic addition reaction between the epoxy group and the hydroxyl group under catalysis of boron tri-fluoride etherate[C2H5]2O·BF3]to syn the size aspeciale mulsifier EP 1 for epoxyres in.EP-1ha a fair solubility in water and acertainsur faceactivity.Its surfacetensio non water is 44m N/matcritical micelle concentration (CMC).A high mechanical stablee mulsion with averageparticle size of 107.3nm has been prepare dusingEP 1 as anemulsi fier by phasein versione mulsionprocess and there from a nanometer emulsion with average particle size of 91.8 nm has been obtained.
Lipophilic epoxy resin E-44 is introduced into hydrophilic PEG-6000 molecule through nucleophilic addition reaction between the epoxy group and the hydroxyl group under catalysis of boron tri-fluoride etherate[C2H5]2O·BF3]to syn the size aspeciale mulsifier EP 1 for epoxyres in.EP-1ha a fair solubility in water and acertainsur faceactivity.Its surfacetensio non water is 44m N/matcritical micelle concentration (CMC).A high mechanical stablee mulsion with averageparticle size of 107.3nm has been prepare dusingEP 1 as anemulsi fier by phasein versione mulsionprocess and there from a nanometer emulsion with average particle size of 91.8 nm has been obtained.
2004, 21(5): 535-537
Abstract:
The calcium alginate gel beads(CAGB) are modified via graft copolymerization with acrylonitrile(AN). It is found that the grafting yield achieved 799% when 5.0 g CAGB(in diameter of 3.2 mm) is mixed with 0.033 9 mol/L K2S2O8 for 35 min at 51℃ and copolymerized with 2.85 mol/L AN for 4 h. The structure of CAGB-g-PAN is verified with FTIR. The compactness of CAGB and modified CAGB is investigated with fluorometry. It is found that the compactness of the gel beads is increased with the grafting yield. Modified CAGBs keep their integrity in the electrolyte solutions that are capable of decomposition of CAGB, indicating the stability of CAGB is greatly enhanced.
The calcium alginate gel beads(CAGB) are modified via graft copolymerization with acrylonitrile(AN). It is found that the grafting yield achieved 799% when 5.0 g CAGB(in diameter of 3.2 mm) is mixed with 0.033 9 mol/L K2S2O8 for 35 min at 51℃ and copolymerized with 2.85 mol/L AN for 4 h. The structure of CAGB-g-PAN is verified with FTIR. The compactness of CAGB and modified CAGB is investigated with fluorometry. It is found that the compactness of the gel beads is increased with the grafting yield. Modified CAGBs keep their integrity in the electrolyte solutions that are capable of decomposition of CAGB, indicating the stability of CAGB is greatly enhanced.
2004, 21(5): 538-540
Abstract:
A novel Gemini surfactant bis[N,N'-(dodecanoylamino)ethyl]triethylenediamine bromide(BDEDE) was synthesized from ethyl bromide and bis(2-dodecanoylaminoethyl) ethylene diamine(BDEE), the latter was prepared from lauric acid and N,N'-bis(2-aminoethyl) ethylenediamine. The structure of the Gemini surfactant was characterized by elemental analysis, IR, 1H NMR and 13C NMR. Its critical micelle concentration(0.105 mmol/L) and γcmc(31.0 mN/m) were determined. The cmc value of Gemini surfactant decreased by appoximately two orders of magnitude than cmc of dodecyltrimethylammonium bromide.
A novel Gemini surfactant bis[N,N'-(dodecanoylamino)ethyl]triethylenediamine bromide(BDEDE) was synthesized from ethyl bromide and bis(2-dodecanoylaminoethyl) ethylene diamine(BDEE), the latter was prepared from lauric acid and N,N'-bis(2-aminoethyl) ethylenediamine. The structure of the Gemini surfactant was characterized by elemental analysis, IR, 1H NMR and 13C NMR. Its critical micelle concentration(0.105 mmol/L) and γcmc(31.0 mN/m) were determined. The cmc value of Gemini surfactant decreased by appoximately two orders of magnitude than cmc of dodecyltrimethylammonium bromide.
