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2004 Volume 21 Issue 1
2004, 21(1): 1-5
Abstract:
The research progresses of inflluence of the shear flow on the phase behavior of polymer blends are reviewed in three aspects:thermodynamic theory, experimental methods and influencing factors on the miscibility of polymer blends under shear flow field. The thermodynamic theory which is wildly used to predict the phase behavior of polymer blends under shear flow field. The fundamentals, merits, drawbacks and applications of various in-situ measuring methods were stressed. The dependence of the phase behavior of polymer blends on shear rate, shear stress, temperature and fraction of components was summed up in detail. The existed problems and trends in this research field are discussed briefly.
The research progresses of inflluence of the shear flow on the phase behavior of polymer blends are reviewed in three aspects:thermodynamic theory, experimental methods and influencing factors on the miscibility of polymer blends under shear flow field. The thermodynamic theory which is wildly used to predict the phase behavior of polymer blends under shear flow field. The fundamentals, merits, drawbacks and applications of various in-situ measuring methods were stressed. The dependence of the phase behavior of polymer blends on shear rate, shear stress, temperature and fraction of components was summed up in detail. The existed problems and trends in this research field are discussed briefly.
2004, 21(1): 6-11
Abstract:
AAO template has a highly ordered nanoporous array with adjustable and controllable pore diameter ranged in 5 nm to 20 nm. It has been used to prepare nanoparticle arrays, nanosized cables, nanoscale "sandwich" structures, nanotubes and nanowires of metals, nonmetals, semiconductors, conductive polymers and so on. These nanomaterials not only are of theoretical interest but also have potential technological applications in optics, electronics, magnetism and catalysis. In this paper the order of nanosized array pores, adjustment and control of pore diameter, assembling techniques, and the properties and applications of synthesized nanomaterials in AAO template are reviewed.
AAO template has a highly ordered nanoporous array with adjustable and controllable pore diameter ranged in 5 nm to 20 nm. It has been used to prepare nanoparticle arrays, nanosized cables, nanoscale "sandwich" structures, nanotubes and nanowires of metals, nonmetals, semiconductors, conductive polymers and so on. These nanomaterials not only are of theoretical interest but also have potential technological applications in optics, electronics, magnetism and catalysis. In this paper the order of nanosized array pores, adjustment and control of pore diameter, assembling techniques, and the properties and applications of synthesized nanomaterials in AAO template are reviewed.
2004, 21(1): 12-15
Abstract:
A facile synthesis of 1-dexoynojirimycin(DNJ), an important glycosidase inhibitor, using L-sorbose as the starting material. The hydroxy groups at C-2,3, of L-sorbose was selectively protected and an azide group was introduced at C-6, affording the key intermediate 6-deoxy-6-amino-L-sorbofuranose hydrochloride via catalytic hydrogenation and hydrolysis. The intermediate was converted into the target compound 1-deoxynojirimycin hydrochloride in a hydrogenation procedure, an epimer of DNJ being also generated but difficult to separate from the mixture in conventional ways. By means of benzyloxycarbonylation, N-benzyloxycarbonyl-1-deoxynojirimycin was isolated from the mixture.
A facile synthesis of 1-dexoynojirimycin(DNJ), an important glycosidase inhibitor, using L-sorbose as the starting material. The hydroxy groups at C-2,3, of L-sorbose was selectively protected and an azide group was introduced at C-6, affording the key intermediate 6-deoxy-6-amino-L-sorbofuranose hydrochloride via catalytic hydrogenation and hydrolysis. The intermediate was converted into the target compound 1-deoxynojirimycin hydrochloride in a hydrogenation procedure, an epimer of DNJ being also generated but difficult to separate from the mixture in conventional ways. By means of benzyloxycarbonylation, N-benzyloxycarbonyl-1-deoxynojirimycin was isolated from the mixture.
2004, 21(1): 16-19
Abstract:
A new method for the chiral separation of epinephrine is presented based on the β-cyclodextrin (β-CD)-sodium dodecyl sulfate(SDS)-micellar electrokinetic chromatography(MEKC) separation of the analytes combined with electrochemical detection using gold microelectrode at +0.65 V(vs. SCE). The effects of detection potential, concentration of β-cyclodextrin, concentration of sodium dodecyl sulfate, pH value of electrolyte and loading voltage were discussed. An attempt was made to elucidate the plausible mechanism of the chrial recognition.
A new method for the chiral separation of epinephrine is presented based on the β-cyclodextrin (β-CD)-sodium dodecyl sulfate(SDS)-micellar electrokinetic chromatography(MEKC) separation of the analytes combined with electrochemical detection using gold microelectrode at +0.65 V(vs. SCE). The effects of detection potential, concentration of β-cyclodextrin, concentration of sodium dodecyl sulfate, pH value of electrolyte and loading voltage were discussed. An attempt was made to elucidate the plausible mechanism of the chrial recognition.
2004, 21(1): 20-23
Abstract:
By heating diazo salt of corresponding ortho-amine of diphenyl ether in the presence of a mass fraction of 50% sulfuric acid, eight dibenzofuran and its derivatives (2a~2h, R=H,2-Cl,2-Br,2-Me, 2-Bu-t,2-OMe,3-OMe,4-Me) were synthesized in yields of 65%~70% and their structures were characterized by MS, HRMS, 1H NMR, 13CNMR, and elemental analysis. The conditions of the reaction were investigated, the optimum temperature of the reaction was 135℃. A possible mechanism was proposed.
By heating diazo salt of corresponding ortho-amine of diphenyl ether in the presence of a mass fraction of 50% sulfuric acid, eight dibenzofuran and its derivatives (2a~2h, R=H,2-Cl,2-Br,2-Me, 2-Bu-t,2-OMe,3-OMe,4-Me) were synthesized in yields of 65%~70% and their structures were characterized by MS, HRMS, 1H NMR, 13CNMR, and elemental analysis. The conditions of the reaction were investigated, the optimum temperature of the reaction was 135℃. A possible mechanism was proposed.
2004, 21(1): 24-27
Abstract:
The electrochemical oxidation of hypophosphite ions on polycrystaline Pt electrode in both acid and alkaline solutions has been studied by SNIFTIRS(Subtractively Normalized Interfacial FTIR Spectroscopy) and cyclic voltammetry, and compared with that on Ni electrode. From the in-situ IR spectra as a function of the electrode potentials, it was concluded that there is H2PO2(ad) on Pt as the adsorbed species besides adsorbed hydrogen. The product variety of hypophosphite oxidation on Pt depends on the electrode potentials and the pH values of solutions. At less positive potentials the product is H2PO3- in acidic solution or HPO3- in alkaline solution, and at more positive potentials the product is H3PO4 in acidic solution or PO43- in alkaline solution. The mechanism of hypophosphite oxidation on platinum electrode was discussed.
The electrochemical oxidation of hypophosphite ions on polycrystaline Pt electrode in both acid and alkaline solutions has been studied by SNIFTIRS(Subtractively Normalized Interfacial FTIR Spectroscopy) and cyclic voltammetry, and compared with that on Ni electrode. From the in-situ IR spectra as a function of the electrode potentials, it was concluded that there is H2PO2(ad) on Pt as the adsorbed species besides adsorbed hydrogen. The product variety of hypophosphite oxidation on Pt depends on the electrode potentials and the pH values of solutions. At less positive potentials the product is H2PO3- in acidic solution or HPO3- in alkaline solution, and at more positive potentials the product is H3PO4 in acidic solution or PO43- in alkaline solution. The mechanism of hypophosphite oxidation on platinum electrode was discussed.
2004, 21(1): 28-31
Abstract:
Approximately 170 L of water from Nanhu Lake and Yitonghe River(Changchun,China) have been taken as sample to develop surface coatings in the lab in order to investigate the adsorptive accumulation of Cd. The results indicate that the accumulation of Cd in the surface coatings increases regularly when the initial concentration of Cd is 0.05 mg/L. The great effects of Fe and Mn oxides on the accumulation of Cd in the developing process of natural surface coatings are observed.
Approximately 170 L of water from Nanhu Lake and Yitonghe River(Changchun,China) have been taken as sample to develop surface coatings in the lab in order to investigate the adsorptive accumulation of Cd. The results indicate that the accumulation of Cd in the surface coatings increases regularly when the initial concentration of Cd is 0.05 mg/L. The great effects of Fe and Mn oxides on the accumulation of Cd in the developing process of natural surface coatings are observed.
2004, 21(1): 32-35
Abstract:
The effect of ultrasonic energy on the degradation of methyl orange is found to be enhanced obviously in the presence of TiO2 catalyst under the acidic condition. Irradiation with the ultrasound of 25 kHz frequency and power input of 1.0 W/cm2 at pH=1.0, 98% methyl orange can be degradated within 90 min.
The effect of ultrasonic energy on the degradation of methyl orange is found to be enhanced obviously in the presence of TiO2 catalyst under the acidic condition. Irradiation with the ultrasound of 25 kHz frequency and power input of 1.0 W/cm2 at pH=1.0, 98% methyl orange can be degradated within 90 min.
2004, 21(1): 36-40
Abstract:
Carbon nitride films with high nitrogen content were obtained by cathodic electrodeposition onto glass substrates coated with indium tin oxide(ITO-coated glass) in solutions of dicyandiamide in acetonitrile. The XPS results showed that the maximum value of the N/C atomic ratio in the films was 1.22, close to the stoichiometric value of C3N4, and carbon-nitrogen bond forms were mainly C-N and C=N, as confirmed by FTIR spectroscopy. In Raman spectrum there are two peaks at 1 098 cm-1 and 1 950 cm-1 corresponding to C-N and C=N, which is seldom reported in literatures. The hardness and the Young's modulus of the sample obtained at 50℃、1 250 V were 11.31 GPa and 86 GPa, respectively. A polarization-competition reaction mechanism is proposed to interpret the results obtained.
Carbon nitride films with high nitrogen content were obtained by cathodic electrodeposition onto glass substrates coated with indium tin oxide(ITO-coated glass) in solutions of dicyandiamide in acetonitrile. The XPS results showed that the maximum value of the N/C atomic ratio in the films was 1.22, close to the stoichiometric value of C3N4, and carbon-nitrogen bond forms were mainly C-N and C=N, as confirmed by FTIR spectroscopy. In Raman spectrum there are two peaks at 1 098 cm-1 and 1 950 cm-1 corresponding to C-N and C=N, which is seldom reported in literatures. The hardness and the Young's modulus of the sample obtained at 50℃、1 250 V were 11.31 GPa and 86 GPa, respectively. A polarization-competition reaction mechanism is proposed to interpret the results obtained.
2004, 21(1): 41-44
Abstract:
The electrochemical behavior of ferrocene in the absence and presence of hydrogen peroxide in toluene-ethanol mixed solutions were investigated at a platinum electrode by cyclic voltammetry and AC impedance measurements. The results show that increasing toluene in the solution mixture leads to increase of both solution resistance and electrochemical reaction resistance of ferrocene at the Pt electrode. Ferricinium ion could react with hydrogen peroxide in the liquid phase. The electrode process is considered to be followed by catalytic EC(electron transfer-chemical reaction) mechanism.
The electrochemical behavior of ferrocene in the absence and presence of hydrogen peroxide in toluene-ethanol mixed solutions were investigated at a platinum electrode by cyclic voltammetry and AC impedance measurements. The results show that increasing toluene in the solution mixture leads to increase of both solution resistance and electrochemical reaction resistance of ferrocene at the Pt electrode. Ferricinium ion could react with hydrogen peroxide in the liquid phase. The electrode process is considered to be followed by catalytic EC(electron transfer-chemical reaction) mechanism.
2004, 21(1): 45-48
Abstract:
A super molecular complex[C6H11NH3]6[P2Mo18O62]·4H2O was synthesized by hydrothermal method and characterized by X-ray single crystal diffractometer. The compound belongs to monoclinic, with space group P21. Cell units:a=1.330 4(3) nm, b=2.791 0(6) nm, c=1.337 7(3) nm, β=118.72(3)°,Z=2, V=4.355 9 nm3, R=0.044 3, Rw=0.058 6. It consists of a Wells-Dawson-type heteropolyanion P2Mo18O626-, six protonized cyclohexylamine and four crystallization water molecules. Thermal analysis indicated it discomposes at 564 2℃.
A super molecular complex[C6H11NH3]6[P2Mo18O62]·4H2O was synthesized by hydrothermal method and characterized by X-ray single crystal diffractometer. The compound belongs to monoclinic, with space group P21. Cell units:a=1.330 4(3) nm, b=2.791 0(6) nm, c=1.337 7(3) nm, β=118.72(3)°,Z=2, V=4.355 9 nm3, R=0.044 3, Rw=0.058 6. It consists of a Wells-Dawson-type heteropolyanion P2Mo18O626-, six protonized cyclohexylamine and four crystallization water molecules. Thermal analysis indicated it discomposes at 564 2℃.
2004, 21(1): 49-53
Abstract:
The synthesis and structure characterization of a Schiff base prepared from 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone(PMBP) and m-chloroaniline and its Co(Ⅱ) complex are reported. X-ray diffraction analysis of the Co(Ⅱ) complex indicates the complex possesses four-coordinated structure with a distorted tetrahedral configuration from two O atoms of pyrazolone rings and two N atoms of m-chloroaniline moieties. The dihedral angles between the pyrazolone rings and their adjacent chalet ring planes are 2.47° and 1.69°, respectively, indicating a high degree of conjugation and electron delocalization. The ligand, Co(Ⅱ), Cu(Ⅱ) and Ni(Ⅱ) complexes have good bacteriostatic activities against E. coli and S. aureus, while the Co(Ⅱ) complex has the highest.
The synthesis and structure characterization of a Schiff base prepared from 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone(PMBP) and m-chloroaniline and its Co(Ⅱ) complex are reported. X-ray diffraction analysis of the Co(Ⅱ) complex indicates the complex possesses four-coordinated structure with a distorted tetrahedral configuration from two O atoms of pyrazolone rings and two N atoms of m-chloroaniline moieties. The dihedral angles between the pyrazolone rings and their adjacent chalet ring planes are 2.47° and 1.69°, respectively, indicating a high degree of conjugation and electron delocalization. The ligand, Co(Ⅱ), Cu(Ⅱ) and Ni(Ⅱ) complexes have good bacteriostatic activities against E. coli and S. aureus, while the Co(Ⅱ) complex has the highest.
2004, 21(1): 54-57
Abstract:
The transportation of Cd(Ⅱ) ions through a liquid membrane comsisted of hexadecylamine(RNH2), sorbital monooleate(Span 80) and kerosene has been studied as function of concentration of HCl, KI, hexadecylamine, Span 80 and NaOH in the feed, membrane and stripping solutions. The maximum transportation of Cd2+ was observed when the liquid membrane is consisted of outer phase 0.010~0.050 mol/L HCl and 0.020 mol/L KI, membrane phase 0.020~0.030 mol/L RNH2, 3.8%(mass fraction) Span 80 plus kerosene, and inner phase 0.010~0.030 mol/L NaOH. Cadmium ion could be separated completely from Fe(Ⅱ), Zn(Ⅱ), Co(Ⅱ), Ni(Ⅱ), Zn(Ⅱ), Al(Ⅲ), Cr(Ⅳ), Mn(Ⅱ). The transportation mechanism of the metal ions through the membrane has been discussed.
The transportation of Cd(Ⅱ) ions through a liquid membrane comsisted of hexadecylamine(RNH2), sorbital monooleate(Span 80) and kerosene has been studied as function of concentration of HCl, KI, hexadecylamine, Span 80 and NaOH in the feed, membrane and stripping solutions. The maximum transportation of Cd2+ was observed when the liquid membrane is consisted of outer phase 0.010~0.050 mol/L HCl and 0.020 mol/L KI, membrane phase 0.020~0.030 mol/L RNH2, 3.8%(mass fraction) Span 80 plus kerosene, and inner phase 0.010~0.030 mol/L NaOH. Cadmium ion could be separated completely from Fe(Ⅱ), Zn(Ⅱ), Co(Ⅱ), Ni(Ⅱ), Zn(Ⅱ), Al(Ⅲ), Cr(Ⅳ), Mn(Ⅱ). The transportation mechanism of the metal ions through the membrane has been discussed.
2004, 21(1): 58-63
Abstract:
Three β-alanine complexes with rare earths, {[Ln2(β-ala)6(H2O)4](ClO4)6·H2O}n(Ln=Nd(1), Gd(2), Er(3)), were synthesized and characterized by elemental analysis and IR. The crystal structures of three complexes were determined by X-ray diffraction method. All complexes crystallize in triclinic P1 space group with (1):a=1.2913(3)nm,b=2.1765(4)nm,c=0.93682(19)nm,α=99.07(3)°,β=96.91(3)°,γ=76.75(3)°,Z=2,Dc=1.988Mg/m3,F(000)=1502,R1=0.0547,wR2=0.1408;(2):a=1.2911(3)nm,b=2.1679(4)nm,c=0.92717(19)nm,α=98.94(3)°,β=97.00(3)°,γ=76.85(3)°,Z=2,Dc=2.050Mg/m3,F(000)=1518,R1=0.0522,wR2=0.1430;(3):a=1.2880(3)nm,b=2.1629(4)nm,c=0.92103(18)nm,α=98.77(3)°,β=97.29(3)°,γ=76.92(3)°,Z=2,Dc=2.100Mg/m3,F(000)=1534,R1=0.0615,wR2=0.1752 for Er complex. All three complexes have similar structures with one-dimensional infinite chain. The rare earth ion in the complexes is nine-coordinated in a distorted monocapped square antiprism geometry with seven oxygen atoms from six β-ala-nine molecules and two oxygen atoms from two water molecules. The average bond length of Ln-O(carboxyl) from Nd to Er complexes shortens with the increase of the atomic number of rare earth. The antibacterial activity of the complexes and β-alanine was tested. The complexes were more bacteriostatically active than the ligand.
Three β-alanine complexes with rare earths, {[Ln2(β-ala)6(H2O)4](ClO4)6·H2O}n(Ln=Nd(1), Gd(2), Er(3)), were synthesized and characterized by elemental analysis and IR. The crystal structures of three complexes were determined by X-ray diffraction method. All complexes crystallize in triclinic P1 space group with (1):a=1.2913(3)nm,b=2.1765(4)nm,c=0.93682(19)nm,α=99.07(3)°,β=96.91(3)°,γ=76.75(3)°,Z=2,Dc=1.988Mg/m3,F(000)=1502,R1=0.0547,wR2=0.1408;(2):a=1.2911(3)nm,b=2.1679(4)nm,c=0.92717(19)nm,α=98.94(3)°,β=97.00(3)°,γ=76.85(3)°,Z=2,Dc=2.050Mg/m3,F(000)=1518,R1=0.0522,wR2=0.1430;(3):a=1.2880(3)nm,b=2.1629(4)nm,c=0.92103(18)nm,α=98.77(3)°,β=97.29(3)°,γ=76.92(3)°,Z=2,Dc=2.100Mg/m3,F(000)=1534,R1=0.0615,wR2=0.1752 for Er complex. All three complexes have similar structures with one-dimensional infinite chain. The rare earth ion in the complexes is nine-coordinated in a distorted monocapped square antiprism geometry with seven oxygen atoms from six β-ala-nine molecules and two oxygen atoms from two water molecules. The average bond length of Ln-O(carboxyl) from Nd to Er complexes shortens with the increase of the atomic number of rare earth. The antibacterial activity of the complexes and β-alanine was tested. The complexes were more bacteriostatically active than the ligand.
2004, 21(1): 64-69
Abstract:
Ammonium nitrate(AN) is modified by calcium carbonate and magnesium sulfate, and then mixed with fuel oil and sawdust to make ANFO explosives. The explosives are initiated by No.8 detonator. The thermal decomposition of the modified AN and ANFO explosives have been studied by isothermal and DSC method. Specific surface area of the modified AN is determined to explain the detonation result. It is concluded that ANFO explosives can not be detonated with addition of 40% calcium carbonate or a mixture of 5% magnesium sulfate and 25% calcium carbonate. The double decomposition reaction between calcium carbonate and ammonium nitrate produces volatile gases such as NH3, H2O and CO2 and the decomposition rate is proportional to the calcium carbonate content, temperature and time. Although the thermal stability of ANFO explosives could be improved by calcium carbonate, requirement of detonation safety is not met by adding low amount of calcium carbonate into ammonium nitrate because the specific surface area of the modified AN is increased greatly by the volatilization from mentioned gases. The double salt formed from magnesium sulfate and ammonium nitrate could decrease the double decomposition reaction rate and reduce the detonation sensitivity of the modified AN.
Ammonium nitrate(AN) is modified by calcium carbonate and magnesium sulfate, and then mixed with fuel oil and sawdust to make ANFO explosives. The explosives are initiated by No.8 detonator. The thermal decomposition of the modified AN and ANFO explosives have been studied by isothermal and DSC method. Specific surface area of the modified AN is determined to explain the detonation result. It is concluded that ANFO explosives can not be detonated with addition of 40% calcium carbonate or a mixture of 5% magnesium sulfate and 25% calcium carbonate. The double decomposition reaction between calcium carbonate and ammonium nitrate produces volatile gases such as NH3, H2O and CO2 and the decomposition rate is proportional to the calcium carbonate content, temperature and time. Although the thermal stability of ANFO explosives could be improved by calcium carbonate, requirement of detonation safety is not met by adding low amount of calcium carbonate into ammonium nitrate because the specific surface area of the modified AN is increased greatly by the volatilization from mentioned gases. The double salt formed from magnesium sulfate and ammonium nitrate could decrease the double decomposition reaction rate and reduce the detonation sensitivity of the modified AN.
2004, 21(1): 70-75
Abstract:
A series of compounds containing tetrahydropyrimidinone ring were synthesized via condensation of asparagine t-butyl ester with aromatic aldehydes and amino acid chlorides. Conformational isomer ratio of the products and the activation free energy for conformational transformation between isomers were determined by dynamic 1H NMR spectroscopy. Reaction of the Fmoc-deprotected compounds containing tetrahydropyrimidinone ring with m-tolyl isocyanate provided some chlesystokynin analogues. Two endomorphin derivatives were also synthesized from a compound containing tetrahydropyrimidinone ring and the proper dipeptides.
A series of compounds containing tetrahydropyrimidinone ring were synthesized via condensation of asparagine t-butyl ester with aromatic aldehydes and amino acid chlorides. Conformational isomer ratio of the products and the activation free energy for conformational transformation between isomers were determined by dynamic 1H NMR spectroscopy. Reaction of the Fmoc-deprotected compounds containing tetrahydropyrimidinone ring with m-tolyl isocyanate provided some chlesystokynin analogues. Two endomorphin derivatives were also synthesized from a compound containing tetrahydropyrimidinone ring and the proper dipeptides.
2004, 21(1): 76-77
Abstract:
The gel and sol parts in epoxidized natural rubber(ENR) were separated with toluene and 2-pentanone, respectively, and their thermal aging behaviour were studied by FTIR spectrometry. The results indicate that the carbon-carbon double bonds and the epoxy bonds in both gel and sol are destroyed successively on aging process, accompanied with the occurance of the hydroxyl, ether, carbonyl of aldehyde and ketone groups. Along with prolonging the aging time, the aldehyde and ketone are further converted into ester structures. These changes of the functional groups demonstrate the gel is less thermostable than sol in ENR.
The gel and sol parts in epoxidized natural rubber(ENR) were separated with toluene and 2-pentanone, respectively, and their thermal aging behaviour were studied by FTIR spectrometry. The results indicate that the carbon-carbon double bonds and the epoxy bonds in both gel and sol are destroyed successively on aging process, accompanied with the occurance of the hydroxyl, ether, carbonyl of aldehyde and ketone groups. Along with prolonging the aging time, the aldehyde and ketone are further converted into ester structures. These changes of the functional groups demonstrate the gel is less thermostable than sol in ENR.
2004, 21(1): 78-80
Abstract:
Three kinds of phenolic resins have been synthesized at pH of 3 (with phenol/formaldehyde molar ratio of 1:0.75 catalyzed by oxalic acid), 8(with phenol/formaldehyde molar ratio of 1:1.4~1:2.4 catalyzed by KOH) and 14(with phenol/formaldehyde molar ratio of 1:1.2~1:1. 5 catalyzed by KOH), respectively. Investigation on the crosslinking reaction between phenolic resins and borate showed that resin synthesized at basic condition can chelated with borate quickly by passing CO2 through the resin sand. The results indicated that the cured casting of the resin synthesized at pH=14 possessed the highest mechanical strength.
Three kinds of phenolic resins have been synthesized at pH of 3 (with phenol/formaldehyde molar ratio of 1:0.75 catalyzed by oxalic acid), 8(with phenol/formaldehyde molar ratio of 1:1.4~1:2.4 catalyzed by KOH) and 14(with phenol/formaldehyde molar ratio of 1:1.2~1:1. 5 catalyzed by KOH), respectively. Investigation on the crosslinking reaction between phenolic resins and borate showed that resin synthesized at basic condition can chelated with borate quickly by passing CO2 through the resin sand. The results indicated that the cured casting of the resin synthesized at pH=14 possessed the highest mechanical strength.
2004, 21(1): 81-83
Abstract:
The fullerene compound CoC60(OH) has been prepared by the reaction of C60- anion with Co(Ⅱ) hydrous salt under nitrogen atmosphere and refluxing, and the title compound is characterized by FAB-MS, elemental analysis, FT-IR, XPS, UV-Vis and 1H NMR. The results prove the presence of C-Co and -OH groups in the resultant, and coovalent of Co bonding to C 60. The apparent charge distribution of the resultant appeaers to be CO2+C60-(OH)-, and there are three kinds of carbons with different electron density. The result of redox experiment indicates that the reduction potential of the compound is more negative than that of pure C60.
The fullerene compound CoC60(OH) has been prepared by the reaction of C60- anion with Co(Ⅱ) hydrous salt under nitrogen atmosphere and refluxing, and the title compound is characterized by FAB-MS, elemental analysis, FT-IR, XPS, UV-Vis and 1H NMR. The results prove the presence of C-Co and -OH groups in the resultant, and coovalent of Co bonding to C 60. The apparent charge distribution of the resultant appeaers to be CO2+C60-(OH)-, and there are three kinds of carbons with different electron density. The result of redox experiment indicates that the reduction potential of the compound is more negative than that of pure C60.
2004, 21(1): 84-86
Abstract:
The fluoro-polyester resins(F-UPR) were synthesized from tetrafluoro-o-phthahic acid, maleic acid and propanediol in order to introduce the fluorine atom into the unsaturated polyester resin(UPR) chains and improve their properties. The result indicated that the product has viscosity 0.21 Pa·s (25℃), about half of that of the common unsaturated polyester resins (0.39 Pa·s, 25℃) and the contact angle between water and cured F-UPR was 64°. The water-resistant ability and acid-resistant ability of the resin were improved. The spectral and thermo-stability test results of the F-UPR showed that the UV-curing process of F-UPR could be completed within 40 min and the total mass loss of UV-cured F-UPR was 94.6% with thermodestruction temperature being 373℃.
The fluoro-polyester resins(F-UPR) were synthesized from tetrafluoro-o-phthahic acid, maleic acid and propanediol in order to introduce the fluorine atom into the unsaturated polyester resin(UPR) chains and improve their properties. The result indicated that the product has viscosity 0.21 Pa·s (25℃), about half of that of the common unsaturated polyester resins (0.39 Pa·s, 25℃) and the contact angle between water and cured F-UPR was 64°. The water-resistant ability and acid-resistant ability of the resin were improved. The spectral and thermo-stability test results of the F-UPR showed that the UV-curing process of F-UPR could be completed within 40 min and the total mass loss of UV-cured F-UPR was 94.6% with thermodestruction temperature being 373℃.
2004, 21(1): 87-89
Abstract:
Four hydroxamic acid derivaties were prepared by reaction of hydroxylamine hydrochloride with dimethylphthalate, dimethylisophthalate, dimethylterephthalate and dimethylsebacate respectively and characterized by IR and elemental analysis. The antibacterial activities to Escherichia coli and Staphylococcus aureus of phthaloyl, isophthaloyl, terephthaloyl and sebacoyl hydroxamic acids have been determined using paper disc method. The result indicates that their antibacterial activities to Escherichia coli are better than that to Staphylococcus aureus and among them the sebacoyl hydroxamic acid is the best one. No linear correlation was observed between the antibacterial activities and the concentration of the compounds, each has its optimum antibacterial concentration.
Four hydroxamic acid derivaties were prepared by reaction of hydroxylamine hydrochloride with dimethylphthalate, dimethylisophthalate, dimethylterephthalate and dimethylsebacate respectively and characterized by IR and elemental analysis. The antibacterial activities to Escherichia coli and Staphylococcus aureus of phthaloyl, isophthaloyl, terephthaloyl and sebacoyl hydroxamic acids have been determined using paper disc method. The result indicates that their antibacterial activities to Escherichia coli are better than that to Staphylococcus aureus and among them the sebacoyl hydroxamic acid is the best one. No linear correlation was observed between the antibacterial activities and the concentration of the compounds, each has its optimum antibacterial concentration.
2004, 21(1): 90-92
Abstract:
The precursor Al(OEt)m (acac)n was prepared by using metal aluminium as sacrificing anode in the alcohol solution with Bu4NBr as supporting electrolyte, the temperature was controlled at 40~60℃. Metallic anode was dissolved and reduction reaction occurred on cathode. Nanocrystalline Al2O3 was prepared by direct hydrolysis of the electrolyte solution and sol-gel processing. FT-IR spectroscopy, TEM and XRD have been used to characterize the structure of the precursor and nanocrystalline Al2O3. The results showed that Al2O3 is of spiculate structure with size ranged in 5~10 nm.
The precursor Al(OEt)m (acac)n was prepared by using metal aluminium as sacrificing anode in the alcohol solution with Bu4NBr as supporting electrolyte, the temperature was controlled at 40~60℃. Metallic anode was dissolved and reduction reaction occurred on cathode. Nanocrystalline Al2O3 was prepared by direct hydrolysis of the electrolyte solution and sol-gel processing. FT-IR spectroscopy, TEM and XRD have been used to characterize the structure of the precursor and nanocrystalline Al2O3. The results showed that Al2O3 is of spiculate structure with size ranged in 5~10 nm.
2004, 21(1): 93-95
Abstract:
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used successfully to determine three kinds of bisphthalazinone phenyl ether aromatic polymers with 1,8,9-trihydroxyanthranene as matrix. The polymerization degree of the polymers were determined to be 1 to 17. The influence of deflection value used in MALDI-TOF MS method was discussed.
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used successfully to determine three kinds of bisphthalazinone phenyl ether aromatic polymers with 1,8,9-trihydroxyanthranene as matrix. The polymerization degree of the polymers were determined to be 1 to 17. The influence of deflection value used in MALDI-TOF MS method was discussed.
2004, 21(1): 96-97
Abstract:
Cellulose-tris(3,5-dimethylphenylcarbamate)(CDMPC) was used as a chiral stationary phase for resolution of theta-cypermethrin racemate by HPLC with n-hexane-isopropanol as mobile phase. The influences of isopropanol concentration in the mobile phase, temperature and the column length on the resolution were investigated. The resolution capacity was increased with decrease of isopropanol fraction in the mobile phase and the column temperature. The results revealed good chiralselectivity to theta-cypermethrin by HPLC using CDMPC as stationary phase.
Cellulose-tris(3,5-dimethylphenylcarbamate)(CDMPC) was used as a chiral stationary phase for resolution of theta-cypermethrin racemate by HPLC with n-hexane-isopropanol as mobile phase. The influences of isopropanol concentration in the mobile phase, temperature and the column length on the resolution were investigated. The resolution capacity was increased with decrease of isopropanol fraction in the mobile phase and the column temperature. The results revealed good chiralselectivity to theta-cypermethrin by HPLC using CDMPC as stationary phase.
2004, 21(1): 98-100
Abstract:
The total synthesis of 3,7-dimethyl-2-tridecanyl propionate, the active component of the sex pheromone of pine sawfly Diprion jingyuanensis is reported. The new synthesis process starts from 2-methyloctanal, then through hydroxyethylenation, transetherification, Claisen rearrangement, hydroxymethylation, hydrogenation to give 3,7-dimethyl-2-tridecanol. Esterification of 3,7-dimethyl-2-tridecanol affords 3,7-dimethyl-2-tridecanyl propionate.
The total synthesis of 3,7-dimethyl-2-tridecanyl propionate, the active component of the sex pheromone of pine sawfly Diprion jingyuanensis is reported. The new synthesis process starts from 2-methyloctanal, then through hydroxyethylenation, transetherification, Claisen rearrangement, hydroxymethylation, hydrogenation to give 3,7-dimethyl-2-tridecanol. Esterification of 3,7-dimethyl-2-tridecanol affords 3,7-dimethyl-2-tridecanyl propionate.
2004, 21(1): 101-103
Abstract:
The GeCl3, Ge(OH)3, GeO3 and GeO1/2 moieties have been introduced to sulfonyldianiline, carbamazepine and norfloxacin, respectively, to give four medicines containing germanium. The structures of the medicines prepared were characterized by IR, 1H NMR and elemental analysis. The biological tests showed that the new compounds have anticancerous activity, among them the compound prepared from sulfonyldianiline(2000-1) has inhibitory rate of 88.6% at dosage of 1×10-4 mol/L.
The GeCl3, Ge(OH)3, GeO3 and GeO1/2 moieties have been introduced to sulfonyldianiline, carbamazepine and norfloxacin, respectively, to give four medicines containing germanium. The structures of the medicines prepared were characterized by IR, 1H NMR and elemental analysis. The biological tests showed that the new compounds have anticancerous activity, among them the compound prepared from sulfonyldianiline(2000-1) has inhibitory rate of 88.6% at dosage of 1×10-4 mol/L.
2004, 21(1): 104-106
Abstract:
2-(5-Methyl-2-phenyl-4-oxazolyl)ethanol(1) was synthesized from L-aspartic acid via 5-step reactions; esterification, N-benzoylation, Dakin-West reaction, cyclizaction and reduction using LiAlH4 in about 31.2% overall yield. Reacting L-aspartic acid with methanol in 0℃ gave 72.6% L-aspartic acid β-methyl ester hydrochloride(2), which was benzoylated to give 82.0% N-benzoyl-L-aspartic acid β-methyl ester(3). Dakin-West reaction of 3 gave 74.4% methyl 3-benzamido-4-oxovalerate(4), which was cyclized in toluene by POCl3 to give 81.8% methyl 2-(5-methyl-2-phenyl-4-oxazolyl)acetate(5), the latter can easily convert to 1 by treatment with ether solution of LiAlH4 in yield of 86%. All the compounds were characterized by 1H NMR, IR and elemental analysis.
2-(5-Methyl-2-phenyl-4-oxazolyl)ethanol(1) was synthesized from L-aspartic acid via 5-step reactions; esterification, N-benzoylation, Dakin-West reaction, cyclizaction and reduction using LiAlH4 in about 31.2% overall yield. Reacting L-aspartic acid with methanol in 0℃ gave 72.6% L-aspartic acid β-methyl ester hydrochloride(2), which was benzoylated to give 82.0% N-benzoyl-L-aspartic acid β-methyl ester(3). Dakin-West reaction of 3 gave 74.4% methyl 3-benzamido-4-oxovalerate(4), which was cyclized in toluene by POCl3 to give 81.8% methyl 2-(5-methyl-2-phenyl-4-oxazolyl)acetate(5), the latter can easily convert to 1 by treatment with ether solution of LiAlH4 in yield of 86%. All the compounds were characterized by 1H NMR, IR and elemental analysis.
2004, 21(1): 107-108
Abstract:
A non-solvent synthesis procedure for the preparation of 2,2'-bipyrimidine, 4,4',6,6'-tetramethyl-2,2'-bipyrimidine and 4,4',6,6'-tetraphenyl-2,2'-bipyrimidine in high yields was developed using fresh copper powder as catalyst.
A non-solvent synthesis procedure for the preparation of 2,2'-bipyrimidine, 4,4',6,6'-tetramethyl-2,2'-bipyrimidine and 4,4',6,6'-tetraphenyl-2,2'-bipyrimidine in high yields was developed using fresh copper powder as catalyst.
