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2006 Volume 23 Issue 5
2006, 23(5): 465-470
Abstract:
The bisterpyridine ligands with oligo-PPV as spacer were designed and synthesized.Through step by step coordination,dinulear ruthenium complexes with terpyridine as the ligand were obtained.The complexes exhibited a strong metal to ligand charge transfer(MLCT) absorption peak at about 490 nm,while no emission was observed at ambient temperature because of the very short excited state time.All of the complexes,however,exhibited strong red emission (about 639~641 nm) at 77 K.The oxidation wave attributed to the ruthenium(Ⅱ) ion at about +1.25 V and the two reductive waves at about -1.15 V and(-1.38 V)(vs.Ag/AgCl) assigned to the terpyridine-based moiety were observed for the dinuclear ruthenium complexes.
The bisterpyridine ligands with oligo-PPV as spacer were designed and synthesized.Through step by step coordination,dinulear ruthenium complexes with terpyridine as the ligand were obtained.The complexes exhibited a strong metal to ligand charge transfer(MLCT) absorption peak at about 490 nm,while no emission was observed at ambient temperature because of the very short excited state time.All of the complexes,however,exhibited strong red emission (about 639~641 nm) at 77 K.The oxidation wave attributed to the ruthenium(Ⅱ) ion at about +1.25 V and the two reductive waves at about -1.15 V and(-1.38 V)(vs.Ag/AgCl) assigned to the terpyridine-based moiety were observed for the dinuclear ruthenium complexes.
2006, 23(5): 471-475
Abstract:
The burning behavior of 3 mm-thick PVC slabs(100 mm×100 mm) at different temperatures was studied with a cone calorimeter.A single equation model of mass loss rate vs time was simulated with a chemical kinetic method.The fitted results suggest that for PVC burning within a temperature range of 674~(892℃),the reacting kinetic equation can be described as-ln(1-a)=Ae-E/RTt;where the pre-exponential factor A and the average activation energy E are about 0.725 7 s-1and 45.2 kJ/mol,respectively.The simulation results are in reasonably good agreement with the experimental data.In the combustion process of PVC,the oxidation of hydrocarbon is the main oxygen consumption reaction,and the products are CO2 and CO,whose yields are both independent of the reaction temperature.
The burning behavior of 3 mm-thick PVC slabs(100 mm×100 mm) at different temperatures was studied with a cone calorimeter.A single equation model of mass loss rate vs time was simulated with a chemical kinetic method.The fitted results suggest that for PVC burning within a temperature range of 674~(892℃),the reacting kinetic equation can be described as-ln(1-a)=Ae-E/RTt;where the pre-exponential factor A and the average activation energy E are about 0.725 7 s-1and 45.2 kJ/mol,respectively.The simulation results are in reasonably good agreement with the experimental data.In the combustion process of PVC,the oxidation of hydrocarbon is the main oxygen consumption reaction,and the products are CO2 and CO,whose yields are both independent of the reaction temperature.
2006, 23(5): 476-479
Abstract:
Eleven novel target compounds were synthesized by the Michaelis-Becher reaction of substitutedphenylphosphinite with 2-chloro-5-chloromethylpyridine,their structures were confirmed by means of 1H NMR,31P NMR,MS,and elemental analysis.The results of preliminary bioassay show that all the new compounds display some fungicidal activities.
Eleven novel target compounds were synthesized by the Michaelis-Becher reaction of substitutedphenylphosphinite with 2-chloro-5-chloromethylpyridine,their structures were confirmed by means of 1H NMR,31P NMR,MS,and elemental analysis.The results of preliminary bioassay show that all the new compounds display some fungicidal activities.
2006, 23(5): 480-483
Abstract:
Water-soluble Phosphine Ligand PROPANa was synthesized by an improved method,in which Michael addition and the saponification reaction were completed in one-step with a yield of 87%.Its P⌒O coordinated cyclopalladated complex exhibits a high catalytic activity for Suzuki cross-coupling reaction between 4-bromotoluene and 4-fluorophenylboronic acid in a mixture of aqueous and organic solvents at room temperature.
Water-soluble Phosphine Ligand PROPANa was synthesized by an improved method,in which Michael addition and the saponification reaction were completed in one-step with a yield of 87%.Its P⌒O coordinated cyclopalladated complex exhibits a high catalytic activity for Suzuki cross-coupling reaction between 4-bromotoluene and 4-fluorophenylboronic acid in a mixture of aqueous and organic solvents at room temperature.
2006, 23(5): 484-488
Abstract:
Nanocomposites of 6F-Durene with covalently grafted polymethacrylate(PMA) side chains containing polyhedral oligomeric silsesquioxane(R7R'Si8O12 or POSS) units were prepared by means of the thermally-initiated free-radical graft polymerization of methacrylcyclopentyl-POSS(MA-POSS) with ozone-pretreated 6F-Durene.The chemical composition and the structure of the 6F-Durene with grafted methacrylcyclopentyl-POSS side chains(POSS/6F-Durene copolymers) were characterized by nuclear magnetic resonance(NMR),X-ray diffraction(XRD) and field-emission scanning electron microscopy(FESEM).The POSS/6FDurene nanocomposite films had both lower and tunable dielectric constants(ε's) in comparison with the pristine 6F-Durene films,with values between 2.0 and 2.5.
Nanocomposites of 6F-Durene with covalently grafted polymethacrylate(PMA) side chains containing polyhedral oligomeric silsesquioxane(R7R'Si8O12 or POSS) units were prepared by means of the thermally-initiated free-radical graft polymerization of methacrylcyclopentyl-POSS(MA-POSS) with ozone-pretreated 6F-Durene.The chemical composition and the structure of the 6F-Durene with grafted methacrylcyclopentyl-POSS side chains(POSS/6F-Durene copolymers) were characterized by nuclear magnetic resonance(NMR),X-ray diffraction(XRD) and field-emission scanning electron microscopy(FESEM).The POSS/6FDurene nanocomposite films had both lower and tunable dielectric constants(ε's) in comparison with the pristine 6F-Durene films,with values between 2.0 and 2.5.
2006, 23(5): 489-493
Abstract:
In order to study the thermal behavior in lithium-ion battery,the main heat generation process in the battery was studied by means of a C80 calorimeter.The main heat output processes including the thermal decomposition of electrolyte and electrodes,the reactions between electrolyte and electrodes,were analysed in this paper.The results show that the lithiated carbon reacted with electrolyte even at 40℃,and delithiated Li0.5CoO2 reacted with electrolyte at 132℃ with heat generation.In normal usage,the heat is mainly contri-buted by the impedance.When the temperature is over 72℃,exothermic reaction occurs inside the battery,with heat generation of 1 036.7 J/g.
In order to study the thermal behavior in lithium-ion battery,the main heat generation process in the battery was studied by means of a C80 calorimeter.The main heat output processes including the thermal decomposition of electrolyte and electrodes,the reactions between electrolyte and electrodes,were analysed in this paper.The results show that the lithiated carbon reacted with electrolyte even at 40℃,and delithiated Li0.5CoO2 reacted with electrolyte at 132℃ with heat generation.In normal usage,the heat is mainly contri-buted by the impedance.When the temperature is over 72℃,exothermic reaction occurs inside the battery,with heat generation of 1 036.7 J/g.
2006, 23(5): 494-497
Abstract:
Nickel oxide(NiO) thin films were fabricated by vacuum evaporation of Ni and subsequent thermal oxidation under oxygen atomsphere,the influences of oxidation temperature on the structures and electrochemical properties were explored.The results show that the prepared thin films are of nanocrystalline structure with the average particle size of 56~81 nm.With the increase of oxidation temperature,the specific capacity of NiO thin film increases but the cycling property deteriorates slightly.At the oxidation temperature of 600℃ for 2 h,NiO thin film prepared by vacuum evaporation and subsequent thermal oxidation possesses better rechargeable property and higher discharge capacity,and could be used as anode material in all-solid-state thin film Li-ion battery.
Nickel oxide(NiO) thin films were fabricated by vacuum evaporation of Ni and subsequent thermal oxidation under oxygen atomsphere,the influences of oxidation temperature on the structures and electrochemical properties were explored.The results show that the prepared thin films are of nanocrystalline structure with the average particle size of 56~81 nm.With the increase of oxidation temperature,the specific capacity of NiO thin film increases but the cycling property deteriorates slightly.At the oxidation temperature of 600℃ for 2 h,NiO thin film prepared by vacuum evaporation and subsequent thermal oxidation possesses better rechargeable property and higher discharge capacity,and could be used as anode material in all-solid-state thin film Li-ion battery.
2006, 23(5): 498-502
Abstract:
Poly(vinyl benzylchloride)(PVBC) latex nanoparticles were made by the emulsion polymerization.The influences of reaction temperature,surfactant concentration, initiator concentration and monomer concentration on the particle size were studied.The scanning electron microscope images and the particle size distribution analysis show that PVBC latex nanoparticles have an average of 95 nm when synthesized with the monomer,surfactant and initiator concentrations being 2.77%,0.042% and 0.025% at 50℃.
Poly(vinyl benzylchloride)(PVBC) latex nanoparticles were made by the emulsion polymerization.The influences of reaction temperature,surfactant concentration, initiator concentration and monomer concentration on the particle size were studied.The scanning electron microscope images and the particle size distribution analysis show that PVBC latex nanoparticles have an average of 95 nm when synthesized with the monomer,surfactant and initiator concentrations being 2.77%,0.042% and 0.025% at 50℃.
2006, 23(5): 503-507
Abstract:
Microstructure of cyhalothrin microemulsion was studied by means of conductivity measurement.When the mass ratio of surfactant,cyhalothrin-cyclohxanone solution and alcohol was fixed,the microstructure changed from W/O structure through bicontinuous structure to O/W structure as the alcohol was ethanol,and the there was a liquid crystal region before bicontinuous structure as the alcohol was n-octanol.The pseudo ternary phase diagrams of cyhalothrin microemulsion were presented.The mechanism of cyhalothrin microemulsion formation was studied,with the particular emphasis on the effects of different alcohols and different alcohol-contents on cyhalothrin microemulsion.It has been found that with the increase of carbon atom number of the alcohol,the area of microemulsion region increased first and decreased afterwards;and the area of microemulsion region decreased first and increased afterwards with the increase of alcohol-content.
Microstructure of cyhalothrin microemulsion was studied by means of conductivity measurement.When the mass ratio of surfactant,cyhalothrin-cyclohxanone solution and alcohol was fixed,the microstructure changed from W/O structure through bicontinuous structure to O/W structure as the alcohol was ethanol,and the there was a liquid crystal region before bicontinuous structure as the alcohol was n-octanol.The pseudo ternary phase diagrams of cyhalothrin microemulsion were presented.The mechanism of cyhalothrin microemulsion formation was studied,with the particular emphasis on the effects of different alcohols and different alcohol-contents on cyhalothrin microemulsion.It has been found that with the increase of carbon atom number of the alcohol,the area of microemulsion region increased first and decreased afterwards;and the area of microemulsion region decreased first and increased afterwards with the increase of alcohol-content.
2006, 23(5): 508-513
Abstract:
Meso-5,10,15,20-tetra(4-hydroxylphenyl) porphyrin(H2THPP) and meso-5,10,15,20-tetra(4-aminophenyl) porphyrin(H2THPP) were synthesized with the method described in the references.The metalloporphyrin complexes were prepared via the solid-state reactions of the porphyrins with Cu(Ac)2,Mn(Ac)2,Fe(Ac)2 or Co(Ac)2 and purified by using column chromatography,and the correspending nitrosyl metalloporphyrin complexes were synthesized by combining the metalloprphyrin complexes with nitric oxide.The structures of the above synthetic products were characterized by means of FT-IR,1H NMR,MS and elemental analysis.The NO-releasing properties of the nitrosyl metalloporphyrins in aqueous solutions were studied by diazotization at room temperature.The results show that NO-releasing efficiencies of THPP-CoNO,THPP-Fe-NO,TNPP-Co-NO and TNPP-Fe-NO were 59.48%,66.42%,63.17% and 62.04% respectively.
Meso-5,10,15,20-tetra(4-hydroxylphenyl) porphyrin(H2THPP) and meso-5,10,15,20-tetra(4-aminophenyl) porphyrin(H2THPP) were synthesized with the method described in the references.The metalloporphyrin complexes were prepared via the solid-state reactions of the porphyrins with Cu(Ac)2,Mn(Ac)2,Fe(Ac)2 or Co(Ac)2 and purified by using column chromatography,and the correspending nitrosyl metalloporphyrin complexes were synthesized by combining the metalloprphyrin complexes with nitric oxide.The structures of the above synthetic products were characterized by means of FT-IR,1H NMR,MS and elemental analysis.The NO-releasing properties of the nitrosyl metalloporphyrins in aqueous solutions were studied by diazotization at room temperature.The results show that NO-releasing efficiencies of THPP-CoNO,THPP-Fe-NO,TNPP-Co-NO and TNPP-Fe-NO were 59.48%,66.42%,63.17% and 62.04% respectively.
2006, 23(5): 514-518
Abstract:
Four solanesyl nitrogen mustards were designed and synthesized with solanesol or solanesyl amine as the carrier,maleic acid and phthalic acid as the linkers,and nitrogen mustard as the pharmacophore.Four similar nitrogen mustard derivatives were also prepared with the linear aliphatic alcohols instead of solanesyl derivatives as the carrier to compare their difference.The structures of the compounds were confirmed by IR,1H NMR,MS and elemental analysis.The in vitro anti-tumor activities of these compounds were tested preliminarily on KB,Bel-7402,HCT-8,A549 and MDA cells.The data show that the nitrogen mustard with solanesol as the carrier and maleic acid as the linker inhibits all the five tested cells.
Four solanesyl nitrogen mustards were designed and synthesized with solanesol or solanesyl amine as the carrier,maleic acid and phthalic acid as the linkers,and nitrogen mustard as the pharmacophore.Four similar nitrogen mustard derivatives were also prepared with the linear aliphatic alcohols instead of solanesyl derivatives as the carrier to compare their difference.The structures of the compounds were confirmed by IR,1H NMR,MS and elemental analysis.The in vitro anti-tumor activities of these compounds were tested preliminarily on KB,Bel-7402,HCT-8,A549 and MDA cells.The data show that the nitrogen mustard with solanesol as the carrier and maleic acid as the linker inhibits all the five tested cells.
2006, 23(5): 519-523
Abstract:
Penicillinase,hematein and nano gold colloid were immobilized,as a modified membrane,on a plane Pt electrode by glutaraldehyde-bovine serum albumin.The membrane-modified electrode was used to construct amperometric electrochemical biosensors for the determination of trace penicillin in milk.The principle is based on the use of pH-sensitive hematein as the redox-active probe molecule.At a suitable constant potential,when the local pH on the electrode surface or in its promixity changes as a consequence of the penicillin hydrolyzation,the current flow resulting from the electrochemical reaction of hematein also changes to an extent,which is correlated to the substrate concentration.To characterize the interactions of enzyme with nano Au colloid and hematein,electrochemical impedance spectroscopy(EIS) was used.The linear detection range of the modified Pt electrode is from 2.81×10-5 to 1.26×10-2 mmol/L in PBS and from 5.61×10-4 to 2.10×10-3 mmol/L in milk.The response time is 4 s.The electrode can be used for at least 15 days with the perfect reproducibility.The life of the electrode is 30 days.
Penicillinase,hematein and nano gold colloid were immobilized,as a modified membrane,on a plane Pt electrode by glutaraldehyde-bovine serum albumin.The membrane-modified electrode was used to construct amperometric electrochemical biosensors for the determination of trace penicillin in milk.The principle is based on the use of pH-sensitive hematein as the redox-active probe molecule.At a suitable constant potential,when the local pH on the electrode surface or in its promixity changes as a consequence of the penicillin hydrolyzation,the current flow resulting from the electrochemical reaction of hematein also changes to an extent,which is correlated to the substrate concentration.To characterize the interactions of enzyme with nano Au colloid and hematein,electrochemical impedance spectroscopy(EIS) was used.The linear detection range of the modified Pt electrode is from 2.81×10-5 to 1.26×10-2 mmol/L in PBS and from 5.61×10-4 to 2.10×10-3 mmol/L in milk.The response time is 4 s.The electrode can be used for at least 15 days with the perfect reproducibility.The life of the electrode is 30 days.
2006, 23(5): 524-527
Abstract:
The simultaneous determination of solanesol and coenzyme Q10 in the extract of tobacco(Nicotiana Tabacum L.) leaves by using reversed phase high performance liquid chromatography(RP-HPLC) method was established.The sample preparation process involved homogeneous extraction.The chromatogram was obtained on an HIQ SIL C18V column(4.6 mm×250 mm,5 μm) with V(acetonitrile):V(isopropanol)=8:7 as the mobile phase at a flow rate of 1.5 mL/min and 25℃.Diode array detection(DAD) was used and UV detection wave wavelength was set at 215 nm for solanesol and 275 nm for coenzyme Q10. The volume of injection sample was 20 μL.Under the chromatographic conditions,the recoveries of solanesol and coenzyme Q10 were(100.05±1.25)% and (99.97±1.36)% respectively.The method is simple,rapid,efficient and it is suitable to the determination of solanesol and coenzyme Q10 in the extract of tobacco leaves.
The simultaneous determination of solanesol and coenzyme Q10 in the extract of tobacco(Nicotiana Tabacum L.) leaves by using reversed phase high performance liquid chromatography(RP-HPLC) method was established.The sample preparation process involved homogeneous extraction.The chromatogram was obtained on an HIQ SIL C18V column(4.6 mm×250 mm,5 μm) with V(acetonitrile):V(isopropanol)=8:7 as the mobile phase at a flow rate of 1.5 mL/min and 25℃.Diode array detection(DAD) was used and UV detection wave wavelength was set at 215 nm for solanesol and 275 nm for coenzyme Q10. The volume of injection sample was 20 μL.Under the chromatographic conditions,the recoveries of solanesol and coenzyme Q10 were(100.05±1.25)% and (99.97±1.36)% respectively.The method is simple,rapid,efficient and it is suitable to the determination of solanesol and coenzyme Q10 in the extract of tobacco leaves.
2006, 23(5): 528-532
Abstract:
A novel nano-thickness carbon paste film electrode(INCPE) was constructed by inlaying carbon paste onto the surface of a nickel-chromium substrate.The surface structure of the INCPE was characterized by scanning electron microscopy(SEM), and the electrochemical behavior of the electrode was investigated by cyclic voltammetry,differential pulse voltammetry and multi-step semi-differential electrochemical method with vitamin B6 as the reactant.Vitamin B6 showed a very sensitive response at INCPE.In a phosphate buffer solution (pH=6.7), the oxidation peak current was proportional to the concentration of vitamin B6 in the range of 1.0×10-7~2.0×10-4 mol/L with a correlation coefficient of 0.995 2.The detection limit of vitamin B6 was 7.0×10-8 mol/L(N/S=3).These results confirm that INCPE is stable,sensitive,inexpensive,convenient,and could be used as a working electrode.
A novel nano-thickness carbon paste film electrode(INCPE) was constructed by inlaying carbon paste onto the surface of a nickel-chromium substrate.The surface structure of the INCPE was characterized by scanning electron microscopy(SEM), and the electrochemical behavior of the electrode was investigated by cyclic voltammetry,differential pulse voltammetry and multi-step semi-differential electrochemical method with vitamin B6 as the reactant.Vitamin B6 showed a very sensitive response at INCPE.In a phosphate buffer solution (pH=6.7), the oxidation peak current was proportional to the concentration of vitamin B6 in the range of 1.0×10-7~2.0×10-4 mol/L with a correlation coefficient of 0.995 2.The detection limit of vitamin B6 was 7.0×10-8 mol/L(N/S=3).These results confirm that INCPE is stable,sensitive,inexpensive,convenient,and could be used as a working electrode.
2006, 23(5): 533-537
Abstract:
SiW11Co/Polyaniline(PAn) was synthesized by co-insertion of HCl together with substituted heteropolyanion.Its thermal stability,fluorescence property,conductivity,cyclic voltammetric behavior and magnetism were investigated.The results revealed that SiW11Co/PAn had better thermal stability.Its decomposition temperature is about 162℃ higher than that of PAn base.The conductivity of the material is 0.54 S/cm.It has reversible electrochemical property.Its saturation magnetization is higher than that of the heteropolyacid,and at the same time,the system shows paramagnetism.
SiW11Co/Polyaniline(PAn) was synthesized by co-insertion of HCl together with substituted heteropolyanion.Its thermal stability,fluorescence property,conductivity,cyclic voltammetric behavior and magnetism were investigated.The results revealed that SiW11Co/PAn had better thermal stability.Its decomposition temperature is about 162℃ higher than that of PAn base.The conductivity of the material is 0.54 S/cm.It has reversible electrochemical property.Its saturation magnetization is higher than that of the heteropolyacid,and at the same time,the system shows paramagnetism.
2006, 23(5): 538-542
Abstract:
Novel 2-thiohydantoin derivatives were synthesized,and the structures of the title compounds were confirmed by 1H NMR,13C NMR,and IR.The preliminary biological tests of the title compounds were carried out.The structure-activity relationship was analyzed from structure characteristic and substituent effect.The results show that 5-methyl-2-thiohydantoin derivatives exhibit higher biological activity than those without 5-methyl.The maximum inhibiting rate is 56.5%(sprout) and 53.8%(root).2-Thiohydantoin derivatives can be made into novel pesticide precursor compounds.
Novel 2-thiohydantoin derivatives were synthesized,and the structures of the title compounds were confirmed by 1H NMR,13C NMR,and IR.The preliminary biological tests of the title compounds were carried out.The structure-activity relationship was analyzed from structure characteristic and substituent effect.The results show that 5-methyl-2-thiohydantoin derivatives exhibit higher biological activity than those without 5-methyl.The maximum inhibiting rate is 56.5%(sprout) and 53.8%(root).2-Thiohydantoin derivatives can be made into novel pesticide precursor compounds.
2006, 23(5): 543-547
Abstract:
The atom transfer radical suspension polymerization(ATRP) of methyl methacrylate(MMA) initiated by poly(vinyl chloride)(PVC) and catalyzed by iron dichloride tetrahydrate/triphenyl phosphine complexes was studied in different suspension systems at 80℃.The systems included ethanol,toluene/ethanol,toluene/H2O,H2O,H2O/Poly(vinyl alcohol)(PVA),and H2O/PVA/Dioctyl phthalate(DOP).A linear dependence of ln [M0]/[M] on reaction time was observed for only two suspension systems,toluene/ethanol and H2O/PVA/DOP,and a linear increase with reaction time of the number average molecular weight of copolymer PVC-g-PMMA was observed.The structures of the copolymers were characterized by IR, 1H NMR,GPC.The grafting efficiency of MMA were 6.7%,17.8%,26.0%,35.1%,respectively after polymerization of 6,15,21,27 h.
The atom transfer radical suspension polymerization(ATRP) of methyl methacrylate(MMA) initiated by poly(vinyl chloride)(PVC) and catalyzed by iron dichloride tetrahydrate/triphenyl phosphine complexes was studied in different suspension systems at 80℃.The systems included ethanol,toluene/ethanol,toluene/H2O,H2O,H2O/Poly(vinyl alcohol)(PVA),and H2O/PVA/Dioctyl phthalate(DOP).A linear dependence of ln [M0]/[M] on reaction time was observed for only two suspension systems,toluene/ethanol and H2O/PVA/DOP,and a linear increase with reaction time of the number average molecular weight of copolymer PVC-g-PMMA was observed.The structures of the copolymers were characterized by IR, 1H NMR,GPC.The grafting efficiency of MMA were 6.7%,17.8%,26.0%,35.1%,respectively after polymerization of 6,15,21,27 h.
2006, 23(5): 548-551
Abstract:
Alkylation of methylcarbomethoxycyclohexenone 1 with iodomethane in a basic solution gave dimethylcarbomethoxycyclohexenone 2,which was transfered to dimethylcarbomethoxycyclohexenol 3 through the selective reduction of keto-carbonyl with a total yield of ca.60%.The effects of hydrogen-grabbing agents and reducing agent on the two reactions were studied.The results show that:the optimum hydrogen-grabbing agent and reducing agent for the alkylation and selective reduction of keto-carbonyl are sodium hydride and lithium-aluminum tri-tetra-butoxy hydride,and the yields of the alkylation and the reduction product are 90% and 67%,respectively.Their structures were confirmed by means of elemental analysis,UV-Vis,1H NMR,IR,and MS spectra.
Alkylation of methylcarbomethoxycyclohexenone 1 with iodomethane in a basic solution gave dimethylcarbomethoxycyclohexenone 2,which was transfered to dimethylcarbomethoxycyclohexenol 3 through the selective reduction of keto-carbonyl with a total yield of ca.60%.The effects of hydrogen-grabbing agents and reducing agent on the two reactions were studied.The results show that:the optimum hydrogen-grabbing agent and reducing agent for the alkylation and selective reduction of keto-carbonyl are sodium hydride and lithium-aluminum tri-tetra-butoxy hydride,and the yields of the alkylation and the reduction product are 90% and 67%,respectively.Their structures were confirmed by means of elemental analysis,UV-Vis,1H NMR,IR,and MS spectra.
2006, 23(5): 552-556
Abstract:
The support vector machine(SVM),as a novel type of learning machine,was used to develop a QSPR model of Gibbs free energies of 607 organic compounds.The descriptors calculated by CODESSA were used to represent the molecular structures.Thirteen of those descriptors were selected by forward stepwise regression and were used developing models to predict Gibbs free energy of the formation of an organic compound.Multiple linear regression(MLR) and SVM were utilized to construct linear and non-linear models of the organic compound.The optimal QSPR model based on the support vector machine was obtained.The mean-absolute error(MAE) of Gibbs free energy of formation was 31.098 9 kJ/mol for the whole set, 30.569 5 kJ/mol for the training set,and 35.924 6 kJ/mol for the test set respectively.The prediction results are more satisfactory than those of MLR.
The support vector machine(SVM),as a novel type of learning machine,was used to develop a QSPR model of Gibbs free energies of 607 organic compounds.The descriptors calculated by CODESSA were used to represent the molecular structures.Thirteen of those descriptors were selected by forward stepwise regression and were used developing models to predict Gibbs free energy of the formation of an organic compound.Multiple linear regression(MLR) and SVM were utilized to construct linear and non-linear models of the organic compound.The optimal QSPR model based on the support vector machine was obtained.The mean-absolute error(MAE) of Gibbs free energy of formation was 31.098 9 kJ/mol for the whole set, 30.569 5 kJ/mol for the training set,and 35.924 6 kJ/mol for the test set respectively.The prediction results are more satisfactory than those of MLR.
2006, 23(5): 557-560
Abstract:
Crosslinked montmorillonite and the acid-treated crosslinked montmorillonite were studied by means of XRD,BET and SEM.For the 15%(mass fraction) acid-treated crosslinked montmorillonite,its surface area was 229 m2/g,d001=1.25 nm.Benzyl acetate was prepared directly from benzyl alcohol and acetic acid with acid-treated montmorillonite as the catalyst and toluene as the water stripping agent.The results show that the 15%(mass fraction) acid-treated crosslinked montmorillonite is an excellent catalyst.The optimum reaction conditions were that n(alcohol):n(acid) was 1:1.2,ω(cat)=0.4%,and the reaction time was 1.5 h.The esterification rate was about 99%.
Crosslinked montmorillonite and the acid-treated crosslinked montmorillonite were studied by means of XRD,BET and SEM.For the 15%(mass fraction) acid-treated crosslinked montmorillonite,its surface area was 229 m2/g,d001=1.25 nm.Benzyl acetate was prepared directly from benzyl alcohol and acetic acid with acid-treated montmorillonite as the catalyst and toluene as the water stripping agent.The results show that the 15%(mass fraction) acid-treated crosslinked montmorillonite is an excellent catalyst.The optimum reaction conditions were that n(alcohol):n(acid) was 1:1.2,ω(cat)=0.4%,and the reaction time was 1.5 h.The esterification rate was about 99%.
2006, 23(5): 561-565
Abstract:
Perovskite-type Composite Oxides of La0.7-xSrxNd0.3FeO3-δ(x=0.1,0.2,0.3) were synthesized by the auto combustion method with the metal nitrate as oxidizing reagent and glycine as reducing agent.The specific areas of the synthesized powders were measured by nitrogen adsorption method.The formation conditions,crystalline structure and microstructure of the samples were investigated with XRD,TG-DSC,TEM and SEM.The experimental results show that the single Perovskite-type phase was obtained after the powders calcined at 900℃ for 2 h.The electrical conductivities of the ceramics were determined by four-probe DC method in the temperature range of 450~800℃ in air.The specific area of the species decreases and the particle size increases with the increase of Sr content,and the crystal system transforms from orthorhombic to cubic gradually.The conduction mechanism is attributable to the adiabatic hopping of small polarons.The La0.5Sr0.2Nd0.3FeO3-δ sample sintered at 1 300℃ for 2 h shows the highest conductivity.
Perovskite-type Composite Oxides of La0.7-xSrxNd0.3FeO3-δ(x=0.1,0.2,0.3) were synthesized by the auto combustion method with the metal nitrate as oxidizing reagent and glycine as reducing agent.The specific areas of the synthesized powders were measured by nitrogen adsorption method.The formation conditions,crystalline structure and microstructure of the samples were investigated with XRD,TG-DSC,TEM and SEM.The experimental results show that the single Perovskite-type phase was obtained after the powders calcined at 900℃ for 2 h.The electrical conductivities of the ceramics were determined by four-probe DC method in the temperature range of 450~800℃ in air.The specific area of the species decreases and the particle size increases with the increase of Sr content,and the crystal system transforms from orthorhombic to cubic gradually.The conduction mechanism is attributable to the adiabatic hopping of small polarons.The La0.5Sr0.2Nd0.3FeO3-δ sample sintered at 1 300℃ for 2 h shows the highest conductivity.
2006, 23(5): 566-569
Abstract:
Ferulic Acid was studied via cyclic voltammetry and squre stripping voltammetry,the experimental parameters were optimized and a direct electroanalytical method for determining ferulic acid was developed.In the medium of HAc-NaAc(pH=5.6),a pair of sensitive peaks was observed in-1.0~1.2 V(vs.SCE).The oxidation peak current was proportional to the concentration of ferulic acid in the range of 5×10-5~1×10-3 mol/L and the detection limit was 1×10-6 mol/L.The method can be applied to the determination of trace ferulic acid in XiaoyaoWan without pretreatment.The recovery was 95%~106%.
Ferulic Acid was studied via cyclic voltammetry and squre stripping voltammetry,the experimental parameters were optimized and a direct electroanalytical method for determining ferulic acid was developed.In the medium of HAc-NaAc(pH=5.6),a pair of sensitive peaks was observed in-1.0~1.2 V(vs.SCE).The oxidation peak current was proportional to the concentration of ferulic acid in the range of 5×10-5~1×10-3 mol/L and the detection limit was 1×10-6 mol/L.The method can be applied to the determination of trace ferulic acid in XiaoyaoWan without pretreatment.The recovery was 95%~106%.
2006, 23(5): 570-572
Abstract:
The photoluminescence and electroluminescence properties of red Cu(Ⅰ) complex (BF4)(dbp=2,9-Di-tert-butyl-1,10-phenanthroline;dmp=2,9-Dimethyl-1,10-phenanthroline) were studied.The film of 20% Cu(Ⅰ) complex in PMMA exhibited a photoluminescence quantum yield of 5% with emission maximum at 617 nm.A short excited-state lifetime of 1.7 μs was also observed.Phosphorescent OLEDs with red emission identical to photoluminescence spectrum of the complex in PMMA film were fabricated by using poly vinyl carbazole(PVK) as host.A current efficiency of 0.9 cd/A along with a maximum brightness up to 631 cd/m2 was demonstrated.The triplet-triplet(T-T) annihilation under a high current density was not significant for these devices and might be attributed to the short excited-state lifetime of the complex.
The photoluminescence and electroluminescence properties of red Cu(Ⅰ) complex (BF4)(dbp=2,9-Di-tert-butyl-1,10-phenanthroline;dmp=2,9-Dimethyl-1,10-phenanthroline) were studied.The film of 20% Cu(Ⅰ) complex in PMMA exhibited a photoluminescence quantum yield of 5% with emission maximum at 617 nm.A short excited-state lifetime of 1.7 μs was also observed.Phosphorescent OLEDs with red emission identical to photoluminescence spectrum of the complex in PMMA film were fabricated by using poly vinyl carbazole(PVK) as host.A current efficiency of 0.9 cd/A along with a maximum brightness up to 631 cd/m2 was demonstrated.The triplet-triplet(T-T) annihilation under a high current density was not significant for these devices and might be attributed to the short excited-state lifetime of the complex.
2006, 23(5): 573-575
Abstract:
The interaction between N,N-dimethyldodecylamine N-oxide(DDAO) and salmon sperm DNA was studied.The Effect of pH on DDAO-DNA complex was investigated via the phase diagram.The hydrophobic interaction between non-ionic species DDAO and DNA was quite weak.At low DDAO concentrations,the cationic species of DDAO(protonated form) could not induce the conformational transformation of DNA either.As the concentration of DDAO was higher than the critical micelle concentration of non-ionic species,electrostatic attraction induced DDAO to combine with DNA strongly and phase separation at critical pH value.
The interaction between N,N-dimethyldodecylamine N-oxide(DDAO) and salmon sperm DNA was studied.The Effect of pH on DDAO-DNA complex was investigated via the phase diagram.The hydrophobic interaction between non-ionic species DDAO and DNA was quite weak.At low DDAO concentrations,the cationic species of DDAO(protonated form) could not induce the conformational transformation of DNA either.As the concentration of DDAO was higher than the critical micelle concentration of non-ionic species,electrostatic attraction induced DDAO to combine with DNA strongly and phase separation at critical pH value.
2006, 23(5): 576-578
Abstract:
Trilauryl phosphite ester was synthesized via the direct esterification reaction of lauryl alcohol and PCl3.When pyridine and benzene were used as the binding reagent of HCl and the solvent,respectively,from the orthogonal experiments,the suitable synthetic conditions were determined as follows:the reaction temperature was 60℃,the solvent quantity was 70 g,the dropwise time was 90 min,reaction time was 1.5 h,and the molar ratio of lauryl alcohol to PCl3 3.1:1.Under the above conditions,the yield was 95.9%.The quality of the product is as good as one of the overseas.
Trilauryl phosphite ester was synthesized via the direct esterification reaction of lauryl alcohol and PCl3.When pyridine and benzene were used as the binding reagent of HCl and the solvent,respectively,from the orthogonal experiments,the suitable synthetic conditions were determined as follows:the reaction temperature was 60℃,the solvent quantity was 70 g,the dropwise time was 90 min,reaction time was 1.5 h,and the molar ratio of lauryl alcohol to PCl3 3.1:1.Under the above conditions,the yield was 95.9%.The quality of the product is as good as one of the overseas.
2006, 23(5): 579-580
Abstract:
2-Nitro-4-chloro-2'-hydroxy-3'-t-butyl-5'-methyl-azobenzene was synthesized via diazo coupling reaction in solid phase with 4-chlor-2-nitroaniline,2-t-butyl-4-methyl phenol and sodium nitrite at room temperature.The reaction was completed through one-step method within 15 min in a yield of 93% with a higher than 99% purity(by HPLC),and the structure of the compound was comfirmed by IR and UV.
2-Nitro-4-chloro-2'-hydroxy-3'-t-butyl-5'-methyl-azobenzene was synthesized via diazo coupling reaction in solid phase with 4-chlor-2-nitroaniline,2-t-butyl-4-methyl phenol and sodium nitrite at room temperature.The reaction was completed through one-step method within 15 min in a yield of 93% with a higher than 99% purity(by HPLC),and the structure of the compound was comfirmed by IR and UV.
