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2010 Volume 27 Issue 9
2010, 27(9): 993-997
doi: 10.3724/SP.J.1095.2010.90735
Abstract:
Any marine structures such as ship hulls,jetties and platforms are subject to diverse and severe biofouling,which restricts their applications and results in a tremendous expense.Applying an antifouling coating on the surface has been widely used,nontoxic fouling release coatings have become the focus of current researches.This paper mainly reviews bioadhesion mechanism and surface engineering for antifouling coatings.Firstly,bioadhesion process and the forces of bioadhesion at interface were analyzed,then some main surface engineering techniques such as surface energy,elastic modulus,surface chemistry,topography,color and so on that influence antifouling effects were discussed,some problems existed in application were also addressed.
Any marine structures such as ship hulls,jetties and platforms are subject to diverse and severe biofouling,which restricts their applications and results in a tremendous expense.Applying an antifouling coating on the surface has been widely used,nontoxic fouling release coatings have become the focus of current researches.This paper mainly reviews bioadhesion mechanism and surface engineering for antifouling coatings.Firstly,bioadhesion process and the forces of bioadhesion at interface were analyzed,then some main surface engineering techniques such as surface energy,elastic modulus,surface chemistry,topography,color and so on that influence antifouling effects were discussed,some problems existed in application were also addressed.
2010, 27(9): 998-1003
doi: 10.3724/SP.J.1095.2010.90807
Abstract:
First-principle calculations have become a valuable tool in the study and exploration of new energy hydrogen storage materials.In this paper,novel results and important progresses on the first-principle calculations of hydrogen storage materials are introduced.The application of first-principle calculations in hydrogen storage materials can be summarized as follows:1) studying the hydrogen storage properties of nano-structures,2) clarifying the role of dopants and defects in the hydrogen storage materials,3) elucidating the hydrogen storage mechanisms,4) determining the structure of hydrogen storage materials and predicting new materials.The perspective of using first-principle calculations is proposed for future material innovation in the field of hydrogen storage.
First-principle calculations have become a valuable tool in the study and exploration of new energy hydrogen storage materials.In this paper,novel results and important progresses on the first-principle calculations of hydrogen storage materials are introduced.The application of first-principle calculations in hydrogen storage materials can be summarized as follows:1) studying the hydrogen storage properties of nano-structures,2) clarifying the role of dopants and defects in the hydrogen storage materials,3) elucidating the hydrogen storage mechanisms,4) determining the structure of hydrogen storage materials and predicting new materials.The perspective of using first-principle calculations is proposed for future material innovation in the field of hydrogen storage.
2010, 27(9): 1004-1007
doi: 10.3724/SP.J.1095.2010.90825
Abstract:
In order to solve the dewetting problem of nitramine propellants,polyether heterocycle amide bonding agent was prepared from glycerin,ethylene oxide,propylene oxide,propanetriol and isocyanuric.After incorporated into a glycidyl azide polymer(GAP)/cyclotetramethylene tetranitramine(HMX)/aluminum powder(Al)/ammonium perchlorate(AP) propellant,its mechanical properties were tested and its tensile fracture surface morphologies were investigated by SEM.The results show that the bonding agent can improve the maximum elongation ratio of the propellant at room,low and high temperatures effectively as well as the adhesion between oxidant and binder.But the tensile strength of the propellant need to be improved.
In order to solve the dewetting problem of nitramine propellants,polyether heterocycle amide bonding agent was prepared from glycerin,ethylene oxide,propylene oxide,propanetriol and isocyanuric.After incorporated into a glycidyl azide polymer(GAP)/cyclotetramethylene tetranitramine(HMX)/aluminum powder(Al)/ammonium perchlorate(AP) propellant,its mechanical properties were tested and its tensile fracture surface morphologies were investigated by SEM.The results show that the bonding agent can improve the maximum elongation ratio of the propellant at room,low and high temperatures effectively as well as the adhesion between oxidant and binder.But the tensile strength of the propellant need to be improved.
2010, 27(9): 1008-1011
doi: 10.3724/SP.J.1095.2010.90713
Abstract:
4,4'-Dibromo-6,6'-bis (N,N-bis (ethoxycarbonylmethyl) amino methyl)-2,2'-bipyridine was prepared from 4,4'-dinitro-6,6'-dimethyl-2,2'-bipyridine N,N-dioxide by esterification with trifluoroacetic anhydride and hydroxymethylation,bromine methylation with HBr,and methylation of amino hydrogen with diethyl iminodiacetate.The structure of this product was determined by DSC,IR,1H NMR,HPLC and HRMS.The obtained product is an important intermediate for the synthesis of a bi-functional chelate,which could find applications in solid phase time resolved fluoroimmunoassay.
4,4'-Dibromo-6,6'-bis (N,N-bis (ethoxycarbonylmethyl) amino methyl)-2,2'-bipyridine was prepared from 4,4'-dinitro-6,6'-dimethyl-2,2'-bipyridine N,N-dioxide by esterification with trifluoroacetic anhydride and hydroxymethylation,bromine methylation with HBr,and methylation of amino hydrogen with diethyl iminodiacetate.The structure of this product was determined by DSC,IR,1H NMR,HPLC and HRMS.The obtained product is an important intermediate for the synthesis of a bi-functional chelate,which could find applications in solid phase time resolved fluoroimmunoassay.
2010, 27(9): 1012-1016
doi: 10.3724/SP.J.1095.2010.90765
Abstract:
A series of 5-chloro-o-hydroxyphenyl amino acid esters schiff bases was designed and synthesized by the condensation of chlorinated salicylaldehyde with amino acid esters including phenylalamine methyl (ethyl) ester,leucine methyl(ethyl) ester and glycinate methyl(ethyl) ester,which were subjected to further reduction form 5-chloro-o-hydroxybenzyl amino acid esters.The structures of these compounds were characterized by IR,1H NMR and elemental analysis.The antibacterial activity assay indicates that these compounds resist different bacteria to different degrees.The result of preliminary bioassay shows that at a mass concentration of 0.01%,the inhibitory rate of the 5-chloro-o-hydroxyphenyl amino acid esters schiff base against Escherichia coli is over 90% and the inhibitory rate of the 5-chloro-o-hydroxybenzyl amino acid esters against Staphylococcus aureus is also over 90%.In addition,the inhibitory rate of 5-chloro-o-hydroxybenzyl phenylalamine ester against Staphylococcus aureus can be as high as 98%.
A series of 5-chloro-o-hydroxyphenyl amino acid esters schiff bases was designed and synthesized by the condensation of chlorinated salicylaldehyde with amino acid esters including phenylalamine methyl (ethyl) ester,leucine methyl(ethyl) ester and glycinate methyl(ethyl) ester,which were subjected to further reduction form 5-chloro-o-hydroxybenzyl amino acid esters.The structures of these compounds were characterized by IR,1H NMR and elemental analysis.The antibacterial activity assay indicates that these compounds resist different bacteria to different degrees.The result of preliminary bioassay shows that at a mass concentration of 0.01%,the inhibitory rate of the 5-chloro-o-hydroxyphenyl amino acid esters schiff base against Escherichia coli is over 90% and the inhibitory rate of the 5-chloro-o-hydroxybenzyl amino acid esters against Staphylococcus aureus is also over 90%.In addition,the inhibitory rate of 5-chloro-o-hydroxybenzyl phenylalamine ester against Staphylococcus aureus can be as high as 98%.
2010, 27(9): 1017-1020
doi: 10.3724/SP.J.1095.2010.90838
Abstract:
Using DMF as solvent,3,3'-diaminobenzidine and aromatic aldehydes as starting materials,and KI as catalyst,six new bisbenzimidazoles were synthesized in the presence of air.The structures of the compounds were characterized by means of FTIR,1H NMR,13C NMR,MS and elemental analysis.The optimal synthetic conditions were investigated.When the temperature was 150℃ and the reaction time was 12 h,the six compounds were obtained with yields in the range of 58.4% to 98.0%.The new method with readily available catalyst is advantageous to conventional synthetic process of bisbenzimidazoles due to its less steps,simpler operations,easier post-processings and higher yields.The anti-tumor activities of the target compounds were preliminarily examined via MTT method on Bel-7402 cell in vitro,and they exhibited certain inhibition activities.
Using DMF as solvent,3,3'-diaminobenzidine and aromatic aldehydes as starting materials,and KI as catalyst,six new bisbenzimidazoles were synthesized in the presence of air.The structures of the compounds were characterized by means of FTIR,1H NMR,13C NMR,MS and elemental analysis.The optimal synthetic conditions were investigated.When the temperature was 150℃ and the reaction time was 12 h,the six compounds were obtained with yields in the range of 58.4% to 98.0%.The new method with readily available catalyst is advantageous to conventional synthetic process of bisbenzimidazoles due to its less steps,simpler operations,easier post-processings and higher yields.The anti-tumor activities of the target compounds were preliminarily examined via MTT method on Bel-7402 cell in vitro,and they exhibited certain inhibition activities.
2010, 27(9): 1021-1025
doi: 10.3724/SP.J.1095.2010.90803
Abstract:
Preparation of dicyclopentadiene dioxide (DCPDDO) by the epoxidation of dicyclopentadiene (DCPD) with 50% industrial hydrogen peroxide as oxidant and the macroporous crosslinked polystyrene resin(PS) grafted N-benzyl-N,N-dimethyl-N-dodecyl quaternary ammonium phosphor tungsten heterpoly acid salts as tri-phase phase transfer catalyst was reported.The product was characterized by FTIR and 1H NMR.Effects of the volume of solvent,the amount of catalyst,the molar ratio of reactants,reaction temperature and reaction time on the reaction were studied.The optimal reaction conditions obtained by means of orthogonal test were (based on 0.05 mol DCPD):dichloroethane 18 mL,catalyst 2.25 g,n(DCPD):n(H2O2)=1:2.75, reaction temperature 60℃,reaction time 12 h.Under these conditions,the yield of DCPDDO can reach 89%.The catalyst can be easily recycled and no significant decrease in terms of catalytic activity could be observed after seven recycles.
Preparation of dicyclopentadiene dioxide (DCPDDO) by the epoxidation of dicyclopentadiene (DCPD) with 50% industrial hydrogen peroxide as oxidant and the macroporous crosslinked polystyrene resin(PS) grafted N-benzyl-N,N-dimethyl-N-dodecyl quaternary ammonium phosphor tungsten heterpoly acid salts as tri-phase phase transfer catalyst was reported.The product was characterized by FTIR and 1H NMR.Effects of the volume of solvent,the amount of catalyst,the molar ratio of reactants,reaction temperature and reaction time on the reaction were studied.The optimal reaction conditions obtained by means of orthogonal test were (based on 0.05 mol DCPD):dichloroethane 18 mL,catalyst 2.25 g,n(DCPD):n(H2O2)=1:2.75, reaction temperature 60℃,reaction time 12 h.Under these conditions,the yield of DCPDDO can reach 89%.The catalyst can be easily recycled and no significant decrease in terms of catalytic activity could be observed after seven recycles.
2010, 27(9): 1026-1031
doi: 10.3724/SP.J.1095.2010.90506
Abstract:
Thirteen new β-amino ketones were designed and synthesized directly through the Mannich reaction of sulfamethoxazole,4-hydroxyacetophenone and aromatic aldehydes in good yields.The reaction selectively occurred at the α-position of the carbonyl group of 4-hydroxyacetophenone. Their chemical structures were confirmed by means of 1H NMR,13C NMR and MS.Biological activity tests showed that in the rage of low concentrations,these title compounds displayed a certain inhibitory activity against protein tyrosine phosphatase 1B (PTP1B) and α-glucosidase.Moreover,some could activate the peroxisome proliferator-activated receptor response element(PPRE) moderately.The PPRE agonist activity of eight compounds was over 40%,among them compound 11 showed the highest activity(72.7%),which deserved further study.
Thirteen new β-amino ketones were designed and synthesized directly through the Mannich reaction of sulfamethoxazole,4-hydroxyacetophenone and aromatic aldehydes in good yields.The reaction selectively occurred at the α-position of the carbonyl group of 4-hydroxyacetophenone. Their chemical structures were confirmed by means of 1H NMR,13C NMR and MS.Biological activity tests showed that in the rage of low concentrations,these title compounds displayed a certain inhibitory activity against protein tyrosine phosphatase 1B (PTP1B) and α-glucosidase.Moreover,some could activate the peroxisome proliferator-activated receptor response element(PPRE) moderately.The PPRE agonist activity of eight compounds was over 40%,among them compound 11 showed the highest activity(72.7%),which deserved further study.
2010, 27(9): 1032-1037
doi: 10.3724/SP.J.1095.2010.90729
Abstract:
2,6-Di(2'-imidazoline-2'-yl) pyridine(L) was synthesized from pyridine 2,6-dicarboxylic acid and ethylenediamine under microwave irradiation without catalyst.Its chromium complex[CrL2] [NO3]3 was synthesized by the conventional method.The complex was characterized by IR spectrometry,elemental analysis,1H NMR,TG-DSC and molar conductivity.The bindings of these two compounds to DNA were investigated by UV spectrometry and viscosity measurement.It is believed that the ligand may bind to DNA by hydrogen bonding and groove-face binding and the complex bind to DNA by hydrogen bonding and external electrostatic binding.The calculation results from density functional theory (DFT) with hybrid functional B3LYP is good agreement with the experimental phenomena.
2,6-Di(2'-imidazoline-2'-yl) pyridine(L) was synthesized from pyridine 2,6-dicarboxylic acid and ethylenediamine under microwave irradiation without catalyst.Its chromium complex[CrL2] [NO3]3 was synthesized by the conventional method.The complex was characterized by IR spectrometry,elemental analysis,1H NMR,TG-DSC and molar conductivity.The bindings of these two compounds to DNA were investigated by UV spectrometry and viscosity measurement.It is believed that the ligand may bind to DNA by hydrogen bonding and groove-face binding and the complex bind to DNA by hydrogen bonding and external electrostatic binding.The calculation results from density functional theory (DFT) with hybrid functional B3LYP is good agreement with the experimental phenomena.
2010, 27(9): 1038-1041
doi: 10.3724/SP.J.1095.2010.90715
Abstract:
Using baicalin,the main active component of a traditional Chinese herb Scutellaria baicalensis, and one of its derivative,6,7-diacetoxylbaicalein,as precursors,a series of C8-substituted and di or tri-O-methylated baicalein derivatives was synthesized in good yields by iodination,nitration,reductive amination and selective methoxylation or hydrolysis of 6,7-diacetoxylbaicalein.The structures of these producrs were characterized.They featured with a broad spectrum of biological activities,notably anti-oxidant.
Using baicalin,the main active component of a traditional Chinese herb Scutellaria baicalensis, and one of its derivative,6,7-diacetoxylbaicalein,as precursors,a series of C8-substituted and di or tri-O-methylated baicalein derivatives was synthesized in good yields by iodination,nitration,reductive amination and selective methoxylation or hydrolysis of 6,7-diacetoxylbaicalein.The structures of these producrs were characterized.They featured with a broad spectrum of biological activities,notably anti-oxidant.
2010, 27(9): 1042-1045
doi: 10.3724/SP.J.1095.2010.90693
Abstract:
A hydrophilic resin with 4-aminopyridine was synthesized by the amination of macroporous glycidyl methacrylate-divinylbenzene copolymer(PGMA) beads with 4-aminopyridine.Its static adsorption performance and influence factors toward Hg(Ⅱ),Pb(Ⅱ),Cu(Ⅱ),Zn(Ⅱ) were investigated. At 25℃,the static adsorption capacities for Hg(Ⅱ),Pb(Ⅱ),Cu(Ⅱ),Zn(Ⅱ) are 2.145,1.715,1.023 and 0.654 mmol/g, respectively. The optimal pH value for the adsorption is in the range of 4.5~5.0.In addition,the adsorptive properties for the heavy metal ions could be improved with the increase of temperatures. The adsorption isotherms approximately fit the Langmuir and Freundlich equations within the range of experimental concentrations.
A hydrophilic resin with 4-aminopyridine was synthesized by the amination of macroporous glycidyl methacrylate-divinylbenzene copolymer(PGMA) beads with 4-aminopyridine.Its static adsorption performance and influence factors toward Hg(Ⅱ),Pb(Ⅱ),Cu(Ⅱ),Zn(Ⅱ) were investigated. At 25℃,the static adsorption capacities for Hg(Ⅱ),Pb(Ⅱ),Cu(Ⅱ),Zn(Ⅱ) are 2.145,1.715,1.023 and 0.654 mmol/g, respectively. The optimal pH value for the adsorption is in the range of 4.5~5.0.In addition,the adsorptive properties for the heavy metal ions could be improved with the increase of temperatures. The adsorption isotherms approximately fit the Langmuir and Freundlich equations within the range of experimental concentrations.
2010, 27(9): 1046-1049
doi: 10.3724/SP.J.1095.2010.90749
Abstract:
Regular porous films were prepared using polystyrene,dodecylacrylamide and ω-carboxyhexylacryl-amide(CAP) and chloroform as raw materials by a solvent evaporation self-organization.After separating the upper from lower surfaces under an applied force,pin-cushion array films with a micro-level superhydrophobicity could be obtained.The as obtained superhydrophobic film has a contact angle up to 158 °.
Regular porous films were prepared using polystyrene,dodecylacrylamide and ω-carboxyhexylacryl-amide(CAP) and chloroform as raw materials by a solvent evaporation self-organization.After separating the upper from lower surfaces under an applied force,pin-cushion array films with a micro-level superhydrophobicity could be obtained.The as obtained superhydrophobic film has a contact angle up to 158 °.
2010, 27(9): 1050-1054
doi: 10.3724/SP.J.1095.2010.90767
Abstract:
4-Styrene sulphonate intercalated layered double hydroxide (LDH) (MgAl-SS LDH),10-undecylenate intercalated LDH(MgAl-U LDH),polyoxyethylene(10) α-propenyl alkylphenyl ether sulfate (HS-10) intercalated LDH(MgAl-HS10 LDH) were prepared by co-precipitation methods,respectively. The structure of LDH was characterized by X-ray diffraction,fourier transform infrared spectrometry,element analysis,and energy spectrum analysis. Three kinds of LDH were dispersed in different solvents. The particle size and morphology of LDH dispersions were investigated by laser particle analyzer and transmission electron microscope. It was found that MgAl-HS10 LDH could be well dispersed and partially exfoliate in dimethyl sulfoxide.Hansen's three-dimensional solubility parameters were adopted to explain the dispersion activity of LDH. LDH dispersions were stable when the Hansen's dimensional solubility parameters of the hydrophobic groups of intercalated agents are similar to those of the solvents. LDH layer has a strong exfoliation tendency when both polar(δp) and hydrogen-bonding(δh) forces of the hydrophobic groups of the intercalated agents are comparable to those of the solvents.
4-Styrene sulphonate intercalated layered double hydroxide (LDH) (MgAl-SS LDH),10-undecylenate intercalated LDH(MgAl-U LDH),polyoxyethylene(10) α-propenyl alkylphenyl ether sulfate (HS-10) intercalated LDH(MgAl-HS10 LDH) were prepared by co-precipitation methods,respectively. The structure of LDH was characterized by X-ray diffraction,fourier transform infrared spectrometry,element analysis,and energy spectrum analysis. Three kinds of LDH were dispersed in different solvents. The particle size and morphology of LDH dispersions were investigated by laser particle analyzer and transmission electron microscope. It was found that MgAl-HS10 LDH could be well dispersed and partially exfoliate in dimethyl sulfoxide.Hansen's three-dimensional solubility parameters were adopted to explain the dispersion activity of LDH. LDH dispersions were stable when the Hansen's dimensional solubility parameters of the hydrophobic groups of intercalated agents are similar to those of the solvents. LDH layer has a strong exfoliation tendency when both polar(δp) and hydrogen-bonding(δh) forces of the hydrophobic groups of the intercalated agents are comparable to those of the solvents.
2010, 27(9): 1055-1060
doi: 10.3724/SP.J.1095.2010.90651
Abstract:
Four one-dimensional(1D) Ln(Ⅲ) coordination polymers[Eu2(C9H7O2)6(C9H7O2H)(C2H5OH)]n(1)、[Sm(C9H7O2)3]n(2)、[Tb(C9H7O2)3]n(3) and[Gd(C9H7O2)3]n(4)(C9H8O2=cinnamate acid) were synthesized by hydrothermal method,and their structures were determined by single-crystal X-ray diffraction.The Ln(Ⅲ) ions were nine-coordinated in these four complexes,and the bridging ligands were all cinnamate groups.However,the coordination environments of the central Ln(Ⅲ) ions were appreciably different.The complexes were characterized by IR,UV-Vis-NIR and fluorescence spectroscopy.The study on luminescent property in the visible region reveals that complex 1 emits red light,complexes 2 and 3 emit green light,but complex 4 emits feeblish blue light.In addition,the influence of the cinnamic ligand with softness and rigidity on the construction of coordination polymers and the luminescence of Ln(Ⅲ) ions was discussed.
Four one-dimensional(1D) Ln(Ⅲ) coordination polymers[Eu2(C9H7O2)6(C9H7O2H)(C2H5OH)]n(1)、[Sm(C9H7O2)3]n(2)、[Tb(C9H7O2)3]n(3) and[Gd(C9H7O2)3]n(4)(C9H8O2=cinnamate acid) were synthesized by hydrothermal method,and their structures were determined by single-crystal X-ray diffraction.The Ln(Ⅲ) ions were nine-coordinated in these four complexes,and the bridging ligands were all cinnamate groups.However,the coordination environments of the central Ln(Ⅲ) ions were appreciably different.The complexes were characterized by IR,UV-Vis-NIR and fluorescence spectroscopy.The study on luminescent property in the visible region reveals that complex 1 emits red light,complexes 2 and 3 emit green light,but complex 4 emits feeblish blue light.In addition,the influence of the cinnamic ligand with softness and rigidity on the construction of coordination polymers and the luminescence of Ln(Ⅲ) ions was discussed.
2010, 27(9): 1061-1064
doi: 10.3724/SP.J.1095.2010.90853
Abstract:
The bindings of small molecular oxazine 750 to d[TG4T]4,d[G4T4G4]2 and c-myc sequences was characterized by means of circular dichroism,thermal denaturation,and so on. Oxazine 750 was found to bind preferentially and strongly to parallel G-quadruplex. It can effectively stabilize the parallel G-quadruplex and destabilize the antiparallel G-quadruplex. The melting temperature of d[TG4T]4 or c-myc is increased by about 11℃ or 40℃ by oxazine 750,respectively. Under the same condition,oxazine 750 decreased the melting temperature of d[G4T4G4]2 by about 8℃.
The bindings of small molecular oxazine 750 to d[TG4T]4,d[G4T4G4]2 and c-myc sequences was characterized by means of circular dichroism,thermal denaturation,and so on. Oxazine 750 was found to bind preferentially and strongly to parallel G-quadruplex. It can effectively stabilize the parallel G-quadruplex and destabilize the antiparallel G-quadruplex. The melting temperature of d[TG4T]4 or c-myc is increased by about 11℃ or 40℃ by oxazine 750,respectively. Under the same condition,oxazine 750 decreased the melting temperature of d[G4T4G4]2 by about 8℃.
2010, 27(9): 1065-1070
doi: 10.3724/SP.J.1095.2010.90771
Abstract:
A new approach to directly electrodeposit platinum nanoparticles onto the mesoporous carbon CMK-3 via cyclic potential scanning technique was used to obtain Pt/CMK-3(Ⅰ) electrode. TEM images show that Pt nanoparticles with an average particle size of about 5 nm have been attached on the outer surface of the CMK-3. The electrocatalytic activity of Pt/CMK-3 for methanol oxidation was studied. When the platinum loading was 20% in the catalysts,the H2PtCl6 exhibited the maximum efficiency; current density was 382 A/g in 1 mol/L CH3OH+0.5 mol/L H2SO4 solution. The Pt/CMK-3 catalyst presented here possessed higher electrocatalytic activity than Pt/XC-72 and Pt/CMK-3 prepared by conventional electrodepositing method.
A new approach to directly electrodeposit platinum nanoparticles onto the mesoporous carbon CMK-3 via cyclic potential scanning technique was used to obtain Pt/CMK-3(Ⅰ) electrode. TEM images show that Pt nanoparticles with an average particle size of about 5 nm have been attached on the outer surface of the CMK-3. The electrocatalytic activity of Pt/CMK-3 for methanol oxidation was studied. When the platinum loading was 20% in the catalysts,the H2PtCl6 exhibited the maximum efficiency; current density was 382 A/g in 1 mol/L CH3OH+0.5 mol/L H2SO4 solution. The Pt/CMK-3 catalyst presented here possessed higher electrocatalytic activity than Pt/XC-72 and Pt/CMK-3 prepared by conventional electrodepositing method.
2010, 27(9): 1071-1075
doi: 10.3724/SP.J.1095.2010.90778
Abstract:
Growth behavior and desulfurization ratio of Rhodococcus Erythropolis NCC-1 with the presence of direct currents(DC) were studied.The electric field-activated mechanism was also investigated.The results show that direct current can improve the desulfurization ratio of NCC-1 within an appropriate scope of current density.The optimized current density is 0.72 A/m2.Using 0.2 mmol/L dibenzothiophene (DBT) as a probe,the complete removal time of DBT by NCC-1 could be shortened on platinum electrodes,e.g.24 h less than that without the presence of direct electric fieldor 48 h less than that using titanium electrodes under a current density of 0.72 A/m2.The desulfurization ratio can reach 67.4% at platinum electrodes under optimized direct current density in a mixture of water to diesel fuel with a ratio of 1:9.This value is 11.7% and 24.6% higher than those achieved on titanium electrode and in a system without the presence of direct electric field,respectively.This could be ascribed to the different ratio of adsorbed hydrogen to released H2 produced from water on the cathode.The released H2 could significantly promote the shaking culture of the bacterium.
Growth behavior and desulfurization ratio of Rhodococcus Erythropolis NCC-1 with the presence of direct currents(DC) were studied.The electric field-activated mechanism was also investigated.The results show that direct current can improve the desulfurization ratio of NCC-1 within an appropriate scope of current density.The optimized current density is 0.72 A/m2.Using 0.2 mmol/L dibenzothiophene (DBT) as a probe,the complete removal time of DBT by NCC-1 could be shortened on platinum electrodes,e.g.24 h less than that without the presence of direct electric fieldor 48 h less than that using titanium electrodes under a current density of 0.72 A/m2.The desulfurization ratio can reach 67.4% at platinum electrodes under optimized direct current density in a mixture of water to diesel fuel with a ratio of 1:9.This value is 11.7% and 24.6% higher than those achieved on titanium electrode and in a system without the presence of direct electric field,respectively.This could be ascribed to the different ratio of adsorbed hydrogen to released H2 produced from water on the cathode.The released H2 could significantly promote the shaking culture of the bacterium.
2010, 27(9): 1076-1082
doi: 10.3724/SP.J.1095.2010.90742
Abstract:
Laccase was immobilized on N,N'-methylene bis(acrylamide) (BIS) cross-linked poly(methyl acrylic acid) through covalent coupling strategy.The ratio of immobilization was determined and the specific activity of entrapped laccase was measured.Thermal stability,reusability of immobilized laccase and enzymatic parameters for 2,6-dimethoxyphenol (DMP) oxidation catalyzed by immobilized laccase were investigated.Results obtained from experiments indicate that the loading of laccase on this cross-linked copolymer matrix and the specific activity of immobilized laccase can reach up to 26.37 mg/g and 1.202 U/mg respectively.Laccase immobilization on this cross-linked copolymer matrix at 50℃ for 2 h can still retain about 83% of its initial activity and can retain more than 80% of its initial activity after 10 repeated uses.The apparent velocity constant kcat for DMP oxidation catalyzed by the entrapped enzyme can reach ca.1090 min-1.The reduction of oxygen at laccase-entrapped BIS cross-linked poly (methyl acrylic acid) modified glassy carbon electrode in phosphate buffer solution(pH=4.4) occurred near +724 mV(vs.SCE).
Laccase was immobilized on N,N'-methylene bis(acrylamide) (BIS) cross-linked poly(methyl acrylic acid) through covalent coupling strategy.The ratio of immobilization was determined and the specific activity of entrapped laccase was measured.Thermal stability,reusability of immobilized laccase and enzymatic parameters for 2,6-dimethoxyphenol (DMP) oxidation catalyzed by immobilized laccase were investigated.Results obtained from experiments indicate that the loading of laccase on this cross-linked copolymer matrix and the specific activity of immobilized laccase can reach up to 26.37 mg/g and 1.202 U/mg respectively.Laccase immobilization on this cross-linked copolymer matrix at 50℃ for 2 h can still retain about 83% of its initial activity and can retain more than 80% of its initial activity after 10 repeated uses.The apparent velocity constant kcat for DMP oxidation catalyzed by the entrapped enzyme can reach ca.1090 min-1.The reduction of oxygen at laccase-entrapped BIS cross-linked poly (methyl acrylic acid) modified glassy carbon electrode in phosphate buffer solution(pH=4.4) occurred near +724 mV(vs.SCE).
2010, 27(9): 1083-1087
doi: 10.3724/SP.J.1095.2010.90781
Abstract:
The liquid membrane oscillation between two immiscible phases can be applied to simulate the electron transfer process in biomembrane,therefore the molecular recognition based on unique potential oscillation can be applied to chemical analysis.In this work,a liquid membrane oscillation system of water cetyltrimethyl ammonium bromide (CTAB)/n-propanol)/oil (nitromethane solution of picric acid)/water (glucose solution) was established.The influence of alkyl homologues on the liquid membrane oscillation system was studied with the presence of n-hexane,n-octane,n-decane,n-dodecane,n-tetradecane,n-hexadecane,cyclohexane or iso-octane,etc.The results indicate that the amplitude and frequency of the liquid membrane oscillation curve are closely related to the added alkanes.Therefore,it is possible to differentiate alkanes using the liquid membrane oscillation system.
The liquid membrane oscillation between two immiscible phases can be applied to simulate the electron transfer process in biomembrane,therefore the molecular recognition based on unique potential oscillation can be applied to chemical analysis.In this work,a liquid membrane oscillation system of water cetyltrimethyl ammonium bromide (CTAB)/n-propanol)/oil (nitromethane solution of picric acid)/water (glucose solution) was established.The influence of alkyl homologues on the liquid membrane oscillation system was studied with the presence of n-hexane,n-octane,n-decane,n-dodecane,n-tetradecane,n-hexadecane,cyclohexane or iso-octane,etc.The results indicate that the amplitude and frequency of the liquid membrane oscillation curve are closely related to the added alkanes.Therefore,it is possible to differentiate alkanes using the liquid membrane oscillation system.
2010, 27(9): 1093-1098
doi: 10.3724/SP.J.1095.2010.90751
Abstract:
A hemoglobin/poly (L-glutamic acid)/glassy carbon electrode (Hb/PGA/GCE),targeted for reversible oxidation of p-phenylenediamine(PPD),has been fabricated by covalently immobilizing Hb on GCE with a thin layer of conductive pre-electropolymerized PGA.Electrochemical impedance spectra of the electrode confirmed the immobilization of Hb.The resulting modified electrode(Hb/PGA/GCE) gave a redox couple for Hb in PBS buffer and a better electrocatalytic performance to H2O2.This indicated that the direct electron transfer of the active group of the protein could be retained on the electrode surface.The oxidation of PPD was reversible on Hb/PGA/GCE instead of GCE or PGA/GCE.The redox peak current was proportional to the scan rate,and Ip,a/Ip,c about 1.02,indicating a characteristic of quasi-reversible,surface confined electrochemical behavior.Moreover,a new measurement method for PPD in samples was provided since the redox peak currents increased linearly with the concentration of PPD,Ip,a (μA)=3.124+0.705 cPPD (mmol/L) (r=0.9973).The enzymatic oxidation might be the plausible mechanism because the existence of H2O2 was in favor of the reversible redox of PPD.
A hemoglobin/poly (L-glutamic acid)/glassy carbon electrode (Hb/PGA/GCE),targeted for reversible oxidation of p-phenylenediamine(PPD),has been fabricated by covalently immobilizing Hb on GCE with a thin layer of conductive pre-electropolymerized PGA.Electrochemical impedance spectra of the electrode confirmed the immobilization of Hb.The resulting modified electrode(Hb/PGA/GCE) gave a redox couple for Hb in PBS buffer and a better electrocatalytic performance to H2O2.This indicated that the direct electron transfer of the active group of the protein could be retained on the electrode surface.The oxidation of PPD was reversible on Hb/PGA/GCE instead of GCE or PGA/GCE.The redox peak current was proportional to the scan rate,and Ip,a/Ip,c about 1.02,indicating a characteristic of quasi-reversible,surface confined electrochemical behavior.Moreover,a new measurement method for PPD in samples was provided since the redox peak currents increased linearly with the concentration of PPD,Ip,a (μA)=3.124+0.705 cPPD (mmol/L) (r=0.9973).The enzymatic oxidation might be the plausible mechanism because the existence of H2O2 was in favor of the reversible redox of PPD.
2010, 27(9): 1099-1104
doi: 10.3724/SP.J.1095.2010.90852
Abstract:
Bottom Up analysis strategy,combined with HPLC and nano-spray Fourier transfrom ion cyclotron resonance mass spectrometry(FT-ICR-MS) technology,was applied to the fragmentation of different proteins separated and purified from human milk.With the high sensitivity and dynamic range of FT-ICR-MS, the detection of different peptide fragmentations in proteins at lowlevels could be fulfilled.Taking advantage of the protein database in the Mascot search engine,the compositions of the major proteins in the fat,whey and pellet parts can be determined efficiently on the basis of complementary relationship of fragmented polypeptides by collisional activated dissociation(CAD) and electron capture dissociation(ECD) techniques.The result shows that keratin,albumin(ALB) protein and lactotransferrin were contained in all the three parts but with different types and quantities,suggesting the nutrition difference among these three parts in human milk.
Bottom Up analysis strategy,combined with HPLC and nano-spray Fourier transfrom ion cyclotron resonance mass spectrometry(FT-ICR-MS) technology,was applied to the fragmentation of different proteins separated and purified from human milk.With the high sensitivity and dynamic range of FT-ICR-MS, the detection of different peptide fragmentations in proteins at lowlevels could be fulfilled.Taking advantage of the protein database in the Mascot search engine,the compositions of the major proteins in the fat,whey and pellet parts can be determined efficiently on the basis of complementary relationship of fragmented polypeptides by collisional activated dissociation(CAD) and electron capture dissociation(ECD) techniques.The result shows that keratin,albumin(ALB) protein and lactotransferrin were contained in all the three parts but with different types and quantities,suggesting the nutrition difference among these three parts in human milk.
2010, 27(9): 1105-1107
doi: 10.3724/SP.J.1095.2010.90797
Abstract:
Key intermediate pyridinyl-1H-pyrazole-5-carboxylic acid was synthesized from the reaction of 2,3-dichloropyridine with hydrazine,which was then treated with diethyl maleate,then esterified through halogenation,oxidation,hydrolysis.Carbonyl chloride was synthesized by dichloro sulfoxide,and pyridinyl-1H-pyrazole-5-carboxylic acid amide compounds were synthesized by carbonyl chloride reacting with corresponding ammonia.
Key intermediate pyridinyl-1H-pyrazole-5-carboxylic acid was synthesized from the reaction of 2,3-dichloropyridine with hydrazine,which was then treated with diethyl maleate,then esterified through halogenation,oxidation,hydrolysis.Carbonyl chloride was synthesized by dichloro sulfoxide,and pyridinyl-1H-pyrazole-5-carboxylic acid amide compounds were synthesized by carbonyl chloride reacting with corresponding ammonia.
2010, 27(9): 1108-1110
doi: 10.3724/SP.J.1095.2010.90786
Abstract:
The title complex Co(bzacen) (bzacen=N,N'-dibenzoylactoneethylenediamine) was prepared and characterized by X-ray diffraction analysis and elemental analysis.In the solid state,the cobalt complex crystallized in monoclinic system,with space group P21/c,a=1.7297(9) nm,b=0.7148(4) nm,c=2.1099(12) nm,β=110.752(2)°,V=1.83807(13) nm3,Dx=1.465 Mg/m3,Z=4,μ=0.090 mm-1, F(000)=844,S=1.01.The structure was refined to R1=0.030 and wR2=0.074 for the observed 3103 reflections with I>2σ(I).The Co atom lies in a slightly distorted square-planar geometry composed of two coordinating nitrogen atoms and two coordinating oxygen atoms.The complex was investigated as precursor for butadiene polymerization,and it showed high activity and high cis-1,4 selectivity when activated by cocatalyst Al2Et2Cl3 or AlEt2Cl.
The title complex Co(bzacen) (bzacen=N,N'-dibenzoylactoneethylenediamine) was prepared and characterized by X-ray diffraction analysis and elemental analysis.In the solid state,the cobalt complex crystallized in monoclinic system,with space group P21/c,a=1.7297(9) nm,b=0.7148(4) nm,c=2.1099(12) nm,β=110.752(2)°,V=1.83807(13) nm3,Dx=1.465 Mg/m3,Z=4,μ=0.090 mm-1, F(000)=844,S=1.01.The structure was refined to R1=0.030 and wR2=0.074 for the observed 3103 reflections with I>2σ(I).The Co atom lies in a slightly distorted square-planar geometry composed of two coordinating nitrogen atoms and two coordinating oxygen atoms.The complex was investigated as precursor for butadiene polymerization,and it showed high activity and high cis-1,4 selectivity when activated by cocatalyst Al2Et2Cl3 or AlEt2Cl.
2010, 27(9): 1111-1113
doi: 10.3724/SP.J.1095.2010.90811
Abstract:
The arginase inhibitor Nω-hydroxy-nor-L-arginine dihydrochloride was successfully synthesized from Nα-Boc-L-glutamine precursor.The expensive reagent was not required in the synthetic process and a seven-step reaction was reduced to a three-step one.Not only was the separation procedure simplified,but also the total yield was increased from 21% to 37%.
The arginase inhibitor Nω-hydroxy-nor-L-arginine dihydrochloride was successfully synthesized from Nα-Boc-L-glutamine precursor.The expensive reagent was not required in the synthetic process and a seven-step reaction was reduced to a three-step one.Not only was the separation procedure simplified,but also the total yield was increased from 21% to 37%.
2010, 27(9): 1114-1116
doi: 10.3724/SP.J.1095.2010.90744
Abstract:
Pulse plating technology was used to plate fine aluminum powder wrapped with nickel on the surface of A3 carbon steel in nickel sulfate bath.A dense and full covered coating with uniform crystallite size could be obtained.The coating prepared from the pulse plating is better than that prepared from a direct current plating in terms of morphology, structure and mechanical stability.Upon annealing at high temperature,Ni-Al alloy was formed.The alloyed coatings could adhere strongly to the steel substrate and the composite coating shows an enhanced resistance to oxidation at high temperatures.
Pulse plating technology was used to plate fine aluminum powder wrapped with nickel on the surface of A3 carbon steel in nickel sulfate bath.A dense and full covered coating with uniform crystallite size could be obtained.The coating prepared from the pulse plating is better than that prepared from a direct current plating in terms of morphology, structure and mechanical stability.Upon annealing at high temperature,Ni-Al alloy was formed.The alloyed coatings could adhere strongly to the steel substrate and the composite coating shows an enhanced resistance to oxidation at high temperatures.
