Three zincand cobaltcoordination polymers,namely{[Zn_(2)(μ_(6)-adip)(phen)_(2)]·4H_(2)O}_(n)(1),{[Co_(2)(μ_(6)-adip)(bipy)_(2)]·4H_(2)O}_(n)(2),and[Co_(2)(μ4-adip)(μ-bpa)_(2)]_(n)(3)have been constructed...Three zincand cobaltcoordination polymers,namely{[Zn_(2)(μ_(6)-adip)(phen)_(2)]·4H_(2)O}_(n)(1),{[Co_(2)(μ_(6)-adip)(bipy)_(2)]·4H_(2)O}_(n)(2),and[Co_(2)(μ4-adip)(μ-bpa)_(2)]_(n)(3)have been constructed hydrothermally using H4adip(H4adip=5,5′-azanediyldiisophthalic acid),phen(phen=1,10-phenanthroline),bipy(bipy=2,2′-bipyridine),bpa(bpa=bis(4-pyridyl)amine),and zinc and cobalt chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and single-crystal X-ray diffrac-tion analyses.Single-crystal X-ray diffraction analyses revealed that three compounds crystallize in the orthorhom-bic system Pnna(1 and 2)or P21212(3)space groups.All compounds exhibit 3D frameworks.The catalytic perfor-mances in the Henry reaction of these compounds were investigated.Compound 3 exhibited an effective catalytic activity in the Henry reaction at 70℃.CCDC:2339391,1;2339392,2;2339393,3.展开更多
Self assembled monolayers (SAMs) of 1-tetradecylphosphonic acids (TDPA, CH3(CH2)13P(O)(OH)2 ) were formed on the 2024 aluminum alloy surface in TDPA-containing ethanol-water solutions with different water co...Self assembled monolayers (SAMs) of 1-tetradecylphosphonic acids (TDPA, CH3(CH2)13P(O)(OH)2 ) were formed on the 2024 aluminum alloy surface in TDPA-containing ethanol-water solutions with different water content. The adsorption and corrosion protection properties of the SAMs for 2024 alloy in 0.1 mol/L H2SO4 solution were examined and characterized by potentiodynamic polarization, electrochemical impedance spectrum (EIS), Fourier transformed infrared spectroscopy (FTIR), Auger electron spectra (AES) and atomic force microscopy (AFM). FTIR and AES results show that the TDPA molecules were successfully adsorbed on the 2024 aluminum alloy surface, and the density of the SAMs increased with the increasing water content in the assembly solution. The results of electrochemical studies and corrosion morphologies observed by AFM show that a 4 h modification resulted in maximal inhibition efficiency, and the higher the water content in the assembly solution is, the better the inhibition performance of the SAMs can be achieved. The effect of water content in TDPA solutions on the performance of the SAMs is related to the hydration reaction of the metal surface.展开更多
We tested the utility of chemical marking techniques in the juvenile black rockfish Sebastes schlegelii. Juveniles (30-40 mm total length) were immersed in a range of tetracycline hydrochloride (TC) solutions at c...We tested the utility of chemical marking techniques in the juvenile black rockfish Sebastes schlegelii. Juveniles (30-40 mm total length) were immersed in a range of tetracycline hydrochloride (TC) solutions at concentrations ranging from 300 to 500 mg/L, and alizarin complexone (ALC) solutions at concentrations ranging from 200 to 400 mg/L in filtered sea water (salinity of 30) for 24 h, respectively. Otoliths (sagittae, asteriscus), scales, fin rays (dorsal, pectoral, ventral, anal, and caudal fin rays), and fin spines (dorsal, ventral, and anal fin spines) were sampled and used to detect fluorescent marks after a 60-day growth experiment. With the exception of 300 mg/L TC, acceptable marks were produced in the otoliths and fin spines by all concentrations of TC and ALC. In particular, we observed clearly visible marks in the sagittae, asteriscus, and fin spines under normal light at concentrations of200~00 mg/L, 250-400 mg/L, and 250-400 mg/L ALC, respectively. Scales and fin rays had acceptable marks at much higher concentrations (_〉350 mg/L TC, 〉250 mg/L ALC for scales and _〉350 mg/L TC, 〉300 mg/L ALC for fin rays). The best mark quality (i.e., acceptable marks were observed in all sampled structures after immersion marking) were obtained following immersion in TC at between 350-500 rag/L, and ALC between 300-400 mg/L. In addition, there was no significant difference in survival and growth of TC and ALC marked fish compared to their controls up to 60 days post-marking (P〉0.05).展开更多
The protected tetrapeptide, N-o-Ns-N ( Me ) -Val-N ( Me ) -Val-N ( Me ) -Val- N ( Me ) -Phe- OtBu, was prepared from L-valine and L-phenylalanine. Ted-butyl acetate and HClO4 were used to protect carbonyl grou...The protected tetrapeptide, N-o-Ns-N ( Me ) -Val-N ( Me ) -Val-N ( Me ) -Val- N ( Me ) -Phe- OtBu, was prepared from L-valine and L-phenylalanine. Ted-butyl acetate and HClO4 were used to protect carbonyl group, o-nitrobenzenesulfonyl chloride and triethyl amine were used to protect amino group, and N-alkylation was finished with iodomethane. Then the protected amino acid was turned into acid chloride which was taken as coupling reagent. After 14 steps, such as protection, alkylation, deprotection and coupling, the protected tetrapeptide was obtained with a yield of 26.9%. The structures of intermediates and target compound were identified with NMR spectra and high resolution mass spectra.展开更多
The cluster compound [Mo4S4 (μ-O2CC6H5)2(dtp)4] (dtp = S2P (OEt)2)was obtained by the ligand substitution reaction of tetranuclear molybdenum cluster [Mo4S4(μ-dtp)2(dtp)4] in the mixed solvent of acetone, ethanol an...The cluster compound [Mo4S4 (μ-O2CC6H5)2(dtp)4] (dtp = S2P (OEt)2)was obtained by the ligand substitution reaction of tetranuclear molybdenum cluster [Mo4S4(μ-dtp)2(dtp)4] in the mixed solvent of acetone, ethanol and water in the presence of C6H5CO2Na. It is monoclinic and crystallizesin space group C2/c, Mr =1495. 09, a=12. 175 (5) , b=22. 01 (1) , c=20.875(9) ,β=99. 04(4)°; V=5570(5) ; Z=4; Dc= 1. 78g/cm3;μ(MoKα) = 14. 52 cm-1; F(000) =2984. Final R factor is 0. 066. The result reveals that the [Mo4S4] cluster core and t-(dtp)1ligands are retained and onlyμ-bridged (dtp)1- ligands are substituted by (C6H5CO2)1in the substitution reaction, thus producing the title cluster compound,the structure of which contains two species of bidentate ligand.展开更多
The growth kinetics of microarc oxidation(MAO)coatings on Ti6Al4V alloy was studied by designing an electrolyte with low PO_(4)^(3−)content and high B_(4)O_(7)^(2−)content,using scanning electron microscopy,transmissi...The growth kinetics of microarc oxidation(MAO)coatings on Ti6Al4V alloy was studied by designing an electrolyte with low PO_(4)^(3−)content and high B_(4)O_(7)^(2−)content,using scanning electron microscopy,transmission electron microscopy,X-ray diffraction,and potentiodynamic polarization.The results showed that B_(4)O_(7)^(2−)increased the spark intensity and dissolved most of the oxides at high temperatures.Then,a thicker barrier layer at the coating/substrate interface was produced,which increased the polarization resistance of the coating.PO_(4)^(3−)at a low concentration also promoted the uniform growth of the MAO coating and the formation of hat-shaped holes in the outer deposition layer.The thickness of the MAO coatings obtained in Na_(2)B_(4)O_(7) electrolytes exhibited an exponential increase with time at spark discharge stage,while that of the MAO coating obtained in phosphate–tetraborate electrolytes showed a linear trend as the PO_(4)^(3−)content increased.展开更多
The microcapsules with cores of ethylenediamine tetraacetic acid tetrasodium salt(Na4-EDTA)and walls of polyurea were synthesized via an interfacial polycondensation reaction with 2,4-tolylene diisocyanate as an oil-s...The microcapsules with cores of ethylenediamine tetraacetic acid tetrasodium salt(Na4-EDTA)and walls of polyurea were synthesized via an interfacial polycondensation reaction with 2,4-tolylene diisocyanate as an oil-soluble monomer and diethyl triamine as a water-soluble monomer.Various manufacturing parameters,including the amount of emulsifier,agitation speed,stirring time and ratios of the wall materials to core materials,were altered to optimize process variables during the synthesis of microcapsules,and the effects of these parameters on the characteristics of the microcapsules were examined.The structure,morphology,mean particle size and size distribution were characterized by optical microscope and scanning electron microscopy(SEM),showing that the mean diameter of optimal microspheres was approximately 6μm,and microcapsules were spherical.In vitro release of Na4-EDTA from these microcapsules was performed in distilled water.Under the optimal preparation conditions, the Na4-EDTA release profiles were biphasic with a burst release followed by a gradual release phase.After an initial burst,a continuous Na4-EDTA release was up to 5-7 days.The optimal synthesis conditions for the microcapsules with stable,good morphology and good controlled-release properties were as follows:emulsifier Span-80 10% (by mass),agitation speed 900 r·min1,stirring time 30 min,and the ratio of the wall materials to core materials 0.15.展开更多
A trinudear Mn(II) coordination complex Mna (HEDTA)2-10H20 (EDTA=ethylene diamine tetraacetic acid) 1 has been synthesized and characterized by X-ray crystal structure determination. In addition, IR spectrum, th...A trinudear Mn(II) coordination complex Mna (HEDTA)2-10H20 (EDTA=ethylene diamine tetraacetic acid) 1 has been synthesized and characterized by X-ray crystal structure determination. In addition, IR spectrum, thermogravimetric analysis, electron paramagnetic resonance (EPR) spectra and magnetic susceptibility of this complex are discussed. X-ray determination indicates that six- and seven-coordinate modes between Mn(Yl) and H4EDTA exist alternately in 1. Furthermore, detailed discussion of magnetic ordering in tile temperature range of 2-300 K reveals the antiferromagnetic interactions in the complex.展开更多
The microstructure, IR spectrum, as well as rotation dynamics of water molecule in sodium tetrafluoroborate (NaBF4)/water mixture at room temperatures were studied with molecular dynamics simulation. Different conce...The microstructure, IR spectrum, as well as rotation dynamics of water molecule in sodium tetrafluoroborate (NaBF4)/water mixture at room temperatures were studied with molecular dynamics simulation. Different concentrations of water (6.25%, 25.0%, 50.0%, 75.0%, 90.0%, and 99.6%) in NaBF4/water mixture were simulated to understand the structure and dynamics. It was shown that water molecules tend to be isolated from each other in mixtures with more ions than water molecules in both liquids. With increase of the molar fraction of water in the mixture, the rotation bands and the bending bands of water display red shift whereas the O-H stretch bands show blue shift, and the decay of the reorientation correlation function becomes slower. This suggests that the molecules are hindered and their motions are difficult and slow, due to the hydrogen-bond interactions and the inharmonic interactions between the interor intra-molecular modes.展开更多
Fine soil generated from the soil washing process can be the second problem, as contaminants are concentrated in the fine soil, and also took the difficult forms to treat because soluble and exchangeable fractions are...Fine soil generated from the soil washing process can be the second problem, as contaminants are concentrated in the fine soil, and also took the difficult forms to treat because soluble and exchangeable fractions are already removed by soil washing process; therefore, the fine soil is indicated to hazardous waste, and discarded in hazardous waste landfill. Thus, this research would be performed that arsenic and heavy metals formed difficult to remove in the fine soil were converted to more treatable fractions with chelating agents. Moreover, feasibility study to apply the second remediation targeted to the fine soil inquired. As a result, the chelating agent was decided 50 mM Na2EDTA, and it could develop the complex. In addition, the result of sequential extraction showed that Mn/Fe-oxide fraction, comprised about 28% of amount at first, was decreased about 16%, and organic fraction, consisted approximately 20%, was also decreased about 11%, while exchangeable fraction and carbonate fraction were increased. This result means that the difficult fractions removed could change fractions) by chelating agent. This research can provide the possibility hazardous waste because of difficulty to remediate. the more treatable fractions (exchangeable and carbonate to treat the fine soil, although the fine soil was regarded to展开更多
文摘Three zincand cobaltcoordination polymers,namely{[Zn_(2)(μ_(6)-adip)(phen)_(2)]·4H_(2)O}_(n)(1),{[Co_(2)(μ_(6)-adip)(bipy)_(2)]·4H_(2)O}_(n)(2),and[Co_(2)(μ4-adip)(μ-bpa)_(2)]_(n)(3)have been constructed hydrothermally using H4adip(H4adip=5,5′-azanediyldiisophthalic acid),phen(phen=1,10-phenanthroline),bipy(bipy=2,2′-bipyridine),bpa(bpa=bis(4-pyridyl)amine),and zinc and cobalt chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and single-crystal X-ray diffrac-tion analyses.Single-crystal X-ray diffraction analyses revealed that three compounds crystallize in the orthorhom-bic system Pnna(1 and 2)or P21212(3)space groups.All compounds exhibit 3D frameworks.The catalytic perfor-mances in the Henry reaction of these compounds were investigated.Compound 3 exhibited an effective catalytic activity in the Henry reaction at 70℃.CCDC:2339391,1;2339392,2;2339393,3.
基金Project(Q20120110)supported by Youth Foundation of Hubei Provincial Education Bureau,ChinaProject(2009CDB347)supported by the Hubei Provincial Natural Science Foundation,ChinaProject(51001045)supported by the National Natural Science Foundation of China
文摘Self assembled monolayers (SAMs) of 1-tetradecylphosphonic acids (TDPA, CH3(CH2)13P(O)(OH)2 ) were formed on the 2024 aluminum alloy surface in TDPA-containing ethanol-water solutions with different water content. The adsorption and corrosion protection properties of the SAMs for 2024 alloy in 0.1 mol/L H2SO4 solution were examined and characterized by potentiodynamic polarization, electrochemical impedance spectrum (EIS), Fourier transformed infrared spectroscopy (FTIR), Auger electron spectra (AES) and atomic force microscopy (AFM). FTIR and AES results show that the TDPA molecules were successfully adsorbed on the 2024 aluminum alloy surface, and the density of the SAMs increased with the increasing water content in the assembly solution. The results of electrochemical studies and corrosion morphologies observed by AFM show that a 4 h modification resulted in maximal inhibition efficiency, and the higher the water content in the assembly solution is, the better the inhibition performance of the SAMs can be achieved. The effect of water content in TDPA solutions on the performance of the SAMs is related to the hydration reaction of the metal surface.
基金Supported by the Special Fund for Agro-Scientific Research in the Public Interest(No.201003068)the National Natural Science Foundation of China(Nos.31172447,41176117)
文摘We tested the utility of chemical marking techniques in the juvenile black rockfish Sebastes schlegelii. Juveniles (30-40 mm total length) were immersed in a range of tetracycline hydrochloride (TC) solutions at concentrations ranging from 300 to 500 mg/L, and alizarin complexone (ALC) solutions at concentrations ranging from 200 to 400 mg/L in filtered sea water (salinity of 30) for 24 h, respectively. Otoliths (sagittae, asteriscus), scales, fin rays (dorsal, pectoral, ventral, anal, and caudal fin rays), and fin spines (dorsal, ventral, and anal fin spines) were sampled and used to detect fluorescent marks after a 60-day growth experiment. With the exception of 300 mg/L TC, acceptable marks were produced in the otoliths and fin spines by all concentrations of TC and ALC. In particular, we observed clearly visible marks in the sagittae, asteriscus, and fin spines under normal light at concentrations of200~00 mg/L, 250-400 mg/L, and 250-400 mg/L ALC, respectively. Scales and fin rays had acceptable marks at much higher concentrations (_〉350 mg/L TC, 〉250 mg/L ALC for scales and _〉350 mg/L TC, 〉300 mg/L ALC for fin rays). The best mark quality (i.e., acceptable marks were observed in all sampled structures after immersion marking) were obtained following immersion in TC at between 350-500 rag/L, and ALC between 300-400 mg/L. In addition, there was no significant difference in survival and growth of TC and ALC marked fish compared to their controls up to 60 days post-marking (P〉0.05).
文摘The protected tetrapeptide, N-o-Ns-N ( Me ) -Val-N ( Me ) -Val-N ( Me ) -Val- N ( Me ) -Phe- OtBu, was prepared from L-valine and L-phenylalanine. Ted-butyl acetate and HClO4 were used to protect carbonyl group, o-nitrobenzenesulfonyl chloride and triethyl amine were used to protect amino group, and N-alkylation was finished with iodomethane. Then the protected amino acid was turned into acid chloride which was taken as coupling reagent. After 14 steps, such as protection, alkylation, deprotection and coupling, the protected tetrapeptide was obtained with a yield of 26.9%. The structures of intermediates and target compound were identified with NMR spectra and high resolution mass spectra.
文摘The cluster compound [Mo4S4 (μ-O2CC6H5)2(dtp)4] (dtp = S2P (OEt)2)was obtained by the ligand substitution reaction of tetranuclear molybdenum cluster [Mo4S4(μ-dtp)2(dtp)4] in the mixed solvent of acetone, ethanol and water in the presence of C6H5CO2Na. It is monoclinic and crystallizesin space group C2/c, Mr =1495. 09, a=12. 175 (5) , b=22. 01 (1) , c=20.875(9) ,β=99. 04(4)°; V=5570(5) ; Z=4; Dc= 1. 78g/cm3;μ(MoKα) = 14. 52 cm-1; F(000) =2984. Final R factor is 0. 066. The result reveals that the [Mo4S4] cluster core and t-(dtp)1ligands are retained and onlyμ-bridged (dtp)1- ligands are substituted by (C6H5CO2)1in the substitution reaction, thus producing the title cluster compound,the structure of which contains two species of bidentate ligand.
文摘The growth kinetics of microarc oxidation(MAO)coatings on Ti6Al4V alloy was studied by designing an electrolyte with low PO_(4)^(3−)content and high B_(4)O_(7)^(2−)content,using scanning electron microscopy,transmission electron microscopy,X-ray diffraction,and potentiodynamic polarization.The results showed that B_(4)O_(7)^(2−)increased the spark intensity and dissolved most of the oxides at high temperatures.Then,a thicker barrier layer at the coating/substrate interface was produced,which increased the polarization resistance of the coating.PO_(4)^(3−)at a low concentration also promoted the uniform growth of the MAO coating and the formation of hat-shaped holes in the outer deposition layer.The thickness of the MAO coatings obtained in Na_(2)B_(4)O_(7) electrolytes exhibited an exponential increase with time at spark discharge stage,while that of the MAO coating obtained in phosphate–tetraborate electrolytes showed a linear trend as the PO_(4)^(3−)content increased.
基金Supported by the National Natural Science Foundation of China(30571117) the Important Sci-Tech Special Project of Guangdong Province China(2006A36703004 2008A030202004)
文摘The microcapsules with cores of ethylenediamine tetraacetic acid tetrasodium salt(Na4-EDTA)and walls of polyurea were synthesized via an interfacial polycondensation reaction with 2,4-tolylene diisocyanate as an oil-soluble monomer and diethyl triamine as a water-soluble monomer.Various manufacturing parameters,including the amount of emulsifier,agitation speed,stirring time and ratios of the wall materials to core materials,were altered to optimize process variables during the synthesis of microcapsules,and the effects of these parameters on the characteristics of the microcapsules were examined.The structure,morphology,mean particle size and size distribution were characterized by optical microscope and scanning electron microscopy(SEM),showing that the mean diameter of optimal microspheres was approximately 6μm,and microcapsules were spherical.In vitro release of Na4-EDTA from these microcapsules was performed in distilled water.Under the optimal preparation conditions, the Na4-EDTA release profiles were biphasic with a burst release followed by a gradual release phase.After an initial burst,a continuous Na4-EDTA release was up to 5-7 days.The optimal synthesis conditions for the microcapsules with stable,good morphology and good controlled-release properties were as follows:emulsifier Span-80 10% (by mass),agitation speed 900 r·min1,stirring time 30 min,and the ratio of the wall materials to core materials 0.15.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.20490210,10574047)the Doctor Foundation of China(Grant No.20030487003)
文摘A trinudear Mn(II) coordination complex Mna (HEDTA)2-10H20 (EDTA=ethylene diamine tetraacetic acid) 1 has been synthesized and characterized by X-ray crystal structure determination. In addition, IR spectrum, thermogravimetric analysis, electron paramagnetic resonance (EPR) spectra and magnetic susceptibility of this complex are discussed. X-ray determination indicates that six- and seven-coordinate modes between Mn(Yl) and H4EDTA exist alternately in 1. Furthermore, detailed discussion of magnetic ordering in tile temperature range of 2-300 K reveals the antiferromagnetic interactions in the complex.
基金The authors are grateful to Professor Jiu-shu Shao at Beijing Normal University for his encourage and help reading the manuscript. We also would like to thank Prof. Jian-min Tao and Guo-bao Li for their kind help. This work was supported by the National Natural Science Foundation of China (No.50564006), the Key program of Natural Science Foundation of Yunnan Provine (No.2005EOOO4Z), the Natural Science Foundation of Yunnan Provine (No.2008E0049M), the Foundation of the Education Department of Yunnan Province (No.07Z40082), and the Foundation of Kunming University of Science and Technology (No.2007-16).
文摘The microstructure, IR spectrum, as well as rotation dynamics of water molecule in sodium tetrafluoroborate (NaBF4)/water mixture at room temperatures were studied with molecular dynamics simulation. Different concentrations of water (6.25%, 25.0%, 50.0%, 75.0%, 90.0%, and 99.6%) in NaBF4/water mixture were simulated to understand the structure and dynamics. It was shown that water molecules tend to be isolated from each other in mixtures with more ions than water molecules in both liquids. With increase of the molar fraction of water in the mixture, the rotation bands and the bending bands of water display red shift whereas the O-H stretch bands show blue shift, and the decay of the reorientation correlation function becomes slower. This suggests that the molecules are hindered and their motions are difficult and slow, due to the hydrogen-bond interactions and the inharmonic interactions between the interor intra-molecular modes.
文摘Fine soil generated from the soil washing process can be the second problem, as contaminants are concentrated in the fine soil, and also took the difficult forms to treat because soluble and exchangeable fractions are already removed by soil washing process; therefore, the fine soil is indicated to hazardous waste, and discarded in hazardous waste landfill. Thus, this research would be performed that arsenic and heavy metals formed difficult to remove in the fine soil were converted to more treatable fractions with chelating agents. Moreover, feasibility study to apply the second remediation targeted to the fine soil inquired. As a result, the chelating agent was decided 50 mM Na2EDTA, and it could develop the complex. In addition, the result of sequential extraction showed that Mn/Fe-oxide fraction, comprised about 28% of amount at first, was decreased about 16%, and organic fraction, consisted approximately 20%, was also decreased about 11%, while exchangeable fraction and carbonate fraction were increased. This result means that the difficult fractions removed could change fractions) by chelating agent. This research can provide the possibility hazardous waste because of difficulty to remediate. the more treatable fractions (exchangeable and carbonate to treat the fine soil, although the fine soil was regarded to