A new energetic complex, Ni(3,4'-Hbpt)2(Hoba)2(H20)2 (3,4'-Hbpt = 3-(3-pyridyl)- 5-(4'-pyridyl)-l-H-l,2,4-triazole and H2oba = 4,4'-oxybis(benzoic acid)), has been synthesized by hydrothermal reactio...A new energetic complex, Ni(3,4'-Hbpt)2(Hoba)2(H20)2 (3,4'-Hbpt = 3-(3-pyridyl)- 5-(4'-pyridyl)-l-H-l,2,4-triazole and H2oba = 4,4'-oxybis(benzoic acid)), has been synthesized by hydrothermal reaction and characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric analyses and X-ray powder diffraction. Single-crystal X-ray diffraction analysis indicates that the complex belongs to the monoclinic system, space group P2j/c with a = 10.2357(9), b = 24.594(2), c = 10.4225(9)/k, β = 114.0110(10)°, V = 2396.7(4) A3, Dc = 1.460 g/cm3,μ = 0.482 mm-1, Mr = 1053.63, F(000) = 1088, Z = 2, the final R = 0.0358 and wR = 0.0973 with I 〉 2σ(I). Both 3,4'-Hbpt and H2oba ligands adopt monodentate modes linking one Ni(II) ion to form a 0D motif. Furthermore, the 0D motifs are linked into a 3D supramolecular architecture with hydrogen bonds. In addition, the catalytic performance for thermal decomposition of the efficacy of ammonium perchlorate (AP) is explored by differential scanning calorimetry (DSC), which indicates that the complex is a good candidate for a promoter of the thermal decomposition of ammonium perchlorate.展开更多
A new energetic complex,[Co(3,3?-Hbpt)(Htm)]·H_2O(1,3,3?-Hbpt = 3,5-bis(3-pyridyl)-1H-1,2,4-triazole and H_3tm = trimesic acid),has been synthesized by hydrothermal reactions and characterized by single...A new energetic complex,[Co(3,3?-Hbpt)(Htm)]·H_2O(1,3,3?-Hbpt = 3,5-bis(3-pyridyl)-1H-1,2,4-triazole and H_3tm = trimesic acid),has been synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction,elementary analysis,IR spectroscopy,thermogravimetric analysis and X-ray powder diffraction. Single-crystal X-ray diffraction indicates that the complex belongs to triclinic system,space group P 1 with a = 10.0911(1),b = 10.2573(1),c = 10.6393(1) ?,α = 103.793(2),β = 101.041(2),γ = 107.918(3)o,V = 974.9(2) ?~3,Z = 2,D_c = 1.732 g·cm-3,μ = 0.941 mm^(-1),M_r = 508.31,F(000) = 518,the final R = 0.0523 and wR = 0.0935 with I 〉 2σ(I). In the title complex,Co(Ⅱ) ions are connected by Htm2-anions generating 1D ladder-like chains which are linked by 3,3?-Hbpt to form 1D cages. In addition,the thermal decomposition of ammonium perchlorate(AP) with complex 1 was explored by differential scanning calorimetry(DSC). AP is completely decomposed in a shorter time in the presence of complex 1,and the decomposition heat of the mixture is 2.531 kJ·g^(-1),significantly higher than that of pure AP. By Kissinger's method,the ratio of Ea/ln(A) is 11.05 for the mixture,which indicates that complex 1 shows good catalytic activity toward the AP decomposition.展开更多
The precursor of ammonium aluminum carbonate hydroxide was synthesized by using aluminum sulfate(Al2(SO4)3) and ammonium carbonate((NH4)2CO3). The effects of α-Al2O3 seeds and mixture composed of α-Al2O3 and...The precursor of ammonium aluminum carbonate hydroxide was synthesized by using aluminum sulfate(Al2(SO4)3) and ammonium carbonate((NH4)2CO3). The effects of α-Al2O3 seeds and mixture composed of α-Al2O3 and ammonium nitrate, as well as multiplex catalysts (AT) on phase transformation of alumina in sintering process were investigated respectively. The results show that the α-Al2O3 seeds and the mixture of α-Al2O3 and ammonium nitrate can lower the phase transformation temperature of α-Al2O3 to different extents while the particles obtained agglomerate heavily. AT has great potential synergistic effects on the phase transformation of alumina and reduces the phase transformation temperature of α-Al2O3 and the trends of necking-formation between particles. Therefore the dispersion of powder particles is improved significantly.展开更多
In this paper, a new complex inorganic ion exchanger Titanium Phosphate - Ammonium Tungstophosphate (abbreviated as TiP - AWP) was synthesized, whose exchange character and chemical structure were studied, Thiscompoun...In this paper, a new complex inorganic ion exchanger Titanium Phosphate - Ammonium Tungstophosphate (abbreviated as TiP - AWP) was synthesized, whose exchange character and chemical structure were studied, Thiscompound exhibits high exchange capacity and selectivity for Cs+, its exchangecapacity attains 0. 95 mmol/g in the medium of 0. 1 mol/L HNO3, andwhich almost doesn’ t change in the 1 AW imitated waste solution. There areno change in exchange capacity and structure after several times of exchanging,eluting, regenerating, which is of great importance to the separation and uptaking of radio - nuclides. Further more, this exchanger has good thermal andradioactive stability.展开更多
Ammonium and nitrate concentrations were analyzed in near-bottom water and pore water collected from ten stations of the intertidal flat of the Changjiang Estuary during April, July, November and February. The magnitu...Ammonium and nitrate concentrations were analyzed in near-bottom water and pore water collected from ten stations of the intertidal flat of the Changjiang Estuary during April, July, November and February. The magnitudes of the benthic exchange fluxes were determined on the basis of concentration gradients of ammonium and nitrate at the near-bottom water and interstitial water interface in combination with calculations of a modified Fick' s first law. Ammonium fluxes varied from - 5.05 to 1.43 μg/( cm^2·d) and were greatly regulated by the production of ammonium in surface sediments, while nitrate fluxes ranged from - 0. 38 to 1.36 μg/ ( cm^2·d) and were dominated by nitrate concentrations in the tidal water. It was found that ammonium was mainly released from sediments into water columns at most of stations whereas nitrate was mostly diffused from overlying waters to intertidal sediments. In total, 823.75 t/a ammonium-N was passed from intertidal sediments to water while about 521.90 t/a nitrate-N was removed from overlying waters to intertidal sediments. This suggests that intertidal sediments had the significant influence on modulating inorganic nitrogen in the tidal water.展开更多
[Objective]The paper was to study a synthetic method suitable for industrial production of intermediate N-Chloroformyl-N-[4-(trifluoromethoxy)phenyl]methyl carbamate of indoxacarb.[Method]Using 4-trifluoromethoxy anil...[Objective]The paper was to study a synthetic method suitable for industrial production of intermediate N-Chloroformyl-N-[4-(trifluoromethoxy)phenyl]methyl carbamate of indoxacarb.[Method]Using 4-trifluoromethoxy aniline as the starting material,[4-(trifluoromethoxy)phenyl]carbamate was synthesized by homogeneous formylation method without acid-binding agent.Subsequently,it was reacted with sodium methoxide/potassium methoxide by reactive distillation to obtain[4-(trifluoromethoxy)phenyl]carbamate ammonium sodium/potassium,then directly reacted with triphosgene to obtain crude products of N-carbonochloridoyl-N-[4-(trifluoromethoxy)phenyl]carbamate;finally,competing product was obtained by recrystallization.[Result]The intermediate N-chloroformyl-N-[4-(trifluoromethoxy)phenyl]carbamate was synthesized by the method.The content of products was higher than 98%.The yield of product reached above 96%(calculated by 4-trifluoromethoxy aniline).[Conclusion]The method used for the synthesis of intermediate N-chloroformyl-N-[4-(trifluoromethoxy)phenyl]methyl carbamate was simple,with less three wastes,higher safety and lower cost.展开更多
In order to quantitate dencichine in biological samples, a selective and sensitive method for the determination of dencichine in rat plasma based on high-performance liquid chromatography-tandem mass spectrometry (HPL...In order to quantitate dencichine in biological samples, a selective and sensitive method for the determination of dencichine in rat plasma based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed and validated. (l)-2-amino-3-(carboxymethylthio)propionic acid was used as the internal standard (I.S.). After a protein precipitation extraction with acetonitrile, dencichine and the I.S. were chromatographed on an Xterra MS-C18 column. The mobile phase was consisted of 20mmol/L ammonium acetate solution-acetonitrile (35:65, V/V) at a flow rate of 0.2 mL/min. The detection was performed on a triple quadrupole mass via electrospray ionization (ESI) source in the positive mode. The intra- and inter-day precision (relative standard deviation, R.S.D.) values of dencichine were below 6.7%. The extraction recoveries were up 85%. The lower limit of quantification was 20 ng/ml, which was sensitive enough to detect the analyte. The HPLC-MS/MS method was successfully applied to the pharmacokinetic study after an intravenous administration of dencichine in Sprague-Dawley (SD) rat.展开更多
The role of NH4^+ ion confinement in the catalytic etherification of HMF(5-hydroxymethylfurfural) with ethanol to biodiesel additives was evidenced by studying the catalytic behavior of NH4^+-Beta zeolites with SiO2/A...The role of NH4^+ ion confinement in the catalytic etherification of HMF(5-hydroxymethylfurfural) with ethanol to biodiesel additives was evidenced by studying the catalytic behavior of NH4^+-Beta zeolites with SiO2/Al2O3 ratios of 25 and 75.In order to affect the strength and distribution of the acidic sites, as well as the mobility of NH4^+ ions in the zeolites cages, a secondary level of porosity was introduced in the NH4^+-Beta, presenting a different stability versus alkaline treatment, by using a thermal or an ultrasound assisted method.By analyzing the catalytic behavior in these two series of samples with respect to the changes in porosity by nonlocal density functional theory, structure by XRD, amount of acid sites by FT-IR and mobility of NH4^+ cations by measurements of reversible NH4^+ exchange capacity, was evidenced a decrease in catalytic performances both in terms of rate of HMF depletion and productivity to the main products, when confinement of the ammonium ions is lost due to the introduction of mesoporosity.The high capability of ammonium ions release, associated to the mono-dentate configuration,and the minor confinement effect inside the zeolite pore system, due to the more opened pores structure of mesoporous zeolites, hinders both the direct etherification of HMF to EMF [5-(ethoxymethyl)furan-2-carbaldehyde] and the parallel reaction pathway via acetalization, favoring the rapid desorption of the HMFDEA [5-(hydroxymethyl)furfural diethyl acetal] product out of the crystal and the consequent inhibition of the consecutive reactions to EMFDEA [5-(ethoxymethyl)furfural diethyl acetal] and EMF.展开更多
6-Substituted 5,8-O-dimethyl-1,4-naphthoquinones(6-DMNQ),the promising anticancer scaffolds,were selectively generated by oxidative demethylation of 2-substituted 1,4,5,8-tetramethoxynaphthalenes with CAN in EtOAc/H...6-Substituted 5,8-O-dimethyl-1,4-naphthoquinones(6-DMNQ),the promising anticancer scaffolds,were selectively generated by oxidative demethylation of 2-substituted 1,4,5,8-tetramethoxynaphthalenes with CAN in EtOAc/H2O in comparatively high yields.An interesting finding was that apart from the reported electron-withdrawing effects of substituents on position 2 of naphthalene ring,regioselective synthesis of 6-DMNQ was largely dependent on the steric effects in CAN-mediated oxidation.The selective cytotoxicities of 6-DMNQ from the in vitro cell-based assays were exhibited between the cancer cells and normal cells.Moreover,most of sulfur-containing 6-DMNQ derivatives displayed better anticancer activities than the corresponding oxygen-containing ones,which could provide an available strategy for the design of 6-DMNQ derivatives as potential anticancer agents.展开更多
A series of novel quaternary ammonium surfactants containing adamantane were designed and synthesized from 1-adamanta- necarboxylic acid. The structures of target surfactants were confirmed by 1H NMR, elements analysi...A series of novel quaternary ammonium surfactants containing adamantane were designed and synthesized from 1-adamanta- necarboxylic acid. The structures of target surfactants were confirmed by 1H NMR, elements analysis and FFIR. Surface properties of these surfactants were investigated. Due to the lipophilicity of adamantane, the critical micelle concentration (CMC) and C2o values of the synthesized quaternary ammonium surfactants are lower than that of conventional quaternary ammonium surfactants.展开更多
A simple comparative study of synergistic extraction of zinc from ammonium sulfate and ammonium chloride systems with mixtures of Mextral54-100 and tri-nalkylphosphine oxide(TRPO) dissolved in n-heptane was described....A simple comparative study of synergistic extraction of zinc from ammonium sulfate and ammonium chloride systems with mixtures of Mextral54-100 and tri-nalkylphosphine oxide(TRPO) dissolved in n-heptane was described. Various parameters affecting the extraction process were investigated. Experimental results show that extraction from ammonium sulfate is better than that from ammonium chloride under the same conditions owing to the additional complexation between zinc and chloride ions. Total ammonium concentration and pH have a significant effect on zinc extraction efficiency because of the formation of zinc ammine complexes. The synergistic effect is explained by the formation of adduct between zinc chelates and trialkylphosphine oxide. The thermodynamic data show that the extraction reaction is exothermic and stripping is endothermic. Infrared(IR) spectra of the zincloaded organic phases were also examined.展开更多
At the global scale,atmospheric inputs of nitrogen are an important source of the new nitrogen that supports new marine production,especially in oligotrophic open oceans and marginal seas.This study reports quantities...At the global scale,atmospheric inputs of nitrogen are an important source of the new nitrogen that supports new marine production,especially in oligotrophic open oceans and marginal seas.This study reports quantities of atmospheric deposition of dissolved inorganic nitrogen(DIN)to the largest marginal sea in the North Pacific(the oligotrophic South China Sea,SCS)based primarily on rainwater sampling in the open northwestern region(Yongxing Island)from 2013 to 2015,and aerosol sampling from the SCS basin in June 2017.Atmospheric wet and dry deposition of DIN and their potential contributions to productivity were estimated.The volume-weighted mean rainwater concentrations during the wet and dry seasons were 4.9 and 18.1μmol L-1 for N+N(NO3-+NO2-),and 5.7 and 4.0μmol L-1 for NH4+,respectively.Rainwater concentrations of DIN were lower in the marginal seas than in the open ocean.The aerosol NO3-concentration was 1.15±1.18μg m-3 during the wet season,which is slightly lower than reported for the East China Sea and East Sea,but higher than in the Arabian Sea.Monthly wet and dry deposition rates ranged from 0.4-3.9 and 0.4-1.2 mmol m-2 mon-1 for NO3-,and 0.2-1.3 and 0.01-0.02 mmol m-2 mon-1 for NH4+,respectively.The annual wet and dry deposition fluxes of DIN were estimated to be 16.8 and 10.1 mmol m-2yr-1,respectively.Compared to other marginal seas,the SCS receives less atmospheric NO3-inputs than the Yellow Sea,East China Sea,East Sea,and northeastern Mediterranean Sea.The total atmospheric DIN deposition may account for 1.8-11.1%of the nitrogen supporting new production and 0.7-1.8%of the nitrogen supporting primary production.展开更多
基金Supported by the National Natural Science Foundation of China(No.21263019)
文摘A new energetic complex, Ni(3,4'-Hbpt)2(Hoba)2(H20)2 (3,4'-Hbpt = 3-(3-pyridyl)- 5-(4'-pyridyl)-l-H-l,2,4-triazole and H2oba = 4,4'-oxybis(benzoic acid)), has been synthesized by hydrothermal reaction and characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric analyses and X-ray powder diffraction. Single-crystal X-ray diffraction analysis indicates that the complex belongs to the monoclinic system, space group P2j/c with a = 10.2357(9), b = 24.594(2), c = 10.4225(9)/k, β = 114.0110(10)°, V = 2396.7(4) A3, Dc = 1.460 g/cm3,μ = 0.482 mm-1, Mr = 1053.63, F(000) = 1088, Z = 2, the final R = 0.0358 and wR = 0.0973 with I 〉 2σ(I). Both 3,4'-Hbpt and H2oba ligands adopt monodentate modes linking one Ni(II) ion to form a 0D motif. Furthermore, the 0D motifs are linked into a 3D supramolecular architecture with hydrogen bonds. In addition, the catalytic performance for thermal decomposition of the efficacy of ammonium perchlorate (AP) is explored by differential scanning calorimetry (DSC), which indicates that the complex is a good candidate for a promoter of the thermal decomposition of ammonium perchlorate.
基金Supported by the National Natural Science Foundation of China(No.21263019 and 21467022)
文摘A new energetic complex,[Co(3,3?-Hbpt)(Htm)]·H_2O(1,3,3?-Hbpt = 3,5-bis(3-pyridyl)-1H-1,2,4-triazole and H_3tm = trimesic acid),has been synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction,elementary analysis,IR spectroscopy,thermogravimetric analysis and X-ray powder diffraction. Single-crystal X-ray diffraction indicates that the complex belongs to triclinic system,space group P 1 with a = 10.0911(1),b = 10.2573(1),c = 10.6393(1) ?,α = 103.793(2),β = 101.041(2),γ = 107.918(3)o,V = 974.9(2) ?~3,Z = 2,D_c = 1.732 g·cm-3,μ = 0.941 mm^(-1),M_r = 508.31,F(000) = 518,the final R = 0.0523 and wR = 0.0935 with I 〉 2σ(I). In the title complex,Co(Ⅱ) ions are connected by Htm2-anions generating 1D ladder-like chains which are linked by 3,3?-Hbpt to form 1D cages. In addition,the thermal decomposition of ammonium perchlorate(AP) with complex 1 was explored by differential scanning calorimetry(DSC). AP is completely decomposed in a shorter time in the presence of complex 1,and the decomposition heat of the mixture is 2.531 kJ·g^(-1),significantly higher than that of pure AP. By Kissinger's method,the ratio of Ea/ln(A) is 11.05 for the mixture,which indicates that complex 1 shows good catalytic activity toward the AP decomposition.
文摘The precursor of ammonium aluminum carbonate hydroxide was synthesized by using aluminum sulfate(Al2(SO4)3) and ammonium carbonate((NH4)2CO3). The effects of α-Al2O3 seeds and mixture composed of α-Al2O3 and ammonium nitrate, as well as multiplex catalysts (AT) on phase transformation of alumina in sintering process were investigated respectively. The results show that the α-Al2O3 seeds and the mixture of α-Al2O3 and ammonium nitrate can lower the phase transformation temperature of α-Al2O3 to different extents while the particles obtained agglomerate heavily. AT has great potential synergistic effects on the phase transformation of alumina and reduces the phase transformation temperature of α-Al2O3 and the trends of necking-formation between particles. Therefore the dispersion of powder particles is improved significantly.
文摘In this paper, a new complex inorganic ion exchanger Titanium Phosphate - Ammonium Tungstophosphate (abbreviated as TiP - AWP) was synthesized, whose exchange character and chemical structure were studied, Thiscompound exhibits high exchange capacity and selectivity for Cs+, its exchangecapacity attains 0. 95 mmol/g in the medium of 0. 1 mol/L HNO3, andwhich almost doesn’ t change in the 1 AW imitated waste solution. There areno change in exchange capacity and structure after several times of exchanging,eluting, regenerating, which is of great importance to the separation and uptaking of radio - nuclides. Further more, this exchanger has good thermal andradioactive stability.
基金This research is part of the project of the biogeochemical cycling of multi-materials in the Changjiang estuarine and coastal complex ecosystem supported by the National Natural Science Key Foundation of China under contract Nos 40131020 and 49801018 the Tidal Flat Project by Science and Technology Committee of Shanghai under contract No. 04DZ12049+1 种基金 China Postdoctoral Science Foundation under contract No. 2005037135 Shanghai Postdoctoral Science Foundation under contract No.04R214122.
文摘Ammonium and nitrate concentrations were analyzed in near-bottom water and pore water collected from ten stations of the intertidal flat of the Changjiang Estuary during April, July, November and February. The magnitudes of the benthic exchange fluxes were determined on the basis of concentration gradients of ammonium and nitrate at the near-bottom water and interstitial water interface in combination with calculations of a modified Fick' s first law. Ammonium fluxes varied from - 5.05 to 1.43 μg/( cm^2·d) and were greatly regulated by the production of ammonium in surface sediments, while nitrate fluxes ranged from - 0. 38 to 1.36 μg/ ( cm^2·d) and were dominated by nitrate concentrations in the tidal water. It was found that ammonium was mainly released from sediments into water columns at most of stations whereas nitrate was mostly diffused from overlying waters to intertidal sediments. In total, 823.75 t/a ammonium-N was passed from intertidal sediments to water while about 521.90 t/a nitrate-N was removed from overlying waters to intertidal sediments. This suggests that intertidal sediments had the significant influence on modulating inorganic nitrogen in the tidal water.
文摘[Objective]The paper was to study a synthetic method suitable for industrial production of intermediate N-Chloroformyl-N-[4-(trifluoromethoxy)phenyl]methyl carbamate of indoxacarb.[Method]Using 4-trifluoromethoxy aniline as the starting material,[4-(trifluoromethoxy)phenyl]carbamate was synthesized by homogeneous formylation method without acid-binding agent.Subsequently,it was reacted with sodium methoxide/potassium methoxide by reactive distillation to obtain[4-(trifluoromethoxy)phenyl]carbamate ammonium sodium/potassium,then directly reacted with triphosgene to obtain crude products of N-carbonochloridoyl-N-[4-(trifluoromethoxy)phenyl]carbamate;finally,competing product was obtained by recrystallization.[Result]The intermediate N-chloroformyl-N-[4-(trifluoromethoxy)phenyl]carbamate was synthesized by the method.The content of products was higher than 98%.The yield of product reached above 96%(calculated by 4-trifluoromethoxy aniline).[Conclusion]The method used for the synthesis of intermediate N-chloroformyl-N-[4-(trifluoromethoxy)phenyl]methyl carbamate was simple,with less three wastes,higher safety and lower cost.
文摘In order to quantitate dencichine in biological samples, a selective and sensitive method for the determination of dencichine in rat plasma based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed and validated. (l)-2-amino-3-(carboxymethylthio)propionic acid was used as the internal standard (I.S.). After a protein precipitation extraction with acetonitrile, dencichine and the I.S. were chromatographed on an Xterra MS-C18 column. The mobile phase was consisted of 20mmol/L ammonium acetate solution-acetonitrile (35:65, V/V) at a flow rate of 0.2 mL/min. The detection was performed on a triple quadrupole mass via electrospray ionization (ESI) source in the positive mode. The intra- and inter-day precision (relative standard deviation, R.S.D.) values of dencichine were below 6.7%. The extraction recoveries were up 85%. The lower limit of quantification was 20 ng/ml, which was sensitive enough to detect the analyte. The HPLC-MS/MS method was successfully applied to the pharmacokinetic study after an intravenous administration of dencichine in Sprague-Dawley (SD) rat.
文摘The role of NH4^+ ion confinement in the catalytic etherification of HMF(5-hydroxymethylfurfural) with ethanol to biodiesel additives was evidenced by studying the catalytic behavior of NH4^+-Beta zeolites with SiO2/Al2O3 ratios of 25 and 75.In order to affect the strength and distribution of the acidic sites, as well as the mobility of NH4^+ ions in the zeolites cages, a secondary level of porosity was introduced in the NH4^+-Beta, presenting a different stability versus alkaline treatment, by using a thermal or an ultrasound assisted method.By analyzing the catalytic behavior in these two series of samples with respect to the changes in porosity by nonlocal density functional theory, structure by XRD, amount of acid sites by FT-IR and mobility of NH4^+ cations by measurements of reversible NH4^+ exchange capacity, was evidenced a decrease in catalytic performances both in terms of rate of HMF depletion and productivity to the main products, when confinement of the ammonium ions is lost due to the introduction of mesoporosity.The high capability of ammonium ions release, associated to the mono-dentate configuration,and the minor confinement effect inside the zeolite pore system, due to the more opened pores structure of mesoporous zeolites, hinders both the direct etherification of HMF to EMF [5-(ethoxymethyl)furan-2-carbaldehyde] and the parallel reaction pathway via acetalization, favoring the rapid desorption of the HMFDEA [5-(hydroxymethyl)furfural diethyl acetal] product out of the crystal and the consequent inhibition of the consecutive reactions to EMFDEA [5-(ethoxymethyl)furfural diethyl acetal] and EMF.
基金supported by National Natural Science Foundation of China(No.81373274)Ph.D.Programs Foundation of Ministry of Education China(No.20120073110068)Shanghai Biomedical Supporting Funding(No.15431900600)
文摘6-Substituted 5,8-O-dimethyl-1,4-naphthoquinones(6-DMNQ),the promising anticancer scaffolds,were selectively generated by oxidative demethylation of 2-substituted 1,4,5,8-tetramethoxynaphthalenes with CAN in EtOAc/H2O in comparatively high yields.An interesting finding was that apart from the reported electron-withdrawing effects of substituents on position 2 of naphthalene ring,regioselective synthesis of 6-DMNQ was largely dependent on the steric effects in CAN-mediated oxidation.The selective cytotoxicities of 6-DMNQ from the in vitro cell-based assays were exhibited between the cancer cells and normal cells.Moreover,most of sulfur-containing 6-DMNQ derivatives displayed better anticancer activities than the corresponding oxygen-containing ones,which could provide an available strategy for the design of 6-DMNQ derivatives as potential anticancer agents.
基金support by the Major Program of Guangdong University of Technology (No.405095220)
文摘A series of novel quaternary ammonium surfactants containing adamantane were designed and synthesized from 1-adamanta- necarboxylic acid. The structures of target surfactants were confirmed by 1H NMR, elements analysis and FFIR. Surface properties of these surfactants were investigated. Due to the lipophilicity of adamantane, the critical micelle concentration (CMC) and C2o values of the synthesized quaternary ammonium surfactants are lower than that of conventional quaternary ammonium surfactants.
基金financially supported by the National Basic Research Program of China (No. 2014CB643404)the National Natural Science Foundation of China (Nos.51174104, 51304093, and 51364022)
文摘A simple comparative study of synergistic extraction of zinc from ammonium sulfate and ammonium chloride systems with mixtures of Mextral54-100 and tri-nalkylphosphine oxide(TRPO) dissolved in n-heptane was described. Various parameters affecting the extraction process were investigated. Experimental results show that extraction from ammonium sulfate is better than that from ammonium chloride under the same conditions owing to the additional complexation between zinc and chloride ions. Total ammonium concentration and pH have a significant effect on zinc extraction efficiency because of the formation of zinc ammine complexes. The synergistic effect is explained by the formation of adduct between zinc chelates and trialkylphosphine oxide. The thermodynamic data show that the extraction reaction is exothermic and stripping is endothermic. Infrared(IR) spectra of the zincloaded organic phases were also examined.
基金supported by the National Basic R&D Program of China(Grant No.2015CB954001)the National Natural Science Foundation of China(Grant No.41876080)。
文摘At the global scale,atmospheric inputs of nitrogen are an important source of the new nitrogen that supports new marine production,especially in oligotrophic open oceans and marginal seas.This study reports quantities of atmospheric deposition of dissolved inorganic nitrogen(DIN)to the largest marginal sea in the North Pacific(the oligotrophic South China Sea,SCS)based primarily on rainwater sampling in the open northwestern region(Yongxing Island)from 2013 to 2015,and aerosol sampling from the SCS basin in June 2017.Atmospheric wet and dry deposition of DIN and their potential contributions to productivity were estimated.The volume-weighted mean rainwater concentrations during the wet and dry seasons were 4.9 and 18.1μmol L-1 for N+N(NO3-+NO2-),and 5.7 and 4.0μmol L-1 for NH4+,respectively.Rainwater concentrations of DIN were lower in the marginal seas than in the open ocean.The aerosol NO3-concentration was 1.15±1.18μg m-3 during the wet season,which is slightly lower than reported for the East China Sea and East Sea,but higher than in the Arabian Sea.Monthly wet and dry deposition rates ranged from 0.4-3.9 and 0.4-1.2 mmol m-2 mon-1 for NO3-,and 0.2-1.3 and 0.01-0.02 mmol m-2 mon-1 for NH4+,respectively.The annual wet and dry deposition fluxes of DIN were estimated to be 16.8 and 10.1 mmol m-2yr-1,respectively.Compared to other marginal seas,the SCS receives less atmospheric NO3-inputs than the Yellow Sea,East China Sea,East Sea,and northeastern Mediterranean Sea.The total atmospheric DIN deposition may account for 1.8-11.1%of the nitrogen supporting new production and 0.7-1.8%of the nitrogen supporting primary production.