Two new metal-organic complexes [Cd2(1,4-BDC)(4-pytyp)(H2O)4]·(1,4-BDC)(1) and [Cu2(1,4-BDC)(4-pytyp)2(H2O)2]·(1,4-BDC)·8H2O(2)(4-pytyp = 4'-(4''-pyridyl)-2,2':6',2''-terp...Two new metal-organic complexes [Cd2(1,4-BDC)(4-pytyp)(H2O)4]·(1,4-BDC)(1) and [Cu2(1,4-BDC)(4-pytyp)2(H2O)2]·(1,4-BDC)·8H2O(2)(4-pytyp = 4'-(4''-pyridyl)-2,2':6',2''-terpyridine, 1,4-H2 BDC = 1,4-benzenedicarboxylic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis, infrared analysis and X-ray single-crystal diffraction. The scrutiny of single-crystal structure reveals that complex 1 forms to a 3D supramolecular network linked by π-π stacking interactions and hydrogen bonds. X-ray diffraction analysis reveals that complex 2 exhibits a 3D supramolecular network linked through complicated hydrogen bonds. The thermogravimetric analysis and photoluminescent properties of 1 and 2 are discussed in detail.展开更多
Two new complexes [Mn(DHTA)(PLQ)]n(1) and{[Co2(DHTA)(phen)2(H2 O)6]· DHTA}n(2)(H2 DHTA = 2,5-dihydroxy-1,4-benzenedicarboxylic acid, PLQ = 1,10-phenanthroline-5,6-quinone, phen = 1,10-phenanthroline) have been hy...Two new complexes [Mn(DHTA)(PLQ)]n(1) and{[Co2(DHTA)(phen)2(H2 O)6]· DHTA}n(2)(H2 DHTA = 2,5-dihydroxy-1,4-benzenedicarboxylic acid, PLQ = 1,10-phenanthroline-5,6-quinone, phen = 1,10-phenanthroline) have been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, fluorescence spectrum, single-crystal and power X-ray diffraction. Complex 1 exhibits a two-dimensional(2 D) network, which was stabilized through O–H···O hydrogen bonding interactions. Complex 2 shows a zero-dimensional structure, which was further extended into a three-dimensional supramolecular structure through O–H···O hydrogen bonds and π-π interactions.展开更多
A new complex[Mn(DHTA)(bipy)0.5]n(1,H2DHTA=2,5-dihydroxy-1,4-benzenedicarboxylic acid,bipy=2,2΄-bipyridine)was hydrothermally synthesized and structurally characterized by elemental analysis,IR spectrum,single-crystal...A new complex[Mn(DHTA)(bipy)0.5]n(1,H2DHTA=2,5-dihydroxy-1,4-benzenedicarboxylic acid,bipy=2,2΄-bipyridine)was hydrothermally synthesized and structurally characterized by elemental analysis,IR spectrum,single-crystal and power X-ray diffraction.It belongs to monoclinic system,C2/c space group with a=12.874(13),b=11.302(12),c=17.352(18)Å,β=101.574(15)°,V=2474(4)Å3 and Z=4.It displays a one-dimensional zigzag chain-like structure,which was further extended into a three-dimensional supramolecular structure by hydrogen bonds andπ-πinteractions.Moreover,we analyzed Natural Bond Orbital(NBO)of 1 in using the PBE0/LANL2DZ method built in Gaussian 03 Program.The calculation results show the obvious covalent interaction between the coordinated atoms and Mn(Ⅱ)ion.展开更多
The work herein employed a rotating packed bed(RPB)to intensify the sulfonation process of 1,4-diaminoanthraquinone leuco(DL)in an attempt to improve the yield of the product 1,4-diaminoanthra quinone-2-sulfonic acid(...The work herein employed a rotating packed bed(RPB)to intensify the sulfonation process of 1,4-diaminoanthraquinone leuco(DL)in an attempt to improve the yield of the product 1,4-diaminoanthra quinone-2-sulfonic acid(DSA).First,the effects of operating conditions in a stirred tank reactor(STR),including stirring speed,chlorosulfonic acid/DL molar ratio(η),solvent/DL mass ratio(ζ),reaction temperature and dropping speed of chlorosulfonic acid,on the yield of DSA were investigated.The yield of DSA can reach 87.34%under the optimal operating conditions:stirring speed of 500 r·min^(-1),ηof 4.5,ζof 7,reaction temperature of 150℃,dropping speed of 0.61 ml·min^(-1).In addition,the kinetics of the sulfonation process via the shrinking core model revealed that the reaction is controlled by diffusion via a product layer under the reaction temperature of 140℃.Furthermore,the RPB was employed to intensify the mass transfer between liquid and solid phases during the sulfonation reaction process.The results showed that the DSA yield of 92.69%obtained by RPB was 5.35%higher than that by STR,indicating that RPB can significantly intensify the mass transfer in the liquid-solid phase sulfonation reaction process.展开更多
The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl pho...The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl phosphate(TBP), di(2-ethylhexyl) phosphoric acid(D2EHPA) and TBP + D2EHPA dissolved in 1-octanol were investigated, respectively. The influences of the initial concentrations of TBP, D2EHPA and TBP + D2EHPA on distribution ratio(D) were discussed, as well as the reactive extraction mechanism were proposed. The obvious intensification effect was observed when the mixture of TBP and D2EHPA was used as extractant. The best extraction conditions were found to be of the molar ratio of D2EHPA and TBP at 2:1 and the equilibrium aqueous pH at 3.50-4.50. D values increased with the increase of the total concentration of TBP and D2EHPA in 1-octanol. Especially, the analysis on the extraction mechanisms clearly indicate(i) TBP in 1-octanol shows negligible reactive extraction toward 4-HP,(ii) D2EHPA in 1-octanol exhibits moderate extraction effect by forming 4-HP:D2EHPA(1:1) and 4-HP:2D2EHPA(1:2) type complexes, while(iii) D2EHPA in TBP/1-octanol demonstrates the maximum distribution ratio with the 4-HP:D2EHPA(1:1) type complex domination. The discussion provides new insights on the mechanism and opens a new way for the intensified extraction of amphoteric organic compounds by using the mixture of multiple extractants in the diluent.展开更多
Activated carbons calcined at 400˚C and 600˚C (AC-400 and AC-600), prepared using palm nuts, collected in the town of Franceville in Gabon, were used to study the dynamic adsorption of MnO<sub>4</sub>-<...Activated carbons calcined at 400˚C and 600˚C (AC-400 and AC-600), prepared using palm nuts, collected in the town of Franceville in Gabon, were used to study the dynamic adsorption of MnO<sub>4</sub>-</sup> ions in acidic media on fixed bed column and on the kinetic modeling of experimental data of breakthrough curves of MnO<sub>4</sub>-</sup> ions obtained. Results on the adsorption of MnO<sub>4</sub>-</sup> ions in fixed-bed dynamics obtained on AC-400 and AC-600 adsorbents beds indicated that the AC-400 bed appears to be the most efficient in removing MnO<sub>4</sub>-</sup> ions in acidic media. Indeed, the adsorbed amounts, the adsorbed capacities at saturation and the elimination percentage of MnO<sub>4</sub>-</sup> ions obtained with AC-400 (31.24 mg;52.06 mg·g<sup>-1</sup> and 41.65% respectively) were higher compared to those obtained with AC-600 (9.87 mg;16.45 mg·g<sup>-1</sup> and 17.79% respectively). The breakthrough curves kinetic modeling revealed that the Thomas model and the pseudo-first-order kinetic model were the most suitable models to describe the adsorption of MnO<sub>4</sub>-</sup> ions on adsorbents studied in our experimental conditions. The results of the intraparticle diffusion model showed that intraparticle diffusion was involved in the adsorption mechanism of MnO<sub>4</sub>-</sup> ions on investigated adsorbents and was not the limiting step and the only process controlling MnO<sub>4</sub>-</sup> ions adsorption. In contrast to AC-400, the intraparticle diffusion on AC-600 bed plays an important role in the adsorption mechanism of MnO<sub>4</sub>-</sup> ions.展开更多
Many approaches to neurodegenerative diseases that focus on amyloid-βclearance and gene therapy have not been successful.Some therapeutic applications focus on enhancing neuronal cell survival during the pathogenesis...Many approaches to neurodegenerative diseases that focus on amyloid-βclearance and gene therapy have not been successful.Some therapeutic applications focus on enhancing neuronal cell survival during the pathogenesis of neurodegenerative diseases,including mitochondrial dysfunction.Plasma membrane(PM)redox enzymes are crucial in maintaining cellular physiology and redox homeostasis in response to mitochondrial dysfunction.Neurohormetic phytochemicals are known to induce the expression of detoxifying enzymes under stress conditions.In this study,mechanisms of neuroprotective effects of 4-hydroxycinnamic acid(HCA)were examined by analyzing cell survival,levels of abnormal proteins,and mitochondrial functions in two different neuronal cells.HCA protected two neuronal cells exhibited high expression of PM redox enzymes and the consequent increase in the NAD^(+)/NADH ratio.Cells cultured with HCA showed delayed apoptosis and decreased oxidative/nitrative damage accompanied by decreased ROS production in the mitochondria.HCA increased the mitochondrial complexes I and II activities and ATP production.Also,HCA increased mitochondrial fusion and decreased mitochondrial fission.Overall,HCA maintains redox homeostasis and energy metabolism under oxidative/metabolic stress conditions.These findings suggest that HCA could be a promising therapeutic approach for neurodegenerative diseases.展开更多
基金Supported by the Program for New Century Excellent Talents in University(NCET-10-0176)the Natural Science Foundation of Jilin Province(No.20130521019JH)the fund of Jilin Provincial Education Department of China(No.2014154)
文摘Two new metal-organic complexes [Cd2(1,4-BDC)(4-pytyp)(H2O)4]·(1,4-BDC)(1) and [Cu2(1,4-BDC)(4-pytyp)2(H2O)2]·(1,4-BDC)·8H2O(2)(4-pytyp = 4'-(4''-pyridyl)-2,2':6',2''-terpyridine, 1,4-H2 BDC = 1,4-benzenedicarboxylic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis, infrared analysis and X-ray single-crystal diffraction. The scrutiny of single-crystal structure reveals that complex 1 forms to a 3D supramolecular network linked by π-π stacking interactions and hydrogen bonds. X-ray diffraction analysis reveals that complex 2 exhibits a 3D supramolecular network linked through complicated hydrogen bonds. The thermogravimetric analysis and photoluminescent properties of 1 and 2 are discussed in detail.
基金supported by the Science and Technology development plan of Jilin Province(2015052006JH)
文摘Two new complexes [Mn(DHTA)(PLQ)]n(1) and{[Co2(DHTA)(phen)2(H2 O)6]· DHTA}n(2)(H2 DHTA = 2,5-dihydroxy-1,4-benzenedicarboxylic acid, PLQ = 1,10-phenanthroline-5,6-quinone, phen = 1,10-phenanthroline) have been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, fluorescence spectrum, single-crystal and power X-ray diffraction. Complex 1 exhibits a two-dimensional(2 D) network, which was stabilized through O–H···O hydrogen bonding interactions. Complex 2 shows a zero-dimensional structure, which was further extended into a three-dimensional supramolecular structure through O–H···O hydrogen bonds and π-π interactions.
基金supported by the Science and Technology development plan of Jilin Province(2015052006JH)。
文摘A new complex[Mn(DHTA)(bipy)0.5]n(1,H2DHTA=2,5-dihydroxy-1,4-benzenedicarboxylic acid,bipy=2,2΄-bipyridine)was hydrothermally synthesized and structurally characterized by elemental analysis,IR spectrum,single-crystal and power X-ray diffraction.It belongs to monoclinic system,C2/c space group with a=12.874(13),b=11.302(12),c=17.352(18)Å,β=101.574(15)°,V=2474(4)Å3 and Z=4.It displays a one-dimensional zigzag chain-like structure,which was further extended into a three-dimensional supramolecular structure by hydrogen bonds andπ-πinteractions.Moreover,we analyzed Natural Bond Orbital(NBO)of 1 in using the PBE0/LANL2DZ method built in Gaussian 03 Program.The calculation results show the obvious covalent interaction between the coordinated atoms and Mn(Ⅱ)ion.
基金financially supported by the National Key Research and Development Program of China(2016YFB0301500)the National Natural Science Foundation of China(21878009)。
文摘The work herein employed a rotating packed bed(RPB)to intensify the sulfonation process of 1,4-diaminoanthraquinone leuco(DL)in an attempt to improve the yield of the product 1,4-diaminoanthra quinone-2-sulfonic acid(DSA).First,the effects of operating conditions in a stirred tank reactor(STR),including stirring speed,chlorosulfonic acid/DL molar ratio(η),solvent/DL mass ratio(ζ),reaction temperature and dropping speed of chlorosulfonic acid,on the yield of DSA were investigated.The yield of DSA can reach 87.34%under the optimal operating conditions:stirring speed of 500 r·min^(-1),ηof 4.5,ζof 7,reaction temperature of 150℃,dropping speed of 0.61 ml·min^(-1).In addition,the kinetics of the sulfonation process via the shrinking core model revealed that the reaction is controlled by diffusion via a product layer under the reaction temperature of 140℃.Furthermore,the RPB was employed to intensify the mass transfer between liquid and solid phases during the sulfonation reaction process.The results showed that the DSA yield of 92.69%obtained by RPB was 5.35%higher than that by STR,indicating that RPB can significantly intensify the mass transfer in the liquid-solid phase sulfonation reaction process.
基金supported by the Science and Technology Research Project of Henan Province (192102310490 and 212102310505)。
文摘The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl phosphate(TBP), di(2-ethylhexyl) phosphoric acid(D2EHPA) and TBP + D2EHPA dissolved in 1-octanol were investigated, respectively. The influences of the initial concentrations of TBP, D2EHPA and TBP + D2EHPA on distribution ratio(D) were discussed, as well as the reactive extraction mechanism were proposed. The obvious intensification effect was observed when the mixture of TBP and D2EHPA was used as extractant. The best extraction conditions were found to be of the molar ratio of D2EHPA and TBP at 2:1 and the equilibrium aqueous pH at 3.50-4.50. D values increased with the increase of the total concentration of TBP and D2EHPA in 1-octanol. Especially, the analysis on the extraction mechanisms clearly indicate(i) TBP in 1-octanol shows negligible reactive extraction toward 4-HP,(ii) D2EHPA in 1-octanol exhibits moderate extraction effect by forming 4-HP:D2EHPA(1:1) and 4-HP:2D2EHPA(1:2) type complexes, while(iii) D2EHPA in TBP/1-octanol demonstrates the maximum distribution ratio with the 4-HP:D2EHPA(1:1) type complex domination. The discussion provides new insights on the mechanism and opens a new way for the intensified extraction of amphoteric organic compounds by using the mixture of multiple extractants in the diluent.
文摘Activated carbons calcined at 400˚C and 600˚C (AC-400 and AC-600), prepared using palm nuts, collected in the town of Franceville in Gabon, were used to study the dynamic adsorption of MnO<sub>4</sub>-</sup> ions in acidic media on fixed bed column and on the kinetic modeling of experimental data of breakthrough curves of MnO<sub>4</sub>-</sup> ions obtained. Results on the adsorption of MnO<sub>4</sub>-</sup> ions in fixed-bed dynamics obtained on AC-400 and AC-600 adsorbents beds indicated that the AC-400 bed appears to be the most efficient in removing MnO<sub>4</sub>-</sup> ions in acidic media. Indeed, the adsorbed amounts, the adsorbed capacities at saturation and the elimination percentage of MnO<sub>4</sub>-</sup> ions obtained with AC-400 (31.24 mg;52.06 mg·g<sup>-1</sup> and 41.65% respectively) were higher compared to those obtained with AC-600 (9.87 mg;16.45 mg·g<sup>-1</sup> and 17.79% respectively). The breakthrough curves kinetic modeling revealed that the Thomas model and the pseudo-first-order kinetic model were the most suitable models to describe the adsorption of MnO<sub>4</sub>-</sup> ions on adsorbents studied in our experimental conditions. The results of the intraparticle diffusion model showed that intraparticle diffusion was involved in the adsorption mechanism of MnO<sub>4</sub>-</sup> ions on investigated adsorbents and was not the limiting step and the only process controlling MnO<sub>4</sub>-</sup> ions adsorption. In contrast to AC-400, the intraparticle diffusion on AC-600 bed plays an important role in the adsorption mechanism of MnO<sub>4</sub>-</sup> ions.
基金supported by the National Research Foundation of Korea(NRF)of the Korean Government(NRF-2021R1F1A1051212)by Logsynk Co.Ltd.(2-2021-1435-001).
文摘Many approaches to neurodegenerative diseases that focus on amyloid-βclearance and gene therapy have not been successful.Some therapeutic applications focus on enhancing neuronal cell survival during the pathogenesis of neurodegenerative diseases,including mitochondrial dysfunction.Plasma membrane(PM)redox enzymes are crucial in maintaining cellular physiology and redox homeostasis in response to mitochondrial dysfunction.Neurohormetic phytochemicals are known to induce the expression of detoxifying enzymes under stress conditions.In this study,mechanisms of neuroprotective effects of 4-hydroxycinnamic acid(HCA)were examined by analyzing cell survival,levels of abnormal proteins,and mitochondrial functions in two different neuronal cells.HCA protected two neuronal cells exhibited high expression of PM redox enzymes and the consequent increase in the NAD^(+)/NADH ratio.Cells cultured with HCA showed delayed apoptosis and decreased oxidative/nitrative damage accompanied by decreased ROS production in the mitochondria.HCA increased the mitochondrial complexes I and II activities and ATP production.Also,HCA increased mitochondrial fusion and decreased mitochondrial fission.Overall,HCA maintains redox homeostasis and energy metabolism under oxidative/metabolic stress conditions.These findings suggest that HCA could be a promising therapeutic approach for neurodegenerative diseases.