Objective:The neurotoxicity of carbon monoxide(CO)to the central nervous system is a key pathogenesis of delayed encephalopathy after acute carbon monoxide poisoning(DEACMP).Our previous study found that retinoic acid...Objective:The neurotoxicity of carbon monoxide(CO)to the central nervous system is a key pathogenesis of delayed encephalopathy after acute carbon monoxide poisoning(DEACMP).Our previous study found that retinoic acid(RA)can suppress the neurotoxic effects of CO.This study further explores,in vivo and in vitro,the molecular mechanisms by which RA alleviates CO-induced central nervous system damage.Methods:A cytotoxic model was established using the mouse hippocampal neuronal cell line HT22 and primary oligodendrocytes exposed to CO,and a DEACMP animal model was established in adult Kunming mice.Cell viability and apoptosis of hippocampal neurons and oligodendrocytes were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay and Annexin V/propidium iodide(PI)double staining.The transcriptional and protein expression of each gene was detected using real time fluorescence quantitative PCR(RT-qPCR)and Western blotting.Long noncoding RNA(lncRNA)SNHG15 and LINGO-1 were knocked down or overexpressed to observe changes in neurons and oligodendrocytes.In DEACMP mice,SNHG15 or LINGO-1 were knocked down to assess changes in central nervous tissue and downstream protein expression.Results:RA at 10 and 20μmol/L significantly reversed CO-induced apoptosis of hippocampal neurons and oligodendrocytes,downregulation of SNHG15 and LINGO-1,and upregulation of brain-derived neurotrophic factor(BDNF)and tyrosine kinase receptor B(TrkB)(all P<0.05).Overexpression of SNHG15 or LINGO-1 weakened the protective effect of RA against CO-induced cytotoxicity(all P<0.05).Knockdown of SNHG15 or LINGO-1 alleviated CO-induced apoptosis of hippocampal neurons and oligodendrocytes and upregulated BDNF and TrkB expression levels(all P<0.05).Experiments in DEACMP model mice showed that knockdown of SNHG15 or LINGO-1 mitigated central nervous system injury in DEACMP(all P<0.05).Conclusion:RA alleviates CO-induced apoptosis of hippocampal neurons and oligodendrocytes,thereby reducing central nervous system injury and exerting neuroprotective effects.LncRNA SNHG15 and LINGO-1 are key molecules mediating RA induced inhibition of neuronal apoptosis and are associated with the BDNF/TrkB pathway.These findings provide a theoretical framework for optimizing the clinical treatment of DEACMP and lay an experimental foundation for elucidating its molecular mechanisms.展开更多
In order to decrease the solubility of PbSO4 and enhance lead recovery from PbSO4 bearing wastes, CO was employed as a reductant to transform PbSO4 into Pb S. Reaction system was established and reductive thermodynami...In order to decrease the solubility of PbSO4 and enhance lead recovery from PbSO4 bearing wastes, CO was employed as a reductant to transform PbSO4 into Pb S. Reaction system was established and reductive thermodynamics of PbSO4 was calculated by software HSC 5.0. The effects of gas concentration, reaction temperature, time and mass of sample on reduction of PbSO4 were examined by thermogravimetry(TG) and XRD. Roasting tests further verify the conclusions of thermodynamic and TG analyses. The results show that increasing temperature in the reasonable range and CO content are favorable for the formation of Pb S. The reduction process is controlled by chemical reaction and calculation value of the activation energy is 47.88 k J/mol.展开更多
The dissolved gas analysis is one of the most effective and convenient methods to diagnose the early discharge faults of transformers,the fault involves the solid insulation.oil—paper insulation cracks and releases c...The dissolved gas analysis is one of the most effective and convenient methods to diagnose the early discharge faults of transformers,the fault involves the solid insulation.oil—paper insulation cracks and releases carbon monoxide(co)gas.Therefore,the detection of CO can forecast the potentia1 inner faults of oil.filled transformers.展开更多
This study systematically investigated the effects of experimental conditions,crystal phase,and microstructure on the preparation of V_(2)O_(3)for vanadium flow batteries by reducing ammonium metavanadate extracted fr...This study systematically investigated the effects of experimental conditions,crystal phase,and microstructure on the preparation of V_(2)O_(3)for vanadium flow batteries by reducing ammonium metavanadate extracted from waste catalyst.The optimized experimental conditions were determined as follows:the CO reduction temperature was set at 575℃,the reduction time was 1 hour,the CO flow rate was 50 mL/min,and furnace cooling was performed subsequently.Under these conditions,the samples obtained were predominantly composed of single-phase V_(2)O_(3).Microstructural analysis reveals tightly packed grain configurations exhibiting flake-like or block-like morphologies.Significantly,the as-synthesized V_(2)O_(3)demonstrates sufficient purity for fabricating high-performance electrolytes in all-vanadium flow batteries,showing promising electrochemical applicability.展开更多
The effect of H_2 gas content on the reduction of Panzhihua titanomagnetite concentrate pellets by carbon monoxide was investigated by isothermal reduction experiment using CO-N_2-H_2 gas mixtures in a vertical electr...The effect of H_2 gas content on the reduction of Panzhihua titanomagnetite concentrate pellets by carbon monoxide was investigated by isothermal reduction experiment using CO-N_2-H_2 gas mixtures in a vertical electric resistance furnace.The morphology and phase transformation of reduced samples obtained were detected by scanning electron microscopy,energy disperse spectroscopy analysis and X-ray diffractometry respectively.The results show that increasing H_2 content will enhance the initial stage of reduction rate apparently.There are two reasons responsible for this effect,one is that H_2 accelerates the chemical reaction,and the other is that the addition of H_2 gas can improve the porosity of pellet intensively.It is noteworthy that this effect is more obvious when the reduction temperature reaches 1473 K with sticking phenomenon happening.There are no crystalline phases which can be found such as ulvospinle,ilmenite,ferrous-pseudobrookite and any titanium oxide except titanomagnetite(TTM).The reduction progress is suggested as follows:1) Fe_2O_3→Fe_3O_4→FeO→Fe;2) Fe_2TiO_5→Fe_2TiO_4+Fe_3O_4→TTM.Element Al migrates and gets enriched in high titanium content iron ores,and eventually Al to Ti molar ratio is 1:3.Al is likely to dissolve in titanium iron oxides to form a kind of composite iron compound,which results in the restrain of reduction.展开更多
Heme oxygenase(HO)is the enzyme that catalyzes the degradation of heme and leads to the formation of carbon monoxide,free iron and biliverdin.Emerging evidence suggests that HO-1,an inducible isoform of HO,can exert v...Heme oxygenase(HO)is the enzyme that catalyzes the degradation of heme and leads to the formation of carbon monoxide,free iron and biliverdin.Emerging evidence suggests that HO-1,an inducible isoform of HO,can exert vaso-protective effects.However,such vascular benefit展开更多
For developing TiO based imitated gold materials, the wettabilities of Fe and Fe Cr Ni Ti on TiO were studied. The results indicated that the wettabilities of Fe and Fe Cr on TiO were poor, and their wetting angles we...For developing TiO based imitated gold materials, the wettabilities of Fe and Fe Cr Ni Ti on TiO were studied. The results indicated that the wettabilities of Fe and Fe Cr on TiO were poor, and their wetting angles were about 90° at melting point. The wetting angles reduced with the increase of wetting temperature, but the influence of temperature was small. Fe and Fe Cr containing Cr 50% or less could react with TiO on the interface to form Fe 2Ti and Ti 2O 3, but this did not improve the wettability effectively. When Ni Ti was added into Fe Cr alloy, Ni 3Ti was formed on the interface, which can reduce the interface energy, improve the wettability, and prevent the formation of Fe 2Ti and Ti 2O 3. The wetting angles could go down to about 40° when 3% Ni Ti was added to Fe Cr alloy.展开更多
Exploring catalysts with high catalytic activity and low cost is crucial for promoting the electrocatalytic reduction of CO_(2).In this study,Ag nanoparticle catalysts were synthesized on GS carbon and vapor grown car...Exploring catalysts with high catalytic activity and low cost is crucial for promoting the electrocatalytic reduction of CO_(2).In this study,Ag nanoparticle catalysts were synthesized on GS carbon and vapor grown carbon fiber(VGCF)carbon carriers using different silver precursors(AgAc,AgNO_(3))through the ultrafast high temperature thermal shock method.The experimental results demonstrated that the performance of Ag catalysts for the electrocatalytic reduction of CO_(2) to CO could be significantly enhanced by modulating the nanostructure,carrier,and metal loading.The VGCF-AgNO_(3)-HT nanoparticles exhibited a relatively regular spherical morphology,with smaller particle sizes and uniform distribution.Furthermore,the intricate and overlapping arrangement of VGCF carbon nanofibers contributed to increasing the active area for electrochemical reactions,making it an excellent catalyst carrier.Catalysts with varying Ag loadings were prepared using the thermal shock method,and it was observed that the nanoparticles maintained their superior nanostructures even with increased Ag loading.The Ag-HT-65 catalyst exhibited outstanding catalytic performance,achieving a CO Faradaic efficiency of 93.03% at a potential of−0.8 V(vs.RHE).After 12 h of testing,the CO Faradaic efficiency remained 90%,exhibiting an excellent stability.展开更多
Hydroformylation of olefins catalyzed by heteronuclear metal cluster [PhCH<sub>2</sub>Me<sub>3</sub>N]-[FeCo<sub>3</sub>（CO）<sub>12</sub>] was studied. The effect of t...Hydroformylation of olefins catalyzed by heteronuclear metal cluster [PhCH<sub>2</sub>Me<sub>3</sub>N]-[FeCo<sub>3</sub>（CO）<sub>12</sub>] was studied. The effect of temperature, pressure, and solvent ect. on olefin hydroformylation was examined. The results show that for the hydroformylation of various olefins, e.g. 1-hexene, isobutene, 2-octene, cyclohexene, diisobutene, and styrene, the Fe-Co cluster exhibits rather high activity under mild conditions. For example, under the pressure such of 4 MPa, H<sub>2</sub>/CO ratio of 1: 1, at 120℃, 1-hexene was hydroformylated to heptanal with the conversion of 】 80％ and the selectivity of 】 95％ in 1 hr.展开更多
The hydroformylation of hexene-1 catalyzed by Rh<sub>4</sub> （CO）<sub>1</sub>2 and 〔Rh（CO）<sub>2</sub>Cl〕<sub>2</sub> andthe effects of solvents （benzene, n-hepta...The hydroformylation of hexene-1 catalyzed by Rh<sub>4</sub> （CO）<sub>1</sub>2 and 〔Rh（CO）<sub>2</sub>Cl〕<sub>2</sub> andthe effects of solvents （benzene, n-heptane and THF） and PPh<sub>3</sub> on the activity andselectivity of the catalysts were studied.The results indicated that the activity of Rh<sub>4</sub>（CO）<sub>12</sub> decreased with increasing solventpolarity and it did not change appreciably with addition of PPh<sub>3</sub> when the molar ratioPPh<sub>3</sub>/Rh<sub>4</sub>（CO）<sub>12</sub>≤4. Thc activity of Rh<sub>4</sub>（CO）<sub>12</sub> was over twice as large as that of〔Rh（CO）<sub>2</sub>Cl〕<sub>2</sub> when calculated according to the number of moles of rhodium clusters inbenzene without PPh<sub>3</sub>, but the activities of both Rh<sub>4</sub>（CO）<sub>12</sub> and 〔Rh（CO）<sub>2</sub>Cl〕<sub>2</sub> wereabout the same when calculated according to the number of rhodium atoms. It is suggestedthat the clusters probably dissociated into the similar active rhodium mononuclear speciesunder the reaction conditions and the species formed a cluster similar to Rh<sub>4</sub>（CO）<sub>12</sub> againwhen the conditions were reduced to the ambient temperature and pressure.展开更多
Reaction kinetics of CO<sub>2</sub>（CO）<sub>8</sub>-catalyzed carbonylation of benzyl chloride was studied in a liquid-liquid two-phase system（water/p-xylene）. The disappearance rate of ben...Reaction kinetics of CO<sub>2</sub>（CO）<sub>8</sub>-catalyzed carbonylation of benzyl chloride was studied in a liquid-liquid two-phase system（water/p-xylene）. The disappearance rate of benzyl chloride is found to fit a pseudo first order kinetics law when the carbon monoxide pressure is kept constant. The observed rate constant is directly proportional to the amount of Co<sub>2</sub>（CO）<sub>8</sub>, PhCH<sub>2</sub>N<sup>+</sup>（CH<sub>3</sub>）<sub>3</sub>Cl<sup>-</sup> and NaOH. It is shown that the rate-limiting step is the cleavage of the acylcobalt carbonyl [PhCH<sub>2</sub>COCo（CO）<sub>4</sub>] by PhCH<sub>2</sub>N<sup>+</sup>（CH<sub>3</sub>）<sub>3</sub>OH<sup>-</sup> at the liquid-liquid interface. According to the experimental kinetic results, the reaction mechanism is suggested and the reaction rate equation is derived.展开更多
基金supported by the Natural Science Foundation of Hunan Province(2021JJ31089)the Scientific Research Project of Health Commission of Hunan Province(202203104548),China。
文摘Objective:The neurotoxicity of carbon monoxide(CO)to the central nervous system is a key pathogenesis of delayed encephalopathy after acute carbon monoxide poisoning(DEACMP).Our previous study found that retinoic acid(RA)can suppress the neurotoxic effects of CO.This study further explores,in vivo and in vitro,the molecular mechanisms by which RA alleviates CO-induced central nervous system damage.Methods:A cytotoxic model was established using the mouse hippocampal neuronal cell line HT22 and primary oligodendrocytes exposed to CO,and a DEACMP animal model was established in adult Kunming mice.Cell viability and apoptosis of hippocampal neurons and oligodendrocytes were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay and Annexin V/propidium iodide(PI)double staining.The transcriptional and protein expression of each gene was detected using real time fluorescence quantitative PCR(RT-qPCR)and Western blotting.Long noncoding RNA(lncRNA)SNHG15 and LINGO-1 were knocked down or overexpressed to observe changes in neurons and oligodendrocytes.In DEACMP mice,SNHG15 or LINGO-1 were knocked down to assess changes in central nervous tissue and downstream protein expression.Results:RA at 10 and 20μmol/L significantly reversed CO-induced apoptosis of hippocampal neurons and oligodendrocytes,downregulation of SNHG15 and LINGO-1,and upregulation of brain-derived neurotrophic factor(BDNF)and tyrosine kinase receptor B(TrkB)(all P<0.05).Overexpression of SNHG15 or LINGO-1 weakened the protective effect of RA against CO-induced cytotoxicity(all P<0.05).Knockdown of SNHG15 or LINGO-1 alleviated CO-induced apoptosis of hippocampal neurons and oligodendrocytes and upregulated BDNF and TrkB expression levels(all P<0.05).Experiments in DEACMP model mice showed that knockdown of SNHG15 or LINGO-1 mitigated central nervous system injury in DEACMP(all P<0.05).Conclusion:RA alleviates CO-induced apoptosis of hippocampal neurons and oligodendrocytes,thereby reducing central nervous system injury and exerting neuroprotective effects.LncRNA SNHG15 and LINGO-1 are key molecules mediating RA induced inhibition of neuronal apoptosis and are associated with the BDNF/TrkB pathway.These findings provide a theoretical framework for optimizing the clinical treatment of DEACMP and lay an experimental foundation for elucidating its molecular mechanisms.
基金Project(51204210)supported by the National Natural Science Foundation of ChinaProject(2011AA061001)supported by the National High Technology Research and Development Program of ChinaProject(2012BAC12B04)supported by the National Science and Technology Pillar Program during the Twelfth Five-Year Plan of China
文摘In order to decrease the solubility of PbSO4 and enhance lead recovery from PbSO4 bearing wastes, CO was employed as a reductant to transform PbSO4 into Pb S. Reaction system was established and reductive thermodynamics of PbSO4 was calculated by software HSC 5.0. The effects of gas concentration, reaction temperature, time and mass of sample on reduction of PbSO4 were examined by thermogravimetry(TG) and XRD. Roasting tests further verify the conclusions of thermodynamic and TG analyses. The results show that increasing temperature in the reasonable range and CO content are favorable for the formation of Pb S. The reduction process is controlled by chemical reaction and calculation value of the activation energy is 47.88 k J/mol.
文摘The dissolved gas analysis is one of the most effective and convenient methods to diagnose the early discharge faults of transformers,the fault involves the solid insulation.oil—paper insulation cracks and releases carbon monoxide(co)gas.Therefore,the detection of CO can forecast the potentia1 inner faults of oil.filled transformers.
文摘This study systematically investigated the effects of experimental conditions,crystal phase,and microstructure on the preparation of V_(2)O_(3)for vanadium flow batteries by reducing ammonium metavanadate extracted from waste catalyst.The optimized experimental conditions were determined as follows:the CO reduction temperature was set at 575℃,the reduction time was 1 hour,the CO flow rate was 50 mL/min,and furnace cooling was performed subsequently.Under these conditions,the samples obtained were predominantly composed of single-phase V_(2)O_(3).Microstructural analysis reveals tightly packed grain configurations exhibiting flake-like or block-like morphologies.Significantly,the as-synthesized V_(2)O_(3)demonstrates sufficient purity for fabricating high-performance electrolytes in all-vanadium flow batteries,showing promising electrochemical applicability.
基金Project (51134008) supported by the National Natural Science Foundation of ChinaProject (2012CB720401) supported by the National Basic Research Program of China
文摘The effect of H_2 gas content on the reduction of Panzhihua titanomagnetite concentrate pellets by carbon monoxide was investigated by isothermal reduction experiment using CO-N_2-H_2 gas mixtures in a vertical electric resistance furnace.The morphology and phase transformation of reduced samples obtained were detected by scanning electron microscopy,energy disperse spectroscopy analysis and X-ray diffractometry respectively.The results show that increasing H_2 content will enhance the initial stage of reduction rate apparently.There are two reasons responsible for this effect,one is that H_2 accelerates the chemical reaction,and the other is that the addition of H_2 gas can improve the porosity of pellet intensively.It is noteworthy that this effect is more obvious when the reduction temperature reaches 1473 K with sticking phenomenon happening.There are no crystalline phases which can be found such as ulvospinle,ilmenite,ferrous-pseudobrookite and any titanium oxide except titanomagnetite(TTM).The reduction progress is suggested as follows:1) Fe_2O_3→Fe_3O_4→FeO→Fe;2) Fe_2TiO_5→Fe_2TiO_4+Fe_3O_4→TTM.Element Al migrates and gets enriched in high titanium content iron ores,and eventually Al to Ti molar ratio is 1:3.Al is likely to dissolve in titanium iron oxides to form a kind of composite iron compound,which results in the restrain of reduction.
文摘Heme oxygenase(HO)is the enzyme that catalyzes the degradation of heme and leads to the formation of carbon monoxide,free iron and biliverdin.Emerging evidence suggests that HO-1,an inducible isoform of HO,can exert vaso-protective effects.However,such vascular benefit
文摘For developing TiO based imitated gold materials, the wettabilities of Fe and Fe Cr Ni Ti on TiO were studied. The results indicated that the wettabilities of Fe and Fe Cr on TiO were poor, and their wetting angles were about 90° at melting point. The wetting angles reduced with the increase of wetting temperature, but the influence of temperature was small. Fe and Fe Cr containing Cr 50% or less could react with TiO on the interface to form Fe 2Ti and Ti 2O 3, but this did not improve the wettability effectively. When Ni Ti was added into Fe Cr alloy, Ni 3Ti was formed on the interface, which can reduce the interface energy, improve the wettability, and prevent the formation of Fe 2Ti and Ti 2O 3. The wetting angles could go down to about 40° when 3% Ni Ti was added to Fe Cr alloy.
基金Project(52304338)supported by the National Natural Science Foundation of China。
文摘Exploring catalysts with high catalytic activity and low cost is crucial for promoting the electrocatalytic reduction of CO_(2).In this study,Ag nanoparticle catalysts were synthesized on GS carbon and vapor grown carbon fiber(VGCF)carbon carriers using different silver precursors(AgAc,AgNO_(3))through the ultrafast high temperature thermal shock method.The experimental results demonstrated that the performance of Ag catalysts for the electrocatalytic reduction of CO_(2) to CO could be significantly enhanced by modulating the nanostructure,carrier,and metal loading.The VGCF-AgNO_(3)-HT nanoparticles exhibited a relatively regular spherical morphology,with smaller particle sizes and uniform distribution.Furthermore,the intricate and overlapping arrangement of VGCF carbon nanofibers contributed to increasing the active area for electrochemical reactions,making it an excellent catalyst carrier.Catalysts with varying Ag loadings were prepared using the thermal shock method,and it was observed that the nanoparticles maintained their superior nanostructures even with increased Ag loading.The Ag-HT-65 catalyst exhibited outstanding catalytic performance,achieving a CO Faradaic efficiency of 93.03% at a potential of−0.8 V(vs.RHE).After 12 h of testing,the CO Faradaic efficiency remained 90%,exhibiting an excellent stability.
基金This work was supported by National Natural Science Foundation of China.
文摘Hydroformylation of olefins catalyzed by heteronuclear metal cluster [PhCH<sub>2</sub>Me<sub>3</sub>N]-[FeCo<sub>3</sub>（CO）<sub>12</sub>] was studied. The effect of temperature, pressure, and solvent ect. on olefin hydroformylation was examined. The results show that for the hydroformylation of various olefins, e.g. 1-hexene, isobutene, 2-octene, cyclohexene, diisobutene, and styrene, the Fe-Co cluster exhibits rather high activity under mild conditions. For example, under the pressure such of 4 MPa, H<sub>2</sub>/CO ratio of 1: 1, at 120℃, 1-hexene was hydroformylated to heptanal with the conversion of 】 80％ and the selectivity of 】 95％ in 1 hr.
基金This work was supported by the Science Foundation of Chinese Academy of Sciences
文摘The hydroformylation of hexene-1 catalyzed by Rh<sub>4</sub> （CO）<sub>1</sub>2 and 〔Rh（CO）<sub>2</sub>Cl〕<sub>2</sub> andthe effects of solvents （benzene, n-heptane and THF） and PPh<sub>3</sub> on the activity andselectivity of the catalysts were studied.The results indicated that the activity of Rh<sub>4</sub>（CO）<sub>12</sub> decreased with increasing solventpolarity and it did not change appreciably with addition of PPh<sub>3</sub> when the molar ratioPPh<sub>3</sub>/Rh<sub>4</sub>（CO）<sub>12</sub>≤4. Thc activity of Rh<sub>4</sub>（CO）<sub>12</sub> was over twice as large as that of〔Rh（CO）<sub>2</sub>Cl〕<sub>2</sub> when calculated according to the number of moles of rhodium clusters inbenzene without PPh<sub>3</sub>, but the activities of both Rh<sub>4</sub>（CO）<sub>12</sub> and 〔Rh（CO）<sub>2</sub>Cl〕<sub>2</sub> wereabout the same when calculated according to the number of rhodium atoms. It is suggestedthat the clusters probably dissociated into the similar active rhodium mononuclear speciesunder the reaction conditions and the species formed a cluster similar to Rh<sub>4</sub>（CO）<sub>12</sub> againwhen the conditions were reduced to the ambient temperature and pressure.
文摘Reaction kinetics of CO<sub>2</sub>（CO）<sub>8</sub>-catalyzed carbonylation of benzyl chloride was studied in a liquid-liquid two-phase system（water/p-xylene）. The disappearance rate of benzyl chloride is found to fit a pseudo first order kinetics law when the carbon monoxide pressure is kept constant. The observed rate constant is directly proportional to the amount of Co<sub>2</sub>（CO）<sub>8</sub>, PhCH<sub>2</sub>N<sup>+</sup>（CH<sub>3</sub>）<sub>3</sub>Cl<sup>-</sup> and NaOH. It is shown that the rate-limiting step is the cleavage of the acylcobalt carbonyl [PhCH<sub>2</sub>COCo（CO）<sub>4</sub>] by PhCH<sub>2</sub>N<sup>+</sup>（CH<sub>3</sub>）<sub>3</sub>OH<sup>-</sup> at the liquid-liquid interface. According to the experimental kinetic results, the reaction mechanism is suggested and the reaction rate equation is derived.
