The formation of oligomeric hydrogen peroxide triggered by Criegee intermediate maybe contributes significantly to the formation and growth of secondary organic aerosol(SOA).However,to date,the reactivity of C2 Criege...The formation of oligomeric hydrogen peroxide triggered by Criegee intermediate maybe contributes significantly to the formation and growth of secondary organic aerosol(SOA).However,to date,the reactivity of C2 Criegee intermediates(CH_(3)CHOO)in areas contaminated with acidic gas remains poorly understood.Herein,high-level quantum chemical calculations and Born-Oppenheimer molecular dynamics(BOMD)simulations are used to explore the reaction of CH_(3)CHOO and H_(2)SO_(4)both in the gas phase and at the airwater interface.In the gas phase,the addition reaction of CH_(3)CHOO with H_(2)SO_(4)to generate CH_(3)HC(OOH)OSO_(3)H(HPES)is near-barrierless,regardless of the presence of water molecules.BOMD simulations showthat the reaction at the air-water interface is even faster than that in the gas phase.Further calculations reveal that the HPES has a tendency to aggregate with sulfuric acids,ammonias,and water molecules to form stable clusters,meanwhile the oligomerization reaction of CH_(3)CHOO with HPES in the gas phase is both thermochemically and kinetically favored.Also,it is noted that the interfacial HPES−ion can attract H_(2)SO_(4),NH_(3),(COOH)_(2)and HNO_(3)for particle formation from the gas phase to the water surface.Thus,the results of this work not only elucidate the high atmospheric reactivity of C2 Criegee intermediates in polluted regions,but also deepen our understanding of the formation process of atmospheric SOA induced by Criegee intermediates.展开更多
In situ electron paramagnetic resonance(EPR)monitoring of the photocatalytic halogen atom transfer(XAT)reaction with organic amines has provided insights into the dynamic transformations of intermediates,including cat...In situ electron paramagnetic resonance(EPR)monitoring of the photocatalytic halogen atom transfer(XAT)reaction with organic amines has provided insights into the dynamic transformations of intermediates,including catalyst intermediate states,amine alkyl radicals,and the dehalogenation of halogenated hydrocarbons to form carbon-centered radicals.This approach facilitated the photocatalytic single-linear state oxygen-promoted halogen atom transfer quinoxalinone alkylation reaction.展开更多
By manipulating the distribution of surface electrons,defect engineering enables effective control over the adsorption energy between adsorbates and active sites in the CO_(2)reduction reaction(CO_(2)RR).Herein,we rep...By manipulating the distribution of surface electrons,defect engineering enables effective control over the adsorption energy between adsorbates and active sites in the CO_(2)reduction reaction(CO_(2)RR).Herein,we report a hollow indium oxide nanotube containing both oxygen vacancy and sulfur doping(V_o-Sx-In_(2)O_(3))for improved CO_(2)-to-HCOOH electroreduction and Zn-CO_(2)battery.The componential synergy significantly reduces the*OCHO formation barrier to expedite protonation process and creates a favorable electronic micro-environment for*HCOOH desorption.As a result,the CO_(2)RR performance of Vo-Sx-In_(2)O_(3)outperforms Pure-In_(2)O_(3)and V_o-In_(2)O_(3),where V_o-S53-In_(2)O_(3)exhibits a maximal HCOOH Faradaic efficiency of 92.4%at-1,2 V vs.reversible hydrogen electrode(RHE)in H-cell and above 92%over a wide window potential with high current density(119.1 mA cm^(-2)at-1.1 V vs.RHE)in flow cell.Furthermore,the rechargeable Zn-CO_(2)battery utilizing V_o-S53-In_(2)O_(3)as cathode shows a high power density of 2.29 mW cm^(-2)and a long-term stability during charge-discharge cycles.This work provides a valuable perspective to elucidate co-defective catalysts in regulating the intermediates for efficient CO_(2)RR.展开更多
The enamines, iminium ions, and oxazolidinones are thought to be the key intermediates in the proline-catalyzed reactions of aldehydes or ketones, but there is an extensive contro- versy about their roles. Here, the c...The enamines, iminium ions, and oxazolidinones are thought to be the key intermediates in the proline-catalyzed reactions of aldehydes or ketones, but there is an extensive contro- versy about their roles. Here, the corresponding transition states connecting any two of the three kinds of species are located at the wB97XD/6-311++G** level of theory. The calcula- tions demonstrate that the oxazolidinones are the predominant species in both the gas phase and solvents; there exists tautomeric equilibrium among these species and the equilibriums are controlled by the employed solvents and temperature in the reaction. These results demonstrate that the concentration and role of the mentioned species are controlled by the employed solvent and temperature. A new reaction pathway is presented herein for the trans- formation between iminium ions and oxazolidinones through iminium ion-water complex and oxazolidinone-water complex. The calculations demonstrate that the rate-limiting step in proline-catalyzed Mannich reaction between acetaldehyde/keteones and N-Boc imines is the formation of the C-C bond rather than the intermediates tautomerization. These calculations rationalize the available experimental observations and can be valuable in optimizing the experimental conditions of asymmetric organic-catalyzed reactions of aldehydes or ketones.展开更多
Myelin,made by oligodendrocytes(OLs)in the central nervous system(CNS),is essential for neural transmission.In particular,myelin facilitates communication across the long connections between different brain regions th...Myelin,made by oligodendrocytes(OLs)in the central nervous system(CNS),is essential for neural transmission.In particular,myelin facilitates communication across the long connections between different brain regions that form the white matter.Myelinated segments also provide metabolic intermediates to axons,supporting their demanding energetic needs.Genetic disorders that disrupt myelin formation result in progressive neurologic degeneration.展开更多
The production of valuable chemicals using copper(Cu)catalysts via electrochemical CO or CO_(2)reduction reactions(CORR and CO_(2)RR)has shown great potential in the field of sustainable energy conversion[1].Previous ...The production of valuable chemicals using copper(Cu)catalysts via electrochemical CO or CO_(2)reduction reactions(CORR and CO_(2)RR)has shown great potential in the field of sustainable energy conversion[1].Previous research has primarily focused on analyzing the behavior of reaction intermediates or solely on the dynamics within the solution phase,while the synergistic effects between surface species and the solution,particularly the interfacial water and its non-covalent interactions with the Cu surface,have remained partially understood[2].展开更多
The development of bifunctional electrocatalysts capable of integrating biomass-derived platform molecule oxidation with organic reduction offers a promising strategy for simultaneously enhancing energy efficiency and...The development of bifunctional electrocatalysts capable of integrating biomass-derived platform molecule oxidation with organic reduction offers a promising strategy for simultaneously enhancing energy efficiency and generating high-value chemicals.However,designing catalysts that exhibit both high activity and stability in integrated systems remains a significant challenge.Herein,we report a selfsupported electrode composed of nitrogen-doped carbonized wood(NCW)supported NiCo nanosheets(NiCo_(0.3)/NCW)that enables the electrocatalytic 5-hydroxymethylfurfural oxidation to produce 2,5-furandicarboxylic acid(FDCA)and the nitrobenzene reduction to yield aniline in an integrated electrochemical cell.The NiCo_(0.3)/NCW electrode achieves the production of FDCA and aniline at a low cell voltage of 1.7 V,with~99%anodic and~92%cathodic Faradaic efficiencies,respectively.Experimental characterizations disclose that the hierarchical porous NCW architecture promotes the dispersion of active sites,while nitrogen doping strengthens metal-support interactions.In-situ spectroscopic experiments combined with density functional theory(DFT)calculations reveal that cobalt incorporation tunes the electronic structure of nickel,thus optimizing substrate and intermediate adsorption,and lowering energy barriers.These effects ultimately enhance the performance of the natural wood-derived catalyst in integrated biomass valorization and selective organic electrosynthesis.展开更多
Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2]....Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2].Toxic intermediates will be produced due to the dysfunction of biochemical pathways.The liver is responsible for many essential metabolic processes,therefore it becomes one of the most severely affected organ by metabolic diseases[3].Early onset of liver disorders in IEMs includes jaundice,hepatomegaly,splenomegaly,ascites,hepatic encephalopathy,and liver failure[4].In infants and young children under 3 years old with acute liver failure(ALF),IEMs account for 18.9%-43%[5].展开更多
Fabrication of large-area perovskite solar modules under ambient air conditions remains a critical challenge due to air sensitivity of perovskite intermediate phases during crystallization.Here,we introduce 2-iodoimid...Fabrication of large-area perovskite solar modules under ambient air conditions remains a critical challenge due to air sensitivity of perovskite intermediate phases during crystallization.Here,we introduce 2-iodoimidazole(IIZ)into the perovskite precursor,enabling the formation of an air-stable pureδ-phase intermediate,which,upon annealing,fully transforms into a highly orientedα-phase perovskite film with reduced defects and variability.Leveraging this approach,we achieve a stabilized power conversion efficiency of 20.9%for 927.5 cm^(2)perovskite solar modules with high reproducibility.The encapsulated modules meet stringent international photovoltaic testing standards(IEC61215:2021),demonstrating excellent stability under continuous operation,thermal cycling(-40 to 85℃)and damp heat(85℃ and 85%relative humidity).展开更多
文摘The photochemical[2+2]cycloaddition reaction of carbonyl compunds and alkenes was studied by photochemical induced dynamic nuclear spin polarization.
基金supported by the National Natural Science Foundation of China(Nos.22073059 and 22203052)the Natural Science Foundation of Shaanxi Province(No.2022JM-060)+1 种基金the Education Department of Shaanxi Provincial Government(No.23JC023)the Key Cultivation Project of Shaanxi University of Technology(No.SLG2101)。
文摘The formation of oligomeric hydrogen peroxide triggered by Criegee intermediate maybe contributes significantly to the formation and growth of secondary organic aerosol(SOA).However,to date,the reactivity of C2 Criegee intermediates(CH_(3)CHOO)in areas contaminated with acidic gas remains poorly understood.Herein,high-level quantum chemical calculations and Born-Oppenheimer molecular dynamics(BOMD)simulations are used to explore the reaction of CH_(3)CHOO and H_(2)SO_(4)both in the gas phase and at the airwater interface.In the gas phase,the addition reaction of CH_(3)CHOO with H_(2)SO_(4)to generate CH_(3)HC(OOH)OSO_(3)H(HPES)is near-barrierless,regardless of the presence of water molecules.BOMD simulations showthat the reaction at the air-water interface is even faster than that in the gas phase.Further calculations reveal that the HPES has a tendency to aggregate with sulfuric acids,ammonias,and water molecules to form stable clusters,meanwhile the oligomerization reaction of CH_(3)CHOO with HPES in the gas phase is both thermochemically and kinetically favored.Also,it is noted that the interfacial HPES−ion can attract H_(2)SO_(4),NH_(3),(COOH)_(2)and HNO_(3)for particle formation from the gas phase to the water surface.Thus,the results of this work not only elucidate the high atmospheric reactivity of C2 Criegee intermediates in polluted regions,but also deepen our understanding of the formation process of atmospheric SOA induced by Criegee intermediates.
基金Project supported by the Domestic Visiting Fellows Program of Hangzhou Normal University(No.4095C5022521106)。
文摘In situ electron paramagnetic resonance(EPR)monitoring of the photocatalytic halogen atom transfer(XAT)reaction with organic amines has provided insights into the dynamic transformations of intermediates,including catalyst intermediate states,amine alkyl radicals,and the dehalogenation of halogenated hydrocarbons to form carbon-centered radicals.This approach facilitated the photocatalytic single-linear state oxygen-promoted halogen atom transfer quinoxalinone alkylation reaction.
基金supported by the Fundamental Research Funds for the Central Universities(22120230104).
文摘By manipulating the distribution of surface electrons,defect engineering enables effective control over the adsorption energy between adsorbates and active sites in the CO_(2)reduction reaction(CO_(2)RR).Herein,we report a hollow indium oxide nanotube containing both oxygen vacancy and sulfur doping(V_o-Sx-In_(2)O_(3))for improved CO_(2)-to-HCOOH electroreduction and Zn-CO_(2)battery.The componential synergy significantly reduces the*OCHO formation barrier to expedite protonation process and creates a favorable electronic micro-environment for*HCOOH desorption.As a result,the CO_(2)RR performance of Vo-Sx-In_(2)O_(3)outperforms Pure-In_(2)O_(3)and V_o-In_(2)O_(3),where V_o-S53-In_(2)O_(3)exhibits a maximal HCOOH Faradaic efficiency of 92.4%at-1,2 V vs.reversible hydrogen electrode(RHE)in H-cell and above 92%over a wide window potential with high current density(119.1 mA cm^(-2)at-1.1 V vs.RHE)in flow cell.Furthermore,the rechargeable Zn-CO_(2)battery utilizing V_o-S53-In_(2)O_(3)as cathode shows a high power density of 2.29 mW cm^(-2)and a long-term stability during charge-discharge cycles.This work provides a valuable perspective to elucidate co-defective catalysts in regulating the intermediates for efficient CO_(2)RR.
文摘The enamines, iminium ions, and oxazolidinones are thought to be the key intermediates in the proline-catalyzed reactions of aldehydes or ketones, but there is an extensive contro- versy about their roles. Here, the corresponding transition states connecting any two of the three kinds of species are located at the wB97XD/6-311++G** level of theory. The calcula- tions demonstrate that the oxazolidinones are the predominant species in both the gas phase and solvents; there exists tautomeric equilibrium among these species and the equilibriums are controlled by the employed solvents and temperature in the reaction. These results demonstrate that the concentration and role of the mentioned species are controlled by the employed solvent and temperature. A new reaction pathway is presented herein for the trans- formation between iminium ions and oxazolidinones through iminium ion-water complex and oxazolidinone-water complex. The calculations demonstrate that the rate-limiting step in proline-catalyzed Mannich reaction between acetaldehyde/keteones and N-Boc imines is the formation of the C-C bond rather than the intermediates tautomerization. These calculations rationalize the available experimental observations and can be valuable in optimizing the experimental conditions of asymmetric organic-catalyzed reactions of aldehydes or ketones.
基金support held by JPA,Collaborative Network Award BRAVEinMS,Grant/Award Number:PA-1604-08492(MG)from the Multiple Sclerosis Society of Canada,Grant/Award Number:1038154(to TEK).
文摘Myelin,made by oligodendrocytes(OLs)in the central nervous system(CNS),is essential for neural transmission.In particular,myelin facilitates communication across the long connections between different brain regions that form the white matter.Myelinated segments also provide metabolic intermediates to axons,supporting their demanding energetic needs.Genetic disorders that disrupt myelin formation result in progressive neurologic degeneration.
文摘The production of valuable chemicals using copper(Cu)catalysts via electrochemical CO or CO_(2)reduction reactions(CORR and CO_(2)RR)has shown great potential in the field of sustainable energy conversion[1].Previous research has primarily focused on analyzing the behavior of reaction intermediates or solely on the dynamics within the solution phase,while the synergistic effects between surface species and the solution,particularly the interfacial water and its non-covalent interactions with the Cu surface,have remained partially understood[2].
基金financially supported by the National Natural Science Foundation of China(22504118,T2293692,22525042 and 22373080)the Natural Science Foundation of Fujian Province of China(2025J08010)+3 种基金the Natural Science Foundation of Xiamen,China(3502Z202471009 and 3502Z202472001)funding support from the Fundamental Research Funds for the Central Universities(20720240054)the Nan-qiang Youth Scholar Program of Xiamen Universitythe Xiaomi Young Talents Program/Xiaomi Foundation。
文摘The development of bifunctional electrocatalysts capable of integrating biomass-derived platform molecule oxidation with organic reduction offers a promising strategy for simultaneously enhancing energy efficiency and generating high-value chemicals.However,designing catalysts that exhibit both high activity and stability in integrated systems remains a significant challenge.Herein,we report a selfsupported electrode composed of nitrogen-doped carbonized wood(NCW)supported NiCo nanosheets(NiCo_(0.3)/NCW)that enables the electrocatalytic 5-hydroxymethylfurfural oxidation to produce 2,5-furandicarboxylic acid(FDCA)and the nitrobenzene reduction to yield aniline in an integrated electrochemical cell.The NiCo_(0.3)/NCW electrode achieves the production of FDCA and aniline at a low cell voltage of 1.7 V,with~99%anodic and~92%cathodic Faradaic efficiencies,respectively.Experimental characterizations disclose that the hierarchical porous NCW architecture promotes the dispersion of active sites,while nitrogen doping strengthens metal-support interactions.In-situ spectroscopic experiments combined with density functional theory(DFT)calculations reveal that cobalt incorporation tunes the electronic structure of nickel,thus optimizing substrate and intermediate adsorption,and lowering energy barriers.These effects ultimately enhance the performance of the natural wood-derived catalyst in integrated biomass valorization and selective organic electrosynthesis.
文摘Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2].Toxic intermediates will be produced due to the dysfunction of biochemical pathways.The liver is responsible for many essential metabolic processes,therefore it becomes one of the most severely affected organ by metabolic diseases[3].Early onset of liver disorders in IEMs includes jaundice,hepatomegaly,splenomegaly,ascites,hepatic encephalopathy,and liver failure[4].In infants and young children under 3 years old with acute liver failure(ALF),IEMs account for 18.9%-43%[5].
基金supported by the National Key R&D Program of China(2023YFB4204504)National Science Fund for Dis-tinguished Young Scholars(T2325016)+7 种基金National Natural Science Foundation of China(U21A2076)Natural Science Foundation of Jiangsu Province(BK20232022,BE2022021 and BE2022026)Fundamental Research Funds for the Central Universities(0213/14380206 and 0205/14380252)Frontiers Science Center for Critical Earth Material Cycling Fund(DLTD2109 and 2024ZD06)Program for Innovative Talents and Entrepreneur in JiangsuChina Postdoctoral Science Foundation(2023M731579)Jiangsu Funding Program for Excellent Postdoctoral Talent(2023ZB348)Postdoctoral Innovative Talents Support Project from the China Postdoctoral Science Foundation(BX20230157)。
文摘Fabrication of large-area perovskite solar modules under ambient air conditions remains a critical challenge due to air sensitivity of perovskite intermediate phases during crystallization.Here,we introduce 2-iodoimidazole(IIZ)into the perovskite precursor,enabling the formation of an air-stable pureδ-phase intermediate,which,upon annealing,fully transforms into a highly orientedα-phase perovskite film with reduced defects and variability.Leveraging this approach,we achieve a stabilized power conversion efficiency of 20.9%for 927.5 cm^(2)perovskite solar modules with high reproducibility.The encapsulated modules meet stringent international photovoltaic testing standards(IEC61215:2021),demonstrating excellent stability under continuous operation,thermal cycling(-40 to 85℃)and damp heat(85℃ and 85%relative humidity).