Osteoporosis is characterized by a decrease in bone mass and strength, rendering people prone to osteoporotic fractures caused by low-energy forces. The primary treatment strategy for osteoporotic fractures is surgery...Osteoporosis is characterized by a decrease in bone mass and strength, rendering people prone to osteoporotic fractures caused by low-energy forces. The primary treatment strategy for osteoporotic fractures is surgery;however, the compromised and comminuted bones in osteoporotic fracture sites are not conducive to optimum reduction and rigid fixation. In addition, these patients always exhibit accompanying aging-related disorders, including high inflammatory status, decreased mechanical loading and abnormal skeletal metabolism, which are disadvantages for fracture healing around sites that have undergone orthopedic procedures. Since the incidence of osteoporosis is expected to increase worldwide, orthopedic surgeons should pay more attention to comprehensive strategies for improving the poor prognosis of osteoporotic fractures. Herein, we highlight the molecular basis of osteoimmunology and bone mechanosensation in different healing phases of elderly osteoporotic fractures, guiding perioperative management to alleviate the unfavorable effects of insufficient mechanical loading, high inflammatory levels and pathogen infection. The well-informed pharmacologic and surgical intervention, including treatment with anti-inflammatory drugs and sufficient application of antibiotics, as well as bench-to-bedside strategies for bone augmentation and hardware selection, should be made according to a comprehensive understanding of bone biomechanical properties in addition to the remodeling status of osteoporotic bones, which is necessary for creating proper biological and mechanical environments for bone union and remodeling. Multidisciplinary collaboration will facilitate the improvement of overall osteoporotic care and reduction of secondary fracture incidence.展开更多
In the course of vehicle license plate （VLP） automatic recognition, tilt correction is a very crucial process. According to Karhunen-Loeve （K-L） transformation, the coordinates of characters in the image are arran...In the course of vehicle license plate （VLP） automatic recognition, tilt correction is a very crucial process. According to Karhunen-Loeve （K-L） transformation, the coordinates of characters in the image are arranged into a two-dimensional covariance matrix, on the basis of which the centered process is carried out. Then, the eigenvector and the rotation angle α are computed in turn. The whole image is rotated by -α. Thus, image horizontal tilt correction is performed. In the vertical tilt correction process, three correction methods, which are K-L transformation method, the line fitting method based on K -means clustering （LFMBKC）, and the line fitting based on least squares （LFMBLS）, are put forward to compute the vertical tilt angle θ. After shear transformation （ST） is imposed on the rotated image, the final correction image is obtained. The experimental results verify that this proposed method can be easily implemented, and can quickly and accurately get the tilt angle. It provides a new effective way for the VLP image tilt correction as well.展开更多
Cross-correlating the data on neutral hydrogen(HⅠ)21 cm intensity mapping with galaxy surveys is an effective method to extract astrophysical and cosmological information.In this work,we investigate the cross-correla...Cross-correlating the data on neutral hydrogen(HⅠ)21 cm intensity mapping with galaxy surveys is an effective method to extract astrophysical and cosmological information.In this work,we investigate the cross-correlation of MeerKAT single-dish mode HⅠintensity mapping and China Space Station Telescope(CSST)spectroscopic galaxy surveys.We simulate a survey area of~300 deg~2 of MeerKAT and CSST surveys at z=0.5 using MultiDark N-body simulation.The PC A algorithm is applied to remove the foregrounds of HⅠintensity mapping,and signal compensation is considered to solve the signal loss problem in HⅠ-galaxy cross power spectrum caused by the foreground removal process.We find that from CSST galaxy auto and MeerKAT-CSST cross power spectra,the constraint accuracy of the parameter productΩ_(HⅠ)b_(HⅠ)r_(HⅠ,g)can reach~1%,which is about one order of magnitude higher than the current results.After performing the full MeerKAT HⅠintensity mapping survey with5000 deg~2 survey area,the accuracy can be enhanced to<0.3%.This implies that the MeerKAT-CSST cross-correlation can be a powerful tool to probe the cosmic HⅠproperty and the evolution of galaxies and the Universe.展开更多
Background:Pancreatic ductal adenocarcinoma(PDAC)is in urgent need of a second‐line or later‐line treatment strategy.We aimed to analyze the efficacy and safety of additional anlotinib,specifically anlotinib in comb...Background:Pancreatic ductal adenocarcinoma(PDAC)is in urgent need of a second‐line or later‐line treatment strategy.We aimed to analyze the efficacy and safety of additional anlotinib,specifically anlotinib in combination with immunotherapy,in patients with PDAC who have failed first‐line therapy.Methods:Patients with pathological diagnosis of PDAC were additionally treated with anlotinib,and some patients were treated with anti‐PD‐1 agents at the same time,which could be retrospectively analyzed.The efficacy and safety of additional anlotinib were evaluated.Results:A total of 23 patients were included.In patients treated with additional anlotinib,the overall median progression‐free survival(PFS)was 1.8 months and the median overall survival(OS)was 6.3 months,regardless of anti‐PD‐1 agents.Among patients receiving additional anlotinib in combination with anti‐PD‐1 agents,median PFS and OS were 1.8 and 6.5 months,respectively.Adverse events(AEs)were observed in 16 patients(69.6%).In patients treated with additional anlotinib,the majority of AEs were grade 1–3.Univariate analysis revealed that patients with baseline red blood cell distribution width(RDW)<14%treated with additional anlotinib plus anti‐PD‐1 agents had significantly longer OS than patients with baseline RDW≥14%(p=0.025).Patients with additional anlotinib plus anti‐PD‐1 agents as second‐line therapy had a longer OS than those treated as later‐line therapy(p=0.012).Multivariate analysis showed that baseline RDW was the only independent risk factor for OS(p=0.042).Conclusion:The combination of anlotinib and immunotherapy represents an effective add‐on therapy with tolerable AEs as second‐or later‐line therapy in patients with PDAC,particularly in patients with baseline RDW<14%.展开更多
A novel approach to stereodivergent synthesis of carbocyclicα-quaternary amino acid derivatives,bearing two contiguous stereocenters,is proposed through sequential dual Cu/Ir-catalyzed asymmetric allylation and ring-...A novel approach to stereodivergent synthesis of carbocyclicα-quaternary amino acid derivatives,bearing two contiguous stereocenters,is proposed through sequential dual Cu/Ir-catalyzed asymmetric allylation and ring-closing metathesis.A variety of five and six-membered carbocyclicα-quaternary amino acid derivatives could be readily achieved in good to high yields with exclusive regioselectivities,excellent diastereoselectivities(13:1->20:1 dr)and enantioselectivities(generally>99%ee).Of particular note is that the current protocol is also a versatile synthetic tool for the stereodivergent construction of the challenging seven and eight-membered carbocyclicα-amino acid derivatives.All four stereoisomers of these important molecules could be precisely synthesized through the permutation of chiral Cu/Ir catalytic system.The power of this strategy has been demonstrated for the facile access to some biologically active chiral molecules,such as spiro-hydantoins.展开更多
It is a big challenge to well control the porous structure of carbon materials for supercapacitor application.Herein,a simple in-situ self-templating strategy is developed to prepare three-dimensional(3D)hierarchical ...It is a big challenge to well control the porous structure of carbon materials for supercapacitor application.Herein,a simple in-situ self-templating strategy is developed to prepare three-dimensional(3D)hierarchical porous carbons with good combination of micro and meso-porous architecture derived from a new oxygen-bridged porous organic polymer(OPOP).The OPOP is produced by the condensation polymerization of cyanuric chloride and hydroquinone in NaOH ethanol solution and NaCl is in-situ formed as by-product that will serve as template to construct an interconnected 3D hierarchical porous architecture upon carbonization.The large interface pore architecture,and rich doping of N and O heteroatoms effectively promote the electrolyte accessibility and electronic conductivity,and provide abundant active sites for energy storage.Consequently,the supercapacitors based on the optimized OPOP-800 sample display an energy density of 8.44 and 27.28 Wh·kg^(−1)in 6.0 M KOH and 1.0 M Na2SO4 electrolytes,respectively.The capacitance retention is more than 94%after 10,000 cycles.Furthermore,density functional theory(DFT)calculations have been employed to unveil the charge storage mechanism in the OPOP-800.The results presented in this job are inspiring in finely tuning the porous structure to optimize the supercapacitive performance of carbon materials.展开更多
This paper focuses on the higher order fractional differentiability of weak solution pairs to the following nonlinear stationary Stokes system{div A(x-Du)-■π=divF,inΩdivu=0,inΩ.In terms of the difference quotient ...This paper focuses on the higher order fractional differentiability of weak solution pairs to the following nonlinear stationary Stokes system{div A(x-Du)-■π=divF,inΩdivu=0,inΩ.In terms of the difference quotient method,our first result reveals that if F∈B_(p,q.loc)^(β)(Ω,R^(n))for p=2 and 1≤q≤2n/n-2β,then such extra Besov regularity can transfer to the symmetric gradient Du and its pressureπwith no losses under a suitable fractional differentiability assumption on x■A(x,ξ).Furthermore,when the vector field A(x,Du)is simplified to the full gradient■u,we improve the aforementioned Besov regularity for all integrability exponents p and q by establishing a new Campanato-type decay estimates for(■u,π).展开更多
A highly efficient and environment-friendly scale inhibitor(MA-VA-VS)was synthesized via free radical solution polymerization method,where maleic anhydride(MA),vinyl acetate(VA)and vinyl sulfonate(VS)acted as monomers...A highly efficient and environment-friendly scale inhibitor(MA-VA-VS)was synthesized via free radical solution polymerization method,where maleic anhydride(MA),vinyl acetate(VA)and vinyl sulfonate(VS)acted as monomers,while ammonium persulfate was used as initiator.The inhibition performance and the structure as well as properties was characterized using static jar measurement and dynamic test,Fourier transform infrared spectroscopy and thermogravimetric analysis.The surface morphology and composition of scale formed in the solution were examined using scanning electron microscopy and Xray diffraction,respectively.The binding energies of inhibitor with calcite(104)face were calculated using Materials Studio 2017(MS)at 323 K.The results show that the inhibition efficiency gradually increases with increasing inhibitor concentration.While as the Ca2þconcentration increases,the efficiency first increases and then decreases.With the increase in temperature or pH,the efficiency generally decreases.It is confirmed that the inhibition efficiency can reach 91.4%when 150 mg/L MA-VA-VS is used in a flow condition.Both the calculated binding energy and inhibition performance evaluation results demonstrate that the scale inhibition performance of MA-VA-VS is better than a commercial scale inhibitor(HPMA).The excellent inhibition performance of this inhibitor is due to its chelation and dispersion properties.展开更多
Cu-catalyzed endo-selective asymmetric 1,3-dipolar cycloaddition of azomethine ylides with ethenesulfonyl fluorides(ESFs) was successfully developed, this protocol provided an efficient and facile method to a wide ran...Cu-catalyzed endo-selective asymmetric 1,3-dipolar cycloaddition of azomethine ylides with ethenesulfonyl fluorides(ESFs) was successfully developed, this protocol provided an efficient and facile method to a wide range of chiral pyrrolidine-3-sulfonyl fluorides with good to excellent results(up to 87% yield,>20:1 dr, 94% ee). Some other chiral sulfonyl derivatives, such as sulfonamide and sulfonate, were easily accessible through simple transformations with high yields, which demonstrated that the cycloaddition products could be synthetically useful in the sulfur(VI) fluoride exchange(Su FEx) chemistry.展开更多
The electroreduction of CO_(2)(CO_(2)RR)into value-added chemicals is a sustainable strategy for mitigating global warming and managing the global carbon balance.However,developing an efficient and selective catalyst ...The electroreduction of CO_(2)(CO_(2)RR)into value-added chemicals is a sustainable strategy for mitigating global warming and managing the global carbon balance.However,developing an efficient and selective catalyst is still the central challenge.Here,we developed a simple two-step pyrolysis method to confine low-valent Ni-based nanoparticles within nitrogen-doped carbon(Ni-NC).As a result,such Ni-based nanoparticles can effectively reduce CO_(2)to CO,with a maximum CO Faradaic efficiency(FE)of 98%at an overpotential of 0.8 V,as long as good stability.Experimental and the density functional theory(DFT)calculation results reveal that low-valent Ni plays a key role in activity and selectivity enhancement.This study presents a new understanding of Ni-based CO_(2)RR,and provides a simple,scalable approach to the synthesis of low-valent catalysts towards efficient CO_(2)RR.展开更多
基金supported by the National Natural Science Foundation of China (81772369, 81401809, 81373150)CAMS Innovation Fund for Medical Sciences (CIFMS, 2017-I2M-3-001)+1 种基金supported by the Beijing Nova program (Z171100001117110)supported by the Beijing Natural Science Foundation (7192127)
文摘Osteoporosis is characterized by a decrease in bone mass and strength, rendering people prone to osteoporotic fractures caused by low-energy forces. The primary treatment strategy for osteoporotic fractures is surgery;however, the compromised and comminuted bones in osteoporotic fracture sites are not conducive to optimum reduction and rigid fixation. In addition, these patients always exhibit accompanying aging-related disorders, including high inflammatory status, decreased mechanical loading and abnormal skeletal metabolism, which are disadvantages for fracture healing around sites that have undergone orthopedic procedures. Since the incidence of osteoporosis is expected to increase worldwide, orthopedic surgeons should pay more attention to comprehensive strategies for improving the poor prognosis of osteoporotic fractures. Herein, we highlight the molecular basis of osteoimmunology and bone mechanosensation in different healing phases of elderly osteoporotic fractures, guiding perioperative management to alleviate the unfavorable effects of insufficient mechanical loading, high inflammatory levels and pathogen infection. The well-informed pharmacologic and surgical intervention, including treatment with anti-inflammatory drugs and sufficient application of antibiotics, as well as bench-to-bedside strategies for bone augmentation and hardware selection, should be made according to a comprehensive understanding of bone biomechanical properties in addition to the remodeling status of osteoporotic bones, which is necessary for creating proper biological and mechanical environments for bone union and remodeling. Multidisciplinary collaboration will facilitate the improvement of overall osteoporotic care and reduction of secondary fracture incidence.
基金supported by Scientific Research Fund of Hunan Province, PRC (No. 07JJ6141)Scientific Research Fund of Hunan Provincial Education Department, PRC (No. 06C582)
文摘In the course of vehicle license plate （VLP） automatic recognition, tilt correction is a very crucial process. According to Karhunen-Loeve （K-L） transformation, the coordinates of characters in the image are arranged into a two-dimensional covariance matrix, on the basis of which the centered process is carried out. Then, the eigenvector and the rotation angle α are computed in turn. The whole image is rotated by -α. Thus, image horizontal tilt correction is performed. In the vertical tilt correction process, three correction methods, which are K-L transformation method, the line fitting method based on K -means clustering （LFMBKC）, and the line fitting based on least squares （LFMBLS）, are put forward to compute the vertical tilt angle θ. After shear transformation （ST） is imposed on the rotated image, the final correction image is obtained. The experimental results verify that this proposed method can be easily implemented, and can quickly and accurately get the tilt angle. It provides a new effective way for the VLP image tilt correction as well.
基金the support of 2020SKA0110402,MOST-2018YFE0120800National Key R&D Program of China No.2022YFF0503404+5 种基金the National Natural Science Foundation of China(NSFC,Grant Nos.11822305,11773031 and 11633004)support of the National Natural Science Foundation of China(NSFC,Grant Nos.11473044 and 11973047)the Chinese Academy of Sciences grants QYZDJ-SSW-SLH017,XDB23040100,XDA15020200supported by the National Research Foundation of South Africa under Grant Nos.150580,120385 and 120378NIThe CS program“New Insights into Astrophysics and Cosmology with Theoretical Models confronting Observational Data”supported by the science research grants from the China Manned Space Project with NO.CMS-CSST-2021-B01 and CMS-CSST-2021-A01。
文摘Cross-correlating the data on neutral hydrogen(HⅠ)21 cm intensity mapping with galaxy surveys is an effective method to extract astrophysical and cosmological information.In this work,we investigate the cross-correlation of MeerKAT single-dish mode HⅠintensity mapping and China Space Station Telescope(CSST)spectroscopic galaxy surveys.We simulate a survey area of~300 deg~2 of MeerKAT and CSST surveys at z=0.5 using MultiDark N-body simulation.The PC A algorithm is applied to remove the foregrounds of HⅠintensity mapping,and signal compensation is considered to solve the signal loss problem in HⅠ-galaxy cross power spectrum caused by the foreground removal process.We find that from CSST galaxy auto and MeerKAT-CSST cross power spectra,the constraint accuracy of the parameter productΩ_(HⅠ)b_(HⅠ)r_(HⅠ,g)can reach~1%,which is about one order of magnitude higher than the current results.After performing the full MeerKAT HⅠintensity mapping survey with5000 deg~2 survey area,the accuracy can be enhanced to<0.3%.This implies that the MeerKAT-CSST cross-correlation can be a powerful tool to probe the cosmic HⅠproperty and the evolution of galaxies and the Universe.
文摘Background:Pancreatic ductal adenocarcinoma(PDAC)is in urgent need of a second‐line or later‐line treatment strategy.We aimed to analyze the efficacy and safety of additional anlotinib,specifically anlotinib in combination with immunotherapy,in patients with PDAC who have failed first‐line therapy.Methods:Patients with pathological diagnosis of PDAC were additionally treated with anlotinib,and some patients were treated with anti‐PD‐1 agents at the same time,which could be retrospectively analyzed.The efficacy and safety of additional anlotinib were evaluated.Results:A total of 23 patients were included.In patients treated with additional anlotinib,the overall median progression‐free survival(PFS)was 1.8 months and the median overall survival(OS)was 6.3 months,regardless of anti‐PD‐1 agents.Among patients receiving additional anlotinib in combination with anti‐PD‐1 agents,median PFS and OS were 1.8 and 6.5 months,respectively.Adverse events(AEs)were observed in 16 patients(69.6%).In patients treated with additional anlotinib,the majority of AEs were grade 1–3.Univariate analysis revealed that patients with baseline red blood cell distribution width(RDW)<14%treated with additional anlotinib plus anti‐PD‐1 agents had significantly longer OS than patients with baseline RDW≥14%(p=0.025).Patients with additional anlotinib plus anti‐PD‐1 agents as second‐line therapy had a longer OS than those treated as later‐line therapy(p=0.012).Multivariate analysis showed that baseline RDW was the only independent risk factor for OS(p=0.042).Conclusion:The combination of anlotinib and immunotherapy represents an effective add‐on therapy with tolerable AEs as second‐or later‐line therapy in patients with PDAC,particularly in patients with baseline RDW<14%.
基金We are grateful for financial support from the National Natural Science Foundation of China(Grant Nos.21772147,22071186,22071187)the Natural Science Foundation of Hubei Province(Grant Nos.2020CFA036,2021CFA069)the Natural Science Foundation of Jiangsu Province(Grant No.BK20190213).
文摘A novel approach to stereodivergent synthesis of carbocyclicα-quaternary amino acid derivatives,bearing two contiguous stereocenters,is proposed through sequential dual Cu/Ir-catalyzed asymmetric allylation and ring-closing metathesis.A variety of five and six-membered carbocyclicα-quaternary amino acid derivatives could be readily achieved in good to high yields with exclusive regioselectivities,excellent diastereoselectivities(13:1->20:1 dr)and enantioselectivities(generally>99%ee).Of particular note is that the current protocol is also a versatile synthetic tool for the stereodivergent construction of the challenging seven and eight-membered carbocyclicα-amino acid derivatives.All four stereoisomers of these important molecules could be precisely synthesized through the permutation of chiral Cu/Ir catalytic system.The power of this strategy has been demonstrated for the facile access to some biologically active chiral molecules,such as spiro-hydantoins.
基金the National Natural Science Foundation of China(No.21805235)China Postdoctoral Science Foundation(No.2017M610502)+2 种基金the Opening Foundation of Creative Platform of the Key Laboratory of the Education Department of Hunan Province(No.20K131)the Construct Program of the Key Discipline in Hunan Province is greatly acknowledged.H.C.and Z.G.L.thank the support from the Basic Research Project of the Science and Technology Innovation Commission of Shenzhen(No.JCYJ20170817110251498)Shenzhen Key Laboratory of Interfacial Science and Engineering of Materials(No.ZDSYS20200421111401738).
文摘It is a big challenge to well control the porous structure of carbon materials for supercapacitor application.Herein,a simple in-situ self-templating strategy is developed to prepare three-dimensional(3D)hierarchical porous carbons with good combination of micro and meso-porous architecture derived from a new oxygen-bridged porous organic polymer(OPOP).The OPOP is produced by the condensation polymerization of cyanuric chloride and hydroquinone in NaOH ethanol solution and NaCl is in-situ formed as by-product that will serve as template to construct an interconnected 3D hierarchical porous architecture upon carbonization.The large interface pore architecture,and rich doping of N and O heteroatoms effectively promote the electrolyte accessibility and electronic conductivity,and provide abundant active sites for energy storage.Consequently,the supercapacitors based on the optimized OPOP-800 sample display an energy density of 8.44 and 27.28 Wh·kg^(−1)in 6.0 M KOH and 1.0 M Na2SO4 electrolytes,respectively.The capacitance retention is more than 94%after 10,000 cycles.Furthermore,density functional theory(DFT)calculations have been employed to unveil the charge storage mechanism in the OPOP-800.The results presented in this job are inspiring in finely tuning the porous structure to optimize the supercapacitive performance of carbon materials.
基金Supported by the National Natural Science Foundation of China(Grant Nos.12071229,12101452)Tianjin Normal University Doctoral Research Project(Grant No.52XB2110)。
文摘This paper focuses on the higher order fractional differentiability of weak solution pairs to the following nonlinear stationary Stokes system{div A(x-Du)-■π=divF,inΩdivu=0,inΩ.In terms of the difference quotient method,our first result reveals that if F∈B_(p,q.loc)^(β)(Ω,R^(n))for p=2 and 1≤q≤2n/n-2β,then such extra Besov regularity can transfer to the symmetric gradient Du and its pressureπwith no losses under a suitable fractional differentiability assumption on x■A(x,ξ).Furthermore,when the vector field A(x,Du)is simplified to the full gradient■u,we improve the aforementioned Besov regularity for all integrability exponents p and q by establishing a new Campanato-type decay estimates for(■u,π).
基金by 111 Project[D18016]Application and Fundamental Research of Sichuan Province[grant number 2017JY0171]Scientific and Technological Innovation Team for the Safety of Petroleum Tubular Goods in Southwest Petroleum University[grant number 2018CXTD01]。
文摘A highly efficient and environment-friendly scale inhibitor(MA-VA-VS)was synthesized via free radical solution polymerization method,where maleic anhydride(MA),vinyl acetate(VA)and vinyl sulfonate(VS)acted as monomers,while ammonium persulfate was used as initiator.The inhibition performance and the structure as well as properties was characterized using static jar measurement and dynamic test,Fourier transform infrared spectroscopy and thermogravimetric analysis.The surface morphology and composition of scale formed in the solution were examined using scanning electron microscopy and Xray diffraction,respectively.The binding energies of inhibitor with calcite(104)face were calculated using Materials Studio 2017(MS)at 323 K.The results show that the inhibition efficiency gradually increases with increasing inhibitor concentration.While as the Ca2þconcentration increases,the efficiency first increases and then decreases.With the increase in temperature or pH,the efficiency generally decreases.It is confirmed that the inhibition efficiency can reach 91.4%when 150 mg/L MA-VA-VS is used in a flow condition.Both the calculated binding energy and inhibition performance evaluation results demonstrate that the scale inhibition performance of MA-VA-VS is better than a commercial scale inhibitor(HPMA).The excellent inhibition performance of this inhibitor is due to its chelation and dispersion properties.
基金the financial support from the National Natural Science Foundation of China (Nos. 21772147, 22071186, 22071187)Natural Science Foundation of Hubei Province (No. 2020CFA036)+1 种基金Natural Science Foundation of Jiangsu Province (No. SKB2019041078)The Program of Introducing Talents of Discipline to Universities of China (111 Project) is also appreciated。
文摘Cu-catalyzed endo-selective asymmetric 1,3-dipolar cycloaddition of azomethine ylides with ethenesulfonyl fluorides(ESFs) was successfully developed, this protocol provided an efficient and facile method to a wide range of chiral pyrrolidine-3-sulfonyl fluorides with good to excellent results(up to 87% yield,>20:1 dr, 94% ee). Some other chiral sulfonyl derivatives, such as sulfonamide and sulfonate, were easily accessible through simple transformations with high yields, which demonstrated that the cycloaddition products could be synthetically useful in the sulfur(VI) fluoride exchange(Su FEx) chemistry.
基金the financial support from the Shenzhen Science and Technology Research Grant(No.JCYJ20200109140416788,China)the Chemistry and Chemical Engineering Guangdong Laboratory(No.1922018,China)National Key R&D Program of China(No.2020YFB0704500)。
文摘The electroreduction of CO_(2)(CO_(2)RR)into value-added chemicals is a sustainable strategy for mitigating global warming and managing the global carbon balance.However,developing an efficient and selective catalyst is still the central challenge.Here,we developed a simple two-step pyrolysis method to confine low-valent Ni-based nanoparticles within nitrogen-doped carbon(Ni-NC).As a result,such Ni-based nanoparticles can effectively reduce CO_(2)to CO,with a maximum CO Faradaic efficiency(FE)of 98%at an overpotential of 0.8 V,as long as good stability.Experimental and the density functional theory(DFT)calculation results reveal that low-valent Ni plays a key role in activity and selectivity enhancement.This study presents a new understanding of Ni-based CO_(2)RR,and provides a simple,scalable approach to the synthesis of low-valent catalysts towards efficient CO_(2)RR.
