Porous intermetallics show potential in the field of filtration and separation as well as in the field of catalysis.Herein,porous Ti Fe2intermetallics were fabricated by the reactive synthesis of elemental powders.The...Porous intermetallics show potential in the field of filtration and separation as well as in the field of catalysis.Herein,porous Ti Fe2intermetallics were fabricated by the reactive synthesis of elemental powders.The phase transformation and pore formation of porous TiFe2intermetallics were investigated,and its corrosion behavior and hydrogen evolution reaction(HER)performance in alkali solution were studied.Porous TiFe2intermetallics with porosity in the range of 34.4%-56.4%were synthesized by the diffusion reaction of Ti and Fe elements,and the pore formation of porous TiFe2intermetallic compound is the result of a combination of the bridging effect and the Kirkendall effect.The porous TiFe2samples exhibit better corrosion resistance compared with porous 316L stainless steel,which is related to the formation of uniform nanosheets on the surface that hinder further corrosion,and porous TiFe2electrode shows the overpotential of 220.6 and 295.6 mV at 10 and 100 mA·cm-2,suggesting a good catalytic performance.The synthesized porous Fe-based intermetallic has a controllable pore structure as well as excellent corrosion resistance,showing its potential in the field of filtration and separation.展开更多
This novel study identifi es the effective anti-inflammatory phenolic compounds in dandelion and provides mechanistic insights into their interactions with receptor proteins(toll-like receptor 4,TLR4;co-receptor myelo...This novel study identifi es the effective anti-inflammatory phenolic compounds in dandelion and provides mechanistic insights into their interactions with receptor proteins(toll-like receptor 4,TLR4;co-receptor myeloid differentiation protein-2,MD-2)using UHPLC-ESI-MS/MS,lipopolysaccharide(LPS)-stimulated THP-1 cell line,fluorescence quenching and anisotropy,molecular docking(single ligand and multi-ligand docking)and molecular dynamics simulation.A 50%aqueous methanol extract had a greater anti-inflammatory effect and higher chicoric acid content,compared with the 100%water and 100%methanol extracts.Chicoric acid,chlorogenic acid,methylophiopogonone A,caffeic acid,gallic acid monohydrate and 4’-O-demethylbroussonin A had relatively high binding energies and contents in all extracts.Chicoric acid competed with chlorogenic acid,4’-O-demethylbroussonin A and quercetin for MD-2.Among dandelion’s phenolics,chicoric acid most effectively hindered TLR4-MD-2 complex formation,with a quenching constant of 0.62×10^(6) L/mol for MD-2 or TLR4 at 320 K,and binding energies of-6.87 and-5.97 kcal/mol,respectively,for MD-2 and TLR4.展开更多
A simple and efficient method for the iodination of aromatic compounds has been achieved in the presence of iodine and 1,4- bis（triphenylphosphonium）-2-butene peroxodisulfate.
Photodegradation ofpentachlorophenol （PCP） and p-nitrophenol （PNP） in soil was carried out in a designed rotary reactor, which can provide the soil particles with continually uniform irradiation, and on a series o...Photodegradation ofpentachlorophenol （PCP） and p-nitrophenol （PNP） in soil was carried out in a designed rotary reactor, which can provide the soil particles with continually uniform irradiation, and on a series of thin soil layers. TiO2, as a kind of environmental friendly photocatalyst, was introduced to the soil to enhance the processes. Compared with that on the soil layers, photodegradation of PCP at initial concentration of 60 mg/kg was improved dramatically in the rotary reactor no matter whether TiO2 was added, with an increase of 3.0 times in the apparent first-order rate constants. The addition of 1 wt% TiO2 furthered the improvement by 1.4 times. Without addition of TiO2, PNP （initial concentration of 60 mg/kg） photodegradation rate in the rotary reactor was similar to that on the soil layers. When 1 wt% additional TiO2 was added, PNP photodegradation was enhanced obviously, and the enhancement in the rotary reactor was 2 times of that on the soil layers, which may be attributed to the higher frequency of the contact between PNP on soil particles and the photocatalyst. The effect of soil pH and initial concentrations of the target compounds on the photodegradation in the rotary reactor was investigated. The order of the degradation rate at different soil pH was relative to the aggregation of soil particles during mixing in the rotary reactor. Photodegradation of PCP and PNP at different initial concentrations showed that addition of TiO2 to enhance the photodegradation was more suitable for contaminated soil with higher concentration of PCP, while was effective for contaminated soil at each PNP concentration tested in our study.展开更多
Si is considered as the promising anode materials for lithium-ion batteries(LIBs)owing to their high capacities of 4200 mAh g-1and natural abundancy.However,severe electrode pulverization and poor electronic and Li-io...Si is considered as the promising anode materials for lithium-ion batteries(LIBs)owing to their high capacities of 4200 mAh g-1and natural abundancy.However,severe electrode pulverization and poor electronic and Li-ionic conductivities hinder their practical applications.To resolve the afore-mentioned problems,we first demonstrate a cation-mixed disordered lattice and unique Li storage mechanism of single-phase ternary GaSiP_(2)compound,where the liquid metallic Ga and highly reactive P are incorporated into Si through a ball milling method.As confirmed by experimental and theoretical analyses,the introduced Ga and P enables to achieve the stronger resistance against volume variation and metallic conductivity,respectively,while the cation-mixed lattice provides the faster Li-ionic diffusion capability than those of the parent GaP and Si phases.The resulting GaSiP_(2)electrodes delivered the high specific capacity of 1615 mAh g-1and high initial Coulombic efficiency of 91%,while the graphite-modified GaSiP_(2)(GaSiP_(2)@C)achieved 83%of capacity retention after 900 cycles and high-rate capacity of 800 at 10,000 mA g-1.Furthermore,the LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)//Ga SiP_(2)@C full cells achieved the high specific capacity of 1049 mAh g-1after 100 cycles,paving a way for the rational design of high-performance LIB anode materials.展开更多
Two Pb^Ⅱ coordination polymers [Pb（oba）（2,2′-bipy）]·1.5H2O（1） and [Pb（oba）（phen）]（2）（H2oba = 2,4-oxybis（benzoic acid）, 2,2′-bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline） were synthesized...Two Pb^Ⅱ coordination polymers [Pb（oba）（2,2′-bipy）]·1.5H2O（1） and [Pb（oba）（phen）]（2）（H2oba = 2,4-oxybis（benzoic acid）, 2,2′-bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline） were synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction, thermogravimetric analyses, IR spectroscopy and elemental analysis. Structures of compounds 1 and 2 are similar. Compounds 1 and 2 show 1D wavy chains, which are further connected through aromatic π-π stacking interactions to expand into 2D wavelike networks. The crystal structure of 2,4-oxybis（benzoic acid） ligand（3） was obtained, and its full geometry optimization was carried out by using DFT methods at the B3LYP/6-31G（d） level. The calculated data show that the bond distances and bond angles were very close to the experimental data. The values of the frontier orbital energies indicate that this configuration is stable. Moreover, the solid-state fluorescence properties of 1-3 have also been investigated.展开更多
The compound ingots of Pr0.15TbxDy0.85-xFe2 (x=0 to 0.85) were prepared by arc melting in a water Cu boat using arc furnace under a purified Ar atmosphere. Appropriate annealing (850℃, 100 h) can obtain single Laves ...The compound ingots of Pr0.15TbxDy0.85-xFe2 (x=0 to 0.85) were prepared by arc melting in a water Cu boat using arc furnace under a purified Ar atmosphere. Appropriate annealing (850℃, 100 h) can obtain single Laves phase compound. The magnetostriction for these systems will rise obviously when partially substituted Tb or Dy by Pr.展开更多
Michael addition of nitroalkanes to α,β-unsaturated carbonyl compounds occurs in the presence of KF/AI_2O_3/PEG4000 without solvent.Yields are fair to good and work-ups are easy.
The crystal structure, magnetic and magnetocaloric properties of(Ho_(1-x) Y_(0.5))_5 Pd_2 compounds are investigated. All the compounds crystallize in a cubic Dy_5 Pd_2-type structure with the space group Fd3 m and un...The crystal structure, magnetic and magnetocaloric properties of(Ho_(1-x) Y_(0.5))_5 Pd_2 compounds are investigated. All the compounds crystallize in a cubic Dy_5 Pd_2-type structure with the space group Fd3 m and undergo a second order transition from spin glass(SG) state to paramagnetic(PM) state. The spin glass transition temperatures T_g decrease from 26 K for x = 0 to 13 K for x = 0.5. In the PM region, the reciprocal susceptibilities for all the compounds obey the Curie–Weiss law. The paramagnetic Curie temperatures(θp) for Ho_5 Pd_2,(Ho_(0.75) Y_(0.25)_5 Pd_2, and(Ho_(0.5) Y_(0.5))_5 Pd_2 are determined to be 32 K, 30 K, and 22 K, respectively, and the corresponding effective magnetic moments(μeff) are10.8 μB/Ho, 10.3 μB/RE, and 7.5 μB/RE, respectively. Magnetocaloric effect(MCE) is anticipated according to the Maxwell relation, based on the isothermal magnetization curves. For a magnetic field change of 0–5 T, the maximum values of the isothermal magnetic entropy change-?SMof the(Ho_(1-x)Y_x)_5 Pd_2(x = 0, 0.25, and 0.5) compounds are determined to be 11.5 J·kg^(-1)·K^(-1), 11.1 J·kg^(-1)·K^(-1), and 8.9 K J·kg^(-1)·K^(-1), with corresponding refrigerant capacity values of 382.3 J·kg^(-1), 336.2 J·kg^(-1), and 242.5 J·kg^(-1), respectively.展开更多
Coronavirus pandemic infection is the most important health issue worldwide.Coronavirus disease 2019 is a contagious disease characterized by severe acute respiratory syndrome coronavirus 2.To date,excluding the possi...Coronavirus pandemic infection is the most important health issue worldwide.Coronavirus disease 2019 is a contagious disease characterized by severe acute respiratory syndrome coronavirus 2.To date,excluding the possibility of vaccination,against SARS-CoV-2 infection it is possible to act only with supportive care and non-virus-specific treatments in order to improve the patient’s symptoms.Pharmaceutical industry is investigating effects of medicinal plants,phytochemical extracts and aromatic herbs to find out natural substances which may act as antiviral drugs.Several studies have revealed how these substances may interfere with the viral life cycle,viral entry,replication,assembly or discharge,as well as virus-specific host targets or stimulating the host immune system,reducing oxidative stress and inflammatory response.A natural compound can be used as a prophylaxis by people professionally exposed to the risk of contagion and/or positive patients not in intensive care.The aim of this paper is to perform a narrative review of current literature in order to summarize the most studied natural compounds and their modes of action.展开更多
Converting carbon dioxide(CO2)into value-added chemicals by CO2 reduction has been considered as a potential way to solve the current energy crisis and environmental problem.Among the methods of CO2 reduction,the elec...Converting carbon dioxide(CO2)into value-added chemicals by CO2 reduction has been considered as a potential way to solve the current energy crisis and environmental problem.Among the methods of CO2 reduction,the electrochemical method has been widely used due to its mild reaction condition and high reaction efficiency.In the electrochemical reduction system,the CO2 electrocatalyst is the most important part.Although many CO2 electrocatalysts have been developed,efficient catalysts with high activity,selectivity and stability are still lacking.Copper sulfide compound,as a low-toxicity and emerging material,has broad prospects in the field of CO2 reduction due to its unique structural and electrochemical properties.Much progress has been achieved with copper sulfide nanocrystalline and the field is rapidly developing.This paper summarizes the preparation,recent progress in development,and factors affecting the electrocatalytic CO2 reduction performance with copper sulfide compound as a catalyst.Prospects for future development are also outlined,with the aim of using copper sulfide compound as a highly active and stable electrocatalyst for CO2 reduction.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51971251)。
文摘Porous intermetallics show potential in the field of filtration and separation as well as in the field of catalysis.Herein,porous Ti Fe2intermetallics were fabricated by the reactive synthesis of elemental powders.The phase transformation and pore formation of porous TiFe2intermetallics were investigated,and its corrosion behavior and hydrogen evolution reaction(HER)performance in alkali solution were studied.Porous TiFe2intermetallics with porosity in the range of 34.4%-56.4%were synthesized by the diffusion reaction of Ti and Fe elements,and the pore formation of porous TiFe2intermetallic compound is the result of a combination of the bridging effect and the Kirkendall effect.The porous TiFe2samples exhibit better corrosion resistance compared with porous 316L stainless steel,which is related to the formation of uniform nanosheets on the surface that hinder further corrosion,and porous TiFe2electrode shows the overpotential of 220.6 and 295.6 mV at 10 and 100 mA·cm-2,suggesting a good catalytic performance.The synthesized porous Fe-based intermetallic has a controllable pore structure as well as excellent corrosion resistance,showing its potential in the field of filtration and separation.
基金supported by the funding“Innovation Project of Shandong Province Agricultural Application Technology”(2130106)“Key Technology Research and Development Program of Shandong”(2019GNC106004).
文摘This novel study identifi es the effective anti-inflammatory phenolic compounds in dandelion and provides mechanistic insights into their interactions with receptor proteins(toll-like receptor 4,TLR4;co-receptor myeloid differentiation protein-2,MD-2)using UHPLC-ESI-MS/MS,lipopolysaccharide(LPS)-stimulated THP-1 cell line,fluorescence quenching and anisotropy,molecular docking(single ligand and multi-ligand docking)and molecular dynamics simulation.A 50%aqueous methanol extract had a greater anti-inflammatory effect and higher chicoric acid content,compared with the 100%water and 100%methanol extracts.Chicoric acid,chlorogenic acid,methylophiopogonone A,caffeic acid,gallic acid monohydrate and 4’-O-demethylbroussonin A had relatively high binding energies and contents in all extracts.Chicoric acid competed with chlorogenic acid,4’-O-demethylbroussonin A and quercetin for MD-2.Among dandelion’s phenolics,chicoric acid most effectively hindered TLR4-MD-2 complex formation,with a quenching constant of 0.62×10^(6) L/mol for MD-2 or TLR4 at 320 K,and binding energies of-6.87 and-5.97 kcal/mol,respectively,for MD-2 and TLR4.
文摘A simple and efficient method for the iodination of aromatic compounds has been achieved in the presence of iodine and 1,4- bis（triphenylphosphonium）-2-butene peroxodisulfate.
基金The National Basic Research Program of China (No. 2004CB418504 2003CB415006)
文摘Photodegradation ofpentachlorophenol （PCP） and p-nitrophenol （PNP） in soil was carried out in a designed rotary reactor, which can provide the soil particles with continually uniform irradiation, and on a series of thin soil layers. TiO2, as a kind of environmental friendly photocatalyst, was introduced to the soil to enhance the processes. Compared with that on the soil layers, photodegradation of PCP at initial concentration of 60 mg/kg was improved dramatically in the rotary reactor no matter whether TiO2 was added, with an increase of 3.0 times in the apparent first-order rate constants. The addition of 1 wt% TiO2 furthered the improvement by 1.4 times. Without addition of TiO2, PNP （initial concentration of 60 mg/kg） photodegradation rate in the rotary reactor was similar to that on the soil layers. When 1 wt% additional TiO2 was added, PNP photodegradation was enhanced obviously, and the enhancement in the rotary reactor was 2 times of that on the soil layers, which may be attributed to the higher frequency of the contact between PNP on soil particles and the photocatalyst. The effect of soil pH and initial concentrations of the target compounds on the photodegradation in the rotary reactor was investigated. The order of the degradation rate at different soil pH was relative to the aggregation of soil particles during mixing in the rotary reactor. Photodegradation of PCP and PNP at different initial concentrations showed that addition of TiO2 to enhance the photodegradation was more suitable for contaminated soil with higher concentration of PCP, while was effective for contaminated soil at each PNP concentration tested in our study.
基金supported by National Natural Science Foundation of China(No.22178068)the Brain Pool(BP)program(No.2021H1D3A2A02045576)funded by National Research Foundation of KoreaNational Research Foundation of Korea grant funded by the Korea government(MSIT)(No.NRF-2020R1A3B2079803 and No.2021M3D1A2043791)。
文摘Si is considered as the promising anode materials for lithium-ion batteries(LIBs)owing to their high capacities of 4200 mAh g-1and natural abundancy.However,severe electrode pulverization and poor electronic and Li-ionic conductivities hinder their practical applications.To resolve the afore-mentioned problems,we first demonstrate a cation-mixed disordered lattice and unique Li storage mechanism of single-phase ternary GaSiP_(2)compound,where the liquid metallic Ga and highly reactive P are incorporated into Si through a ball milling method.As confirmed by experimental and theoretical analyses,the introduced Ga and P enables to achieve the stronger resistance against volume variation and metallic conductivity,respectively,while the cation-mixed lattice provides the faster Li-ionic diffusion capability than those of the parent GaP and Si phases.The resulting GaSiP_(2)electrodes delivered the high specific capacity of 1615 mAh g-1and high initial Coulombic efficiency of 91%,while the graphite-modified GaSiP_(2)(GaSiP_(2)@C)achieved 83%of capacity retention after 900 cycles and high-rate capacity of 800 at 10,000 mA g-1.Furthermore,the LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)//Ga SiP_(2)@C full cells achieved the high specific capacity of 1049 mAh g-1after 100 cycles,paving a way for the rational design of high-performance LIB anode materials.
基金supported by the Natural Scientific Research and Overall innovation plan major project of Shaanxi Provincial Education Office of China(No.2012KTCL03-16)the National Natural Science Foundation of China(No.21373178)+2 种基金the Natural Scientific Research Foundation of Shaanxi Provincial Education Office(No.2013Jk0668)the National College Students'innovation and entrepreneurship training program(201310719002)the special fund of Yan’an University(No.YDZ2013-10)
文摘Two Pb^Ⅱ coordination polymers [Pb（oba）（2,2′-bipy）]·1.5H2O（1） and [Pb（oba）（phen）]（2）（H2oba = 2,4-oxybis（benzoic acid）, 2,2′-bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline） were synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction, thermogravimetric analyses, IR spectroscopy and elemental analysis. Structures of compounds 1 and 2 are similar. Compounds 1 and 2 show 1D wavy chains, which are further connected through aromatic π-π stacking interactions to expand into 2D wavelike networks. The crystal structure of 2,4-oxybis（benzoic acid） ligand（3） was obtained, and its full geometry optimization was carried out by using DFT methods at the B3LYP/6-31G（d） level. The calculated data show that the bond distances and bond angles were very close to the experimental data. The values of the frontier orbital energies indicate that this configuration is stable. Moreover, the solid-state fluorescence properties of 1-3 have also been investigated.
基金the Natural Science Foundation of Hebei Province 596028 and the National NaturalScience Foundation of China No.59871062.
文摘The compound ingots of Pr0.15TbxDy0.85-xFe2 (x=0 to 0.85) were prepared by arc melting in a water Cu boat using arc furnace under a purified Ar atmosphere. Appropriate annealing (850℃, 100 h) can obtain single Laves phase compound. The magnetostriction for these systems will rise obviously when partially substituted Tb or Dy by Pr.
文摘Michael addition of nitroalkanes to α,β-unsaturated carbonyl compounds occurs in the presence of KF/AI_2O_3/PEG4000 without solvent.Yields are fair to good and work-ups are easy.
基金Project supported by the National Basic Research Program of China(Grant No.2014CB643703)the National Key Research and Development Program of China(Grant No.2016YFB0700901)+1 种基金the National Natural Science Foundation of China(Grant Nos.51261004 and 51761007)Guangxi Natural Science Foundation,China(Grant No.2018GXNSFAA294051)
文摘The crystal structure, magnetic and magnetocaloric properties of(Ho_(1-x) Y_(0.5))_5 Pd_2 compounds are investigated. All the compounds crystallize in a cubic Dy_5 Pd_2-type structure with the space group Fd3 m and undergo a second order transition from spin glass(SG) state to paramagnetic(PM) state. The spin glass transition temperatures T_g decrease from 26 K for x = 0 to 13 K for x = 0.5. In the PM region, the reciprocal susceptibilities for all the compounds obey the Curie–Weiss law. The paramagnetic Curie temperatures(θp) for Ho_5 Pd_2,(Ho_(0.75) Y_(0.25)_5 Pd_2, and(Ho_(0.5) Y_(0.5))_5 Pd_2 are determined to be 32 K, 30 K, and 22 K, respectively, and the corresponding effective magnetic moments(μeff) are10.8 μB/Ho, 10.3 μB/RE, and 7.5 μB/RE, respectively. Magnetocaloric effect(MCE) is anticipated according to the Maxwell relation, based on the isothermal magnetization curves. For a magnetic field change of 0–5 T, the maximum values of the isothermal magnetic entropy change-?SMof the(Ho_(1-x)Y_x)_5 Pd_2(x = 0, 0.25, and 0.5) compounds are determined to be 11.5 J·kg^(-1)·K^(-1), 11.1 J·kg^(-1)·K^(-1), and 8.9 K J·kg^(-1)·K^(-1), with corresponding refrigerant capacity values of 382.3 J·kg^(-1), 336.2 J·kg^(-1), and 242.5 J·kg^(-1), respectively.
文摘Coronavirus pandemic infection is the most important health issue worldwide.Coronavirus disease 2019 is a contagious disease characterized by severe acute respiratory syndrome coronavirus 2.To date,excluding the possibility of vaccination,against SARS-CoV-2 infection it is possible to act only with supportive care and non-virus-specific treatments in order to improve the patient’s symptoms.Pharmaceutical industry is investigating effects of medicinal plants,phytochemical extracts and aromatic herbs to find out natural substances which may act as antiviral drugs.Several studies have revealed how these substances may interfere with the viral life cycle,viral entry,replication,assembly or discharge,as well as virus-specific host targets or stimulating the host immune system,reducing oxidative stress and inflammatory response.A natural compound can be used as a prophylaxis by people professionally exposed to the risk of contagion and/or positive patients not in intensive care.The aim of this paper is to perform a narrative review of current literature in order to summarize the most studied natural compounds and their modes of action.
基金the National Postdoctoral Program for Innovative Talents of China,Postdoctoral Science Foundation of China(Grant No.2018M640759)Natural Science Foundation of China(Grant No.21872174 and U1932148)+4 种基金Project of Innovation-Driven Plan in Central South University(Grant No.20180018050001)State Key Laboratory of Powder Metallurgy,International Science and Technology Cooperation Program(Grant No.2017YFE0127800)Hunan Provincial Science and Technology Program(2017XK2026)Shenzhen Science and Technology Innovation Project(Grant No.JCYJ20180307151313532)Thousand Youth Talents Plan of China and Hundred Youth Talents Program of Hunan.
文摘Converting carbon dioxide(CO2)into value-added chemicals by CO2 reduction has been considered as a potential way to solve the current energy crisis and environmental problem.Among the methods of CO2 reduction,the electrochemical method has been widely used due to its mild reaction condition and high reaction efficiency.In the electrochemical reduction system,the CO2 electrocatalyst is the most important part.Although many CO2 electrocatalysts have been developed,efficient catalysts with high activity,selectivity and stability are still lacking.Copper sulfide compound,as a low-toxicity and emerging material,has broad prospects in the field of CO2 reduction due to its unique structural and electrochemical properties.Much progress has been achieved with copper sulfide nanocrystalline and the field is rapidly developing.This paper summarizes the preparation,recent progress in development,and factors affecting the electrocatalytic CO2 reduction performance with copper sulfide compound as a catalyst.Prospects for future development are also outlined,with the aim of using copper sulfide compound as a highly active and stable electrocatalyst for CO2 reduction.
