Fe/N-based biomass porous carbon composite(Fe/N-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/N-p Carbon on the thermal decomposition of energetic molecular...Fe/N-based biomass porous carbon composite(Fe/N-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/N-p Carbon on the thermal decomposition of energetic molecular perovskite-based material DAP-4 was studied.Biomass porous carbonaceous materials was considered as the micro/nano support layers for in situ deposition of Fe/N precursors.Fe/Np Carbon was prepared simply by the high-temperature carbonization method.It was found that it showed the inherent catalysis properties for thermal decomposition of DAP-4.The heat release of DAP-4/Fe/N-p Carbon by DSC curves tested had increased slightly,compared from DAP-4/Fe/N-p Carbon-0.The decomposition temperature peak of DAP-4 at the presence of Fe/N-p Carbon had reduced by 79°C from384.4°C(pure DAP-4) to 305.4°C(DAP-4/Fe/N-p Carbon-3).The apparent activation energy of DAP-4thermal decomposition also had decreased by 29.1 J/mol.The possible catalytic decomposition mechanism of DAP-4 with Fe/N-p Carbon was proposed.展开更多
(a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of po...(a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of poly-BLG at variable DP;(d)Reaction rates of LiHMDS and hexylamine initiated BLGNCA polymerization in THF with NCA:initiator ratio of 100∶1 and initial NCA concentration at 0.2 mol/L;(e)CD spectra of poly-BLG at variable DP prepared from LiHMDS-initiated NCA polymerization.展开更多
Monodispersed dihydrated zinc oxalate(ZnC_2O_4·2H_2O) particles with characteristic morphology were synthesized by aging a mixed solution of zinc nitrate(Zn(NO_3)_2) and sodium oxalate(Na_2C_2O_4) in the presence...Monodispersed dihydrated zinc oxalate(ZnC_2O_4·2H_2O) particles with characteristic morphology were synthesized by aging a mixed solution of zinc nitrate(Zn(NO_3)_2) and sodium oxalate(Na_2C_2O_4) in the presence of a citrate ligand, with an average flat size of approximately 10–15 μm. The important parameters, including the solution pH values and the concentration of the zinc ions and citrate ligand, were investigated using a series of experiments. It is verified that the citrate ligand significantly affects the morphology of zinc oxalate particles, probably via its multiple roles of chelating, dispersing, and selective absorption. Thermodynamic equilibrium of the distribution of zinc species in an aqueous solution of Zn(Ⅱ)-citrate-oxalate-H_2O was estimated to explain the experimental results and to clarify the size and morphological evolution mechanism of the precipitated particles.展开更多
A praedcal opthesis of trans-3,4-aiol derivatives of subnituted chromans via epoxidation with combined use of mangenese (III) salen complex 3 and hydrgen perokide has been developed. These diol derivatives are key int...A praedcal opthesis of trans-3,4-aiol derivatives of subnituted chromans via epoxidation with combined use of mangenese (III) salen complex 3 and hydrgen perokide has been developed. These diol derivatives are key intermediates for the syntheis of a series of biologicallimportant chroman compounds.展开更多
Nitroalkanes react smoothly with CF3CCl2COCH=CHPh via Michael addition in the presence of inorganic bases such as KF/Al2O3 or K2CO3, giving fluorinecontaining γ-nitro ketones in good yields.
In a facile procedure, 2-(1, 3-dithian-2-ylidene)-l-arylketones 1 vere reduced with magnesium in methanol to give α-aryl-β-(1, 3-dithane) alcohols 2 in good to high yields.
Plumbagic acid[β-(2,3-dihydroxybenzoyl)butyric acid](1),hasbeen synthesized from commcrcially available catechol by two facile routeswith overall yields of 18.6% and 53.5%,rcspectively.
The attractive and impertan complexes, manganese porphyrin aromatic thiolates, are prepared directly by the reaction of chloro(5, 10, 15, 20-tetraphenylporphyrinato) manganese Mn(TPP)Cl with PhSNa and (p-NO2)PhSNa und...The attractive and impertan complexes, manganese porphyrin aromatic thiolates, are prepared directly by the reaction of chloro(5, 10, 15, 20-tetraphenylporphyrinato) manganese Mn(TPP)Cl with PhSNa and (p-NO2)PhSNa under extremely simple and mild reaction展开更多
Air-stable cationic organobismuth complexes (2-5) possessing both acidic and basic characters were synthesized. The catalyst system that comprises an air-stable bifunctional Lewis acidic/basic organobismuth complex an...Air-stable cationic organobismuth complexes (2-5) possessing both acidic and basic characters were synthesized. The catalyst system that comprises an air-stable bifunctional Lewis acidic/basic organobismuth complex and [Bmim]BF4 showed high catalytic activity, diastereoselec-tivity, stability, and reusability in the one-pot synthesis of (E)-α,β-unsaturat-ed ketones through highly selective crossed-condensation of ketones and aldehydes. Through switching the reaction from homogeneous to heterogeneous, the system shows facile separation ability and facile reusability.展开更多
of main observation and conclusion Magnetic hydrogels have found extensive applications in fields such as soft robotics,drug delivery and shape morphing.Here a facile method was fabricated to prepare polysaccharide-ba...of main observation and conclusion Magnetic hydrogels have found extensive applications in fields such as soft robotics,drug delivery and shape morphing.Here a facile method was fabricated to prepare polysaccharide-based magnetic hydrogels.The chitosan-Fe3O4 ferrofluid was obtained by dispersing carboxyl groups modified Fe3O4 nanoparticles uniformly in chitosan matrix.Subsequently,the magnetic polysaccharide hydrogel was obtained by simply mixing cellulose acetoacetate solution with chitosan-Fe3O4 ferrofluid.The structures and properties of the magnetic hydrogel were analyzed using Fourier-transform infrared spectroscopy,rheological recovery,responsiveness,and stability measurements.The results indicated that magnetic polysaccharide hydrogel showed pH responsiveness and excellent self-healing properties,and the hydrogel manifested outstanding stability under physiological conditions(37℃)for 72 h.In addition,the injectable polysaccharide-based hydrogel exhibited sensitive magnetic responsive and shape-shifting ability under an external magnetic field.Therefore,the strategy for the facile preparation of the magnetic polysaccharide-based hydrogel in this work could provide a benign and versatile method for achieving self-healing,responsive,injectable properties for the application in biomedical fields.展开更多
Mg2+in MgAl-layered double hydroxides nanoparticles was substituted with different divalent transition metal ions(MAl-LDHs,M:Mg2+,Cu2+,Ni2+,Co2+,and Mn2+)via a facile method to be used as antibacterial agents.The phas...Mg2+in MgAl-layered double hydroxides nanoparticles was substituted with different divalent transition metal ions(MAl-LDHs,M:Mg2+,Cu2+,Ni2+,Co2+,and Mn2+)via a facile method to be used as antibacterial agents.The phase structural and morphological characterizations of MAl-LDHs were investigated by XRD,FTIR spectroscopy and TEM.The results have shown that all of MAl-LDHs had typical layered structures except MnAl-LDH which contained Mn304 phases.Particular morphology of MnAl-LDH with ellipsoids,spherical and rod-like structure and CuAl-LDH with rod-like shape existed.IC50(the concentrations providing 50%antibacterial activity)values of CuAl-LDH,NiAl-LDH,CoAl-LDH,and MnAlLDH in broth dilution tests were^800-1500μg/mL.Dosages of CuAl-LDH,CoAl-LDH,and MnAl-LDH with>10 mm inhibition zone in disk diffusion tests were^150-300μg/disk.Antibacterial mechanism of MAl-LDHs may be attributed to the synergistic factors including effected surroundings,surface interactions,morphology of particles,ROS and metal ions.The results indicate a facile method to synthesis LDHs based effective antibacterial agents with the potential application in the area of water treatment and antibacterial coating.展开更多
As rice consumption increases,ensuring its safety has become a priority for the food industry.To address this concern,the industry is exploring a single-pass microbial inactivation treatment at the rough rice stage.In...As rice consumption increases,ensuring its safety has become a priority for the food industry.To address this concern,the industry is exploring a single-pass microbial inactivation treatment at the rough rice stage.In this study,a long-grain rice variety,RT7321[21.2%wet basis(WB)and a 20 mm bed thickness]was exposed to microwave radiation(915 MHz frequency)at powers of 16,18,and 20 kW for durations of 1,2,and 3 min.We found that the highest microwave power(20 kW)and the longest exposure duration(3 min)produced the greatest reduction in total aerobic count and total fungal count,reducing them by up to 1.21 and 5.01 log(CFU/g),respectively.Our findings provided insights into the used to high-power,shortduration 915 MHz microwave technology for decontamination purposes in rough rice to help improve the microbial safety of rice.The aim is to develop a single-pass drying approach for microbial inactivation in rice processing facilities while ensuring that the yield and quality is not compromised.展开更多
It is common to observe the epidemic risk perception(ERP)and a decline in subjective well-being(SWB)in the context of public health events,such as Corona Virus Disease 2019(COVID-19).However,there have been few studie...It is common to observe the epidemic risk perception(ERP)and a decline in subjective well-being(SWB)in the context of public health events,such as Corona Virus Disease 2019(COVID-19).However,there have been few studies exploring the impact of individuals’ERP within living space on their SWB,especially from a geographical and daily activity perspective after the resumption of work and other activities following a wave of the pandemic.In this paper,we conducted a study with 789 participants in urban China,measuring their ERP within living space and examining its influence on their SWB using path analysis.The results indicated that individuals’ERP within their living space had a significant negative effect on their SWB.The density of certain types of facilities within their living space,such as bus stops,subway stations,restaurants,fast food shops,convenience shops,hospitals,and public toilets,had a significantly negative impact on their SWB,mediated by their ERP within living space.Additionally,participation in out-of-home work and other activities not only increased individuals’ERP within living space,but also strengthened its negative effect on their SWB.展开更多
基金National Natural Science Foundation of China(Grant No.21975227)the Found of National defence Science and Technology Key Laboratory (Grant No.6142602210306)。
文摘Fe/N-based biomass porous carbon composite(Fe/N-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/N-p Carbon on the thermal decomposition of energetic molecular perovskite-based material DAP-4 was studied.Biomass porous carbonaceous materials was considered as the micro/nano support layers for in situ deposition of Fe/N precursors.Fe/Np Carbon was prepared simply by the high-temperature carbonization method.It was found that it showed the inherent catalysis properties for thermal decomposition of DAP-4.The heat release of DAP-4/Fe/N-p Carbon by DSC curves tested had increased slightly,compared from DAP-4/Fe/N-p Carbon-0.The decomposition temperature peak of DAP-4 at the presence of Fe/N-p Carbon had reduced by 79°C from384.4°C(pure DAP-4) to 305.4°C(DAP-4/Fe/N-p Carbon-3).The apparent activation energy of DAP-4thermal decomposition also had decreased by 29.1 J/mol.The possible catalytic decomposition mechanism of DAP-4 with Fe/N-p Carbon was proposed.
文摘(a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of poly-BLG at variable DP;(d)Reaction rates of LiHMDS and hexylamine initiated BLGNCA polymerization in THF with NCA:initiator ratio of 100∶1 and initial NCA concentration at 0.2 mol/L;(e)CD spectra of poly-BLG at variable DP prepared from LiHMDS-initiated NCA polymerization.
文摘Monodispersed dihydrated zinc oxalate(ZnC_2O_4·2H_2O) particles with characteristic morphology were synthesized by aging a mixed solution of zinc nitrate(Zn(NO_3)_2) and sodium oxalate(Na_2C_2O_4) in the presence of a citrate ligand, with an average flat size of approximately 10–15 μm. The important parameters, including the solution pH values and the concentration of the zinc ions and citrate ligand, were investigated using a series of experiments. It is verified that the citrate ligand significantly affects the morphology of zinc oxalate particles, probably via its multiple roles of chelating, dispersing, and selective absorption. Thermodynamic equilibrium of the distribution of zinc species in an aqueous solution of Zn(Ⅱ)-citrate-oxalate-H_2O was estimated to explain the experimental results and to clarify the size and morphological evolution mechanism of the precipitated particles.
文摘A praedcal opthesis of trans-3,4-aiol derivatives of subnituted chromans via epoxidation with combined use of mangenese (III) salen complex 3 and hydrgen perokide has been developed. These diol derivatives are key intermediates for the syntheis of a series of biologicallimportant chroman compounds.
文摘Nitroalkanes react smoothly with CF3CCl2COCH=CHPh via Michael addition in the presence of inorganic bases such as KF/Al2O3 or K2CO3, giving fluorinecontaining γ-nitro ketones in good yields.
文摘In a facile procedure, 2-(1, 3-dithian-2-ylidene)-l-arylketones 1 vere reduced with magnesium in methanol to give α-aryl-β-(1, 3-dithane) alcohols 2 in good to high yields.
文摘Plumbagic acid[β-(2,3-dihydroxybenzoyl)butyric acid](1),hasbeen synthesized from commcrcially available catechol by two facile routeswith overall yields of 18.6% and 53.5%,rcspectively.
文摘The attractive and impertan complexes, manganese porphyrin aromatic thiolates, are prepared directly by the reaction of chloro(5, 10, 15, 20-tetraphenylporphyrinato) manganese Mn(TPP)Cl with PhSNa and (p-NO2)PhSNa under extremely simple and mild reaction
文摘Air-stable cationic organobismuth complexes (2-5) possessing both acidic and basic characters were synthesized. The catalyst system that comprises an air-stable bifunctional Lewis acidic/basic organobismuth complex and [Bmim]BF4 showed high catalytic activity, diastereoselec-tivity, stability, and reusability in the one-pot synthesis of (E)-α,β-unsaturat-ed ketones through highly selective crossed-condensation of ketones and aldehydes. Through switching the reaction from homogeneous to heterogeneous, the system shows facile separation ability and facile reusability.
基金This work was financially supported by the Program for Interdisciplinary Direction Team in Zhongyuan University of Technology,China.We are grateful for financial support from the Starting Research Fund from the Zhongyuan University of Technology.
文摘of main observation and conclusion Magnetic hydrogels have found extensive applications in fields such as soft robotics,drug delivery and shape morphing.Here a facile method was fabricated to prepare polysaccharide-based magnetic hydrogels.The chitosan-Fe3O4 ferrofluid was obtained by dispersing carboxyl groups modified Fe3O4 nanoparticles uniformly in chitosan matrix.Subsequently,the magnetic polysaccharide hydrogel was obtained by simply mixing cellulose acetoacetate solution with chitosan-Fe3O4 ferrofluid.The structures and properties of the magnetic hydrogel were analyzed using Fourier-transform infrared spectroscopy,rheological recovery,responsiveness,and stability measurements.The results indicated that magnetic polysaccharide hydrogel showed pH responsiveness and excellent self-healing properties,and the hydrogel manifested outstanding stability under physiological conditions(37℃)for 72 h.In addition,the injectable polysaccharide-based hydrogel exhibited sensitive magnetic responsive and shape-shifting ability under an external magnetic field.Therefore,the strategy for the facile preparation of the magnetic polysaccharide-based hydrogel in this work could provide a benign and versatile method for achieving self-healing,responsive,injectable properties for the application in biomedical fields.
基金financially supported by Advance Queensland Research Fellowship Project and Chinese Scholarship Council(CSC)。
文摘Mg2+in MgAl-layered double hydroxides nanoparticles was substituted with different divalent transition metal ions(MAl-LDHs,M:Mg2+,Cu2+,Ni2+,Co2+,and Mn2+)via a facile method to be used as antibacterial agents.The phase structural and morphological characterizations of MAl-LDHs were investigated by XRD,FTIR spectroscopy and TEM.The results have shown that all of MAl-LDHs had typical layered structures except MnAl-LDH which contained Mn304 phases.Particular morphology of MnAl-LDH with ellipsoids,spherical and rod-like structure and CuAl-LDH with rod-like shape existed.IC50(the concentrations providing 50%antibacterial activity)values of CuAl-LDH,NiAl-LDH,CoAl-LDH,and MnAlLDH in broth dilution tests were^800-1500μg/mL.Dosages of CuAl-LDH,CoAl-LDH,and MnAl-LDH with>10 mm inhibition zone in disk diffusion tests were^150-300μg/disk.Antibacterial mechanism of MAl-LDHs may be attributed to the synergistic factors including effected surroundings,surface interactions,morphology of particles,ROS and metal ions.The results indicate a facile method to synthesis LDHs based effective antibacterial agents with the potential application in the area of water treatment and antibacterial coating.
基金supported, in part, by the United States Department of Agriculture National Institute of Food and Agriculture Hatch Act Fundingthe University of Arkansas Grain and Rice Processing Program, USA
文摘As rice consumption increases,ensuring its safety has become a priority for the food industry.To address this concern,the industry is exploring a single-pass microbial inactivation treatment at the rough rice stage.In this study,a long-grain rice variety,RT7321[21.2%wet basis(WB)and a 20 mm bed thickness]was exposed to microwave radiation(915 MHz frequency)at powers of 16,18,and 20 kW for durations of 1,2,and 3 min.We found that the highest microwave power(20 kW)and the longest exposure duration(3 min)produced the greatest reduction in total aerobic count and total fungal count,reducing them by up to 1.21 and 5.01 log(CFU/g),respectively.Our findings provided insights into the used to high-power,shortduration 915 MHz microwave technology for decontamination purposes in rough rice to help improve the microbial safety of rice.The aim is to develop a single-pass drying approach for microbial inactivation in rice processing facilities while ensuring that the yield and quality is not compromised.
基金Under the auspices of the National Natural Science Foundation of China(No.42271234,42101246,42101223)Hong Kong Research Grants Council General Research Fund Grant(No.14605920,14611621,14606922)+1 种基金Hong Kong Research Grants Council Collaborative Research Fund Grant(No.C4023-20GF)Hong Kong Research Grants Council Research Matching Grants RMG(No.8601219,8601242)。
文摘It is common to observe the epidemic risk perception(ERP)and a decline in subjective well-being(SWB)in the context of public health events,such as Corona Virus Disease 2019(COVID-19).However,there have been few studies exploring the impact of individuals’ERP within living space on their SWB,especially from a geographical and daily activity perspective after the resumption of work and other activities following a wave of the pandemic.In this paper,we conducted a study with 789 participants in urban China,measuring their ERP within living space and examining its influence on their SWB using path analysis.The results indicated that individuals’ERP within their living space had a significant negative effect on their SWB.The density of certain types of facilities within their living space,such as bus stops,subway stations,restaurants,fast food shops,convenience shops,hospitals,and public toilets,had a significantly negative impact on their SWB,mediated by their ERP within living space.Additionally,participation in out-of-home work and other activities not only increased individuals’ERP within living space,but also strengthened its negative effect on their SWB.