The catalytic conversion of CO2 to CO via a reverse water gas shift(RWGS)reaction followed by well-established synthesis gas conversion technologies may provide a potential approach to convert CO2 to valuable chemical...The catalytic conversion of CO2 to CO via a reverse water gas shift(RWGS)reaction followed by well-established synthesis gas conversion technologies may provide a potential approach to convert CO2 to valuable chemicals and fuels.However,this reaction is mildly endothermic and competed by a strongly exothermic CO2 methanation reaction at low temperatures.Therefore,the improvement in the low-temperature activities and selectivity of the RWGS reaction is a key challenge for catalyst designs.We reviewed recent advances in the design strategies of supported metal catalysts for enhancing the activity of CO2 conversion and its selectivity to CO.These strategies include varying support,tuning metal–support interactions,adding reducible transition metal oxide promoters,forming bimetallic alloys,adding alkali metals,and enveloping metal particles.These advances suggest that enhancing CO2 adsorption and facilitating CO desorption are key factors to enhance CO2 conversion and CO selectivity.This short review may provide insights into future RWGS catalyst designs and optimization.展开更多
AIM: To study persistence and replication of hepatitis C virus (HCV) in patients' peripheral blood mononuclear cells (PBMC) cultured in vitro. METHODS: Epstein Barr virus (EBV) was used to transform the hepatitis ...AIM: To study persistence and replication of hepatitis C virus (HCV) in patients' peripheral blood mononuclear cells (PBMC) cultured in vitro. METHODS: Epstein Barr virus (EBV) was used to transform the hepatitis C virus from a HCV positive patient to permanent lymphoblastoid cell lines (LCL). Positive and negative HCV RNA strands of the cultured cells and growth media were detected by reverse transcriptase-polymerase chain reaction (RT-PCR) each month. Core and NS5 proteins of HCV were further tested using immunohistochemical SP method and in situ RT-PCR. RESULTS: HCV RNA positive strands were consistently detected the cultured cells for one year. The negative-strand RNA in LCL cells and the positive-strand RNA in supernatants were observed intermittently. Immunohistochemical results medicated expression of HCV NS3 and C proteins in LCL cytoplasm mostly. The positive signal of PCR product was dark blue and mainly localized to the LCL cytoplasm. The RT-PCR signal was eliminated by overnight RNase digestion but not DNase digestion. CONCLUSION: HCV may exist and remain functional in a cultured cell line for a long period.展开更多
BACKGROUND Mental health is one of the important dimensions of health,while depression is an important indicator of mental health evaluation.AIM To investigate the association between intergenerational emotional suppo...BACKGROUND Mental health is one of the important dimensions of health,while depression is an important indicator of mental health evaluation.AIM To investigate the association between intergenerational emotional support and depression of non-cohabiting parents(≥45 years old)in China.METHODS We used the fourth wave data from the China Health and Retirement Longitudinal Study(2015).The data was made up of ten main modules,the associated two datasets,and five constructed datasets.The first step is to select the corresponding module data according to the purpose of this study.Moreover,the data of the six modules are integrated by the unique ID code and we choose depression and non-cohabiting items as the selection conditions.4810 samples were selected,which mainly included data on intergenerational emotional support and the individual scores on depressive symptoms.RESULTS The average age of 4810 respondents was(60.56±14.613)years old.Females were accounted for more than half of the samples(52.6%).74.0%respondents from rural areas and approximately 63.3%of the participants had a chronic disease.The mean value of the CESD-10 score was 13.06(SD5.225).Both faces to face and phone contacts were protective factors on depression symptoms in the mid-aged and seniors in China(P<0.05).In terms of the frequency of face to face contact,the more frequently you met your parents,the lower your parents'depressive score was.Also,phone contact variable results are displayed as a positive correlation completely between inter-generational contacts from children and depressive symptoms in non-cohabiting parents in China.Children’s education level and income level were also reducing the risk of depression in noncohabiting parents.However,gender,children’s numerous,chronic disease and chronic disease number were the risk factors.CONCLUSION Intergenerational emotional support is associated with depressive symptoms in non-cohabiting parents in China.However,the relationship was also affected by other variables.展开更多
Porous ceramics usually require high mechanical strength and maximized porosity simultaneously,while for conventional particle grading strategies,it is highly challenging to meet both demands.To this end,a reverse par...Porous ceramics usually require high mechanical strength and maximized porosity simultaneously,while for conventional particle grading strategies,it is highly challenging to meet both demands.To this end,a reverse particle grading strategy was developed based on the linear packing model by unusually introducing coarse particles(d_(50)=16μm)into a fine particle(d50=5μm)matrix.Following the extrusion and sintering process,tubular porous SiC ceramic supports with improved mechanical strength were successfully fabricated.The effects of coarse particles on the rheological properties of the ceramic paste and the macroscopic properties and microstructure of the SiC supports were systematically investigated.With an increase in the content of coarse SiC particles to 30 wt%,the pressure generated during extrusion decreased from 5.5±0.2 to 1.3±0.1 MPa.Notably,the bending strength of the tubular supports increased from 36.6±5.6 to 49.1±4.5 MPa when 20 wt%coarse powder was incorporated.The notably improved mechanical strength was attributed to the distribution of coarse particles that prolonged the route of crack deflection.Additionally,the optimized tubular supports had an average pore size of 1.2±0.1μm,an open porosity of 45.1%±1.6%,and a water permeability of 7163±150 L/(m^(2)·h·bar)as well as good alkali and acid corrosion resistance.Significantly,the strategy was proven to be feasible for the scale-up fabrication of 19-channel SiC tubular porous ceramic supports.展开更多
Metal-support interaction(MSI)is regarded as an indispensable manner to stabilize active metals and modulate catalytic activity,which shows great potentials in developing of efficient hydrogen evolution reaction(HER)e...Metal-support interaction(MSI)is regarded as an indispensable manner to stabilize active metals and modulate catalytic activity,which shows great potentials in developing of efficient hydrogen evolution reaction(HER)electrode with high activity and strong robustness.Herein,this work presents a novel heterostructure with ultrafine platinum quantum dots(Pt QDs)on defective catalytic supports derived from metal-organic frameworks(MOFs).It is indicated substantial oxygen vacancies can be generated and Pt–Pt bonds can be optimized through topological transformation.The resulting Pt/T-NiFe-BDC(BDC:C8H6O4)exhibits competitive HER activity in alkaline seawater,attaining ultralow overpotentials of 158 and 266 mV at 500 and 1000 mA cm^(-2)with fast kinetics and outstanding stability.An asymmetric water electrolyzer using Pt/T-NiFe-BDC as a cathode only requires a voltage of 1.89 V to generate an industrial density of 1000 mA cm^(-2)and shows no attenuation in 500-h continuous test at 500 mA cm^(-2).Theoretical calculations and in-situ spectroscopic analysis reveal the reversible hydrogen spillover mechanism,in which oxygen vacancies facilitate the sluggish water dissociation and Pt QDs promote the H^(*)combination.This study provides a new paradigm to engineer metal-supported catalysts for efficient and robust seawater splitting.展开更多
The reverse water−gas shift(RWGS)reaction is a key process for CO_(2) conversion and sustainable fuel production,yet the nature of the active sites on Pt/TiO_(2) cluster catalysts remains elusive.Using first-principle...The reverse water−gas shift(RWGS)reaction is a key process for CO_(2) conversion and sustainable fuel production,yet the nature of the active sites on Pt/TiO_(2) cluster catalysts remains elusive.Using first-principles microkinetic simulations,we systematically investigated the catalytic behavior of Pt clusters on TiO_(2) under operational reaction conditions.We studied three distinct catalytic sites-Pt cluster surfaces,oxygen vacancies(O_(V))on TiO_(2),and Pt−O_(V)−Ti interfaces-and revealed that the Pt−O_(V)−Ti interface exhibited the highest RWGS activity via a redox mechanism.This synergy enhances CO_(2) activation and facilitates oxygen reduction more effectively than the isolated O_(V) on TiO_(2),which show 4-fold lower activity.In contrast,CO-covered Pt clusters show minimal CO_(2) activation but serve as H2 dissociation sites,enabling hydrogen spillover to adjacent O_(V) on TiO_(2),thereby sustaining the RWGS process.Kinetic analysis revealed OH reduction to H2O as the rate-determining step on both interfacial Pt−O_(V)−Ti and at the O_(V) on the TiO_(2)−X support.These findings highlight the pivotal role of the Pt−O_(V)−Ti interface in driving the RWGS and offer a design strategy for optimizing high-temperature CO_(2) hydrogenation catalysts by maximizing the number of interfacial active sites.展开更多
基金the National Key Research and Development Program of China(No.2016YFB0600900)the National Natural Science Foundation of China(Nos.21676194 and 21873067)for their support。
文摘The catalytic conversion of CO2 to CO via a reverse water gas shift(RWGS)reaction followed by well-established synthesis gas conversion technologies may provide a potential approach to convert CO2 to valuable chemicals and fuels.However,this reaction is mildly endothermic and competed by a strongly exothermic CO2 methanation reaction at low temperatures.Therefore,the improvement in the low-temperature activities and selectivity of the RWGS reaction is a key challenge for catalyst designs.We reviewed recent advances in the design strategies of supported metal catalysts for enhancing the activity of CO2 conversion and its selectivity to CO.These strategies include varying support,tuning metal–support interactions,adding reducible transition metal oxide promoters,forming bimetallic alloys,adding alkali metals,and enveloping metal particles.These advances suggest that enhancing CO2 adsorption and facilitating CO desorption are key factors to enhance CO2 conversion and CO selectivity.This short review may provide insights into future RWGS catalyst designs and optimization.
基金The paper was support by a grant from the Ministry Youth Research of China,No.98-1-269
文摘AIM: To study persistence and replication of hepatitis C virus (HCV) in patients' peripheral blood mononuclear cells (PBMC) cultured in vitro. METHODS: Epstein Barr virus (EBV) was used to transform the hepatitis C virus from a HCV positive patient to permanent lymphoblastoid cell lines (LCL). Positive and negative HCV RNA strands of the cultured cells and growth media were detected by reverse transcriptase-polymerase chain reaction (RT-PCR) each month. Core and NS5 proteins of HCV were further tested using immunohistochemical SP method and in situ RT-PCR. RESULTS: HCV RNA positive strands were consistently detected the cultured cells for one year. The negative-strand RNA in LCL cells and the positive-strand RNA in supernatants were observed intermittently. Immunohistochemical results medicated expression of HCV NS3 and C proteins in LCL cytoplasm mostly. The positive signal of PCR product was dark blue and mainly localized to the LCL cytoplasm. The RT-PCR signal was eliminated by overnight RNase digestion but not DNase digestion. CONCLUSION: HCV may exist and remain functional in a cultured cell line for a long period.
文摘BACKGROUND Mental health is one of the important dimensions of health,while depression is an important indicator of mental health evaluation.AIM To investigate the association between intergenerational emotional support and depression of non-cohabiting parents(≥45 years old)in China.METHODS We used the fourth wave data from the China Health and Retirement Longitudinal Study(2015).The data was made up of ten main modules,the associated two datasets,and five constructed datasets.The first step is to select the corresponding module data according to the purpose of this study.Moreover,the data of the six modules are integrated by the unique ID code and we choose depression and non-cohabiting items as the selection conditions.4810 samples were selected,which mainly included data on intergenerational emotional support and the individual scores on depressive symptoms.RESULTS The average age of 4810 respondents was(60.56±14.613)years old.Females were accounted for more than half of the samples(52.6%).74.0%respondents from rural areas and approximately 63.3%of the participants had a chronic disease.The mean value of the CESD-10 score was 13.06(SD5.225).Both faces to face and phone contacts were protective factors on depression symptoms in the mid-aged and seniors in China(P<0.05).In terms of the frequency of face to face contact,the more frequently you met your parents,the lower your parents'depressive score was.Also,phone contact variable results are displayed as a positive correlation completely between inter-generational contacts from children and depressive symptoms in non-cohabiting parents in China.Children’s education level and income level were also reducing the risk of depression in noncohabiting parents.However,gender,children’s numerous,chronic disease and chronic disease number were the risk factors.CONCLUSION Intergenerational emotional support is associated with depressive symptoms in non-cohabiting parents in China.However,the relationship was also affected by other variables.
基金the financial support provided by the National Key R&D Program of China(No.2022YFB3805002)the National Natural Science Foundation of China(No.22308150)+5 种基金Jiangsu Provincial Department of Science and Technology(No.BK20232010)the Research Programs of the Science and Technology of Guangxi Zhuang Autonomous Region(No.GUIKE-AA22117015-1)the Natural Science Foundation of Jiangsu Province(No.BK20220345)the Key R&D Program of Jiangsu Province(No.BE2023360)the Key R&D Project of Nanjing Jiangbei New Area(No.ZDYF202203)the Youth Science and Technology Talents Lifting Project of Jiangsu Association of Science and Technology(No.105019ZS_007).
文摘Porous ceramics usually require high mechanical strength and maximized porosity simultaneously,while for conventional particle grading strategies,it is highly challenging to meet both demands.To this end,a reverse particle grading strategy was developed based on the linear packing model by unusually introducing coarse particles(d_(50)=16μm)into a fine particle(d50=5μm)matrix.Following the extrusion and sintering process,tubular porous SiC ceramic supports with improved mechanical strength were successfully fabricated.The effects of coarse particles on the rheological properties of the ceramic paste and the macroscopic properties and microstructure of the SiC supports were systematically investigated.With an increase in the content of coarse SiC particles to 30 wt%,the pressure generated during extrusion decreased from 5.5±0.2 to 1.3±0.1 MPa.Notably,the bending strength of the tubular supports increased from 36.6±5.6 to 49.1±4.5 MPa when 20 wt%coarse powder was incorporated.The notably improved mechanical strength was attributed to the distribution of coarse particles that prolonged the route of crack deflection.Additionally,the optimized tubular supports had an average pore size of 1.2±0.1μm,an open porosity of 45.1%±1.6%,and a water permeability of 7163±150 L/(m^(2)·h·bar)as well as good alkali and acid corrosion resistance.Significantly,the strategy was proven to be feasible for the scale-up fabrication of 19-channel SiC tubular porous ceramic supports.
文摘Metal-support interaction(MSI)is regarded as an indispensable manner to stabilize active metals and modulate catalytic activity,which shows great potentials in developing of efficient hydrogen evolution reaction(HER)electrode with high activity and strong robustness.Herein,this work presents a novel heterostructure with ultrafine platinum quantum dots(Pt QDs)on defective catalytic supports derived from metal-organic frameworks(MOFs).It is indicated substantial oxygen vacancies can be generated and Pt–Pt bonds can be optimized through topological transformation.The resulting Pt/T-NiFe-BDC(BDC:C8H6O4)exhibits competitive HER activity in alkaline seawater,attaining ultralow overpotentials of 158 and 266 mV at 500 and 1000 mA cm^(-2)with fast kinetics and outstanding stability.An asymmetric water electrolyzer using Pt/T-NiFe-BDC as a cathode only requires a voltage of 1.89 V to generate an industrial density of 1000 mA cm^(-2)and shows no attenuation in 500-h continuous test at 500 mA cm^(-2).Theoretical calculations and in-situ spectroscopic analysis reveal the reversible hydrogen spillover mechanism,in which oxygen vacancies facilitate the sluggish water dissociation and Pt QDs promote the H^(*)combination.This study provides a new paradigm to engineer metal-supported catalysts for efficient and robust seawater splitting.
基金supported by the Key Technologies R&D Program of China(2021YFA1502804)the Strategic Priority Research Program of the Chinese Academy of Science(XDB0450102)+2 种基金the National Natural Science Foundation of China(22172150,22222306,22221003,and 22432004)the Innovation Program for Quantum Science and Technology(2021ZD0303302)the high-performance computational resources provided by the University of Science and Technology of China and Hefei Advanced Computing Center。
文摘The reverse water−gas shift(RWGS)reaction is a key process for CO_(2) conversion and sustainable fuel production,yet the nature of the active sites on Pt/TiO_(2) cluster catalysts remains elusive.Using first-principles microkinetic simulations,we systematically investigated the catalytic behavior of Pt clusters on TiO_(2) under operational reaction conditions.We studied three distinct catalytic sites-Pt cluster surfaces,oxygen vacancies(O_(V))on TiO_(2),and Pt−O_(V)−Ti interfaces-and revealed that the Pt−O_(V)−Ti interface exhibited the highest RWGS activity via a redox mechanism.This synergy enhances CO_(2) activation and facilitates oxygen reduction more effectively than the isolated O_(V) on TiO_(2),which show 4-fold lower activity.In contrast,CO-covered Pt clusters show minimal CO_(2) activation but serve as H2 dissociation sites,enabling hydrogen spillover to adjacent O_(V) on TiO_(2),thereby sustaining the RWGS process.Kinetic analysis revealed OH reduction to H2O as the rate-determining step on both interfacial Pt−O_(V)−Ti and at the O_(V) on the TiO_(2)−X support.These findings highlight the pivotal role of the Pt−O_(V)−Ti interface in driving the RWGS and offer a design strategy for optimizing high-temperature CO_(2) hydrogenation catalysts by maximizing the number of interfacial active sites.
