Shrinkage-induced cracking is a common issue in concrete structures,where the formation of cracks not only affects the aesthetic appearance of concrete but also potentially reduces its durability and strength.In this ...Shrinkage-induced cracking is a common issue in concrete structures,where the formation of cracks not only affects the aesthetic appearance of concrete but also potentially reduces its durability and strength.In this study,the effect of ceramsite sand addition on the properties of a ternary system of cement-ground granulated blast furnace slag(GGBFS)-phosphogypsum(PG)is investigated.In particular,the fluidity,rheology,hydration heat,compressive strength,autogenous shrinkage,and drying shrinkage of the considered mortar specimens are analyzed.The results indicate that an increase in PG content leads to a decrease in fluidity,higher viscosity,lower exothermic peak,and lower compressive strength.However,the shrinkage of the mortar specimens is effectively compensated.The incorporation of internal curing water from ceramsite sand improves fluidity,decreases both yield stress and viscosity,enhances the degree of hydration,and induces mortar expansion.However,the inferior mechanical properties of the ceramsite sand generally produce a decrease in the compressive strength.展开更多
Copy-Move Forgery Detection(CMFD)is a technique that is designed to identify image tampering and locate suspicious areas.However,the practicality of the CMFD is impeded by the scarcity of datasets,inadequate quality a...Copy-Move Forgery Detection(CMFD)is a technique that is designed to identify image tampering and locate suspicious areas.However,the practicality of the CMFD is impeded by the scarcity of datasets,inadequate quality and quantity,and a narrow range of applicable tasks.These limitations significantly restrict the capacity and applicability of CMFD.To overcome the limitations of existing methods,a novel solution called IMTNet is proposed for CMFD by employing a feature decoupling approach.Firstly,this study formulates the objective task and network relationship as an optimization problem using transfer learning.Furthermore,it thoroughly discusses and analyzes the relationship between CMFD and deep network architecture by employing ResNet-50 during the optimization solving phase.Secondly,a quantitative comparison between fine-tuning and feature decoupling is conducted to evaluate the degree of similarity between the image classification and CMFD domains by the enhanced ResNet-50.Finally,suspicious regions are localized using a feature pyramid network with bottom-up path augmentation.Experimental results demonstrate that IMTNet achieves faster convergence,shorter training times,and favorable generalization performance compared to existingmethods.Moreover,it is shown that IMTNet significantly outperforms fine-tuning based approaches in terms of accuracy and F_(1).展开更多
Air pollution has posed a serious public health issue in China. In the study, we aimed to examine the burden of air pollution and its association with climate factors and total mortality. City-level daily air quality ...Air pollution has posed a serious public health issue in China. In the study, we aimed to examine the burden of air pollution and its association with climate factors and total mortality. City-level daily air quality index (AQI) data in 161 cities of China in 2014, and meteorological factors, socioeconomic status and total morality were obtained from China environmental, meteor-ology and healthcare agencies. Linear regression, spatial autocorrelation analysis and panel fixed models were applied in data analysis. Among 161 cities, monthly average AQI was significantly different by seasons and regions. The highest average AQI was in winter, and the lowest in summer. A significant clustering distribution of AQI by cities was observed, with the highest AQI in north China (22 cities, mean = 117.36). Among the 161 cities, 5 cities (3%) had AQI > 150 (e.g., moderate polluted reference value), and 50 cities (31.1%) had AQI between 100 and 150 (slightly polluted value). Daily heat index, precipitation and sunshine hours were negatively and significantly, but air pressure was positively correlated with AQI. Cities with higher AQI concentrations had higher total mortality than those with lower AQI. This AQI-mortality association remained significant after adjustment for socioeconomic status. In conclusion, the study highlights the burden and seasonal, regional and areas variations in air pollution across the nation. Air pollution is estimated to account for more than 4% of the urban health inequality in total mortality in China.展开更多
Vanadium redox flow batteries(VRFBs)are widely applied in energy storage systems(e.g.,wind energy,solar energy),while the poor activity of commonly used carbon-based electrode limits their large-scale application.In t...Vanadium redox flow batteries(VRFBs)are widely applied in energy storage systems(e.g.,wind energy,solar energy),while the poor activity of commonly used carbon-based electrode limits their large-scale application.In this study,the graphene modified carbon felt(G/CF)with a large area of 20 cm×20 cm has been successfully prepared by a chemical vapor deposition(CVD)strategy,achieving outstanding electrocatalytic redox reversibility of the VRFBs.The decorating graphene can provide abundant active sites for the vanadium redox reactions.Compared with the pristine carbon felt(CF)electrode,the G/CF composite electrode possesses more defective sites on surface,which enhances activity toward VO^(2+)/VO^(2+)couple and electrochemical performances.For instance,such G/CF electrode delivered remarkable voltage efficiency(VE)of 88.4%and energy efficiency(EE)of 86.4%at 100 mA·cm^(-2),much higher than CF electrode by 2.1%and 3.78%,respectively.The long-term cycling stability of G/CF electrode was further investigated and a high retention value of 47.6%can be achieved over 600 cycles.It is demonstrated that this work develops a promising and effective strategy to synthesize the large size of carbon electrode with high performances for the next-generation VRFBs.展开更多
Conductive hydrogels have become one of the most promising candidates for flexible electronics due to their excellent mechanical flexibility,durability of deformation,and good electrical conductivity.However,in real a...Conductive hydrogels have become one of the most promising candidates for flexible electronics due to their excellent mechanical flexibility,durability of deformation,and good electrical conductivity.However,in real applications,severe environments occur frequently,such as extremely cold weather.General hydrogels always lack anti-freeze and anti-dehydration abilities.Consequently,the functions of electronic devices based on traditional hydrogels will quickly fail in extreme environments.Therefore,the development of environmentally robust hydrogels that can withstand extremely low temperatures,overcome dehydration,and ensure the stable operation of electronic devices has become increasingly important.Here,we report a kind of graphene oxide(GO)incorporated polyvinyl alcohol-polyacrylamide(PVA-PAAm)double network hydrogel(GPPDhydrogel)which shows excellent anti-freeze ability.The GPPD-hydrogel exhibits not only good flexibility and ultra-high stretchability up to 2,000%,but ensures a high sensitivity when used as the strain sensor at−50°C.More importantly,when serving as the electrode of a sandwich-structural triboelectric nanogenerator(TENG),the GPPD-hydrogel endows the TENG high and stable output performances even under−80°C.Besides,the GPPD-hydrogel is demonstrated long-lasting moisture retention over 100 days.The GPPD-hydrogel provides a reliable and promising candidate for the new generation of wearable electronics.展开更多
Computer vision techniques are real-time,immersive,and perceptual human-computer interaction technology.Excellent display effect,dynamic surface flexibility,and safe bio-adhesion are essential for various human–compu...Computer vision techniques are real-time,immersive,and perceptual human-computer interaction technology.Excellent display effect,dynamic surface flexibility,and safe bio-adhesion are essential for various human–computer interaction applications,such as metaverse interfaces,skin-like sensors,and optoelectronic medical devices.However,realizing the flexible matching of inorganic optoelectronic devices and organisms remains a grand challenge for current display technologies.Here,we proposed a novel strategy by combining the optoelectronic advantages of inorganic micro light emitting diode(micro-LED)display and the extraordinary mechanical/biological compatibility of organic materials to overcome this challenge.A highly elastic(greater than 2000%strain),highly transparent(94%visible light transmittance),biocompatible conductive hydrogel composite electrode layer was fabricated.For the first time,we realized the on-chip electrical interconnection of 4900 LED units to form a blue-green light display patch with high resolution(264 PPI),low power consumption(4.4 mW)and adaptive surface attachment.This work demonstrates an integrated scheme and potential applications of flexible high-resolution microdisplays,such as wearable fullcolor micro-LED smart curved display devices and conformable biomedical monitoring systems.展开更多
Based on inexpensive,safe,and environmentally friendly active redox species,neutral polysulfide-ferrocyanide redox flow batteries(PFRFBs)have attracted much attention for large-scale energy storage.However,the develop...Based on inexpensive,safe,and environmentally friendly active redox species,neutral polysulfide-ferrocyanide redox flow batteries(PFRFBs)have attracted much attention for large-scale energy storage.However,the development of PFRFBs is undermined by the expensive commercial membrane materials as well as the sluggish polysulfide redox reactions.This work attempts to solve these critical problems by combining the economical membrane with the highly catalytic electrode.In specific,K^(+)-exchanged sulfonated polyether ether ketone(SPEEK-K)membranes have been investigated in PFRFBs to replace the costly Nafion membrane.SPEEK-K with optimized degree of sulfonation enables the PFRFB high average coulombic efficiency of 99.80%and superior energy efficiency of 90.42%at a current density of 20mAcm^(-2).Meanwhile,to overcome the kinetic limitations of polysulfide redox reactions,a CuS-modified carbon felt electrode is demonstrated with excellent catalytic performance,enabling the PFRFB higher and more stable energy efficiency over cycling.The combination of the cost-effective membrane with the catalytic electrode in one cell leads to a capacity retention of 99.54%after 1180 cycles and an outstanding power density(up to 223mWcm^(-2)).The significant enhancements of electrochemical performance at reduced capital cost will make the PFRFB more promising for large-scale energy storage systems.展开更多
Stereoscopic microscopy is a promising technology to obtain three-dimensional microscopic images.Such microscopes are based on the parallax effect,and as such require two lenses to focus at two different points.Geomet...Stereoscopic microscopy is a promising technology to obtain three-dimensional microscopic images.Such microscopes are based on the parallax effect,and as such require two lenses to focus at two different points.Geometrical constraints,however,restrict their numerical apertures to about 0.2,thus limiting the system’s resolution.Higher numerical apertures(.35)can be achieved with designs using only one bulk lens,but such systems are0 times more costly than the conventional ones.Thus,there is a pressing need for alternative solutions to improve the resolution of stereoscopic systems.Here,we show that high-resolution and low-cost stereoscopic systems can be obtained using birefringent single-layer metalenses.We design and fabricate a birefringent metalens operating at 532 nm with a numerical aperture as high as 0.4.The metalens is then used to demonstrate high-resolution stereoscopic imaging of biological samples.The microscopic images are further displayed and perceived vividly in an autostereoscopic display.Our demonstration paves the way to a new strategy to achieve high-resolution and low-cost stereoscopic microscopes.展开更多
We perform detailed quantum chemical calculations to elucidate the origin and mechanism of the selective permeability of alkali and alkaline earth cation- decorated graphene oxide (M-GO) membranes to organic solvent...We perform detailed quantum chemical calculations to elucidate the origin and mechanism of the selective permeability of alkali and alkaline earth cation- decorated graphene oxide (M-GO) membranes to organic solvents. The results show that the selectivity is associated mainly with the transport properties of solvents in the membranes, which depends on two regions of the flow path: the sp3 C-O matrix of the GO sheets and the cation at the center of the hexagon rather than the sp~ region. According to the delocalization of ~ states in sp2 regions, we propose a design guide for high-quality M-GO membranes. The solvent-cation interaction essentially causes directional transport of molecules in the M-GO membranes under the transmembrane pressure, indicating a site-to-site mech- anism. The solvent-sp3 C-O matrix interaction may inhibit molecular transport between two fixed cations by consuming energy. The competition between energy consumption by the solvent-cation interaction and energy expenditure by the solvent-sp3 C-O matrix interaction leads to various transport properties of solvents and thus allows for the selective permeability of the M-GO membranes. Findings from the study are helpful for the future design of multifunctional M-GO macro-membranes as cost-effective solution nanofilters in chemical, biological, and medical applications展开更多
Aim:According to the current guidelines,transarterial chemoembolization(TACE)remains the first-line therapies for hepatocellular carcinoma(HCC)patients at Barcelona Clinic Liver Cancer(BCLC)B-stage and sorafenib is a ...Aim:According to the current guidelines,transarterial chemoembolization(TACE)remains the first-line therapies for hepatocellular carcinoma(HCC)patients at Barcelona Clinic Liver Cancer(BCLC)B-stage and sorafenib is a small molecule target drug for BCLC C-stage.In clinical practice,clinicians have attempted to use stereotactic body radiation therapy(SBRT)plus TACE for treating intermediate-to advanced-stage HCC.However,the therapeutic effects are still inconsistent.This meta-analysis was conducted to elucidate the validity and safety of the combination therapy of SBRT plus TACE in the patients with intermediate-to advanced-stage HCC.Methods:PubMed,MEDLINE,Web of Science,China Biology Medicine,Chinese Knowledge resources integrated and Chinese Scientific Journal Full-Text Database was searched from their inception date to November 2018.The survival rates(half-year,one-year and two-year)were analyzed and compared between the observation groups and the control groups.The negative conversion rate of AFP and the total effective rate were also assessed.Risk ratios(RR)and 95%CI were calculated to express therapeutic effects. ;Results:A total of 1,210 patients from 13 eligible studies were included.The cooperation of TACE and SBRT notably ameliorated the whole survival rates of half-year,one-year,two-year,the negative conversion rate of AFP,and the total effective rate,compared with TACE or SBRT monotherapy[RR(the total effective rate),1.412,95%CI:1.309-1.523,P<0.001],[RR(half-year survival rate),1.196,95%CI:1.121-1.276,P<0.001],[RR(one-year survival rate),1.327,95%CI:1.236-1.424,P<0.001],[RR(two-year survival rate),1.479,95%CI:1.284-1.703,P<0.001]and[RR(negative conversion rate of AFP),1.756,95%CI:1.502-2.059,P<0.001].Sensitivity analysis supported the above results.Conclusion:Combination therapy of SBRT and TACE provides survival benefits in intermediate-to advanced-stage HCC patients compared to monotherapy of SBRT or TACE.展开更多
Aim:This meta-analysis was designed to compare the effectiveness of the combination of transarterial chemoembolization(TACE)and radiofrequency ablation(RFA)vs.that of TACE alone in hepatocellular carcinoma(HCC)tumors ...Aim:This meta-analysis was designed to compare the effectiveness of the combination of transarterial chemoembolization(TACE)and radiofrequency ablation(RFA)vs.that of TACE alone in hepatocellular carcinoma(HCC)tumors larger than 5 cm.Methods:PUBMED,CNKI,and CBM were searched for all related randomized controlled trials(RCTs)up until October 22,2018.Eleven studies were identified that compared TACE with RFAvs.TACE alone for HCC treatment.Tumor response rate,the proportion of patients with either complete or partial shrinkage of tumors,and survival rate were the major evaluation indices.Results:Meta-analysis data revealed that TACE with RFA showed significantly better tumor response rate(risk ratio(RR)=1.452,95%confidence interval(CI):1.308-1.610,P<0.001)and 1-year overall survival rate(RR=1.412,95%CI:1.249-1.596,P<0.001)than that of TACE alone treatment.Conclusion:The data of our study indicates that TACE combined with RFA in the treatment of HCC larger than 5 cm is an effective comprehensive interventional therapy.展开更多
Water wave energy exhibits great potential toalleviate the global energy crisis. However, harvesting andutilizing wave energy are challenging due to its irregularity,randomness, and low frequency. Triboelectric nanoge...Water wave energy exhibits great potential toalleviate the global energy crisis. However, harvesting andutilizing wave energy are challenging due to its irregularity,randomness, and low frequency. Triboelectric nanogenerators(TENGs) have gained significant attention for harvesting waveenergy with high efficiency. This study presents a novelellipsoidal, pendulum-like TENG integrating both liquid-liquid(L-L) and solid-solid (S-S) triboelectricity (LS-TENG). Thisinnovative design enables continuous wave energy harvestingand self-powered marine environment monitoring under variousconditions, including temperature, humidity, and light intensity. The binary immiscible liquids within the LS-TENG’s innersoft balloon create dynamic, and self-adjustable L-L contact interfaces, significantly increasing the L-L contact area andenhancing L-L contact electrification (CE). The unique self-adaptive, soft S-S contact increases the S-S contact areacompared to traditional hard point contact, better adapting to the irregular movements of waves and promoting efficient S-SCE. The LS-TENG achieves highly efficient wave energy harvesting by coupling L-L and S-S CE. Furthermore, the uniquesoft contact design protects the S-S interfaces from mechanical wear and damage during long-term work. The LS-TENG’snovel structure provides an innovative and effective way for water wave energy harvesting.展开更多
基金funded by the China Railway Major Bridge Engineering Group Co.,Ltd.,Project(2023-48-Key Project).
文摘Shrinkage-induced cracking is a common issue in concrete structures,where the formation of cracks not only affects the aesthetic appearance of concrete but also potentially reduces its durability and strength.In this study,the effect of ceramsite sand addition on the properties of a ternary system of cement-ground granulated blast furnace slag(GGBFS)-phosphogypsum(PG)is investigated.In particular,the fluidity,rheology,hydration heat,compressive strength,autogenous shrinkage,and drying shrinkage of the considered mortar specimens are analyzed.The results indicate that an increase in PG content leads to a decrease in fluidity,higher viscosity,lower exothermic peak,and lower compressive strength.However,the shrinkage of the mortar specimens is effectively compensated.The incorporation of internal curing water from ceramsite sand improves fluidity,decreases both yield stress and viscosity,enhances the degree of hydration,and induces mortar expansion.However,the inferior mechanical properties of the ceramsite sand generally produce a decrease in the compressive strength.
基金supported and founded by the Guizhou Provincial Science and Technology Project under the Grant No.QKH-Basic-ZK[2021]YB311the Youth Science and Technology Talent Growth Project of Guizhou Provincial Education Department under Grant No.QJH-KY-ZK[2021]132+2 种基金the Guizhou Provincial Science and Technology Project under the Grant No.QKH-Basic-ZK[2021]YB319the National Natural Science Foundation of China(NSFC)under Grant 61902085the Key Laboratory Program of Blockchain and Fintech of Department of Education of Guizhou Province(2023-014).
文摘Copy-Move Forgery Detection(CMFD)is a technique that is designed to identify image tampering and locate suspicious areas.However,the practicality of the CMFD is impeded by the scarcity of datasets,inadequate quality and quantity,and a narrow range of applicable tasks.These limitations significantly restrict the capacity and applicability of CMFD.To overcome the limitations of existing methods,a novel solution called IMTNet is proposed for CMFD by employing a feature decoupling approach.Firstly,this study formulates the objective task and network relationship as an optimization problem using transfer learning.Furthermore,it thoroughly discusses and analyzes the relationship between CMFD and deep network architecture by employing ResNet-50 during the optimization solving phase.Secondly,a quantitative comparison between fine-tuning and feature decoupling is conducted to evaluate the degree of similarity between the image classification and CMFD domains by the enhanced ResNet-50.Finally,suspicious regions are localized using a feature pyramid network with bottom-up path augmentation.Experimental results demonstrate that IMTNet achieves faster convergence,shorter training times,and favorable generalization performance compared to existingmethods.Moreover,it is shown that IMTNet significantly outperforms fine-tuning based approaches in terms of accuracy and F_(1).
文摘Air pollution has posed a serious public health issue in China. In the study, we aimed to examine the burden of air pollution and its association with climate factors and total mortality. City-level daily air quality index (AQI) data in 161 cities of China in 2014, and meteorological factors, socioeconomic status and total morality were obtained from China environmental, meteor-ology and healthcare agencies. Linear regression, spatial autocorrelation analysis and panel fixed models were applied in data analysis. Among 161 cities, monthly average AQI was significantly different by seasons and regions. The highest average AQI was in winter, and the lowest in summer. A significant clustering distribution of AQI by cities was observed, with the highest AQI in north China (22 cities, mean = 117.36). Among the 161 cities, 5 cities (3%) had AQI > 150 (e.g., moderate polluted reference value), and 50 cities (31.1%) had AQI between 100 and 150 (slightly polluted value). Daily heat index, precipitation and sunshine hours were negatively and significantly, but air pressure was positively correlated with AQI. Cities with higher AQI concentrations had higher total mortality than those with lower AQI. This AQI-mortality association remained significant after adjustment for socioeconomic status. In conclusion, the study highlights the burden and seasonal, regional and areas variations in air pollution across the nation. Air pollution is estimated to account for more than 4% of the urban health inequality in total mortality in China.
基金the financial support from the 100 Talented Team of Hunan Province(XiangZu[2016]91)the“Huxiang high-level talents”program(Nos.2018RS3077,2019RS1007,and 2019RS1046)+1 种基金the National Natural Science Foundation of China(No.52002405)the Open Fund of National Engineering Laboratory of Highway Maintenance Technology(Changsha University of Science&Technology)(No.kfj170105).
文摘Vanadium redox flow batteries(VRFBs)are widely applied in energy storage systems(e.g.,wind energy,solar energy),while the poor activity of commonly used carbon-based electrode limits their large-scale application.In this study,the graphene modified carbon felt(G/CF)with a large area of 20 cm×20 cm has been successfully prepared by a chemical vapor deposition(CVD)strategy,achieving outstanding electrocatalytic redox reversibility of the VRFBs.The decorating graphene can provide abundant active sites for the vanadium redox reactions.Compared with the pristine carbon felt(CF)electrode,the G/CF composite electrode possesses more defective sites on surface,which enhances activity toward VO^(2+)/VO^(2+)couple and electrochemical performances.For instance,such G/CF electrode delivered remarkable voltage efficiency(VE)of 88.4%and energy efficiency(EE)of 86.4%at 100 mA·cm^(-2),much higher than CF electrode by 2.1%and 3.78%,respectively.The long-term cycling stability of G/CF electrode was further investigated and a high retention value of 47.6%can be achieved over 600 cycles.It is demonstrated that this work develops a promising and effective strategy to synthesize the large size of carbon electrode with high performances for the next-generation VRFBs.
基金support from the National Natural Science Foundation of China(Nos.22001018,52192610,52173298,and 61904012)the National Key R&D Program of China(No.2021YFA1201603).
文摘Conductive hydrogels have become one of the most promising candidates for flexible electronics due to their excellent mechanical flexibility,durability of deformation,and good electrical conductivity.However,in real applications,severe environments occur frequently,such as extremely cold weather.General hydrogels always lack anti-freeze and anti-dehydration abilities.Consequently,the functions of electronic devices based on traditional hydrogels will quickly fail in extreme environments.Therefore,the development of environmentally robust hydrogels that can withstand extremely low temperatures,overcome dehydration,and ensure the stable operation of electronic devices has become increasingly important.Here,we report a kind of graphene oxide(GO)incorporated polyvinyl alcohol-polyacrylamide(PVA-PAAm)double network hydrogel(GPPDhydrogel)which shows excellent anti-freeze ability.The GPPD-hydrogel exhibits not only good flexibility and ultra-high stretchability up to 2,000%,but ensures a high sensitivity when used as the strain sensor at−50°C.More importantly,when serving as the electrode of a sandwich-structural triboelectric nanogenerator(TENG),the GPPD-hydrogel endows the TENG high and stable output performances even under−80°C.Besides,the GPPD-hydrogel is demonstrated long-lasting moisture retention over 100 days.The GPPD-hydrogel provides a reliable and promising candidate for the new generation of wearable electronics.
基金The authors thank for the support from the National Natural Science Foundation of China(Nos.52173298,61904012,and 52192611)the National Key R&D Program of China(No.2021YFA1201603)the Fundamental Research Funds for the Central Universities.
文摘Computer vision techniques are real-time,immersive,and perceptual human-computer interaction technology.Excellent display effect,dynamic surface flexibility,and safe bio-adhesion are essential for various human–computer interaction applications,such as metaverse interfaces,skin-like sensors,and optoelectronic medical devices.However,realizing the flexible matching of inorganic optoelectronic devices and organisms remains a grand challenge for current display technologies.Here,we proposed a novel strategy by combining the optoelectronic advantages of inorganic micro light emitting diode(micro-LED)display and the extraordinary mechanical/biological compatibility of organic materials to overcome this challenge.A highly elastic(greater than 2000%strain),highly transparent(94%visible light transmittance),biocompatible conductive hydrogel composite electrode layer was fabricated.For the first time,we realized the on-chip electrical interconnection of 4900 LED units to form a blue-green light display patch with high resolution(264 PPI),low power consumption(4.4 mW)and adaptive surface attachment.This work demonstrates an integrated scheme and potential applications of flexible high-resolution microdisplays,such as wearable fullcolor micro-LED smart curved display devices and conformable biomedical monitoring systems.
基金We acknowledge financial support from the 100 Talented Team of Hunan Province(XiangZu[2016]91)the“Huxiang High-Level Talents”program(2019RS1046 and 2018RS3077)+2 种基金the Open Fund of National Engineering Laboratory of Highway Maintenance Technology(Changsha University of Science and Technology)(kfj170105)the Natural Science Foundation of Hunan Province(2020JJ5566)the Outstanding Young Talent Project of Education Department of Hunan Province(19B029).
文摘Based on inexpensive,safe,and environmentally friendly active redox species,neutral polysulfide-ferrocyanide redox flow batteries(PFRFBs)have attracted much attention for large-scale energy storage.However,the development of PFRFBs is undermined by the expensive commercial membrane materials as well as the sluggish polysulfide redox reactions.This work attempts to solve these critical problems by combining the economical membrane with the highly catalytic electrode.In specific,K^(+)-exchanged sulfonated polyether ether ketone(SPEEK-K)membranes have been investigated in PFRFBs to replace the costly Nafion membrane.SPEEK-K with optimized degree of sulfonation enables the PFRFB high average coulombic efficiency of 99.80%and superior energy efficiency of 90.42%at a current density of 20mAcm^(-2).Meanwhile,to overcome the kinetic limitations of polysulfide redox reactions,a CuS-modified carbon felt electrode is demonstrated with excellent catalytic performance,enabling the PFRFB higher and more stable energy efficiency over cycling.The combination of the cost-effective membrane with the catalytic electrode in one cell leads to a capacity retention of 99.54%after 1180 cycles and an outstanding power density(up to 223mWcm^(-2)).The significant enhancements of electrochemical performance at reduced capital cost will make the PFRFB more promising for large-scale energy storage systems.
基金National Key Research and Development Program of China(2020YFC2007102)National Natural Science Foundation of China(11704421,11974436,12074444)+3 种基金Basic and Applied Basic Research Foundation of Guangdong Province(2020A1515011184,2020B1515020019)Innovation Group Project of Southern Marine Science and Engineering(Guangdong)Sao Paulo Research Foundation FAPESP(2020/00619-4,2021/06121-0)CNPq(307602/2021-4)。
文摘Stereoscopic microscopy is a promising technology to obtain three-dimensional microscopic images.Such microscopes are based on the parallax effect,and as such require two lenses to focus at two different points.Geometrical constraints,however,restrict their numerical apertures to about 0.2,thus limiting the system’s resolution.Higher numerical apertures(.35)can be achieved with designs using only one bulk lens,but such systems are0 times more costly than the conventional ones.Thus,there is a pressing need for alternative solutions to improve the resolution of stereoscopic systems.Here,we show that high-resolution and low-cost stereoscopic systems can be obtained using birefringent single-layer metalenses.We design and fabricate a birefringent metalens operating at 532 nm with a numerical aperture as high as 0.4.The metalens is then used to demonstrate high-resolution stereoscopic imaging of biological samples.The microscopic images are further displayed and perceived vividly in an autostereoscopic display.Our demonstration paves the way to a new strategy to achieve high-resolution and low-cost stereoscopic microscopes.
文摘We perform detailed quantum chemical calculations to elucidate the origin and mechanism of the selective permeability of alkali and alkaline earth cation- decorated graphene oxide (M-GO) membranes to organic solvents. The results show that the selectivity is associated mainly with the transport properties of solvents in the membranes, which depends on two regions of the flow path: the sp3 C-O matrix of the GO sheets and the cation at the center of the hexagon rather than the sp~ region. According to the delocalization of ~ states in sp2 regions, we propose a design guide for high-quality M-GO membranes. The solvent-cation interaction essentially causes directional transport of molecules in the M-GO membranes under the transmembrane pressure, indicating a site-to-site mech- anism. The solvent-sp3 C-O matrix interaction may inhibit molecular transport between two fixed cations by consuming energy. The competition between energy consumption by the solvent-cation interaction and energy expenditure by the solvent-sp3 C-O matrix interaction leads to various transport properties of solvents and thus allows for the selective permeability of the M-GO membranes. Findings from the study are helpful for the future design of multifunctional M-GO macro-membranes as cost-effective solution nanofilters in chemical, biological, and medical applications
基金This study was funded by the National Natural Science Foundations of China(81773488,81172287).
文摘Aim:According to the current guidelines,transarterial chemoembolization(TACE)remains the first-line therapies for hepatocellular carcinoma(HCC)patients at Barcelona Clinic Liver Cancer(BCLC)B-stage and sorafenib is a small molecule target drug for BCLC C-stage.In clinical practice,clinicians have attempted to use stereotactic body radiation therapy(SBRT)plus TACE for treating intermediate-to advanced-stage HCC.However,the therapeutic effects are still inconsistent.This meta-analysis was conducted to elucidate the validity and safety of the combination therapy of SBRT plus TACE in the patients with intermediate-to advanced-stage HCC.Methods:PubMed,MEDLINE,Web of Science,China Biology Medicine,Chinese Knowledge resources integrated and Chinese Scientific Journal Full-Text Database was searched from their inception date to November 2018.The survival rates(half-year,one-year and two-year)were analyzed and compared between the observation groups and the control groups.The negative conversion rate of AFP and the total effective rate were also assessed.Risk ratios(RR)and 95%CI were calculated to express therapeutic effects. ;Results:A total of 1,210 patients from 13 eligible studies were included.The cooperation of TACE and SBRT notably ameliorated the whole survival rates of half-year,one-year,two-year,the negative conversion rate of AFP,and the total effective rate,compared with TACE or SBRT monotherapy[RR(the total effective rate),1.412,95%CI:1.309-1.523,P<0.001],[RR(half-year survival rate),1.196,95%CI:1.121-1.276,P<0.001],[RR(one-year survival rate),1.327,95%CI:1.236-1.424,P<0.001],[RR(two-year survival rate),1.479,95%CI:1.284-1.703,P<0.001]and[RR(negative conversion rate of AFP),1.756,95%CI:1.502-2.059,P<0.001].Sensitivity analysis supported the above results.Conclusion:Combination therapy of SBRT and TACE provides survival benefits in intermediate-to advanced-stage HCC patients compared to monotherapy of SBRT or TACE.
基金This study was funded by National Natural Science Foundations of China(81773488 and 8177110260).
文摘Aim:This meta-analysis was designed to compare the effectiveness of the combination of transarterial chemoembolization(TACE)and radiofrequency ablation(RFA)vs.that of TACE alone in hepatocellular carcinoma(HCC)tumors larger than 5 cm.Methods:PUBMED,CNKI,and CBM were searched for all related randomized controlled trials(RCTs)up until October 22,2018.Eleven studies were identified that compared TACE with RFAvs.TACE alone for HCC treatment.Tumor response rate,the proportion of patients with either complete or partial shrinkage of tumors,and survival rate were the major evaluation indices.Results:Meta-analysis data revealed that TACE with RFA showed significantly better tumor response rate(risk ratio(RR)=1.452,95%confidence interval(CI):1.308-1.610,P<0.001)and 1-year overall survival rate(RR=1.412,95%CI:1.249-1.596,P<0.001)than that of TACE alone treatment.Conclusion:The data of our study indicates that TACE combined with RFA in the treatment of HCC larger than 5 cm is an effective comprehensive interventional therapy.
基金support from the National Natural Science Foundation of China(Nos.52173298 and 52192611)the National Key R&D Project from Minister of Science and Technology(No.2021YFA1201603)+1 种基金Beijing Natural Science Foundation(No.Z230024)the Fundamental Research Funds for the Central Universities.
文摘Water wave energy exhibits great potential toalleviate the global energy crisis. However, harvesting andutilizing wave energy are challenging due to its irregularity,randomness, and low frequency. Triboelectric nanogenerators(TENGs) have gained significant attention for harvesting waveenergy with high efficiency. This study presents a novelellipsoidal, pendulum-like TENG integrating both liquid-liquid(L-L) and solid-solid (S-S) triboelectricity (LS-TENG). Thisinnovative design enables continuous wave energy harvestingand self-powered marine environment monitoring under variousconditions, including temperature, humidity, and light intensity. The binary immiscible liquids within the LS-TENG’s innersoft balloon create dynamic, and self-adjustable L-L contact interfaces, significantly increasing the L-L contact area andenhancing L-L contact electrification (CE). The unique self-adaptive, soft S-S contact increases the S-S contact areacompared to traditional hard point contact, better adapting to the irregular movements of waves and promoting efficient S-SCE. The LS-TENG achieves highly efficient wave energy harvesting by coupling L-L and S-S CE. Furthermore, the uniquesoft contact design protects the S-S interfaces from mechanical wear and damage during long-term work. The LS-TENG’snovel structure provides an innovative and effective way for water wave energy harvesting.