Flexible sensors,a class of devices that can convert external mechanical or physical signals into changes in resistance,capacitance,or current,have developed rapidly since the concept was first proposed.Due to the spe...Flexible sensors,a class of devices that can convert external mechanical or physical signals into changes in resistance,capacitance,or current,have developed rapidly since the concept was first proposed.Due to the special properties and naturally occurring excellent microstructures of biomaterials,it can provide more desirable properties to flexible devices.This paper systematically discusses the commonly used biomaterials for bio-based flexible devices in current research applications and their deployment in preparing flexible sensors with different mechanisms.According to the characteristics of other properties and application requirements of biomaterials,the mechanisms of their functional group properties,special microstructures,and bonding interactions in the context of various sensing applications are presented in detail.The practical application scenarios of biomaterial-based flexible devices are highlighted,including human-computer interactions,energy harvesting,wound healing,and related biomedical applications.Finally,this paper also reviews in detail the limitations of biobased materials in the construction of flexible devices and presents challenges and trends in the development of biobased flexible sensors,as well as to better explore the properties of biomaterials to ensure functional synergy within the composite materials.展开更多
Foundation models(FMs)have rapidly evolved and have achieved signicant accomplishments in computer vision tasks.Specically,the prompt mechanism conveniently allows users to integrate image prior information into the m...Foundation models(FMs)have rapidly evolved and have achieved signicant accomplishments in computer vision tasks.Specically,the prompt mechanism conveniently allows users to integrate image prior information into the model,making it possible to apply models without any training.Therefore,we proposed a workflow based on foundation models and zero training to solve the tasks of photoacoustic(PA)image processing.We employed the Segment Anything Model(SAM)by setting simple prompts and integrating the model's outputs with prior knowledge of the imaged objects to accomplish various tasks,including:(1)removing the skin signal in three-dimensional PA image rendering;(2)dual speed-of-sound reconstruction,and(3)segmentation ofnger blood vessels.Through these demonstrations,we have concluded that FMs can be directly applied in PA imaging without the requirement for network design and training.This potentially allows for a hands-on,convenient approach to achieving efficient and accurate segmentation of PA images.This paper serves as a comprehensive tutorial,facilitating the mastery of the technique through the provision of code and sample datasets.展开更多
The original online version of this article was revised:In this article,Jianhua Fan and Junqiu Zhang are both corresponding authors.In this article Junqiu Zhang should have been denoted as a corresponding author,as we...The original online version of this article was revised:In this article,Jianhua Fan and Junqiu Zhang are both corresponding authors.In this article Junqiu Zhang should have been denoted as a corresponding author,as well.The original article has been corrected.展开更多
Lightweight and high-toughness carbon fiber/phenolic ablator(CFPA)is required as the Thermal Protection System(TPS)material of aerospace vehicles for next-generation space missions.To improve the ablative properties,s...Lightweight and high-toughness carbon fiber/phenolic ablator(CFPA)is required as the Thermal Protection System(TPS)material of aerospace vehicles for next-generation space missions.To improve the ablative properties,silica sol with good particle size distribution prepared using tetramethoxysilane(TMOS)was blended with natural rubber latex and deposited onto carbon fiber felt,which was then integrated with phenolic aerogel matrix,introducing nano-silica into the framework of CFPA.The modified CFPA with a low density of 0.28—0.31 g/cm3exhibits strain-in-fracture as high as 31.2%and thermal conductivity as low as 0.054 W/(m·K).Furthermore,a trace amount of nano-silica could effectively protect CFPA from erosion of oxidizing atmosphere in different high-temperature environments.The oxyacetylene ablation test of 3000°C for 20 s shows a mass ablation rate of 0.0225 g/s,a linear ablation rate of 0.209 mm/s for the modified CFPA,which are 9.64%and 24.82%lower than the unmodified one.Besides,the long-time butane ablation test of 1200°C for 200 s shows an insignificant recession with mass and linear ablation rate of 0.079 g/s and 0.039 mm/s,16.84%and 13.33%lower than the unmodified one.Meanwhile,the fixed thermocouple in the test also demonstrates a good thermal insulation performance with a low peak back-face temperature of 207.7°C,12.25%lower than the unmodified one.Therefore,the nano-silica modified CFPA with excellent overall performance presents promising prospects in high-temperature aerospace applications.展开更多
As a traditional Chinese herbal medicine,Schisandrae Chinensis Fructus(SC)has been used in medicine and food industry due to its health care and therapeutic effects.Over the past 20 years,the use of SC and its active ...As a traditional Chinese herbal medicine,Schisandrae Chinensis Fructus(SC)has been used in medicine and food industry due to its health care and therapeutic effects.Over the past 20 years,the use of SC and its active ingredient lignans in the prevention and treatment of liver diseases has been increasing,and their hepatoprotective effects has increased the interest of the public and academia.Therefore,in the present work,we first determined the effectiveness of SC in the treatment of liver diseases such as metabolic associated fatty liver disease,alcoholic liver disease,cholestatic liver disease and acute liver injury.Subsequently,the pharmacological effects and molecular mechanisms of lignans,the active components of SC,for liver disease treatment were comprehensively summarized for the first time.The results showed that the lignans in SC could achieve hepatoprotective effects by regulating lipid metabolism,anti-fibrosis,anti-inflammation,anti-oxidation,anti-tumor and regulating bile acid metabolism.The mechanism mainly involved adenosine 5’-monophosphate-activated protein kinase,endoplasmic reticulum stress,sterol regulatory element binding protein 1c,autophagy,transforming growth factor-β,mitogen-activated protein kinase,microRNA,nuclear factor kappa-B,nuclear factor erythroid-2-related factor 2,heat shock proteins and pregnane X receptor signaling pathways.These results can lay a scientific foundation for the development of hepatoprotective drugs or functional foods from SC/lignans.展开更多
Lithium-sulfur(Li-S)batteries are regarded as the most formidable competitor to lithium-ion batteries due to their superior theoretical capacity.However,the negative impact of soluble lithium polysulfide(LiPSs)and slo...Lithium-sulfur(Li-S)batteries are regarded as the most formidable competitor to lithium-ion batteries due to their superior theoretical capacity.However,the negative impact of soluble lithium polysulfide(LiPSs)and slow redox reaction kinetics seriously hamper the commercialization of Li-S batteries.In this study,a defect-rich single-atom catalyst with an oversaturated asymmetric Fe-N_(5)coordination structure anchored in defective g-C_(3)N_(4)(C_(3)N_(4)-Fe@rGO)is designed via an absorption-pyrolysis strategy.The two-dimensional(2D)conducting C_(3)N_(4)@graphene structure with abundant defect sites accelerates the trans-fer and transportation of lithium ions and electrons.The oversaturated asymmetric Fe-N_(5)coordination structure effectively improves the adsorbility of LiPSs and accelerates the redox kinetics of sulfur species.Hence,the Li-S cell with a C_(3)N_(4)-Fe@rGO modified separator reveals a high initial capacity(1197.1 mAh g^(-1) at 0.2 C)and a low capacity decay rate(0.037%per cycle after 900 cycles at 1 C).Even at high sulfur loading and extreme temperatures of 0℃,it also shows good cycling performance.This work creates ideas for synthesizing oversaturated single-atom coordination environments and an efficient route to the practical realization of the Li-S batteries.展开更多
The polysulfides shuttle effect,sluggish sulfur redox kinetics and the corrosion of the Li anode have become important factors limiting the commercial application of lithium-sulfur batteries(LSBs).Herein,the polyoxome...The polysulfides shuttle effect,sluggish sulfur redox kinetics and the corrosion of the Li anode have become important factors limiting the commercial application of lithium-sulfur batteries(LSBs).Herein,the polyoxometalate(POM)nanoclusters with high catalytic activity and cobalt selenide with strong polarity are initially complemented to construct a PMo_(12)/CoSe_(2)@NC/CNTs multifunctional separator that can simultaneously solve the above problems.A series of experimental and theoretical results demonstrate that the Keggin-type POM,H_(3)PMo_(12)O_(40)nH_(2)O(PMo_(12))nanoclusters could function as catalytic centers for sulfur-involved transformations,with the CoSe_(2)nanoparticles serving as adsorption sites for soluble polysulfides.Accordingly,the assembled battery with the PMo_(12)/CoSe_(2)@NC/CNTs modified separator achieves an initial discharge capacity of 1263.79 mA h g^(-1),maintaining 635.77 mA h g^(-1),with a capacity decay rate of 0.06%per cycle after 500 cycles at 3C.This work provides a strategic approach for incorporating POM nanoclusters with polar periodic nanomaterials in LSB separators,contributing to the development of multifunctional separator materials,thus promoting the advancement of energy storage systems.展开更多
Optical-resolution photoacoustic microscopy is a novel imaging technique that combines the advantages of optical and ultrasound imaging,enabling high-resolution visualization of biological tissues at the micrometer sc...Optical-resolution photoacoustic microscopy is a novel imaging technique that combines the advantages of optical and ultrasound imaging,enabling high-resolution visualization of biological tissues at the micrometer scale.However,the divergence of the excited Gaussian beam limits the depth-of-field of the system to less than 100μm,which hinders accurate three-dimensional imaging of living tissues and restrictsits applicability in biological research.Therefore,there is an urgent need for an effective method to enhance the depth-of-field without altering the hardware configuration.This paper presents a photoacoustic microscopy depth-of-field extension method and system based on three-dimensional continuity and sparsity deconvolution.This method utilizes a depth-varying point spread function and incorporates continuity and sparsity con-straints into the deconvolution process to mitigate the effect of background noise,enhancing the stability and accuracy of the depth-of-field extension.Experimental results using tungsten wire phantoms suggest that the depth-of-field of system can be extended to 650 pm,which is 7.2 times greater than conventional system,while improving the resolution of the defocused region by an average factor of 3.5.Furthermore,experiments on zebrafish and nude mouse ears with irregular topologies demonstrate that the proposed method successfully overcomes image blurring and the loss of structural information due to limited depth-of-field.All the results suggest that the system with higher lateral resolution and enhanced depth-of-field has significant potential for a wide range of practical biomedical applications.展开更多
Stress corrosion cracking(SCC) of an SA508-309 L/308 L–316 L dissimilar metal weld joint in primary pressurized water reactor environment was investigated by the interrupted slow strain rate tension tests following a...Stress corrosion cracking(SCC) of an SA508-309 L/308 L–316 L dissimilar metal weld joint in primary pressurized water reactor environment was investigated by the interrupted slow strain rate tension tests following a microstructure characterization. The 308 L weld metal shows a higher content of δ ferrite than the 309 L weld metal. In addition, no obvious Cr-depletion but carbides precipitation at δ phase boundaries was observed in both 308 L and 309 L weld metals. The slow strain rate tension tests showed that the SCC susceptibility of the base and weld metals of the dissimilar metal weld joint follows the order of SA508 < 308 L weld metal < the heat affected zone of 316 L base metal < 309 L weld metal.The higher SCC susceptibility of 309 L weld metal than that of 308 L weld metal is likely due to the lower content of δ ferrite. In addition, a preferential SCC initiation in the 309 L weld metal adjacent to 308 L weld metal is attributed to few carbides in this region.展开更多
As a crucial signaling molecule, calcium plays a critical role in many physiological and pathological processes by regulating ion channel activity. Recently, one study resolved the structure of the transient receptor ...As a crucial signaling molecule, calcium plays a critical role in many physiological and pathological processes by regulating ion channel activity. Recently, one study resolved the structure of the transient receptor potential melastatin 2(TRPM2) channel from Nematostella vectensis(nvTRPM2). This identified a calcium-binding site in the S2–S3 loop, while its effect on channel gating remains unclear. Here, we investigated the role of this calcium-binding site in both nvTRPM2 and human TRPM2(hTRPM2) by mutagenesis and patch-clamp recording. Unlike hTRPM2, nvT RPM2 cannot be activated by calcium alone. Moreover, the inactivation rate of nvTRPM2 was decreased as intracellular calcium concentration was increased. In addition, our results showed that the four key residues in the calcium-binding site of S2–S3 loop have similar effects on the gating processes of nvTRPM2 and hTRPM2. Among them, the mutations at negatively charged residues(glutamate and aspartate) substantially decreased the currents of nvT RPM2 and hTRPM2. This suggests that these sites are essential for calcium-dependent channel gating. For the charge-neutralizing residues(glutamine and asparagine) in the calcium-binding site, our data showed that glutamine mutating to alanine or glutamate did not affect the channel activity, but glutamine mutating to lysine caused loss of function. Asparagine mutating to aspartate still remained functional, while asparagine mutating to alanine or lysine led to little channel activity. These results suggest that the side chain of glutamine has a less contribution to channel gating than does asparagine. However, our data indicated that both glutamine mutating to alanine or glutamate and asparagine mutating to aspartate accelerated the channel inactivation rate, suggesting that the calcium-binding site in the S2–S3 loop is important for calcium-dependent channel inactivation. Taken together, our results uncovered the effect of four key residues in the S2–S3 loop of TRPM2 on the TRPM2 gating process.展开更多
Potassium-selenium(K-Se)batteries have attracted more and more attention because of their high theoretical specific capacity and natural abundance of K resources.However,dissolution of polyselenides,large volume expan...Potassium-selenium(K-Se)batteries have attracted more and more attention because of their high theoretical specific capacity and natural abundance of K resources.However,dissolution of polyselenides,large volume expansion during cycling and low utilization of Se remain great challenges,leading to poor rate capability and cycle life.Herein,N/O dual-doped carbon nanofibers with interconnected micro/mesopores(MMCFs)are designed as hosts to manipulate Se molecular configuration for advanced flexible K-Se batteries.The micropores play a role in confining small Se molecule(Se_(2–3)),which could inhibit the formation of polyselenides and work as physical barrier to stabilize the cycle performance.While the mesopores can confine long-chain Se(Se_(4–7)),promising sufficient Se loading and contributing to higher discharge voltage of the whole Se@MMCFs composite.The N/O co-doping and the 3D interpenetrating nanostructure improve electrical conductivity and keep the structure integrity after cycling.The obtained Se_(2–3)/Se_(4–7)@MMCFs electrode exhibits an unprecedented cycle life(395 mA h g^(−1) at 1 A g^(−1) after 2000 cycles)and high specific energy density(400 Wh kg^(−1),nearly twice the specific energy density of the Se_(2–3)@MMCFs).This study offers a rational design for the realization of a high energy density and long cycle life chalcogen cathode for energy storage.展开更多
We present a high-performance terahertz(THz)radiation source based on the photon-activated charge domain(PACD)quenched mode of GaAs photoconductive antennas(GaAs PCA).The THz radiation characteristics of the GaAs PCA ...We present a high-performance terahertz(THz)radiation source based on the photon-activated charge domain(PACD)quenched mode of GaAs photoconductive antennas(GaAs PCA).The THz radiation characteristics of the GaAs PCA under different operating modes are studied.Compared with the linear mode,the intensity of THz wave radiated by the GaAs PCA can be greatly enhanced due to the avalanche multiplication effect of carriers in the PACD quenched mode.The results show that when the carrier multiplication ratio is 16.92,the peak-to-peak value of THz field radiated in the PACD quenched mode increases by as much as about 4.19 times compared to the maximum values in the linear mode.展开更多
Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commerciali...Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commercialization almost all exhibit low Na-ion conductivities of around 10^(-5)S cm^(-1)or lower.Here,we report a chloride solid electrolyte,Na_(2.7)ZFCl_(5.3)O_(0.7),which reaches a Na-ion conductivity of 2.29×10^(-4)S cm^(-1)at 25℃without involving overly expensive raw materials such as rare-earth chlorides or Na_(2)S.In addition to the efficient ion transport,Na_(2.7)ZrCl_(5.3)O_(0.7)also shows an excellent deformability surpassing that of the widely studied Na_(3)PS_(4),Na_(3)SbS_(4),and Na_(2)ZrCl_(6)solid electrolytes.The combination of these advantages allows the all-solid-state cell based on Na_(2.7)ZrCl_(5.3)O_(0.7)and NaCrO_(2)to realize stable room-temperature cycling at a much higher specific current than those based on other non-viscoelastic chloride solid electrolytes in literature(120 mA g^(-1)vs.12-55 mA g^(-1));after 100 cycles at such a high rate,the Na_(2.7)ZFCl_(5.3)O_(0.7)-based cell can still deliver a discharge capacity of 80 mAh g^(-1)at25℃.展开更多
Antiferromagnetism has become a promising candidate for the next generation electronic devices due to its thermal stability,low energy consumption,and fast switching speed.However,the canceling of the net magnetic mom...Antiferromagnetism has become a promising candidate for the next generation electronic devices due to its thermal stability,low energy consumption,and fast switching speed.However,the canceling of the net magnetic moment in antiferromagnetic order presents great challenge on quantitative characterization and modulation,hindering its investigation and application.In this work,utilizing the optical second harmonic generation(SHG)in a wide temperature range,the integrated differential phase contrast scanning transmission electron microscopy,and firstprinciples calculations,we performed a quantitative study on the evolution of non-collinear antiferromagnetic order in BiFeO_(3)films with a series of strains.We found that the antiferromagnetic coupling was significantly enhanced,featured by the increase of Néel temperature from 428 K to 646 K,and by one order of enhancement of SHG intensity contributed from the G-type antiferromagnetic order by strain manipulation from-2.4%to+0.6%.We attributed the enhancement of the antiferromagnetic coupling to the enhancement of the superexchange interaction as the Fe-O-Fe bond angle approaches 180°when the in-plane lattice constants increase,which might also result in a tendency from a non-collinear antiferromagnetic order to a collinear one.Our work not only bridges the antiferromagnetic order and the strain manipulation in epitaxial multiferroics,more importantly,also paves a way for quantitative characterization by SHG technology and the precise manipulation of antiferromagnetism.展开更多
The commercialization of lithium-sulfur(Li-S)batteries has been struggling due to the uncontrollable shuttle effect and slow polysulfides redox kinetics.Single atom alloys(SAAs)with the advantages of single-atom and n...The commercialization of lithium-sulfur(Li-S)batteries has been struggling due to the uncontrollable shuttle effect and slow polysulfides redox kinetics.Single atom alloys(SAAs)with the advantages of single-atom and nanoparticle catalysts are still rarely studied in the field of Li-S batteries.Herein,a NiCo_(SAA)was supported on MXene(NiCo_(SAA)-MXene),which served as the cascade electrocatalyst for improving the Li^(+)desolvation and polysulfides conversion kinetics.In this design,the special structure of the single atom alloy can fully inhibit the mutual stacking of MXene and achieve good stability,while the MXene nanosheet serves as support to enable the uniform dispersion of single atom alloy with ultra-small particle size,facilitating maximum atom utilization.Moreover,the electron cloud of Co was redistributed with the assistance of Ni,resulting in an enhanced electrocatalytic performance,as confirmed by theoretical calculations.At the cascade catalysis of NiCo_(SAA)-MXene,more free Li^(+)was released,and the diffusion of Li^(+)was enhanced to participate in the polysulfides redox reaction,effectively inhibiting the shuttle effect of polysulfides,as proved by in-situ/ex-situ Raman and electrochemical characterization.As a result,the Li-S battery with NiCo_(SAA)-MXene modified separator achieved a reversible capacity of 992 mAh·g^(-1)at 0.2 C after 100 cycles and a superior rate capability of 746 mAh·g^(-1)at 4 C.At a high sulfur loading of 4.7 mg·cm^(-2),the Li-S battery also maintains an excellent cycling stability(100 cycles,3.1 mAh·cm^(-2)),demonstrating significant promise for commercial applications.展开更多
Microstructure of the heat affected zone （HAZ） of a 308L-316L stainless steel （SS） weld joint and its corrosion behavior in high temperature water were studied. Peak of the residual strain was observed to approach...Microstructure of the heat affected zone （HAZ） of a 308L-316L stainless steel （SS） weld joint and its corrosion behavior in high temperature water were studied. Peak of the residual strain was observed to approach to the fusion boundary in the HAZ while the strain increased from the top to root areas of the HAZ. The root area of the HAZ shows a lower corrosion resistance in high temperature water than the top and middle areas of the HAZ. This is attributed to a higher level of residual strain in association with a higher density of tangled dislocations in the top area of the HAZ. The results suggest that the residual strain in the HAZ could also promote the SCC through its effect on corrosion, in addition to that on the local microstructure and mechanical property of the steel.展开更多
基金supported financially by the National Natural Science Foundation of China(52205308,22208120)the China Postdoctoral Science Foundation(2022M711300).
文摘Flexible sensors,a class of devices that can convert external mechanical or physical signals into changes in resistance,capacitance,or current,have developed rapidly since the concept was first proposed.Due to the special properties and naturally occurring excellent microstructures of biomaterials,it can provide more desirable properties to flexible devices.This paper systematically discusses the commonly used biomaterials for bio-based flexible devices in current research applications and their deployment in preparing flexible sensors with different mechanisms.According to the characteristics of other properties and application requirements of biomaterials,the mechanisms of their functional group properties,special microstructures,and bonding interactions in the context of various sensing applications are presented in detail.The practical application scenarios of biomaterial-based flexible devices are highlighted,including human-computer interactions,energy harvesting,wound healing,and related biomedical applications.Finally,this paper also reviews in detail the limitations of biobased materials in the construction of flexible devices and presents challenges and trends in the development of biobased flexible sensors,as well as to better explore the properties of biomaterials to ensure functional synergy within the composite materials.
基金support from Strategic Project of Precision Surgery,Tsinghua UniversityInitiative Scientific Research Program,Institute for Intelligent Healthcare,Tsinghua University+5 种基金Tsinghua-Foshan Institute of Advanced ManufacturingNational Natural Science Foundation of China(61735016)Beijing Nova Program(20230484308)Young Elite Scientists Sponsorship Program by CAST(2023QNRC001)Youth Elite Program of Beijing Friendship Hospital(YYQCJH2022-9)Science and Technology Program of Beijing Tongzhou District(KJ2023CX012).
文摘Foundation models(FMs)have rapidly evolved and have achieved signicant accomplishments in computer vision tasks.Specically,the prompt mechanism conveniently allows users to integrate image prior information into the model,making it possible to apply models without any training.Therefore,we proposed a workflow based on foundation models and zero training to solve the tasks of photoacoustic(PA)image processing.We employed the Segment Anything Model(SAM)by setting simple prompts and integrating the model's outputs with prior knowledge of the imaged objects to accomplish various tasks,including:(1)removing the skin signal in three-dimensional PA image rendering;(2)dual speed-of-sound reconstruction,and(3)segmentation ofnger blood vessels.Through these demonstrations,we have concluded that FMs can be directly applied in PA imaging without the requirement for network design and training.This potentially allows for a hands-on,convenient approach to achieving efficient and accurate segmentation of PA images.This paper serves as a comprehensive tutorial,facilitating the mastery of the technique through the provision of code and sample datasets.
文摘The original online version of this article was revised:In this article,Jianhua Fan and Junqiu Zhang are both corresponding authors.In this article Junqiu Zhang should have been denoted as a corresponding author,as well.The original article has been corrected.
基金partly supported by the National Natural Science Foundation of China(Grant Nos.22178107,U21A2060,22178116)Xinjiang Uygur Autonomous Region Key Research and Development Program(Grant No.2022B01030)Shanghai Pujiang Program(Grant No.21PJD019)。
文摘Lightweight and high-toughness carbon fiber/phenolic ablator(CFPA)is required as the Thermal Protection System(TPS)material of aerospace vehicles for next-generation space missions.To improve the ablative properties,silica sol with good particle size distribution prepared using tetramethoxysilane(TMOS)was blended with natural rubber latex and deposited onto carbon fiber felt,which was then integrated with phenolic aerogel matrix,introducing nano-silica into the framework of CFPA.The modified CFPA with a low density of 0.28—0.31 g/cm3exhibits strain-in-fracture as high as 31.2%and thermal conductivity as low as 0.054 W/(m·K).Furthermore,a trace amount of nano-silica could effectively protect CFPA from erosion of oxidizing atmosphere in different high-temperature environments.The oxyacetylene ablation test of 3000°C for 20 s shows a mass ablation rate of 0.0225 g/s,a linear ablation rate of 0.209 mm/s for the modified CFPA,which are 9.64%and 24.82%lower than the unmodified one.Besides,the long-time butane ablation test of 1200°C for 200 s shows an insignificant recession with mass and linear ablation rate of 0.079 g/s and 0.039 mm/s,16.84%and 13.33%lower than the unmodified one.Meanwhile,the fixed thermocouple in the test also demonstrates a good thermal insulation performance with a low peak back-face temperature of 207.7°C,12.25%lower than the unmodified one.Therefore,the nano-silica modified CFPA with excellent overall performance presents promising prospects in high-temperature aerospace applications.
基金supported by National Natural Science Foundation of China(81891012,U19A2010,81630101)Sichuan Province Science and Technology Support Program(2021JDRC0041)Innovation Team and Talents Cultivation Program of National Administration of Traditional Chinese Medicine(ZYYCXTD-D-202209).
文摘As a traditional Chinese herbal medicine,Schisandrae Chinensis Fructus(SC)has been used in medicine and food industry due to its health care and therapeutic effects.Over the past 20 years,the use of SC and its active ingredient lignans in the prevention and treatment of liver diseases has been increasing,and their hepatoprotective effects has increased the interest of the public and academia.Therefore,in the present work,we first determined the effectiveness of SC in the treatment of liver diseases such as metabolic associated fatty liver disease,alcoholic liver disease,cholestatic liver disease and acute liver injury.Subsequently,the pharmacological effects and molecular mechanisms of lignans,the active components of SC,for liver disease treatment were comprehensively summarized for the first time.The results showed that the lignans in SC could achieve hepatoprotective effects by regulating lipid metabolism,anti-fibrosis,anti-inflammation,anti-oxidation,anti-tumor and regulating bile acid metabolism.The mechanism mainly involved adenosine 5’-monophosphate-activated protein kinase,endoplasmic reticulum stress,sterol regulatory element binding protein 1c,autophagy,transforming growth factor-β,mitogen-activated protein kinase,microRNA,nuclear factor kappa-B,nuclear factor erythroid-2-related factor 2,heat shock proteins and pregnane X receptor signaling pathways.These results can lay a scientific foundation for the development of hepatoprotective drugs or functional foods from SC/lignans.
基金supported by the National Natural Science Foundation of China(Nos.U21A2060 and 22178116)the Natural Science Foundation of Shanghai(No.22ZR1417400)the Fundamental Research Funds for the Central Universities(Nos.222201817001,50321041918013,JKA01221601,JKD01241701).
文摘Lithium-sulfur(Li-S)batteries are regarded as the most formidable competitor to lithium-ion batteries due to their superior theoretical capacity.However,the negative impact of soluble lithium polysulfide(LiPSs)and slow redox reaction kinetics seriously hamper the commercialization of Li-S batteries.In this study,a defect-rich single-atom catalyst with an oversaturated asymmetric Fe-N_(5)coordination structure anchored in defective g-C_(3)N_(4)(C_(3)N_(4)-Fe@rGO)is designed via an absorption-pyrolysis strategy.The two-dimensional(2D)conducting C_(3)N_(4)@graphene structure with abundant defect sites accelerates the trans-fer and transportation of lithium ions and electrons.The oversaturated asymmetric Fe-N_(5)coordination structure effectively improves the adsorbility of LiPSs and accelerates the redox kinetics of sulfur species.Hence,the Li-S cell with a C_(3)N_(4)-Fe@rGO modified separator reveals a high initial capacity(1197.1 mAh g^(-1) at 0.2 C)and a low capacity decay rate(0.037%per cycle after 900 cycles at 1 C).Even at high sulfur loading and extreme temperatures of 0℃,it also shows good cycling performance.This work creates ideas for synthesizing oversaturated single-atom coordination environments and an efficient route to the practical realization of the Li-S batteries.
基金supported by the National Natural Science Foundation of China(22201244,22374125,21971221 and 21773203)the Yangzhou University Interdisciplinary Research Foundation for Chemistry Discipline of Targeted Support(yzuxk202010)+2 种基金High-Level Entrepreneurial and Innovative Talents Program of Jiangsu‘Qing Lan Project’in Colleges and Universities of Jiangsu ProvinceLvyangjinfeng Talent Program of Yangzhou,China Postdoctoral Science Foundation(2022M722688)。
文摘The polysulfides shuttle effect,sluggish sulfur redox kinetics and the corrosion of the Li anode have become important factors limiting the commercial application of lithium-sulfur batteries(LSBs).Herein,the polyoxometalate(POM)nanoclusters with high catalytic activity and cobalt selenide with strong polarity are initially complemented to construct a PMo_(12)/CoSe_(2)@NC/CNTs multifunctional separator that can simultaneously solve the above problems.A series of experimental and theoretical results demonstrate that the Keggin-type POM,H_(3)PMo_(12)O_(40)nH_(2)O(PMo_(12))nanoclusters could function as catalytic centers for sulfur-involved transformations,with the CoSe_(2)nanoparticles serving as adsorption sites for soluble polysulfides.Accordingly,the assembled battery with the PMo_(12)/CoSe_(2)@NC/CNTs modified separator achieves an initial discharge capacity of 1263.79 mA h g^(-1),maintaining 635.77 mA h g^(-1),with a capacity decay rate of 0.06%per cycle after 500 cycles at 3C.This work provides a strategic approach for incorporating POM nanoclusters with polar periodic nanomaterials in LSB separators,contributing to the development of multifunctional separator materials,thus promoting the advancement of energy storage systems.
基金supported by the National Key R&D Program of China[Grant No.2022YFC2402400]the National Natural Science Foundation of China[Grant No.62275062]+2 种基金Project of Shandong Innovation and Startup Community of High-end Medical Apparatus and Instruments[Grant Nos.2023-SGTTXM-002 and 2024-SGTTXM-005]the Shandong Province Technology Innovation Guidance Plan(Central Leading Local Science and Technology Development Fund)[Grant No.YDZX2023115]the Taishan Scholar Special Funding Project of Shandong Province,and the Shandong Laboratory of Advanced Biomaterials and Medical Devices in Weihai[Grant No.ZL202402].
文摘Optical-resolution photoacoustic microscopy is a novel imaging technique that combines the advantages of optical and ultrasound imaging,enabling high-resolution visualization of biological tissues at the micrometer scale.However,the divergence of the excited Gaussian beam limits the depth-of-field of the system to less than 100μm,which hinders accurate three-dimensional imaging of living tissues and restrictsits applicability in biological research.Therefore,there is an urgent need for an effective method to enhance the depth-of-field without altering the hardware configuration.This paper presents a photoacoustic microscopy depth-of-field extension method and system based on three-dimensional continuity and sparsity deconvolution.This method utilizes a depth-varying point spread function and incorporates continuity and sparsity con-straints into the deconvolution process to mitigate the effect of background noise,enhancing the stability and accuracy of the depth-of-field extension.Experimental results using tungsten wire phantoms suggest that the depth-of-field of system can be extended to 650 pm,which is 7.2 times greater than conventional system,while improving the resolution of the defocused region by an average factor of 3.5.Furthermore,experiments on zebrafish and nude mouse ears with irregular topologies demonstrate that the proposed method successfully overcomes image blurring and the loss of structural information due to limited depth-of-field.All the results suggest that the system with higher lateral resolution and enhanced depth-of-field has significant potential for a wide range of practical biomedical applications.
基金supported by the National Natural Science Foundation of China(No.51571204)the support of the Youth Scientific and Innovation Research Team for Advanced Surface Functional Materials(Southwest Petroleum University,No.2018CXTD06)the Young Scholars Development Found of Southwest Petroleum University(No.201899010040).
文摘Stress corrosion cracking(SCC) of an SA508-309 L/308 L–316 L dissimilar metal weld joint in primary pressurized water reactor environment was investigated by the interrupted slow strain rate tension tests following a microstructure characterization. The 308 L weld metal shows a higher content of δ ferrite than the 309 L weld metal. In addition, no obvious Cr-depletion but carbides precipitation at δ phase boundaries was observed in both 308 L and 309 L weld metals. The slow strain rate tension tests showed that the SCC susceptibility of the base and weld metals of the dissimilar metal weld joint follows the order of SA508 < 308 L weld metal < the heat affected zone of 316 L base metal < 309 L weld metal.The higher SCC susceptibility of 309 L weld metal than that of 308 L weld metal is likely due to the lower content of δ ferrite. In addition, a preferential SCC initiation in the 309 L weld metal adjacent to 308 L weld metal is attributed to few carbides in this region.
基金Project supported by the National Natural Science Foundation oX f China(Nos.81371302,81571127,and 31872796)the National Basic Research Program(973)of China(No.2014CB910300)+1 种基金the National Major New Drugs Innovation and Development(No.2018ZX X09711001-004-005)the Zhejiang Provincial Natural Science Foundation of China(Nos.LR16H090001 and LY19B020013)
文摘As a crucial signaling molecule, calcium plays a critical role in many physiological and pathological processes by regulating ion channel activity. Recently, one study resolved the structure of the transient receptor potential melastatin 2(TRPM2) channel from Nematostella vectensis(nvTRPM2). This identified a calcium-binding site in the S2–S3 loop, while its effect on channel gating remains unclear. Here, we investigated the role of this calcium-binding site in both nvTRPM2 and human TRPM2(hTRPM2) by mutagenesis and patch-clamp recording. Unlike hTRPM2, nvT RPM2 cannot be activated by calcium alone. Moreover, the inactivation rate of nvTRPM2 was decreased as intracellular calcium concentration was increased. In addition, our results showed that the four key residues in the calcium-binding site of S2–S3 loop have similar effects on the gating processes of nvTRPM2 and hTRPM2. Among them, the mutations at negatively charged residues(glutamate and aspartate) substantially decreased the currents of nvT RPM2 and hTRPM2. This suggests that these sites are essential for calcium-dependent channel gating. For the charge-neutralizing residues(glutamine and asparagine) in the calcium-binding site, our data showed that glutamine mutating to alanine or glutamate did not affect the channel activity, but glutamine mutating to lysine caused loss of function. Asparagine mutating to aspartate still remained functional, while asparagine mutating to alanine or lysine led to little channel activity. These results suggest that the side chain of glutamine has a less contribution to channel gating than does asparagine. However, our data indicated that both glutamine mutating to alanine or glutamate and asparagine mutating to aspartate accelerated the channel inactivation rate, suggesting that the calcium-binding site in the S2–S3 loop is important for calcium-dependent channel inactivation. Taken together, our results uncovered the effect of four key residues in the S2–S3 loop of TRPM2 on the TRPM2 gating process.
基金This work was supported by the National Key R&D Research Program of China(Nos.2018YFA0209600,2017YFA0208300)the National Natural Science Foundation of China(Nos.51925207,U1910210,51872277,52002083,22005292,51802302)+4 种基金the DNL cooperation Fund,CAS(DNL180310)the Fundamental Research Funds for the Central Universities(WK2060140026,WK3430000006,WK2060000009)the National Synchrotron Radiation Laboratoi-y(KY2060000173)the National Postdoctoral Program for Innovative Talents(BX20200318)the China Postdoctoral Science Foundation(Nos.2020M672533,2019TQ0296,2020M682012).
文摘Potassium-selenium(K-Se)batteries have attracted more and more attention because of their high theoretical specific capacity and natural abundance of K resources.However,dissolution of polyselenides,large volume expansion during cycling and low utilization of Se remain great challenges,leading to poor rate capability and cycle life.Herein,N/O dual-doped carbon nanofibers with interconnected micro/mesopores(MMCFs)are designed as hosts to manipulate Se molecular configuration for advanced flexible K-Se batteries.The micropores play a role in confining small Se molecule(Se_(2–3)),which could inhibit the formation of polyselenides and work as physical barrier to stabilize the cycle performance.While the mesopores can confine long-chain Se(Se_(4–7)),promising sufficient Se loading and contributing to higher discharge voltage of the whole Se@MMCFs composite.The N/O co-doping and the 3D interpenetrating nanostructure improve electrical conductivity and keep the structure integrity after cycling.The obtained Se_(2–3)/Se_(4–7)@MMCFs electrode exhibits an unprecedented cycle life(395 mA h g^(−1) at 1 A g^(−1) after 2000 cycles)and high specific energy density(400 Wh kg^(−1),nearly twice the specific energy density of the Se_(2–3)@MMCFs).This study offers a rational design for the realization of a high energy density and long cycle life chalcogen cathode for energy storage.
基金Project supported by the National Key Research and Development Program of China(Grant No.2017YFA0701005)the National Natural Science Foundation of China(Grant Nos.61427814 and 51807161)the Natural Science Foundation of Shaanxi Province,China(Grant No.2019JZ-04).
文摘We present a high-performance terahertz(THz)radiation source based on the photon-activated charge domain(PACD)quenched mode of GaAs photoconductive antennas(GaAs PCA).The THz radiation characteristics of the GaAs PCA under different operating modes are studied.Compared with the linear mode,the intensity of THz wave radiated by the GaAs PCA can be greatly enhanced due to the avalanche multiplication effect of carriers in the PACD quenched mode.The results show that when the carrier multiplication ratio is 16.92,the peak-to-peak value of THz field radiated in the PACD quenched mode increases by as much as about 4.19 times compared to the maximum values in the linear mode.
基金the financial support from the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0450201)the National Key R&D Program of China(2018YFA0209600)+2 种基金USTC Research Funds of the Double FirstClass Initiative(YD2060002033)the Fundamental Research Funds for the Central Universities(WK2060000060)the National Synchrotron Radiation Laboratory(KY2060000199)。
文摘Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commercialization almost all exhibit low Na-ion conductivities of around 10^(-5)S cm^(-1)or lower.Here,we report a chloride solid electrolyte,Na_(2.7)ZFCl_(5.3)O_(0.7),which reaches a Na-ion conductivity of 2.29×10^(-4)S cm^(-1)at 25℃without involving overly expensive raw materials such as rare-earth chlorides or Na_(2)S.In addition to the efficient ion transport,Na_(2.7)ZrCl_(5.3)O_(0.7)also shows an excellent deformability surpassing that of the widely studied Na_(3)PS_(4),Na_(3)SbS_(4),and Na_(2)ZrCl_(6)solid electrolytes.The combination of these advantages allows the all-solid-state cell based on Na_(2.7)ZrCl_(5.3)O_(0.7)and NaCrO_(2)to realize stable room-temperature cycling at a much higher specific current than those based on other non-viscoelastic chloride solid electrolytes in literature(120 mA g^(-1)vs.12-55 mA g^(-1));after 100 cycles at such a high rate,the Na_(2.7)ZFCl_(5.3)O_(0.7)-based cell can still deliver a discharge capacity of 80 mAh g^(-1)at25℃.
基金supported by the National Key Basic Research Program of China(Grant No.2019YFA0308500,2020YFA0309100,and 2021YFA1400701)the National Natural Science Foundation of China(Grant No.12174437,No.12222414,No.12074416,and No.12104054)+4 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB33030200)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.Y2022003)the China Postdoctoral Innovative Talent Support Program(Grant No.BX20240409)the China Postdoctoral Science Foundation(Grant No.2024M763507)the Beijing Natural Science Foundation(Grant No.1222035).
文摘Antiferromagnetism has become a promising candidate for the next generation electronic devices due to its thermal stability,low energy consumption,and fast switching speed.However,the canceling of the net magnetic moment in antiferromagnetic order presents great challenge on quantitative characterization and modulation,hindering its investigation and application.In this work,utilizing the optical second harmonic generation(SHG)in a wide temperature range,the integrated differential phase contrast scanning transmission electron microscopy,and firstprinciples calculations,we performed a quantitative study on the evolution of non-collinear antiferromagnetic order in BiFeO_(3)films with a series of strains.We found that the antiferromagnetic coupling was significantly enhanced,featured by the increase of Néel temperature from 428 K to 646 K,and by one order of enhancement of SHG intensity contributed from the G-type antiferromagnetic order by strain manipulation from-2.4%to+0.6%.We attributed the enhancement of the antiferromagnetic coupling to the enhancement of the superexchange interaction as the Fe-O-Fe bond angle approaches 180°when the in-plane lattice constants increase,which might also result in a tendency from a non-collinear antiferromagnetic order to a collinear one.Our work not only bridges the antiferromagnetic order and the strain manipulation in epitaxial multiferroics,more importantly,also paves a way for quantitative characterization by SHG technology and the precise manipulation of antiferromagnetism.
基金supported by the National Natural Science Foundation of China(Nos.U21A2060,22178116,and 21978097)Natural Science Foundation of Shanghai(No.22ZR1417400)+3 种基金the Fundamental Research Funds for the Central Universities(No.JKD01231701)China Postdoctoral Science Foundation(No.2023M731084)Shanghai Sailing Program of China(No.23YF1408900)Fundamental Research Funds for the Central Universities(Nos.222201817001,50321041918013,and JKA01221601).
文摘The commercialization of lithium-sulfur(Li-S)batteries has been struggling due to the uncontrollable shuttle effect and slow polysulfides redox kinetics.Single atom alloys(SAAs)with the advantages of single-atom and nanoparticle catalysts are still rarely studied in the field of Li-S batteries.Herein,a NiCo_(SAA)was supported on MXene(NiCo_(SAA)-MXene),which served as the cascade electrocatalyst for improving the Li^(+)desolvation and polysulfides conversion kinetics.In this design,the special structure of the single atom alloy can fully inhibit the mutual stacking of MXene and achieve good stability,while the MXene nanosheet serves as support to enable the uniform dispersion of single atom alloy with ultra-small particle size,facilitating maximum atom utilization.Moreover,the electron cloud of Co was redistributed with the assistance of Ni,resulting in an enhanced electrocatalytic performance,as confirmed by theoretical calculations.At the cascade catalysis of NiCo_(SAA)-MXene,more free Li^(+)was released,and the diffusion of Li^(+)was enhanced to participate in the polysulfides redox reaction,effectively inhibiting the shuttle effect of polysulfides,as proved by in-situ/ex-situ Raman and electrochemical characterization.As a result,the Li-S battery with NiCo_(SAA)-MXene modified separator achieved a reversible capacity of 992 mAh·g^(-1)at 0.2 C after 100 cycles and a superior rate capability of 746 mAh·g^(-1)at 4 C.At a high sulfur loading of 4.7 mg·cm^(-2),the Li-S battery also maintains an excellent cycling stability(100 cycles,3.1 mAh·cm^(-2)),demonstrating significant promise for commercial applications.
基金financially supported by the National Natural Science Foundation of China(Grant No.51571204)
文摘Microstructure of the heat affected zone （HAZ） of a 308L-316L stainless steel （SS） weld joint and its corrosion behavior in high temperature water were studied. Peak of the residual strain was observed to approach to the fusion boundary in the HAZ while the strain increased from the top to root areas of the HAZ. The root area of the HAZ shows a lower corrosion resistance in high temperature water than the top and middle areas of the HAZ. This is attributed to a higher level of residual strain in association with a higher density of tangled dislocations in the top area of the HAZ. The results suggest that the residual strain in the HAZ could also promote the SCC through its effect on corrosion, in addition to that on the local microstructure and mechanical property of the steel.
