Accurate prediction of coal and gas outburst(CGO)hazards is paramount in gas disaster prevention and control.This paper endeavors to overcome the constraints posed by traditional prediction indexes when dealing with C...Accurate prediction of coal and gas outburst(CGO)hazards is paramount in gas disaster prevention and control.This paper endeavors to overcome the constraints posed by traditional prediction indexes when dealing with CGO incidents under low gas pressure conditions.In pursuit of this objective,we have studied and established a mechanical model of the working face under abnormal stress and the excitation energy conditions of CGO,and proposed a method for predicting the risk of CGO under abnormal stress.On site application verification shows that when a strong outburst hazard level prediction is issued,there is a high possibility of outburst disasters occurring.In one of the three locations where we predicted strong outburst hazards,a small outburst occurred,and the accuracy of the prediction was higher than the traditional drilling cuttings index S and drilling cuttings gas desorption index q.Finally,we discuss the mechanism of CGO under the action of stress anomalies.Based on the analysis of stress distribution changes and energy accumulation characteristics of coal under abnormal stress,this article believes that the increase in outburst risk caused by high stress abnormal gradient is mainly due to two reasons:(1)The high stress abnormal gradient leads to an increase in the plastic zone of the coal seam.After the working face advances,it indirectly leads to an increase in the gas expansion energy that can be released from the coal seam before reaching a new stress equilibrium.(2)Abnormal stress leads to increased peak stress of coal body in front of working face.When coal body in elastic area transforms to plastic area,its failure speed is accelerated,which induces accelerated gas desorption and aggravates the risk of outburst.展开更多
Ethylene glycol oxidation reaction(EGOR)is important to address the environmental issues caused by the increased production of polyethylene terephthalate(PET).Metal organic frameworks(MOFs)with superior stability,high...Ethylene glycol oxidation reaction(EGOR)is important to address the environmental issues caused by the increased production of polyethylene terephthalate(PET).Metal organic frameworks(MOFs)with superior stability,high specific surface area and excellent catalytic performance can convert PET into valuable products through EGOR and hydrogen evolution reaction(HER).Herein,a microbial template strategy was adopted to prepare carbon sphere-supported orthogonal nanosheet bimetallic MOF catalysts.The prepared catalyst needs only 1.42 V,307 mV,and 1.83 V at a current density of 100 mA cm^(-2) for EGOR,HER,and EGOR//HER,respectively.More importantly,it can stably perform for at least 160 h at a current density of 500 mA cm^(-2).The high specific surface area of bimetallic MOF and the synergistic effect of yeast carbon shell increase the contact area between the intrinsic active sites and*OH and EG,thus improving the EGOR and HER catalytic activity and stability.This work provides a novel strategy to construct bimetallic orthogonal electrocatalysts with efficient HER//EGOR performance,which is of great significance for achieving sustainable energy conversion and environmental purification.展开更多
Superhydrophobic surfaces(SHS)and slippery lubricant-infused porous surfaces(SLIPS)attract great attention due to their multiple properties in both industries and our daily lives.Here,we first fabricated the SHS with ...Superhydrophobic surfaces(SHS)and slippery lubricant-infused porous surfaces(SLIPS)attract great attention due to their multiple properties in both industries and our daily lives.Here,we first fabricated the SHS with micro-scale flower-like structures composed of nano-sheets on pipeline steel substrate.Then,we obtained the SLIPS by spin-coating lubricant into gaps of micro-scale flower-like structures,with the air still trapped among gaps of nano-sheets.The SLIPS shows excellent liquid repellency as the SHS.The SLIPS also shows stability after the scour of flowing water.These results of polarization curves(Tafel)and electrochemical impedance spectroscopies deduced the SLIPS with better and more stable anti-corrosion property than the SHS.Compared with the SHS,the lack of attachment and CaCO_(3) on the SLIPS indicates that the SLIPS demonstrates better anti-fouling and anti-scaling properties than the SHS.Moreover,the SLIPS shows promising wear resistance under the abrasion simulated by sandpaper compared with the SHS.Notably,the air trapped among nano-sheets is conducive to the lubricant flowing to the surface quickly,exhibiting spontaneous self-healing in atmosphere,even if part flower-like structures of the SLIPS subject to damage with the lubricant consumed after scratched.展开更多
A supercontinuum white laser with ultrabroad bandwidth,intense pulse energy,and high spectral flatness can be accomplished via synergic action of third-order nonlinearity(3rd-NL)and second-order nonlinearity.In this w...A supercontinuum white laser with ultrabroad bandwidth,intense pulse energy,and high spectral flatness can be accomplished via synergic action of third-order nonlinearity(3rd-NL)and second-order nonlinearity.In this work,we employ an intense Ti:sapphire femtosecond laser with a pulse duration of 50 fs and pulse energy up to 4 mJ to ignite the supercontinuum white laser.Remarkably,we use water instead of the usual solid materials as the 3rd-NL medium exhibiting both strong self-phase modulation and stimulated Raman scattering effect to create a supercontinuum laser with significantly broadened bandwidth and avoid laser damage and destruction.Then the supercontinuum laser is injected into a water-embedded chirped periodically poled lithium niobate crystal that enables broadband and high-efficiency second-harmonic generation.The output white laser has a 10 dB bandwidth encompassing 413 to 907 nm,more than one octave,and a pulse energy of 0.6 mJ.This methodology would open up an efficient route to creating a long-lived,high-stability,and inexpensive white laser with intense pulse energy,high spectral flatness,and ultrabroad bandwidth for application to various areas of basic science and high technology.展开更多
Organic electrochemical transistors(OECTs)represent a promising platform for neuromorphic computing,owing to their unique ability to achieve non-volatile memory under low-voltage operation.The achievement of biologica...Organic electrochemical transistors(OECTs)represent a promising platform for neuromorphic computing,owing to their unique ability to achieve non-volatile memory under low-voltage operation.The achievement of biologically relevant synaptic functionalities within OECTs remains challenging due to uncontrolled ionic-electronic coupling,limited device stability,and fabrication complexity.Herein,we report synaptic OECTs based on polymer blends of the ion-permeable semiconductor(Pg2TT)and the ion-blocking polymers(PMMA,PS),which are designed to modulate ionic diffusion within the transistor channel.Morphological and electrochemical characterizations demonstrate that the incorporation of these blocking polymers induces nanofibrous phase separation,resulting in continuous Pg2T-T nanofibers that facilitate electronic transport,interspersed with PMMA-rich domains serving as physical barriers to ion migration.Based on the systematic evaluation of OECT transistor and synapse performances,we identified an optimal Pg2T-T to PMMA composition ratio of 1:2,which yields significantly enhanced synaptic behaviors,including excitatory postsynaptic current(EPSC),tunable paired-pulse facilitation and depression(PPF/PPD),as well as stable long-term potentiation and depression(LTP/LTD)across multiple writing/erasing cycles.Moreover,by integrating the device into a neuromorphic system based on the Fashion-MNIST dataset,achieving a classification accuracy of 80.41%,which surpassed the ideal synapse baseline,attributed to the beneficial stochasticity of physical weight updates.These results highlight a scalable material strategy for high-robust synaptic emulation in OECTs,offering a promising foundation for future bioinspired neuromorphic hardware.展开更多
Copper,a critical strategic metal primarily from chalcopyrite,is widely used.However,a large amount of chalcopyrite is not effectively recovered resulting from its surface characteristics due to its fine size.This stu...Copper,a critical strategic metal primarily from chalcopyrite,is widely used.However,a large amount of chalcopyrite is not effectively recovered resulting from its surface characteristics due to its fine size.This study introduced the use of surface roughness(SR)as a core indicator to evaluate chalcopyrite's flotation performance.Two modification methods including mechanical activation(grinding)and nanoparticle collectors(NPCs)modification were systematically investigated.Grinding enhanced SR from 1.274 to 3.593,improved yield from 55.14%to 63.21%,and increased hydrophobicity,as demonstrated by the rise in contact angle from 55.74°to 68.38°.NPCs demonstrated superior performance,with SR reaching 4.987,contact angle up to 90.75°,and yield as high as 91.45%.The results demonstrated that physical modification(grinding)improved flotability through roughness enhancement,while NPCs offered an optimal solution for chalcopyrite flotation by combining the advantages of increased SR with strong collector interaction.Molecular dynamics simulations revealed the following diffusion coefficient order:CTAB(cetyltrimethylammonium bromide)-NPC>SDS(sodium dodecyl sulfate)-NPC>PEG(polyethylene glycol)-NPC>BX(butyl xanthate)>no collector.This trend demonstrated that higher water molecule mobility corresponded to reduced surface-water binding and enhanced chalcopyrite hydrophobicity induced by collector adsorption.These findings provide valuable insights for optimizing copper mineral processing,particularly for fine chalcopyrite resources.展开更多
Large-scale ultraviolet photodetectors are highly promising for detection of weak signals and have the potential for widespread applications in high-tech areas such as aerospace detection and wearable devices.However,...Large-scale ultraviolet photodetectors are highly promising for detection of weak signals and have the potential for widespread applications in high-tech areas such as aerospace detection and wearable devices.However,the commonly used window electrodes lack transparency to ultraviolet light.Although ultraviolet photodetectors based on Ag nanowires exhibit good response due to their broad transparency range,the sharp interface between the Ag nanowires and the semiconductor renders them extremely unstable.Surface protection is considered to enhance the stability and lifespan of these devices.Our research has revealed that amorphous Ga_(2)O_(3) can fully encapsulate the surface of Ag nanowires and securely affix it to the Nio film,resulting in a stable performance with a high responsivity of 48 mA W-1 and detectivity of 6.1×10^(11) Jones for 254 nm light.The unpacked device exhibited a stable photocurrent,showing only 6.8%degradation after 3 months in ambient air.Finally,a large-scale(5 cm×4 cm,with 12 cm^(2) of active area)ultraviolet photodetector with a Ga_(2)O_(3)-protected Ag nanowire electrode was prepared,which demonstrated a milliamp-level photocurrent under weak ultraviolet illumination that can be directly read by a conventional multimeter in practical scenarios,indicating the promising prospects of this device for future commercial applications.展开更多
This work investigates spatial evolution characteristics during second-harmonic generation(SHG)through numerical and experimental study by employing a dual-pass Nd:YLF amplifier chain.Through simultaneous monitoring o...This work investigates spatial evolution characteristics during second-harmonic generation(SHG)through numerical and experimental study by employing a dual-pass Nd:YLF amplifier chain.Through simultaneous monitoring of conversion efficiency dynamics and beam profile evolution,we demonstrate that the spatial uniformity follows deterministic transformation patterns during nonlinear frequency conversion.Notably,optimization of beam uniformity was achieved at the fundamental power density of 0.478 GW/cm2in our configuration,while maintaining conversion efficiency exceeding 85%.展开更多
This paper provides an overview of the current status of ultrafast and ultra-intense lasers with peak powers exceeding100 TW and examines the research activities in high-energy-density physics within China.Currently,1...This paper provides an overview of the current status of ultrafast and ultra-intense lasers with peak powers exceeding100 TW and examines the research activities in high-energy-density physics within China.Currently,10 high-intensity lasers with powers over 100 TW are operational,and about 10 additional lasers are being constructed at various institutes and universities.These facilities operate either independently or are combined with one another,thereby offering substantial support for both Chinese and international research and development efforts in high-energy-density physics.展开更多
A high-energy and high-efficiency 2μm nanosecond optical parametric oscillator(OPO)with excellent energy stability is reported.The cavity adopts a plane–plane configuration with two potassium titanyl phosphate(KTP)c...A high-energy and high-efficiency 2μm nanosecond optical parametric oscillator(OPO)with excellent energy stability is reported.The cavity adopts a plane–plane configuration with two potassium titanyl phosphate(KTP)crystals inserted using a spatial walk-off compensated orientation.The KTP-OPO is pumped by a 1064 nm Nd:YAG Q-switched laser at a repetition rate of 10 Hz and produces a maximum pulse energy of 162.6 m J at a pump energy of 431 m J,corresponding to an optical conversion efficiency of 37.7%and a slope efficiency of 45.2%.The energy stability shows a record root mean square(RMS)of0.4%over 30 min.To our knowledge,this represents the highest 2μm pulse energy achieved via the 1μm laser-pumped KTPOPO scheme,which could be an excellent laser source for driving extreme ultraviolet(EUV)radiations in the subsequent demonstration experiments.展开更多
Neuromorphic computing targets realizing biomimetic or intelligence systems capable of processing abundant tasks in parallel analogously to our brain,and organic electrochemical transistors(OECTs)that rely on the mixe...Neuromorphic computing targets realizing biomimetic or intelligence systems capable of processing abundant tasks in parallel analogously to our brain,and organic electrochemical transistors(OECTs)that rely on the mixed ionic-electronic synergistic couple possess significant similarity to biological systems for implementing synaptic functions.However,the lack of reliable stretchability for synaptic OECTs,where mechanical deformation occurs,leads to consequent degradation of electrical performance.Herein,we demonstrate stretchable synaptic OECTs by adopting a three-dimensional poly(3-hexylthiophene)(P3HT)/styrene-ethylene-butylene-styrene(SEBS)blend porous elastic film for neuromorphic computing.Such architecture shows the full capability to emulate biological synaptic behaviors.Adjusting the accumulated layer numbers of porous film enables tunable OECT output and hysteresis,resulting in transition in plasticity.Especially,with a trilayer porous film,large-scale conductance and hysteresis are endorsed for efficient mimicking of memory-dependent synapse behavior.Benefitted from the interconnected three-dimensional porous structures,corresponding stretchable synaptic OECTs exhibit excellent mechanical robustness when stretched at a 30%strain,and maintain reliable electrical characteristics after 500 stretching cycles.Furthermore,near-ideal weight updates with near-zero nonlinearities,symmetricity in long-term potentiation(LTP)and depression,and applications for image simulation are validated.This work paves a universal design strategy toward highperformance stretchable neuromorphic computing architecture and could be extended to other flexible/stretchable electronics.展开更多
A high-brightness ultrabroadband supercontinuum white laser is desirable for various fields of modern science.Here,we present an intense ultraviolet-visible-infrared full-spectrum femtosecond laser source(with 300–50...A high-brightness ultrabroadband supercontinuum white laser is desirable for various fields of modern science.Here,we present an intense ultraviolet-visible-infrared full-spectrum femtosecond laser source(with 300–5000 nm 25 dB bandwidth)with 0.54 mJ per pulse.The laser is obtained by sending a 3.9μm,3.3 mJ mid-infrared pump pulse into a cascaded architecture of gas-filled hollow-core fiber,a bare lithium niobate crystal plate,and a specially designed chirped periodically poled lithium niobate crystal,under the synergic action of second and third order nonlinearities such as high harmonic generation and self-phase modulation.This full-spectrum femtosecond laser source can provide a revolutionary tool for optical spectroscopy and find potential applications in physics,chemistry,biology,material science,industrial processing,and environment monitoring.展开更多
A femtosecond mid-infrared optical vortex laser can be used for high harmonic generation to extend cutoff energy to the kilo-electron-volt range with orbital angular momentum,as well as other secondary radiations.For ...A femtosecond mid-infrared optical vortex laser can be used for high harmonic generation to extend cutoff energy to the kilo-electron-volt range with orbital angular momentum,as well as other secondary radiations.For these,we demonstrate a high-energy femtosecond 4μm optical vortex laser based on optical parametric chirped pulse amplification(OPCPA)for the first time.The optical vortex seed is generated from a femtosecond 4μm laser by a silicon spiral phase plate with the topological charge l of 1 before the stretcher.Through using a two-stage collinear OPCPA amplifier,the chirped vortex pulse is amplified to 12.4 m J with 200 nm full width at half-maximum bandwidth.After compression,the vortex laser pulse with 9.53 m J,119 fs can be obtained.Furthermore,the vortex characteristics of the laser beam are investigated and evaluated.This demonstration can scale to generate a higher-peak-power vortex mid-IR laser and pave a new way for high field physics.展开更多
An effective damage test method based on a marker-based watershed algorithm with gray control(MWGC) is proposed to study the properties of damage induced by near-field laser irradiation for large-aperture laser facili...An effective damage test method based on a marker-based watershed algorithm with gray control(MWGC) is proposed to study the properties of damage induced by near-field laser irradiation for large-aperture laser facilities.Damage tests were performed on fused silica samples and information on the size of damage sites was obtained by this new algorithm,which can effectively suppress the issue of over-segmentation of images resulting from non-uniform illumination in darkfield imaging.Experimental analysis and results show that the lateral damage growth on the exit surface is exponential,and the number of damage sites decreases sharply with damage site size in the damage site distribution statistics.The average damage growth coefficients fitted according to the experimental results for Corning-7980 and Heraeus-Suprasil312 samples at 351 nm are 1.10 ± 0.31 and 0.60 ± 0.09,respectively.展开更多
We present a high-peak-power,near-infrared laser system based on optical parametric chirped pulse amplification pumped by a home-built picosecond pumping laser,which can generate over 40 mJ energy at 1450 nm center wa...We present a high-peak-power,near-infrared laser system based on optical parametric chirped pulse amplification pumped by a home-built picosecond pumping laser,which can generate over 40 mJ energy at 1450 nm center wavelength and operate at 100 Hz repetition rate.Subsequently,the chirped laser pulses are compressed down to 60 fs with 26.5 mJ energy,corresponding to a peak power of 0.44 TW. This high-energy,long-wavelength laser source is highly suitable for driving various nonlinear optical phenomena,such as high-order harmonic generation and high-flux coherent extreme ultraviolet/soft X-ray radiation.展开更多
Infrared femtosecond optical vortices open up many new research fields,such as optical micro–nano manipulation,time-resolved nonlocal spectroscopy in solids,vortex secondary radiation and particle generations.In this...Infrared femtosecond optical vortices open up many new research fields,such as optical micro–nano manipulation,time-resolved nonlocal spectroscopy in solids,vortex secondary radiation and particle generations.In this article,we demonstrate a femtosecond optical vortex laser system based on a two-stage optical parametric amplifier.In our experiment,1.45µm vortex signal pulses with energy of 190µJ and 1.8µm vortex idler pulses with energy of 158µJ have been obtained,and the pulse durations are 51 and 48 fs,respectively.Both the energy fluctuations of the signal and idler pulses are less than 0.5%(root mean square),and the spectral fluctuations are less than 1.5%within 1 hour.This type of highly stable femtosecond optical vortex laser has a wide range of applications for vortex strong-field physics.展开更多
We demonstrate an ultra-broadband high temporal contrast infrared laser source based on cascaded optical parametric amplification,hollow-core fiber(HCF)and second harmonic generation processes.In this setup,the spectr...We demonstrate an ultra-broadband high temporal contrast infrared laser source based on cascaded optical parametric amplification,hollow-core fiber(HCF)and second harmonic generation processes.In this setup,the spectrum of an approximately 1.8μm laser pulse has near 1μm full bandwidth by employing an argon gas-filled HCF.Subsequently,after frequency doubling with cascaded crystals and dispersion compensation by a fused silica wedge pair,9.6 fs(~3cycles)and 150μJ pulses centered at 910 nm with full bandwidth of over 300 nm can be generated.The energy stability of the output laser pulse is excellent with 0.8%(root mean square)over 20 min,and the temporal contrast is>10^(12)at-10 ps before the main pulse.The excellent temporal and spatial characteristics and stability make this laser able to be used as a good seed source for ultra-intense and ultrafast laser systems.展开更多
The generation of high-peak-power,few-cycle mid-infrared(MIR)pulses using coherent beam combination and nonlinear pulse compression techniques simultaneously is demonstrated.The two pulses,with identical pulse energy ...The generation of high-peak-power,few-cycle mid-infrared(MIR)pulses using coherent beam combination and nonlinear pulse compression techniques simultaneously is demonstrated.The two pulses,with identical pulse energy of 2.8 mJ and pulse duration of 160 fs,are coherently combined at the input end of a krypton-filled hollow-core fiber(HCF),and then the bandwidth of the combined pulse is broadened to near an optical octave due to strong phase modulations,and the temporal width is compressed into a few-cycle regime.Finally,a 2.7 mJ,22.9 fs,20 Hz laser at 4μm can be obtained,and the pulse peak power is greatly enhanced compared with that of conventional single-channel optical parametric chirped pulse-amplification systems.Furthermore,the peak power generated from this system has the prospect of further scaling up through use of more channels of coherent combination,which can pave a way to generate higher peak power ultra-intense MIR pulses for strong-field physics.展开更多
Chronic wounds(e.g.diabetic wounds,pressure wounds,vascular ulcers,etc.)do not usually heal in a timely and orderly manner but rather last for years and may lead to irreversible adverse events,resulting in a substanti...Chronic wounds(e.g.diabetic wounds,pressure wounds,vascular ulcers,etc.)do not usually heal in a timely and orderly manner but rather last for years and may lead to irreversible adverse events,resulting in a substantial financial burden for patients and society.Recently,a large amount of evidence has proven that cellular senescence has a crucial influence on chronic nonhealing wounds.As a defensive mechanism,cell senescence is a manner of cell-cycle arrest with increased secretory phenotype to resist death,preventing cells from stress-induced damage in cancer and noncancer diseases.A growing amount of research has advanced the perception of cell senescence in various chronic wounds and focuses on pathological and physiological processes and therapies targeting senescent cells.However,previous reviews have failed to sum up novel understandings of senescence in chronic wounds and emerging strategies targeting senescence.Herein,we discuss the characteristics and mechanisms of cellular senescence and the link between senescence and chronic wounds as well as some novel antisenescence strategies targeting other diseases that may be applied for chronic wounds.展开更多
We demonstrate the simultaneous temporal contrast improvement and pulse compression of a Yb-doped femtosecond laser via nonlinear elliptical polarization rotation in a solid state multi-pass cell.The temporal contrast...We demonstrate the simultaneous temporal contrast improvement and pulse compression of a Yb-doped femtosecond laser via nonlinear elliptical polarization rotation in a solid state multi-pass cell.The temporal contrast is improved to 109,while the pulse is shortened from 181 to 36 fs,corresponding to a compression factor of 5.The output beam features excellent beam quality with M^(2) values of 1.18×1.16.The total efficiency of the contrast enhancement system exceeds 50%.This technique will have wide applications in high temporal contrast ultra-intense femtosecond lasers.展开更多
基金supported by the National Natural Science Foundation of China(52174162)the Fundamental Research Funds for the Central Universities(FRF-TP-20-002A3).
文摘Accurate prediction of coal and gas outburst(CGO)hazards is paramount in gas disaster prevention and control.This paper endeavors to overcome the constraints posed by traditional prediction indexes when dealing with CGO incidents under low gas pressure conditions.In pursuit of this objective,we have studied and established a mechanical model of the working face under abnormal stress and the excitation energy conditions of CGO,and proposed a method for predicting the risk of CGO under abnormal stress.On site application verification shows that when a strong outburst hazard level prediction is issued,there is a high possibility of outburst disasters occurring.In one of the three locations where we predicted strong outburst hazards,a small outburst occurred,and the accuracy of the prediction was higher than the traditional drilling cuttings index S and drilling cuttings gas desorption index q.Finally,we discuss the mechanism of CGO under the action of stress anomalies.Based on the analysis of stress distribution changes and energy accumulation characteristics of coal under abnormal stress,this article believes that the increase in outburst risk caused by high stress abnormal gradient is mainly due to two reasons:(1)The high stress abnormal gradient leads to an increase in the plastic zone of the coal seam.After the working face advances,it indirectly leads to an increase in the gas expansion energy that can be released from the coal seam before reaching a new stress equilibrium.(2)Abnormal stress leads to increased peak stress of coal body in front of working face.When coal body in elastic area transforms to plastic area,its failure speed is accelerated,which induces accelerated gas desorption and aggravates the risk of outburst.
基金the financial support of the Hubei Key Laboratory for Processing and Application of Catalytic Materials(202440704)the National Natural Science Foundation of China(22102125)The financial support of the Open Research Fund(2024JYBKF06)of Key Laboratory of Material Chemistry for Energy Conversion and Storage,Ministry of Education is also acknowledged.
文摘Ethylene glycol oxidation reaction(EGOR)is important to address the environmental issues caused by the increased production of polyethylene terephthalate(PET).Metal organic frameworks(MOFs)with superior stability,high specific surface area and excellent catalytic performance can convert PET into valuable products through EGOR and hydrogen evolution reaction(HER).Herein,a microbial template strategy was adopted to prepare carbon sphere-supported orthogonal nanosheet bimetallic MOF catalysts.The prepared catalyst needs only 1.42 V,307 mV,and 1.83 V at a current density of 100 mA cm^(-2) for EGOR,HER,and EGOR//HER,respectively.More importantly,it can stably perform for at least 160 h at a current density of 500 mA cm^(-2).The high specific surface area of bimetallic MOF and the synergistic effect of yeast carbon shell increase the contact area between the intrinsic active sites and*OH and EG,thus improving the EGOR and HER catalytic activity and stability.This work provides a novel strategy to construct bimetallic orthogonal electrocatalysts with efficient HER//EGOR performance,which is of great significance for achieving sustainable energy conversion and environmental purification.
基金Natural Science Foundation(ZR2019BEM012)National Natural Science Foundation of China(51905315)+1 种基金Fundamental Research Funds for the Central Universities(20CX02316A)Opening Fund of National Engineering Laboratory of Offshore Geophysical and Exploration Equipment.
文摘Superhydrophobic surfaces(SHS)and slippery lubricant-infused porous surfaces(SLIPS)attract great attention due to their multiple properties in both industries and our daily lives.Here,we first fabricated the SHS with micro-scale flower-like structures composed of nano-sheets on pipeline steel substrate.Then,we obtained the SLIPS by spin-coating lubricant into gaps of micro-scale flower-like structures,with the air still trapped among gaps of nano-sheets.The SLIPS shows excellent liquid repellency as the SHS.The SLIPS also shows stability after the scour of flowing water.These results of polarization curves(Tafel)and electrochemical impedance spectroscopies deduced the SLIPS with better and more stable anti-corrosion property than the SHS.Compared with the SHS,the lack of attachment and CaCO_(3) on the SLIPS indicates that the SLIPS demonstrates better anti-fouling and anti-scaling properties than the SHS.Moreover,the SLIPS shows promising wear resistance under the abrasion simulated by sandpaper compared with the SHS.Notably,the air trapped among nano-sheets is conducive to the lubricant flowing to the surface quickly,exhibiting spontaneous self-healing in atmosphere,even if part flower-like structures of the SLIPS subject to damage with the lubricant consumed after scratched.
基金supported by the Science and Technology Project of Guangdong (Grant No.2020B010190001)the National Natural Science Foundation of China (Grant No.11974119)+1 种基金the Guangdong Innovative and Entrepreneurial Research Team Program (Grant No.2016ZT06C594)the National Key R&D Program of China (Grant No.2018YFA 0306200).
文摘A supercontinuum white laser with ultrabroad bandwidth,intense pulse energy,and high spectral flatness can be accomplished via synergic action of third-order nonlinearity(3rd-NL)and second-order nonlinearity.In this work,we employ an intense Ti:sapphire femtosecond laser with a pulse duration of 50 fs and pulse energy up to 4 mJ to ignite the supercontinuum white laser.Remarkably,we use water instead of the usual solid materials as the 3rd-NL medium exhibiting both strong self-phase modulation and stimulated Raman scattering effect to create a supercontinuum laser with significantly broadened bandwidth and avoid laser damage and destruction.Then the supercontinuum laser is injected into a water-embedded chirped periodically poled lithium niobate crystal that enables broadband and high-efficiency second-harmonic generation.The output white laser has a 10 dB bandwidth encompassing 413 to 907 nm,more than one octave,and a pulse energy of 0.6 mJ.This methodology would open up an efficient route to creating a long-lived,high-stability,and inexpensive white laser with intense pulse energy,high spectral flatness,and ultrabroad bandwidth for application to various areas of basic science and high technology.
基金supported by the Regional Joint Fund of the National Natural Science of China(U21A20492)National Natural Science Foundation of China(62273073)+4 种基金the National Key R&D Program of China(2022YFE0134800&2023YFC2411800)the Sichuan Science and Technology Program(No.2024YFHZ0354)the Sichuan Youth Software Innovation Project Funding(No.MZGC20240059)the Sichuan Natural Science Foundation Youth Program(No.2025ZNSFSC1421)sponsored by the Sichuan Province Key Laboratory of Display Science and Technology.
文摘Organic electrochemical transistors(OECTs)represent a promising platform for neuromorphic computing,owing to their unique ability to achieve non-volatile memory under low-voltage operation.The achievement of biologically relevant synaptic functionalities within OECTs remains challenging due to uncontrolled ionic-electronic coupling,limited device stability,and fabrication complexity.Herein,we report synaptic OECTs based on polymer blends of the ion-permeable semiconductor(Pg2TT)and the ion-blocking polymers(PMMA,PS),which are designed to modulate ionic diffusion within the transistor channel.Morphological and electrochemical characterizations demonstrate that the incorporation of these blocking polymers induces nanofibrous phase separation,resulting in continuous Pg2T-T nanofibers that facilitate electronic transport,interspersed with PMMA-rich domains serving as physical barriers to ion migration.Based on the systematic evaluation of OECT transistor and synapse performances,we identified an optimal Pg2T-T to PMMA composition ratio of 1:2,which yields significantly enhanced synaptic behaviors,including excitatory postsynaptic current(EPSC),tunable paired-pulse facilitation and depression(PPF/PPD),as well as stable long-term potentiation and depression(LTP/LTD)across multiple writing/erasing cycles.Moreover,by integrating the device into a neuromorphic system based on the Fashion-MNIST dataset,achieving a classification accuracy of 80.41%,which surpassed the ideal synapse baseline,attributed to the beneficial stochasticity of physical weight updates.These results highlight a scalable material strategy for high-robust synaptic emulation in OECTs,offering a promising foundation for future bioinspired neuromorphic hardware.
基金funded by the National Natural Science Foundation of China(grant Nos.22478231 and U21A20321)Fundamental Research Program of Shanxi Province(grant No.202403021221011)。
文摘Copper,a critical strategic metal primarily from chalcopyrite,is widely used.However,a large amount of chalcopyrite is not effectively recovered resulting from its surface characteristics due to its fine size.This study introduced the use of surface roughness(SR)as a core indicator to evaluate chalcopyrite's flotation performance.Two modification methods including mechanical activation(grinding)and nanoparticle collectors(NPCs)modification were systematically investigated.Grinding enhanced SR from 1.274 to 3.593,improved yield from 55.14%to 63.21%,and increased hydrophobicity,as demonstrated by the rise in contact angle from 55.74°to 68.38°.NPCs demonstrated superior performance,with SR reaching 4.987,contact angle up to 90.75°,and yield as high as 91.45%.The results demonstrated that physical modification(grinding)improved flotability through roughness enhancement,while NPCs offered an optimal solution for chalcopyrite flotation by combining the advantages of increased SR with strong collector interaction.Molecular dynamics simulations revealed the following diffusion coefficient order:CTAB(cetyltrimethylammonium bromide)-NPC>SDS(sodium dodecyl sulfate)-NPC>PEG(polyethylene glycol)-NPC>BX(butyl xanthate)>no collector.This trend demonstrated that higher water molecule mobility corresponded to reduced surface-water binding and enhanced chalcopyrite hydrophobicity induced by collector adsorption.These findings provide valuable insights for optimizing copper mineral processing,particularly for fine chalcopyrite resources.
基金supported by the National Key R&D Program of China(2022YFB3603202)National Science Foundation of China(62171069)+3 种基金Cooperation projects between universities in Chongqing and institutes affiliated with the Chinese Academy of Sciences(Hz2021019)Natural Science Foundation of Chongqing(CSTB2023NSCQ-LZX0058,CSTB2023TIAD-KPX0022,CSTB2024NSCQ-LZX0009)Scientific and Technological Research Program of Chongqing Municipal Education Commission(KJQN202301315)Key Projects of Anhui Provincial Department of Education(2022AH050116).
文摘Large-scale ultraviolet photodetectors are highly promising for detection of weak signals and have the potential for widespread applications in high-tech areas such as aerospace detection and wearable devices.However,the commonly used window electrodes lack transparency to ultraviolet light.Although ultraviolet photodetectors based on Ag nanowires exhibit good response due to their broad transparency range,the sharp interface between the Ag nanowires and the semiconductor renders them extremely unstable.Surface protection is considered to enhance the stability and lifespan of these devices.Our research has revealed that amorphous Ga_(2)O_(3) can fully encapsulate the surface of Ag nanowires and securely affix it to the Nio film,resulting in a stable performance with a high responsivity of 48 mA W-1 and detectivity of 6.1×10^(11) Jones for 254 nm light.The unpacked device exhibited a stable photocurrent,showing only 6.8%degradation after 3 months in ambient air.Finally,a large-scale(5 cm×4 cm,with 12 cm^(2) of active area)ultraviolet photodetector with a Ga_(2)O_(3)-protected Ag nanowire electrode was prepared,which demonstrated a milliamp-level photocurrent under weak ultraviolet illumination that can be directly read by a conventional multimeter in practical scenarios,indicating the promising prospects of this device for future commercial applications.
基金supported by the National Key R&D Program of China(Nos.2024YFB3613605,2022YFA160440,and 2019YFF01014401)the National Natural Science Foundation of China(Nos.61925507,12388102,62075227,and U21A20138)+3 种基金the National Major Scientific Research Instrument Development Project(No.22227901)the XDB(No.0890101)the Shanghai Rising-Star Program(No.21QA1410200)the Shanghai Science and Technology Committee Program(Nos.22DZ1100300,22560780100,and 23560750200)。
文摘This work investigates spatial evolution characteristics during second-harmonic generation(SHG)through numerical and experimental study by employing a dual-pass Nd:YLF amplifier chain.Through simultaneous monitoring of conversion efficiency dynamics and beam profile evolution,we demonstrate that the spatial uniformity follows deterministic transformation patterns during nonlinear frequency conversion.Notably,optimization of beam uniformity was achieved at the fundamental power density of 0.478 GW/cm2in our configuration,while maintaining conversion efficiency exceeding 85%.
文摘This paper provides an overview of the current status of ultrafast and ultra-intense lasers with peak powers exceeding100 TW and examines the research activities in high-energy-density physics within China.Currently,10 high-intensity lasers with powers over 100 TW are operational,and about 10 additional lasers are being constructed at various institutes and universities.These facilities operate either independently or are combined with one another,thereby offering substantial support for both Chinese and international research and development efforts in high-energy-density physics.
基金supported by the National Key R&D Program of China(No.2022YFA1604401)the National Natural Science Foundation of China(Nos.12388102,62205351,61925507,62075227,and 22227901)+2 种基金the Shanghai Science and Technology Committee Program(Nos.22DZ1100300,22560780100,and 23560750200)the Shanghai Rising-Star Program(No.21QA1410200)the Youth Innovation Promotion Association CAS(No.2020248).
文摘A high-energy and high-efficiency 2μm nanosecond optical parametric oscillator(OPO)with excellent energy stability is reported.The cavity adopts a plane–plane configuration with two potassium titanyl phosphate(KTP)crystals inserted using a spatial walk-off compensated orientation.The KTP-OPO is pumped by a 1064 nm Nd:YAG Q-switched laser at a repetition rate of 10 Hz and produces a maximum pulse energy of 162.6 m J at a pump energy of 431 m J,corresponding to an optical conversion efficiency of 37.7%and a slope efficiency of 45.2%.The energy stability shows a record root mean square(RMS)of0.4%over 30 min.To our knowledge,this represents the highest 2μm pulse energy achieved via the 1μm laser-pumped KTPOPO scheme,which could be an excellent laser source for driving extreme ultraviolet(EUV)radiations in the subsequent demonstration experiments.
基金This work was financially supported by the National Key Research&Development Program of China(No.2022YFE0134800)the National Science Foundation of China(Nos.U21A20492,62275041,and 62273073)+2 种基金the Sichuan Science and Technology Program(Nos.2022YFH0081,2022YFG0012,2022YFG0013,and 2022NSFSC0877)This work was also sponsored by the Sichuan Province Key Laboratory of Display Science and Technology,and Qiantang Science&Technology Innovation CenterW.H.also thanks the financial support of the UESTC Excellent Young Scholar Project。
文摘Neuromorphic computing targets realizing biomimetic or intelligence systems capable of processing abundant tasks in parallel analogously to our brain,and organic electrochemical transistors(OECTs)that rely on the mixed ionic-electronic synergistic couple possess significant similarity to biological systems for implementing synaptic functions.However,the lack of reliable stretchability for synaptic OECTs,where mechanical deformation occurs,leads to consequent degradation of electrical performance.Herein,we demonstrate stretchable synaptic OECTs by adopting a three-dimensional poly(3-hexylthiophene)(P3HT)/styrene-ethylene-butylene-styrene(SEBS)blend porous elastic film for neuromorphic computing.Such architecture shows the full capability to emulate biological synaptic behaviors.Adjusting the accumulated layer numbers of porous film enables tunable OECT output and hysteresis,resulting in transition in plasticity.Especially,with a trilayer porous film,large-scale conductance and hysteresis are endorsed for efficient mimicking of memory-dependent synapse behavior.Benefitted from the interconnected three-dimensional porous structures,corresponding stretchable synaptic OECTs exhibit excellent mechanical robustness when stretched at a 30%strain,and maintain reliable electrical characteristics after 500 stretching cycles.Furthermore,near-ideal weight updates with near-zero nonlinearities,symmetricity in long-term potentiation(LTP)and depression,and applications for image simulation are validated.This work paves a universal design strategy toward highperformance stretchable neuromorphic computing architecture and could be extended to other flexible/stretchable electronics.
基金The authors are grateful for the financial support from the Science and Technology Project of Guangdong(2020B010190001)National Natural Science Foundation of China(11974119,61925507,62075227)+3 种基金Guangdong Innovative and Entrepreneurial Research Team Program(2016ZT06C594)National Key R&D Program of China(2018YFA 0306200)Shanghai Rising-Star Program(21QA1410200)Youth Innovation Promotion Association CAS(2020248).
文摘A high-brightness ultrabroadband supercontinuum white laser is desirable for various fields of modern science.Here,we present an intense ultraviolet-visible-infrared full-spectrum femtosecond laser source(with 300–5000 nm 25 dB bandwidth)with 0.54 mJ per pulse.The laser is obtained by sending a 3.9μm,3.3 mJ mid-infrared pump pulse into a cascaded architecture of gas-filled hollow-core fiber,a bare lithium niobate crystal plate,and a specially designed chirped periodically poled lithium niobate crystal,under the synergic action of second and third order nonlinearities such as high harmonic generation and self-phase modulation.This full-spectrum femtosecond laser source can provide a revolutionary tool for optical spectroscopy and find potential applications in physics,chemistry,biology,material science,industrial processing,and environment monitoring.
基金Strategic Priority Research Program of the Chinese Academy of Sciences(XDB1603)International ST Cooperation Program of China(2016YFE0119300)+2 种基金Program of Shanghai Academic/Technology Research Leader(18XD1404200)Shanghai Municipal Science and Technology Major Project(2017SHZDZX02)National Natural Science Foundation of China(11127901,61925507)。
文摘A femtosecond mid-infrared optical vortex laser can be used for high harmonic generation to extend cutoff energy to the kilo-electron-volt range with orbital angular momentum,as well as other secondary radiations.For these,we demonstrate a high-energy femtosecond 4μm optical vortex laser based on optical parametric chirped pulse amplification(OPCPA)for the first time.The optical vortex seed is generated from a femtosecond 4μm laser by a silicon spiral phase plate with the topological charge l of 1 before the stretcher.Through using a two-stage collinear OPCPA amplifier,the chirped vortex pulse is amplified to 12.4 m J with 200 nm full width at half-maximum bandwidth.After compression,the vortex laser pulse with 9.53 m J,119 fs can be obtained.Furthermore,the vortex characteristics of the laser beam are investigated and evaluated.This demonstration can scale to generate a higher-peak-power vortex mid-IR laser and pave a new way for high field physics.
文摘An effective damage test method based on a marker-based watershed algorithm with gray control(MWGC) is proposed to study the properties of damage induced by near-field laser irradiation for large-aperture laser facilities.Damage tests were performed on fused silica samples and information on the size of damage sites was obtained by this new algorithm,which can effectively suppress the issue of over-segmentation of images resulting from non-uniform illumination in darkfield imaging.Experimental analysis and results show that the lateral damage growth on the exit surface is exponential,and the number of damage sites decreases sharply with damage site size in the damage site distribution statistics.The average damage growth coefficients fitted according to the experimental results for Corning-7980 and Heraeus-Suprasil312 samples at 351 nm are 1.10 ± 0.31 and 0.60 ± 0.09,respectively.
基金funded by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB1603)National Natural Science Foundation of China(Nos.11127901,61521093 and 61635012)+2 种基金International S&T Cooperation Program of China(No.2016YFE0119300)Program of Shanghai Academic/Technology Research Leader(No.18XD1404200)Shanghai Municipal Science and Technology Major Project(No.2017SHZDZX02)
文摘We present a high-peak-power,near-infrared laser system based on optical parametric chirped pulse amplification pumped by a home-built picosecond pumping laser,which can generate over 40 mJ energy at 1450 nm center wavelength and operate at 100 Hz repetition rate.Subsequently,the chirped laser pulses are compressed down to 60 fs with 26.5 mJ energy,corresponding to a peak power of 0.44 TW. This high-energy,long-wavelength laser source is highly suitable for driving various nonlinear optical phenomena,such as high-order harmonic generation and high-flux coherent extreme ultraviolet/soft X-ray radiation.
基金supported by the National Key R&D Program of China(No.2017YFE0123700)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB1603)+5 种基金the National Natural Science Foundation of China(Nos.61925507,62075227,and 12004402)the Program of Shanghai Academic/Technology Research Leader(No.18XD1404200)the Shanghai Municipal Science and Technology Major Project(No.2017SHZDZX02)the Youth Innovation Promotion Association CAS(No.2020248)the Shanghai Sailing Program(No.20YF1455000)the Shanghai Rising-Star Program(No.21QA1410200).
文摘Infrared femtosecond optical vortices open up many new research fields,such as optical micro–nano manipulation,time-resolved nonlocal spectroscopy in solids,vortex secondary radiation and particle generations.In this article,we demonstrate a femtosecond optical vortex laser system based on a two-stage optical parametric amplifier.In our experiment,1.45µm vortex signal pulses with energy of 190µJ and 1.8µm vortex idler pulses with energy of 158µJ have been obtained,and the pulse durations are 51 and 48 fs,respectively.Both the energy fluctuations of the signal and idler pulses are less than 0.5%(root mean square),and the spectral fluctuations are less than 1.5%within 1 hour.This type of highly stable femtosecond optical vortex laser has a wide range of applications for vortex strong-field physics.
基金supported by the National Key R&D Program of China(2017YFE0123700)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB1603)+3 种基金the National Natural Science Foundation of China(61925507,62075227,12004402,61635012)the Program of Shanghai Academic/Technology Research Leader(18XD1404200)the Shanghai Municipal Science and Technology Major Project(2017SHZDZX02)the Youth Innovation Promotion Association CAS(2020248)
文摘We demonstrate an ultra-broadband high temporal contrast infrared laser source based on cascaded optical parametric amplification,hollow-core fiber(HCF)and second harmonic generation processes.In this setup,the spectrum of an approximately 1.8μm laser pulse has near 1μm full bandwidth by employing an argon gas-filled HCF.Subsequently,after frequency doubling with cascaded crystals and dispersion compensation by a fused silica wedge pair,9.6 fs(~3cycles)and 150μJ pulses centered at 910 nm with full bandwidth of over 300 nm can be generated.The energy stability of the output laser pulse is excellent with 0.8%(root mean square)over 20 min,and the temporal contrast is>10^(12)at-10 ps before the main pulse.The excellent temporal and spatial characteristics and stability make this laser able to be used as a good seed source for ultra-intense and ultrafast laser systems.
基金National Key Research and Development Program of China(2017YFE0123700)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB1603)+4 种基金National Natural Science Foundation of China(12004402,61925507,62075227)Program of Shanghai Academic/Technology Research Leader(18XD1404200)Shanghai Municipal Science and Technology Major Project(2017SHZDZX02)Youth Innovation Promotion Association of the Chinese Academy of Sciences(2020248)Shanghai Sailing Program(20YF1455000).
文摘The generation of high-peak-power,few-cycle mid-infrared(MIR)pulses using coherent beam combination and nonlinear pulse compression techniques simultaneously is demonstrated.The two pulses,with identical pulse energy of 2.8 mJ and pulse duration of 160 fs,are coherently combined at the input end of a krypton-filled hollow-core fiber(HCF),and then the bandwidth of the combined pulse is broadened to near an optical octave due to strong phase modulations,and the temporal width is compressed into a few-cycle regime.Finally,a 2.7 mJ,22.9 fs,20 Hz laser at 4μm can be obtained,and the pulse peak power is greatly enhanced compared with that of conventional single-channel optical parametric chirped pulse-amplification systems.Furthermore,the peak power generated from this system has the prospect of further scaling up through use of more channels of coherent combination,which can pave a way to generate higher peak power ultra-intense MIR pulses for strong-field physics.
基金supported by the Science and Technology Innovation Project of Guangdong Province(No.2018KJYZ005)the Natural Science Foundation of Guangdong Province(No.2020A151501107)+1 种基金the Natural Science Foundation of Tibet Autonomous Region(No.XZ2017ZR-ZY021)the Guangdong Province Key FieldR&DProgramme Project(No.2020B1111150001).
文摘Chronic wounds(e.g.diabetic wounds,pressure wounds,vascular ulcers,etc.)do not usually heal in a timely and orderly manner but rather last for years and may lead to irreversible adverse events,resulting in a substantial financial burden for patients and society.Recently,a large amount of evidence has proven that cellular senescence has a crucial influence on chronic nonhealing wounds.As a defensive mechanism,cell senescence is a manner of cell-cycle arrest with increased secretory phenotype to resist death,preventing cells from stress-induced damage in cancer and noncancer diseases.A growing amount of research has advanced the perception of cell senescence in various chronic wounds and focuses on pathological and physiological processes and therapies targeting senescent cells.However,previous reviews have failed to sum up novel understandings of senescence in chronic wounds and emerging strategies targeting senescence.Herein,we discuss the characteristics and mechanisms of cellular senescence and the link between senescence and chronic wounds as well as some novel antisenescence strategies targeting other diseases that may be applied for chronic wounds.
基金supported by the National Key R&D Program of China(No.2017YFE0123700)the National Natural Science Foundation of China(Nos.61925507 and 62075227)+1 种基金the Shanghai Rising-Star Program(No.21QA1410200)the Youth Innovation Promotion Association CAS(No.2020248).
文摘We demonstrate the simultaneous temporal contrast improvement and pulse compression of a Yb-doped femtosecond laser via nonlinear elliptical polarization rotation in a solid state multi-pass cell.The temporal contrast is improved to 109,while the pulse is shortened from 181 to 36 fs,corresponding to a compression factor of 5.The output beam features excellent beam quality with M^(2) values of 1.18×1.16.The total efficiency of the contrast enhancement system exceeds 50%.This technique will have wide applications in high temporal contrast ultra-intense femtosecond lasers.
