Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.Th...Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.The published version showed“Hongzhen Chen”,whereas the correct spelling should be“Hongzheng Chen”.The correct author name has been provided in this Correction,and the original article[1]has been corrected.展开更多
Surface states are expected to play a key role in broadband terahertz(THz) emitters, where photoexcited carrier distributions are confined within about 1 μm of the surface. Optical pump and THz probe spectroscopy was...Surface states are expected to play a key role in broadband terahertz(THz) emitters, where photoexcited carrier distributions are confined within about 1 μm of the surface. Optical pump and THz probe spectroscopy was used to study the dynamics of nonequilibrium charge carriers in both textured and non-textured GaAs substrates.Our findings show that the textured surface acts as an antireflective layer, greatly boosting the infrared pump laser's coupling efficiency into the semi-insulating GaAs substrate. Additionally, texturing introduces a trapassisted recombination pathway, speeding up carrier relaxation and thus reducing Joule heating. Under the same pumping and bias field conditions, the coarse-textured GaAs photoconductive antenna shows nearly 7.85 times stronger THz emission amplitude than the non-textured device, along with improvement in signal-to-noise ratio.At a fixed bias field, higher pump power increases photogenerated carrier density, causing bias field screening and subsequent saturation of THz emission. At fixed pump power, when the bias field reaches ~2.5 kV/cm, both THz emission and photocurrent spectra show a clear kink, signaling intervalley scattering from the Γ valley to the L(X) valleys under high electric fields.展开更多
Dibenzyltoluene(DBT)is a prospective liquid organic hydrogen carrier(LOHC)with low cost and high theoretical hydrogen storage capacity(6.2 wt%).However,the wide application of DBT is severely restricted by expensive n...Dibenzyltoluene(DBT)is a prospective liquid organic hydrogen carrier(LOHC)with low cost and high theoretical hydrogen storage capacity(6.2 wt%).However,the wide application of DBT is severely restricted by expensive noble catalysts.In this work,a new Mg-based metal hydride hydrogenation catalyst,which is composed of MgH_(2),Mg_(2)NiH_(4) and LaH_(3) micro-nano-particles.展开更多
We investigate the carrier, phonon, and spin dynamics in the ferromagnetic semiconductor(In,Fe)Sb using ultrafast optical pump-probe spectroscopy. We discover two anomalies near T^(*)(~40 K) and T^(†)(~200 K) in the p...We investigate the carrier, phonon, and spin dynamics in the ferromagnetic semiconductor(In,Fe)Sb using ultrafast optical pump-probe spectroscopy. We discover two anomalies near T^(*)(~40 K) and T^(†)(~200 K) in the photoexcited carrier dynamics, which can be attributed to the electron-spin and spin-lattice scattering processes influenced by the magnetic phase transition and modifications in magnetic anisotropy. The magnetization change can be revealed by the dynamics of coherent acoustic phonon. We also observe abrupt changes in the photoinduced spin dynamics near T^(*)and T^(†), which not only illustrate the spin-related scatterings closely related to the long-range magnetic order, but also reveal the D'yakonov–Perel and Elliott–Yafet mechanisms dominating at temperatures below and above T^(†), respectively. Our findings provide important insights into the nonequilibrium properties of the photoexcited(In,Fe)Sb.展开更多
Safe and efficient sortie scheduling on the confined flight deck is crucial for maintaining high combat effectiveness of the aircraft carrier.The primary difficulty exactly lies in the spatiotemporal coordination,i.e....Safe and efficient sortie scheduling on the confined flight deck is crucial for maintaining high combat effectiveness of the aircraft carrier.The primary difficulty exactly lies in the spatiotemporal coordination,i.e.,allocation of limited supporting resources and collision-avoidance between heterogeneous dispatch entities.In this paper,the problem is investigated in the perspective of hybrid flow-shop scheduling problem by synthesizing the precedence,space and resource constraints.Specifically,eight processing procedures are abstracted,where tractors,preparing spots,catapults,and launching are virtualized as machines.By analyzing the constraints in sortie scheduling,a mixed-integer planning model is constructed.In particular,the constraint on preparing spot occupancy is improved to further enhance the sortie efficiency.The basic trajectory library for each dispatch entity is generated and a delayed strategy is integrated to address the collision-avoidance issue.To efficiently solve the formulated HFSP,which is essentially a combinatorial problem with tightly coupled constraints,a chaos-initialized genetic algorithm is developed.The solution framework is validated by the simulation environment referring to the Fort-class carrier,exhibiting higher sortie efficiency when compared to existing strategies.And animation of the simulation results is available at www.bilibili.com/video/BV14t421A7Tt/.The study presents a promising supporting technique for autonomous flight deck operation in the foreseeable future,and can be easily extended to other supporting scenarios,e.g.,ammunition delivery and aircraft maintenance.展开更多
Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries(PLIBs),while there is always a request on fast carrier transport in electrochemical active photocathodes.P...Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries(PLIBs),while there is always a request on fast carrier transport in electrochemical active photocathodes.Present work proposes a general approach of creating bulk heterojunction to boost the carrier mobility of photocathodes by simply laser assisted embedding of plasmonic nanocrystals.When employed in PLIBs,it was found effective for synchronously enhanced photocharge separation and transport in light charging process.Additionally,experimental photon spectroscopy,finite difference time domain method simulation and theoretical analyses demonstrate that the improved carrier dynamics are driven by the plasmonic-induced hot electron injection from metal to TiO_(2),as well as the enhanced conductivity in TiO2 matrix due to the formation of oxygen vacancies after Schottky contact.Benefiting from these merits,several benchmark values in performance of TiO2-based photocathode applied in PLIBs are set,including the capacity of 276 mAh g^(−1) at 0.2 A g^(−1) under illumination,photoconversion efficiency of 1.276%at 3 A g^(−1),less capacity and Columbic efficiency loss even through 200 cycles.These results exemplify the potential of the bulk heterojunction strategy in developing highly efficient and stable photoassisted energy storage systems.展开更多
The charge carrier transport and recombination dynamics in the quantum dots-based light-emitting diodes(QLEDs)featuring multiple emitting layers(M-EMLs)has a great impact on the device performance.In this work,QLEDs b...The charge carrier transport and recombination dynamics in the quantum dots-based light-emitting diodes(QLEDs)featuring multiple emitting layers(M-EMLs)has a great impact on the device performance.In this work,QLEDs based on M-EMLs separated by polyethyleneimine ethoxylated(PEIE)layer with different stacking sequences of blue(B),green(G),and red(R)QDs layer were used to intuitively explore the injection,transportation and recombination processes of the charge carriers in QLEDs by using the time-resolved electroluminescence(TrEL)spectra.From the TrEL spectra mea-surements,green and red emissions were obtained first in the QLEDs with the EMLs sequences of G/PEIE/B/PEIE/R and B/PEIE/R/PEIE/G along the direction of light emission,respectively.While the QLEDs adopt EMLs sequences of B/PEIE/G/PEIE/R,the blue,green and red emissions were obtained nearly at the same time.The above phenomenon can be attributed to different charge carrier transmission and radiation recombination process in the EMLs due to different valence band offsets and conduction band offsets between R-,G-and B-QDs by using different sequences of EMLs.White emission with coordi-nates of(0.31,0.31)and correlated color temperature(CCT)of 5916 K was obtained in the QLEDs with the EMLs se-quences of B/PEIE/G/PEIE/R,which can be attributed to the relative uniform emission of B-,G-and R-QDs due to the effec-tive injection and radiation recombination of charge carriers in each of the EMLs.The above results have great significance for further understanding and improving the performance of QLEDs with M-EMLs.展开更多
Nanolipid carriers and traditional emulsion containing chemical sunscreens were prepared using emulsification combined with ultrasonic technology.The nanolipid carriers showed superior performance in sunscreen encapsu...Nanolipid carriers and traditional emulsion containing chemical sunscreens were prepared using emulsification combined with ultrasonic technology.The nanolipid carriers showed superior performance in sunscreen encapsulation,slow release and skin impermeability,and provided an excellent nanolipid slow-release encapsulation system for sunscreens.As observed by transmission electron microscopy,the nanolipid carriers were spherical shape,with smooth surface and uniform distribution,and the particle sizes were mainly concentrated in the range of 230 to 250 nm without agglomeration.The nanolipid carriers significantly improved the sunscreen performance through the synergistic effect of scattering and chemical absorption,and showed better UV stability than traditional sunscreen,indicating their photoprotective function.In vitro release experiments showed that the nano-lipidic carriers exhibited better release control when loaded with octyl methoxycinnamate(OMC)and butylmethoxydibenzoylmethane(BDFM)sunscreens than traditional traditional emulsions,with the cumulative release rate of OMC in the nano-lipidic carriers decreasing by 17.17% to 30.24% within 12 hours,and that of BDFM decreasing by 26.67% to 44.67%.26.67% to 44.16%.The results of the in vitro permeation experiment further confirmed that the nanolipid carriers could effectively encapsulate the sunscreens and prevent them from penetrating the skin barrier,thus reducing the skin irritation.Compared with traditional traditional emulsion,the cumulative penetration of OMC in nanostructured lipid carriers was 2.24μg/cm^(2)in 4 hours,while the cumulative penetration was reduced by 68.05%.The cumulative penetration of BDFM in the nanostructured lipid carrier was 3.24μg/cm^(2),with a 64.04%reduction in cumulative penetration.展开更多
There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresse...There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresses carrier leakage by inserting n-Ga_(0.55)In_(0.45)P and p-GaAs_(0.6)P_(0.4) between barriers and waveguide layers,respectively,to modulate the energy band structure and to increase the height of barrier.The results show that the leakage current density reduces by 87.71%,compared to traditional structure.The nonradiative recombination current density of novel structure reduces to 37.411 A/cm^(2),and the output power reaches 12.80 W with wall-plug efficiency of 78.24%at an injection current density 5 A/cm^(2) at room temperature.In addition,the temperature drift coefficient of center wavelength is 0.206 nm/℃at the temperature range from 5℃to 65℃,and the slope of fitted straight line of threshold current with temperature variation is 0.00113.The novel epitaxial structure provides a theoretical basis for achieving high-power laser diode.展开更多
Introduction: Sickle cell disease is one of the most common autosomal recessive inherited diseases. Its prevalence is increasing due to the perpetuity of carriers of the trait who are able to marry. Women aged 18 to 3...Introduction: Sickle cell disease is one of the most common autosomal recessive inherited diseases. Its prevalence is increasing due to the perpetuity of carriers of the trait who are able to marry. Women aged 18 to 35 years constitute the most reproductive age group. This study was conducted with the aim of determining the prevalence of sickle cell trait among women aged 18 to 35 years and the attitude of women carriers towards the choice of a carrier spouse. Materials and methods: This was a cross-sectional descriptive study with analytical aims conducted from March to September 2024 in Kisangani. A total of 215 women aged 18 to 35 years presented for screening for sickle cell trait. This study described the following parameters: Sociodemographic data (age, level of education, socioeconomic level, marital status), obstetric and medical history (obstetric formula, sickle cell disease, high blood pressure, diabetes mellitus, asthma), knowledge of sickle cell disease (etiological classification, transmission, prevention, high-risk marriages, clinical manifestations, progression of the disease), attitude of the woman in relation to the choice of an AS spouse, as well as the reasons justifying each attitude. Results: The prevalence of sickle cell trait was 23.7% (51/215). A total of 64.3% of respondents had accepted the choice of spouse before confirmation of carrier status and 73.8% had refused after confirmation of carrier status. Choice was significantly related to age (p-value = 0.027), occupation (p-value = 0.015), parity (p-value = 0.039) and gesture (p-value = 0.034) before test. The ignorance of the union at risk was associated with the risk (p = 0.005;OR: 9.10;CI 95%: 2.03 - 4.81) of accepting the choice of a spouse carrying the trait. Conclusion: The prevalence of sickle cell trait among women aged 18 to 35 years in Kisangani remains within the limits of that of the general population. The choice of a spouse carrying sickle cell trait is associated with the woman’s age, her profession, parity, gestation and her knowledge about high-risk unions. Screening campaigns and health education sessions enable women carrying sickle cell trait to make a wise choice.展开更多
This study investigates the crystal structure,microstructure,electronic,thermal transport properties,and thermoelectric performance ofα-MgAgSb synthesized through various ball milling techniques.Variations in synthes...This study investigates the crystal structure,microstructure,electronic,thermal transport properties,and thermoelectric performance ofα-MgAgSb synthesized through various ball milling techniques.Variations in synthesis methods can significantly impact thermoelectric performance.Our findings indicate that impurity phases,particularly the secondary phase Ag_(3)Sb,hinder grain growth and decrease carrier mobility.By systematically adjusting milling conditions,the increased grain size resulting from the suppression of impurity formation improves charge carrier mobility and enhances the power factor.Low-temperature resistivity analysis reveals distinct scattering mechanisms influenced by impurity levels.α-MgAgSb with a tiny content of Sb primarily exhibits electron-electron scattering,whereas higher impurity levels introduce both electron-electron and electron-phonon scattering.Additionally,thermal conductivity analysis using three Effective Medium Theory(EMT)methods shows that the distribution of Ag_(3)Sb increases interfacial resistance.The maximum zT value of 1.36 was achieved in a compound with anα-MgAgSb to Sb ratio of 99%:1%.展开更多
Defects at the grain boundaries(GBs)of perovskite film highly restrict both the efficiency and stability of perovskite solar cells(PSCs).Herein,organic small molecules of butanedioic acid(BA)and acetylenedicarboxylic ...Defects at the grain boundaries(GBs)of perovskite film highly restrict both the efficiency and stability of perovskite solar cells(PSCs).Herein,organic small molecules of butanedioic acid(BA)and acetylenedicarboxylic acid(AA),containing two carbonyl(C=O)groups and different core-units,were incorporated into perovskite as additives for PSCs application.Thanks to the strong coordination interaction between C=O group and under-coordinated Pb^(2+),the additives can effectively passivate film defects and regulate the perovskite crystallization,yielding high-quality perovskite films with lower defect densities.More importantly,the additives can efficiently regulate the charge transport behaviors in PSCs.Benefiting from the defects passivation and the regulation of charge carrier dynamics,the BA and AA-treaded PSCs show the power conversion efficiencies of 21.52%and 20.50%,which are higher than that of the control device(19.41%).Besides,the optimal devices exhibit a remarkable enhanced long-term stability and moisture tolerance compared to the pristine devices.Furthermore,the transient absorption spectrum reveals the mechanism of enhanced photovoltaic performances,attributing to the improvement of charge transport capability at the perovskite/Spiro-OMeTAD interfaces.This work affords a promising strategy to improve the efficiency and stability of PSCs through regulating the charge-carrier dynamic process in perovskite film.展开更多
High-mobility semiconductor nanotubes have demonstrated great potential for applications in high-speed transistors,single-charge detection,and memory devices.Here we systematically investigated the electronic properti...High-mobility semiconductor nanotubes have demonstrated great potential for applications in high-speed transistors,single-charge detection,and memory devices.Here we systematically investigated the electronic properties of single-walled boron antimonide(BSb)nanotubes using first-principles calculations.We observed that rolling the hexagonal boron antimonide monolayer into armchair(ANT)and zigzag(ZNT)nanotubes induces compression and wrinkling effects,significantly modifying the band structures and carrier mobilities through band folding andπ^(*)-σ^(*)hybridization.As the chiral index increases,the band gap and carrier mobility of ANTs decrease monotonically,where electron mobility consistently exceeds hole mobility.In contrast,ZNTs exhibit a more complex trend:the band gap first increases and then decreases,and the carrier mobility displays oscillatory behavior.In particular,both ANTs and ZNTs could exhibit significantly higher carrier mobilities compared to hexagonal monolayer and zinc-blende BSb,reaching 10^(-3)-10^(-7) cm^(-2)·V^(-1)·s^(-1).Our findings highlight strong curvature-induced modifications in the electronic properties of single-walled BSb nanotubes,demonstrating the latter as a promising candidate for high-performance electronic devices.展开更多
Recovery is a crucial supporting process for carrier aircraft,where a reasonable landing scheduling is expected to guide the fleet landing safely and quickly.Currently,there is little research on this topic,and most o...Recovery is a crucial supporting process for carrier aircraft,where a reasonable landing scheduling is expected to guide the fleet landing safely and quickly.Currently,there is little research on this topic,and most of it neglects potential influence factors,leaving the corresponding supporting efficiency questionable.In this paper,we study the landing scheduling problem for carrier aircraft considering the effects of bolting and aerial refueling.Based on the analysis of recovery mode involving the above factors,two types of primary constraints(i.e.,fuel constraint and wake interval constraint)are first described.Then,taking the landing sequencing as decision variables,a combinatorial optimization model with a compound objective function is formulated.Aiming at an efficient solution,an improved firefly algorithm is designed by integrating multiple evolutionary operators.In addition,a dynamic replanning mechanism is introduced to deal with special situations(i.e.,the occurrence of bolting and fuel shortage),where the high efficiency of the designed algorithm facilitates the online scheduling adjustment within seconds.Finally,numerical simulations with sufficient and insufficient fuel cases are both carried out,highlighting the necessity to consider bolting and aerial refueling during the planning procedure.Simulation results reveal that a higher bolting probability,as well as extra aerial refueling operations caused by fuel shortage,will lead to longer recovery complete time.Meanwhile,due to the strong optimum-seeking capability and solution efficiency of the improved algorithm,adaptive scheduling can be generated within milliseconds to deal with special situations,significantly improving the safety and efficiency of the recovery process.An animation is accessible at bilibili.com/video/BV1QprKY2EwD.展开更多
A minority carrier lifetime of 25.46 μs in a P-type 4H-SiC epilayer has been attained through sequential thermal oxidation and hydrogen annealing. Thermal oxidation can enhance the minority carrier lifetime in the 4H...A minority carrier lifetime of 25.46 μs in a P-type 4H-SiC epilayer has been attained through sequential thermal oxidation and hydrogen annealing. Thermal oxidation can enhance the minority carrier lifetime in the 4H-SiC epilayer by reducing carbon vacancies. However, this process also generates carbon clusters with limited diffusivity and contributes to the enlargement of surface pits on the 4H-SiC. High-temperature hydrogen annealing effectively reduces stacking fault and dislocation density. Moreover, electron spin resonance analysis indicates a significant reduction in carbon vacancy defects after hydrogen annealing. The mechanisms of the elimination of carbon vacancies by hydrogen annealing include the decomposition of carbon clusters formed during thermal oxidation and the low-pressure selective etching by hydrogen,which increases the carbon content on the 4H-SiC surface and facilitates carbon diffusion. Consequently, the combination of thermal oxidation and hydrogen annealing eliminates carbon vacancies more effectively, substantially enhancing the minority carrier lifetime in P-type 4H-SiC. This improvement is advantageous for the application of high-voltage SiC bipolar devices.展开更多
The mixing injection of natural gas and pulverized coal into the blast furnaces shows a promising technological approach in the context of global carbon reduction initiatives.Carrier gas and coal pass through the air ...The mixing injection of natural gas and pulverized coal into the blast furnaces shows a promising technological approach in the context of global carbon reduction initiatives.Carrier gas and coal pass through the air inlet of coal lance,and the characteristics of carrier gas affect the flow in the air inlet and the combustion efficiency of coal,so it is very important to study the change of carrier gas charac-teristics in the lower part of blast furnace.By means of numerical simulation,the influence of carrier gas characteristics(injection rate,composition,and temperature)on the mixed combustion of natural gas(NG)and pulverized coal in the tuyere raceway of Russian blast furnace was analyzed.When N_(2) is used as carrier gas,the injection rate of carrier gas is reduced from 4000 to 2000 m3/h,the average tuy-ere temperature is increased(1947.42 to 1963.30 K),the mole fractions of CO and H_(2) are increased,and the burnout rate of pulverized coal is decreased.Increasing the carrier gas temperature is helpful to improve the burnout of pulverized coal.For every 20 K increase of carrier gas temperature,the average temperature in the raceway increases by 20.6 K,which promotes the release and combustion of volat-iles,but the increase of carrier gas temperature from 373 to 393 K only leads to 1.16%burnout change.Considering the transportation characteristics of pulverized coal,it is suggested that the carrier gas temperature should be kept at about 373 K to obtain the best perform-ance.It is worth noting that when air is used as carrier gas,the burnout rate of pulverized coal is increased by 2.69%compared with N_(2).展开更多
The 2D/3D heterojunction perovskites have garnered increasing attention due to their exceptional moisture and thermal stability.However,few works have paid attention to the influence of the subsequent change process o...The 2D/3D heterojunction perovskites have garnered increasing attention due to their exceptional moisture and thermal stability.However,few works have paid attention to the influence of the subsequent change process of 2D/3D heterojunction PSC on the stability of PSCs.Moreover,the evolution of the interface and carrier dynamic behavior of the 2D/3D perovskite films with long-term operation has not been systematically developed befo re.In this work,the effects of 2D/3 D heterojunction evolution on the interface of perovskite films and different carrier dynamics during 2D/3D evolution are systematically analyzed for the first time.The decomposition of 2D/3D heterojunction in the perovskite film will have a certain impact on the surface and carrier dynamics behavior of perovskite.During the evolution of 2D/3D heterojunction,PbI_(2)crystals will appear,which will improve the interfacial energy level matching between the electron transport layer and perovskite film.With a long evolution time,some holes will appear on the surface of perovskite film.The open circuit voltage(V_(OC))of PSCs increased from 1.14 to1.18 V and the PCE increased to 23.21%after 300 h storage in the nitrogen atmosphere,and maintained 89%initial performance for with 3000 h stability test in N_(2)box.This discovery has a significant role in promoting the development of inverted heterojunction PSCs and constructing the revolution mechanism of charge carrier dynamic.展开更多
Dengue is a mosquito-borne disease that is rampant worldwide,with up to 70%of cases reported to be asymptomatic during epidemics.In this paper,a reaction-diffusion dengue model with asymptomatic carrier transmission i...Dengue is a mosquito-borne disease that is rampant worldwide,with up to 70%of cases reported to be asymptomatic during epidemics.In this paper,a reaction-diffusion dengue model with asymptomatic carrier transmission is investigated.We aim to study the existence,nonexistence and minimum wave speed of traveling wave solutions to the model.The results show that the existence and nonexistence of traveling wave solutions are fully determined by the threshold values,which are,the basic reproduction number R0 and critical wave speed c^(*)>0.Specifically,when R0>1 and the wave speed c≥c^(*),the existence of the traveling wave solution is obtained by using Schauder's fixed point theorem and Lyapunov functional.It is proven that the model has no nontrivial traveling wave solutions for R0≤1 or R0>1 and 0<c<c^(*)by employing comparison principle and limit theory.As a consequence,we conclude that the critical wave speed c^(*)is the minimum wave speed of the model.Finally,numerical simulations are carried out to illustrate the effects of several important parameters on the minimum wave speed.展开更多
Nitrogen-doped single-walled carbon nanohorns(N-SWCNHs)can serve as an effective carrier for platinum(Pt)catalysts,which has the potential to improve the electrocatalytic activity of oxygen reduction reaction(ORR)and ...Nitrogen-doped single-walled carbon nanohorns(N-SWCNHs)can serve as an effective carrier for platinum(Pt)catalysts,which has the potential to improve the electrocatalytic activity of oxygen reduction reaction(ORR)and the operation life of the catalyst.In this work,dahlia-like SWCNHs with N contents ranging from 2.1at%to 4.3at%are controllably synthesized via arc discharge and applied as a carrier of Pt nanoparticles(NPs),denoted as Pt/N-SWCNHs.Pt/N-SWCNHs-2:1(graphite and melamine with the mass ratio of 2:1)exhibits excellent electrocatalytic activity(onset potential=0.95 V).The half-wave potential of Pt/N-SWCNHs-2:1 is only reduced by 2 mV after 3000 cyclic voltammetry cycles.This can be attributed to the enhanced dispersion of Pt NPs and the strong electronic interaction between the N-SWCNHs and Pt,facilitated by the optimal nitrogen doping level.The results of this work offer important perspectives on the design and enhancement of Pt-based electrocatalysts for ORR applications,highlighting the critical role of the nitrogen doping level in balancing the electrocatalytic activity and long-term stability.展开更多
Fe-doped CuCrO_(2) catalyst CuCr_(1-x)Fe_xO_(2) series were prepared by the sol-gel method with different Fe contents.The structure and properties of the catalysts were investigated by XRD(X-ray diffraction),SEM(scann...Fe-doped CuCrO_(2) catalyst CuCr_(1-x)Fe_xO_(2) series were prepared by the sol-gel method with different Fe contents.The structure and properties of the catalysts were investigated by XRD(X-ray diffraction),SEM(scanning electron microscope),and XPS(X-ray photoelectron spectroscopy)and the purification effect on NO_(x) and PM was measured through simulated emission experiments.The results indicate that CuCrO_(2) catalyst has good catalytic activity,the maximum NO_(x) conversion rate can be up to 28.15%,and the ignition temperature of PM can be reduced to 285℃.When the molecular ratio of Cr:Fe=9:1,the catalyst can achieve better catalytic effect,the maximum NO_(x) conversion rate will be up to 30.25%and the PM ignition temperature can be reduced to 280℃.In addition,the catalytic activity of catalyst supported on different carriers was also studied.The results show that catalyst on SiC foam ceramic carrier has better catalytic activity than that on cordierite honeycomb ceramic carrier.The maximum NO_(x) conversion of CuCrO_(2) and CuCr_(0.9)Fe_(0.1)O_(2) can be increased by 0.72%and 1.33%respectively,and the PM ignition temperature can be further reduced by 15 and 5℃respectively.展开更多
文摘Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.The published version showed“Hongzhen Chen”,whereas the correct spelling should be“Hongzheng Chen”.The correct author name has been provided in this Correction,and the original article[1]has been corrected.
基金supported by the National Key Research and Development Program of China (Grant No.2023YFF0719200)the National Natural Science Foundation of China (Grant Nos.62322115,U24A20226,62588201,62435010,and 62335012)+2 种基金the 111 Project (Grant No.D18014)the Key project supported by Science and Technology Commission Shanghai Municipality (Grant No.YDZX20193100004960)Science and Technology Commission of Shanghai Municipality (Grant Nos.22JC1400200 and 21S31907400)。
文摘Surface states are expected to play a key role in broadband terahertz(THz) emitters, where photoexcited carrier distributions are confined within about 1 μm of the surface. Optical pump and THz probe spectroscopy was used to study the dynamics of nonequilibrium charge carriers in both textured and non-textured GaAs substrates.Our findings show that the textured surface acts as an antireflective layer, greatly boosting the infrared pump laser's coupling efficiency into the semi-insulating GaAs substrate. Additionally, texturing introduces a trapassisted recombination pathway, speeding up carrier relaxation and thus reducing Joule heating. Under the same pumping and bias field conditions, the coarse-textured GaAs photoconductive antenna shows nearly 7.85 times stronger THz emission amplitude than the non-textured device, along with improvement in signal-to-noise ratio.At a fixed bias field, higher pump power increases photogenerated carrier density, causing bias field screening and subsequent saturation of THz emission. At fixed pump power, when the bias field reaches ~2.5 kV/cm, both THz emission and photocurrent spectra show a clear kink, signaling intervalley scattering from the Γ valley to the L(X) valleys under high electric fields.
基金supported by the National Key R&D Program of China(No.2023YFB3809100)the Youth Fund Project of Grinm(No.SKHT10422023060280).
文摘Dibenzyltoluene(DBT)is a prospective liquid organic hydrogen carrier(LOHC)with low cost and high theoretical hydrogen storage capacity(6.2 wt%).However,the wide application of DBT is severely restricted by expensive noble catalysts.In this work,a new Mg-based metal hydride hydrogenation catalyst,which is composed of MgH_(2),Mg_(2)NiH_(4) and LaH_(3) micro-nano-particles.
基金supported by the National Key R&D Program of China (Grant No. 2024YFA1408502)the National Natural Science Foundation of China (Grant Nos. 92365102, 62027807, 12474107, and 12174383)+1 种基金the Chinese Academy of Sciences project for Yong Scientists in Basic Research (Grant No. YSBR-030)the Guangdong Basic and Applied Basic Research Foundation (Grant No. 2024A1515011600)。
文摘We investigate the carrier, phonon, and spin dynamics in the ferromagnetic semiconductor(In,Fe)Sb using ultrafast optical pump-probe spectroscopy. We discover two anomalies near T^(*)(~40 K) and T^(†)(~200 K) in the photoexcited carrier dynamics, which can be attributed to the electron-spin and spin-lattice scattering processes influenced by the magnetic phase transition and modifications in magnetic anisotropy. The magnetization change can be revealed by the dynamics of coherent acoustic phonon. We also observe abrupt changes in the photoinduced spin dynamics near T^(*)and T^(†), which not only illustrate the spin-related scatterings closely related to the long-range magnetic order, but also reveal the D'yakonov–Perel and Elliott–Yafet mechanisms dominating at temperatures below and above T^(†), respectively. Our findings provide important insights into the nonequilibrium properties of the photoexcited(In,Fe)Sb.
基金the financial support of the National Key Research and Development Plan(2021YFB3302501)the financial support of the National Natural Science Foundation of China(12102077)。
文摘Safe and efficient sortie scheduling on the confined flight deck is crucial for maintaining high combat effectiveness of the aircraft carrier.The primary difficulty exactly lies in the spatiotemporal coordination,i.e.,allocation of limited supporting resources and collision-avoidance between heterogeneous dispatch entities.In this paper,the problem is investigated in the perspective of hybrid flow-shop scheduling problem by synthesizing the precedence,space and resource constraints.Specifically,eight processing procedures are abstracted,where tractors,preparing spots,catapults,and launching are virtualized as machines.By analyzing the constraints in sortie scheduling,a mixed-integer planning model is constructed.In particular,the constraint on preparing spot occupancy is improved to further enhance the sortie efficiency.The basic trajectory library for each dispatch entity is generated and a delayed strategy is integrated to address the collision-avoidance issue.To efficiently solve the formulated HFSP,which is essentially a combinatorial problem with tightly coupled constraints,a chaos-initialized genetic algorithm is developed.The solution framework is validated by the simulation environment referring to the Fort-class carrier,exhibiting higher sortie efficiency when compared to existing strategies.And animation of the simulation results is available at www.bilibili.com/video/BV14t421A7Tt/.The study presents a promising supporting technique for autonomous flight deck operation in the foreseeable future,and can be easily extended to other supporting scenarios,e.g.,ammunition delivery and aircraft maintenance.
基金supported by the project of the National Natural Science Foundation of China(52202115 and 52172101)Guangdong Basic and Applied Basic Research Foundation(2024A1515012325)+2 种基金the Natural Science Foundation of Chongqing,China(CSTB2022NSCQ-MSX1085)the Shaanxi Science and Technology Innovation Team(2023-CXTD-44)the Fundamental Research Funds for the Central Universities(G2022KY0604).
文摘Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries(PLIBs),while there is always a request on fast carrier transport in electrochemical active photocathodes.Present work proposes a general approach of creating bulk heterojunction to boost the carrier mobility of photocathodes by simply laser assisted embedding of plasmonic nanocrystals.When employed in PLIBs,it was found effective for synchronously enhanced photocharge separation and transport in light charging process.Additionally,experimental photon spectroscopy,finite difference time domain method simulation and theoretical analyses demonstrate that the improved carrier dynamics are driven by the plasmonic-induced hot electron injection from metal to TiO_(2),as well as the enhanced conductivity in TiO2 matrix due to the formation of oxygen vacancies after Schottky contact.Benefiting from these merits,several benchmark values in performance of TiO2-based photocathode applied in PLIBs are set,including the capacity of 276 mAh g^(−1) at 0.2 A g^(−1) under illumination,photoconversion efficiency of 1.276%at 3 A g^(−1),less capacity and Columbic efficiency loss even through 200 cycles.These results exemplify the potential of the bulk heterojunction strategy in developing highly efficient and stable photoassisted energy storage systems.
文摘The charge carrier transport and recombination dynamics in the quantum dots-based light-emitting diodes(QLEDs)featuring multiple emitting layers(M-EMLs)has a great impact on the device performance.In this work,QLEDs based on M-EMLs separated by polyethyleneimine ethoxylated(PEIE)layer with different stacking sequences of blue(B),green(G),and red(R)QDs layer were used to intuitively explore the injection,transportation and recombination processes of the charge carriers in QLEDs by using the time-resolved electroluminescence(TrEL)spectra.From the TrEL spectra mea-surements,green and red emissions were obtained first in the QLEDs with the EMLs sequences of G/PEIE/B/PEIE/R and B/PEIE/R/PEIE/G along the direction of light emission,respectively.While the QLEDs adopt EMLs sequences of B/PEIE/G/PEIE/R,the blue,green and red emissions were obtained nearly at the same time.The above phenomenon can be attributed to different charge carrier transmission and radiation recombination process in the EMLs due to different valence band offsets and conduction band offsets between R-,G-and B-QDs by using different sequences of EMLs.White emission with coordi-nates of(0.31,0.31)and correlated color temperature(CCT)of 5916 K was obtained in the QLEDs with the EMLs se-quences of B/PEIE/G/PEIE/R,which can be attributed to the relative uniform emission of B-,G-and R-QDs due to the effec-tive injection and radiation recombination of charge carriers in each of the EMLs.The above results have great significance for further understanding and improving the performance of QLEDs with M-EMLs.
文摘Nanolipid carriers and traditional emulsion containing chemical sunscreens were prepared using emulsification combined with ultrasonic technology.The nanolipid carriers showed superior performance in sunscreen encapsulation,slow release and skin impermeability,and provided an excellent nanolipid slow-release encapsulation system for sunscreens.As observed by transmission electron microscopy,the nanolipid carriers were spherical shape,with smooth surface and uniform distribution,and the particle sizes were mainly concentrated in the range of 230 to 250 nm without agglomeration.The nanolipid carriers significantly improved the sunscreen performance through the synergistic effect of scattering and chemical absorption,and showed better UV stability than traditional sunscreen,indicating their photoprotective function.In vitro release experiments showed that the nano-lipidic carriers exhibited better release control when loaded with octyl methoxycinnamate(OMC)and butylmethoxydibenzoylmethane(BDFM)sunscreens than traditional traditional emulsions,with the cumulative release rate of OMC in the nano-lipidic carriers decreasing by 17.17% to 30.24% within 12 hours,and that of BDFM decreasing by 26.67% to 44.67%.26.67% to 44.16%.The results of the in vitro permeation experiment further confirmed that the nanolipid carriers could effectively encapsulate the sunscreens and prevent them from penetrating the skin barrier,thus reducing the skin irritation.Compared with traditional traditional emulsion,the cumulative penetration of OMC in nanostructured lipid carriers was 2.24μg/cm^(2)in 4 hours,while the cumulative penetration was reduced by 68.05%.The cumulative penetration of BDFM in the nanostructured lipid carrier was 3.24μg/cm^(2),with a 64.04%reduction in cumulative penetration.
文摘There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresses carrier leakage by inserting n-Ga_(0.55)In_(0.45)P and p-GaAs_(0.6)P_(0.4) between barriers and waveguide layers,respectively,to modulate the energy band structure and to increase the height of barrier.The results show that the leakage current density reduces by 87.71%,compared to traditional structure.The nonradiative recombination current density of novel structure reduces to 37.411 A/cm^(2),and the output power reaches 12.80 W with wall-plug efficiency of 78.24%at an injection current density 5 A/cm^(2) at room temperature.In addition,the temperature drift coefficient of center wavelength is 0.206 nm/℃at the temperature range from 5℃to 65℃,and the slope of fitted straight line of threshold current with temperature variation is 0.00113.The novel epitaxial structure provides a theoretical basis for achieving high-power laser diode.
文摘Introduction: Sickle cell disease is one of the most common autosomal recessive inherited diseases. Its prevalence is increasing due to the perpetuity of carriers of the trait who are able to marry. Women aged 18 to 35 years constitute the most reproductive age group. This study was conducted with the aim of determining the prevalence of sickle cell trait among women aged 18 to 35 years and the attitude of women carriers towards the choice of a carrier spouse. Materials and methods: This was a cross-sectional descriptive study with analytical aims conducted from March to September 2024 in Kisangani. A total of 215 women aged 18 to 35 years presented for screening for sickle cell trait. This study described the following parameters: Sociodemographic data (age, level of education, socioeconomic level, marital status), obstetric and medical history (obstetric formula, sickle cell disease, high blood pressure, diabetes mellitus, asthma), knowledge of sickle cell disease (etiological classification, transmission, prevention, high-risk marriages, clinical manifestations, progression of the disease), attitude of the woman in relation to the choice of an AS spouse, as well as the reasons justifying each attitude. Results: The prevalence of sickle cell trait was 23.7% (51/215). A total of 64.3% of respondents had accepted the choice of spouse before confirmation of carrier status and 73.8% had refused after confirmation of carrier status. Choice was significantly related to age (p-value = 0.027), occupation (p-value = 0.015), parity (p-value = 0.039) and gesture (p-value = 0.034) before test. The ignorance of the union at risk was associated with the risk (p = 0.005;OR: 9.10;CI 95%: 2.03 - 4.81) of accepting the choice of a spouse carrying the trait. Conclusion: The prevalence of sickle cell trait among women aged 18 to 35 years in Kisangani remains within the limits of that of the general population. The choice of a spouse carrying sickle cell trait is associated with the woman’s age, her profession, parity, gestation and her knowledge about high-risk unions. Screening campaigns and health education sessions enable women carrying sickle cell trait to make a wise choice.
基金financially supported by JST Mirai Program(No.JPMJMI19A1).
文摘This study investigates the crystal structure,microstructure,electronic,thermal transport properties,and thermoelectric performance ofα-MgAgSb synthesized through various ball milling techniques.Variations in synthesis methods can significantly impact thermoelectric performance.Our findings indicate that impurity phases,particularly the secondary phase Ag_(3)Sb,hinder grain growth and decrease carrier mobility.By systematically adjusting milling conditions,the increased grain size resulting from the suppression of impurity formation improves charge carrier mobility and enhances the power factor.Low-temperature resistivity analysis reveals distinct scattering mechanisms influenced by impurity levels.α-MgAgSb with a tiny content of Sb primarily exhibits electron-electron scattering,whereas higher impurity levels introduce both electron-electron and electron-phonon scattering.Additionally,thermal conductivity analysis using three Effective Medium Theory(EMT)methods shows that the distribution of Ag_(3)Sb increases interfacial resistance.The maximum zT value of 1.36 was achieved in a compound with anα-MgAgSb to Sb ratio of 99%:1%.
基金National Natural Science Foundation of China(No.22065038)High-Level Talents Introduction in Yunnan Province(No.C619300A010)+3 种基金the Fund for Excellent Young Scholars of Yunnan(No.202001AW070008)Spring City Plan:the Highlevel Talent Promotion and Training Project of Kunming(No.2022SCP005)for financial supportthe support from the Postdoctoral Research Foundation of Yunnan University(No.W8223004)the Postdoctoral Foundation of Department of Human Resources and Social Security of Yunnan Province(No.C615300504046)。
文摘Defects at the grain boundaries(GBs)of perovskite film highly restrict both the efficiency and stability of perovskite solar cells(PSCs).Herein,organic small molecules of butanedioic acid(BA)and acetylenedicarboxylic acid(AA),containing two carbonyl(C=O)groups and different core-units,were incorporated into perovskite as additives for PSCs application.Thanks to the strong coordination interaction between C=O group and under-coordinated Pb^(2+),the additives can effectively passivate film defects and regulate the perovskite crystallization,yielding high-quality perovskite films with lower defect densities.More importantly,the additives can efficiently regulate the charge transport behaviors in PSCs.Benefiting from the defects passivation and the regulation of charge carrier dynamics,the BA and AA-treaded PSCs show the power conversion efficiencies of 21.52%and 20.50%,which are higher than that of the control device(19.41%).Besides,the optimal devices exhibit a remarkable enhanced long-term stability and moisture tolerance compared to the pristine devices.Furthermore,the transient absorption spectrum reveals the mechanism of enhanced photovoltaic performances,attributing to the improvement of charge transport capability at the perovskite/Spiro-OMeTAD interfaces.This work affords a promising strategy to improve the efficiency and stability of PSCs through regulating the charge-carrier dynamic process in perovskite film.
基金Project supported by the National Key R&D Program of China(Grant Nos.2022YFA1402503,2023YFA1406200,2023YFB3003001)the National Natural Science Foundation of China(Grant Nos.12074138 and 12047530)+2 种基金the Interdisciplinary Integration and Innovation Project of JLUFundamental Research Funds for the Central Universitiesthe Program for JLU Science and Technology Innovative Research Team(JLUSTIRT)。
文摘High-mobility semiconductor nanotubes have demonstrated great potential for applications in high-speed transistors,single-charge detection,and memory devices.Here we systematically investigated the electronic properties of single-walled boron antimonide(BSb)nanotubes using first-principles calculations.We observed that rolling the hexagonal boron antimonide monolayer into armchair(ANT)and zigzag(ZNT)nanotubes induces compression and wrinkling effects,significantly modifying the band structures and carrier mobilities through band folding andπ^(*)-σ^(*)hybridization.As the chiral index increases,the band gap and carrier mobility of ANTs decrease monotonically,where electron mobility consistently exceeds hole mobility.In contrast,ZNTs exhibit a more complex trend:the band gap first increases and then decreases,and the carrier mobility displays oscillatory behavior.In particular,both ANTs and ZNTs could exhibit significantly higher carrier mobilities compared to hexagonal monolayer and zinc-blende BSb,reaching 10^(-3)-10^(-7) cm^(-2)·V^(-1)·s^(-1).Our findings highlight strong curvature-induced modifications in the electronic properties of single-walled BSb nanotubes,demonstrating the latter as a promising candidate for high-performance electronic devices.
基金the financial support of the National Natural Science Foundation of China(12102077,12161076)the Natural Science and Technology Program of Liaoning Province(2023-BS-061).
文摘Recovery is a crucial supporting process for carrier aircraft,where a reasonable landing scheduling is expected to guide the fleet landing safely and quickly.Currently,there is little research on this topic,and most of it neglects potential influence factors,leaving the corresponding supporting efficiency questionable.In this paper,we study the landing scheduling problem for carrier aircraft considering the effects of bolting and aerial refueling.Based on the analysis of recovery mode involving the above factors,two types of primary constraints(i.e.,fuel constraint and wake interval constraint)are first described.Then,taking the landing sequencing as decision variables,a combinatorial optimization model with a compound objective function is formulated.Aiming at an efficient solution,an improved firefly algorithm is designed by integrating multiple evolutionary operators.In addition,a dynamic replanning mechanism is introduced to deal with special situations(i.e.,the occurrence of bolting and fuel shortage),where the high efficiency of the designed algorithm facilitates the online scheduling adjustment within seconds.Finally,numerical simulations with sufficient and insufficient fuel cases are both carried out,highlighting the necessity to consider bolting and aerial refueling during the planning procedure.Simulation results reveal that a higher bolting probability,as well as extra aerial refueling operations caused by fuel shortage,will lead to longer recovery complete time.Meanwhile,due to the strong optimum-seeking capability and solution efficiency of the improved algorithm,adaptive scheduling can be generated within milliseconds to deal with special situations,significantly improving the safety and efficiency of the recovery process.An animation is accessible at bilibili.com/video/BV1QprKY2EwD.
基金Project supported by the National Key Research and Development Program of China (Grant Nos. 2023YFB3609500 and 2023YFB3609502)the National Natural Science Foundation of China (Grant No. 62274137)+1 种基金the Natural Science Foundation of Jiangxi Province, China (Grant No. 20232BAB202043)the Science and Technology Project of Fujian Province of China (Grant No. 2020I0001)。
文摘A minority carrier lifetime of 25.46 μs in a P-type 4H-SiC epilayer has been attained through sequential thermal oxidation and hydrogen annealing. Thermal oxidation can enhance the minority carrier lifetime in the 4H-SiC epilayer by reducing carbon vacancies. However, this process also generates carbon clusters with limited diffusivity and contributes to the enlargement of surface pits on the 4H-SiC. High-temperature hydrogen annealing effectively reduces stacking fault and dislocation density. Moreover, electron spin resonance analysis indicates a significant reduction in carbon vacancy defects after hydrogen annealing. The mechanisms of the elimination of carbon vacancies by hydrogen annealing include the decomposition of carbon clusters formed during thermal oxidation and the low-pressure selective etching by hydrogen,which increases the carbon content on the 4H-SiC surface and facilitates carbon diffusion. Consequently, the combination of thermal oxidation and hydrogen annealing eliminates carbon vacancies more effectively, substantially enhancing the minority carrier lifetime in P-type 4H-SiC. This improvement is advantageous for the application of high-voltage SiC bipolar devices.
基金financially supported by the National Key R&D Program of China(No.2022YFE0208100)the Major Science and Technology Project of Xinjiang Uygur Autonomous Region,China(No.2022A01003)+1 种基金the Key Research and Development Plan of Anhui Province,China(No.202210700037)the National Natural Science Foundation of China(No.52274316).
文摘The mixing injection of natural gas and pulverized coal into the blast furnaces shows a promising technological approach in the context of global carbon reduction initiatives.Carrier gas and coal pass through the air inlet of coal lance,and the characteristics of carrier gas affect the flow in the air inlet and the combustion efficiency of coal,so it is very important to study the change of carrier gas charac-teristics in the lower part of blast furnace.By means of numerical simulation,the influence of carrier gas characteristics(injection rate,composition,and temperature)on the mixed combustion of natural gas(NG)and pulverized coal in the tuyere raceway of Russian blast furnace was analyzed.When N_(2) is used as carrier gas,the injection rate of carrier gas is reduced from 4000 to 2000 m3/h,the average tuy-ere temperature is increased(1947.42 to 1963.30 K),the mole fractions of CO and H_(2) are increased,and the burnout rate of pulverized coal is decreased.Increasing the carrier gas temperature is helpful to improve the burnout of pulverized coal.For every 20 K increase of carrier gas temperature,the average temperature in the raceway increases by 20.6 K,which promotes the release and combustion of volat-iles,but the increase of carrier gas temperature from 373 to 393 K only leads to 1.16%burnout change.Considering the transportation characteristics of pulverized coal,it is suggested that the carrier gas temperature should be kept at about 373 K to obtain the best perform-ance.It is worth noting that when air is used as carrier gas,the burnout rate of pulverized coal is increased by 2.69%compared with N_(2).
基金financial support provided by the Sichuan Science and Technology Program(No.2022NSFSC0226)Sichuan Science and Technology Program(No.2023ZYD0163)+6 种基金the Production-Education Integration Demonstration Project of Sichuan Provincethe Photovoltaic Industry Production-Education Integration Comprehensive Demonstration Base of Sichuan Province(Sichuan Financial Education[2022]No.106)China Tianfu Yongxing Laboratory Science and Technology Key Project(2023KJGG15)National Key Research and Development Program of China(2022YFB3803300)Beijing Natural Science Foundation(IS23037)the Department for Energy Security and Net Zero(project ID:NEXTCCUS)the ACT program(Accelerating CCS Technologies,Horizon2020 project NO.691712)。
文摘The 2D/3D heterojunction perovskites have garnered increasing attention due to their exceptional moisture and thermal stability.However,few works have paid attention to the influence of the subsequent change process of 2D/3D heterojunction PSC on the stability of PSCs.Moreover,the evolution of the interface and carrier dynamic behavior of the 2D/3D perovskite films with long-term operation has not been systematically developed befo re.In this work,the effects of 2D/3 D heterojunction evolution on the interface of perovskite films and different carrier dynamics during 2D/3D evolution are systematically analyzed for the first time.The decomposition of 2D/3D heterojunction in the perovskite film will have a certain impact on the surface and carrier dynamics behavior of perovskite.During the evolution of 2D/3D heterojunction,PbI_(2)crystals will appear,which will improve the interfacial energy level matching between the electron transport layer and perovskite film.With a long evolution time,some holes will appear on the surface of perovskite film.The open circuit voltage(V_(OC))of PSCs increased from 1.14 to1.18 V and the PCE increased to 23.21%after 300 h storage in the nitrogen atmosphere,and maintained 89%initial performance for with 3000 h stability test in N_(2)box.This discovery has a significant role in promoting the development of inverted heterojunction PSCs and constructing the revolution mechanism of charge carrier dynamic.
基金supported by the National Natural Science Foundation of China(12271317,11871316)。
文摘Dengue is a mosquito-borne disease that is rampant worldwide,with up to 70%of cases reported to be asymptomatic during epidemics.In this paper,a reaction-diffusion dengue model with asymptomatic carrier transmission is investigated.We aim to study the existence,nonexistence and minimum wave speed of traveling wave solutions to the model.The results show that the existence and nonexistence of traveling wave solutions are fully determined by the threshold values,which are,the basic reproduction number R0 and critical wave speed c^(*)>0.Specifically,when R0>1 and the wave speed c≥c^(*),the existence of the traveling wave solution is obtained by using Schauder's fixed point theorem and Lyapunov functional.It is proven that the model has no nontrivial traveling wave solutions for R0≤1 or R0>1 and 0<c<c^(*)by employing comparison principle and limit theory.As a consequence,we conclude that the critical wave speed c^(*)is the minimum wave speed of the model.Finally,numerical simulations are carried out to illustrate the effects of several important parameters on the minimum wave speed.
基金financially supported by the National Natural Science Foundation of China(Nos.12175089 and 12205127)the Key Research and Development Program of Yunnan Province,China(Nos.202301AU070064 and 202103AF140006)the Yunnan Industrial Innovative Talents Program for“Xingdian Talent Support Plan”,China(No.KKXY202252001).
文摘Nitrogen-doped single-walled carbon nanohorns(N-SWCNHs)can serve as an effective carrier for platinum(Pt)catalysts,which has the potential to improve the electrocatalytic activity of oxygen reduction reaction(ORR)and the operation life of the catalyst.In this work,dahlia-like SWCNHs with N contents ranging from 2.1at%to 4.3at%are controllably synthesized via arc discharge and applied as a carrier of Pt nanoparticles(NPs),denoted as Pt/N-SWCNHs.Pt/N-SWCNHs-2:1(graphite and melamine with the mass ratio of 2:1)exhibits excellent electrocatalytic activity(onset potential=0.95 V).The half-wave potential of Pt/N-SWCNHs-2:1 is only reduced by 2 mV after 3000 cyclic voltammetry cycles.This can be attributed to the enhanced dispersion of Pt NPs and the strong electronic interaction between the N-SWCNHs and Pt,facilitated by the optimal nitrogen doping level.The results of this work offer important perspectives on the design and enhancement of Pt-based electrocatalysts for ORR applications,highlighting the critical role of the nitrogen doping level in balancing the electrocatalytic activity and long-term stability.
基金Funded by National Natural Science Foundation of China(No.52494933)。
文摘Fe-doped CuCrO_(2) catalyst CuCr_(1-x)Fe_xO_(2) series were prepared by the sol-gel method with different Fe contents.The structure and properties of the catalysts were investigated by XRD(X-ray diffraction),SEM(scanning electron microscope),and XPS(X-ray photoelectron spectroscopy)and the purification effect on NO_(x) and PM was measured through simulated emission experiments.The results indicate that CuCrO_(2) catalyst has good catalytic activity,the maximum NO_(x) conversion rate can be up to 28.15%,and the ignition temperature of PM can be reduced to 285℃.When the molecular ratio of Cr:Fe=9:1,the catalyst can achieve better catalytic effect,the maximum NO_(x) conversion rate will be up to 30.25%and the PM ignition temperature can be reduced to 280℃.In addition,the catalytic activity of catalyst supported on different carriers was also studied.The results show that catalyst on SiC foam ceramic carrier has better catalytic activity than that on cordierite honeycomb ceramic carrier.The maximum NO_(x) conversion of CuCrO_(2) and CuCr_(0.9)Fe_(0.1)O_(2) can be increased by 0.72%and 1.33%respectively,and the PM ignition temperature can be further reduced by 15 and 5℃respectively.