Glycogen metabolism plays a key role in the development of hepatoellular carcinoma(HCC),but the function of glycogen metabolism genes in the tumor microenvironment(TME)is still to be elucidated.Single cell RNA-seq dat...Glycogen metabolism plays a key role in the development of hepatoellular carcinoma(HCC),but the function of glycogen metabolism genes in the tumor microenvironment(TME)is still to be elucidated.Single cell RNA-seq data were obtained from ten HCC tumor samples totaling 64,545 cells and 65 glycogen metabolism genes were analyzed bya nonnegative matrix factorization(NMF).The prognosis and immune response of new glycogen TME cell dusters were predicted by using HCC and immunotherapy cohorts from public databases.HOC single cell analysis was divided into fibroblasts,NT T cells,macrophages,endothelial clls,and B cells,which were separately divided into new cell clusters by glycogen metabolism gene annotation.Pseudo temporal trajectory analysis demonstrated the temporal differentiation trajectory of different glycogen subtype cell dusters.Cellular communication analysis revealed extensive interactions between endothelial cells with glycogen metabolizing TME cell.related subtypes and diferent glycogen subtype cell clusters.SCENIC analysis of transcription factors upstream of TME cell clusters with different glycogen metabolism.In addition,TME cell dusters of glycogen metabolism were found to be enriched in expression in CAF subtypes,CD8 depleted,M1,and M2 types.Bulk seq analysis showed the prognostic signifcance of glycogen metabolism.mediated TME cell dusters in HCC,while a significant immune response was found in the immunotherapy cohort in patients treated with immune checkpoint blockade(ICB),especially for CAFs,T cells,and macrophages In summary,our study reveals for the first time that glycogen metabolism mediates intercellular communication in the hepatocellular carcinoma microenvironment while elucidating the anti-tumor mechanisms and immune prognostic responses of different subtypes of cell dusters.展开更多
Transparent microwave absorbers that exhibit high optical transmittance and microwave absorption capability are ideal,although having a fixed absorption performance limits their applicability.Here,a simple,transparent...Transparent microwave absorbers that exhibit high optical transmittance and microwave absorption capability are ideal,although having a fixed absorption performance limits their applicability.Here,a simple,transparent,and thermally tunable microwave absorber is proposed,based on a patterned vanadium dioxide(VO_(2))film.Numerical calculations and experiments demonstrate that the proposed VO_(2)absorber has a high optical transmittance of 84.9%at 620 nm;its reflection loss at 15.06 GHz can be thermally tuned from–4.257 to–60.179 dB,and near-unity absorption is achieved at 523.750 K.Adjusting only the patterned VO_(2)film duty cycle can change the temperature of near-unity absorption.Our VO_(2)absorber has a simple composition,a high optical transmittance,a thermally tunable microwave absorption performance,a large modulation depth,and an adjustable temperature tuning range,making it promising for application in tunable sensors,thermal emitters,modulators,thermal imaging,bolometers,and photovoltaic devices.展开更多
Separators or electrolyte membranes are recognized as the key components to guarantee ion transport in rechargeable batteries.However,the ever-growing applications of the battery systems for diverse working environmen...Separators or electrolyte membranes are recognized as the key components to guarantee ion transport in rechargeable batteries.However,the ever-growing applications of the battery systems for diverse working environments bring new challenges,which require advanced battery membranes with high thermal stability,excellent mechanical strength,high voltage tolerance,etc.Therefore,it is highly desirable to design novel methods/concepts to solve the current challenges for battery membranes through understanding the mechanism of novel phenomena and electrochemical reactions in battery systems working under unconventional conditions.Recently,the new emerging Janus separators or electrolyte membranes with two or more distinct chemical/physical properties arising from their asymmetric structure and composition,are promising to address the above challenges via rational design of their targeted functionalities.To this end,in this review,we first briefly cover the current challenges of the traditional battery membrane for battery devices working in unconventional conditions.Then,the state-of-art developments of the rational design of Janus membranes to overcome the above challenges for diverse battery applications are summarized.Finally,we outline these latest developments,challenges,and future potential directions of the Janus membrane.Our review is aimed to provide basic guidance for developing functional separators or electrolyte membranes for advanced batteries.展开更多
[Objectives]This study was conducted to investigate the main factors affecting the aerobial plate count in raw milk.[Methods]Drinking water,medicated baths and raw milk under different storage and transportation condi...[Objectives]This study was conducted to investigate the main factors affecting the aerobial plate count in raw milk.[Methods]Drinking water,medicated baths and raw milk under different storage and transportation conditions were detected for the values of aerobial plate count to analyze their effects on the aerobial plate count in raw milk.[Results]Disinfection of drinking water tanks could significantly reduce the aerobial plate count in water.The use of medicated baths before and after milking could effectively reduce the aerobial plate count and had a significant bactericidal effect.The growth of microorganisms in raw milk stored below 4℃was relatively slow.Regularly disinfecting drinking water tanks and disinfecting nipples before and after milking could reduce the aerobial plate count in the tanks and nipples.After raw milk was extruded,the temperature should decrease to 0-4℃within 2 h,and the storage time should not exceed 48 h,which could effectively control the aerobial plate count in raw milk.[Conclusions]This study provides a reference for scientific control of the aerobial plate count in raw milk.展开更多
In this article, the nonlinear dynamic responses of sandwich functionally graded(FG) porous cylindrical shell embedded in elastic media are investigated. The shell studied here consists of three layers, of which the o...In this article, the nonlinear dynamic responses of sandwich functionally graded(FG) porous cylindrical shell embedded in elastic media are investigated. The shell studied here consists of three layers, of which the outer and inner skins are made of solid metal, while the core is FG porous metal foam. Partial differential equations are derived by utilizing the improved Donnell's nonlinear shell theory and Hamilton's principle. Afterwards, the Galerkin method is used to transform the governing equations into nonlinear ordinary differential equations, and an approximate analytical solution is obtained by using the multiple scales method. The effects of various system parameters,specifically, the radial load, core thickness, foam type, foam coefficient, structure damping,and Winkler-Pasternak foundation parameters on nonlinear internal resonance of the sandwich FG porous thin shells are evaluated.展开更多
The nonlinear vibration characteristics of the piezoelectric circular cylindrical nanoshells resting on an elastic foundation are analyzed. The small scale effect and thermo-electro-mechanical loading are taken into a...The nonlinear vibration characteristics of the piezoelectric circular cylindrical nanoshells resting on an elastic foundation are analyzed. The small scale effect and thermo-electro-mechanical loading are taken into account. Based on the nonlocal elasticity theory and Donnell's nonlinear shell theory, the nonlinear governing equations and the corresponding boundary conditions are derived by employing Hamilton's principle. Then,the Galerkin method is used to transform the governing equations into a set of ordinary differential equations, and subsequently, the multiple-scale method is used to obtain an approximate analytical solution. Finally, an extensive parametric study is conducted to examine the effects of the nonlocal parameter, the external electric potential, the temperature rise, and the Winkler-Pasternak foundation parameters on the nonlinear vibration characteristics of circular cylindrical piezoelectric nanoshells.展开更多
The Particle Velocity Sensor (PVS) is a kind of acoustic transducer which measures the particle velocity directly with figure-of-eight directivity. This paper proposes a near-field noise scanning technology based on t...The Particle Velocity Sensor (PVS) is a kind of acoustic transducer which measures the particle velocity directly with figure-of-eight directivity. This paper proposes a near-field noise scanning technology based on the research of PVS, pressure-particle velocity (P-U) probe, and its application in noise source identification. Firstly, the principle and characteristics of PVS are presented. Secondly, a P-U probe is designed on the basis of PVS development. Finally, the noise measurement experiment for a single source is arranged and conducted. The result shows that the proposed P-U probe performs well in near-field noise source identification and localization.展开更多
Composite cylindrical shells,as key components,are widely employed in large rotating machines.However,due to the frequency bifurcations and dense frequency spectra caused by rotation,the nonlinear vibration usually ha...Composite cylindrical shells,as key components,are widely employed in large rotating machines.However,due to the frequency bifurcations and dense frequency spectra caused by rotation,the nonlinear vibration usually has the behavior of complex multiple internal resonances.In addition,the varying temperature fields make the responses of the system further difficult to obtain.Therefore,the multiple internal resonances of composite cylindrical shells with porosities induced by rotation with varying temperature fields are studied in this paper.Three different types of the temperature fields,the Coriolis forces,and the centrifugal force are considered here.The Hamilton principle and the modified Donnell nonlinear shell theory are used to obtain the equilibrium equations of the system,which are transformed into the ordinary differential equations(ODEs)by the multi-mode Galerkin technique.Thereafter,the pseudo-arclength continuation method,which can identify the regions of instability,is introduced to obtain the numerical results.The detailed parametric analysis of the rotating composite shells is performed.Multiple internal resonances caused by the interaction between backward and forward wave modes and the energy transfer phenomenon are detected.Besides,the nonlinear amplitude-frequency response curves are different under different temperature fields.展开更多
A series of uniform single-phase spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors were prepared via a microwave hydrothermal method by using trisodium citrate dehydrate as surfactant.The phase structure,morphology an...A series of uniform single-phase spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors were prepared via a microwave hydrothermal method by using trisodium citrate dehydrate as surfactant.The phase structure,morphology and photoluminescence properties were measured by powder X-ray diffraction,scanning electron microscope and fluorescence spectrometer,respectively.The results show that uniform spherical microcrystals with diameters in the range of 2–4μm are obtained.And the phase and morphology of samples are not significantly changed by doping rare earth(RE^(3+))ions.Under the excitation wavelength of 356 and 365 nm,the samples BaWO 4:0.03Dy^(3+),yTm^(3+)can emit cold white light.In order to lower the correlated color temperature(CCT)to get a warm white light,the Eu^(3+)ions were doped into BaWO 4:0.03Dy^(3+),0.01Tm^(3+).Especially,under the excitation of 365 nm,BaWO 4:0.03Dy^(3+),0.01Tm^(3+),0.03Eu^(3+)phosphor shew a bright warm white light with color coordi-nate of(0.4013,0.3629)and CCT of 3288 K.Moreover,in the BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors,the energy transfer mechanism among Dy^(3+),Tm^(3+)and Eu^(3+)ions have been discussed and the change of electron structures have been calculated by first-principles calculations.The results shew that the uniform single-phase spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors could be favorable candidates in warm white LEDs.展开更多
Maneuvering flight substantially affects the dynamic behavior of rotors;particularly,such flight may cause rubbing between a rotor and stator,which is one of the most serious damages in aircraft engines.In this paper,...Maneuvering flight substantially affects the dynamic behavior of rotors;particularly,such flight may cause rubbing between a rotor and stator,which is one of the most serious damages in aircraft engines.In this paper,a nonlinear dynamic model for describing the dynamic characteristics of a rub-impact rotor system during maneuvering flight is established based on the Lagrange equations.Subsequently,numerical simulations employing the Newmark method are performed,delving into the detailed discussion of the influence of parameters such as rotational speed and maneuvering flight on the transient and steady-state responses of the rotor system.The effect mechanism of maneuver load and its coupling with rub impact is revealed.The results show that the impact response induced by maneuvering flight is more obvious in the subcritical state than in the supercritical state.The additional stiffness and damping are also induced;in particular,the additional damping has a coupling effect.Moreover,the rub impact imposes an additional constraint on the rotor system,thereby weakening the influence of the maneuver load and becoming the major factor that determines the dynamic behavior of the rotor system at high speeds.展开更多
Summary What is already known about this topic?Myopia has been identified as a significant emerging challenge and policy priority among children and adolescents in China by the Ministry of Education and seven other de...Summary What is already known about this topic?Myopia has been identified as a significant emerging challenge and policy priority among children and adolescents in China by the Ministry of Education and seven other departments.Limited research has been conducted to investigate the collective impact of outdoor time and other modifiable factors on the incidence of myopia.展开更多
Magnetorheological(MR)dampers show superior performance in reducing rotor vibration,but their high nonlinearity will cause nonsynchronous response,resulting in fatigue and instability of rotors.Herein,we are devoted t...Magnetorheological(MR)dampers show superior performance in reducing rotor vibration,but their high nonlinearity will cause nonsynchronous response,resulting in fatigue and instability of rotors.Herein,we are devoted to the investigation of the nonlinear characteristics of MR damper mounted on a flexible rotor.First,Reynolds equations with bilinear constitutive equations of MR fluid are employed to derive nonlinear oil film forces.Then,the Finite Element(FE)model of rotor system is developed,where the local nonlinear support forces produced by MR damper and its coupling effects with the rotor are considered.A hybrid numerical method is proposed to solve the nonlinear FE motion equations of the MR damper-rotor system.To validate the proposed model,a rotor test bench with two dual-coil MR dampers is constructed,upon which experimental studies on the dynamic characteristics of MR damper-rotor system are carried out.The effects of different system parameters,including rotational speed,excitation current and amount of unbalance,on nonlinear dynamic behaviors of MR damper-rotor system are evaluated.The results show that the system may appear chaos,jumping,and other complex nonlinear phenomena,and the level of the nonlinearity can be effectively alleviated by applying suitable excitation current and oil supply pressure.展开更多
Revealing the epitaxial growth mechanism and the interfacial coupling effect between oxide films will help to build a“structure-property”bridge for the design of microelectronic devices.Here,the epitaxial growth mec...Revealing the epitaxial growth mechanism and the interfacial coupling effect between oxide films will help to build a“structure-property”bridge for the design of microelectronic devices.Here,the epitaxial growth mechanism and the interfacial coupling in Bi_(0.5)Na_(0.5)TiO_(3)/SrTiO_(3)(BNT/STO)heterointerfaces are investigated by the aberration-corrected scanning transmission electron microscopy,which is synthesized by a hydrothermal method.The results illustrate that 4 mol/L NaOH leads to not only the epitaxial growth of the BNT film but also the mutual diffusion of elements.The uneven distribution of local elements in BNT films is observed and confirmed to impact the cation displacements of B-site and lattice distortion.However,the overall trend of B-site cation displacement at the BNT/STO heterointerfaces is dominated by the interfacial strain.Additionally,the oxygen octahedral tilt exhibits continuous tilt patterns of a^(0)a^(0)a^(0)-a−b^(0)c−-a^(0)a^(0)c−-a^(0)b−c−-a−b−c−from the substrate to BNT film due to the constraint of the substrate and presents a strong correlation with cation displacement.These results are helpful to understand the underlying atomic structures and physical properties of BNT epitaxial thin films.展开更多
Intrinsic image decomposition is an important and long-standing computer vision problem.Given an input image,recovering the physical scene properties is ill-posed.Several physically motivated priors have been used to ...Intrinsic image decomposition is an important and long-standing computer vision problem.Given an input image,recovering the physical scene properties is ill-posed.Several physically motivated priors have been used to restrict the solution space of the optimization problem for intrinsic image decomposition.This work takes advantage of deep learning,and shows that it can solve this challenging computer vision problem with high efficiency.The focus lies in the feature encoding phase to extract discriminative features for different intrinsic layers from an input image.To achieve this goal,we explore the distinctive characteristics of different intrinsic components in the high-dimensional feature embedding space.We define feature distribution divergence to efficiently separate the feature vectors of different intrinsic components.The feature distributions are also constrained to fit the real ones through a feature distribution consistency.In addition,a data refinement approach is provided to remove data inconsistency from the Sintel dataset,making it more suitable for intrinsic image decomposition.Our method is also extended to intrinsic video decomposition based on pixel-wise correspondences between adjacent frames.Experimental results indicate that our proposed network structure can outperform the existing state-of-the-art.展开更多
In this paper,we proposed an active metasurface in reflection manner that can generate reconfigurable OAM vortex beams with high purity in the X-band.The metasurface has a high reflectance of 0.94 and achieves a phase...In this paper,we proposed an active metasurface in reflection manner that can generate reconfigurable OAM vortex beams with high purity in the X-band.The metasurface has a high reflectance of 0.94 and achieves a phase coverage of 320between 9.8 GHz and 11 GHz.Then,by encoding the phase distribution of the meta-atoms,various OAM vortex beams including 1,2,3,and 4 orders are generated,where the purity of all modes can be above 70%.Moreover,the metasurface can also deflect the OAM beam with a certain angle while maintaining high purity,which can be applied to reduce the influence of the alignment deviation between transmitting and receiving antennas during the communication processes.As a validation,the metasurface composed of 30×30 meta-atoms is fabricated and measured.Both simulation and measurement results demonstrate the capability of the proposed metasurface to generate reconfigurable OAM beams with high purity,indicating the application potentials of proposed meta-devices in future OAM communications.展开更多
Continuous pulse wave signals monitoring is the essential basis for clinical cardiovascular diagnosis and treatment.Recent researches show the majority of current electronic pulse sensors usually face challenges in el...Continuous pulse wave signals monitoring is the essential basis for clinical cardiovascular diagnosis and treatment.Recent researches show the majority of current electronic pulse sensors usually face challenges in electrical safety concern,poor durability and demanding precision in position alignment.Thus,a highly sensitive,inherently electrical safe,robust and alignment-free device is highly desired.Here,we present a wearable alignment-free microfber-based sensor chip(AFMSC)for precise vital signs monitoring and cardiovascular health assessment.The AFMSC comprises an optical micro/nano fber sensor(MNF)and a fexible soft liquid sac while the MNF sensor is used to perceive the physiological signals and the liquid sac is used to eliminate the misalignment.The real-time and accurate monitoring of the pulse signals was realized by tracking the optical power variation of transmitted light from MNF.Then,the cardiovascular vital signs extracted from radial artery pulse signals were used to evaluate cardiovascular health condition and the results were in accordance with human physiological characteristics.Moreover,the pulse signals from diferent arterial area,the respiration signals from chest and the radial pulse signals before and after exercise were detected and analyzed.The non-invasive,continuous and accurate monitoring of cardiovascular health based on the reported wearable and alignment-free device is promising in both ftness monitoring and medical diagnostics for cardiovascular disease prevention and diagnosis.展开更多
Reservoir computing is a potential neuromorphic paradigm for promoting future disruptive applications in the era of the Internet of Things,owing to its well-known low training cost and compatibility with hardware.It h...Reservoir computing is a potential neuromorphic paradigm for promoting future disruptive applications in the era of the Internet of Things,owing to its well-known low training cost and compatibility with hardware.It has been successfully implemented by injecting an input signal into a spatially extended reservoir of nonlinear nodes or a temporally extended reservoir of a delayed feedback system to perform temporal information processing.Here we propose a novel nondelay-based reservoir computer using only a single micromechanical resonator with hybrid nonlinear dynamics that removes the usually required delayed feedback loop.The hybrid nonlinear dynamics of the resonator comprise a transient nonlinear response,and a Duffing nonlinear response is first used for reservoir computing.Due to the richness of this nonlinearity,the usually required delayed feedback loop can be omitted.To further simplify and improve the efficiency of reservoir computing,a self-masking process is utilized in our novel reservoir computer.Specifically,we numerically and experimentally demonstrate its excellent performance,and our system achieves a high recognition accuracy of 93%on a handwritten digit recognition benchmark and a normalized mean square error of 0.051 in a nonlinear autoregressive moving average task,which reveals its memory capacity.Furthermore,it also achieves 97.17±1%accuracy on an actual human motion gesture classification task constructed from a six-axis IMU sensor.These remarkable results verify the feasibility of our system and open up a new pathway for the hardware implementation of reservoir computing.展开更多
Fluorinated porous organic networks(F-PONs)have demonstrated unique properties and applications,but approaches capable of affording F-PONs with high fluorine content and robust nanoporous architecture under metal-free...Fluorinated porous organic networks(F-PONs)have demonstrated unique properties and applications,but approaches capable of affording F-PONs with high fluorine content and robust nanoporous architecture under metal-free and easy handling conditions are still rarely reported.Herein,using polydivinylbenzene(PDVB)as an easily available precursor,a novel and straightforward approach was developed to afford F-PONs via a dehydrative Friedel-Crafts reaction using perfluorinated benzylic alcohols as the cross-linking agent promoted by Bronsted acid(trifluoromethanesulfonic acid).The afforded material(F-PDVB)featured high fluorine content(22 at.%),large surface area(771 m^(2)·g^(-1)),and good chemical/thermal stability,rendering them as promising candidates for the adsorption of CO_(2),hydrocarbons,fluorocarbons,and chlorofluorocarbons,with weight capacities up to 520 wt.%being achieved.This simple methodology can be extended to fabricate fluorinated hyper-crosslinked polymers(F-HCPs)from rigid aromatic monomers.The progress made in this work will open new opportunities to further expand the involvement of fluorinated materials in large scale applications.展开更多
Background::Non-transport unintentional injuries(NTUIs)are major public concerns,especially among children and adolescents in low-and middle-income countries.With environmental and cognitive changes,a recent systemati...Background::Non-transport unintentional injuries(NTUIs)are major public concerns,especially among children and adolescents in low-and middle-income countries.With environmental and cognitive changes,a recent systematic description of global trends and regional differences concerning NTUIs is urgently needed for the global agenda of relevant policy-making and intervention target findings.Methods::We used mortality,population,and socio-demographic-index(SDI)data from Global Burden of Disease 2019 to analyze the trends of NTUIs mortality.We applied the slope index of inequality(SII)and relative index of inequality(RII)to measure the absolute and relative inequality between countries and territories.The concentration curve and concentration index(CI)were also used to measure the inequality.We conducted a sensitivity analysis to make our findings credible.Results::In 2019,there were 205,000 deaths due to NTUIs among children and adolescents aged 5 to 24 years,which decreased from 375,000 in 1990.In 2019,the age-standardized mortality rate(ASMR)was 8.13 per 100,000,ranging from the lowest in the Netherlands(0.90 per 100,000)to the highest in the Solomon Islands(29.34 per 100,000).The low-middle SDI group had the highest ASMR of NTUIs,while the low SDI group had the slowest decrease.After excluding the death caused by"exposure to forces of nature"and"other unintentional injuries",drowning accounted for the most deaths in almost every SDI group,gender,and age group,but the major causes of death varied in different subgroups.For example,animal contact was a major cause in low and low-middle SDI groups but less in high SDI groups,while high and high-middle SDI groups had a higher proportion of deaths for foreign body and poisonings.The SII showed a declining trend,but the RII and CI did not,which might indicate that inequality was persistent.Similar results were found in the sensitivity analysis.Conclusions::Despite the declining trend of the mortality rate and the narrowing gap between countries,there were still a large number of children and adolescents dying from NTUIs,and those experiencing social-economic disadvantages remained at high mortality.Embedding the prevention of NTUIs into sustainable development goals might contribute to the progress of reducing death and inequalities,which ensures that no one is left behind.展开更多
基金Liuzhou City's Top Ten Hundred Talents Project,Liuzhou Science and Technology Project(Grant Nos.2021CBC0126 and 2021CBC0123)Guangxi Zhuang Autonomous Region Health and Family Planning Commission Projects(Z20210561,Z20210903)+1 种基金liuzhou Scienceand Technology Plan Projects(2021CBC0121,2021CBC0128).
文摘Glycogen metabolism plays a key role in the development of hepatoellular carcinoma(HCC),but the function of glycogen metabolism genes in the tumor microenvironment(TME)is still to be elucidated.Single cell RNA-seq data were obtained from ten HCC tumor samples totaling 64,545 cells and 65 glycogen metabolism genes were analyzed bya nonnegative matrix factorization(NMF).The prognosis and immune response of new glycogen TME cell dusters were predicted by using HCC and immunotherapy cohorts from public databases.HOC single cell analysis was divided into fibroblasts,NT T cells,macrophages,endothelial clls,and B cells,which were separately divided into new cell clusters by glycogen metabolism gene annotation.Pseudo temporal trajectory analysis demonstrated the temporal differentiation trajectory of different glycogen subtype cell dusters.Cellular communication analysis revealed extensive interactions between endothelial cells with glycogen metabolizing TME cell.related subtypes and diferent glycogen subtype cell clusters.SCENIC analysis of transcription factors upstream of TME cell clusters with different glycogen metabolism.In addition,TME cell dusters of glycogen metabolism were found to be enriched in expression in CAF subtypes,CD8 depleted,M1,and M2 types.Bulk seq analysis showed the prognostic signifcance of glycogen metabolism.mediated TME cell dusters in HCC,while a significant immune response was found in the immunotherapy cohort in patients treated with immune checkpoint blockade(ICB),especially for CAFs,T cells,and macrophages In summary,our study reveals for the first time that glycogen metabolism mediates intercellular communication in the hepatocellular carcinoma microenvironment while elucidating the anti-tumor mechanisms and immune prognostic responses of different subtypes of cell dusters.
基金support from the National Natural Science Foundation of China(61975046)。
文摘Transparent microwave absorbers that exhibit high optical transmittance and microwave absorption capability are ideal,although having a fixed absorption performance limits their applicability.Here,a simple,transparent,and thermally tunable microwave absorber is proposed,based on a patterned vanadium dioxide(VO_(2))film.Numerical calculations and experiments demonstrate that the proposed VO_(2)absorber has a high optical transmittance of 84.9%at 620 nm;its reflection loss at 15.06 GHz can be thermally tuned from–4.257 to–60.179 dB,and near-unity absorption is achieved at 523.750 K.Adjusting only the patterned VO_(2)film duty cycle can change the temperature of near-unity absorption.Our VO_(2)absorber has a simple composition,a high optical transmittance,a thermally tunable microwave absorption performance,a large modulation depth,and an adjustable temperature tuning range,making it promising for application in tunable sensors,thermal emitters,modulators,thermal imaging,bolometers,and photovoltaic devices.
基金supported by the Science and Technology Development Fund from Macao SAR(FDCT-0057/2019/A1,0092/2019/A2,and 0035/2019/AMJ)Startup grants(SRG2018-00140-IAPME)from the Research and Development Office at University of Macao+1 种基金National Natural Science Foundation of China(Grant no.21875040 and 21905051)Chongqing Key Laboratory fund of Soft-Matter Material Chemistry and Function Manufacturing(No.20200003).
文摘Separators or electrolyte membranes are recognized as the key components to guarantee ion transport in rechargeable batteries.However,the ever-growing applications of the battery systems for diverse working environments bring new challenges,which require advanced battery membranes with high thermal stability,excellent mechanical strength,high voltage tolerance,etc.Therefore,it is highly desirable to design novel methods/concepts to solve the current challenges for battery membranes through understanding the mechanism of novel phenomena and electrochemical reactions in battery systems working under unconventional conditions.Recently,the new emerging Janus separators or electrolyte membranes with two or more distinct chemical/physical properties arising from their asymmetric structure and composition,are promising to address the above challenges via rational design of their targeted functionalities.To this end,in this review,we first briefly cover the current challenges of the traditional battery membrane for battery devices working in unconventional conditions.Then,the state-of-art developments of the rational design of Janus membranes to overcome the above challenges for diverse battery applications are summarized.Finally,we outline these latest developments,challenges,and future potential directions of the Janus membrane.Our review is aimed to provide basic guidance for developing functional separators or electrolyte membranes for advanced batteries.
基金Supported by Hebei Province Phase III Modern Agricultural Industry Technology System Cow Innovation Team Building ProjectThe Fourth Batch of High-end Talent Project in Hebei ProvinceHebei Provincial Science and Technology Innovation Leading Talents(21130243A).
文摘[Objectives]This study was conducted to investigate the main factors affecting the aerobial plate count in raw milk.[Methods]Drinking water,medicated baths and raw milk under different storage and transportation conditions were detected for the values of aerobial plate count to analyze their effects on the aerobial plate count in raw milk.[Results]Disinfection of drinking water tanks could significantly reduce the aerobial plate count in water.The use of medicated baths before and after milking could effectively reduce the aerobial plate count and had a significant bactericidal effect.The growth of microorganisms in raw milk stored below 4℃was relatively slow.Regularly disinfecting drinking water tanks and disinfecting nipples before and after milking could reduce the aerobial plate count in the tanks and nipples.After raw milk was extruded,the temperature should decrease to 0-4℃within 2 h,and the storage time should not exceed 48 h,which could effectively control the aerobial plate count in raw milk.[Conclusions]This study provides a reference for scientific control of the aerobial plate count in raw milk.
基金Project supported by the National Natural Science Foundation of China (No. 11972204)。
文摘In this article, the nonlinear dynamic responses of sandwich functionally graded(FG) porous cylindrical shell embedded in elastic media are investigated. The shell studied here consists of three layers, of which the outer and inner skins are made of solid metal, while the core is FG porous metal foam. Partial differential equations are derived by utilizing the improved Donnell's nonlinear shell theory and Hamilton's principle. Afterwards, the Galerkin method is used to transform the governing equations into nonlinear ordinary differential equations, and an approximate analytical solution is obtained by using the multiple scales method. The effects of various system parameters,specifically, the radial load, core thickness, foam type, foam coefficient, structure damping,and Winkler-Pasternak foundation parameters on nonlinear internal resonance of the sandwich FG porous thin shells are evaluated.
基金Project supported by the National Natural Science Foundation of China(No.11672071)the Fundamental Research Funds for the Central Universities(No.N170504023)
文摘The nonlinear vibration characteristics of the piezoelectric circular cylindrical nanoshells resting on an elastic foundation are analyzed. The small scale effect and thermo-electro-mechanical loading are taken into account. Based on the nonlocal elasticity theory and Donnell's nonlinear shell theory, the nonlinear governing equations and the corresponding boundary conditions are derived by employing Hamilton's principle. Then,the Galerkin method is used to transform the governing equations into a set of ordinary differential equations, and subsequently, the multiple-scale method is used to obtain an approximate analytical solution. Finally, an extensive parametric study is conducted to examine the effects of the nonlocal parameter, the external electric potential, the temperature rise, and the Winkler-Pasternak foundation parameters on the nonlinear vibration characteristics of circular cylindrical piezoelectric nanoshells.
文摘The Particle Velocity Sensor (PVS) is a kind of acoustic transducer which measures the particle velocity directly with figure-of-eight directivity. This paper proposes a near-field noise scanning technology based on the research of PVS, pressure-particle velocity (P-U) probe, and its application in noise source identification. Firstly, the principle and characteristics of PVS are presented. Secondly, a P-U probe is designed on the basis of PVS development. Finally, the noise measurement experiment for a single source is arranged and conducted. The result shows that the proposed P-U probe performs well in near-field noise source identification and localization.
基金supported by the National Natural Science Foundation of China(No.11972204)。
文摘Composite cylindrical shells,as key components,are widely employed in large rotating machines.However,due to the frequency bifurcations and dense frequency spectra caused by rotation,the nonlinear vibration usually has the behavior of complex multiple internal resonances.In addition,the varying temperature fields make the responses of the system further difficult to obtain.Therefore,the multiple internal resonances of composite cylindrical shells with porosities induced by rotation with varying temperature fields are studied in this paper.Three different types of the temperature fields,the Coriolis forces,and the centrifugal force are considered here.The Hamilton principle and the modified Donnell nonlinear shell theory are used to obtain the equilibrium equations of the system,which are transformed into the ordinary differential equations(ODEs)by the multi-mode Galerkin technique.Thereafter,the pseudo-arclength continuation method,which can identify the regions of instability,is introduced to obtain the numerical results.The detailed parametric analysis of the rotating composite shells is performed.Multiple internal resonances caused by the interaction between backward and forward wave modes and the energy transfer phenomenon are detected.Besides,the nonlinear amplitude-frequency response curves are different under different temperature fields.
基金This work was supported by Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘A series of uniform single-phase spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors were prepared via a microwave hydrothermal method by using trisodium citrate dehydrate as surfactant.The phase structure,morphology and photoluminescence properties were measured by powder X-ray diffraction,scanning electron microscope and fluorescence spectrometer,respectively.The results show that uniform spherical microcrystals with diameters in the range of 2–4μm are obtained.And the phase and morphology of samples are not significantly changed by doping rare earth(RE^(3+))ions.Under the excitation wavelength of 356 and 365 nm,the samples BaWO 4:0.03Dy^(3+),yTm^(3+)can emit cold white light.In order to lower the correlated color temperature(CCT)to get a warm white light,the Eu^(3+)ions were doped into BaWO 4:0.03Dy^(3+),0.01Tm^(3+).Especially,under the excitation of 365 nm,BaWO 4:0.03Dy^(3+),0.01Tm^(3+),0.03Eu^(3+)phosphor shew a bright warm white light with color coordi-nate of(0.4013,0.3629)and CCT of 3288 K.Moreover,in the BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors,the energy transfer mechanism among Dy^(3+),Tm^(3+)and Eu^(3+)ions have been discussed and the change of electron structures have been calculated by first-principles calculations.The results shew that the uniform single-phase spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors could be favorable candidates in warm white LEDs.
基金supported by the National Natural Science Foundation of China(No.12202229)the Science Center for Gas Turbine Project,China(No.P2022-B-III-002-001)the Scientific Research Projects of Tianjin Education Commission,China(Nos.2020KJ018,2020KJ060).
文摘Maneuvering flight substantially affects the dynamic behavior of rotors;particularly,such flight may cause rubbing between a rotor and stator,which is one of the most serious damages in aircraft engines.In this paper,a nonlinear dynamic model for describing the dynamic characteristics of a rub-impact rotor system during maneuvering flight is established based on the Lagrange equations.Subsequently,numerical simulations employing the Newmark method are performed,delving into the detailed discussion of the influence of parameters such as rotational speed and maneuvering flight on the transient and steady-state responses of the rotor system.The effect mechanism of maneuver load and its coupling with rub impact is revealed.The results show that the impact response induced by maneuvering flight is more obvious in the subcritical state than in the supercritical state.The additional stiffness and damping are also induced;in particular,the additional damping has a coupling effect.Moreover,the rub impact imposes an additional constraint on the rotor system,thereby weakening the influence of the maneuver load and becoming the major factor that determines the dynamic behavior of the rotor system at high speeds.
基金by the China Medical Board(Grant#21-434 to YS)Capital’s Funds for Health Improvement and Research(2022-1G-4251 to YS).
文摘Summary What is already known about this topic?Myopia has been identified as a significant emerging challenge and policy priority among children and adolescents in China by the Ministry of Education and seven other departments.Limited research has been conducted to investigate the collective impact of outdoor time and other modifiable factors on the incidence of myopia.
基金supports from National Natural Science Foundation of China(No.11972204)Natural Science Foundation of Tianjin,China(No.19JCQNJC02500)。
文摘Magnetorheological(MR)dampers show superior performance in reducing rotor vibration,but their high nonlinearity will cause nonsynchronous response,resulting in fatigue and instability of rotors.Herein,we are devoted to the investigation of the nonlinear characteristics of MR damper mounted on a flexible rotor.First,Reynolds equations with bilinear constitutive equations of MR fluid are employed to derive nonlinear oil film forces.Then,the Finite Element(FE)model of rotor system is developed,where the local nonlinear support forces produced by MR damper and its coupling effects with the rotor are considered.A hybrid numerical method is proposed to solve the nonlinear FE motion equations of the MR damper-rotor system.To validate the proposed model,a rotor test bench with two dual-coil MR dampers is constructed,upon which experimental studies on the dynamic characteristics of MR damper-rotor system are carried out.The effects of different system parameters,including rotational speed,excitation current and amount of unbalance,on nonlinear dynamic behaviors of MR damper-rotor system are evaluated.The results show that the system may appear chaos,jumping,and other complex nonlinear phenomena,and the level of the nonlinearity can be effectively alleviated by applying suitable excitation current and oil supply pressure.
基金supported by the National Natural Science Foundation of China(NSFC)under grant No.51902155the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘Revealing the epitaxial growth mechanism and the interfacial coupling effect between oxide films will help to build a“structure-property”bridge for the design of microelectronic devices.Here,the epitaxial growth mechanism and the interfacial coupling in Bi_(0.5)Na_(0.5)TiO_(3)/SrTiO_(3)(BNT/STO)heterointerfaces are investigated by the aberration-corrected scanning transmission electron microscopy,which is synthesized by a hydrothermal method.The results illustrate that 4 mol/L NaOH leads to not only the epitaxial growth of the BNT film but also the mutual diffusion of elements.The uneven distribution of local elements in BNT films is observed and confirmed to impact the cation displacements of B-site and lattice distortion.However,the overall trend of B-site cation displacement at the BNT/STO heterointerfaces is dominated by the interfacial strain.Additionally,the oxygen octahedral tilt exhibits continuous tilt patterns of a^(0)a^(0)a^(0)-a−b^(0)c−-a^(0)a^(0)c−-a^(0)b−c−-a−b−c−from the substrate to BNT film due to the constraint of the substrate and presents a strong correlation with cation displacement.These results are helpful to understand the underlying atomic structures and physical properties of BNT epitaxial thin films.
基金supported by the Special Funds for Creative Research(Grant No.2022C61540)the National Natural Science Foundation of China(NSFC,Grant Nos.61972012 and 61732016).
文摘Intrinsic image decomposition is an important and long-standing computer vision problem.Given an input image,recovering the physical scene properties is ill-posed.Several physically motivated priors have been used to restrict the solution space of the optimization problem for intrinsic image decomposition.This work takes advantage of deep learning,and shows that it can solve this challenging computer vision problem with high efficiency.The focus lies in the feature encoding phase to extract discriminative features for different intrinsic layers from an input image.To achieve this goal,we explore the distinctive characteristics of different intrinsic components in the high-dimensional feature embedding space.We define feature distribution divergence to efficiently separate the feature vectors of different intrinsic components.The feature distributions are also constrained to fit the real ones through a feature distribution consistency.In addition,a data refinement approach is provided to remove data inconsistency from the Sintel dataset,making it more suitable for intrinsic image decomposition.Our method is also extended to intrinsic video decomposition based on pixel-wise correspondences between adjacent frames.Experimental results indicate that our proposed network structure can outperform the existing state-of-the-art.
基金supported by the National Natural Science Foundation of China(62171165)。
文摘In this paper,we proposed an active metasurface in reflection manner that can generate reconfigurable OAM vortex beams with high purity in the X-band.The metasurface has a high reflectance of 0.94 and achieves a phase coverage of 320between 9.8 GHz and 11 GHz.Then,by encoding the phase distribution of the meta-atoms,various OAM vortex beams including 1,2,3,and 4 orders are generated,where the purity of all modes can be above 70%.Moreover,the metasurface can also deflect the OAM beam with a certain angle while maintaining high purity,which can be applied to reduce the influence of the alignment deviation between transmitting and receiving antennas during the communication processes.As a validation,the metasurface composed of 30×30 meta-atoms is fabricated and measured.Both simulation and measurement results demonstrate the capability of the proposed metasurface to generate reconfigurable OAM beams with high purity,indicating the application potentials of proposed meta-devices in future OAM communications.
基金This work was supported by the National Science Fund of China for Excellent Young Scholars(No.61922033)the Science Found for Creative Research Groups of the Natural Science Foundation of Hubei(No.2018CFA004)the Innovation Fund of WNLO.
文摘Continuous pulse wave signals monitoring is the essential basis for clinical cardiovascular diagnosis and treatment.Recent researches show the majority of current electronic pulse sensors usually face challenges in electrical safety concern,poor durability and demanding precision in position alignment.Thus,a highly sensitive,inherently electrical safe,robust and alignment-free device is highly desired.Here,we present a wearable alignment-free microfber-based sensor chip(AFMSC)for precise vital signs monitoring and cardiovascular health assessment.The AFMSC comprises an optical micro/nano fber sensor(MNF)and a fexible soft liquid sac while the MNF sensor is used to perceive the physiological signals and the liquid sac is used to eliminate the misalignment.The real-time and accurate monitoring of the pulse signals was realized by tracking the optical power variation of transmitted light from MNF.Then,the cardiovascular vital signs extracted from radial artery pulse signals were used to evaluate cardiovascular health condition and the results were in accordance with human physiological characteristics.Moreover,the pulse signals from diferent arterial area,the respiration signals from chest and the radial pulse signals before and after exercise were detected and analyzed.The non-invasive,continuous and accurate monitoring of cardiovascular health based on the reported wearable and alignment-free device is promising in both ftness monitoring and medical diagnostics for cardiovascular disease prevention and diagnosis.
基金the National Key Research and Development Program of China(Grant No.2018YFB2002300)the National Natural Science Foundation of China(Grant No.61971399)the Key Research Program of Frontier Science(CAS,Grant No.ZDBS-LY-JSC028).
文摘Reservoir computing is a potential neuromorphic paradigm for promoting future disruptive applications in the era of the Internet of Things,owing to its well-known low training cost and compatibility with hardware.It has been successfully implemented by injecting an input signal into a spatially extended reservoir of nonlinear nodes or a temporally extended reservoir of a delayed feedback system to perform temporal information processing.Here we propose a novel nondelay-based reservoir computer using only a single micromechanical resonator with hybrid nonlinear dynamics that removes the usually required delayed feedback loop.The hybrid nonlinear dynamics of the resonator comprise a transient nonlinear response,and a Duffing nonlinear response is first used for reservoir computing.Due to the richness of this nonlinearity,the usually required delayed feedback loop can be omitted.To further simplify and improve the efficiency of reservoir computing,a self-masking process is utilized in our novel reservoir computer.Specifically,we numerically and experimentally demonstrate its excellent performance,and our system achieves a high recognition accuracy of 93%on a handwritten digit recognition benchmark and a normalized mean square error of 0.051 in a nonlinear autoregressive moving average task,which reveals its memory capacity.Furthermore,it also achieves 97.17±1%accuracy on an actual human motion gesture classification task constructed from a six-axis IMU sensor.These remarkable results verify the feasibility of our system and open up a new pathway for the hardware implementation of reservoir computing.
基金supported financially by the Division of Chemical Sciences,Geosciences,and Biosciences,Office of Basic Energy Sciences,US Department of Energy.
文摘Fluorinated porous organic networks(F-PONs)have demonstrated unique properties and applications,but approaches capable of affording F-PONs with high fluorine content and robust nanoporous architecture under metal-free and easy handling conditions are still rarely reported.Herein,using polydivinylbenzene(PDVB)as an easily available precursor,a novel and straightforward approach was developed to afford F-PONs via a dehydrative Friedel-Crafts reaction using perfluorinated benzylic alcohols as the cross-linking agent promoted by Bronsted acid(trifluoromethanesulfonic acid).The afforded material(F-PDVB)featured high fluorine content(22 at.%),large surface area(771 m^(2)·g^(-1)),and good chemical/thermal stability,rendering them as promising candidates for the adsorption of CO_(2),hydrocarbons,fluorocarbons,and chlorofluorocarbons,with weight capacities up to 520 wt.%being achieved.This simple methodology can be extended to fabricate fluorinated hyper-crosslinked polymers(F-HCPs)from rigid aromatic monomers.The progress made in this work will open new opportunities to further expand the involvement of fluorinated materials in large scale applications.
基金This study was supported by grants from the National Statistical ScientificResearch Program(No.2021LY052)the China Medical Board(21-434 to YS)the National Natural Science Foundation of China(No.82073573).
文摘Background::Non-transport unintentional injuries(NTUIs)are major public concerns,especially among children and adolescents in low-and middle-income countries.With environmental and cognitive changes,a recent systematic description of global trends and regional differences concerning NTUIs is urgently needed for the global agenda of relevant policy-making and intervention target findings.Methods::We used mortality,population,and socio-demographic-index(SDI)data from Global Burden of Disease 2019 to analyze the trends of NTUIs mortality.We applied the slope index of inequality(SII)and relative index of inequality(RII)to measure the absolute and relative inequality between countries and territories.The concentration curve and concentration index(CI)were also used to measure the inequality.We conducted a sensitivity analysis to make our findings credible.Results::In 2019,there were 205,000 deaths due to NTUIs among children and adolescents aged 5 to 24 years,which decreased from 375,000 in 1990.In 2019,the age-standardized mortality rate(ASMR)was 8.13 per 100,000,ranging from the lowest in the Netherlands(0.90 per 100,000)to the highest in the Solomon Islands(29.34 per 100,000).The low-middle SDI group had the highest ASMR of NTUIs,while the low SDI group had the slowest decrease.After excluding the death caused by"exposure to forces of nature"and"other unintentional injuries",drowning accounted for the most deaths in almost every SDI group,gender,and age group,but the major causes of death varied in different subgroups.For example,animal contact was a major cause in low and low-middle SDI groups but less in high SDI groups,while high and high-middle SDI groups had a higher proportion of deaths for foreign body and poisonings.The SII showed a declining trend,but the RII and CI did not,which might indicate that inequality was persistent.Similar results were found in the sensitivity analysis.Conclusions::Despite the declining trend of the mortality rate and the narrowing gap between countries,there were still a large number of children and adolescents dying from NTUIs,and those experiencing social-economic disadvantages remained at high mortality.Embedding the prevention of NTUIs into sustainable development goals might contribute to the progress of reducing death and inequalities,which ensures that no one is left behind.