Objective This study aimed to explore the association between body mass index(BMI)and mortality based on the 10-year population-based multicenter prospective study.Methods A general population-based multicenter prospe...Objective This study aimed to explore the association between body mass index(BMI)and mortality based on the 10-year population-based multicenter prospective study.Methods A general population-based multicenter prospective study was conducted at four sites in rural China between 2013 and 2023.Multivariate Cox proportional hazards models and restricted cubic spline analyses were used to assess the association between BMI and mortality.Stratified analyses were performed based on the individual characteristics of the participants.Results Overall,19,107 participants with a sum of 163,095 person-years were included and 1,910 participants died.The underweight(<18.5 kg/m^(2))presented an increase in all-cause mortality(adjusted hazards ratio[aHR]=2.00,95%confidence interval[CI]:1.66–2.41),while overweight(≥24.0 to<28.0 kg/m^(2))and obesity(≥28.0 kg/m^(2))presented a decrease with an aHR of 0.61(95%CI:0.52–0.73)and 0.51(95%CI:0.37–0.70),respectively.Overweight(aHR=0.76,95%CI:0.67–0.86)and mild obesity(aHR=0.72,95%CI:0.59–0.87)had a positive impact on mortality in people older than 60 years.All-2 cause mortality decreased rapidly until reaching a BMI of 25.7 kg/m(aHR=0.95,95%CI:0.92–0.98)and increased slightly above that value,indicating a U-shaped association.The beneficial impact of being overweight on mortality was robust in most subgroups and sensitivity analyses.Conclusion This study provides additional evidence that overweight and mild obesity may be inversely related to the risk of death in individuals older than 60 years.Therefore,it is essential to consider age differences when formulating health and weight management strategies.展开更多
Background: Resistance exercise leads to improved muscle function and metabolic homeostasis.Yet how circadian rhythm impacts exercise outcomes and its molecular transduction remains elusive.Methods: Human volunteers w...Background: Resistance exercise leads to improved muscle function and metabolic homeostasis.Yet how circadian rhythm impacts exercise outcomes and its molecular transduction remains elusive.Methods: Human volunteers were subjected to 4 weeks of resistance training protocols at different times of day to assess training outcomes and their associations with myokine irisin.Based on rhythmicity of Fibronectin type III domain containing 5(FNDC5/irisin),we trained wild type and FNDC5 knockout mice at late active phase(high FNDC5/irisin level)or late rest phase(low FNDC5/irisin level)to analyze exercise benefits on muscle function and metabolic homeostasis.Molecular analysis was performed to understand the regulatory mechanisms of FNDC5 rhythmicity and downstream signaling transduction in skeletal muscle.Results: In this study,we showed that regular resistance exercises performed at different times of day resulted in distinct training outcomes in humans,including exercise benefits and altered plasma metabolomics.We found that muscle FNDC5/irisin levels exhibit rhythmicity.Consistent with human data,compared to late rest phase(low irisin level),mice trained chronically at late active phase(high irisin level)gained more muscle capacity along with improved metabolic fitness and metabolomics/lipidomics profiles under a high-fat diet,whereas these differences were lost in FNDC5 knockout mice.Mechanistically,Basic helix-loop-helix ARNT like 1(BMAL1)and Peroxisome proliferative activated receptor,gamma,coactivator 1 alpha 4(PGC1α4)induce FNDC5/irisin transcription and rhythmicity,and the signaling is transduced viaαV integrin in muscle.Conclusion: Together,our results offered novel insights that exercise performed at distinct times of day determines training outcomes and metabolic benefits through the rhythmic regulation of the BMAL1/PGC1α4-FNDC5/irisin axis.展开更多
Lithium metal batteries face serious safety challenges caused by flammable organic electrolytes and the growth of lithium dendrite.Trimethyl phosphate(TMP)is a promising alternative for flammable carbonate electrolyte...Lithium metal batteries face serious safety challenges caused by flammable organic electrolytes and the growth of lithium dendrite.Trimethyl phosphate(TMP)is a promising alternative for flammable carbonate electrolyte solvents owing to its nonflammable nature.But the low-concentration TMP-based electrolyte is unstable with the lithium metal anode.Here,a TMP-contained quasisolid electrolyte(PIQSE)with porous polyimide(PI)as supporting skeleton is designed.The cross-linking structure generated by UV curing in PIQSE can lock the reactive TMP solvent to reduce its contact with Li metal.Besides,the PI supporting skeleton with high-temperature resistance can significantly enhance the thermal stability of PIQSE.The combination of PI and TMP prompts the high ionic conductivity and excellent nonflammability of PIQSE.The LiFePO_(4)/Li cell using PIQSE shows superior electrochemical performance in a wide temperature range from-10 to 60°C.Furthermore,the cells with highvoltage cathode of LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)were matched with PIQSE exhibit good cyclic and rate performance.The NCM622/PIQSE/Li pouch cell was also fabricated.It exhibits a high discharge capacity of 182.9mAh.g^(-1),and can stably light up LEDs after folding and shearing tests,demonstrating broad prospects for highly safe energy storage applications.展开更多
Owing to uncontrolled and uneven electrodeposition and side reactions,Zn metal anodes inevitably suffer from issues such as dendrite growth,hydrogen evolution reactions,and surface passivation.This paper proposes an e...Owing to uncontrolled and uneven electrodeposition and side reactions,Zn metal anodes inevitably suffer from issues such as dendrite growth,hydrogen evolution reactions,and surface passivation.This paper proposes an efficient strategy to address these critical issues for realizing long-life and high-capacity aqueous zinc-ion hybrid supercapacitors(ZHSCs)by incorporating low-concentration(0.05 mol·L^(-1))redox RbI electrolyte additives.Specifically,rubidium cations have the ability to influence the negative Zn electrode surface via an electrostatic shielding mechanism,effectively protecting the electrode and minimizing undesired side reactions.In an aqueous solution,iodide anions actively solvate Zn^(2+)ions by stabilizing and modulating the solvation shell surrounding Zn^(2+).Moreover,the presence of iodide ions promotes the uniform deposition of Zn^(2+)species by selective adsorption onto the electrode surface.The synergistic effect of the electrostatic shielding and halogen ions enables the realization of aqueous symmetric Zn||Zn cells with a substantial cycle life of more than 2000 h Additionally,when applied to commercial activated carbon(AC),the proposed strategy facilitates the development of aqueous ZHSCs,exhibiting high specific capacitances(148.8 F·g^(-1)at 4 A·g^(-1))and ultra-long cycling stability.展开更多
A theoretical model is developed to investigate the sliding electrical contact behavior with the consideration of the electrical-thermal–mechanical coupling effect.The interfacial electrical resistance and electrical...A theoretical model is developed to investigate the sliding electrical contact behavior with the consideration of the electrical-thermal–mechanical coupling effect.The interfacial electrical resistance and electrical constriction resistance are both involved.The Joule heating due to electrical contact resistance and the frictional energy dissipation are considered in the model for the assessment of the temperature rise at the contact interface.A singular integral equation for sliding electrical contact considering both frictional and Joule heat is developed and solved to obtain the contact pressure,current density,and temperature rise.Furthermore,a discrete fast Fourier transform-based boundary element method is applied to obtain the numerical solution of sliding electrical contact.Good agreement is achieved between theoretical and numerical results.After the validation,the effects of potential drop and sliding velocity on sliding electrical contact behavior are investigated.The results indicate that the proposed theoretical model can provide an exact prediction of multi-physics sliding electrical contact behavior.展开更多
Object contour plays an important role in fields such as semantic segmentation and image classification. However, the extraction of contour is a difficult task, especially when the contour is incomplete or unclosed. I...Object contour plays an important role in fields such as semantic segmentation and image classification. However, the extraction of contour is a difficult task, especially when the contour is incomplete or unclosed. In this paper, the existing contour detection approaches are reviewed and roughly divided into three categories： pixel-based, edge-based, and region-based. In addition, since the traditional contour detection approaches have achieved a high degree of sophistication, the deep convolutional neural networks （DCNNs） have good performance in image recognition, therefore, the DCNNs based contour detection approaches are also covered in this paper. Moreover, the future development of contour detection is analyzed and predicted.展开更多
Lithium （Li） metal has been considered as the most attractive anode materials for Li-ion batteries （LIBs） due to its high theoretic specific capacity. The formation of unstable solid electrolyte interphase （SEI）...Lithium （Li） metal has been considered as the most attractive anode materials for Li-ion batteries （LIBs） due to its high theoretic specific capacity. The formation of unstable solid electrolyte interphase （SEI） and dendritic Li on the metal anode, however, hindered its practical application. Herein, to address the issues, a Li-free electrode with ultrathin Al2O3 coated on reduced graphene oxide （rGO） membrane that covers a Cu foil current collector was developed. The composite electrode exhibits excellent interfacial protection of lithium metal deposited between Cu foil and rGO electrochemically. Firstly, it affords good Li^＋ permeability from the electrolyte. Secondly, the ultrathin Al2O3 has sufficient mechanical strength to inhibit the penetration of Li dendrite. Li metal was observed uniformly deposited between rGO membrane and Cu collector, and stable cycle performance of Li plating/stripping with Coulombic efficiency of ~ 91.75% at the lOOth cycle is achieved in organic carbonate electrolyte without any additives.展开更多
Most gear fault diagnosis(GFD)approaches su er from ine ciency when facing with multiple varying working conditions at the same time.In this paper,a non-negative matrix factorization(NMF)-theoretic co-clustering strat...Most gear fault diagnosis(GFD)approaches su er from ine ciency when facing with multiple varying working conditions at the same time.In this paper,a non-negative matrix factorization(NMF)-theoretic co-clustering strategy is proposed specially to classify more than one task at the same time using the high dimension matrix,aiming to o er a fast multi-tasking solution.The short-time Fourier transform(STFT)is first used to obtain the time-frequency features from the gear vibration signal.Then,the optimal clustering numbers are estimated using the Bayesian information criterion(BIC)theory,which possesses the simultaneous assessment capability,compared with traditional validity indexes.Subsequently,the classical/modified NMF-based co-clustering methods are carried out to obtain the classification results in both row and column tasks.Finally,the parameters involved in BIC and NMF algorithms are determined using the gradient ascent(GA)strategy in order to achieve reliable diagnostic results.The Spectra Quest’s Drivetrain Dynamics Simulator gear data sets were analyzed to verify the e ectiveness of the proposed approach.展开更多
A new continuum damage mechanics model for fretting fatigue life prediction is established. In this model, the damage evolution rate is described by two kinds of quantities. One is associated with the cyclic stress ch...A new continuum damage mechanics model for fretting fatigue life prediction is established. In this model, the damage evolution rate is described by two kinds of quantities. One is associated with the cyclic stress characteristics obtained by the finite element （FE） analysis, and the other is associated with the material fatigue property identified from the fatigue test data of standard specimens. The wear is modeled by the energy wear law to simulate the contact geometry evolution. A two-dimensional （2D） plane strain FE implementation of the damage mechanics model and the energy wear model is presented in the platform of ABAQUS to simulate the evolutions of the fatigue damage and the wear scar. The effect of the specimen thickness is also investigated. The predicted results of the crack initiation site and the fretting fatigue life agree well with available experimental data. Comparisons are made with the critical plane Smith- Watson-Topper （SWT） method.展开更多
An approach based on continuum damage mechanics to fatigue life prediction for structures is proposed. A new fatigue damage evolution equation is developed, in which the pa- rameters are obtained in a simple way with ...An approach based on continuum damage mechanics to fatigue life prediction for structures is proposed. A new fatigue damage evolution equation is developed, in which the pa- rameters are obtained in a simple way with reference to the experimental results of fatigue tests on standard specimens. With the utilization of APDL language on the ANSYS platform, a finite element implementation is presented to perform coupling operation on damage evolution of mate- rial and stress redistribution. The fatigue lives of some notched specimens and a Pitch-change-link are predicted by using the above approach. The calculated results are validated with experimental data.展开更多
This work reported a facile approach to surface oxygen vacancy(O_(v))-enriched urchin-like TiO_(2) microparticles(U-TiO_(2)),which were highly effective and durable in catalyzing selective nitrate reduction to ammonia...This work reported a facile approach to surface oxygen vacancy(O_(v))-enriched urchin-like TiO_(2) microparticles(U-TiO_(2)),which were highly effective and durable in catalyzing selective nitrate reduction to ammonia(NOgRR),Specifically,the U-TiO_(2)delivered a mass activity of 1.15 min^(-1)mg^(-1)calyst.a low yield of toxic NO_(2)^(-)-N intermediate(≤0.4mg/L)and an exceptional high NH_(3)^(-)-N selectivity of 98.1%in treating 22.5 mg/L of NO_(3)^(-)-N under a potential of-0.60V vs.RHE,outperforming most of the reported oxidebased catalysts.When comparing the performance of U-TiO_(2)with that of the solid amorphous TiO_(2) counterpart(A-TiO_(2))that had close particle size but more O_(v) on surfaces,we identified that the O_(v) was the reactive sites,but rather than its content,the NO_(3)RR kinetics were primarily limited by the electron and mass transfer at U-TiO_(2)/water interfaces.Accordingly,the superior performance of U-TiO_(2)to A-TiO_(2)could be ascribed to the hierarchical urchin-like structure in U-TiO_(2).The in-situ DEMS test revealed that the NO_(3)RR on U-TiO_(2)followed a pathway of ^(*)NO_(3)^(-)→^(*)NO_(2)^(-)→^(*)NO→^(*)N→^(*)NH^(-)→^(*)NH_(2)→^(*)NH_(3).We also demonstrated that the U-TiO_(2) could keep its robust performance under a wide NO_(3)^(-)-N concentration range and in the presence of some co-existing ions(such as Ca^(2+),Cl^(-),Mg^(2+)).However,the presence of humic acid and CO_(3)^(2-) in water slowed down the NO_(3)RR on U-TiO_(2).This work provides a more fundamental insight into the O_(v)-driven NO_(3)RR process on TiO_(2),which should benefit for the development of eficient TiO_(2)-based catalvsts.展开更多
Safety issues induced by infinite anode volume change and uncontrolled lithium(Li)dendrite growth have become the biggest obstacle to the practical application of Li metal batteries.In addition,the tra-ditional rollin...Safety issues induced by infinite anode volume change and uncontrolled lithium(Li)dendrite growth have become the biggest obstacle to the practical application of Li metal batteries.In addition,the tra-ditional rolling method makes it difficult to manufacture thin Li foil with high mechanical strength and low Li content.Herein,a three-dimensional(3D)lithophilic carbon paper/copper(Cu)current collector hybrid anode with ultra-low Li metal content is prepared by a hot-pressing method.The highly re-versible and stable lithiophilic layer LiC_(x) formed in situ by heating/pressing treatment provides abun-dant nucleation sites and reduces the Li nucleation overpotential,thereby effectively suppressing Li den-drite growth.Moreover,the volume change and pulverization problems of Li metal anode during depo-sition/stripping also can be accommodated by the 3D skeleton.The optimization effect has been directly confirmed by in-situ optical and ex-situ scanning electron microscope observation.Therefore,highly sta-ble performance(158.4 mA h g^(-1) at 2 C after 200 cycles with a capacity retention of 95.24%)in Li@LCP-Cu||NCM811 coin cell can be achieved.Furthermore,the solid-state battery assembled with the hybrid anode,poly(vinylidene fluoride)(PVDF)-based polymer electrolyte and polyethylene oxide(PEO)interface functional layer also exhibits the best electrochemical and safety performance,which also proves that the Li@LCP-Cu anode has great potential for application in solid-state batteries.展开更多
In this work,a modification method of H_(3)PO_(4)plus H_(2)O_(2)(PHP)was introduced to targetedly form abundant oxygenated functional groups(OFGs)on biochar,and methylene blue(MB)was employed as a model pollutant for ...In this work,a modification method of H_(3)PO_(4)plus H_(2)O_(2)(PHP)was introduced to targetedly form abundant oxygenated functional groups(OFGs)on biochar,and methylene blue(MB)was employed as a model pollutant for adsorption to reflect the modification performance.Results indicated that parent biochars,especially derived from lower temperatures,substantially underwent oxidative modification by PHP,and OFGs were targetedly produced.Correspondingly,approximately 21.5-fold MB adsorption capacity was achieved by PHP-modified biochar comparing with its parent biochar.To evaluate the compatibility of PHP-modification,coefficient of variation(CV)based on MB adsorption capacity by the biochar from various precursors was calculated,in which the CV of PHP-modified biochars was 0.0038 comparing to0.64 of the corresponding parent biochars.These results suggested that the PHP method displayed the excellent feedstock compatibility on biochar modification.The maximum MB adsorption capacity was454.1 mg/g when the H_(3)PO_(4)and H_(2)O_(2)fraction in PHP were 65.2%and 7.0%;the modification was further intensified by promoting temperature and duration.Besides,average 94.5%H_(3)PO_(4)was recovered after 10-batch modification,implying 1.0 kg H_(3)PO_(4)(85%)in PHP can maximally modify 2.37 kg biochar.Overall,this work offered a novel method to tailor biochar towards OFGs-rich surface for efficient adsorption.展开更多
The effects of disinfection efficiency on microbial communities and the corrosion of cast iron pipes in drinking water distribution systems(DWDSs) were studied.Two annular reactors(ARs) that simulated actual running c...The effects of disinfection efficiency on microbial communities and the corrosion of cast iron pipes in drinking water distribution systems(DWDSs) were studied.Two annular reactors(ARs) that simulated actual running conditions with UV/Cl2 disinfection and chlorination alone were used.High chlorine consumption and corrosion rate were found in the AR with UV/Cl2.According to functional genes and pyrosequencing tests, a high percentage of iron recycling bacteria was detected within the biofilm of the AR with Cl2 at early running stage, whereas siderophore-producing bacteria were dominant in the biofilm of the AR with UV/Cl2.At the early running stage, the sequential use of UV light and an initial high chlorine dosage suppressed the biomass and iron-recycling bacteria in both bulk water and biofilms, thereby forming less protective scales against further corrosion, which enhanced chlorine consumption.Non-metric multidimensional scaling analysis showed that the bacterial communities in the ARs shaped from within rather than being imported by influents.These results indicate that the initial high disinfection efficiency within the distribution system had not contributed to the accumulation of iron-recycling bacteria at the early running stages.This study offer certain implications for controlling corrosion and water quality in DWDSs.展开更多
Gear fault diagnosis technologies have received rapid development and been effectively implemented in many engineering applications.However,the various working conditions would degrade the diagnostic performance and m...Gear fault diagnosis technologies have received rapid development and been effectively implemented in many engineering applications.However,the various working conditions would degrade the diagnostic performance and make gear fault diagnosis(GFD)more and more challenging.In this paper,a novel model parameter transfer(NMPT)is proposed to boost the performance of GFD under varying working conditions.Based on the previous transfer strategy that controls empirical risk of source domain,this method further integrates the superiorities of multi-task learning with the idea of transfer learning(TL)to acquire transferable knowledge by minimizing the discrepancies of separating hyperplanes between one specific working condition(target domain)and another(source domain),and then transferring both commonality and specialty parameters over tasks to make use of source domain samples to assist target GFD task when sufficient labeled samples from target domain are unavailable.For NMPT implementation,insufficient target domain features and abundant source domain features with supervised information are fed into NMPT model to train a robust classifier for target GFD task.Related experiments prove that NMPT is expected to be a valuable technology to boost practical GFD performance under various working conditions.The proposed methods provides a transfer learning-based framework to handle the problem of insufficient training samples in target task caused by variable operation conditions.展开更多
Although the degradation mechanism of straw anaerobic digestion is still obscure,lower temperature thermop hysical pretreatment might be a feasible way to improve biogas fermentation efficiency and net energy producti...Although the degradation mechanism of straw anaerobic digestion is still obscure,lower temperature thermop hysical pretreatment might be a feasible way to improve biogas fermentation efficiency and net energy production in whole slurry.In this study,the performances of rice straw(RS)degradation and biogas production were examined at different pretreatment temperatures from 90 ℃ to 130℃ to identify the optimal process.With increasing pretreatment temperature,the change in cellulose and hemicellulose degradation in all the tests was directly related to volatile fatty acids(VFAs)content,but did not correspond to the variation in cumulative methane production.Both 100℃ and 130℃presented similar ideal digestion performances with highest methane yields of 127.6 and 124.6 mL/g TS,respectively,which were 22.80%and 19.83%higher than that noted in the control.Although test at 100 ℃pretreatment,which achieved 12.8%higher net energy production from RS than that observed in the control,could be considered as the optimal choice,the surplus biogas could only meet 75.9%of energy requirement for pretreated water temperature shift.Nevertheless,mesophilic or thermophilic fermentation,lower pretreatment water input,and reuse of excess heat are recommended as feasible working conditions for improving net biogas production.展开更多
基金supported by the CAMS Innovation Fund for Medical Sciences(CIFMS)[grant number 2021-I2M-1-037]the National Natural Science Foundation of China[grant numbers 82373647,and 82473697].
文摘Objective This study aimed to explore the association between body mass index(BMI)and mortality based on the 10-year population-based multicenter prospective study.Methods A general population-based multicenter prospective study was conducted at four sites in rural China between 2013 and 2023.Multivariate Cox proportional hazards models and restricted cubic spline analyses were used to assess the association between BMI and mortality.Stratified analyses were performed based on the individual characteristics of the participants.Results Overall,19,107 participants with a sum of 163,095 person-years were included and 1,910 participants died.The underweight(<18.5 kg/m^(2))presented an increase in all-cause mortality(adjusted hazards ratio[aHR]=2.00,95%confidence interval[CI]:1.66–2.41),while overweight(≥24.0 to<28.0 kg/m^(2))and obesity(≥28.0 kg/m^(2))presented a decrease with an aHR of 0.61(95%CI:0.52–0.73)and 0.51(95%CI:0.37–0.70),respectively.Overweight(aHR=0.76,95%CI:0.67–0.86)and mild obesity(aHR=0.72,95%CI:0.59–0.87)had a positive impact on mortality in people older than 60 years.All-2 cause mortality decreased rapidly until reaching a BMI of 25.7 kg/m(aHR=0.95,95%CI:0.92–0.98)and increased slightly above that value,indicating a U-shaped association.The beneficial impact of being overweight on mortality was robust in most subgroups and sensitivity analyses.Conclusion This study provides additional evidence that overweight and mild obesity may be inversely related to the risk of death in individuals older than 60 years.Therefore,it is essential to consider age differences when formulating health and weight management strategies.
基金supported by funds from National Key Research and Development Program of China (2019YFA0904500 to LX, 2023YFA1800400 to LX, and 2018YFE0113500 to JX)the National Natural Science Foundation of China (82301777 to MG, 32222024 to LX, 32325024 to XM, 32071148 to LX, and 91957116 to CX)+6 种基金Fundamental Research Funds for the Central Universities, Science and Technology Commission of Shanghai Municipality (21140904300 to XM and 22ZR1421200 to LX)Innovation Program of Shanghai Municipal Education Commission (2017-01-07-00-09-E00042 to JX)Key Project of 2022 Higher Education Scientific Research Planning Project of China Association of Higher Education (22TY0218 to FS)Youth Fund for Humanities and Social Sciences Research of the Ministry of Education (22YJC890023 to FS)Postdoctoral Fellowship Program of CPSF (GZB20230219 to MG)China Postdoctoral Science Foundation (2023M741183 to MG)ECNU public platform for Innovation (011).
文摘Background: Resistance exercise leads to improved muscle function and metabolic homeostasis.Yet how circadian rhythm impacts exercise outcomes and its molecular transduction remains elusive.Methods: Human volunteers were subjected to 4 weeks of resistance training protocols at different times of day to assess training outcomes and their associations with myokine irisin.Based on rhythmicity of Fibronectin type III domain containing 5(FNDC5/irisin),we trained wild type and FNDC5 knockout mice at late active phase(high FNDC5/irisin level)or late rest phase(low FNDC5/irisin level)to analyze exercise benefits on muscle function and metabolic homeostasis.Molecular analysis was performed to understand the regulatory mechanisms of FNDC5 rhythmicity and downstream signaling transduction in skeletal muscle.Results: In this study,we showed that regular resistance exercises performed at different times of day resulted in distinct training outcomes in humans,including exercise benefits and altered plasma metabolomics.We found that muscle FNDC5/irisin levels exhibit rhythmicity.Consistent with human data,compared to late rest phase(low irisin level),mice trained chronically at late active phase(high irisin level)gained more muscle capacity along with improved metabolic fitness and metabolomics/lipidomics profiles under a high-fat diet,whereas these differences were lost in FNDC5 knockout mice.Mechanistically,Basic helix-loop-helix ARNT like 1(BMAL1)and Peroxisome proliferative activated receptor,gamma,coactivator 1 alpha 4(PGC1α4)induce FNDC5/irisin transcription and rhythmicity,and the signaling is transduced viaαV integrin in muscle.Conclusion: Together,our results offered novel insights that exercise performed at distinct times of day determines training outcomes and metabolic benefits through the rhythmic regulation of the BMAL1/PGC1α4-FNDC5/irisin axis.
基金financially supported by the Natural Science Basic Research Program of Shaanxi Province(No.2024JC-YBQN-0582)the Natural Science Foundation of Shaanxi Provincial Department of Education(No.23JK0702)+1 种基金Scientific Research fund of Xijing University(No.XJ23B05)the Fundamental Research Funds for the Central Universities(No.xzy012024005)。
文摘Lithium metal batteries face serious safety challenges caused by flammable organic electrolytes and the growth of lithium dendrite.Trimethyl phosphate(TMP)is a promising alternative for flammable carbonate electrolyte solvents owing to its nonflammable nature.But the low-concentration TMP-based electrolyte is unstable with the lithium metal anode.Here,a TMP-contained quasisolid electrolyte(PIQSE)with porous polyimide(PI)as supporting skeleton is designed.The cross-linking structure generated by UV curing in PIQSE can lock the reactive TMP solvent to reduce its contact with Li metal.Besides,the PI supporting skeleton with high-temperature resistance can significantly enhance the thermal stability of PIQSE.The combination of PI and TMP prompts the high ionic conductivity and excellent nonflammability of PIQSE.The LiFePO_(4)/Li cell using PIQSE shows superior electrochemical performance in a wide temperature range from-10 to 60°C.Furthermore,the cells with highvoltage cathode of LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)were matched with PIQSE exhibit good cyclic and rate performance.The NCM622/PIQSE/Li pouch cell was also fabricated.It exhibits a high discharge capacity of 182.9mAh.g^(-1),and can stably light up LEDs after folding and shearing tests,demonstrating broad prospects for highly safe energy storage applications.
基金financially supported by the National Natural Science Foundation of China(No.22209101)National Key R&D Program of China(No.2020YFA0710500)the Key Research and Development Program of Shaanxi(No.2022GXLH-01-23)for financial support。
文摘Owing to uncontrolled and uneven electrodeposition and side reactions,Zn metal anodes inevitably suffer from issues such as dendrite growth,hydrogen evolution reactions,and surface passivation.This paper proposes an efficient strategy to address these critical issues for realizing long-life and high-capacity aqueous zinc-ion hybrid supercapacitors(ZHSCs)by incorporating low-concentration(0.05 mol·L^(-1))redox RbI electrolyte additives.Specifically,rubidium cations have the ability to influence the negative Zn electrode surface via an electrostatic shielding mechanism,effectively protecting the electrode and minimizing undesired side reactions.In an aqueous solution,iodide anions actively solvate Zn^(2+)ions by stabilizing and modulating the solvation shell surrounding Zn^(2+).Moreover,the presence of iodide ions promotes the uniform deposition of Zn^(2+)species by selective adsorption onto the electrode surface.The synergistic effect of the electrostatic shielding and halogen ions enables the realization of aqueous symmetric Zn||Zn cells with a substantial cycle life of more than 2000 h Additionally,when applied to commercial activated carbon(AC),the proposed strategy facilitates the development of aqueous ZHSCs,exhibiting high specific capacitances(148.8 F·g^(-1)at 4 A·g^(-1))and ultra-long cycling stability.
基金financial support from National Key R&D Program of China(No.2022YFC2806904)National Natural Science Foundation of China(Nos.12372098,12332006,and 12021002).
文摘A theoretical model is developed to investigate the sliding electrical contact behavior with the consideration of the electrical-thermal–mechanical coupling effect.The interfacial electrical resistance and electrical constriction resistance are both involved.The Joule heating due to electrical contact resistance and the frictional energy dissipation are considered in the model for the assessment of the temperature rise at the contact interface.A singular integral equation for sliding electrical contact considering both frictional and Joule heat is developed and solved to obtain the contact pressure,current density,and temperature rise.Furthermore,a discrete fast Fourier transform-based boundary element method is applied to obtain the numerical solution of sliding electrical contact.Good agreement is achieved between theoretical and numerical results.After the validation,the effects of potential drop and sliding velocity on sliding electrical contact behavior are investigated.The results indicate that the proposed theoretical model can provide an exact prediction of multi-physics sliding electrical contact behavior.
基金supported by National Natural Science Foundation of China (Nos. 61503378, 61473293, 51405485 and 61403378)the Project of Development in Tianjin for Scientific Research Institutes, and Tianjin Government (No. 16PTYJGX00050)
文摘Object contour plays an important role in fields such as semantic segmentation and image classification. However, the extraction of contour is a difficult task, especially when the contour is incomplete or unclosed. In this paper, the existing contour detection approaches are reviewed and roughly divided into three categories： pixel-based, edge-based, and region-based. In addition, since the traditional contour detection approaches have achieved a high degree of sophistication, the deep convolutional neural networks （DCNNs） have good performance in image recognition, therefore, the DCNNs based contour detection approaches are also covered in this paper. Moreover, the future development of contour detection is analyzed and predicted.
基金financially supported by the National Natural Science Foundation of China(No.51772241)the Key Research Program of Shaanxi Province(No.2017ZDXM-GY-035)+2 种基金the Young Talent Support Plan of Xi’an Jiaotong University(No.DQ1J006)the Project from State Key Laboratory of Electrical Insulation and Power Equipment,Xi’an Jiaotong University(No.EIPE17306)the Fundamental Research Funds for the Central Universities(Nos.zrzd2017004,xjj2017076)for financial support
文摘Lithium （Li） metal has been considered as the most attractive anode materials for Li-ion batteries （LIBs） due to its high theoretic specific capacity. The formation of unstable solid electrolyte interphase （SEI） and dendritic Li on the metal anode, however, hindered its practical application. Herein, to address the issues, a Li-free electrode with ultrathin Al2O3 coated on reduced graphene oxide （rGO） membrane that covers a Cu foil current collector was developed. The composite electrode exhibits excellent interfacial protection of lithium metal deposited between Cu foil and rGO electrochemically. Firstly, it affords good Li^＋ permeability from the electrolyte. Secondly, the ultrathin Al2O3 has sufficient mechanical strength to inhibit the penetration of Li dendrite. Li metal was observed uniformly deposited between rGO membrane and Cu collector, and stable cycle performance of Li plating/stripping with Coulombic efficiency of ~ 91.75% at the lOOth cycle is achieved in organic carbonate electrolyte without any additives.
基金Supported by National Natural Science Foundation of China(Grant No.51575102)Jiangsu Postgraduate Research Innovation Program(Grant No.KYCX18_0075).
文摘Most gear fault diagnosis(GFD)approaches su er from ine ciency when facing with multiple varying working conditions at the same time.In this paper,a non-negative matrix factorization(NMF)-theoretic co-clustering strategy is proposed specially to classify more than one task at the same time using the high dimension matrix,aiming to o er a fast multi-tasking solution.The short-time Fourier transform(STFT)is first used to obtain the time-frequency features from the gear vibration signal.Then,the optimal clustering numbers are estimated using the Bayesian information criterion(BIC)theory,which possesses the simultaneous assessment capability,compared with traditional validity indexes.Subsequently,the classical/modified NMF-based co-clustering methods are carried out to obtain the classification results in both row and column tasks.Finally,the parameters involved in BIC and NMF algorithms are determined using the gradient ascent(GA)strategy in order to achieve reliable diagnostic results.The Spectra Quest’s Drivetrain Dynamics Simulator gear data sets were analyzed to verify the e ectiveness of the proposed approach.
基金supported by the National Natural Science Foundation of China(No.11002010)
文摘A new continuum damage mechanics model for fretting fatigue life prediction is established. In this model, the damage evolution rate is described by two kinds of quantities. One is associated with the cyclic stress characteristics obtained by the finite element （FE） analysis, and the other is associated with the material fatigue property identified from the fatigue test data of standard specimens. The wear is modeled by the energy wear law to simulate the contact geometry evolution. A two-dimensional （2D） plane strain FE implementation of the damage mechanics model and the energy wear model is presented in the platform of ABAQUS to simulate the evolutions of the fatigue damage and the wear scar. The effect of the specimen thickness is also investigated. The predicted results of the crack initiation site and the fretting fatigue life agree well with available experimental data. Comparisons are made with the critical plane Smith- Watson-Topper （SWT） method.
基金supported by the National Natural Science Foundation of China(No.11002010)
文摘An approach based on continuum damage mechanics to fatigue life prediction for structures is proposed. A new fatigue damage evolution equation is developed, in which the pa- rameters are obtained in a simple way with reference to the experimental results of fatigue tests on standard specimens. With the utilization of APDL language on the ANSYS platform, a finite element implementation is presented to perform coupling operation on damage evolution of mate- rial and stress redistribution. The fatigue lives of some notched specimens and a Pitch-change-link are predicted by using the above approach. The calculated results are validated with experimental data.
基金financial support by National Natural Science Foundation of China(Nos.22176019,51978110)the Science and Technology Research Program of Chongqing Municipal Education Commission(Nos.KJQN201800829,KJQN201900837,KJZD-K202000802,KJQN201901527)+1 种基金Chongqing Research Student Science and Technology Innovation Project(No.CYS22724)Innovation and Entrepreneurship Training Plan for College Students(No.202111799007).
文摘This work reported a facile approach to surface oxygen vacancy(O_(v))-enriched urchin-like TiO_(2) microparticles(U-TiO_(2)),which were highly effective and durable in catalyzing selective nitrate reduction to ammonia(NOgRR),Specifically,the U-TiO_(2)delivered a mass activity of 1.15 min^(-1)mg^(-1)calyst.a low yield of toxic NO_(2)^(-)-N intermediate(≤0.4mg/L)and an exceptional high NH_(3)^(-)-N selectivity of 98.1%in treating 22.5 mg/L of NO_(3)^(-)-N under a potential of-0.60V vs.RHE,outperforming most of the reported oxidebased catalysts.When comparing the performance of U-TiO_(2)with that of the solid amorphous TiO_(2) counterpart(A-TiO_(2))that had close particle size but more O_(v) on surfaces,we identified that the O_(v) was the reactive sites,but rather than its content,the NO_(3)RR kinetics were primarily limited by the electron and mass transfer at U-TiO_(2)/water interfaces.Accordingly,the superior performance of U-TiO_(2)to A-TiO_(2)could be ascribed to the hierarchical urchin-like structure in U-TiO_(2).The in-situ DEMS test revealed that the NO_(3)RR on U-TiO_(2)followed a pathway of ^(*)NO_(3)^(-)→^(*)NO_(2)^(-)→^(*)NO→^(*)N→^(*)NH^(-)→^(*)NH_(2)→^(*)NH_(3).We also demonstrated that the U-TiO_(2) could keep its robust performance under a wide NO_(3)^(-)-N concentration range and in the presence of some co-existing ions(such as Ca^(2+),Cl^(-),Mg^(2+)).However,the presence of humic acid and CO_(3)^(2-) in water slowed down the NO_(3)RR on U-TiO_(2).This work provides a more fundamental insight into the O_(v)-driven NO_(3)RR process on TiO_(2),which should benefit for the development of eficient TiO_(2)-based catalvsts.
基金supported by the National Key R&D Program of China (Grant No.2020YFA0710500)The authors acknowledge the basic scientific research business expenses Program of Xi’an Jiaotong University (Grant No.xzy022022053)the Independent Research Project of the State Key Laboratory of Electrical Insulation and Power Equipment (Grant No.EIPE23303)for financial support.
文摘Safety issues induced by infinite anode volume change and uncontrolled lithium(Li)dendrite growth have become the biggest obstacle to the practical application of Li metal batteries.In addition,the tra-ditional rolling method makes it difficult to manufacture thin Li foil with high mechanical strength and low Li content.Herein,a three-dimensional(3D)lithophilic carbon paper/copper(Cu)current collector hybrid anode with ultra-low Li metal content is prepared by a hot-pressing method.The highly re-versible and stable lithiophilic layer LiC_(x) formed in situ by heating/pressing treatment provides abun-dant nucleation sites and reduces the Li nucleation overpotential,thereby effectively suppressing Li den-drite growth.Moreover,the volume change and pulverization problems of Li metal anode during depo-sition/stripping also can be accommodated by the 3D skeleton.The optimization effect has been directly confirmed by in-situ optical and ex-situ scanning electron microscope observation.Therefore,highly sta-ble performance(158.4 mA h g^(-1) at 2 C after 200 cycles with a capacity retention of 95.24%)in Li@LCP-Cu||NCM811 coin cell can be achieved.Furthermore,the solid-state battery assembled with the hybrid anode,poly(vinylidene fluoride)(PVDF)-based polymer electrolyte and polyethylene oxide(PEO)interface functional layer also exhibits the best electrochemical and safety performance,which also proves that the Li@LCP-Cu anode has great potential for application in solid-state batteries.
基金the National Natural Science Foundation of China(No.21978183)。
文摘In this work,a modification method of H_(3)PO_(4)plus H_(2)O_(2)(PHP)was introduced to targetedly form abundant oxygenated functional groups(OFGs)on biochar,and methylene blue(MB)was employed as a model pollutant for adsorption to reflect the modification performance.Results indicated that parent biochars,especially derived from lower temperatures,substantially underwent oxidative modification by PHP,and OFGs were targetedly produced.Correspondingly,approximately 21.5-fold MB adsorption capacity was achieved by PHP-modified biochar comparing with its parent biochar.To evaluate the compatibility of PHP-modification,coefficient of variation(CV)based on MB adsorption capacity by the biochar from various precursors was calculated,in which the CV of PHP-modified biochars was 0.0038 comparing to0.64 of the corresponding parent biochars.These results suggested that the PHP method displayed the excellent feedstock compatibility on biochar modification.The maximum MB adsorption capacity was454.1 mg/g when the H_(3)PO_(4)and H_(2)O_(2)fraction in PHP were 65.2%and 7.0%;the modification was further intensified by promoting temperature and duration.Besides,average 94.5%H_(3)PO_(4)was recovered after 10-batch modification,implying 1.0 kg H_(3)PO_(4)(85%)in PHP can maximally modify 2.37 kg biochar.Overall,this work offered a novel method to tailor biochar towards OFGs-rich surface for efficient adsorption.
基金supported by the National Natural Science Foundation of China(Nos.31771726,51708372)the project of Agriculture Research System of China(No.CARS-18).
文摘The effects of disinfection efficiency on microbial communities and the corrosion of cast iron pipes in drinking water distribution systems(DWDSs) were studied.Two annular reactors(ARs) that simulated actual running conditions with UV/Cl2 disinfection and chlorination alone were used.High chlorine consumption and corrosion rate were found in the AR with UV/Cl2.According to functional genes and pyrosequencing tests, a high percentage of iron recycling bacteria was detected within the biofilm of the AR with Cl2 at early running stage, whereas siderophore-producing bacteria were dominant in the biofilm of the AR with UV/Cl2.At the early running stage, the sequential use of UV light and an initial high chlorine dosage suppressed the biomass and iron-recycling bacteria in both bulk water and biofilms, thereby forming less protective scales against further corrosion, which enhanced chlorine consumption.Non-metric multidimensional scaling analysis showed that the bacterial communities in the ARs shaped from within rather than being imported by influents.These results indicate that the initial high disinfection efficiency within the distribution system had not contributed to the accumulation of iron-recycling bacteria at the early running stages.This study offer certain implications for controlling corrosion and water quality in DWDSs.
基金Supported by National Natural Science Foundation of China(Grant No.51835009).
文摘Gear fault diagnosis technologies have received rapid development and been effectively implemented in many engineering applications.However,the various working conditions would degrade the diagnostic performance and make gear fault diagnosis(GFD)more and more challenging.In this paper,a novel model parameter transfer(NMPT)is proposed to boost the performance of GFD under varying working conditions.Based on the previous transfer strategy that controls empirical risk of source domain,this method further integrates the superiorities of multi-task learning with the idea of transfer learning(TL)to acquire transferable knowledge by minimizing the discrepancies of separating hyperplanes between one specific working condition(target domain)and another(source domain),and then transferring both commonality and specialty parameters over tasks to make use of source domain samples to assist target GFD task when sufficient labeled samples from target domain are unavailable.For NMPT implementation,insufficient target domain features and abundant source domain features with supervised information are fed into NMPT model to train a robust classifier for target GFD task.Related experiments prove that NMPT is expected to be a valuable technology to boost practical GFD performance under various working conditions.The proposed methods provides a transfer learning-based framework to handle the problem of insufficient training samples in target task caused by variable operation conditions.
基金financial support from Special Fund for Agro-scientific Research in the Public Interest(No. 201403019)Integrated Rural Energy Development Project of MOA(No. J576)+2 种基金the Sichuan Province Science and Technology Support Project (No. 18RKX0185)the International Clean Energy Talent Program of China Scholarship Council (No. 201802180094)the Agricultural Science Technology Innovation Program (ASTIP) of the Chinese Academy of Agricultural Sciences
文摘Although the degradation mechanism of straw anaerobic digestion is still obscure,lower temperature thermop hysical pretreatment might be a feasible way to improve biogas fermentation efficiency and net energy production in whole slurry.In this study,the performances of rice straw(RS)degradation and biogas production were examined at different pretreatment temperatures from 90 ℃ to 130℃ to identify the optimal process.With increasing pretreatment temperature,the change in cellulose and hemicellulose degradation in all the tests was directly related to volatile fatty acids(VFAs)content,but did not correspond to the variation in cumulative methane production.Both 100℃ and 130℃presented similar ideal digestion performances with highest methane yields of 127.6 and 124.6 mL/g TS,respectively,which were 22.80%and 19.83%higher than that noted in the control.Although test at 100 ℃pretreatment,which achieved 12.8%higher net energy production from RS than that observed in the control,could be considered as the optimal choice,the surplus biogas could only meet 75.9%of energy requirement for pretreated water temperature shift.Nevertheless,mesophilic or thermophilic fermentation,lower pretreatment water input,and reuse of excess heat are recommended as feasible working conditions for improving net biogas production.
