This study proposes a pre-strain optimization strategy for carbon fiber structural lithium-ion battery(SLIB) composites to inhibit the interfacial debonding between carbon fibers and solid-state electrolytes due to fi...This study proposes a pre-strain optimization strategy for carbon fiber structural lithium-ion battery(SLIB) composites to inhibit the interfacial debonding between carbon fibers and solid-state electrolytes due to fiber lithiation. Through an analytical shear-lag model and finite element simulations, it is demonstrated that applying tensile pre-strain to carbon fibers before electrode assembly effectively reduces the interfacial shear stress, thereby suppressing debonding. However, the excessive pre-strain can induce the interfacial damage in the unlithiated state, necessitating careful control of the pre-strain within a feasible range. This range is influenced by electrode material properties and geometric parameters. Specifically, the electrodes with the higher solid-state electrolyte elastic modulus and larger electrolyte volume fraction exhibit more significant interfacial damage, making pre-strain application increasingly critical. However, these conditions also impose stricter constraints on the feasible pre-strain range. By elucidating the interplay between pre-strain, material properties, and geometric factors, this study provides valuable insights for optimizing the design of carbon fiber SLIBs.展开更多
The recently reported silicon/graphite(Si/Gr)composite electrode with a layered structure is a promising approach to achieve high capacity and stable cycling of Si-based electrodes in lithium-ion batteries.However,the...The recently reported silicon/graphite(Si/Gr)composite electrode with a layered structure is a promising approach to achieve high capacity and stable cycling of Si-based electrodes in lithium-ion batteries.However,there is still a need to clarify why particular layered structures are effective and why others are ineffective or even detrimental.In this work,an unreported mechanism dominated by the porosity evolution of electrodes is proposed for the degradation behavior of layered Si/Gr electrodes.First,the effect of layering sequence on the overall electrode performance is investigated experimentally,and the results suggest that the cycling performance of the silicon-on-graphite(SG)electrode is much superior to that of the graphite-on-silicon electrode.To explain this phenomenon,a coupled mechanical-electrochemical porous electrode model is developed,in which the porosity is affected by the silicon expansion and the local constraints.The modeling results suggest that the weaker constraint of the silicon layer in the SG electrode leads to a more insignificant decrease in porosity,and consequently,the more stable cycling performance.The findings of this work provide new insights into the structural design of Si-based electrodes.展开更多
Micro aerial vehicles(MAVs)have flexibility and maneuverability,which can offer vast potential for applications in both civilian and military domains.Compared to Fixed-wing/Rotor-wing MAVs,Flapping Wing Micro Robots(F...Micro aerial vehicles(MAVs)have flexibility and maneuverability,which can offer vast potential for applications in both civilian and military domains.Compared to Fixed-wing/Rotor-wing MAVs,Flapping Wing Micro Robots(FWMRs)have garnered widespread attention among scientists due to their superior miniaturized aerodynamic theory,reduced noise,and enhanced resistance to disturbances in complex and diverse environments.Flying insects,it not only has remarkable flapping flight ability(wings),but also takeoff and landing habitat ability(legs).If the various functions of flying insects can be imitated,efficient biomimetic FWMRs can be produced.This paper provides a review of the flight kinematics,aerodynamics,and wing structural parameters of insects.Then,the traditional wings and folding wings of insect-inspired FWMRs were compared.The research progress in takeoff and landing of FWMRs was also summarized,and the future developments and challenges for insect-inspired FWMRs were discussed.展开更多
Emergence refers to the existence or formation of collective behaviors in complex systems.Here,we develop a theoretical framework based on the eigen microstate theory to analyze the emerging phenomena and dynamic evol...Emergence refers to the existence or formation of collective behaviors in complex systems.Here,we develop a theoretical framework based on the eigen microstate theory to analyze the emerging phenomena and dynamic evolution of complex system.In this framework,the statistical ensemble composed of M microstates of a complex system with N agents is defined by the normalized N×M matrix A,whose columns represent microstates and order of row is consist with the time.The ensemble matrix A can be decomposed as■,where r=min(N,M),eigenvalueσIbehaves as the probability amplitude of the eigen microstate U_I so that■and U_I evolves following V_I.In a disorder complex system,there is no dominant eigenvalue and eigen microstate.When a probability amplitudeσIbecomes finite in the thermodynamic limit,there is a condensation of the eigen microstate UIin analogy to the Bose–Einstein condensation of Bose gases.This indicates the emergence of U_I and a phase transition in complex system.Our framework has been applied successfully to equilibrium threedimensional Ising model,climate system and stock markets.We anticipate that our eigen microstate method can be used to study non-equilibrium complex systems with unknown orderparameters,such as phase transitions of collective motion and tipping points in climate systems and ecosystems.展开更多
In this paper,a model of activated carbon was established by molecular simulation and the separation performance of N2 and CH4 on activated carbon was studied.In order to evaluate the adsorption selectivity and diffus...In this paper,a model of activated carbon was established by molecular simulation and the separation performance of N2 and CH4 on activated carbon was studied.In order to evaluate the adsorption selectivity and diffusion selectivity of N2 and CH4,Grand Canonical Monte Carlo and molecular dynamic methods were used to obtain equilibrium adsorption isotherms and mean square displacements of N2 and CH4 on activated carbon with different pore sizes.Research results showed that the difference in adsorption isosteric heat of N2 and CH4 at the pore size of 0.46 nm is the largest,which is 5.759 and 7.03 kcal·mol^-1(1 cal=4.184 J),respectively.Activated carbon with pore size of 0.46 nm has the best N2 and CH4 adsorption selectivity,while its diffusion selectivity is not obvious.展开更多
BACKGROUND:Acute liver failure(ALF) caused by viral and non-viral hepatitis is often accompanied with severe metabolic disorders,the accumulation of toxic substances and continuous release and accumulation of a large ...BACKGROUND:Acute liver failure(ALF) caused by viral and non-viral hepatitis is often accompanied with severe metabolic disorders,the accumulation of toxic substances and continuous release and accumulation of a large number of endogenous toxins and inflammatory mediators. The present study aimed to investigate the effects of various combined non-biological artif icial liver treatments for patients with acute liver failure(ALF) complicated by multiple organ dysfunction syndrome(MODS).METHODS:Thirty-one patients with mid- or late-stage liver failure complicated by MODS(score 4) were randomly divided into three treatment groups:plasmapheresis(PE) combined with hemoperfusion(HP) and continuous venovenous hemodiafiltration(CVVHDF),PE+CVVHDF,and HP+CVVHDF,respectively. Heart rate(HR) before and after treatment,mean arterial pressure(MAP),respiratory index(PaO2/FiO2),hepatic function,platelet count,and blood coagulation were determined.RESULTS:Signifi cant improvement was observed in HR,MAP,PaO2/FiO2,total bilirubin(TBIL) and alanine aminotransferase(ALT) levels after treatment(P<0.05). TBIL and ALT decreased more signifi cantly after treatment in the PE+CVVHDF and PE+HP+CVVHDF groups(P<0.01). Prothrombin time(PT) and albumin were signifi cantly improved only in the PE+CVVHDF and PE+HP+CVVHDF groups(P<0.05). TBIL decreased more significantly in the PE+HP+CVVHDF group than in the HP+CVVHDF and PE+CVVHDF groups(P<0.05). The survival rate of the patients was 58.1%(18/31),viral survival rate 36.4%(4/11),and non-viral survival rate 70%(14/20).CONCLUSION:Liver function was relatively improved after treatment,but PE+HP+CVVHDF was more efficient for the removal of toxic metabolites,especially bilirubin. The survival rate was signifi cantly higher in the patients with non-viral liver failure than in those with viral liver failure.展开更多
In anode free batteries(AFBs), the current collector acts as anode simultaneously and has large volume expansion which is generally considered as a negative effect decreasing the structural stability of a battery. Mor...In anode free batteries(AFBs), the current collector acts as anode simultaneously and has large volume expansion which is generally considered as a negative effect decreasing the structural stability of a battery. Moreover, despite many studies on the fast lithium diffusion in the current collector materials of AFB such as copper and aluminum, the involved Li diffusion mechanism in these materials remains poorly understood. Through first-principles calculation and stress-assisted diffusion equations, here we study the Li diffusion mechanism in several current collectors and related alloys and clarify the effect of volume expansion on Li diffusion respectively. It is suggested that due to the lower Li migration barriers in aluminum and tin, they should be more suitable to be used as AFB anodes, compared to copper, silver, and lead. The Li diffusion facilitation in copper with a certain number of vacancies is proposed to explain why the use of copper with a thickness≤100 nm as the protective coating on the anode improves the lifetime of the batteries. We show that the volume expansion has a positive effect on Li diffusion via mechanical–electrochemical coupling. Namely, the volume expansion caused by Li diffusion will further induce stress which in turn affects the diffusion. These findings not only provide in-depth insight into the operating principle of AFBs, but also open a new route toward design of improved anode through utilizing the positive effect of mechanical–electrochemical coupling.展开更多
Background:Hypertension,a prevalent disease,is a significant risk factor for coronary heart disease.Huoxue Qianyang Qutan Recipe (HQQR),a traditional Chinese herbal remedy,has been used for treating hypertension over ...Background:Hypertension,a prevalent disease,is a significant risk factor for coronary heart disease.Huoxue Qianyang Qutan Recipe (HQQR),a traditional Chinese herbal remedy,has been used for treating hypertension over several years.Objective:This study assesses HQQR’s efficacy for controlling blood pressure among patients with hypertension related to blood stasis,yang hyperactivity and phlegm.Design,setting,participants and interventions:A randomized controlled trial was conducted at the Yueyang Hospital of Integrated Traditional Chinese and Western Medicine,Shanghai University of Traditional Chinese Medicine,China,from July 2020 to June 2022.Major components of HQQR were identified using thin-layer chromatography and high-performance liquid chromatography.Participants aged18–80 years,exhibiting traditional Chinese medicine syndromes of blood stasis,yang hyperactivity or phlegm,along with grades 1 or 2 hypertension,were randomly categorized into two groups.The intervention group was given HQQR granules alongside conventional hypertension treatment,while the control group was given placebo granules in addition to conventional treatment for 12 weeks.Main outcome measures:The primary outcome was clinic blood pressure,whereas secondary outcomes included metabolic indices (e.g.,homeostasis model assessment of insulin resistance[HOMA-IR],total cholesterol[TC],low-density lipoprotein cholesterol and triglyceride),target organ damage indices (left ventricular mass index and urinary albumin creatinine ratio[UACR]) and inflammation indices(interleukin-6[IL-6]and high-sensitivity C-reactive protein[hs-CRP]).Results:HQQR’s primary components were identified as salvianolic acid B,emodin and ferulic acid.Of the 216 participants (108 in each group),compared to the control,the intervention group exhibited significant improvements (P<0.001) in clinic systolic blood pressure ([136.24±7.63]vs[130.06±8.50]mmHg),clinic diastolic blood pressure ([84.34±8.72]vs[80.46±6.05]mmHg),home systolic blood pressure([131.64±8.74]vs[122.36±8.45]mmHg) and home diastolic blood pressure ([78.47±9.53]vs[71.79±6.82]mm Hg).HQQR demonstrated a reduction in ambulatory blood pressure (24-hour systolic blood pressure:[133.75±10.49]vs[132.46±8.84]mmHg and 24-hour diastolic blood pressure:[84.12±8.01]vs[82.11±7.45]mmHg) and an improvement in HOMA-IR ([4.09±1.72]vs[3.98±1.44]),TC ([4.66±1.47]vs[3.75±1.81]mmol/L) and UACR (75.94[5.12,401.12]vs 45.61[4.26,234.26]).Moreover,HQQR demonstrated a decrease in hs-CRP (1.46[0.10,10.53]vs 0.57[0.12,3.99]mg/L) and IL-6 (6.69[2.00,29.74]vs 5.27[2.00,9.73]pg/mL),with no reported side effects (P<0.001).Conclusion:This study highlights the therapeutic potential of HQQR use in ameliorating blood pressure,glycolipid metabolism,and inflammation in patients with hypertension.展开更多
Luminescent cocrystals have been received much attention in fluorescence imaging and sensor application. In this work, we report that the high-quality chiral luminescent cocrystal can be obtained through a molecular s...Luminescent cocrystals have been received much attention in fluorescence imaging and sensor application. In this work, we report that the high-quality chiral luminescent cocrystal can be obtained through a molecular self-assembly process of 2,20-binaphthol and 2-（3-pyridyl）-1 H-benzimidazole. The assembly modes and stacking fashions of as-obtained cocrystal were determined by single crystal X-ray diffractometer. The structure and optical properties of the cocrystals were characterized by fluorescence emission, fluorescence decay, Raman and circular dichroism spectra. The results show that both the pristine co-assembled units（R-BINOL and S-BINOL） give rise to the R conformation within the final cocrystal, suggesting that the formation of cocrystal can be an effective way to achieve R/S-isomeric transformation of 2,20-binaphthol. It is also expected that the co-crystallization approach has much flexibility and potential applications for the design and selective formation of chiral luminescent materials.展开更多
Glycyrrhetic acid 3-O-mono-β-D-glucuronide （GAMG）, the major functional ingredient in licorice, has widespread applications in food, pharmacy and cosmetics industry. The production of GAMG through Penicillium purpu...Glycyrrhetic acid 3-O-mono-β-D-glucuronide （GAMG）, the major functional ingredient in licorice, has widespread applications in food, pharmacy and cosmetics industry. The production of GAMG through Penicillium purpurogenum Li-3 cultivation was for the first time performed through both batch and fed-batch processes in bioreactors. In batch process, under optimal conditions （pH 5.0, temperature 32℃, agitation speed 100 r. rain 1）, 3.55 g. L^-1 GAMG was obtained in a 2.5 L fermentor. To further enhance GAMG production, a fine fed-batch process was developed by using pH and DO as feedback parameters. Starting from 48 h, 100 m190 g-L 1 substrate Glycyrrhizin （GL） was fed each time when pH increased to above 5.0 and DO was increased to above 80%. This strategy can significantly enhance GAMG production： the achieved GL conversion was 95.34% with GAMG yield of 95.15%, and GAMG concentration was 16.62 g. L^-1 which was 5 times higher than that of batch. Then, a two-step separation strat- egy was established to separate GAMG from fermentation broth by crude extraction of 15 ml column packed with D10I resin followed by fine purification with preparative C18 chromatography. The obtained GAMG purity was 95.79%. This study provides a new insight into the industrial bioprocess of high-level GAMG production.展开更多
Electric vehicles(EVs)have garnered significant attention as a vital driver of economic growth and environmental sustainability.Nevertheless,ensuring the safety of high-energy batteries is now a top priority that cann...Electric vehicles(EVs)have garnered significant attention as a vital driver of economic growth and environmental sustainability.Nevertheless,ensuring the safety of high-energy batteries is now a top priority that cannot be overlooked during large-scale applications.This paper proposes an innovative active protection and cooling integrated battery module using smart materials,magneto-sensitive shear thickening fluid(MSTF),which is specifically designed to address safety threats posed by lithium-ion batteries(LIBs)exposed to harsh mechanical and environmental conditions.The theoretical framework introduces a novel approach for harnessing the smoothed-particle hydrodynamics(SPH)methodology that incorporates the intricate interplay of non-Newtonian fluid behavior,capturing the fluid-structure coupling inherent to the MSTF.This approach is further advanced by adopting an enhanced Herschel-Bulkley(H-B)model to encapsulate the intricate rheology of the MSTF under the influence of the magnetorheological effect(MRE)and shear thickening(ST)behavior.Numerical simulation results show that in the case of cooling,the MSTF is an effective cooling medium for rapidly reducing the temperature.In terms of mechanical abuse,the MSTF solidifies through actively applying the magnetic field during mechanical compression and impact within the battery module,resulting in 66%and 61.7%reductions in the maximum stress within the battery jellyroll,and 31.1%and 23%reductions in the reaction force,respectively.This mechanism effectively lowers the risk of short-circuit failure.The groundbreaking concepts unveiled in this paper for active protection battery modules are anticipated to be a valuable technological breakthrough in the areas of EV safety and lightweight/integrated design.展开更多
We report the production of ^(87)Rb Bose–Einstein condensate in an asymmetric crossed optical dipole trap(ACODT)without the need of an additional dimple laser.In our experiment,the ACODT is formed by two laser beams ...We report the production of ^(87)Rb Bose–Einstein condensate in an asymmetric crossed optical dipole trap(ACODT)without the need of an additional dimple laser.In our experiment,the ACODT is formed by two laser beams with different radii to achieve efficient capture and rapid evaporation of laser cooled atoms.Compared to the cooling procedure in a magnetic trap,the atoms are firstly laser cooled and then directly loaded into an ACODT without the pre-evaporative cooling process.In order to determine the optimal parameters for evaporation cooling,we optimize the power ratio of the two beams and the evaporation time to maximize the final atom number left in the ACODT.By loading about 6×10^(5) laser cooled atoms in the ACODT,we obtain a pure Bose–Einstein condensate with about 1.4×10^(4) atoms after 19 s evaporation.Additionally,we demonstrate that the fringe-type noises in optical density distributions can be reduced via principal component analysis,which correspondingly improves the reliability of temperature measurement.展开更多
The interfacial debonding between the active layer and the current collector has been recognized as a critical mechanism for battery fading,and thus has attracted great efforts focused on the related analyses.However,...The interfacial debonding between the active layer and the current collector has been recognized as a critical mechanism for battery fading,and thus has attracted great efforts focused on the related analyses.However,much still remains to be studied regarding practical methods for suppressing electrode debonding,especially from the perspective of mechanics.In this paper,a pre-strain strategy of current collectors to alleviate electrode debonding is proposed.An analytical model for a symmetric electrode with a deformable and limited-thickness current collector is developed to analyze the debonding behavior involving both a pre-strain of the current collector and an eigen-strain of the active layers.The results reveal that the well-designed pre-strain can significantly delay the debonding onset(by up to 100%)and considerably reduce the debonding size.The critical values of the pre-strain are identified,and the pre-strain design principles are also provided.Based on these findings,this work sheds light on the mechanical design to suppress electrode degradation.展开更多
The variation of the effective modulus of silicon composite electrodes,which is a fundamental feature to analyze the coupled mechanical–electrochemical behavior of Si-based electrodes in high-capacity lithium-ion bat...The variation of the effective modulus of silicon composite electrodes,which is a fundamental feature to analyze the coupled mechanical–electrochemical behavior of Si-based electrodes in high-capacity lithium-ion batteries,remains qualitatively controversial.To clarify the contradictory experimental results,numerical modeling of a representative volume element with silicon particles,carbon-binder domains(CBDs),and pores has been performed for the lithiation process.The key parameters for modulus variation were identified and evaluated.A mesostructure change is proposed to be a crucial mechanism that affects the modulus variation,and silicon softening is another key mechanism.Silicon softening and the decreasing CBD volume fraction collectively result in a decrease in the effective modulus of the composite,whereas an increase in the silicon volume fraction along with a decrease in porosity has the opposite effect.The findings of this work provide an in-depth and fundamental understanding of the mechanical properties of silicon composite electrodes.展开更多
Seizures are caused by increased neuronal firing activity resulting from reduced inhibitory effect and enhancement of inhibitory modulation to suppress this activity is used as a therapeutic tool.However,recent experi...Seizures are caused by increased neuronal firing activity resulting from reduced inhibitory effect and enhancement of inhibitory modulation to suppress this activity is used as a therapeutic tool.However,recent experiments have shown a counterintuitive phenomenon that inhibitory modulation does not suppress but elicit post-inhibitory rebound(PIR)spike along with seizure to challenge the therapeutic tool.The nonlinear mechanism to avoid the PIR spike can present theoretical guidance to seizure treatment.This paper focuses on identifying credible bifurcations that underlie PIR spike by modulating multiple parameters in multiple theoretical models.The study identifies a codimension-2 bifurcation called saddle-node homoclinic orbit(SNHOB),which is an intersection between saddle node bifurcation on invariant cycle(SNIC)and other two bifurcations.PIR spike cannot be evoked for the SNIC far from the SNHOBbut induced for the SNIC close to the SNHOB,which extends the bifurcation condition for PIR spike from the well-known Hopf to SNIC.Especially,in a thalamic neuron model,increases of conductance of T-type Ca^(2+)(TC a)channel induce SNIC bifurcation approaching to the SNHOB to elicit PIR spikes,closely matching experimental results of the absence seizure or Parkinson diseases.Such results imply that,when inhibition is employed to relieve absence seizure and Parkinson diseases related to PIR spike,modulating SNIC to get far from the SNHOBto avoid PIR spike is the principle.The study also addresses the complex roles of TCacurrent and comprehensive relationships between PIR spike and nonlinear conceptions such as bifurcation types and shapes of threshold curve.展开更多
The LE is the low energy telescope that is carried on Insight-HXMT.It uses swept charge devices(SCDs)to detect soft X-ray photons.LE’s time response is caused by the structure of the SCDs.With theoretical analysis an...The LE is the low energy telescope that is carried on Insight-HXMT.It uses swept charge devices(SCDs)to detect soft X-ray photons.LE’s time response is caused by the structure of the SCDs.With theoretical analysis and Monte Carlo simulations we discuss the influence of LE time response(LTR)on the timing analysis from three aspects:the power spectral density,the pulse profile and the time lag.After the LTR,the value of power spectral density monotonously decreases with the increasing frequency.The power spectral density of a sinusoidal signal reduces by a half at frequency 536 Hz.The corresponding frequency for quasi-periodic oscillation(QPO)signals is 458 Hz.The root mean square(RMS)of QPOs holds a similar behaviour.After the LTR,the centroid frequency and full width at half maxima(FWHM)of QPOs signals do not change.The LTR reduces the RMS of pulse profiles and shifts the pulse phase.In the time domain,the LTR only reduces the peak value of the cross-correlation function while it does not change the peak position;thus it will not affect the result of the time lag.When considering the time lag obtained from two instruments and one among them is LE,a 1.18 ms lag is expected caused by the LTR.The time lag calculated in the frequency domain is the same as that in the time domain.展开更多
In this paper,the authors obtain the existence of one-signed periodic solutions of the first-order functional difference equation ？u（n） = a（n）u（n）-λb（n）f（u（n-τ（n）））,n ∈ Z by using global bifurcation ...In this paper,the authors obtain the existence of one-signed periodic solutions of the first-order functional difference equation ？u（n） = a（n）u（n）-λb（n）f（u（n-τ（n）））,n ∈ Z by using global bifurcation techniques,where a,b：Z → [0,∞） are T-periodic functions with ∑T n=1 a（n） 〉 0,∑T n=1 b（n） 〉 0;τ：Z → Z is T-periodic function,λ 〉 0 is a parameter;f ∈ C（R,R） and there exist two constants s2 〈 0 〈 s1 such that f（s2） = f（0） = f（s1） = 0,f（s） 〉 0 for s ∈（0,s1） ∪（s1,∞）,and f（s） 〈 0 for s ∈（-∞,s2） ∪（s2,0）.展开更多
Imputation of missing data has long been an important topic and an essential application for intelligent transportation systems(ITS)in the real world.As a state-of-the-art generative model,the diffusion model has prov...Imputation of missing data has long been an important topic and an essential application for intelligent transportation systems(ITS)in the real world.As a state-of-the-art generative model,the diffusion model has proven highly successful in image generation,speech generation,time series modelling etc.and now opens a new avenue for traffic data imputation.In this paper,we propose a conditional diffusion model,called the implicit-explicit diffusion model,for traffic data imputation.This model exploits both the implicit and explicit feature of the data simultaneously.More specifically,we design two types of feature extraction modules,one to capture the implicit dependencies hidden in the raw data at multiple time scales and the other to obtain the long-term temporal dependencies of the time series.This approach not only inherits the advantages of the diffusion model for estimating missing data,but also takes into account the multiscale correlation inherent in traffic data.To illustrate the performance of the model,extensive experiments are conducted on three real-world time series datasets using different missing rates.The experimental results demonstrate that the model improves imputation accuracy and generalization capability.展开更多
基金supported by the National Natural Science Foundation of China(Nos.12172205,12072183,12102244,and 12472174)。
文摘This study proposes a pre-strain optimization strategy for carbon fiber structural lithium-ion battery(SLIB) composites to inhibit the interfacial debonding between carbon fibers and solid-state electrolytes due to fiber lithiation. Through an analytical shear-lag model and finite element simulations, it is demonstrated that applying tensile pre-strain to carbon fibers before electrode assembly effectively reduces the interfacial shear stress, thereby suppressing debonding. However, the excessive pre-strain can induce the interfacial damage in the unlithiated state, necessitating careful control of the pre-strain within a feasible range. This range is influenced by electrode material properties and geometric parameters. Specifically, the electrodes with the higher solid-state electrolyte elastic modulus and larger electrolyte volume fraction exhibit more significant interfacial damage, making pre-strain application increasingly critical. However, these conditions also impose stricter constraints on the feasible pre-strain range. By elucidating the interplay between pre-strain, material properties, and geometric factors, this study provides valuable insights for optimizing the design of carbon fiber SLIBs.
基金supported by the National Natural Science Foundation of China(Grant Nos.12072183,12472174,and 12421002).
文摘The recently reported silicon/graphite(Si/Gr)composite electrode with a layered structure is a promising approach to achieve high capacity and stable cycling of Si-based electrodes in lithium-ion batteries.However,there is still a need to clarify why particular layered structures are effective and why others are ineffective or even detrimental.In this work,an unreported mechanism dominated by the porosity evolution of electrodes is proposed for the degradation behavior of layered Si/Gr electrodes.First,the effect of layering sequence on the overall electrode performance is investigated experimentally,and the results suggest that the cycling performance of the silicon-on-graphite(SG)electrode is much superior to that of the graphite-on-silicon electrode.To explain this phenomenon,a coupled mechanical-electrochemical porous electrode model is developed,in which the porosity is affected by the silicon expansion and the local constraints.The modeling results suggest that the weaker constraint of the silicon layer in the SG electrode leads to a more insignificant decrease in porosity,and consequently,the more stable cycling performance.The findings of this work provide new insights into the structural design of Si-based electrodes.
基金supported by the National Natural Science Foundation of China(grant numbers 52305321 and 62273246)The Natural Science Foundation of Jiangsu Province(BK20230496)+3 种基金China Postdoctoral Science Foundation Funded Project(2023M732536 and 2024T170630)Jiangsu Province Excellence Postdoctoral Program(2023ZB218)The National Key R&D Program of China(2022YFB4702202)The Jiangsu Provincial Key Technology R&D Program(BE2021009-02).
文摘Micro aerial vehicles(MAVs)have flexibility and maneuverability,which can offer vast potential for applications in both civilian and military domains.Compared to Fixed-wing/Rotor-wing MAVs,Flapping Wing Micro Robots(FWMRs)have garnered widespread attention among scientists due to their superior miniaturized aerodynamic theory,reduced noise,and enhanced resistance to disturbances in complex and diverse environments.Flying insects,it not only has remarkable flapping flight ability(wings),but also takeoff and landing habitat ability(legs).If the various functions of flying insects can be imitated,efficient biomimetic FWMRs can be produced.This paper provides a review of the flight kinematics,aerodynamics,and wing structural parameters of insects.Then,the traditional wings and folding wings of insect-inspired FWMRs were compared.The research progress in takeoff and landing of FWMRs was also summarized,and the future developments and challenges for insect-inspired FWMRs were discussed.
基金supported by the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(Grant No.QYZD-SSW-SYS019)。
文摘Emergence refers to the existence or formation of collective behaviors in complex systems.Here,we develop a theoretical framework based on the eigen microstate theory to analyze the emerging phenomena and dynamic evolution of complex system.In this framework,the statistical ensemble composed of M microstates of a complex system with N agents is defined by the normalized N×M matrix A,whose columns represent microstates and order of row is consist with the time.The ensemble matrix A can be decomposed as■,where r=min(N,M),eigenvalueσIbehaves as the probability amplitude of the eigen microstate U_I so that■and U_I evolves following V_I.In a disorder complex system,there is no dominant eigenvalue and eigen microstate.When a probability amplitudeσIbecomes finite in the thermodynamic limit,there is a condensation of the eigen microstate UIin analogy to the Bose–Einstein condensation of Bose gases.This indicates the emergence of U_I and a phase transition in complex system.Our framework has been applied successfully to equilibrium threedimensional Ising model,climate system and stock markets.We anticipate that our eigen microstate method can be used to study non-equilibrium complex systems with unknown orderparameters,such as phase transitions of collective motion and tipping points in climate systems and ecosystems.
基金part of the project supported by the Shanxi Coal-bed Methane Joint Research Fund(No.2015012004)。
文摘In this paper,a model of activated carbon was established by molecular simulation and the separation performance of N2 and CH4 on activated carbon was studied.In order to evaluate the adsorption selectivity and diffusion selectivity of N2 and CH4,Grand Canonical Monte Carlo and molecular dynamic methods were used to obtain equilibrium adsorption isotherms and mean square displacements of N2 and CH4 on activated carbon with different pore sizes.Research results showed that the difference in adsorption isosteric heat of N2 and CH4 at the pore size of 0.46 nm is the largest,which is 5.759 and 7.03 kcal·mol^-1(1 cal=4.184 J),respectively.Activated carbon with pore size of 0.46 nm has the best N2 and CH4 adsorption selectivity,while its diffusion selectivity is not obvious.
基金supported by a grant from Xuzhou Municipal,China
文摘BACKGROUND:Acute liver failure(ALF) caused by viral and non-viral hepatitis is often accompanied with severe metabolic disorders,the accumulation of toxic substances and continuous release and accumulation of a large number of endogenous toxins and inflammatory mediators. The present study aimed to investigate the effects of various combined non-biological artif icial liver treatments for patients with acute liver failure(ALF) complicated by multiple organ dysfunction syndrome(MODS).METHODS:Thirty-one patients with mid- or late-stage liver failure complicated by MODS(score 4) were randomly divided into three treatment groups:plasmapheresis(PE) combined with hemoperfusion(HP) and continuous venovenous hemodiafiltration(CVVHDF),PE+CVVHDF,and HP+CVVHDF,respectively. Heart rate(HR) before and after treatment,mean arterial pressure(MAP),respiratory index(PaO2/FiO2),hepatic function,platelet count,and blood coagulation were determined.RESULTS:Signifi cant improvement was observed in HR,MAP,PaO2/FiO2,total bilirubin(TBIL) and alanine aminotransferase(ALT) levels after treatment(P<0.05). TBIL and ALT decreased more signifi cantly after treatment in the PE+CVVHDF and PE+HP+CVVHDF groups(P<0.01). Prothrombin time(PT) and albumin were signifi cantly improved only in the PE+CVVHDF and PE+HP+CVVHDF groups(P<0.05). TBIL decreased more significantly in the PE+HP+CVVHDF group than in the HP+CVVHDF and PE+CVVHDF groups(P<0.05). The survival rate of the patients was 58.1%(18/31),viral survival rate 36.4%(4/11),and non-viral survival rate 70%(14/20).CONCLUSION:Liver function was relatively improved after treatment,but PE+HP+CVVHDF was more efficient for the removal of toxic metabolites,especially bilirubin. The survival rate was signifi cantly higher in the patients with non-viral liver failure than in those with viral liver failure.
基金National Natural Science Foundation of China(Grant Nos.11874254,51802187,and 51622207)Shanghai Sailing Program,China(Grant No.18YF1408700)+3 种基金Shanghai Pujiang Program,China(Grant No.2019PJD016)Open Project of the State Key Laboratory of Advanced Special Steel,Shanghai University,China(Grant No.SKLASS2018-01)the Project of the State Key Laboratory of Advanced Special Steel,Shanghai University,China(Grant No.SKLASS2019-Z023)the Science and Technology Commission of Shanghai Municipality,China(Grant No.19DZ2270200).
文摘In anode free batteries(AFBs), the current collector acts as anode simultaneously and has large volume expansion which is generally considered as a negative effect decreasing the structural stability of a battery. Moreover, despite many studies on the fast lithium diffusion in the current collector materials of AFB such as copper and aluminum, the involved Li diffusion mechanism in these materials remains poorly understood. Through first-principles calculation and stress-assisted diffusion equations, here we study the Li diffusion mechanism in several current collectors and related alloys and clarify the effect of volume expansion on Li diffusion respectively. It is suggested that due to the lower Li migration barriers in aluminum and tin, they should be more suitable to be used as AFB anodes, compared to copper, silver, and lead. The Li diffusion facilitation in copper with a certain number of vacancies is proposed to explain why the use of copper with a thickness≤100 nm as the protective coating on the anode improves the lifetime of the batteries. We show that the volume expansion has a positive effect on Li diffusion via mechanical–electrochemical coupling. Namely, the volume expansion caused by Li diffusion will further induce stress which in turn affects the diffusion. These findings not only provide in-depth insight into the operating principle of AFBs, but also open a new route toward design of improved anode through utilizing the positive effect of mechanical–electrochemical coupling.
基金funded by the Program of Shanghai Municipal Health Commission (No.19401970400)the National Natural Science Foundation of China (No.82174130 and No.82274262)Shanghai Collaborative Innovation Center of Industrial Transformation of Hospital TCM Preparation。
文摘Background:Hypertension,a prevalent disease,is a significant risk factor for coronary heart disease.Huoxue Qianyang Qutan Recipe (HQQR),a traditional Chinese herbal remedy,has been used for treating hypertension over several years.Objective:This study assesses HQQR’s efficacy for controlling blood pressure among patients with hypertension related to blood stasis,yang hyperactivity and phlegm.Design,setting,participants and interventions:A randomized controlled trial was conducted at the Yueyang Hospital of Integrated Traditional Chinese and Western Medicine,Shanghai University of Traditional Chinese Medicine,China,from July 2020 to June 2022.Major components of HQQR were identified using thin-layer chromatography and high-performance liquid chromatography.Participants aged18–80 years,exhibiting traditional Chinese medicine syndromes of blood stasis,yang hyperactivity or phlegm,along with grades 1 or 2 hypertension,were randomly categorized into two groups.The intervention group was given HQQR granules alongside conventional hypertension treatment,while the control group was given placebo granules in addition to conventional treatment for 12 weeks.Main outcome measures:The primary outcome was clinic blood pressure,whereas secondary outcomes included metabolic indices (e.g.,homeostasis model assessment of insulin resistance[HOMA-IR],total cholesterol[TC],low-density lipoprotein cholesterol and triglyceride),target organ damage indices (left ventricular mass index and urinary albumin creatinine ratio[UACR]) and inflammation indices(interleukin-6[IL-6]and high-sensitivity C-reactive protein[hs-CRP]).Results:HQQR’s primary components were identified as salvianolic acid B,emodin and ferulic acid.Of the 216 participants (108 in each group),compared to the control,the intervention group exhibited significant improvements (P<0.001) in clinic systolic blood pressure ([136.24±7.63]vs[130.06±8.50]mmHg),clinic diastolic blood pressure ([84.34±8.72]vs[80.46±6.05]mmHg),home systolic blood pressure([131.64±8.74]vs[122.36±8.45]mmHg) and home diastolic blood pressure ([78.47±9.53]vs[71.79±6.82]mm Hg).HQQR demonstrated a reduction in ambulatory blood pressure (24-hour systolic blood pressure:[133.75±10.49]vs[132.46±8.84]mmHg and 24-hour diastolic blood pressure:[84.12±8.01]vs[82.11±7.45]mmHg) and an improvement in HOMA-IR ([4.09±1.72]vs[3.98±1.44]),TC ([4.66±1.47]vs[3.75±1.81]mmol/L) and UACR (75.94[5.12,401.12]vs 45.61[4.26,234.26]).Moreover,HQQR demonstrated a decrease in hs-CRP (1.46[0.10,10.53]vs 0.57[0.12,3.99]mg/L) and IL-6 (6.69[2.00,29.74]vs 5.27[2.00,9.73]pg/mL),with no reported side effects (P<0.001).Conclusion:This study highlights the therapeutic potential of HQQR use in ameliorating blood pressure,glycolipid metabolism,and inflammation in patients with hypertension.
基金supported by the National Natural Science Foundation of China(NSFC, Nos. 21771021 and 21473013)the National Basic Research Program of China(973 Program, No. 2014CB932103)Beijing Municipal Natural Science Foundation (No. 2152016)
文摘Luminescent cocrystals have been received much attention in fluorescence imaging and sensor application. In this work, we report that the high-quality chiral luminescent cocrystal can be obtained through a molecular self-assembly process of 2,20-binaphthol and 2-（3-pyridyl）-1 H-benzimidazole. The assembly modes and stacking fashions of as-obtained cocrystal were determined by single crystal X-ray diffractometer. The structure and optical properties of the cocrystals were characterized by fluorescence emission, fluorescence decay, Raman and circular dichroism spectra. The results show that both the pristine co-assembled units（R-BINOL and S-BINOL） give rise to the R conformation within the final cocrystal, suggesting that the formation of cocrystal can be an effective way to achieve R/S-isomeric transformation of 2,20-binaphthol. It is also expected that the co-crystallization approach has much flexibility and potential applications for the design and selective formation of chiral luminescent materials.
基金Supported by the National Natural Science Foundation of China(21176028 and21506011)the National Science Fund for Distinguished Young Scholars of China(21425624)Doctoral Fund of Ministry of Education of China(20121101110050)
文摘Glycyrrhetic acid 3-O-mono-β-D-glucuronide （GAMG）, the major functional ingredient in licorice, has widespread applications in food, pharmacy and cosmetics industry. The production of GAMG through Penicillium purpurogenum Li-3 cultivation was for the first time performed through both batch and fed-batch processes in bioreactors. In batch process, under optimal conditions （pH 5.0, temperature 32℃, agitation speed 100 r. rain 1）, 3.55 g. L^-1 GAMG was obtained in a 2.5 L fermentor. To further enhance GAMG production, a fine fed-batch process was developed by using pH and DO as feedback parameters. Starting from 48 h, 100 m190 g-L 1 substrate Glycyrrhizin （GL） was fed each time when pH increased to above 5.0 and DO was increased to above 80%. This strategy can significantly enhance GAMG production： the achieved GL conversion was 95.34% with GAMG yield of 95.15%, and GAMG concentration was 16.62 g. L^-1 which was 5 times higher than that of batch. Then, a two-step separation strat- egy was established to separate GAMG from fermentation broth by crude extraction of 15 ml column packed with D10I resin followed by fine purification with preparative C18 chromatography. The obtained GAMG purity was 95.79%. This study provides a new insight into the industrial bioprocess of high-level GAMG production.
基金Project supported by the National Natural Science Foundation of China(Nos.12072183 and11872236)the Key Research Project of Zhejiang Laboratory(No.2021PE0AC02)。
文摘Electric vehicles(EVs)have garnered significant attention as a vital driver of economic growth and environmental sustainability.Nevertheless,ensuring the safety of high-energy batteries is now a top priority that cannot be overlooked during large-scale applications.This paper proposes an innovative active protection and cooling integrated battery module using smart materials,magneto-sensitive shear thickening fluid(MSTF),which is specifically designed to address safety threats posed by lithium-ion batteries(LIBs)exposed to harsh mechanical and environmental conditions.The theoretical framework introduces a novel approach for harnessing the smoothed-particle hydrodynamics(SPH)methodology that incorporates the intricate interplay of non-Newtonian fluid behavior,capturing the fluid-structure coupling inherent to the MSTF.This approach is further advanced by adopting an enhanced Herschel-Bulkley(H-B)model to encapsulate the intricate rheology of the MSTF under the influence of the magnetorheological effect(MRE)and shear thickening(ST)behavior.Numerical simulation results show that in the case of cooling,the MSTF is an effective cooling medium for rapidly reducing the temperature.In terms of mechanical abuse,the MSTF solidifies through actively applying the magnetic field during mechanical compression and impact within the battery module,resulting in 66%and 61.7%reductions in the maximum stress within the battery jellyroll,and 31.1%and 23%reductions in the reaction force,respectively.This mechanism effectively lowers the risk of short-circuit failure.The groundbreaking concepts unveiled in this paper for active protection battery modules are anticipated to be a valuable technological breakthrough in the areas of EV safety and lightweight/integrated design.
基金Supported by the Key-Area Research and Development Program of Guangdong Province,China (Grant No. 2019B030330001)the National Natural Science Foundation of China (Grant Nos. 12025509 and 11874434)+2 种基金the Science and Technology Program of Guangzhou,China (Grant Nos. 201904020024 and 201804010497)the Natural Science Foundation of Guangdong Province,China(Grant No. 2018A030313988)the Fundamental Research Funds for the Central Universities (Grant No. 2021qntd28)
文摘We report the production of ^(87)Rb Bose–Einstein condensate in an asymmetric crossed optical dipole trap(ACODT)without the need of an additional dimple laser.In our experiment,the ACODT is formed by two laser beams with different radii to achieve efficient capture and rapid evaporation of laser cooled atoms.Compared to the cooling procedure in a magnetic trap,the atoms are firstly laser cooled and then directly loaded into an ACODT without the pre-evaporative cooling process.In order to determine the optimal parameters for evaporation cooling,we optimize the power ratio of the two beams and the evaporation time to maximize the final atom number left in the ACODT.By loading about 6×10^(5) laser cooled atoms in the ACODT,we obtain a pure Bose–Einstein condensate with about 1.4×10^(4) atoms after 19 s evaporation.Additionally,we demonstrate that the fringe-type noises in optical density distributions can be reduced via principal component analysis,which correspondingly improves the reliability of temperature measurement.
基金Project supported by the National Natural Science Foundation of China(Nos.12072183,11872236,12172205)the Key Research Project of Zhejiang Laboratory of China(No.2021PE0AC02)。
文摘The interfacial debonding between the active layer and the current collector has been recognized as a critical mechanism for battery fading,and thus has attracted great efforts focused on the related analyses.However,much still remains to be studied regarding practical methods for suppressing electrode debonding,especially from the perspective of mechanics.In this paper,a pre-strain strategy of current collectors to alleviate electrode debonding is proposed.An analytical model for a symmetric electrode with a deformable and limited-thickness current collector is developed to analyze the debonding behavior involving both a pre-strain of the current collector and an eigen-strain of the active layers.The results reveal that the well-designed pre-strain can significantly delay the debonding onset(by up to 100%)and considerably reduce the debonding size.The critical values of the pre-strain are identified,and the pre-strain design principles are also provided.Based on these findings,this work sheds light on the mechanical design to suppress electrode degradation.
基金supported by the National Natural Science Foundation of China (Grant Nos.12072183,11872236 and 12172205)the Key Research Project of Zhejiang Laboratory (No.2021PE0AC02).
文摘The variation of the effective modulus of silicon composite electrodes,which is a fundamental feature to analyze the coupled mechanical–electrochemical behavior of Si-based electrodes in high-capacity lithium-ion batteries,remains qualitatively controversial.To clarify the contradictory experimental results,numerical modeling of a representative volume element with silicon particles,carbon-binder domains(CBDs),and pores has been performed for the lithiation process.The key parameters for modulus variation were identified and evaluated.A mesostructure change is proposed to be a crucial mechanism that affects the modulus variation,and silicon softening is another key mechanism.Silicon softening and the decreasing CBD volume fraction collectively result in a decrease in the effective modulus of the composite,whereas an increase in the silicon volume fraction along with a decrease in porosity has the opposite effect.The findings of this work provide an in-depth and fundamental understanding of the mechanical properties of silicon composite electrodes.
基金the National Natural Science Foundation of China(Grant Nos.12072236,11872276,and11802086)the Postdoctoral Research Project of Henan Province,China(Grant No.19030095)the Science and Technology Development Program of Henan Province,China(Grant No.212102210543)。
文摘Seizures are caused by increased neuronal firing activity resulting from reduced inhibitory effect and enhancement of inhibitory modulation to suppress this activity is used as a therapeutic tool.However,recent experiments have shown a counterintuitive phenomenon that inhibitory modulation does not suppress but elicit post-inhibitory rebound(PIR)spike along with seizure to challenge the therapeutic tool.The nonlinear mechanism to avoid the PIR spike can present theoretical guidance to seizure treatment.This paper focuses on identifying credible bifurcations that underlie PIR spike by modulating multiple parameters in multiple theoretical models.The study identifies a codimension-2 bifurcation called saddle-node homoclinic orbit(SNHOB),which is an intersection between saddle node bifurcation on invariant cycle(SNIC)and other two bifurcations.PIR spike cannot be evoked for the SNIC far from the SNHOBbut induced for the SNIC close to the SNHOB,which extends the bifurcation condition for PIR spike from the well-known Hopf to SNIC.Especially,in a thalamic neuron model,increases of conductance of T-type Ca^(2+)(TC a)channel induce SNIC bifurcation approaching to the SNHOB to elicit PIR spikes,closely matching experimental results of the absence seizure or Parkinson diseases.Such results imply that,when inhibition is employed to relieve absence seizure and Parkinson diseases related to PIR spike,modulating SNIC to get far from the SNHOBto avoid PIR spike is the principle.The study also addresses the complex roles of TCacurrent and comprehensive relationships between PIR spike and nonlinear conceptions such as bifurcation types and shapes of threshold curve.
基金the National Key R&D Program of China(2016YFA0400800)the National Natural Science Foundation of China(Grant Nos.U1838201,U1838202,U1838101 and U1938109)the Insight-HXMT mission,a project funded by China National Space Administration(CNSA)and the Chinese Academy of Sciences(CAS)。
文摘The LE is the low energy telescope that is carried on Insight-HXMT.It uses swept charge devices(SCDs)to detect soft X-ray photons.LE’s time response is caused by the structure of the SCDs.With theoretical analysis and Monte Carlo simulations we discuss the influence of LE time response(LTR)on the timing analysis from three aspects:the power spectral density,the pulse profile and the time lag.After the LTR,the value of power spectral density monotonously decreases with the increasing frequency.The power spectral density of a sinusoidal signal reduces by a half at frequency 536 Hz.The corresponding frequency for quasi-periodic oscillation(QPO)signals is 458 Hz.The root mean square(RMS)of QPOs holds a similar behaviour.After the LTR,the centroid frequency and full width at half maxima(FWHM)of QPOs signals do not change.The LTR reduces the RMS of pulse profiles and shifts the pulse phase.In the time domain,the LTR only reduces the peak value of the cross-correlation function while it does not change the peak position;thus it will not affect the result of the time lag.When considering the time lag obtained from two instruments and one among them is LE,a 1.18 ms lag is expected caused by the LTR.The time lag calculated in the frequency domain is the same as that in the time domain.
基金Supported by the National Natural Science Foundation of China(Grant Nos.1162618811671322+2 种基金11501451)the Natural Science Foundation of Gansu Province(Grant No.1606RJYA232)the Young Teachers’ Scientific Research Capability Upgrading Project of Northwest Normal University(Grant No.NWNU-LKQN-15-16)
文摘In this paper,the authors obtain the existence of one-signed periodic solutions of the first-order functional difference equation ？u（n） = a（n）u（n）-λb（n）f（u（n-τ（n）））,n ∈ Z by using global bifurcation techniques,where a,b：Z → [0,∞） are T-periodic functions with ∑T n=1 a（n） 〉 0,∑T n=1 b（n） 〉 0;τ：Z → Z is T-periodic function,λ 〉 0 is a parameter;f ∈ C（R,R） and there exist two constants s2 〈 0 〈 s1 such that f（s2） = f（0） = f（s1） = 0,f（s） 〉 0 for s ∈（0,s1） ∪（s1,∞）,and f（s） 〈 0 for s ∈（-∞,s2） ∪（s2,0）.
基金partially supported by the National Natural Science Foundation of China(62271485)the SDHS Science and Technology Project(HS2023B044)
文摘Imputation of missing data has long been an important topic and an essential application for intelligent transportation systems(ITS)in the real world.As a state-of-the-art generative model,the diffusion model has proven highly successful in image generation,speech generation,time series modelling etc.and now opens a new avenue for traffic data imputation.In this paper,we propose a conditional diffusion model,called the implicit-explicit diffusion model,for traffic data imputation.This model exploits both the implicit and explicit feature of the data simultaneously.More specifically,we design two types of feature extraction modules,one to capture the implicit dependencies hidden in the raw data at multiple time scales and the other to obtain the long-term temporal dependencies of the time series.This approach not only inherits the advantages of the diffusion model for estimating missing data,but also takes into account the multiscale correlation inherent in traffic data.To illustrate the performance of the model,extensive experiments are conducted on three real-world time series datasets using different missing rates.The experimental results demonstrate that the model improves imputation accuracy and generalization capability.
