The phase equilibria relationship of the system RbCl-PEG6000-H2O were investigated at temperatures of 288.2,298.2,and 308.2 K,the compositions of solid-liquid equilibria(SLE)and liquid-liquid equilibria(LLE)were deter...The phase equilibria relationship of the system RbCl-PEG6000-H2O were investigated at temperatures of 288.2,298.2,and 308.2 K,the compositions of solid-liquid equilibria(SLE)and liquid-liquid equilibria(LLE)were determined.The complete phase diagrams,binodal curve diagrams,and tie-line diagrams were all plotted.Results show that both solid-liquid equilibria and liquid-liquid equilibria relationships at each studied temperature.The complete phase diagrams at 288.2 K,298.2 K and 308.2 K consist of six phase regions:unsaturated liquid region(L),two saturated solutions with one solid phase of RbCl(L_S),one saturated liquid phase with two solid phases of PEG6000 and RbCl(2S+L),an aqueous two-phase region(2L),and a region with two liquids and one solid phase of RbCl(2L_S).With the increase in temperature,the layering ability of the aqueous two-phase system increases,and both regions(2L)and(2L_S)increase.The binodal curves were fitted using the nonlinear equations proposed by Mistry,Hu,and Jayapal.Additionally,the tie-line data were correlated with the Othmer-Tobias,Bancroft,Hand,and Bachman equations.The liquid-liquid equilibria at 288.2 K,298.2 K and 308.2 K were calculated using the NRTL model.The findings confirm that the experimental and calculated values are in close agreement,demonstrating the model’s effectiveness in representing the system’s behavior.展开更多
Sandy cobble soil exhibits pronounced heterogeneity.The assessment of the uncertainty surrounding its properties is crucial for the analysis of settlement characteristics resulting from volume loss during shield tunne...Sandy cobble soil exhibits pronounced heterogeneity.The assessment of the uncertainty surrounding its properties is crucial for the analysis of settlement characteristics resulting from volume loss during shield tunnelling.In this study,a series of probabilistic analyses of surface and subsurface settlements was conducted considering the spatial variability of the friction angle and reference stiffness modulus,under different volumetric block proportions(Pv)and tunnel volume loss rates(ηt).The non-intrusive random finite difference method was used to investigate the probabilistic characteristics of maximum surface settlement,width of subsurface settlement trough,maximum subsurface settlement,and subsurface soil volume loss rate through Monte Carlo simulations.Additionally,a comparison between stochastic and deterministic analysis results is presented to underscore the significance of probabilistic analysis.Parametric analyses were subsequently conducted to investigate the impacts of the key input parameters in random fields on the settlement characteristics.The results indicate that scenarios with higher Pv or greaterηt result in a higher dispersion of stochastic analysis results.Neglecting the spatial variability of soil properties and relying solely on the mean values of material parameters for deterministic analysis may result in an underestimation of surface and subsurface settlements.From a probabilistic perspective,deterministic analysis alone may prove inadequate in accurately capturing the volumetric deformation mode of the soil above the tunnel crown,potentially affecting the prediction of subsurface settlement.展开更多
This study investigates the dynamical behavior of two parallel fluid-conveying pipes by developing a non-planar dynamical model of the two pipes coupled with an intermediate spring. A systematic analysis is conducted ...This study investigates the dynamical behavior of two parallel fluid-conveying pipes by developing a non-planar dynamical model of the two pipes coupled with an intermediate spring. A systematic analysis is conducted to evaluate the effects of spring parameters on the non-planar vibration characteristics and buckling behaviors of the coupled system. The nonlinear governing equations are derived with Hamilton's principle,subsequently discretized through Galerkin's method, and finally numerically solved by the Runge-Kutta algorithm. Based on the linearized equations, an eigenvalue analysis is performed to obtain the coupled frequencies, modal shapes, and critical flow velocities for buckling instability. Quantitative assessments further elucidate the effects of the spring position and stiffness coefficient on the coupled frequencies and critical flow velocities.Nonlinear dynamic analyses reveal the evolution of buckling patterns and bifurcation behaviors between the lateral displacements of the two pipes and the flow velocity. Numerical results indicate that the intermediate spring increases the susceptibility to buckling instability in the out-of-plane direction compared with the in-plane direction. Furthermore, synchronized lateral displacements emerge in both pipes when the flow velocity of one pipe exceeds the critical threshold. This work is expected to provide a theoretical foundation for the stability assessment and vibration analysis in coupled fluid-conveying pipe systems.展开更多
Sodium-ion hybrid capacitors(SICs),which combine the high energy density of batteries with the high power density and long cycle life of capacitors,are considered promising next-generation energy storage devices.Ensur...Sodium-ion hybrid capacitors(SICs),which combine the high energy density of batteries with the high power density and long cycle life of capacitors,are considered promising next-generation energy storage devices.Ensuring the performance of SICs in low-temperature environments is crucial for applications in high-altitude cold regions,where the desolvation process of Na+and the transport process in the solid electrolyte interphase(SEI)are determinant.In this paper,we proposed a multi-ether modulation strategy to construct a solvation sheath with multi-ether participation by modulating the coordination of Na+and solvents.This unique solvation sheath not only reduces the desolvation energy barrier of Na+,but more importantly forms a Na_(2)O-rich inorganic SEI and enhances the ionic dynamics of Na+.Benefiting from the excellent solvation structure design,SICs prepared with this electrolyte can achieve energy density of up to 178 Wh·kg^(-1) and ultra-high power density of 42390 W·kg^(-1) at room temperature.Notably,this SIC delivers record-high energy densities of 149 Wh·kg^(-1) and 119 Wh·kg^(-1) as well as power densities of up to 25200 W·kg^(-1) and 24591 W·kg^(-1) at−20℃ and−40℃,respectively.This work provides new ideas for the development of high-performance SICs for low-temperature operating environments.展开更多
Cold-surge events can lead to temperature drops and strong winds,which then leads to upper-ocean cooling and deepening of the mixed-layer depth,as illustrated in previous studies.In this study,based on the temperature...Cold-surge events can lead to temperature drops and strong winds,which then leads to upper-ocean cooling and deepening of the mixed-layer depth,as illustrated in previous studies.In this study,based on the temperature drop of Shanwei meteorological station,two extreme cold surges and five weak cold invasions in the South China Sea are simulated using an ocean-atmosphere coupled model to investigate their different impacts on the upper-ocean temperature.The diffusion term contributes to the difference in temperature tendency of the upper 20 m,while the advection term contributes to the positive difference from 20 to 80 m of the offshore region and negative difference from 80 to 160 m.In addition,the significant differences are attributed primarily to the influence of the upper-ocean temperature gradient,which subsequently impacts the advection term and results in notable differences in temperature tendency at depths from 80 to 160 m.展开更多
Bioremediation became a promising technology to resolve arsenic(As)contamination in aquatic environment.Since monoculture such as microalgae or bacteria was sensitive to environmental disturbance and vulnerable to con...Bioremediation became a promising technology to resolve arsenic(As)contamination in aquatic environment.Since monoculture such as microalgae or bacteria was sensitive to environmental disturbance and vulnerable to contamination,green microalgae Chlorella vulgaris and arsenite(As(Ⅲ))-oxidizing bacteria Pseudomonas sp.SMS11 were co-cultured to construct algal-bacterial consortia in the current study.The effects of algae-bacteria(A:B)ratio and exposure As(Ⅲ)concentration on algal growth,As speciation and metabolomic profile were investigated.Algal growth arrested when treated with 100 mg/L As(Ⅲ)without the co-cultured bacteria.By contrast,co-cultured with strain SMS11 significantly enhanced As tolerance in C.vulgaris especially with A:B ratio of 1:10.All the As(Ⅲ)in culture media of the consortia were oxidized into As(Ⅴ)on day 7.Methylation of As was observed on day 14.Over 1% and 0.5% of total As were converted into dimethylarsinic acid(DMA)after 21days cultivation when the initial concentrations of As(Ⅲ)were 1 and 10 mg/L,respectively.Metabolomic analysis was further performed to reveal the response of consortia metabolites to external As(Ⅲ).The enriched metabolomic pathways were associated with carbohydrate,amino acid and energy metabolisms.Tricarboxylic acid cycle and glyoxylate and dicarboxylate metabolism were upregulated under As stress due to their biological functions on alleviating oxidative stress and protecting cells.Both carbohydrate and amino acid metabolisms provided precursors and potential substrates for energy production and cell protection under abiotic stress.Alterations of the pathways relevant to carbohydrate or amino acid metabolism were triggered by energy requirement.展开更多
Objective:To provide real-world evidence for the application of first-line dacomitinib treatment for epidermal growth factor receptor(EGFR)21L858R mutant non-small cell lung cancer(NSCLC)patients in China and to explo...Objective:To provide real-world evidence for the application of first-line dacomitinib treatment for epidermal growth factor receptor(EGFR)21L858R mutant non-small cell lung cancer(NSCLC)patients in China and to explore the factors influencing the efficacy and safety.Methods:A longitudinal,consecutive case-series,multicenter study with mixed prospective and retrospective data was conducted.The primary endpoint was progression-free survival(PFS),and the secondary endpoints included duration of treatment(DOT),overall survival(OS),objective response rate(ORR),disease control rate(DCR)and safety.Results:A total of 155 EGFR 21L858R mutant patients treated with first-line dacomitinib were included.The median follow-up time for these patients was 20.4 months.Among 134 patients with evaluable lesions,the ORR was 70.9%and the DCR was 96.3%.The median PFS was 16.3[95%confidence interval(95%CI),13.7−18.9]months.Multivariate Cox regression analysis suggested that the baseline brain metastasis(BM)status[with vs.without BM:hazard ratio(HR),1.331;95%CI,0.720−2.458;P=0.361]and initial doses(45 mg vs.30 mg:HR,0.837;95%CI,0.427−1.641;P=0.604)did not significantly affect the median PFS.The median DOT was 21.0(95%CI,17.5−24.6)months and the median OS was not reached.Genetic tests were performed in 64 patients after progression,among whom 29(45.3%)patients developed the EGFR 20T790M mutation.In addition,among the 46 patients who discontinued dacomitinib treatment after progression,31(67.4%)patients received subsequent third-generation EGFR-tyrosine kinase inhibitors.The most common grade 3−4 adverse events were rash(10.4%),diarrhea(9.1%),stomatitis(7.1%)and paronychia(4.5%).The incidence of grade 3−4 rash was significantly higher in the 45 mg group than that in the 30 mg group(21.9%vs.7.5%,P=0.042).Conclusions:First-line dacomitinib treatment demonstrated promising efficacy and tolerable adverse events among EGFR 21L858R mutant NSCLC patients in China.展开更多
Crystallineγ-Ga_(2)O_(3)@rGO core-shell nanostructures are synthesized in gram scale,which are accomplished by a facile sonochemical strategy under ambient condition.They are composed of uniformγ-Ga_(2)O_(3)nanosphe...Crystallineγ-Ga_(2)O_(3)@rGO core-shell nanostructures are synthesized in gram scale,which are accomplished by a facile sonochemical strategy under ambient condition.They are composed of uniformγ-Ga_(2)O_(3)nanospheres encapsulated by reduced graphene oxide(rGO)nanolayers,and their formation is mainly attributed to the existed opposite zeta potential between the Ga_(2)O_(3)and rGO.The as-constructed lithium-ion batteries(LIBs)based on as-fabricatedγ-Ga_(2)O_(3)@rGO nanostructures deliver an initial discharge capacity of 1000 mAh g^(-1)at 100 mA g^(-1)and reversible capacity of 600 mAh g^(-1)under 500 mA g^(-1)after 1000 cycles,respectively,which are remarkably higher than those of pristineγ-Ga_(2)O_(3)with a much reduced lifetime of 100 cycles and much lower capacity.Ex situ XRD and XPS analyses demonstrate that the reversible LIBs storage is dominant by a conversion reaction and alloying mechanism,where the discharged product of liquid metal Ga exhibits self-healing ability,thus preventing the destroy of electrodes.Additionally,the rGO shell could act robustly as conductive network of the electrode for significantly improved conductivity,endowing the efficient Li storage behaviors.This work might provide some insight on mass production of advanced electrode materials under mild condition for energy storage and conversion applications.展开更多
Due to the novel applications of flexible pipes conveying fluid in the field of soft robotics and biomedicine,the investigations on the mechanical responses of the pipes have attracted considerable attention.The fluid...Due to the novel applications of flexible pipes conveying fluid in the field of soft robotics and biomedicine,the investigations on the mechanical responses of the pipes have attracted considerable attention.The fluid-structure interaction(FSI)between the pipe with a curved shape and the time-varying internal fluid flow brings a great challenge to the revelation of the dynamical behaviors of flexible pipes,especially when the pipe is highly flexible and usually undergoes large deformations.In this work,the geometrically exact model(GEM)for a curved cantilevered pipe conveying pulsating fluid is developed based on the extended Hamilton's principle.The stability of the curved pipe with three different subtended angles is examined with the consideration of steady fluid flow.Specific attention is concentrated on the large-deformation resonance of circular pipes conveying pulsating fluid,which is often encountered in practical engineering.By constructing bifurcation diagrams,oscillating shapes,phase portraits,time traces,and Poincarémaps,the dynamic responses of the curved pipe under various system parameters are revealed.The mean flow velocity of the pulsating fluid is chosen to be either subcritical or supercritical.The numerical results show that the curved pipe conveying pulsating fluid can exhibit rich dynamical behaviors,including periodic and quasi-periodic motions.It is also found that the preferred instability type of a cantilevered curved pipe conveying steady fluid is mainly in the flutter of the second mode.For a moderate value of the mass ratio,however,a third-mode flutter may occur,which is quite different from that of a straight pipe system.展开更多
Antimicrobial photodynamic therapy(aPDT)has been considered a noninvasive and effective modality against the bacterial infection of peri‑implantitis,especially the aPDT triggered by near-infrared(NIR)light due to the ...Antimicrobial photodynamic therapy(aPDT)has been considered a noninvasive and effective modality against the bacterial infection of peri‑implantitis,especially the aPDT triggered by near-infrared(NIR)light due to the large penetration depth in tissue.However,the complexity of hypoxia microenvironments and the distance of aPDT sterilization still pose challenges before realizing the aPDT clinical application.Due to the long lifespan and transmission distance of therapeutic gas molecules,we design a multi-functional gas generator that combines aPDT as well as O_(2) and CO gas release function,which can solve the problem of hypoxia(O_(2))in PDT and the problem of inflammation regulation(CO)in the distal part of peri‑implant inflammation under near-infrared(NIR)irradiation.In the composite nanoplatform that spin-coated on the surface of titanium implants,up-conversion nanoparticles(UCNPs)were involved in converting the NIR to visible,which further excites the partially oxidized stannic sulfide(SnS_(2)),realizing the therapeutic gas release.Indocyanine green(ICG)was further integrated to enhance the aPDT performance(Ti-U@SnS_(2)/I).Therefore,reactive oxygen species(ROS),CO,and O_(2) can be controllably administered via a composite nano-platform mediated by a single NIR light(808 nm).This implant surface modification strategy could achieve great self-enhancement antibacterial effectiveness and regulate the lingering questions,such as relieving the anoxic microenvironment and reaching deep infection sites,providing a viable antibiotic-free technique to combat peri‑implantitis.展开更多
In the present work,the laminar plasma surface hardening method is employed to enhance the service life of metal components fabricated from 65 Mn steel.The mechanical and wear behaviors of the laminar plasma surface h...In the present work,the laminar plasma surface hardening method is employed to enhance the service life of metal components fabricated from 65 Mn steel.The mechanical and wear behaviors of the laminar plasma surface hardened 65 Mn steel were analyzed.The martensite transition transformation of the temperature of the laminar plasma-hardened 65 ferrite Mn steel was determined by a thermal-solid coupling model.Based on the orthogonal experimental results,the optimal hardening parameters were confirmed.The scanning velocity,quenching distance and arc current are 130 mm/min,50 mm and 120 A,respectively.The pearlites and ferrites are transformed into martensites in the hardened zone,while the ratio of martensite in the heataffected zone decreases with the increase in the hardening depth.Compared to the untreated 65Mn steel,the average hardness increases from 220 HV_(0.2)to 920 HV_(0.2)in the hardened zone and the corresponding absorbed power increases from 118.7 J to 175.5 J.At the same time,the average coefficient of friction(COF)decreases from 0.763 to 0.546,and the wear rate decreases from 5.39×10^(-6)mm^(3)/(N·m)to 2.95×10^(-6)mm^(3)/(N·m),indicating that the wear resistance of 65Mn steel could be significantly improved by using laminar surface hardening.With the same hardening parameters,the depth and width of the hardened zone predicted by the thermal-solid coupling model are 1.85 mm and 11.20 mm,respectively,which are in accordance with the experimental results;depth is 1.83 mm and width is 11.15 mm.In addition,the predicted hardness distributions of the simulation model are in accordance with the experimental results.These results indicate that the simulation model could effectively predict the microstructure characteristics of 65 Mn steel.展开更多
Impact deformation behaviors of CT20 alloy with lamellar microstructure(LM),equiaxed microstructure(EM)and bimodal microstructure(BM)at room temperature were systematically investigated in this study.The experimental ...Impact deformation behaviors of CT20 alloy with lamellar microstructure(LM),equiaxed microstructure(EM)and bimodal microstructure(BM)at room temperature were systematically investigated in this study.The experimental results indicated the excellent mechanical properties of CT20 alloy with BM un-der dynamic load.The impact toughness of BM specimen(∼118 J/cm^(2))is∼17.5%higher than that of LM specimen and∼33.8%higher than that of EM specimen.The impact energy of EM specimen is the lowest due to the relatively simple equiaxed microstructure.LM specimen can absorb the highest crack initia-tion energy due to the best twinning ability.The highest impact toughness of BM specimen is induced by multi-factor coupling during impact deformation.Finer initial equivalent grain size,smaller lamellar thickness,lamellar induces twinning,finer twins,crack propagation path,and interaction between twins andβlamellar are all factors affecting impact toughness.展开更多
The nonlinear forced vibrations of a cantilevered pipe conveying fluid under base excitations are explored by means of the full nonlinear equation of motion, and the fourth- order Runge-Kutta integration algorithm is ...The nonlinear forced vibrations of a cantilevered pipe conveying fluid under base excitations are explored by means of the full nonlinear equation of motion, and the fourth- order Runge-Kutta integration algorithm is used as a numerical tool to solve the discretized equations. The self-excited vibration is briefly discussed first, focusing on the effect of flow velocity on the stability and post-flutter dynamical behavior of the pipe system with parameters close to those in previous experiments. Then, the nonlinear forced vibrations are examined using several concrete examples by means of frequency response diagrams and phase-plane plots. It shows that, at low flow velocity, the resonant amplitude near the first-mode natural frequency is larger than its counterpart near the second-mode natural frequency. The second-mode frequency response curve clearly displays a softening-type behavior with hysteresis phenomenon, while the first-mode frequency response curve almost maintains its neutrality. At moderate flow velocity, interestingly, the first-mode resonance response diminishes and the hysteresis phenomenon of the second-mode response disappears. At high flow velocity beyond the flutter threshold, the frequency response curve would exhibit a quenching-like behavior. When the excitation frequency is increased through the quenching point, the response of the pipe may shift from quasiperiodic to periodic. The results obtained in the present work highlight the dramatic influence of internal fluid flow on the nonlinear forced vibrations of slender Pipes.展开更多
The linkage between Qi and mitochondria was investigated by exploring the effect of Traditional Chinese Medicine (TCM) Qi-invigorating herbs on mitochondrial function at the biochemical and molecular levels. Three Chi...The linkage between Qi and mitochondria was investigated by exploring the effect of Traditional Chinese Medicine (TCM) Qi-invigorating herbs on mitochondrial function at the biochemical and molecular levels. Three Chinese herbs (<i></span><i><span style="font-family:Verdana;">Astragali radix</span></i><span style="font-family:Verdana;">,</span><i><span style="font-family:Verdana;"> Herba cistanche</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Panax ginseng</span></i><span style="font-family:Verdana;"></i>) were used to treat cultured mouse kidney cells and the generation of adenosine triphosphate (ATP) was measured. The Qi-invigorating herb, <i></span><i><span style="font-family:Verdana;">Astragali radix</span></i><span style="font-family:Verdana;"></i>, was selected for further </span></span><span style="font-family:""><span style="font-family:Verdana;">study using additional biological and molecular parameters, including ATP, reactive oxygen species (ROS), mitochondrial membrane potential (MMP),</span><span><span style="font-family:Verdana;"> mtDNA copies, superoxide dismutase (SOD), glutathione (GSH), cell growth, cell viability and transcriptomes. We also chose two concentrations of <i></span><i><span style="font-family:Verdana;">Astragali radix</span></i><span style="font-family:Verdana;"></i> to study the hormetic effect. The results indicated that: 1) Qi-invigorating herbs have significant effects on the function of mitochondria, with ATP production and the antioxidant capacity being significantly enhanced, and ROS le</span></span><span style="font-family:Verdana;">vels being reduced, allowing for a more optimal oxidation environment. The effect of the herbs followed a hormetic curve with a stimulating effect at lower</span><span> </span><span style="font-family:Verdana;">doses but an inhibiting effect at high doses;2) The growth of the cells was not</span><span> </span><span style="font-family:Verdana;">affected despite numerous biochemical changes associated with mitochondrial</span><span> </span><span style="font-family:Verdana;">function, indicating the powerful ability of mitochondria to maintain cellular homeostasis;3) The up-regulation of NOCT gene, related to nicotinamide adenine dinucleotide (NADH) synthesis, offers a molecular basis for the ATP-promoting effect of the Qi-invigorating herbs. This work provides additional insight into the efficacy of TCM herbs from a western perspective.展开更多
<div style="text-align:justify;"> Titanium alloy materials are widely used in the marine and aviation fields due to their excellent properties. The submersible sailing on the water surface is faster th...<div style="text-align:justify;"> Titanium alloy materials are widely used in the marine and aviation fields due to their excellent properties. The submersible sailing on the water surface is faster than underwater diving, so once an accident occurs, the consequences are unimaginable. Based on the failure criterion of the J-K model, this paper uses finite element simulation software to study the impact of impact velocity and impact angle on the collision response of a titanium alloy cylindrical pressure shell, providing a reference for the deep sea titanium alloy pressure shell. </div>展开更多
<i><span style="font-family:Verdana;">Astragali Radix </span></i><span style="font-family:Verdana;">(AR), the dried root of legumes, belongs to the Qi-invigorating<...<i><span style="font-family:Verdana;">Astragali Radix </span></i><span style="font-family:Verdana;">(AR), the dried root of legumes, belongs to the Qi-invigorating</span><span style="font-family:""> <span style="font-family:Verdana;">herbs in traditional Chinese medicine and plays an important role in the</span><span style="font-family:Verdana;"> treatment of many diseases. In order to understand the mechanism of action of AR extract. We used AR extract to treat M-1, mouse kidney cells, and used transcriptome sequencing technology to detect the genomic transcription level of the cells under the action of AR at different concentrations and times. The results showed that after a low concentration of AR treatments on the cells, the expression of genes related to cell growth and cellular immune response changed significantly, among which multiple genes are related to mitochondrial function, while high concentrations of AR affected the expression of histones and disease-related genes. It showed that the low concentration of AR extract can achieve the effect of invigorating Qi by regulating the function of mitochondria. In addition, several important genes and pathways were identified as potential targets of AR activation. The research not only clarified the main molecular biological mechanism of AR invigorating Qi, but also provided experimental basis and cellular physiology reference for the further clinical application of AR.展开更多
基金supported by the National Natural Science Foundation of China(U1507111).
文摘The phase equilibria relationship of the system RbCl-PEG6000-H2O were investigated at temperatures of 288.2,298.2,and 308.2 K,the compositions of solid-liquid equilibria(SLE)and liquid-liquid equilibria(LLE)were determined.The complete phase diagrams,binodal curve diagrams,and tie-line diagrams were all plotted.Results show that both solid-liquid equilibria and liquid-liquid equilibria relationships at each studied temperature.The complete phase diagrams at 288.2 K,298.2 K and 308.2 K consist of six phase regions:unsaturated liquid region(L),two saturated solutions with one solid phase of RbCl(L_S),one saturated liquid phase with two solid phases of PEG6000 and RbCl(2S+L),an aqueous two-phase region(2L),and a region with two liquids and one solid phase of RbCl(2L_S).With the increase in temperature,the layering ability of the aqueous two-phase system increases,and both regions(2L)and(2L_S)increase.The binodal curves were fitted using the nonlinear equations proposed by Mistry,Hu,and Jayapal.Additionally,the tie-line data were correlated with the Othmer-Tobias,Bancroft,Hand,and Bachman equations.The liquid-liquid equilibria at 288.2 K,298.2 K and 308.2 K were calculated using the NRTL model.The findings confirm that the experimental and calculated values are in close agreement,demonstrating the model’s effectiveness in representing the system’s behavior.
基金supported by the Natural Science Foundation of Beijing Municipality(No.8222004),Chinathe National Natural Science Foundation of China(No.51978019)+3 种基金the Natural Science Foundation of Henan Province(No.252300420445),Chinathe Doctoral Research Initiation Fund of Henan University of Science and Technology(No.4007/13480062),Chinathe Henan Postdoctoral Foundation(No.13554005),Chinathe Joint Fund of Science and Technology R&D Program of Henan Province(No.232103810082),China。
文摘Sandy cobble soil exhibits pronounced heterogeneity.The assessment of the uncertainty surrounding its properties is crucial for the analysis of settlement characteristics resulting from volume loss during shield tunnelling.In this study,a series of probabilistic analyses of surface and subsurface settlements was conducted considering the spatial variability of the friction angle and reference stiffness modulus,under different volumetric block proportions(Pv)and tunnel volume loss rates(ηt).The non-intrusive random finite difference method was used to investigate the probabilistic characteristics of maximum surface settlement,width of subsurface settlement trough,maximum subsurface settlement,and subsurface soil volume loss rate through Monte Carlo simulations.Additionally,a comparison between stochastic and deterministic analysis results is presented to underscore the significance of probabilistic analysis.Parametric analyses were subsequently conducted to investigate the impacts of the key input parameters in random fields on the settlement characteristics.The results indicate that scenarios with higher Pv or greaterηt result in a higher dispersion of stochastic analysis results.Neglecting the spatial variability of soil properties and relying solely on the mean values of material parameters for deterministic analysis may result in an underestimation of surface and subsurface settlements.From a probabilistic perspective,deterministic analysis alone may prove inadequate in accurately capturing the volumetric deformation mode of the soil above the tunnel crown,potentially affecting the prediction of subsurface settlement.
基金supported by the National Natural Science Foundation of China(Nos.12325201,12272140,and 12322201)。
文摘This study investigates the dynamical behavior of two parallel fluid-conveying pipes by developing a non-planar dynamical model of the two pipes coupled with an intermediate spring. A systematic analysis is conducted to evaluate the effects of spring parameters on the non-planar vibration characteristics and buckling behaviors of the coupled system. The nonlinear governing equations are derived with Hamilton's principle,subsequently discretized through Galerkin's method, and finally numerically solved by the Runge-Kutta algorithm. Based on the linearized equations, an eigenvalue analysis is performed to obtain the coupled frequencies, modal shapes, and critical flow velocities for buckling instability. Quantitative assessments further elucidate the effects of the spring position and stiffness coefficient on the coupled frequencies and critical flow velocities.Nonlinear dynamic analyses reveal the evolution of buckling patterns and bifurcation behaviors between the lateral displacements of the two pipes and the flow velocity. Numerical results indicate that the intermediate spring increases the susceptibility to buckling instability in the out-of-plane direction compared with the in-plane direction. Furthermore, synchronized lateral displacements emerge in both pipes when the flow velocity of one pipe exceeds the critical threshold. This work is expected to provide a theoretical foundation for the stability assessment and vibration analysis in coupled fluid-conveying pipe systems.
基金support from National Outstanding Youth Science Fund(52222314)Near Space Technology and Industry Guidance Fund Project(LKJJ-2023010-01)+3 种基金CNPC Innovation Found(2021DQ02-1001)Dalian Outstanding Youth Science and Technology Talent Project(2023RJ006)Dalian Science and Technology Innovation Project(2022JJ12GX022)Xinghai Talent Cultivation Plan(X20200303).
文摘Sodium-ion hybrid capacitors(SICs),which combine the high energy density of batteries with the high power density and long cycle life of capacitors,are considered promising next-generation energy storage devices.Ensuring the performance of SICs in low-temperature environments is crucial for applications in high-altitude cold regions,where the desolvation process of Na+and the transport process in the solid electrolyte interphase(SEI)are determinant.In this paper,we proposed a multi-ether modulation strategy to construct a solvation sheath with multi-ether participation by modulating the coordination of Na+and solvents.This unique solvation sheath not only reduces the desolvation energy barrier of Na+,but more importantly forms a Na_(2)O-rich inorganic SEI and enhances the ionic dynamics of Na+.Benefiting from the excellent solvation structure design,SICs prepared with this electrolyte can achieve energy density of up to 178 Wh·kg^(-1) and ultra-high power density of 42390 W·kg^(-1) at room temperature.Notably,this SIC delivers record-high energy densities of 149 Wh·kg^(-1) and 119 Wh·kg^(-1) as well as power densities of up to 25200 W·kg^(-1) and 24591 W·kg^(-1) at−20℃ and−40℃,respectively.This work provides new ideas for the development of high-performance SICs for low-temperature operating environments.
基金jointly supported by the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)[grant number SML2023SP240]the National Natural Science Foundation of China[grant number 92158204]。
文摘Cold-surge events can lead to temperature drops and strong winds,which then leads to upper-ocean cooling and deepening of the mixed-layer depth,as illustrated in previous studies.In this study,based on the temperature drop of Shanwei meteorological station,two extreme cold surges and five weak cold invasions in the South China Sea are simulated using an ocean-atmosphere coupled model to investigate their different impacts on the upper-ocean temperature.The diffusion term contributes to the difference in temperature tendency of the upper 20 m,while the advection term contributes to the positive difference from 20 to 80 m of the offshore region and negative difference from 80 to 160 m.In addition,the significant differences are attributed primarily to the influence of the upper-ocean temperature gradient,which subsequently impacts the advection term and results in notable differences in temperature tendency at depths from 80 to 160 m.
基金supported by the National Natural Science Foundation of China(No.41977351)the Natural Science Foundation of Hunan Province,China(No.2020JJ4698)。
文摘Bioremediation became a promising technology to resolve arsenic(As)contamination in aquatic environment.Since monoculture such as microalgae or bacteria was sensitive to environmental disturbance and vulnerable to contamination,green microalgae Chlorella vulgaris and arsenite(As(Ⅲ))-oxidizing bacteria Pseudomonas sp.SMS11 were co-cultured to construct algal-bacterial consortia in the current study.The effects of algae-bacteria(A:B)ratio and exposure As(Ⅲ)concentration on algal growth,As speciation and metabolomic profile were investigated.Algal growth arrested when treated with 100 mg/L As(Ⅲ)without the co-cultured bacteria.By contrast,co-cultured with strain SMS11 significantly enhanced As tolerance in C.vulgaris especially with A:B ratio of 1:10.All the As(Ⅲ)in culture media of the consortia were oxidized into As(Ⅴ)on day 7.Methylation of As was observed on day 14.Over 1% and 0.5% of total As were converted into dimethylarsinic acid(DMA)after 21days cultivation when the initial concentrations of As(Ⅲ)were 1 and 10 mg/L,respectively.Metabolomic analysis was further performed to reveal the response of consortia metabolites to external As(Ⅲ).The enriched metabolomic pathways were associated with carbohydrate,amino acid and energy metabolisms.Tricarboxylic acid cycle and glyoxylate and dicarboxylate metabolism were upregulated under As stress due to their biological functions on alleviating oxidative stress and protecting cells.Both carbohydrate and amino acid metabolisms provided precursors and potential substrates for energy production and cell protection under abiotic stress.Alterations of the pathways relevant to carbohydrate or amino acid metabolism were triggered by energy requirement.
文摘Objective:To provide real-world evidence for the application of first-line dacomitinib treatment for epidermal growth factor receptor(EGFR)21L858R mutant non-small cell lung cancer(NSCLC)patients in China and to explore the factors influencing the efficacy and safety.Methods:A longitudinal,consecutive case-series,multicenter study with mixed prospective and retrospective data was conducted.The primary endpoint was progression-free survival(PFS),and the secondary endpoints included duration of treatment(DOT),overall survival(OS),objective response rate(ORR),disease control rate(DCR)and safety.Results:A total of 155 EGFR 21L858R mutant patients treated with first-line dacomitinib were included.The median follow-up time for these patients was 20.4 months.Among 134 patients with evaluable lesions,the ORR was 70.9%and the DCR was 96.3%.The median PFS was 16.3[95%confidence interval(95%CI),13.7−18.9]months.Multivariate Cox regression analysis suggested that the baseline brain metastasis(BM)status[with vs.without BM:hazard ratio(HR),1.331;95%CI,0.720−2.458;P=0.361]and initial doses(45 mg vs.30 mg:HR,0.837;95%CI,0.427−1.641;P=0.604)did not significantly affect the median PFS.The median DOT was 21.0(95%CI,17.5−24.6)months and the median OS was not reached.Genetic tests were performed in 64 patients after progression,among whom 29(45.3%)patients developed the EGFR 20T790M mutation.In addition,among the 46 patients who discontinued dacomitinib treatment after progression,31(67.4%)patients received subsequent third-generation EGFR-tyrosine kinase inhibitors.The most common grade 3−4 adverse events were rash(10.4%),diarrhea(9.1%),stomatitis(7.1%)and paronychia(4.5%).The incidence of grade 3−4 rash was significantly higher in the 45 mg group than that in the 30 mg group(21.9%vs.7.5%,P=0.042).Conclusions:First-line dacomitinib treatment demonstrated promising efficacy and tolerable adverse events among EGFR 21L858R mutant NSCLC patients in China.
基金supported by National Natural Science Foundation of China(NSFC,Grant No.51972178)Natural Science Foundation of Ningbo(2022J139)Ningbo Yongjiang Talent Introduction Programme(2022A-227-G)
文摘Crystallineγ-Ga_(2)O_(3)@rGO core-shell nanostructures are synthesized in gram scale,which are accomplished by a facile sonochemical strategy under ambient condition.They are composed of uniformγ-Ga_(2)O_(3)nanospheres encapsulated by reduced graphene oxide(rGO)nanolayers,and their formation is mainly attributed to the existed opposite zeta potential between the Ga_(2)O_(3)and rGO.The as-constructed lithium-ion batteries(LIBs)based on as-fabricatedγ-Ga_(2)O_(3)@rGO nanostructures deliver an initial discharge capacity of 1000 mAh g^(-1)at 100 mA g^(-1)and reversible capacity of 600 mAh g^(-1)under 500 mA g^(-1)after 1000 cycles,respectively,which are remarkably higher than those of pristineγ-Ga_(2)O_(3)with a much reduced lifetime of 100 cycles and much lower capacity.Ex situ XRD and XPS analyses demonstrate that the reversible LIBs storage is dominant by a conversion reaction and alloying mechanism,where the discharged product of liquid metal Ga exhibits self-healing ability,thus preventing the destroy of electrodes.Additionally,the rGO shell could act robustly as conductive network of the electrode for significantly improved conductivity,endowing the efficient Li storage behaviors.This work might provide some insight on mass production of advanced electrode materials under mild condition for energy storage and conversion applications.
基金Project supported by the National Natural Science Foundation of China (Nos.12072119,12325201,and 52205594)the China National Postdoctoral Program for Innovative Talents (No.BX20220118)。
文摘Due to the novel applications of flexible pipes conveying fluid in the field of soft robotics and biomedicine,the investigations on the mechanical responses of the pipes have attracted considerable attention.The fluid-structure interaction(FSI)between the pipe with a curved shape and the time-varying internal fluid flow brings a great challenge to the revelation of the dynamical behaviors of flexible pipes,especially when the pipe is highly flexible and usually undergoes large deformations.In this work,the geometrically exact model(GEM)for a curved cantilevered pipe conveying pulsating fluid is developed based on the extended Hamilton's principle.The stability of the curved pipe with three different subtended angles is examined with the consideration of steady fluid flow.Specific attention is concentrated on the large-deformation resonance of circular pipes conveying pulsating fluid,which is often encountered in practical engineering.By constructing bifurcation diagrams,oscillating shapes,phase portraits,time traces,and Poincarémaps,the dynamic responses of the curved pipe under various system parameters are revealed.The mean flow velocity of the pulsating fluid is chosen to be either subcritical or supercritical.The numerical results show that the curved pipe conveying pulsating fluid can exhibit rich dynamical behaviors,including periodic and quasi-periodic motions.It is also found that the preferred instability type of a cantilevered curved pipe conveying steady fluid is mainly in the flutter of the second mode.For a moderate value of the mass ratio,however,a third-mode flutter may occur,which is quite different from that of a straight pipe system.
基金the National Natural Science Foundation of China(Nos.82170998,82201102,62205122)the Postdoctoral Science Foundation Project of China(No.2022M721316)+4 种基金the General program of the Natural Science Foundation of Jilin Province(Nos.YDZJ202201ZYTS017,20220203145SF,20210203087SF,YDZJ202201ZYTS274,YDZJ202201ZYTS080)Hygiene and Health Appropriate Technology Promotion Project of Jilin Province(No.2020S014)the Science and Technology Project of Jilin Province Financial Department(Nos.jcsz202189321,jcsz2021893-15,Zkjc D105181350043103358)Science and Technology Project of Jilin Province Education Department(No.JJKH20221098KJ)the Health Department Research Projects of Jilin Province(No.2022JC076)for financial support.
文摘Antimicrobial photodynamic therapy(aPDT)has been considered a noninvasive and effective modality against the bacterial infection of peri‑implantitis,especially the aPDT triggered by near-infrared(NIR)light due to the large penetration depth in tissue.However,the complexity of hypoxia microenvironments and the distance of aPDT sterilization still pose challenges before realizing the aPDT clinical application.Due to the long lifespan and transmission distance of therapeutic gas molecules,we design a multi-functional gas generator that combines aPDT as well as O_(2) and CO gas release function,which can solve the problem of hypoxia(O_(2))in PDT and the problem of inflammation regulation(CO)in the distal part of peri‑implant inflammation under near-infrared(NIR)irradiation.In the composite nanoplatform that spin-coated on the surface of titanium implants,up-conversion nanoparticles(UCNPs)were involved in converting the NIR to visible,which further excites the partially oxidized stannic sulfide(SnS_(2)),realizing the therapeutic gas release.Indocyanine green(ICG)was further integrated to enhance the aPDT performance(Ti-U@SnS_(2)/I).Therefore,reactive oxygen species(ROS),CO,and O_(2) can be controllably administered via a composite nano-platform mediated by a single NIR light(808 nm).This implant surface modification strategy could achieve great self-enhancement antibacterial effectiveness and regulate the lingering questions,such as relieving the anoxic microenvironment and reaching deep infection sites,providing a viable antibiotic-free technique to combat peri‑implantitis.
基金appreciate the support of the Key Laboratory of Mechanical Structure Optimization&Material Application Technology of Luzhou(No.SCHYZSA-2022-02)the Scientific Research and Innovation Team Program of Sichuan University of Science and Technology(No.SUSE652A004)+1 种基金the Key Laboratory of Intelligent Manufacturing of Construction Machinery Project(No.IMCM202103)the Panzhihua Key Laboratory of Advanced Manufacturing Technology Open Fund Project(No.2022XJZD01)。
文摘In the present work,the laminar plasma surface hardening method is employed to enhance the service life of metal components fabricated from 65 Mn steel.The mechanical and wear behaviors of the laminar plasma surface hardened 65 Mn steel were analyzed.The martensite transition transformation of the temperature of the laminar plasma-hardened 65 ferrite Mn steel was determined by a thermal-solid coupling model.Based on the orthogonal experimental results,the optimal hardening parameters were confirmed.The scanning velocity,quenching distance and arc current are 130 mm/min,50 mm and 120 A,respectively.The pearlites and ferrites are transformed into martensites in the hardened zone,while the ratio of martensite in the heataffected zone decreases with the increase in the hardening depth.Compared to the untreated 65Mn steel,the average hardness increases from 220 HV_(0.2)to 920 HV_(0.2)in the hardened zone and the corresponding absorbed power increases from 118.7 J to 175.5 J.At the same time,the average coefficient of friction(COF)decreases from 0.763 to 0.546,and the wear rate decreases from 5.39×10^(-6)mm^(3)/(N·m)to 2.95×10^(-6)mm^(3)/(N·m),indicating that the wear resistance of 65Mn steel could be significantly improved by using laminar surface hardening.With the same hardening parameters,the depth and width of the hardened zone predicted by the thermal-solid coupling model are 1.85 mm and 11.20 mm,respectively,which are in accordance with the experimental results;depth is 1.83 mm and width is 11.15 mm.In addition,the predicted hardness distributions of the simulation model are in accordance with the experimental results.These results indicate that the simulation model could effectively predict the microstructure characteristics of 65 Mn steel.
基金financially supported by the National Key Re-search and Development Program of China(No.2022YFB3705605)the Science and Technology Major Project of Shaanxi Province of China(No.2020zdzx04-01-02)+1 种基金the National Natural Science Foun-dation of China(No.52101122)the National Key Laboratory Foundation of Science and Technology on Materials under Shock and Impact(No.6142902220202).
文摘Impact deformation behaviors of CT20 alloy with lamellar microstructure(LM),equiaxed microstructure(EM)and bimodal microstructure(BM)at room temperature were systematically investigated in this study.The experimental results indicated the excellent mechanical properties of CT20 alloy with BM un-der dynamic load.The impact toughness of BM specimen(∼118 J/cm^(2))is∼17.5%higher than that of LM specimen and∼33.8%higher than that of EM specimen.The impact energy of EM specimen is the lowest due to the relatively simple equiaxed microstructure.LM specimen can absorb the highest crack initia-tion energy due to the best twinning ability.The highest impact toughness of BM specimen is induced by multi-factor coupling during impact deformation.Finer initial equivalent grain size,smaller lamellar thickness,lamellar induces twinning,finer twins,crack propagation path,and interaction between twins andβlamellar are all factors affecting impact toughness.
基金supported by the National Natural Science Foundation of China (Nos. 11622216 and 51409134)
文摘The nonlinear forced vibrations of a cantilevered pipe conveying fluid under base excitations are explored by means of the full nonlinear equation of motion, and the fourth- order Runge-Kutta integration algorithm is used as a numerical tool to solve the discretized equations. The self-excited vibration is briefly discussed first, focusing on the effect of flow velocity on the stability and post-flutter dynamical behavior of the pipe system with parameters close to those in previous experiments. Then, the nonlinear forced vibrations are examined using several concrete examples by means of frequency response diagrams and phase-plane plots. It shows that, at low flow velocity, the resonant amplitude near the first-mode natural frequency is larger than its counterpart near the second-mode natural frequency. The second-mode frequency response curve clearly displays a softening-type behavior with hysteresis phenomenon, while the first-mode frequency response curve almost maintains its neutrality. At moderate flow velocity, interestingly, the first-mode resonance response diminishes and the hysteresis phenomenon of the second-mode response disappears. At high flow velocity beyond the flutter threshold, the frequency response curve would exhibit a quenching-like behavior. When the excitation frequency is increased through the quenching point, the response of the pipe may shift from quasiperiodic to periodic. The results obtained in the present work highlight the dramatic influence of internal fluid flow on the nonlinear forced vibrations of slender Pipes.
文摘The linkage between Qi and mitochondria was investigated by exploring the effect of Traditional Chinese Medicine (TCM) Qi-invigorating herbs on mitochondrial function at the biochemical and molecular levels. Three Chinese herbs (<i></span><i><span style="font-family:Verdana;">Astragali radix</span></i><span style="font-family:Verdana;">,</span><i><span style="font-family:Verdana;"> Herba cistanche</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Panax ginseng</span></i><span style="font-family:Verdana;"></i>) were used to treat cultured mouse kidney cells and the generation of adenosine triphosphate (ATP) was measured. The Qi-invigorating herb, <i></span><i><span style="font-family:Verdana;">Astragali radix</span></i><span style="font-family:Verdana;"></i>, was selected for further </span></span><span style="font-family:""><span style="font-family:Verdana;">study using additional biological and molecular parameters, including ATP, reactive oxygen species (ROS), mitochondrial membrane potential (MMP),</span><span><span style="font-family:Verdana;"> mtDNA copies, superoxide dismutase (SOD), glutathione (GSH), cell growth, cell viability and transcriptomes. We also chose two concentrations of <i></span><i><span style="font-family:Verdana;">Astragali radix</span></i><span style="font-family:Verdana;"></i> to study the hormetic effect. The results indicated that: 1) Qi-invigorating herbs have significant effects on the function of mitochondria, with ATP production and the antioxidant capacity being significantly enhanced, and ROS le</span></span><span style="font-family:Verdana;">vels being reduced, allowing for a more optimal oxidation environment. The effect of the herbs followed a hormetic curve with a stimulating effect at lower</span><span> </span><span style="font-family:Verdana;">doses but an inhibiting effect at high doses;2) The growth of the cells was not</span><span> </span><span style="font-family:Verdana;">affected despite numerous biochemical changes associated with mitochondrial</span><span> </span><span style="font-family:Verdana;">function, indicating the powerful ability of mitochondria to maintain cellular homeostasis;3) The up-regulation of NOCT gene, related to nicotinamide adenine dinucleotide (NADH) synthesis, offers a molecular basis for the ATP-promoting effect of the Qi-invigorating herbs. This work provides additional insight into the efficacy of TCM herbs from a western perspective.
文摘<div style="text-align:justify;"> Titanium alloy materials are widely used in the marine and aviation fields due to their excellent properties. The submersible sailing on the water surface is faster than underwater diving, so once an accident occurs, the consequences are unimaginable. Based on the failure criterion of the J-K model, this paper uses finite element simulation software to study the impact of impact velocity and impact angle on the collision response of a titanium alloy cylindrical pressure shell, providing a reference for the deep sea titanium alloy pressure shell. </div>
文摘<i><span style="font-family:Verdana;">Astragali Radix </span></i><span style="font-family:Verdana;">(AR), the dried root of legumes, belongs to the Qi-invigorating</span><span style="font-family:""> <span style="font-family:Verdana;">herbs in traditional Chinese medicine and plays an important role in the</span><span style="font-family:Verdana;"> treatment of many diseases. In order to understand the mechanism of action of AR extract. We used AR extract to treat M-1, mouse kidney cells, and used transcriptome sequencing technology to detect the genomic transcription level of the cells under the action of AR at different concentrations and times. The results showed that after a low concentration of AR treatments on the cells, the expression of genes related to cell growth and cellular immune response changed significantly, among which multiple genes are related to mitochondrial function, while high concentrations of AR affected the expression of histones and disease-related genes. It showed that the low concentration of AR extract can achieve the effect of invigorating Qi by regulating the function of mitochondria. In addition, several important genes and pathways were identified as potential targets of AR activation. The research not only clarified the main molecular biological mechanism of AR invigorating Qi, but also provided experimental basis and cellular physiology reference for the further clinical application of AR.
