The development of direct methanol fuel cells (DMFCs) is limited by the slow kinetics of anodic methanol oxidation (MOR), and Pt-based materials have been recognized as the most promising catalysts for MOR. Alloying P...
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The development of direct methanol fuel cells (DMFCs) is limited by the slow kinetics of anodic methanol oxidation (MOR), and Pt-based materials have been recognized as the most promising catalysts for MOR. Alloying Pt with other transition metals is an effective strategy for improving the catalytic performance of Pt-based catalysts. Rare earth (RE) metals are considered favorable elements for modulating catalytic activity owing to their unique electronic structures and electronegativity. In this work, a series of Pt-Ru-RE ternary alloys was synthesized via a potassium vapor reduction method, and the mass activity of the Pt2.7Ru0.3Sc alloy was observed to be 1.03 A mgpt-1, which is almost four times that of Pt9Ru alloy (0.21 A mgpt-1) and more than twice that of Pt3Sc alloy (0.42 A mgpt-1). Moreover, the Pt2.7Ru0.3Sc alloy exhibited superior stability that could be activated repeatedly. Experiments and theoretical calculations revealed that Sc regulates the electronic structure of the Pt2.7Ru0.3Sc alloy and promotes the d-band center of superficial Pt downward, weakening the Pt-CO binding strength. Additionally, Ru was favorable for *OH adsorption, which was beneficial for the removal of the poisonous intermediate (*CO), and the synergistic effects enhanced the activity and stability of Pt2.7Ru0.3Sc alloy catalyst for MOR.
Scope: Manno-oligosaccharides from cassia seed gum (CMOS) have demonstrated anti-inflammatory and regulatory effects on cholesterol metabolism. However, their protective effects against the progression of atherosclero...
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Scope: Manno-oligosaccharides from cassia seed gum (CMOS) have demonstrated anti-inflammatory and regulatory effects on cholesterol metabolism. However, their protective effects against the progression of atherosclerosis (AS) and underlying molecular mechanisms have not been investigated. This study investigates the anti-atherosclerotic effects of CMOS on ApoE(-/-) *** and results: CMOS are supplemented in atherosclerotic male ApoE(-/-) mice fed with a high-fat-high-cholesterol diet (HFHCD). After the 12-week intervention, CMOS at 1200 mg kg(-1)bw d(-1) significantly decrease the atherosclerotic lesion area by 0.63-fold and the aortic arch lesion size by 0.63-fold when compared to the HFHCD group. Moreover, inflammation in atherosclerotic lesions is reduced by CMOS intervention, and the levels of serum lipids and inflammatory cytokines are decreased. The number of goblet cells and the expression of intestinal epithelial tight junction proteins in the H-CMOS group increase, thus indicating that CMOS can restore intestinal barrier integrity in atherosclerotic mice. Furthermore, CMOS reshape the unbalanced gut microbiota in ApoE(-/-) mice caused by HFHCD, and reduce the relative abundance of Desulfovibrio and Faecalibaculum that exhibits positive relationships with ***: CMOS inhibit inflammation, alter intestinal barrier integrity, and regulate gut microbiota to attenuate AS in ApoE(-/-) mice.
Lateral-confined coaxial jet diffusion flame is common in micro thrusters,and the specific impulse is mainly obtained through thermodynamic calculations with an assumption of fuel combustion with an equivalence ratio,...
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Lateral-confined coaxial jet diffusion flame is common in micro thrusters,and the specific impulse is mainly obtained through thermodynamic calculations with an assumption of fuel combustion with an equivalence ratio,regardless of the stability of the combustion ***,the flame behavior plays an important impact on the performance of a micro thruster through the varied combustion *** stability of confined coaxial jet diffusion flames with air coflow was studied by experiments and numerical ***,hydrogen,and propane were used as *** attachment,liftoff,blowout(extinction limits of lifted flame),and blowoff(extinction limits of attached flame) behaviors with the effect of confinement ratios and fuel properties were focused *** the range of the jet flow velocity in this research,the hydrogen flame is always attached to the jet exit,the flame tip goes from closed to open as the jet velocity increases,while the flame transitions from attachment to liftoff in the case of CH_(4) and C_(3)H_(8) .Further,in a narrow confined space,the attached flame for both CH4 and C_(3)H_(8) undergoes liftoff followed by ***,in a space with a high confinement ratio,the CH4 flame transitions directly from attachment to *** critical modified Craya-Curtet number,which is used to predict the onset of the recirculation,is determined through simulation and experiment,and the number is about *** work provides valuable data on flame stability inside a confined space and gives insights into the design of a thruster.
PurposeSports bras can effectively reduce breast displacement, alleviate breast pain and protect the breast. Different bra components have different effects on breast support. This study aims to explore the quantitati...
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PurposeSports bras can effectively reduce breast displacement, alleviate breast pain and protect the breast. Different bra components have different effects on breast support. This study aims to explore the quantitative relationship between bra components and vibration reduction ***/methodology/approachTo understand the effects of different bra component parameters on breast support, 30 sports bras were fabricated with precise component parameters. The dynamic vertical breast displacement when wearing each sports bra was monitored using motion capture technology. The breast displacement data from five breast positions was used to analyze the overall vertical displacement of the breast. To address variability due to differences in human anatomy, the experiments were conducted on a custom-made manikin prepared using three-dimensional *** with bare breasts, breasts supported by bras made with high-elastic-modulus cup materials, high-elastic-modulus shoulder strap materials and polyester underbands exhibited reduced vertical displacement during physical activity. Structurally, bras with higher cup heights, shorter strap lengths and smaller underband circumferences were associated with reduced overall breast displacement during physical ***/valueBy systematically studying the effects of different bra components on breast support, this study provides valuable insight and recommendations for the design and materials selection of sports bras.
A hypersonic plasma sheath is an unmagnetized, weakly ionized, and inhomogeneous plasma flow that causes a blackout in radio communication. Studying the propagation of electromagnetic waves in a plasma flow is of sign...
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A hypersonic plasma sheath is an unmagnetized, weakly ionized, and inhomogeneous plasma flow that causes a blackout in radio communication. Studying the propagation of electromagnetic waves in a plasma flow is of significant importance for addressing potential communication disruptions. The discontinuous Galerkin time domain method based on the Z-transform for dispersive media is derived, and the derivation of the Z-transformation is concise and effective. According to different sizes of the plasma parameter, the non-uniform flow field was divided into two enhancement regions and two attenuation regions. By observing the changes in amplitude and phase of electromagnetic fields in different regions of the flow field, the effects of enhancement and attenuation regions on electromagnetic waves can be clearly observed. When the plasma flow field has a significant effect on electromagnetic scattering, regions with different parameters in the flow field exhibit different or even opposite changes in the amplitude and phase of the electromagnetic field. The effects of the enhanced and attenuated regions on electromagnetic scattering can cancel each other out. Under different band conditions, two regions play a dominant role in electromagnetic scattering. The dust plasma flow field was expressed by the relative dielectric constant of weakly ionized dust plasma, and the influence of the dust plasma on electromagnetic scattering was studied. The influence of plasma flow on electromagnetic scattering is weakened by dust particles. This study provides new insights into the influence of non-uniform flow fields on incident waves.
Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil *** application has emerged as a promising solution for ...
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Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil *** application has emerged as a promising solution for addressing these *** this study,we investigated the effects of four biochar application rates(no biochar(N)=0 t ha^(-1),low(L)=3 t ha^(-1),medium(M)=6 t ha^(-1),and high(H)=9 t ha^(-1))under film mulching and no mulching conditions over three growing *** assessed the impacts on GHG emissions,soil organic carbon sequestration(SOCS),and maize yield to evaluate the productivity and sustainability of farmland *** results demonstrated that mulching increased maize yield(18.68-41.80%),total fixed C in straw(23.64%),grain(28.87%),and root(46.31%)biomass,and GHG emissions(CO_(2),10.78%;N_(2)O,3.41%),while reducing SOCS(6.57%)and GHG intensity(GHGI;13.61%).Under mulching,biochar application significantly increased maize yield(10.20%),total fixed C in straw(17.97%),grain(17.69%)and root(16.75%)biomass,and SOCS(4.78%).Moreover,it reduced the GHG emissions(CO_(2),3.09%;N_(2)O,6.36%)and GHGI(12.28%).These effects correlated with the biochar addition rate,with the optimal rate being 9.0 t ha^(-1).In conclusion,biochar application reduces CO_(2) and N_(2)O emissions,enhances CH_(4) absorption,and improves maize yield under film *** also improves the soil carbon fixation capacity while mitigating the warming potential,making it a promising sustainable management method for mulched farmland in semiarid areas.
To maintain the stability of the inter-satellite link for gravitational wave detection,an intelligent learning monitoring and fast warning method of the inter-satellite link control system failure is *** from the trad...
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To maintain the stability of the inter-satellite link for gravitational wave detection,an intelligent learning monitoring and fast warning method of the inter-satellite link control system failure is *** from the traditional fault diagnosis optimization algorithms,the fault intelligent learning method pro-posed in this paper is able to quickly identify the faults of inter-satellite link control system despite the existence of strong cou-pling *** constructing a two-layer learning network,the method enables efficient joint diagnosis of fault areas and fault *** simulation results show that the average identification time of the system fault area and fault parameters is 0.27 s,and the fault diagnosis efficiency is improved by 99.8%compared with the traditional algorithm.
Lead-free tin halide perovskite solar cells (TPSCs) have recently made significant progress in power conversion efficiency (PCE). However, the presence of mismatched energy levels and weak interlayer interactions betw...
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Lead-free tin halide perovskite solar cells (TPSCs) have recently made significant progress in power conversion efficiency (PCE). However, the presence of mismatched energy levels and weak interlayer interactions between the electron transport materials (ETMs) and tin perovskites has limited the achievable PCE. Here, a new fluorinated fullerene derivative, C60-FTPA (F12), was designed and synthesized to construct a binary ETM with C60-ETPA (F6) reported in our group, resulting in a reduction in defects and improved molecular structure ordering. Furthermore, the binary ETM exhibited a stronger interaction with the tin perovskite and delivered a PCE up to 11.93%.
Wolbachia is a maternally inherited endosymbiont of the phylum a-Proteobacteria that is found widely in arthropods and nematodes. Cytoplasmic incompatibility (CI) is the commonest endosymbiotic manipulation among arth...
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Wolbachia is a maternally inherited endosymbiont of the phylum a-Proteobacteria that is found widely in arthropods and nematodes. Cytoplasmic incompatibility (CI) is the commonest endosymbiotic manipulation among arthropods, namely reduced embryo viability when Wolbachia-infected males fertilize Wolbachia-uninfected *** this study, endosymbiont infection was investigated and crossing experiments were performed in the wing-dimorphic cricket Velarifictorus aspersus (Walker) (Orthoptera: Gryllidae) to clarify the effects of Wolbachia on host *** the tested individuals were infected with two Wolbachia strains, wAsp-a and wAsp-f, which belong to supergroup A and supergroup F, *** were no obvious differences in the duration of nymph development or the proportions of females between the Wolbachia-infected and Wolbachia-free lines. However, crossing Wolbachia-infected males with uninfected females reduced the hatching rate by 28% compared with that when infected males were crossed with infected females. The number of eggs laid by Wolbachia-free females was significantly lower than laid by infected females, either mating with infected males or uninfected *** results suggest that Wolbachia induced incomplete CI and enhanced female fertility in V. aspersus. Because no homologous cifA and cifB genes, which are involved in CI, were found in supergroups C, D and F, it might be considered that the CI of V. aspersus was induced by strain wAsp-a of supergroup A. Moreover, the significant increase in the density of wAsp-a Wolbachia with nymph development might be related to the regulation of CI.
Background: Nowadays, numerical algorithms make it possible to more accurately simulate the behavior of cardiac tissue, and in particular its electrical activity, in order to identify possible cardiac pathologies. Num...
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Background: Nowadays, numerical algorithms make it possible to more accurately simulate the behavior of cardiac tissue, and in particular its electrical activity, in order to identify possible cardiac pathologies. Numerical methods used to simulate cardiac electrical activity, governed by unsteady non-linear PDEs, require very high computation times. Objective: In this paper, we propose a new numerical modeling of electrical activity in cardiac tissue using a new robust and rapid High-Order Implicit Algorithms (HOIAs) based on the Asymptotic Numerical Method (ANM) and meshless techniques. Methods: The numerical modeling is based on a time discretization, a homotopy transformation, a Taylor series representation, a meshless method and a continuation method. Two time steps are introduced: the first is directly linked to the scheme in time (small time step) and the second is linked to the continuation step (big time step). We develop three HOIA variants, using three meshless methods: Spectral Chebyshev Method, Radial Point Interpolation Method and Radial Basis Functions Method. Results and Conclusion : Using these three algorithms, in the case of the FitzHugh-Nagumo and Aliev- Panfilov ion kinetics models, we analyze the influence of algorithm parameters on CPU computation time and response quality. In this study, we will discuss the influence of the choice of the small time step on the big time step depending on the spatial discretization parameters, as well as the Asymptotic Numerical Method parameters (truncation order and precision parameter). The robustness, the efficiency and the utility of the proposed algorithms are demonstrated in the example of cardiac tissue in 2D case.
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