In the era of the internet revolutionaries’ physical objects exchange data through technology. As a result, there is an exponential increase in the number of devices now connected to the internet. Devices such as sma...
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This study investigates the effect of defect engineering on the catalytic activity of a NiPS3 monolayer catalyst for the hydrogen evolution reaction(HER).Three different types of vacancies on the basal plane of the mo...
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This study investigates the effect of defect engineering on the catalytic activity of a NiPS3 monolayer catalyst for the hydrogen evolution reaction(HER).Three different types of vacancies on the basal plane of the monolayer are explored through a multi-step mechanism involving the dissociative adsorption of a water molecule and subsequent electrochemical adsorption of the dissociated ***-formation of vacancies in both Ni and S sites is found to be the most effective in enhancing the catalytic performance of the monolayer.A key resource for the reaction thermodynamics is the S-substitution-like physisorption of a water molecule on a vacant S site,followed by the dissociative occupation of OH and H into vacant sites of S and Ni elements,boosted by the NiS di-vacancy configuration with low activation energy *** reveals the highest contribution of bonding orbitals to the monolayer-H bond makes it the most desirable defect engineering approach for transition metal phosphorus chalcogenides with high HER ***,this study highlights the significance of controlled defect engineering in augmenting the catalytic performance of NiPS3 monolayer catalysts for HER.
The flow around a circular cylinder for Re=1000 is characterized by flow separation and Karman vortex *** typical flow features can be captured to study the correlation between fluid fields and sound *** this paper,th...
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The flow around a circular cylinder for Re=1000 is characterized by flow separation and Karman vortex *** typical flow features can be captured to study the correlation between fluid fields and sound *** this paper,the three-dimensional circular cylinder is taken as the research object,and the probes of surface fluctuating pressure and far field sound pressure are arranged every 10°.The directional diagram and the coherence of fluctuating pressure and sound pressure are *** relationship between the flow mode and hydrodynamic noise is studied by using dynamic mode decomposition(DMD).The characteristics of the dipole and quadrupole sound source term of a long span cylinder are *** results show that at the angles between 30°–120°and 190°–350°,the fluctuating pressure contributes more to the generation of dipole *** quadrupole sound source shows three-dimensional effects,which is more obvious in a cylinder with large spanwise length.
Point clouds, image data, and corresponding processing algorithms are intensively investigated to create and enrich Building Information Models (BIM) with as-is information and maintain their value across the building...
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Quantum spin Hall (QSH) insulators, with their unique helical edge states where counterpropagating edge channels possess opposite spins, have attracted broad interest across various fields. While the exact quantizatio...
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Quantum spin Hall (QSH) insulators, with their unique helical edge states where counterpropagating edge channels possess opposite spins, have attracted broad interest across various fields. While the exact quantization of spin Hall conductance (SHC) is elusive in realistic materials due to intrinsic spin mixing effects, the near quantization, as a compromised definition of the QSH effect, cannot be captured by rigorous topological invariants. In this Letter, we present a universal symmetry indicator for diagnosing the QSH effect in realistic materials, termed spin U(1) quasisymmetry. Such a symmetry eliminates the first-order spin-mixing perturbation and thus protects the near-quantization of SHC, applicable to time-reversal-preserved cases with either Z2=1 or Z2=0, as well as time-reversal-broken scenarios. We propose that spin U(1) quasisymmetry is hidden in the subspace spanned by the doublets with unquenched orbital momentum and emerges when SOC is present, which can be realized in 19 crystallographic point groups. Our theory is applied to identify previously overlooked QSH phases such as time-reversal-preserved even spin Chern phase and time-reversal-broken phase, as exemplified by twisted bilayer transition metal dichalcogenides, monolayer RuBr3, and monolayer FeSe. Our work provides a comprehensive symmetry-based framework for understanding the QSH effect and significantly expands the material pool for the screening of exemplary material candidates.
Tungsten-bronze-type material Ba_(6-3x)RE_(8+2x)Ti_(18)O_(54),(RE=rare earth elements)is an important microwave dielectric that has shown great promises for future miniaturization of microwave devices because of its h...
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Tungsten-bronze-type material Ba_(6-3x)RE_(8+2x)Ti_(18)O_(54),(RE=rare earth elements)is an important microwave dielectric that has shown great promises for future miniaturization of microwave devices because of its high dielectric constant,low loss,and tunabilities,and there is still much room for *** their proven predictive power,first-principles calculations may greatly help accelerate materials optimization by reducing or eliminating the expensive and time-consuming experimental trial-and-error ***,microwave dielectrics such as the tungsten-bronzetype materials are rather complex systems with unit cells containing hundreds or thousands of atoms,making ab initio calculations prohibitively *** this work,we propose an elemental-unit decomposition(EUD)technique that can drastically reduce the computational effort of predicting the properties of complex microwave dielectrics and demonstrate its accuracy and *** approach facilitates first-principles prediction and design of complex microwave dielectric materials that would otherwise be extremely difficult.
This paper presents a numerical study on focused wave and current interactions with a *** cylinder is moving in the opposite direction to the wave *** effective computational decomposition method is adopted to reduce ...
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This paper presents a numerical study on focused wave and current interactions with a *** cylinder is moving in the opposite direction to the wave *** effective computational decomposition method is adopted to reduce the calculation resources.A potential solver high-order spectral(HOS)method is applied to generate focused wave field,while our in-house computational fluid dynamics(CFD)solver naoe-FOAM-SJTU with overset grid takes the charge of achieving the viscous effect around the moving *** viscous domain moving with the cylinder thus the size and mesh grids in computational domain is greatly *** pressure on cylinder surface and wave fields around cylinder are compared with experimental data,shows a well ***,the scattering wave field and vortex shedding are *** the existence of moving cylinder,the classical scattering wave types are still observed.
The present study performs the transient analysis of sandwich plates under the influence of underwater blast loading. The sandwich plate consists of a functionally graded (FG) porous core reinforced with graphene nano...
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Wall-modeled large eddy simulation(WMLES)is used to investigate turbulent fluctuations around an axisymmetric body of *** study focuses on evaluating the ability of WMLES to predict the fluctuating flow over the axisy...
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Wall-modeled large eddy simulation(WMLES)is used to investigate turbulent fluctuations around an axisymmetric body of *** study focuses on evaluating the ability of WMLES to predict the fluctuating flow over the axisymmetric hull and analyzing the evolution of turbulent fluctuations around the *** geometry is the DARPA SUBOFF bare model and the Reynolds number is 1.2×10^(7),based on the free-stream velocity and the length of the ***-wall flow structures and complex turbulent fluctuation fields are successfully ***-averaged flow quantities,such as time-averaged pressure and skin-friction coefficients,and time-averaged velocity profiles on the stern,achieved great agreements between WMLES results and experimental ***-similarity of time-averaged velocity defects within a self-similar coordinate up to twelve diameters from the tail.A comprehensive analysis of second-order statistics in the mid-body,stern,and wake regions is *** results agree well with experimental data and previous wall-resolved large eddy simulation(WRLES)results about root mean square(rms)of radial and axial fluctuating velocities at the *** fluctuations including turbulent kinetic energy(TKE)and second-order velocity statistics are identified as dual peak behavior and non-self-similar over the wake length,consistent with previous findings in the *** assessment enhances the understanding of WMLES capabilities in capturing complex fluctuating flow around axisymmetric geometries.
Considering the demanding of grid requirements for high-Reynolds-number wall-bounded flow,the wall-modeled large-eddy simulation(WMLES)is an attractive method to deal with near wall ***,the effect of subgrid-scale(SGS...
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Considering the demanding of grid requirements for high-Reynolds-number wall-bounded flow,the wall-modeled large-eddy simulation(WMLES)is an attractive method to deal with near wall ***,the effect of subgrid-scale(SGS)models for wall-bounded turbulent flow in combination with wall stress models is still *** this paper,turbulent channel flow at Reτ=1000 are numerically simulated by WMLES in conjunction with four different SGS models,i.e.,the wall-adapting local eddy-viscosity model,the dynamic Smagorinsky model,the dynamic SGS kinetic energy model and the dynamic Lagrangian *** mean velocity profiles are compared with the law of the wall,and the velocity fluctuations are compared with direct numerical simulation *** energy spectrum of velocity and wall pressure fluctuations are presented and the role of SGS models on predicting turbulent channel flow with WMLES is discussed.
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