摘要：This paper proposes a novel collision post structure designed to improve the crashworthiness of subway cab *** structure provides two innovative features:1)a simpler connection between the post and the car roof,which gives a more reasonable load transfer path to reduce the stress concentration at the joint;and 2)a stiffness induction design that provides an ideal deformation model to protect the safe space of the cab *** novel collision post structure was evaluated with finite element analysis,and a prototype cab car was mechanically *** results demonstrate that the deformation response was stable and agreed well with the expected ideal *** maximum load was 874.17 kN and the responses remained well above the elastic design load of 334 kN as required by the design *** addition,there was no significant tearing failure during the whole test ***,the novel collision post structure proposed has met the requirements specified in new standard to improve the crashworthiness of subway cab ***,the energy absorption efficiency and light weight design highlights were also summarized and discussed.

摘要：This work aimed to quantify the physical and mechanical behavior of three-dimensional microstructures in rocks under uniaxial compression.A high-precision in situ XCT(X-ray transmission computed tomography)technology was applied to investigating the behavior of mineral grains in sandstone:the movement,the rotation deformation,and the principal strains between fault zone and non-fault *** results indicate that after unloading,the shear strain of mineral grains is periodic in the radial direction,the strain of mineral grains in the fracture zone is about 30 times of the macro strain of the specimen,which is about 5 times in the non-fracture zone,and the shear strain near the fault zone is larger than the compressive strain,and there is the shear stress concentration feature.

摘要：Solution and quenching heat treatments are generally carried out in a roller hearth furnace for large-scale thick aluminum alloy ***,the asymmetric or uneven spray water flow rate is inevitable under industrial production conditions,which leads to an asymmetric residual stress *** spray quenching treatment was conducted on self-designed spray equipment,and the residual stress along the thickness direction was measured by a layer removal method based on *** the asymmetric spray quenching condition,the subsurface stress of the high-flow rate surface was lower than that of the low-flow rate surface,and the difference between the two subsurface stresses increased with the increase in the difference in water flow *** subsurface stress underneath the surface with a water flow rate of 0.60 m^(3)/h was 15.38 MPa less than that of 0.15 m^(3)/*** simulated residual stress by finite element(FE)method of the high heat transfer coefficient(HTC)surface was less than that of the low HTC surface,which is consistent with the experimental *** FE model can be used to analyze the strain and stress evolution and predict the quenched stress magnitude and distribution.

摘要：In this paper,we consider a multi-UAV surveillance scenario where a team of unmanned aerial vehicles(UAVs)synchronously covers an area for monitoring the ground *** this scenario,we adopt the leader-follower control mode and propose a modified Lyapunov guidance vector field(LGVF)approach for improving the precision of surveillance trajectory ***,in order to adopt to poor communication conditions,we propose a prediction-based synchronization method for keeping the formation ***,in order to adapt the multi-UAV system to dynamic and uncertain environment,this paper proposes a hierarchical dynamic task scheduling *** this architecture,we firstly classify all the algorithms that perform tasks according to their functions,and then modularize the algorithms based on plugin ***,integrating the behavior model and plugin technique,this paper designs a three-layer control flow,which can efficiently achieve dynamic task *** order to verify the effectiveness of our architecture,we consider a multi-UAV traffic monitoring scenario and design several cases to demonstrate the online adjustment from three levels,respectively.

摘要：The photocatalytic activity of a semiconductor‐based photocatalyst largely depends on the semiconductor’s intrinsic crystal and electronic *** have prepared two types of La and Cr co‐doped SrTiO3photocatalysts(SrTiO3(La,Cr))using the polymerized complex method(PCM)and sol‐gel hydrothermal method(SHM).Under?>420‐nm visible light irradiation,only the Pt‐loaded SrTiO3(La,Cr)prepared by the SHM showed efficient photocatalytic activities for both H2evolution in the presence of an I?sacrificial reagent and for Z‐scheme overall water splitting when it was coupled with the Pt‐loaded WO3in the presence of I?and IO3?as the shuttle redox *** superior photocatalytic activity of SrTiO3(La,Cr)prepared by the SHM has been ascribed to its more negative conduction‐band position,higher carrier concentration,and higher carrier mobility,demonstrating that the design and synthesis of an H2‐evolution photocatalyst with appropriate electronic properties is crucial for achieving Z‐scheme overall water splitting.

摘要：Artificial neural networks have dramatically improved the performance of many machine-learning applications such as image recognition and natural language processing. However, the electronic hardware implementations of the above-mentioned tasks are facing performance ceiling because Moore’s Law is slowing down. In this article, we propose an optical neural network architecture based on optical scattering units to implement deep learning tasks with fast speed, low power consumption and small *** optical scattering units allow light to scatter back and forward within a small region and can be optimized through an inverse design method. The optical scattering units can implement high-precision stochastic matrix multiplication with mean squared error < 10-4 and a mere 4*4 um2 ***, an optical neural network framework based on optical scattering units is constructed by introducing "Kernel Matrix", which can achieve 97.1% accuracy on the classic image classification dataset MNIST.

摘要：The flammability of thermoplastic polyesters and the subsequent heavy smoke and severe melt drips formed after ignition are the main obstacles hindering their widespread application. In this study, a novel ionic monomer containing sulfonate and benzimidazole was synthesized and incorporated into the main chain of poly(ethylene terephthalate)(PET, used as a model thermoplastic polyester) by melt copolymerization. The synergetic effect of ionic aggregation and carbonization endowed the obtained copolyester with high melt viscosity and excellent char-forming ability at high temperatures. The copolyester having a monomer content of 8 mol.% easily achieved the Underwriters Laboratories Inc 94(UL-94) V-0 flammability rating without dripping and the limiting oxygen index value reached 33.0 vol.%.In addition, the total smoke production, peak heat release rate,and maximum CO production decreased by 45.2%, 60.5%, and75.0%, respectively, compared with those of PET. In addition,the copolyester was spinnable, and showed greater adsorption efficiency(99.6%) for a cationic dye from solution compared to PET(6.5%), demonstrating the excellent affinity of the copolyester for the cationic dye. The obtained inherently firesafe PET copolyester has great potential for applications in flame retardant textiles, artwork base materials, and decorative materials for transportation applications.

摘要：Zinc-air batteries(ZnABs) with high theoretical capacity and environmental benignity are the most promising candidates for next-generation electronics. However, their large-scale applications are greatly hindered due to the lack of high-efficient and cost-effective electrocatalysts. Transition metal phosphides(TMPs) have been reported as promising electrocatalysts. Notably,(Ni_(1-x)Cr_(x))_(2) P(0≤x≤0.15) is an unstable electrocatalyst, which undergoes in-situ electrochemical oxidation during the initial oxygen evolution reaction(OER) and even in the activation cycles, and is eventually converted to Cr-NiOOH serving as the actual OER active sites with high efficiency. Density functional theory(DFT) simulations and experimental results elucidate that the OER performance could be significantly promoted by the synergistic effect of surface engineering and electronic modulations by Cr doping and in-situ phase transformation. The constructed rechargeable ZnABs could stably cycle for more than 208 h at 5 m A cm^(-2), while the voltage degradation is negligible. Furthermore, the developed catalytic materials could be assembled into flexible and all-solid-state Zn ABs to power wearable electronics with high performance.

摘要：The multiple quantum transitions within d-band correlation oxides such as rare-earth nickelates(RENiO_(3))triggered by critical temperatures and/or hydrogenation opened up a new paradigm for correlated electronics applications,*** electric field sensor,bio-sensor,and neuron synapse logical ***,these applications are obstructed by the present ineffectiveness in the thin film growth of the metastable RENiO_(3)with flexibly adjustable rare-earth compositions and electronic ***,we demonstrate a metal-organic decompositions(MOD)approach that can effectively grow metastable RENiO_(3)covering a large variety of the rare-earth composition without introducing any vacuum *** the previous chemical growths for RENiO_(3)relying on strict interfacial coherency that limit the film thickness,the MOD growth using reactive isooctanoate percussors is tolerant to lattice defects and therefore achieves comparable film thickness to vacuum *** indicated by positron annihilation spectroscopy,the RENiO_(3)grown by MOD exhibit large amount of lattice defects that improves their hydrogen incorporation amount and electron transfers,as demonstrated by the resonant nuclear reaction analysis and near edge X-ray absorption fine structure *** effectively enlarges the magnitude in the resistance regulations in particular for RENiO_(3)with lighter RE,shedding a light on the extrinsic regulation of the hydrogen induced quantum transitions for correlated oxides semiconductors kinetically via defect engineering.

摘要：Interfaces play critical roles in electronic devices and provide great diversity of film morphology and device *** retrospect the substrate mediated vacuum film growth of benchmark high mobility material 2,7-dioctyl[1]benzothieno[3,2-b]benzothiophene(C8-BTBT)and the interface electronic *** film growth of C8-BTBT molecules is diversified depending on the substrate-molecule and molecule-molecule *** atomic smooth substrates C8-BTBT film grows in layer-by-layer mode while on coarse substrate it grows in islands *** initial molecular layer at dielectric,semiconductor and conductive substrates displays slight different lattice *** initial molecule orientation depends on the substrate and will gradually change to standing up configuration as in bulk phase.C8-BTBT behaves as electron donor when contacting with dielectric and stable conductive *** usually induces a dipole layer pointing to C8-BTBT and an upward bend bending in C8-BTBT side toward the *** it is air stable,C8-BTBT is chemically reactive with some transition metals and *** orientation change from lying down to standing up in the film usually leads to decrease of ionization *** article provides insights to the interface physical and chemical processes and suggestions for optimal design and fabrication of C8-BTBT based devices.