Design of dense gap-graded friction course mixture

The design procedure of a dense gap-graded friction course（DGGFC） with coarse aggregate void filling method is presented. Testing results show that a DGGFC mixture possesses a dense stone-matrix structure, good stability and almost the same texture depth as stone matrix asphalt （SMA）. It also has a coarse and even surface after paving and has no separation during construction. It is durable and impermeable. It balances and improves the inherent inconsistency of asphalt mixture between the large texture depth for skid resistance and the impermeability for durability. The actual application in the Nanning-Liuzhou Expressway also shows that the performance of the DGGFC is as excellent as that of SMA, while the DGGFC mixture is cheaper than SMA. The DGGFC mixture is good for wearing course of pavement. Further research on DGGFC can be helpful for improving the surface skid resistance, prolonging the life-span period and reducing the construction costs of asphalt pavement.

The effect of dynamical quark mass on the calculation of a strange quark star's structure

We discuss the dynamical behavior of strange quark matter components, in particular the effects of density dependent quark mass on the equation of state of strange quark matter. The dynamical masses of quarks are computed within the Nambu-Jona-Lasinio model, then we perform strange quark matter calculations em- ploying the MIT bag model with these dynamical masses. For the sake of compar- ing dynamical mass interaction with QCD quark-quark interaction, we consider the one-gluon-exchange term as the effective interaction between quarks for the MIT bag model. Our dynamical approach illustrates an improvement in the obtained equation of state values. We also investigate the structure of the strange quark star using Tolman- Oppenheimer-Volkoff equations for all applied models. Our results show that dynamical mass interaction leads to lower values for gravitational mass.

Advanced Alumina and Zirconia Ceramics Produced by the Electroconsolidation Method

The possibility to produce advanced alumina and zirconia ceramics by the electroconsolidation method is studied. The technological parameters of Al2O3 and ZrO2 （3 mass% Y2O3 ） production were developed and optimized. Electroconsolidated alumina and zirconia ceramics have higher values of properties in comparison with ordinary sintered samples in air. Advanced proper- ties of electroconsolidated ceramics are defined by homo- geneous, ultradense and fine-crystalline structure that was formed due to the effect to consolidate the materials to high density for a shortest time.

Calculation of the structural properties of a strange quark star in the presence of a strong magnetic field using a density dependent bag constant

We have calculated the structural properties of a strange quark star with a static model in the presence of a strong magnetic field. To this end, we use the MIT bag model with a density dependent bag constant. To parameterize the density dependence of the bag constant, we have used our results for the lowest order constrained variational calculation of the asymmetric nuclear matter. By calculating the equation of state of strange quark matter, we have shown that the pressure of this system increases by increasing both density and magnetic field. Finally, we have investigated the effect of density dependence of the bag constant on the structural properties of a strange quark star.

Electrolyte-mediated dense integration of graphene-MXene films for high volumetric capacitance flexible supercapacitors

High conductivity two-dimensional(2D)materials have been proved to be potential electrode materials for flexible supercapacitors because of its outstanding chemical and physical properties.However,electrodes based on 2D materials always suffer from limited electrolyte-accessible surface due to the restacking of the 2D sheets,hindering the full utilization of their surface area.In this regard,an electrolyte-mediated method is used to integrate dense structure reduced graphene oxide/MXene(RGM)-electrolyte composite films.In such composite films,reduced graphene oxide(RGO)and MXene sheets are controllable assembly in compact layered structure with electrolyte filled between the layers.The electrolyte layer between RGO and MXene sheets forms continuous ion transport channels in the composite films.Therefore,the RGM-electrolyte composite films can be used directly as self-supporting electrodes for supercapacitors without additional conductive agents and binders.As a result,the composite films demonstrate enhanced volumetric specific capacity,improved volumetric energy density and higher power density compared with both pure RGO electrode and porous composite electrode prepared by traditional methods.Specifically,when the mass ratio of MXene is 30%,the electrode delivers a volumetric specific capacity of 454.9 F·cm^(−3) with a high energy density of 39.4 Wh·L^(−1).More importantly,supercapacitors based on the composite films exhibit good flexibility electrochemical performance.The investigation provides a new approach to synthesize dense structure films based on 2D materials for application in high volumetric capacitance flexible supercapacitors.

Dense Sphene-type Solid Electrolyte Through Rapid Sintering for Solid-state Lithium Metal Battery

The sphene-type solid electrolyte with high ionic conductivity has been designed for solid-state lithium metal battery.However,the practical applications of solid electrolytes are still suffered by the low relative density and long sintering time of tens of hous with large energy consumption.Here,we introduced the spark plasma sintering technology for fabricating the sphene-type Li1.125Ta0.875Zr0.125SiO5 solid electrolyte.The dense electrolyte pellet with high relative density of ca.97.4% and ionic conductivity of ca.1.44×10^-5S/cm at 30℃ can be obtained by spark plasma sintering process within the extremely short time of only ca.0.1h.Also the solid electrolyte provides stable electrochemical window of ca.6.0V(vs.Li^+/Li)and high electrochemical interface stability toward Li metal anodc.With the enhanced interfacial contacts between electrodes and electrolyte pellet by the in-situ formed polymer electrolyte,the solid-state lithium metal battery with LiFePO4 cathode can deliver the initial discharge capacity of ca.154mA·h/g at 0.1C and the reversible capacity of ca.132mA·h/g after 70 cycles with high Coulombic efficienty of 99.5% at 55℃.Therefore,this study demonstrates a rapid and energy efficient sintering strategy for fabricating the solid electrolyte with dense structure and high ionic conductivity that can be practically applied in solid-state lithium metal batteries with high energy densities and safeties.

Nodes2STRNet for structural dense displacement recognition by deformable mesh model and motion representation

Displacement is a critical indicator for mechanical systems and civil structures.Conventional vision-based displacement recognition methods mainly focus on the sparse identification of limited measurement points,and the motion representation of an entire structure is very challenging.This study proposes a novel Nodes2STRNet for structural dense displacement recognition using a handful of structural control nodes based on a deformable structural three-dimensional mesh model,which consists of control node estimation subnetwork(NodesEstimate)and pose parameter recognition subnetwork(Nodes2PoseNet).NodesEstimate calculates the dense optical flow field based on FlowNet 2.0 and generates structural control node coordinates.Nodes2PoseNet uses structural control node coordinates as input and regresses structural pose parameters by a multilayer perceptron.A self-supervised learning strategy is designed with a mean square error loss and L2 regularization to train Nodes2PoseNet.The effectiveness and accuracy of dense displacement recognition and robustness to light condition variations are validated by seismic shaking table tests of a four-story-building model.Comparative studies with image-segmentation-based Structure-PoseNet show that the proposed Nodes2STRNet can achieve higher accuracy and better robustness against light condition variations.In addition,NodesEstimate does not require retraining when faced with new scenarios,and Nodes2PoseNet has high self-supervised training efficiency with only a few control nodes instead of fully supervised pixel-level segmentation.

Highly oriented MXene/polyvinyl alcohol films prepared by scalable layer-by-layer blade coating for efficient electromagnetic interference shielding and infrared stealth

Controlling the orientation of two-dimensional MXene within layered films is essential to optimize or tune their mechanical properties and electromagnetic interference shielding(EMI)performance,but achieving the high orientation MXene layers on an industrial scale remains a challenging goal.In this paper,a scalable layer-by-layer blade coating(LbLBC)method was employed to fabricate highly oriented MXene/polyvinyl alcohol(PVA)films.During the LbLBC process,MXene/PVA colloid suffered a strong shearing effect,which induced the ordered alignment of MXene nanosheets along the direction of the blade movement.The orientation of MXene can be effectively adjusted by changing the scraping gap of LbLBC,achieving a maximum Herman orientation factor f of 0.81.As a result,the mechanical properties and EMI performance of the as-prepared MXene/PVA films are in direct proportion to their orientation,with the optimal values of tensile strength of 145.5 MPa,fracture strain of 19.6%,toughness of 17.7 MJ·m^(−3),and EMI shielding effectiveness of 36.7 dB.Furthermore,the inherently low mid-infrared(mid-IR)emissivity of MXene,combined with the densely oriented structure affords the composite films with IR stealth,resulting in a substantial decrease from 150 to 66.1℃in the radiative temperature of a surface.Conclusively,these scalable MXene/PVA films exhibit remarkable potential for integration into the next generation of multifunctional protective camouflage materials.