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Magnetic skyrmioniums—with a composite structure comprising two skyrmions with opposite topological charges, exhibit unique dynamic behaviors that are crucial for technological advancements and have application potential for high-density and nonvolatile memory. This study explores the impact of periodic perpendicular magnetic anisotropy (PMA) and damping gradients on skyrmioniums. Utilizing the object oriented micromagnetic framework for detailed simulations, the effective control and enhancement of the skyrmionium stability and mobility through the periodic modulation of PMA and damping gradients is demonstrated. The results demonstrate the dynamic behavior and stability control of skyrmioniums in periodic PMA/damping gradient nanowires. Moreover, the critical influence of the periodic gradient on the skyrmionium motion and stability is highlighted. The results present new avenues for developing advanced memory technologies, leveraging skyrmionium's unique nonlinear behaviors to improve the device performance and reliability. [ABSTRACT FROM AUTHOR]

A novel embedded GFRP grid framework-UHPC composite plate without steel rebar was proposed to solve the problems of conventional reinforced concrete plate, such as heavy weight, easily cracking and poor durability. The composite plate is expected to be superior in mechanical mechanism and durability benefiting from the combination of UHPC and GFRP, and only minimal construction process was needed. The flexural properties of the novel composite plate, varying in centroid height of GFRP grid and loading shear span ratio, were investigated via four-point loading tests. The failure mode, load-deflection curve, sectional strain and ductility of the composite plate were analyzed. Experimental results showed that the flexural failure process of the composite plate could be divided into three stages: elastic stage, working stage with cracks and descent stage. The flexural failure of the composite plate was characterized by the tensile fracture of GFRP grid. The flexural bearing capacity and stiffness of the composite plate can be significantly improved, since the GRFP grid was more completely tensioned as the centroid of the embedded GFRP grid framework fell. The maximum bearing capacity of composite plates could reach 317.9 kN when the distance between GFRP grid and the plate bottom was 25 mm and the shear span ratio was 1.5. Shear failure was only observed in the composite plate with the distance between GFRP grid and the plate bottom of 0 mm and the shear span ratio of 1.5. Finite element (FE) models were established considering both geometric and material nonlinearities to further analyze the flexural failure mechanism of the composite plate. The reliable connection between GFRP grid and UHPC without additional shear connector was proved, and the numerical results coincided well with the experimental ones. Finally, the calculation method introducing the stress distribution non-uniformity coefficient of the GFRP grid plate was proposed to predict the flexural capacity of the composite plate.

Owing to its high electrical conductivity, unique layered structure, and strong hydrophilicity, two-dimensional nanomaterial titanium carbide (Ti3C2Tx) has attracted considerable attention as an electrode material for energy storage systems (EESs). However, the applications of Ti3C2Tx in EESs are severely limited by self-restacking and −F surface terminations, which are usually inevitable during the preparation of Ti3C2Tx.To improve the electrochemical performance of Ti3C2Tx, the present authors doped Ti3C2Tx with nitrogen, preparing N–Ti3C2Tx, via thermal decomposition of urea. The interlayer spacing increased from 1.17 nm in Ti3C2Tx to 1.33 nm in N–Ti3C2Tx and the −F surface termination was largely reduced. Benefiting from the synergistic effect of modified surface termination and expanded interlayer spacing, the prepared N–Ti3C2Tx electrode in 1 M H2SO4 delivers a high specific capacitance (390 F g–1) at a current density of 1 A g–1 (approximately twice that of pristine Ti3C2Tx). To demonstrate the effectiveness of the method in other EESs, the Zn2+-storage capacity of the N–Ti3C2Tx electrode was tested in 1 M ZnSO4. The electrode exhibited a capacitance of 252 F g–1 at 1 A g–1, exceeding that of the pristine Ti3C2Tx electrode (212 F g–1). Furthermore, the energy and power densities of the N–Ti3C2Tx // MnO2–CNT system reached 26 W h kg–1 and 950 W kg–1, respectively, much larger than those of the Ti3C2Tx // MnO2–CNT system (13 W h kg–1 and 550 W kg–1, respectively). The proposed strategy can facilely functionalize Ti3C2Tx for use in different high-performing EESs. [ABSTRACT FROM AUTHOR]

Interplay between the outer steel tubes and the core concrete provides an important guarantee for the superior performance of concrete-filled steel tube (CFST) columns compared to that of reinforced concrete columns. In order to optimize the construction of the large-size non-studded CFST columns in an on-going practical project, the strain distributions in the column under construction were measured and tracked, and the law of the strain distributions of the column under construction is revealed. The study finds that the plane section assumption was not applicable to the strain distributions of the column. Nonlinear variations in the strain levels were observed under bi-directional bending of the column. The absence of studs inside the steel tube significantly weakened the interplay of the outer steel tube and the core concrete by means of a significant slip between the concrete and the steel tube at the column corners. The concrete and the steel tube tended to be stressed and deformed independently. Practical suggestions are given for the design and construction of this type of column. The study results are expected to lay a basic and valuable foundation for in-depth investigations on the mechanical behavior of large-size non-studded concrete-filled steel tube columns under construction. [ABSTRACT FROM AUTHOR]

The equation of state of Li2MnO3 under high pressure was obtained by synchrotron radiation X-ray diffraction in a diamond anvil cell at room temperature. The results showed that the high-pressure compression test is stable to the maximum pressure of 28.00 GPa. The bulk elastic modulus derived from the high-pressure synchrotron radiation diffraction data is (106.20±4.20) GPa, and the first derivative of the bulk elastic modulus is 16.92±1.28. In addition, the high voltage electrical transport properties of Li2MnO3 to 21.00 GPa show that the resistance of Li2MnO3 decreases with the increase of pressure, and the resistance changes exponentially and continuously. [ABSTRACT FROM AUTHOR]

Two-dimensional SnSe2 has become more and more attractive due to the excellent electronic, optoelectronic, and thermoelectric properties. However, the study on magnetic properties is rare. Inspired by the recent experimental synthesis of SnSe2 monolayer and Ag-doped SnSe2 thin films, we use the first-principles calculations combined with the nonequilibrium Green's function method to investigate the structural, electronic, magnetic, and spin transport properties of an Ag-doped SnSe2 monolayer. It is found that the doped system exhibits half-metallic ferromagnetism with the energy gap of about 0.5 eV in the spin-down channel. The spin-polarized transport properties based on Ag-doped SnSe2 monolayers show an excellent spin filtering effect and a negative differential resistance effect under a bias voltage. Interestingly, under a temperature gradient, the spin Seebeck effect and the temperature-controlled reverse of spin polarization are also observed. These perfect spin transport properties can be understood from the calculated spin-polarized band structure and the spin-polarized transport spectrum. These studies indicate the potential spintronic and spin caloritronic applications for Ag-doped SnSe2 monolayer. [ABSTRACT FROM AUTHOR]