Catálogo de publicaciones - revistas

<jats:title>Abstract</jats:title> <jats:p>Interfacial energy anisotropy plays an important role in tilted growth of eutectics. However, previous studies mainly focused on the solid-solid interface energy anisotropy, whether the solid-liquid interface energy anisotropy can significantly affect tilted growth of eutectics remains unclear. In this study, a multi-phase field model was employed to investigate both the effects of solid-liquid and solid-solid interfacial energy anisotropies on tilted growth of eutectics. The findings revealed that both the solid-liquid and the solid-solid interfacial energy anisotropies can induce tilted growth of eutectics. The results also demonstrated that when the rotation angle is within the range of 30°~ 60°, the growth of tilted eutectics is governed jointly by the solid-solid and solid-liquid interfacial energy anisotropies; otherwise, it is mainly controlled by the solid-solid interfacial energy anisotropy. Further analysis showed that, the unequal pinning angles at triple points caused by the adjustment of the force balance results in different solute-diffusion rates on both sides of triple points. This will further induce an asymmetrical concentration distribution along the pulling direction near the solidliquid interface and the tilted growth of eutectics. Our findings not only shed light on the formation mechanism of tilted eutectics but also provide theoretical guidance for controlling the microstructure evolution during eutectic solidification.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>With the development of smart grid, the operation and control of power system is realized through power communication network, especially the power production and enterprise management business involve a large amount of sensitive information, and the requirements for data security and real-time transmission are gradually improved. In this paper, a new 9D complex chaotic system with quaternion is proposed for the encryption of smart grid data. Firstly, a new 9D complex chaotic system with quaternion is proposed, and its attractors, bifurcation diagram, complexity, and 0-1 test are analyzed. Secondly, the pseudo-random sequences are generated by the new chaotic system to encrypt power data. Finally, the proposed encryption algorithm is verified with power data and images in the smart grid, which can ensure the encryption security and real-time. The verification results show that the proposed encryption scheme is technically feasible and available for power data and image encryption in smart grid.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The electronic structure of <jats:italic>β</jats:italic>-uranium, which has five nonequivalent atomic sites in its unit cell, is investigated by means of the density functional theory plus Hubbard-<jats:italic>U</jats:italic> correction with <jats:italic>U</jats:italic> from linear response calculation. It was found that the 5<jats:italic>f</jats:italic> electronic correlation in <jats:italic>β</jats:italic>-uranium are moderate. More interesting, their strengths are site selective, depending on the local atomic environment of the present uranium atom. As a consequence, the occupation matrices and partial 5<jats:italic>f</jats:italic> density of states of <jats:italic>β</jats:italic>-uranium manifest site dependence. In addition, the complicate experimental structure of <jats:italic>β</jats:italic>-uranium could be well reproduced within this theoretical framework.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In this paper, the spatial transmission of electromagnetic induced transparency and four wave mixing signals in the photonic bandgap structure are modulated with the adjustable parameters of light fields. The spatial transmission patterns of relevant signals are experimentally investigated with respect to the optical nonlinear Kerr effect occurring in the modulation process. The experimental results reveal the spatial transmission patterns of the probe transmission and the four-wave mixing signals such as focusing, defocusing, shifting and spatial splitting. This study explains how the tunable parameters of light fields and their interactions with each other may regulate the spatial transmission of light fields by changing the refractive index of the medium, which provides a new research perspective and a certain degree of experimental technology support for more efficient all-optical communication.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In this work, the molecular dynamics (MD) simulation was performed to evaluate the nanomechanical properties and plasticity behavior of amorphous nanolaminates. For this purpose, two types of nanolaminates with the composition layers of Cu<jats:sub>50</jats:sub>Zr<jats:sub>50</jats:sub>/Cu<jats:sub>54</jats:sub>Zr<jats:sub>46</jats:sub>/Cu<jats:sub>60</jats:sub>Zr<jats:sub>40</jats:sub> (ABC-type) and Cu<jats:sub>50</jats:sub>Zr<jats:sub>50</jats:sub>/Cu<jats:sub>60</jats:sub>Zr<jats:sub>40</jats:sub> (AC-type) were firstly designed and the mechanical properties were then evaluated through the nanoindentation and tensile loading. The results indicated that the ABC-type nanolaminate exhibited higher strength and resisted the relaxation of stored energy in the holding stage of the indenting process. The Von-Mises strain distribution also showed that the plastic deformation initiated from the indenter/sample connection and gradually continued into the depth of the sample, while the strained regions in the AC-type considerably extended in the width of the sample perpendicular to the indenting force. The tensile loading results demonstrated that the intersection of the interface and free surface is the potential site for the initiation of shear events in both nanolaminates; however, the AC-type showed a sharp strain accumulation in the soft layer (Cu<jats:sub>50</jats:sub>Zr<jats:sub>50</jats:sub>) with the increase in the total strain value. On the other side, the gradual changes in the chemical compositions of layers and slight compositional variations at the interfaces led to more homogeneous plastic deformation in the ABC-type nanolaminate.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>As the lightest two-dimensional material, monolayer borophene exhibits great potential as electrode materials, but it suffers from stability issues in the free-standing form. Here, the striped-borophene and graphene bilayer (sB/Gr) is found to be a high-performance anode material for rechargeable alkali-metal ion batteries. The first-principles results show that all the three alkali-metal atoms, Li, Na, and K, can be strongly adsorbed on sB/Gr with ultra-low diffusion barriers than that on pristine borophene/graphene, indicating good charge-discharge rates. Remarkably, high storage capacities are proposed for LIBs (1880 mA·h/g), NIBs (1648 mA·h/g), and KIBs (470 mA·h/g) with relatively small lattice change rate (&lt;2.9%) in the process of alkali-metal atoms intercalations. Theses intriguing features of sB/Gr make it an excellent choice for batteries.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Chaotic maps are widely used to design pseudo-random sequence generators, chaotic ciphers, and secure communication systems. Nevertheless, the dynamic characteristics of digital chaos in finite-precision domain must be degraded in varying degrees due to the limited calculation accuracy of hardware equipment. To assess the dynamic properties of digital chaos, we designed a periodic cycle location algorithm (PCLA) from a new perspective to analyze the dynamic degradation of digital chaos. PCLA can divide the state-mapping graph of digital chaos into several connected subgraphs for the purpose of locating all fixed points and periodic limit cycles contained in a digital chaotic map. To test the versatility and availability of our proposed algorithm, the periodic distribution and security of 1-D logistic maps and 2-D Baker maps are analyzed in detail. Moreover, this algorithm is helpful to the design of anti-degradation algorithms for digital chaotic dynamics. These related studies can promote the application of chaos in engineering practice.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>To explore the effect of non-uniform polarization on orbital angular momentum (OAM) in anisotropic media, we investigate the evolution of the spiral spectra and OAM densities of non-uniformly polarized vortex (NUPV) beams in uniaxial crystals propagating orthogonal to the optical axis, where the case of uniformly polarized vortex (UPV) beams with left-handed elliptical polarization is also investigated. At the input plane, the NUPV beams present their spiral spectra of <jats:italic>m</jats:italic> concentrated at <jats:italic>m</jats:italic>=<jats:italic>l</jats:italic>±1 rather than <jats:italic>m</jats:italic>=<jats:italic>l</jats:italic>, and reveal the relation between topological charge <jats:italic>l</jats:italic>, mode of spiral spectra <jats:italic>m</jats:italic> and the power weight value <jats:italic>R</jats:italic> <jats:sub> <jats:italic>m</jats:italic> </jats:sub> expressed by $l = \sum\limits_{m = - \infty }^\infty {m{R_m}} $. The relation $l = \sum\limits_{m = - \infty }^\infty {m{R_m}} $ is still satisfied for UPV beams in uniaxially anisotropic crystals, whereas for NUPV beams their relations are no longer valid owing to non-uniform polarization. Furthermore, the analysis indicates that the asymmetrical distribution of power weight of spiral spectra and the non-zero value in the sum of longitudinal OAM densities originate from the initial non-uniform polarization and anisotropy in uniaxial crystals rather than topological charges. In addition, the relation between spiral spectrum and longitudinal OAM density is numerically discussed. This work may provide an avenue for OAM-based communications, optical metrology and imaging by varying the initial non-uniform polarization.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Based on the BL09 terminal of China Spallation Neutron Source (CSNS), single event upset (SEU) cross sections of 14nm fin field-effect transistor (FinFET) and 65nm quad data rate (QDR) static random-access memories (SRAMs) are obtained under different incident directions of neutrons: front, back and side. It is found that, for both technology nodes, the “worst direction” corresponds to the case that neutrons traverse package and metallization before reaching the sensitive volume. The SEU cross section under the “worst direction” is 1.7~4.7 times higher than those under other incident directions. While for multiple-cell upset (MCU) sensitivity, side incidence is the “worst direction”, with the highest MCU ratio. The largest MCU for the 14nm FinFET SRAM involves 8 bits. Monte-Carlo simulations are further performed to reveal the characteristics of neutron induced secondary ions and understand the inner mechanisms.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Optomagnonics have been widely studied for its microwave optical wave hybrid features. In this study, we achieve laser wavelength conversion in an optomagnonical whispering gallery cavity by adjusting the strength of the applied static magnetic field. We demonstrate numerical simulations on a YIG sphere under different cavity quality factors or coupling strength. We find that a high cavity quality factor will not always mean a high cavity excitation field for Gaussian lasers with finite linewidth. But on state-of-the-art, the high cavity quality factor will always means the higher lightwave conversion rate. In addition, we also find that increasing the mode coupling strength is beneficial to the conversion of the laser. Our study provides new insights into the generation of highly precise tunable coherent light.</jats:p>