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<jats:p>We prepared the semimetals RAlSi (R = light rare earth), and systematically study their crystal structures and magnetic properties. X-ray diffractions confirm the coexistence of the site-disordered phase with group space of <jats:italic>I</jats:italic>4<jats:sub>1</jats:sub>/<jats:italic>amd</jats:italic> and the noncentrosymmetrically ordered phase with space group of <jats:italic>I</jats:italic>4<jats:sub>1</jats:sub> <jats:italic>md</jats:italic> in RAlSi alloy. The ordered phase is the main phase in RAlSi alloy. RAlSi alloys show nonmagnetic character for R = La, low temperature ferromagnetic order for R = Ce, Pr, and paramagnetic character for R = Nd, respectively. SmAlSi shows metamagnetic transition at 10 K and ferromagnetic order at 143 K, respectively. SmAlSi follows the van Vleck paramagnetic model in its paramagnetic region. The magnetization curves of RAlSi (R = Ce, Pr, Sm) follow the mixed model of ferromagnetism and paramagnetism, and the fitted saturation moment <jats:italic>M</jats:italic> <jats:sub>S</jats:sub> depends on the moment of trivalent rare earth. The paramagnetic susceptibility <jats:italic>χ</jats:italic> of RAlSi is going up with increasing the atomic order numbers of rare earth elements. This reveals that the magnetic property of RAlSi originates from the rare earth.</jats:p>

<jats:p>We report an approach to the rapid, one-step, preparation of a variety of wide-bandgap silicon carbide/graphene nanosheet (SiC/GNSs) composites by using a high-density helicon wave plasma (HWP) source. The microstructure and morphology of the SiC/GNSs are characterized by using scanning electron microscopy (SEM), Raman spectroscopy, x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and fluorescence (PL). The nucleation mechanism and the growth model are discussed. The existence of SiC and graphene structure are confirmed by XRD and Raman spectra. The electron excitation temperature is calculated by the intensity ratio method of optical emission spectroscopy. The main peak in the PL test is observed at 420 nm, with a corresponding bandgap of 2.95 eV that indicates the potential for broad application in blue light emission and ultraviolet light emission, field electron emission, and display devices.</jats:p>

<jats:p>Investigation of neoclassical tearing mode and its suppression by electron cyclotron current drive (ECCD) has been carried out in HL-2M tokamak. The current driving capability of the electron cyclotron wave is evaluated. It is found that the deposition location can be effectively controlled by changing the poloidal angle. The validation of electron cyclotron wave heating and current driving has been demonstrated for the upper launcher port. We show that 3.0 MW and 2.5 MW modulated ECCD can completely stabilize (2,1) and (3,2) NTMs, respectively. The non-modulated ECCD, radial misalignment as well as current profile broadening have deleterious effect on the NTM stabilization. The time required for suppression of (3,2) mode is shorter than that required for the suppression of (2,1) mode. Moreover, the time needed for complete stabilization at different initial island width has been quantitatively presented and analyzed.</jats:p>

<jats:p>The core impurity confinement properties are experimentally investigated in the Experimental Advanced Superconducting Tokamak (EAST) plasma heated by lower hybrid wave (LHW) and electron cyclotron resonance heating (ECRH) (LHW+ECRH). It is shown that the impurity confinement time (<jats:italic>τ</jats:italic> <jats:sub>imp</jats:sub>) in the L-mode plasma jointly heated by LHW and ECRH is weakly dependent on electron density but strongly dependent on the heating power, thus it is shorter than that in LHW-only heated L-mode plasma with the similar plasma parameters. The combined heating of LHW and ECRH can reduce the collisionality and indicates a more effective heating method for core <jats:italic>τ</jats:italic> <jats:sub>imp</jats:sub> reduction and normalized poloidal beta (<jats:italic>β</jats:italic> <jats:sub>P</jats:sub>) improvement. It should be emphasized that in this high <jats:italic>β</jats:italic> <jats:sub>P</jats:sub> operation window the small ELM regime can be accessed, and an L-mode level <jats:italic>τ</jats:italic> <jats:sub>imp</jats:sub> (40 ms–80 ms) and high <jats:italic>β</jats:italic> <jats:sub>N</jats:sub> (∼ 1.7) can be obtained simultaneously. It means that this typical small ELMy H-mode regime has an advantage in avoiding the serious tungsten accumulation, and will be competitive in future long-pulse steady-state and high-performance operation with high-Z material plasma-facing components.</jats:p>

<jats:p>The heredity of clusters in rapidly cooled (Zr<jats:sub>50</jats:sub>Cu<jats:sub>50</jats:sub>)<jats:sub>100 – <jats:italic>x</jats:italic> </jats:sub>Al<jats:sub> <jats:italic>x</jats:italic> </jats:sub> melts and its correlation with glass-forming ability (GFA) are studied via molecular dynamics simulations. Pair distribution function and the largest standard cluster (LSC) are adopted to characterize the local atomic structures in the (Zr<jats:sub>50</jats:sub>Cu<jats:sub>50</jats:sub>)<jats:sub>100 – <jats:italic>x</jats:italic> </jats:sub>Al<jats:sub> <jats:italic>x</jats:italic> </jats:sub> systems. The [12/555] icosahedra and their medium-range order (IMRO) play an important role in forming (Zr<jats:sub>50</jats:sub>Cu<jats:sub>50</jats:sub>)<jats:sub>100 – <jats:italic>x</jats:italic> </jats:sub>Al<jats:sub> <jats:italic>x</jats:italic> </jats:sub> metallic glasses (MGs). The fraction of [12/555], the number of IMRO, and the maximum size of IMRO in MGs increase significantly with increasing <jats:italic>x</jats:italic>. A tracking study further reveals that the configuration heredity of icosahedral clusters starts from supercooled liquids. No direct correlation exists between the GFA and the onset temperature of continuous or stated heredity. Instead, a larger hereditary supercooled degree of icosahedra matches with better GFA of Al-doped Zr<jats:sub>50</jats:sub>Cu<jats:sub>50</jats:sub> alloys.</jats:p>

<jats:p>The structure–dynamics correlations in a nonlocal manner were investigated in CuZr metallic glass-forming liquids via classical molecular dynamics simulations. A spatial coarse-graining approach was employed to incorporate the nonlocal structural information of given structural order parameters in the structure–dynamics relationship. It is found that the correlation between structure order parameters and dynamics increases with increasing coarse-graining length and has a characteristic length scale. Moreover, the characteristic correlation length exhibits a non-monotonic temperature evolution as temperature approaches glass transition temperature, which is not sensitive to the considered structure order parameters. Our results unveil a striking change in the structure–dynamics correlation, which involves no fitting theoretical interpretation. These findings provide new insight into the structure–dynamics correlation in glass transition.</jats:p>

<jats:p>It has been a long-standing puzzling problem that some glasses exhibit higher glass transition temperatures (denoting high stability) but lower activation energy for relaxations (denoting low stability). In this paper, the relaxation kinetics of the nanoconfined D-mannitol (DM) glass was studied systematically using a high-precision and high-rate nanocalorimeter. The nanoconfined DM exhibits enhanced thermal stability compared to the free DM. For example, the critical cooling rate for glass formation decreases from 200 K/s to below 1 K/s; the <jats:italic>T</jats:italic> <jats:sub>g</jats:sub> increases by about 20 K–50 K. The relaxation kinetics is analyzed based on the absolute reaction rate theory. It is found that, even though the activation energy <jats:italic>E</jats:italic>* decreases, the activation entropy <jats:italic>S</jats:italic>* decreases much more for the nanoconfined glass that yields a large activation free energy <jats:italic>G</jats:italic>* and higher thermal stability. These results suggest that the activation entropy may provide new insights in understanding the abnormal kinetics of nanoconfined glassy systems.</jats:p>

<jats:p>Using the structure search of particle swarm optimization (PSO) algorithm combined with density functional theory (DFT), we conduct a systematic two-dimensional (2D) material research on the SiO and discover a P2 monolayer structure. The phonon spectrum shows that the 2D P2 is dynamic-stable under ambient pressure. Molecular dynamics simulations show that 2D P2 can still exist stably at a high temperature of 1000 K, indicating that 2D P2 has application potential in high-temperature environments. The intrinsic 2D P2 structure has a quasi-direct band gap of 3.2 eV. The 2D P2 structure can be transformed into a direct band gap semiconductor by appropriate strain, and the band gap can be adjusted to the ideal band gap of 1.2 eV–1.6 eV for photovoltaic materials. These unique properties of the 2D P2 structure make it expected to have potential applications in nanomechanics and nanoelectronics.</jats:p>

<jats:p>An effective regulation of the magnetism and interface of ferromagnetic materials is not only of great scientific significance, but also has an urgent need in modern industry. In this work, by using the first-principles calculations, we demonstrate an effective approach to achieve non-volatile electrical control of ferromagnets, which proves this idea in multiferroic heterostructures of ferromagnetic LaTiO<jats:sub>3</jats:sub> and ferroelectric BiFeO<jats:sub>3</jats:sub>. The results show that the magnetic properties and two-dimensional electron gas concentrations of LaTiO<jats:sub>3</jats:sub> films can be controlled by changing the polarization directions of BiFeO<jats:sub>3</jats:sub>. The destroyed symmetry being introduced by ferroelectric polarization of the system leads to the transfer and reconstruction of the Ti-3d electrons, which is the fundamental reason for the changing of magnetic properties. This multiferroic heterostructures will pave the way for non-volatile electrical control of ferromagnets and have potential applications.</jats:p>

<jats:p>Using the evolutionary methodology for crystal structure prediction, we have predicted the orthorhombic <jats:italic>Cmcm</jats:italic> and <jats:italic>Pnma</jats:italic> phases for ScB<jats:sub>4</jats:sub>. The earlier proposed CrB<jats:sub>4</jats:sub>-, FeB<jats:sub>4</jats:sub>-, MnB<jats:sub>4</jats:sub>-, and ReP<jats:sub>4</jats:sub>-type structures for ScB<jats:sub>4</jats:sub> are excluded. It is first discovered that the <jats:italic>Cmcm</jats:italic> phase transforms to the <jats:italic>Pnma</jats:italic> phase at about 18 GPa. Moreover, both phases are dynamically and mechanically stable. The large bulk modulus, shear modulus, and Young’s modulus of the two phases make it an optimistic low compressible material. Moreover, the strong covalent bonding nature of ScB<jats:sub>4</jats:sub> is confirmed by the ELF analysis. The strong covalent bonding contributes greatly to its stability.</jats:p>