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The intertwining between spin, charge, and lattice degrees of freedom can give rise to unusual macroscopic quantum states, including high-temperature superconductivity and quantum anomalous Hall effects. Recently, a charge density wave (CDW) has been observed in the kagome antiferromagnet FeGe, indicative of possible intertwining physics. An outstanding question is that whether magnetic correlation is fundamental for the spontaneous spatial symmetry breaking orders. Here, utilizing elastic and high-resolution inelastic x-ray scattering, we observe a c-axis superlattice vector that coexists with the 2 × 2 × 1 CDW vectors in the kagome plane. Most interestingly, between the magnetic and CDW transition temperatures, the phonon dynamical structure factor shows a giant phonon-energy hardening and a substantial phonon linewidth broadening near the c-axis wavevectors, both signaling the spin-phonon coupling. By first principles and model calculations, we show that both the static spin polarization and dynamic spin excitations intertwine with the phonon to drive the spatial symmetry breaking in FeGe. The interplay between magnetism and charge density wave in the kagome magnet FeGe is under debate. By using elastic and inelastic X-ray scattering, angle-resolved photoemission spectroscopy, and first principles calculations, Miao et al. propose that the charge density wave is stabilized by spin-phonon coupling. [ABSTRACT FROM AUTHOR]

Topological semimetals are a frontier of quantum materials. In multiband electronic systems, topological band crossings can form closed curves, known as nodal lines. In the presence of spin–orbit coupling and/or symmetry-breaking operations, topological nodal lines can break into Dirac/Weyl nodes and give rise to interesting transport properties, such as the chiral anomaly and giant anomalous Hall effect. Recently, the time-reversal symmetry-breaking induced Weyl fermions are observed in a kagome-metal Co3Sn2S2, triggering interests in nodal-line excitations in multiband kagome systems. Here, using first-principles calculations and symmetry-based indicator theories, we find six endless nodal lines along the stacking direction of kagome layers and two nodal rings in the kagome plane in nonmagnetic Ni3In2S2. The linear dipsersive electronic structure, confirmed by angle-resolved photoemission spectroscopy, induces large magnetoresistance up to 2000% at 9 T. Our results establish a diverse topological landscape of multiband kagome metals. [ABSTRACT FROM AUTHOR]

The topological optimization technique is an effective way to provide the optimal design for the polymeric stents. Conventional topology optimization procedure for polymeric stent was all based on classical theory of elasticity and usually only used one layer of shell element in structural analysis. It will lead to that the simulated stent structural stiffness deviates from the real case. Thus, a novel 3D topology optimization procedure based on Cosserat theory is proposed to maximize the radial stiffness of polymeric stent by taking advantage of the size effect of polymer materials. The stent structural analysis is implemented by a proposed high-order Cosserat spectral element method, ensuring that the analysis and optimization results can achieve high accuracy with only one layer of element for the polymeric stent. Cosserat characteristic length of polymeric material is obtained by the three-point bending test, and a parametric analysis is conducted to identify the effect of Cosserat characteristic length, volume fraction, and unit cell size on the optimized stent structure, and the optimal results based on the Cosserat theory are compared with the conventional ones. It is found that the size effect has a significant impact on the topology optimization results of polymeric stent. Compared with conventional commercial stent, the optimal polymeric stent obtained by the Cosserat theory has lower volume fraction and higher radial stiffness. Our results provide an effective way to further improve the mechanical performance of the polymeric stent. [ABSTRACT FROM AUTHOR]

Let q ≥ 3 be a positive integer, and let D = { 0 , a , b } with gcd (a , b) = 1 . For the self-similar measure μ q , D which is generated by the iterated function system { τ d (x) = x + d q } d ∈ D , it is well known that if q is divisible by 3 and { a , b } ≡ { 1 , 2 } (mod 3) , μ q , D is a spectral measure with a spectrum Λ (q , C) = { ∑ j = 0 n q j a j : a j ∈ C = { 0 , q / 3 , 2 q / 3 } and n ∈ N }. In this paper, we study some positive integers p such that p Λ (q , C) is also a spectrum of μ q , D . [ABSTRACT FROM AUTHOR]

A Legendre polynomial-based stochastic micromechanical framework is proposed to quantify the unbiased probabilistic behavior for the unsaturated concrete repaired by the electrochemical deposition method (EDM). By following the authors' previous works, a deterministic micromechanical model with new multilevel homogenization scheme for the repaired unsaturated concrete is presented based on the material's microstructures. With the stochastic descriptions for the microstructures of the repaired unsaturated concrete, the deterministic framework is extended to stochastic. The unbiased probabilistic behavior of the repaired concrete is reached by incorporating the Legendre polynomial approximations and the Monte Carlo simulations. The predictions herein are then compared with the available experimental data, existing models and the commonly used probability density functions, which indicate that the presented stochastic micromechanical framework is capable of characterizing the EDM healing process for unsaturated concrete considering the material's random microstructure. Finally, the statistical effects of the deposition products and unsaturated pores are discussed. [ABSTRACT FROM AUTHOR]

AIDS/HIV is a serious life-threatening and public health problem that urges for new antiviral drugs to control. A bis-indole alkaloid voacamine has been isolated from Voacanga africana Stapf. In this study, voacamine 1H and 13C chemical shift assignments were redetermined using 1D and 2D NMR; 1H NMR and 13C NMR chemical shifts were accurately assigned. Absolute configuration was confirmed by single-crystal X-ray diffraction analysis with Cu Kα radiation, and in vitro antiviral activity against HIV via effecting the binding affinity with gp120 based on SPRi experiment was testified. This study supports the potential value of voacamine as a natural agent against AIDS/HIV. [ABSTRACT FROM AUTHOR]

In this study, yttria-stabilized zirconia (YSZ) nanoparticles with a core-shell structure (YSZ@Ni) were used to produce a YSZ/metal thermal barrier coating by the laser cladding process. The surface morphology, phase composition, and elemental distribution of the cladding layer were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive spectroscopy (EDS), respectively. Splashing of YSZ nanoparticles during the cladding process was reduced when they were encapsulated with nickel. It was found that primary phases of elliptically shaped YSZ and YSZ/(FeCr2O4) eutectic nanostructures formed in the center of the molten pool, whereas equiaxed YSZ crystals formed along the edges after the laser cladding. The results showed that aggregation of Ni was observed in the interlayer between the ceramic coating and the substrate. Ni-rich spheres were observed around the equiaxed YSZ crystals. Furthermore, the solidification behavior of YSZ@Ni core-shell nanoparticles was analyzed by studying the thermodynamics and kinetics. [ABSTRACT FROM AUTHOR]

New 7xxx aluminum alloys with high alloying contents are being designed, which could induce serious hot tearing defects during direct-chill (DC) casting. Among all factors affecting hot tearing of 7xxx alloys, undoubtedly alloying elements play a significant role. In this study, the effect of main alloying elements (Zn, Mg, and Cu) on hot tearing of grain-refined Al-xZn-yMg-zCu alloys was investigated by a dedicated hot tearing rating apparatus simulating the DC-casting process. It was found that the minimum and maximum hot tearing susceptibilities occur for 4 to 6 and 9 wt pct Zn, respectively, indicating the complicated effect of Zn content. The hot tearing resistance of grain-refined Al-9Zn-yMg-zCu alloys is enhanced with increasing Mg content but is deteriorated with increasing Cu content. This can be attributed to the interaction of the thermal stresses, melt feeding, and final eutectics. The observed tendencies of the main alloying elements on hot tearing were also confirmed for four commercial 7xxx alloys. In addition, both the load value at non-equilibrium solidus and the SKK criterion proposed by Suyitno et al. using measured load developments were found to be good indicators in predicting hot tearing susceptibility. This study can provide a beneficial guide in designing 7xxx alloys considering the potential occurrence of hot cracks beforehand. [ABSTRACT FROM AUTHOR]

Keywords: Tobacco; Cumuliphoma indica; China; Fungal pathogens EN Tobacco Cumuliphoma indica China Fungal pathogens 331 332 2 03/16/23 20230201 NES 230201 Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/s42161-022-01247-3. Tobacco, Cumuliphoma indica, China, Fungal pathogens. [Extracted from the article]

An appropriate experimental scheme and an accurate constitutive model are the two key factors that determine the success or failure of the constitutive equations used to simulate hot deformation behavior during the continuous casting process. In this study, according to the characteristics of the thin-slab continuous casting process, the experimental scheme on hot tensile tests is designed and validated by the analysis of fracture surfaces. Isothermal hot tensile tests were performed on a Gleeble 1500 thermomechanical simulator at four different temperatures (1173 K, 1273 K, 1373 K, and 1473 K) and four different strain rates (10−3, 10−2, 10−1, and 1 s−1). Based on the flow stress obtained from the tensile tests, the Arrhenius-type constitutive equation was established. It is shown that the simulation results are in good agreement with the experimental data. To further understand the constitutive behavior, activation energy maps were also developed in this study. Through a brief analysis of the activation energy map, directions for future work were surmised. [ABSTRACT FROM AUTHOR]

A modified Biot/Squirt flow model was developed. The difference between MBISQ and BISQ models is the expression for the porosity differential. Numerical analysis shows that the acoustic dispersion predicted by MBISQ is much higher than by BISQ. Investigations of the effects of permeability, viscosity, and squirt flow length on velocity and attenuation indicate that the behavior of MBISQ agrees with that of the BISQ model. The result of sediment acoustic inversion based on MBISQ was more reasonable than the result of BISQ model. [ABSTRACT FROM AUTHOR]

A novel binuclear praseodymium(III) complex with N-(2-propionyl)salicyloylhydrazone (C10H10N2O4, H3L) and p-hydroxybenzoic acid (C7H6O3, Phba) was prepared in a H2O-C2H5OH mixed solution, and the crystal structure of [Pr2(H2L)2(Phba)4(H2O)2] · 2H2O ( I) was determined by X-ray single crystal diffractometry. Complex I crystallizes in the monoclinic system, space group P21/ c, a = 1.1050(4), b = 1.9534(7), c = 1.2376(4) Å, β = 94.955(7)°, and Z = 4. In the structure each Pr3+ ion lies in a single capped square antiprism geometry coordinated by carboxyl O and acyl O atoms and azomethine N atom of one ligand (H2L− form), which coordinates via the keto form, four carboxyl O atoms from two Phba, and O atoms of two water molecules. In each molecule, two tridentate ligands were coordinated by the H2L− form, and each Pr3+ ion was chelated by the carboxyl group from Phba. The carboxyl groups of H2L− and other two Phba were coordinated via μ2-bridging form and bidentate bridging form, respectively. Complex I and ligands Phba and H3L were also searched for biological activity against Valsa mali by the growth rate method. The result showed that the inhibitory rate of ligands Phba and H3L is better than complex I, especially Phba. [ABSTRACT FROM AUTHOR]

High power red light was generated from a periodically-poled stoichiometric LiTaO3 (PPSLT) by single-pass frequency doubling of a diode-side-pumped, Q-switched Nd:YAG laser at 1319 nm. An average power of 2.4 W of the 660 nm red light was obtained at the fundamental power of ∼5.4 W with the conversion efficiency up to 44.4% and with low fluctuation down to 2%. The high efficiency and stability at the red output indicate that it is a practical method to construct a reliable compact red laser. [ABSTRACT FROM AUTHOR]

This paper presents results of experimental and analytical investigation on molten alloy drop fragmentation in water pool. Emphasis is directed towards delineating the roles which melt to coolant heat transfer and melt solidification play in the fragmentation process. The strong impact of coolant temperature upon fragmentation process is addressed. A set of 23 drop fragmentation experiments were performed, in which 8 experiments employed a low melting point alloy, cerrobend-70 and 15 experiments using Pb–Bi eutectic alloy as drop fluid. The results show strong impact of coolant temperature on particle size distribution of the fragmented drops. A linear stability analysis of the interface between the two liquid fluids with thin crust growing between them, is performed. A modified dimensionless Aeroelastic number, for Kelvin–Helmholtz instability, is obtained and used as a criteria for fragmentation of molten drops penetrating into another liquid coolant media with lower temperature. The nondimensionalized mean diameter of the fragmented particles is correlated with the Aeroelastic number. [ABSTRACT FROM AUTHOR]

The spinodal decomposition and coarsening reaction of a 45Cu-30Ni-25Fe alloy aged with and without prior 75% cold rolling have been studied by Vickers hardness tester, X-ray diffraction, optical microscope, and scanning and transmission electron microscopes. Spinodal decomposition took place in the alloys aged in the temperature range of 600–950°C without prior deformation, and then spinodal structure in these alloys would coarsen only continuously. Spinodal decomposition and continuous coarsening reaction of spinodal structure took place in the alloys aged at lower temperature with prior deformation. This process was corresponding to recovery of spinodal structure in the deformed alloys. Discontinuous coarsening reaction of spinodal structure would also take place in the alloys aged at higher temperature with prior deformation. This process was corresponding to recrystallization of spinodal structure in the deformed alloys. [ABSTRACT FROM AUTHOR]

A procedure for preparing 3C-SiC/SiO2 composite nanocrystals embedded in Si matrix that emit blue light is reported. Through electrochemical etching of polycrystalline 3C-SiC wafers followed by ultrasonic treatment in water bath, we fabricated luminescent colloidal 3C-SiC nanocrystals. Porous Si samples that have been naturally oxidized in air for 12 h were immersed in agitated aqueous suspension of 3C-SiC nanocrystals for 10 min and then dried in air, followed by annealing in argon atmosphere to form core-shell structured 3C-SiC/SiO2 nanocrystals embedded in Si matrix. Our result shows that the luminescence of 3C-SiC/SiO2 composite nanocrystals is very stable over time or under high temperature. As robust and stable Si-based solid blue-emitters, they have important implications for engineering photonic components in optoelectronics and photonics. [ABSTRACT FROM AUTHOR]

Alloying effects of iridium on the glass formability (GFA) of the Zr-Ir-Cu-Al system have been investigated, and several new bulk metallic glasses (BMGs) with high GFA have been successfully developed. Additions of Ir in the Zr-Cu-Al system can yield a beneficial distribution in atomic sizes, but the strong chemical interaction of the Zr-Ir atomic pair limits the maximum addable Ir contents and the resultant GFA. Our analyses indicate that the optimum composition for alloying elements is determined by not only topological but also chemical factors. Phase competition upon solidification, rather than effects from individual affecting factors, dictates the GFA of BMG systems. [ABSTRACT FROM AUTHOR]

High power red light was generated from a periodically-poled stoichiometric LiTaO3 (PPSLT) by single-pass frequency doubling of a diode-side-pumped, Q-switched Nd:YAG laser at 1319 nm. An average power of 2.4 W of the 660 nm red light was obtained at the fundamental power of ∼5.4 W with the conversion efficiency up to 44.4% and with low fluctuation down to 2%. The high efficiency and stability at the red output indicate that it is a practical method to construct a reliable compact red laser. [ABSTRACT FROM AUTHOR]