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Abstract: The solid electrolyte Li0.5La0.5TiO3 (LLTO) with high lithium ion conductivity was prepared by the conventional solid-state reaction method, and those LLTO powders were mixed with inactive second phase (Al2O3, MgO, SiO2) to give composites. The microstructure and conductivity properties of the composite are investigated by using X-ray diffraction, scanning electron microscope and AC impedance method. Those prepared LLTO is cubic crystal with superstructure. All conductivities of LLTO-based composites decrease with the addition of Al2O3 or MgO, but the grain boundary conductivity increases with the addition of SiO2. [Copyright &y& Elsevier]

A detailed and systematic investigation on the effect post heat treatment has on the microstructure evolution and the resultant mechanical properties of the wire arc additive manufacturing processed Mg-5.9Gd-2.8Y-0.7Zr alloy is conducted in this work. The microstructure of the as-built sample is composed mainly of fine equiaxed α-Mg grain and Mg24(Gd, Y)5 phase. The solution heat treatment (400°C × 1 h) has relatively little effect on grain size, but it can effectively reduce the content of the Mg24(Gd, Y)5 phase, which leads to a significantly improved elongation with slightly decreased strength. Further ageing heat treatment at 200°C induces prismatic β' precipitates formation and does not influence other phases and grain size. The samples directly following the peak ageing heat treatment process demonstrate the best tensile properties with yield strength of 227 ± 9 MPa, ultimate tensile strength of 350 ± 4 MPa and elongation of 5.5 ± 0.6%. [ABSTRACT FROM AUTHOR]

It is important to improve the comprehensive performance of the ductile iron bars (DIBs) for the cylinder block of the extra high pressure hydraulic plunger pump and accelerate the industrial application. In this work, the LZQT600-3 DIBs with the diameter of 145 mm were prepared by the horizontal continuous casting (HCC) process, that is, LZQT600-3 HCCDIBs. The microstructure and room temperature tensile properties of different sections [left-edge (surface layer), left-1/2R (left half of the radius), and the center of the HCCDIBs] were studied. The results show that the spheroidization of LZQT600-3 HCCDIBs matrix from the left-edge, left1/2R to the center is at nodulizing grade II and above. As the cooling rate gradually decreases from surface to the center of the HCCIBs, the number of spheroidized graphite is gradually reduced, the size is gradually increased, the shape factor is decreased, and the pearlite content and lamellate spacing are increased. Along the horizontal direction of the section, the hardness of the material is distributed symmetrically around the center of the HCCDIBs. In the vertical direction, the hardness distribution in the center of the HCCDIBs is asymmetrical due to the gravity during the solidification process. Therefore, the microstructure in the lower part of the section solidifies relatively quickly. The left-edge has the best tensile mechanical properties, and the ultimate tensile strength, yield tensile strength and elongation are 597.3 MPa, 418.5 MPa and 9.6%, respectively. The tensile fracture belongs to the ductile-brittle hybrid fracture. The comprehensive performances of LZQT600-3 HCCDIBs meet the actual application requirements of ultra-high pressure hydraulic plunger pump cylinder. [ABSTRACT FROM AUTHOR]

Based on wire arc additive manufacturing (WAAM) technology, AZ31 magnesium alloy in bulk was successfully fabricated, and its microstructure as well as mechanical properties in different planes were observed and analyzed. The AZ31 magnesium alloy has a similar microstructure in the building direction (Z) and travel direction (X), both of which are equiaxed grains. There are heat-affected zones (HAZs) with coarse grains below the fusion line. The second phase is primarily composed of the Mg17Al12 phase, which is evenly distributed in different directions. In addition, the residual stress varies in different directions. There is no significant difference in the hardness of the AZ31 alloy along the Z and X directions, with the average hardness being 68.4 HV and 67.9 HV, respectively. Even though the specimens’ ultimate tensile strength along the travel direction is higher in comparison to that along the building direction, their differences in elongation and yield strength are smaller, indicating that the anisotropy of the mechanical properties of the material is small. [ABSTRACT FROM AUTHOR]

The yield and quality of the medicinal plant Achyranthes bidentata can be increased when it is replanted into a field cultivated previously with the same crop, however, fundamental aspects of its biology (so-called "replanting benefit") still remain to be elucidated. miRNAs are sRNA molecules involved in the post-transcriptional regulation of gene expression in plant biological processes. Here, 267 conserved and 36 novel miRNAs were identified in A. bidentata roots. We compared the miRNA content of the roots (R1) from first-year planting with that of the roots (R2) of second-year replanting, and screened 21 differentially expressed (DE) miRNAs. Based on in silico functional analysis, integrated miRNA-mRNA datasets allowed the identification of 10 miRNA-target family modules, which might participate in the benefit. The expression profiles of the miRNA-target modules were potentially correlated with the presence of the replanting benefit. The indication was that the miRNA-responsive continuous monoculture could reprogram miRNA-mRNA expression patterns, which possibly promote the root growth and development, enhance its transport activity and strengthen its tolerance to various stresses, thereby improving A. bidentata productivity as observed in the replanting benefit. Our study provides basic data for further research on the molecular mechanisms of the benefit in A. bidentata. [ABSTRACT FROM AUTHOR]