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We compared the cutoff depth of seismicity in and around the Nojima fault broken by the 1995 Kobe earthquake occurring in intraplate Japan with the brittle–ductile transition depth of the widely accepted strength profile model of the crust. We successfully determined the temperature profile from borehole measurements, since almost the same geothermal gradients were observed at two boreholes located about 4 km apart from each other, and the thermal conductivity and heat production were also measured by taking numerous core samples. We found that the cutoff depth was much deeper than the transition depth under the assumption that wet granite is deformed at a strain rate of 3×10−15 s−1. This small strain rate implies, however, that plastic flow is uniformly distributed below the seismogenic region. When the strain rate is assumed to be greater than 10−13 s−1, the cutoff depth can be attributed to the transition depth. This suggests that deformation is localized in a narrow fault zone below the seismogenic region, even in the intraplate region. [Copyright &y& Elsevier]

Early transition metal-based intermetallic compounds, such as ZrV 2 , ZrMn 2 , and ZrCr 2 , can reversibly absorb large amounts of hydrogen and are of great interest for hydrogen storage. The dissociative hydrogen chemisorption can proceed easily on the surface, allowing the rapid formation of intermetallic hydrides. In this study, we present the results of initial NH 3 activity tests conducted on various Zr-based AB 2 -type intermetallic compounds, free of precious transition metals and rare earth metals. A dissociative hydrogen chemisorption together with nitrogen storage proceeds on AB 2 -type Laves phase intermetallic compounds accompanied by a lattice expansion. The formed intermetallic nitride hydride ZrCr 2 N 0.4 H 1.4 exhibits stable catalytic activity as an ammonia synthesis catalyst. In this study, we found a dissociative hydrogen chemisorption together with nitrogen storage proceed on AB 2 -type Laves phase intermetallic compounds, allowing the rapid formation of intermetallic nitride hydrides. The cell volume expansion upon hydrogenation facilitates nitrogen adsorption and dissociation. The formed intermetallic nitride hydride ZrCr 2 N 0.4 H 1.4 exhibits stable catalytic activity as an ammonia synthesis catalyst. [Display omitted] • A hydrogen adsorption together with nitrogen storage in Laves phase intermetallic compounds. • The lattice expansion accompanied by H intercalation could help the insertion of N. • The formed intermetallic nitride hydride exhibits stable catalytic activity for ammonia synthesis. [ABSTRACT FROM AUTHOR]

Abstract: To elucidate the Li+ extraction and insertion mechanism for Li2FeSiO4 nanoparticles, at the atomic scale, X-ray absorption spectroscopy (XAS) measurements at Fe and Si K-edges were performed. Fe K-edge XAS spectra suggest irreversible changes occurring in the local and electronic environment of iron which can be attributable to the characteristic shift in potential plateau during initial cycling of Li2− x FeSiO4 system. While the local environment around Fe atoms significantly changes upon initial cycling, the local Si O environment is mostly maintained. [Copyright &y& Elsevier]

Highlights: [•] LaPd2Sb2, a new superconductor with CaBe2Ge2 type structure is reported. [•] LaPd2Sb2 is a type-II bulk superconductor below 1.4K. [•] The DOS indicates maximum contribution to the Fermi level is from Pd 4d states. [•] LaPd2Sb2 is the first known superconductor in the APd2Sb2 (A=Sr,Ba,RE) system. [ABSTRACT FROM AUTHOR]

Abstract: A series of copper(II) solvatochromic complexes [Cu(acac)(N^N)(ligand)]BPh4 (acac=acetylacetonato; N^N =1,10-phenanthoroline (1), 2,2′-bipyridyl (2); ligand=HMPA, pyridine, DMSO, DMF, MeOH, acetone, and MeCN) have been synthesized and their coordination geometries were crystallographically investigated. The solvent-coordinated cations, adopting a five-coordinate square-pyramidal structure, formed head-to-tail dimers via π⋯π interactions. Solid-state absorption studies revealed that their d–d transition energies are correlated with the donor number of the axial ligands. A linear correlation was found between the d–d transition energies and the Cu–O (axial ligands) distances in the solid-state, revealing the role of the coordination environment on the d–d transition energies in the copper(II) solvatochromic complexes. [Copyright &y& Elsevier]

Abstract: Co-substituted manganese oxide nanosheets, (Mn1−x Co x )O2 have been synthesized in the form of a colloidal suspension via a simple one-pot method. Substitution effects on the structural, optical absorption, and magnetic properties are investigated for the nanosheets and their lamellar aggregates. The composition of the (Mn1−x Co x )O2 nanosheets can be controlled continuously by adjusting the molar ratio of the starting materials. The solubility limit is x ∼0.20 based on the cell volume. In the 0.00≤ x ≤0.20 range, the band gap energy, magnetic moment, and Weiss temperature change systematically with x. The charge density of the (Mn,Co)O2 layer is independent of x (i.e., [(Mn,Co)O2]0.2−) and the cobalt ions are trivalent in low-spin state. [Copyright &y& Elsevier]

Methane, n-hexane, benzene, and cyclopentadiene were decomposed at a relatively mild temperature (773 K) over a Ni catalyst supported on either vapor grown carbon fibers (VGCF) or graphitized carbon fibers (GCF). Transmission electron microscopy showed that the morphology of the fibers changed according to hydrocarbon and particle size. Decomposition of methane and n-hexane produced fishbone-type fibers. The fibers from n-hexane sometimes showed intermittent hollow structures but the diameters of the fibers were widely distributed. Decomposition of benzene and cyclopentadiene mainly produced winding type carbon nanotubes of relatively uniform diameters (10–20 nm). Bidirectional fishbone-type fibers (fibers growing outward from a central catalyst particle) were also observed as a by-product. Small Ni particles (10–20 nm) with stretched tails were present on the tips of tubular fibers, some of which frequently changed growth direction. The varying tubular morphologies can be ascribed to liquid-like Ni particles resulting from the freezing point depression due to a fast dissolution of carbons during decomposition of benzene or cyclopentadiene. The formation of bidirectional fibers was also observed in the decomposition of n-hexane. Relatively large well-faceted Ni particles (diameter 50–110 nm) grew bidirectional fibers. [Copyright &y& Elsevier]