Iron-Based Layered Perovskite Oxyfluoride Electrocatalyst for Oxygen Evolution: Insights from Crystal Facets with Heteroanionic Coordination.

Mixed-anion compounds have recently attracted attention as solid-state materials that exhibit properties unattainable with those of their single-anion counterparts. However, the use of mixed-anion compounds to control the morphology and engineer the crystal facets of electrocatalysts has been limited because their synthesis method is still immature. This study explored the electrocatalytic properties of a Pb-Fe oxyfluoride, PbFeOF, with a layered perovskite structure for oxygen evolution reaction (OER) and compared its properties in detail with those of a bulk-type cubic three-dimensional (3D) perovskite, PbFeOF.

Efficacy of hard gummy candy chewing in improving masticatory function in Japanese children aged 6-12 years: A clinical trial.

Objectives: Japanese children have been shown to exhibit decreased masticatory function; however, limited evidence is available regarding the efficacy of certain food items in improving this issue. Therefore, this study examined the effects of chewing hard gummy candy on the masticatory function of Japanese children aged 6-12 years.

Methods: The study included 26 participants (10 boys and 16 girls; mean age ± standard error = 9.

UV ozone treatment for oxidization of spiro-OMeTAD hole transport layer.

For practical application of perovskite photovoltaic devices, it is vital to choose an appropriate carrier extraction material with high mobility, high conductivity, and appropriate molecular energy levels. One of the most frequently used hole transport materials, spiro-OMeTAD, is known to show an improvement in its electrical properties after the oxidation reaction. However, this oxidation reaction is generally accomplished by simple atmospheric exposure, often taking one or more nights under atmospheric conditions, and thus the development of a rapid oxidation strategy without the degradation of device performance is strongly required.

Anionic ordering in PbTiOF revisited by nuclear magnetic resonance and density functional theory.

A combination of F magic angle spinning (MAS) nuclear magnetic resonance (NMR) and density functional theory (DFT) were used to study the ordering of F atoms in PbTiOF. This analysis revealed that F atoms predominantly occupy two of the six available inequivalent sites in a ratio of 73 : 27. DFT-based calculations explained the preference of F occupation on these sites and quantitatively reproduced the experimental occupation ratio, independent of the choice of functional.

Negative Thermal Expansion in Fluoroapatite Pb(VO)F Enhanced by the Steric Effect of Pb.

Negative thermal expansion (NTE) is an unusual thermophysical phenomenon and has gained attention as a way of controlling thermal expansion. Here, we report a substantial NTE in fluoroapatite Pb(VO)F in a limited temperature range. The dilatometric study revealed volume shrinkage below 150 K, giving a linear thermal expansion coefficient of α = -44 ppm/K in the temperature range from 140 to 120 K upon heating.

Catalytic Asymmetric Total Synthesis of Exiguolide.

The catalytic asymmetric total synthesis of (-)-exiguolide, a complex 20-membered macrolide embedded with a bis(tetrahydropyran) motif, is reported. The convergent synthesis involves the construction of the C1-C11 tetrahydropyran segment via catalytic asymmetric allylation and Prins cyclization, and the formation of the C12-C21 phosphonate segment via catalytic asymmetric cyclocondensation reaction and Johnson-Claisen rearrangement. The synthesis of 15-epi-exiguolide is also described.

Light Absorption Properties and Electronic Band Structures of Lead-Vanadium Oxyhalide Apatites Pb (VO ) X (X=F, Cl, Br, I).

The Pb-V oxyhalide apatite compounds Pb (VO ) X (X=F, Cl, Br, I) were successfully synthesized using a facile solution method and studied with respect to their structural/optical characteristics and electronic band structures. UV-visible diffuse reflectance spectroscopy, electrochemical analysis and first-principles calculations showed that the synthesized apatites behaved as n-type semiconductors, with absorption bands in the UV-visible region that could be assigned to electron transitions from the valence band to a conduction band formed by hybridized V 3d and Pb 6p orbitals. Among the apatites examined, Pb (VO ) I had the smallest band gap of 2.

Enhanced Negative Thermal Expansion Induced by Simultaneous Charge Transfer and Polar-Nonpolar Transitions.

Negative thermal expansion (NTE) induced by simultaneous mechanisms, that is, charge transfer and polar-nonpolar transitions, was observed for the first time in BiNiFeO (0.25 ≤ ≤ 0.5).

Solar-Driven Photoelectrochemical Water Oxidation over an n-Type Lead-Titanium Oxyfluoride Anode.

Mixed-anion compounds (e.g., oxynitrides and oxysulfides) are potential candidates as photoanodes for visible-light water oxidation, but most of them suffer from oxidative degradation by photogenerated holes, leading to low stability.

Development of Bismuth Ferrite as a Piezoelectric and Multiferroic Material by Cobalt Substitution.

Bismuth ferrite (BiFeO ) is the most widely studied multiferroic material with robust ferroelectricity and antiferromagnetic ordering at room temperature. One of the possible device applications of this material is one that utilizes the ferroelectric/piezoelectric property itself such as ferroelectric memory components, actuators, and so on. Other applications are more challenging and make full use of its multiferroic property to realize novel spintronics and magnetic memory devices, which can be addressed electrically as well as magnetically.

A Stable, Narrow-Gap Oxyfluoride Photocatalyst for Visible-Light Hydrogen Evolution and Carbon Dioxide Reduction.

Mixed anion compounds such as oxynitrides and oxychalcogenides are recognized as potential candidates of visible-light-driven photocatalysts since, as compared with oxygen 2p orbitals, p orbitals of less electronegative anion (e.g., N, S) can form a valence band that has more negative potential.

Synthesis, Crystal Structure, and Optical Properties of Layered Perovskite Scandium Oxychlorides: SrScOCl, SrScOCl, and BaScOCl.

We report the successful synthesis of three new Ruddlesden-Popper-type scandium oxychloride perovskites, SrScOCl, SrScOCl, and BaScOCl, by conventional solid-state reaction. Small single crystals of SrScOCl were obtained by a self-flux method, and the crystal structure was determined to belong to the tetragonal P4/ nmm space group ( a = 4.08066(14) Å, c = 14.

Systematic charge distribution changes in Bi- and Pb-3d transition metal perovskites.

Charge distribution changes in Bi- and Pb-3d transition metal perovskite type oxides were examined by comprehensive precise structural analysis, spectroscopy, and theoretical investigations. The change in the depth of the d level of the transition metal caused the intermetallic charge transfer. A temperature-induced charge-transfer transition in chemically modified BiNiO results in technologically important negative thermal expansion.

A mammalian mirtron miR-1224 promotes tube-formation of human primary endothelial cells by targeting anti-angiogenic factor epsin2.

Angiogenesis, new vessel formation from pre-existing vessels, is a highly conserved event through vertebrates. However, the system for tuning angiogenesis by species-intrinsic factors is totally unknown. miR-1224 is a member of mammal-specific mirtrons, which were identified as non-canonical microRNAs.

A-Site and B-Site Charge Orderings in an s-d Level Controlled Perovskite Oxide PbCoO.

Perovskite PbCoO synthesized at 12 GPa was found to have an unusual charge distribution of PbPbCoCoO with charge orderings in both the A and B sites of perovskite ABO. Comprehensive studies using density functional theory (DFT) calculation, electron diffraction (ED), synchrotron X-ray diffraction (SXRD), neutron powder diffraction (NPD), hard X-ray photoemission spectroscopy (HAXPES), soft X-ray absorption spectroscopy (XAS), and measurements of specific heat as well as magnetic and electrical properties provide evidence of lead ion and cobalt ion charge ordering leading to PbPbCoCoO quadruple perovskite structure. It is shown that the average valence distribution of PbCoO between PbCrO and PbNiO can be stabilized by tuning the energy levels of Pb 6s and transition metal 3d orbitals.

Hydrothermal Synthesis, Structure, and Superconductivity of Simple Cubic Perovskite (BaK)(BiMg)O with T ∼ 30 K.

We have synthesized a new superconducting perovskite bismuth oxide by a facile hydrothermal route at 220 °C. The choice of starting materials, their mixing ratios, and the hydrothermal reaction temperature was crucial for obtaining products with superior superconducting properties. The structure of the powder sample was investigated using laboratory X-ray diffraction, high-resolution synchrotron X-ray diffraction (SXRD) data, and electron diffraction (ED) patterns [transmission electron microscopy (TEM) analysis].

Oral administration of Japanese sake yeast (Saccharomyces cerevisiae sake) promotes non-rapid eye movement sleep in mice via adenosine A receptors.

We have demonstrated previously that Japanese sake yeast improves sleep quality in humans. In the present study, we examined the molecular mechanisms of sake yeast to induce sleep by monitoring locomotor activity, electromyogram and electroencephalogram in mice. Oral administration of Japanese sake yeast (100, 200, and 300 mg kg ) decreased the locomotor activity by 18, 46 and 59% and increased the amount of non-rapid eye movement (NREM) sleep by 1.

High-Temperature Monoclinic Cc Phase with Reduced c/a Ratio in Bi-based Perovskite Compound Bi2ZnTi1-xMnxO6.

Monoclinic phases with Cm, Pm, and Cc space groups are indispensable to understand the high performance of electromechanical properties at the morphotropic phase boundary (MPB) of lead-based perovskite oxides Pb(ZrxTi1-x)O3 (PZT), [Pb(Mg1/3Nb2/3)O3]1-x-(PbTiO3)x (PMN-PT), and [Pb(Zn1/3Nb2/3)O3]1-x-(PbTiO3)x (PZN-PT). Here, a nearly single monoclinic phase with space group Cc was observed in the Bi-based lead-free perovskite compound Bi2ZnTi1-xMnxO6 at x = 0.4.

High-Pressure Polymorph of NaBiO3.

A new high-pressure polymorph of NaBiO3 (hereafter β-NaBiO3) was synthesized under the conditions of 6 GPa and 600 °C. The powder X-ray diffraction pattern of this new phase was indexed with a hexagonal cell of a = 9.968(1) Å and c = 3.

Observation of Anion Order in Pb2Ti4O9F2.

The observation of anion order is indispensable for the investigation of oxyfluorides. However, the negligible contrast between O(2-) and F(-) in both X-ray and neutron diffraction obscures the distinct anion sites for Rietveld refinement. Therefore, the difference in the chemical bonding of M-O(2-) and M-F(-) is the key to determining anion order.

Melting of Pb Charge Glass and Simultaneous Pb-Cr Charge Transfer in PbCrO3 as the Origin of Volume Collapse.

A metal to insulator transition in integer or half integer charge systems can be regarded as crystallization of charges. The insulating state tends to have a glassy nature when randomness or geometrical frustration exists. We report that the charge glass state is realized in a perovskite compound PbCrO3, which has been known for almost 50 years, without any obvious inhomogeneity or triangular arrangement in the charge system.

Japanese sake yeast supplementation improves the quality of sleep: a double-blind randomised controlled clinical trial.

Activation of adenosine A2a receptors in cerebral neurons induces sleep in various mammals. It was previously found that Japanese sake yeast enriched in adenosine analogues activates A2a receptors in vitro and induces sleep in mice. Here it is reported that sake yeast activated A2a receptors in a cultured human cell line and improved human sleep quality in a clinical trial.

Negative thermal expansion induced by intermetallic charge transfer.

Suppression of thermal expansion is of great importance for industry. Negative thermal expansion (NTE) materials which shrink on heating and expand on cooling are therefore attracting keen attention. Here we provide a brief overview of NTE induced by intermetallic charge transfer in A-site ordered double perovskites SaCuFeO and LaCuFe Mn O, as well as in Bi or Ni substituted BiNiO.

Superconducting double perovskite bismuth oxide prepared by a low-temperature hydrothermal reaction.

Perovskite-type structures (ABO3) have received significant attention because of their crystallographic aspects and physical properties, but there has been no clear evidence of a superconductor with a double-perovskite-type structure, whose different elements occupy A and/or B sites in ordered ways. In this report, hydrothermal synthesis at 220 °C produced a new superconductor with an A-site-ordered double perovskite structure, (Na(0.25)K(0.

Spin frustration from cis-edge or -corner sharing metal-centered octahedra.

A new strategy using cis-edge or -corner sharing metal-centered octahedra is described which enables interesting frustrated spin lattices to be targeted. The examination of "CuV2" triangular motifs in the two new compounds [enH2]Cu(H2O)2[V2O2F8] (1) and [Cu(H2O)(2,2'-bpy)]2[V2O2F8] (2) (where enH2 = ethylenediammonium and 2,2'-bpy =2,2'-bipyridyl) reveals that the [VOF4](2-) anions, which exhibit cis structure directing properties, lead to frustrated lattices owing to the competing ferro and antiferromagnetic interactions. There is direct coordination through two cis F(-) ligands (i.