Atomically dispersed hexavalent iridium oxide from MnO reduction for oxygen evolution catalysis.

Hexavalent iridium (Ir) oxide is predicted to be more active and stable than any other iridium oxide for the oxygen evolution reaction in acid; however, its experimental realization remains challenging. In this work, we report the synthesis, characterization, and application of atomically dispersed Ir oxide (Ir-) for proton exchange membrane (PEM) water electrolysis. The Ir- was synthesized by oxidatively substituting the ligands of potassium hexachloroiridate(IV) (KIrCl) with manganese oxide (MnO).

Development of serial X-ray fluorescence holography for radiation-sensitive protein crystals.

X-ray fluorescence holography (XFH) is a powerful atomic resolution technique capable of directly imaging the local atomic structure around atoms of a target element within a material. Although it is theoretically possible to use XFH to study the local structures of metal clusters in large protein crystals, the experiment has proven difficult to perform, especially on radiation-sensitive proteins. Here, the development of serial X-ray fluorescence holography to allow the direct recording of hologram patterns before the onset of radiation damage is reported.

Application of High-Energy-Resolution X-ray Absorption Spectroscopy at the U L-Edge to Assess the U(V) Electronic Structure in FeUO.

FeUO was studied to clarify the electronic structure of U(V) in a metal monouranate compound. We obtained the peak splitting of spectra utilizing high-energy-resolution fluorescence detection-X-ray absorption near-edge structure (HERFD-XANES) spectroscopy at the U L-edge, which is a novel technique in uranium(V) monouranate compounds. Theoretical calculations revealed that the peak splitting was caused by splitting of the 6d orbital of U(V) in FeUO, which would be used to detect minor U(V) species.

Regional Antimicrobial Stewardship Program in a Provincial Medical Zone in Japan: a Multifaceted Approach.

Antimicrobial resistance (AMR) is a threat to patient health. However, data to optimize antimicrobial use are limited. Furthermore, reducing antibiotic use raises concerns regarding patient safety.

Tilting and rotational motions of silver halide crystal with diffracted X-ray blinking.

The dynamic properties of crystalline materials are important for understanding their local environment or individual single-grain motions. A new time-resolved observation method is required for use in many fields of investigation. Here, we developed in situ diffracted X-ray blinking to monitor high-resolution diffraction patterns from single-crystal grains with a 50 ms time resolution.

Microtubule-organizing center-mediated structural atypia in low- and high-grade urothelial carcinoma.

Urothelial carcinoma (UC) comprises two subtypes, low grade (LG-UC) and high grade (HG-UC), with different pathological and clinical behavior. LG-UC and HG-UC are classified based on cellular and structural atypia of pathological findings. The mechanisms responsible for maintaining structural atypia, such as the disturbance of nuclear polarity, remain unclear.

Emergence of a new valence-ordered structure and collapse of the magnetic order under high pressure in EuPtP.

The layered hexagonal EuPtP is a rare substance that exhibits two successive valence transitions occurring simultaneously with valence ordering transitions and an antiferromagnetic order. Anticipating that the application of pressure to this sample would induce a new valence-ordered structure and/or a new phenomenon associated with valence fluctuation, we examined the electrical resistivity ρ, the Eu L-edge x-ray absorption spectroscopy, and the powder x-ray diffraction under high pressure. We found a new valence transition at around P  =  2.

Pressure-Driven Spin Crossover Involving Polyhedral Transformation in Layered Perovskite Cobalt Oxyfluoride.

We report a novel pressure-driven spin crossover in layered cobalt oxyfluoride SrCoOF with a distorted CoO square pyramid loosely bound with a fluoride ion. Upon increasing pressure, the spin state of the Co(III) cation gradually changes from a high spin state (S = 2) to a low spin state (S = 0) accompanied by a anomalously large volume contraction (bulk modulus, 76.8(5) GPa).

Mapping platinum species in polymer electrolyte fuel cells by spatially resolved XAFS techniques.

There is limited information on the mechanism for platinum oxidation and dissolution in Pt/C cathode catalyst layers of polymer electrolyte fuel cells (PEFCs) under the operating conditions though these issues should be uncovered for the development of next-generation PEFCs. Pt species in Pt/C cathode catalyst layers are mapped by a XAFS (X-ray absorption fine structure) method and by a quick-XAFS(QXAFS) method. Information on the site-preferential oxidation and leaching of Pt cathode nanoparticles around the cathode boundary and the micro-crack in degraded PEFCs is provided, which is relevant to the origin and mechanism of PEFC degradation.

Visualization of the heterogeneity of cerium oxidation states in single Pt/Ce₂Zr₂O(x) catalyst particles by nano-XAFS.

The cerium oxidation states in single catalyst particles of Pt/Ce2Zr2O(x) (x=7 to 8) were investigated by spatially resolved nano X-ray absorption fine structure (nano-XAFS) using an X-ray nanobeam. Differences in the distribution of the Ce oxidation states between Pt/Ce2Zr2O(x) single particles of different oxygen compositions x were visualized in the obtained two-dimensional X-ray fluorescent (XRF) mapping images and the Ce L(III)-edge nano X-ray absorption near-edge structure (nano-XANES) spectra.

Glitch-free X-ray absorption spectrum under high pressure obtained using nano-polycrystalline diamond anvils.

Nano-polycrystalline diamond (NPD) [Irifune et al. (2003), Nature (London), 421, 599] has been used to obtain a glitch-free X-ray absorption spectrum under high pressure. In the case of conventional single-crystal diamond (SCD) anvils, glitches owing to Bragg diffraction from the anvils are superimposed on X-ray absorption spectra.

Resonant inelastic x-ray scattering of CeB6 at the Ce L(1)- and L(3)-edges.

We report a resonant inelastic x-ray scattering (RIXS) study of crystalline CeB(6). Ce L(α1,2) RIXS was measured with excitation energies resonant with the Ce L(3)-edge. A lifetime-broadening suppressed x-ray absorption near-edge structure (LBS-XANES), which successfully reproduced the L(α1,2) RIXS spectra over wide ranges of excitation and emission energies, was simulated using the SIM-RIXS program.

Measurement of a pauli and orbital paramagnetic state in bulk gold using x-ray magnetic circular dichroism spectroscopy.

We show that bulk gold (Au) exhibits temperature-independent paramagnetism in an external magnetic field by x-ray magnetic circular dichroism spectroscopy at the Au L(2) and L(3) edges. Using the sum-rule analysis, we obtained a magnetic moment of 1.3 × 10(-4) μB/atom in an external magnetic field of 10 T and a paramagnetic susceptibility of 8.

Symmetry of valence states of Heusler compounds explored by linear dichroism in hard-x-ray photoelectron spectroscopy.

This study reports on the linear dichroism in angular-resolved photoemission from the valence band of the Heusler compounds NiTi0.9Sc0.1Sn and NiMnSb.

Colossal negative thermal expansion in BiNiO3 induced by intermetallic charge transfer.

The unusual property of negative thermal expansion is of fundamental interest and may be used to fabricate composites with zero or other controlled thermal expansion values. Here we report that colossal negative thermal expansion (defined as linear expansion <-10(-4) K(-1) over a temperature range ~100 K) is accessible in perovskite oxides showing charge-transfer transitions. BiNiO(3) shows a 2.

Chemical effects of CeL(gamma4) emission spectra for Ce compounds.

High-resolution CeL(gamma4) emission spectra of CeF(3), Ce(2)S(3), CeF(4), and CeO(2) have been measured using a multicrystal, multidetector spectrometer. The spectra exhibited substantial differences depending on the chemical environment of the Ce ions. By comparing the observed CeO(2) spectrum with the band calculations, we determined that the observed chemical effects of the main emission line were primarily attributable to the transitions of the Ce5p band; the high-energy tail at around 6.

Chronic administration of Eucommia leaf stimulates metabolic function of rats across several organs.

Eucommia bark (Eucommia ulmoides Oliver) has been used as an herbal medicine, and more recently, the plant's leaves have been widely used to prepare tea which may have anti-obesity properties. We used a metabolic syndrome-like rat model, produced by feeding a 35% high-fat diet (HFD), to examine potential anti-obesity and anti-metabolic syndrome effects and mechanisms of chronic administration of Eucommia leaf as an extract or green leaf powder. Eighty rats were studied for 3 months in ten groups.

Effects of Eucommia leaf extracts on autonomic nerves, body temperature, lipolysis, food intake, and body weight.

Eucommia ulmoides Oliver leaf extracts (ELE) have been shown to exert a hypolipidemic effect in hamsters. Therefore, it was hypothesized that ELE might affect lipid metabolism via changes in autonomic nerve activities and causes changes in thermogenesis and body weight. We examined this hypothesis, and found that intraduodenal (ID) injection of ELE elevated epididymal white adipose tissue sympathetic nerve activity (WAT-SNA) and interscapular brown adipose tissue sympathetic nerve activity (BAT-SNA) in urethane-anesthetized rats and elevated the plasma concentration of free fatty acids (FFA) (a marker of lipolysis) and body temperature (BT) (a marker of thermogenesis) in conscious rats.

Ameliorative effect of Eucommia ulmoides Oliv. leaves extract (ELE) on insulin resistance and abnormal perivascular innervation in fructose-drinking rats.

Aim Of The Study: Eucommia ulmoides Oliv. leaf is a traditional Chinese medicine that exhibits an anti-diabetic action. This study was designed to investigate whether long-term administration of Eucommia ulmoides Oliv.

X-ray magnetic spectroscopy at high pressure: performance of SPring-8 BL39XU.

An X-ray magnetic circular dichroism experiment under multiple extreme conditions, 2 View Article and Find Full Text PDF

Origin of the X-ray magnetic circular dichroism at the L-edges of the rare-earths in RxR(1-x)'Al2 systems.

An X-ray magnetic circular dichroism (XMCD) study performed at the rare-earth L(2,3)-edges in the R(x)R(1-x)'Al(2) compounds is presented. It is shown that both R and R' atoms contribute to the XMCD recorded at the L-edges of the selected rare-earth, either R or R'. The amplitude of the XMCD signal is not directly correlated to the magnetization or to the value of the individual (R, R') magnetic moments, but it is related to the molecular field acting on the rare-earth tuned in the photoabsorption process.

Probe for spin- and valence-selective X-ray absorption fine structure spectroscopy: EuLgamma4 emission.

EuLgamma(4) emission spectra of EuS, EuF(3), EuCl(3), and Eu(2)O(3) were measured using a multicrystal, multidetector spectrometer. Splitting of the EuLgamma(4) band was observed in the EuS spectra and attributed to exchange interactions between Eu5p and Eu4f. It was shown that because of this splitting, the EuLgamma(4) emission could be used for performing spin-selective measurements.

CaFeO2: a new type of layered structure with iron in a distorted square planar coordination.

CaFeO(2), a material exhibiting an unprecedented layered structure containing 3d(6) iron in a high-spin distorted square-planar coordination, is reported. The new phase, obtained through a low-temperature reduction procedure using calcium hydride, has been characterized through powder neutron diffraction, synchrotron X-ray diffraction, Mossbauer spectroscopy, XAS experiments as well as first-principles DFT calculations. The XAS spectra near the Fe-K edge for the whole solid solution (Sr(1-x)Ca(x))FeO(2) supports that iron is in a square-planar coordination for 0 View Article and Find Full Text PDF