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Fe and Ni Kα X‐ray fluorescence holography measurements were conducted on a single crystal Fe65Ni35 Invar alloy at 100 and 300 K to investigate the temperature dependence of the 3‐dimensional local structures around the Fe and Ni atoms, respectively. Local structural information was obtained by detailed analyses using a L1‐regularized linear regression for the experimental data. At 100 K, the local atomic arrangements around both the elements show fcc structures. At 300 K, however, only the image around Fe shows a bcc‐like neighboring arrangement. From these X‐ray fluorescence holography data, we propose a model that with increasing temperature, an Fe atom with the low‐spin state enters at the central position of the fcc lattice and is stabilized. And then, large angular positional fluctuations are induced for the atoms at the face‐centered positions around the central Fe atom only. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abbildung von chiralen Domänen: Resonante zirkular polarisierte Röntgenbeugung wurde verwendet, um zwischen kristallinen Enantiomeren zu unterscheiden (siehe Bild). Die gezielte Steuerung der Penetrationstiefe und der Strahlfokussierung ermöglicht die Visualisierung der dreidimensionalen Morphologie der Chiralitätsdomänen und stellt eine Verbesserung für das Kristall ‐ Engineering dar. [ABSTRACT FROM AUTHOR]

OBJECTIVE Whether patients, who have lost bone mass, can be restored to age-matched control levels by some means is still controversial. We investigated how the thyroid status after antithyroid drug therapy for various periods of time affects bone metabolism in patients with hyperthyroidism by assessing currently used biochemical markers of bone turnover and distal radius bone mineral density (BMD). DESIGN AND PATIENTS The biochemical markers of bone turnover and BMD at the distal one third of the radius were measured in 79 women with hyperthy-roidism treated with antithyroid drugs for various periods of time. The patients were divided into two groups according to thyroid function at the time of study: a hyperthyroid group (serum thyroid stimulating hormone (TSH) < 0.4 mU/l) and an euthyroid group (TSH 0.4–4.0 mU/l). Second, each group was further divided according to the duration of therapy: short-term (less than 3 years ) and long-term (3 or more years). MEASUREMENTS Urinary type I collagen degradation products (CTx) were measured by the CrossLapsTM ELISA kit. Urinary pyridinoline (Pyr) and deoxypyridinoline (Dpyr) were measured by high performance liquid chromatography (HPLC) after acid hydrolysis. Serum N-mid osteocalcin (OCN-mid) was measured by a recently developed enzyme-linked immunosorbent assay. Serum alkaline phosphatase (ALP) was determined by routine laboratory methods. Bone mineral density (BMD) at the distal one third of the radius was measured using dual energy X-ray absorptiometry (DEXA; DCS-600EX, Aloka, Tokyo). RESULTS There were statistically significant positive correlations of FT3 and FT4 with the biochemical markers of bone turnover. There were significant negative correlations between the biochemical markers and BMD only in patients undergoing long-term therapy. In a comparison between hyperthyroid and euthyroid groups based on duration of treatment (long-term and short-term), and in a comparison without regard for... [ABSTRACT FROM AUTHOR]

One of the problems in the construction of a large-scale multiprocessor system is that a long time is required for the data exchange among such system elements as the processor unit and the memory unit, which degrades the efficiency of the whole system. If the data exchange in such a system is performed by electrical wiring, a limit is imposed on the transmission speed and the reliability. From such a viewpoint, we proposed an optical data exchange system suited to high-speed large-capacity communication. The broadcasting optical bus using the cylindrical mirror was developed, and its feasibility was demonstrated by the recently constructed experimental pilot model. This paper presents the design method for the broadcasting optical bus based on the cylindrical mirror and the optical transmitter receivers. Expressions are derived for the optical power distribution on the transmitter receivers and the efficiency of the optical bus. The actual design is shown by an example. [ABSTRACT FROM AUTHOR]

Antiferromagnets and ferrimagnets with a low net magnetic moment are key components for future spintronic devices because they enable high‐integration and high‐speed (on the order of THz) operations. Cr2O3 is one of the few antiferromagnets that can achieve 180° manipulation of its spin by electrical means. In this study, the authors developed a new functional material, Cr2O3, with tunable parasitic magnetization. The authors demonstrate both magnitude and direction tunability of parasitic magnetization in Cr2O3 thin films by doping. A sublattice magnetization reduction and displacement‐induced nonequivalent Cr moments by site‐selective substitution of nonmagnetic elements are inferred to be the origin of the parasitic magnetization. By utilizing the tunable parasitic magnetization, the authors demonstrate the manipulation of antiferromagnetic single domain. In addition, the authors confirm the low‐electric‐field switching ability of the antiferromagnetic spin in a doped Cr2O3/Co exchange coupling system. Such tunable parasitic magnetization enables easy manipulation and detection of antiferromagnetic spin and provides a platform for further understanding of antiferromagnets and research opportunities in innovative spintronics device applications. Tunable parasitic magnetization in magnetoelectric antiferromagnets enables easy manipulation and detection of antiferromagnetic spin and provides a platform for further understanding of antiferromagnets. The tuning in direction and magnitude of parasitic magnetization in Cr2O3 by doping, control of antiferromagnetic single domain state by a magnetic field, and low electric field switching of antiferromagnetic spin are demonstrated. [ABSTRACT FROM AUTHOR]

We present low‐temperature X‐ray fluorescence holography experiments to investigate the atomic scale structure of the high‐temperature superconductor FeSe0.4Te0.6. The results present a direct investigation of the local structure around the Fe atoms. Very clear images of the structure are obtained by a sparse modeling approach to the experimental data using a L1‐regularized linear regression. The results are in good agreement with previous findings of XRD and XAFS experiments on the FeSe1−xTex system, but furthermore indicate large fluctuations in the Fe sub‐lattice. The findings also represent a starting point for further discussions on more curious features of the FeSe1−xTex structure. The atomic scale structure of the high‐temperature superconductor FeSe0.4Te0.6 is investigated by low‐temperature X‐ray fluorescence holography experiments using a sparse modeling approach to the experimental data. The results are in good agreement with previous findings of XRD and XAFS experiments on the FeSe1−xTex system, but furthermore indicate large fluctuations in the Fe sub‐lattice. [ABSTRACT FROM AUTHOR]