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In an effort to develop a Standard Reference Material (SRM™) for Seebeck coefficient, we have conducted a round-robin measurement survey of two candidate materials--undoped [Bi.sub.2] [Te.sub.3] and Constantan (55 % […]

Web pages have become fundamental in conveying information for companies and individuals, yet designing web page layouts remains a challenging task for inexperienced individuals despite web builders and templates. Visual containment, in which elements are grouped together and placed inside container elements, is an efficient design strategy for organizing elements in a limited display, and is widely implemented in most web page designs. Yet, visual containment has not been explicitly addressed in the research on generating layouts from scratch, which may be due to the lack of hierarchical structure. In this work, we represent such visual containment as a layout tree, and formulate the layout design task as a hierarchical optimization problem. We first estimate the layout tree from a given a set of elements, which is then used to compute tree‐aware energies corresponding to various desirable design properties such as alignment or spacing. Using an optimization approach also allows our method to naturally incorporate user intentions and create an interactive web design application. We obtain a dataset of diverse and popular real‐world web designs to optimize and evaluate various aspects of our method. Experimental results show that our method generates better quality layouts compared to the baseline method. [ABSTRACT FROM AUTHOR]

The interplay among magnetism, electronic nematicity, and superconductivity is the key issue in strongly correlated materials including iron-based, cuprate, and heavy-fermion superconductors. Magnetic fluctuations have been widely discussed as a pairing mechanism of unconventional superconductivity, but recent theory predicts that quantum fluctuations of nematic order may also promote high-temperature superconductivity. This has been studied in FeSe1−xSx superconductors exhibiting nonmagnetic nematic and pressure-induced antiferromagnetic orders, but its abrupt suppression of superconductivity at the nematic end point leaves the nematic-fluctuation driven superconductivity unconfirmed. Here we report on systematic studies of high-pressure phase diagrams up to 8 GPa in high-quality single crystals of FeSe1−xTex. When Te composition x(Te) becomes larger than 0.1, the high-pressure magnetic order disappears, whereas the pressure-induced superconducting dome near the nematic end point is continuously found up to x(Te) ≈ 0.5. In contrast to FeSe1−xSx, enhanced superconductivity in FeSe1−xTex does not correlate with magnetism but with the suppression of nematicity, highlighting the paramount role of nonmagnetic nematic fluctuations for high-temperature superconductivity in this system. Despite studies in FeSe1−xSx, it is yet unconfirmed whether nematic fluctuation can induce superconductivity. Here, the authors study single crystals of FeSe1−xTex showing enhanced superconductivity upon suppression of nematicity. [ABSTRACT FROM AUTHOR]

The emission of muonium (⁠|$\mu^+e^-$|⁠) atoms into vacuum from silica aerogel with laser ablation on its surface was studied with various ablation structures at room temperature using the subsurface muon beams at TRIUMF and Japan Proton Accelerator Research Complex (J-PARC). Laser ablation was applied to produce holes or grooves with typical dimensions of a few hundred |$\mu$| m to a few mm, except for some extreme conditions. The measured emission rate tends to be higher for larger fractions of ablation opening and for shallower depths. More than a few ablation structures reach the emission rates similar to the highest achieved in past measurements. The emission rate is found to be stable at least for a couple of days. Measurements of spin precession amplitudes for the produced muonium atoms and remaining muons in a magnetic field determine a muonium formation fraction of |$(65.5 \pm 1.8)$| %. The precession of the polarized muonium atoms is also observed clearly in vacuum. A projection of the emission rates measured at TRIUMF to the corresponding rates at J-PARC is demonstrated taking the different beam condition into account reasonably. [ABSTRACT FROM AUTHOR]

The search for thermoelectric materials for power generation and for solid-state cooling has led to increased interest of layered cobalt-containing oxides because of their thermal stability at high temperature and their desirable thermoelectric properties. This paper examines the effect of substitution of Co in the layered pervoskite Ba2Ho(Cu3-xCox)O6+y (x=0.3, 0.4, 0.5, 0.6, and 1.0). Structural analysis using the neutron Rietveld refinement technique reveals that when x≤0.4, Co substitutes mainly for Cu in the “chain sites” of the Ba2Ho(Cu3-xCox)O6+y structure. As x>0.4, Co also enters in the Cu-O “plane sites” as well. The thermoelectric properties of polycrystalline Ba2Ho(Cu3-xCox)O6+y samples were studied in the temperature range of 10–390 K. In general, as the cobalt content x increases, the resistivity and Seebeck coefficient of these samples increase while the thermal conductivity decreases. Among the five Ba2Ho(Cu3-xCox)O6+y compositions, the x=0.4 member gives the highest figure of merit ZT of ≈0.02 at approximately 270 K. [ABSTRACT FROM AUTHOR]

This paper reports the texture analysis as well as the identification of two crystalline phases between a thin film of monoclinic Ca3Co4O9 and a cubic (100) Si substrate, using a diffractometer equipped with a two-dimensional area detector. No reflections other than 00ℓ were observed in the symmetric configuration using an x-ray powder diffraction scan (Bragg-Brentano geometry). Pole figures collected for six reflections using asymmetric configurations did not show ab-plane epitaxial relationships between the film and the substrate. These results establish the Ca3Co4O9 fiber texture of the film with the (001) pole parallel to the surface normal. Single-crystal-like second phases, CaCoSi2O6 and CoO, presumably the interface reaction products of Ca3Co4O9 with the substrate Si, were identified. The near four-fold symmetry and the similar intensity displayed by the 220 reflection from the CaCoSi2O6 structure indicated an epitaxial relation between CaCoSi2O6 and Si, with four symmetry-induced variants being generated with approximately equal volume fractions. [ABSTRACT FROM AUTHOR]

The effect of substitution of Co in the layered pervoskite [Ba.sub.2]Ho([Cu.sub.3-x][Co.sub.x])[O.sub.6+y] is examined. The studies have shown that as the cobalt content x has increased the resistivity and Seebeck coefficient of these samples have increased while the thermal conductivity has decreased.

The texture analysis as well as the identification of two crystalline phases between a thin film of monoclinic [Ca.sub.3][Co.sub.4][O.sub.9] and a cubic (100) Si substrate is presented.

In this article, a new type of comparison theorem for some second-order nonlinear parabolic systems with nonlinear boundary conditions is given, which can cover classical linear boundary conditions, such as the homogeneous Dirichlet or Neumann boundary condition. The advantage of our comparison theorem over the classical ones lies in the fact that it enables us to compare two solutions satisfying different types of boundary conditions. As an application of our comparison theorem, we can give some new results on the existence of blow-up solutions of some parabolic equations and systems with nonlinear boundary conditions.