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1. Superprotonic conductivity in RbH2−3y(PO4)1−y: a phosphate deficient analog to cubic CsH2PO4 in the (1−x)RbH2PO4 – xRb2HPO4 system

   https://doi.org/10.1039/D3MH00852E  

   Xiong, Grace; Wang, Louis S.; Haile, Sossina M. (November 2023, Materials Horizons)

   The compounds RbH2PO4 and Rb5H7(PO4)4 display eutectoid behavior, with superprotonic α-RbH2−3y(PO4)1−y forming at a eutectoid temperature of 244 °C in a cubic, CsCl-type structure with a high concentration of phosphate vacancies. 

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2. Drawing Planar Graphs and 1-Planar Graphs Using Cubic Bézier Curves with Bounded Curvature

   https://doi.org/10.4230/LIPIcs.GD.2024.39  

   Eppstein, David; Goodrich, Michael T; Illickan, Abraham M (October 2024, Schloss Dagstuhl – Leibniz-Zentrum für Informatik)

   Felsner, Stefan; Klein, Karsten (Ed.)

   We study algorithms for drawing planar graphs and 1-planar graphs using cubic Bézier curves with bounded curvature. We show that any n-vertex 1-planar graph has a 1-planar RAC drawing using a single cubic Bézier curve per edge, and this drawing can be computed in O(n) time given a combinatorial 1-planar drawing. We also show that any n-vertex planar graph G can be drawn in O(n) time with a single cubic Bézier curve per edge, in an O(n)× O(n) bounding box, such that the edges have Θ(1/degree(v)) angular resolution, for each v ∈ G, and O(√n) curvature. 

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3. Observations of phase changes in monoolein during high viscous injection

   https://doi.org/10.1107/S1600577522001862  

   Wells, Daniel J.; Berntsen, Peter; Balaur, Eugeniu; Kewish, Cameron M.; Adams, Patrick; Aquila, Andrew; Binns, Jack; Boutet, Sébastien; Broomhall, Hayden; Caleman, Carl; et al (May 2022, Journal of Synchrotron Radiation)

   Serial crystallography of membrane proteins often employs high-viscosity injectors (HVIs) to deliver micrometre-sized crystals to the X-ray beam. Typically, the carrier medium is a lipidic cubic phase (LCP) media, which can also be used to nucleate and grow the crystals. However, despite the fact that the LCP is widely used with HVIs, the potential impact of the injection process on the LCP structure has not been reported and hence is not yet well understood. The self-assembled structure of the LCP can be affected by pressure, dehydration and temperature changes, all of which occur during continuous flow injection. These changes to the LCP structure may in turn impact the results of X-ray diffraction measurements from membrane protein crystals. To investigate the influence of HVIs on the structure of the LCP we conducted a study of the phase changes in monoolein/water and monoolein/buffer mixtures during continuous flow injection, at both atmospheric pressure and under vacuum. The reservoir pressure in the HVI was tracked to determine if there is any correlation with the phase behaviour of the LCP. The results indicated that, even though the reservoir pressure underwent (at times) significant variation, this did not appear to correlate with observed phase changes in the sample stream or correspond to shifts in the LCP lattice parameter. During vacuum injection, there was a three-way coexistence of the gyroid cubic phase, diamond cubic phase and lamellar phase. During injection at atmospheric pressure, the coexistence of a cubic phase and lamellar phase in the monoolein/water mixtures was also observed. The degree to which the lamellar phase is formed was found to be strongly dependent on the co-flowing gas conditions used to stabilize the LCP stream. A combination of laboratory-based optical polarization microscopy and simulation studies was used to investigate these observations. 

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4. Global Well-Posedness for the Defocusing, Cubic, Nonlinear Wave Equation in Three Dimensions for Radial Initial Data in $$\dot{H}^{s} \times \dot{H}^{s - 1}$$, $$s> \frac{1}{2}$$

   https://doi.org/10.1093/imrn/rnx323  

   Dodson, Benjamin (February 2018, International Mathematics Research Notices)

   Abstract In this paper we study the defocusing, cubic nonlinear wave equation in three dimensions with radial initial data. The critical space is $$\dot{H}^{1/2} \times \dot{H}^{-1/2}$$. We show that if the initial data is radial and lies in $$\left (\dot{H}^{s} \times \dot{H}^{s - 1}\right ) \cap \left (\dot{H}^{1/2} \times \dot{H}^{-1/2}\right )$$ for some $$s> \frac{1}{2}$$, then the cubic initial value problem is globally well-posed. The proof utilizes the I-method, long time Strichartz estimates, and local energy decay. This method is quite similar to the method used in [11]. 

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5. Environmentally friendly thermoelectric sulphide Cu ₂ ZnSnS ₄ single crystals achieving a 1.6 dimensionless figure of merit ZT

   https://doi.org/10.1039/D1TA02978A  

   Nagaoka, Akira; Yoshino, Kenji; Masuda, Taizo; Sparks, Taylor D.; Scarpulla, Michael A.; Nishioka, Kensuke (July 2021, Journal of Materials Chemistry A)

   Thermoelectrics (TEs) are an important class of technology that harvest electric power directly from heat sources. When designing both high performance and environmentally friendly TE materials, the pseudo-cubic structure has great theoretical potential to maximize the dimensionless figure of merit ZT . The TE multinary single crystal with a pseudo-cubic structure paves a new path toward manipulating valley degeneracy and anisotropy with low thermal conductivity caused by short-range lattice distortion. Here, we report a record high ZT = 1.6 around 800 K realized in a totally environmentally benign p-type Na-doped Cu 2 ZnSnS 4 (CZTS) single crystal. The exceptional performance comes from a high power factor while maintaining intrinsically low thermal conductivity. The combination of the pseudo-cubic structure and intrinsic properties of the CZTS single crystal takes advantage of simple material tuning without complex techniques. 

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