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1. A z = 0 Multiwavelength Galaxy Synthesis. I. A WISE and GALEX Atlas of Local Galaxies

   https://doi.org/10.3847/1538-4365/ab3925  

   Leroy, Adam K.; Sandstrom, Karin M.; Lang, Dustin; Lewis, Alexia; Salim, Samir; Behrens, Erica A.; Chastenet, Jérémy; Chiang, I-Da; Gallagher, Molly J.; Kessler, Sarah; et al (October 2019, The Astrophysical Journal Supplement Series)
2. Temperature-dependent dielectric behavior of A 6 B 2O17 ( A  = Zr, Hf; B  = Nb, Ta) phases

   https://doi.org/10.1063/5.0219964  

   Spurling, R Jackson; Marakovits, Michael T; Hossain, Arafat; Almishal, Saeed_S I; Perini, Steven E; Lanagan, Michael T; Maria, Jon-Paul (August 2024, Applied Physics Letters)

   We report on temperature-dependent dielectric behavior of disordered ternary A6B2O17 (A = Zr, Hf; B = Nb, Ta)-form oxides in the GHz frequency range. The microwave dielectric properties including relative permittivity, dielectric loss, and temperature-dependent relative permittivity were characterized using cylindrical dielectric resonators using a resonant post measurement technique. Dielectric measurements through the resonant post method approach generally agree with dielectric measurements of A6B2O17 bulk ceramics measured through standard resonant post techniques. Coefficients describing the temperature-dependent relative permittivity for ternary A6B2O17 phases are strongly positive, suggesting contributions to polarizability arising from long-range mechanisms potentially associated with structural disorder. These observations support the working hypothesis that material functionality can be engineered by the chemical diversity and structural disorder possible in high configurational entropy A6B2O17 phases. 

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3. Extended Cation Solubility in the A 6 B 2O17 ( A = Zr, Hf; B = Nb, Ta) Family of Phases

   https://doi.org/10.1093/mam/ozae044.661  

   Jackson_Spurling, R; Maria, Jon-Paul (July 2024, Microscopy and Microanalysis)
4. Synthesis of metastable Ruddlesden–Popper titanates, ( A TiO3) n A O, with n ≥ 20 by molecular-beam epitaxy

   https://doi.org/10.1063/5.0101202  

   Barone, Matthew_R; Jeong, Myoungho; Parker, Nicholas; Sun, Jiaxin; Tenne, Dmitri_A; Lee, Kiyoung; Schlom, Darrell_G (September 2022, APL Materials)

   We outline a method to synthesize (ATiO3)nAO Ruddlesden–Popper phases with high-n, where the A-site is a mixture of barium and strontium, by molecular-beam epitaxy. The precision and consistency of the method described is demonstrated by the growth of an unprecedented (SrTiO3)50SrO epitaxial film. We proceed to investigate barium incorporation into the Ruddlesden–Popper structure, which is limited to a few percent in bulk, and we find that the amount of barium that can be incorporated depends on both the substrate temperature and the strain state of the film. At the optimal growth temperature, we demonstrate that as much as 33% barium can homogeneously populate the A-site when films are grown on SrTiO3 (001) substrates, whereas up to 60% barium can be accommodated in films grown on TbScO3 (110) substrates, which we attribute to the difference in strain. This detailed synthetic study of high n, metastable Ruddlesden–Popper phases is pertinent to a variety of fields from quantum materials to tunable dielectrics. 

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5. A Chandra survey of z ≥ 4.5 quasars

   https://doi.org/10.1093/mnras/stab1042  

   Li, Jiang-Tao; Wang, Feige; Yang, Jinyi; Bregman, Joel N; Fan, Xiaohui; Zhang, Yuchen (May 2021, Monthly Notices of the Royal Astronomical Society)

   null (Ed.)

   ABSTRACT X-ray observations provide a unique probe of the accretion disc corona of supermassive black holes (SMBHs). In this paper, we present a uniform Chandra X-ray data analysis of a sample of 152 z ≥ 4.5 quasars. We firmly detect 46 quasars of this sample in 0.5–2 keV above 3σ and calculate the upper limits of the X-ray flux of the remaining. We also estimate the power-law photon index of the X-ray spectrum of 31 quasars. 24 of our sample quasars are detected in the FIRST or NVSS radio surveys; all of them are radio-loud. We statistically compare the X-ray properties of our z ≥ 4.5 quasars to other X-ray samples of active galactic nuclei (AGNs) at different redshifts. The relation between the rest-frame X-ray luminosity and other quasar parameters, such as the bolometric luminosity, UV luminosity, or SMBH mass, shows large scatters. These large scatters can be attributed to the narrow luminosity range at the highest redshift, the large measurement error based on relatively poor X-ray data, and the inclusion of radio-loud quasars in the sample. The LX–LUV relationship is significantly sublinear. We do not find a significant redshift evolution of the LX–LUV relation, expressed either in the slope of this relation, or the departure of individual AGNs from the best-fitting αOX–LUV relation (ΔαOX). The median value of the X-ray photon index is Γ ≈ 1.79, which does not show redshift evolution from z = 0 to z ∼ 7. The X-ray and UV properties of the most distant quasars could potentially be used as a standard candle to constrain cosmological models. The large scatter of our sample on the Hubble diagram highlights the importance of future large unbiased deep X-ray and radio surveys in using quasars in cosmological studies. 

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