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Products of positive definite matrices. II [PDF]
Pacific Journal of Mathematics, 1967 I. The author gives, for every positive integer \(j\), necessary and sufficient conditions for a \(2\times 2\) real matrix (with positive determinant) to be a product of \(j\) positive definite real symmetric matrices (if \(j\ge 5\), every real matrix with positive determinant can be written as such a product).
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Modified MXene Aerogel With Broadband Microwave Absorption Inspired by Melanophila Acuminata Beetle
Advanced Science, EarlyView.This work introduces a novel biomimetic strategy inspired by the infrared‐sensing sensilla of the Melanophila acuminata beetle. We have designed a multi‐level aerogel, featuring a three‐dimensional carbon framework decorated with synergistic CeO2 nanoparticles and Ti3C2Tx MXene nanosheets.
Zhiwei Liu +6 more
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Data‐Driven Discovery of Unconventional Antiferromagnets
Advanced Science, EarlyView.A high‐throughput workflow that combines the physics‐informed pre‐screening, high‐throughput exchange calculations, Luttinger‐Tisza analysis and symmetry classification is established for accurate identification of unconventional antiferromagnets from the broad structural database.
Qirui Cui +3 more
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Distributional boundary values of analytic functions and positive definite distributions
Nonlinear Analysis, 2015 We propose necessary and sufficient conditions for a distribution (generalized function) fof several variables to be positive definite. For this purpose, certain analytic extensions of f to tubular domains in complex space Cn are studied. The main result
Saulius Norvidas
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The positive definite completion problem revisited [PDF]
, 2008 In [R. Grone, C.R. Johnson, E. Sa, H. Wolkowicz, Positive definite completions of partial Hermitian matrices, Linear Algebra Appl. 58 (1984) 109–124] the positive definite (semi-) completion problem in which the underlying graph is chordal was solved ...
Smith, Ronald L.
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Advanced Science, EarlyView.Combining recently established two ground‐breaking concepts, the adoption of WCAs and the use of alkoxyalkylamine‐based solvents in electrolyte formulations for rechargeable magnesium metal batteries, has led to unexpectedly unsuccessful electrochemical Mg plating/stripping performance. Comprehensive experimental and computational analyses revealed the
Toshihiko Mandai +4 more
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On the Positive Definite Solutions of a Nonlinear Matrix Equation
Journal of Applied Mathematics, 2013 The positive definite solutions of the nonlinear matrix equation are discussed. A necessary and sufficient condition for the existence of positive definite solutions for this equation is derived.
Panpan Liu, Shugong Zhang, Qingchun Li
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Some trace inequalities for matrix means
Journal of Inequalities and Applications, 2016 In this short note, we present some trace inequalities for matrix means. Our results are generalizations of the ones shown by Bhatia, Lim, and Yamazaki.
Limin Zou, Yang Peng
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Positive Definiteness of Forms: Numerical Identification
SIAM Journal on Control and Optimization, 2002 The paper deals with the question about positive definiteness or semidefiniteness of abstract quadratic forms on a Hilbert space (or, more generally, polynomial homogeneous forms of an even degree) arises in numerous fields of mathematics and its applications.
Aram V. Arutyunov, Alexey F. Izmailov
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ZrCo3B2 and HfCo3B2 Electrodes Go on Stage for Oxygen Evolution Reaction
Advanced Science, EarlyView.The intermetallic compounds ZrCo3B2 and HfCo3B2 with distinctive chemical bonding features are excellent OER precursors, restructuring into OER‐active electrocatalysts delivering significantly high OER activities compared to the elemental Co, which is obvious from their lower onset potentials and increased obtained current densities.
Fatma Aras +4 more
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