Results 61 to 70 of about 242,274 (310)

Least Squares Problems with Absolute Quadratic Constraints

Journal of Applied Mathematics, 2012
This paper analyzes linear least squares problems with absolute quadratic constraints. We develop a generalized theory following Bookstein's conic-fitting and Fitzgibbon's direct ellipse-specific fitting.
R. Schöne, T. Hanning
doaj   +1 more source

Tailoring the Microstructure of B‐Cation Octahedra in Halide Double Perovskites for Efficient Selective CO2‐to‐CO Photoreduction

Advanced Functional Materials, EarlyView.
The thermodynamic obstacle of CO2‐to‐CO conversion over metal halide perovskite photocatalysts is addressed by modulating the local electronic structure. A 13‐fold improvement in selective CO2 photoreduction to CO is achieved, with ≈100% selectivity.
Chunhua Wang, Wenjing Shen, Zhirun Xie, Yannan Wang, Yang Ding, Ning Han, Michael K.H. Leung, Biao Liu, Zhi Zhu, Yun Hau Ng   +9 more
wiley   +1 more source

Pentagonal 2D Altermagnets: Material Screening and Altermagnetic Tunneling Junction Device Application

Advanced Functional Materials, EarlyView.
From a database of 170 pentagonal 2D materials, 4 candidates exhibiting altermagnetic ordering are screened. Furthermore, the spin‐splitting and unconventional boundary states in the pentagonal 2D altermagnetic monolayer MnS2 are investigated. A MnS2‐based altermagnetic tunneling junction is designed and, through ab initio quantum transport simulations,
Jianhua Wang, Xingyue Yang, Zongmeng Yang, Jing Lu, Pin Ho, Wenhong Wang, Yee Sin Ang, Zhenxiang Cheng, Shibo Fang   +8 more
wiley   +1 more source

Solution of the discrete Wheeler-DeWitt equation in the vicinity of small scale factors and quantum mechanics in the space of negative constant curvature [PDF]

, 2014
The asymptotic of the solution of the discrete Wheeler-DeWitt equation is found in the vicinity of small scale factors. It is shown that this problem is equivalent to the solution of the stationary Schr\"{o}dinger equation in the (super) space of ...
Cherkas, S. L., Kalashnikov, V. L.
core   +2 more sources

Ordering non-bipartite unicyclic graphs with pendant vertices by the least Q-eigenvalue

Journal of Inequalities and Applications, 2016
A unicyclic graph is a connected graph whose number of edges is equal to the number of vertices. Fan et al. (Discrete Math. 313:903-909, 2013) and Liu et al. (Electron. J.
Shu-Guang Guo, Xiaorong Liu, Rong Zhang, Guanglong Yu   +3 more
doaj   +1 more source

Lower bounds of the minimum eigenvalue for $M$-matrices

, 2017
Some monotone increasing sequences of the lower bounds for the minimum eigenvalue of $M$-matrices are given. It is proved that these sequences are convergent and improve some existing results. Numerical examples show that these sequences are more accurate than some existing results and could reach the true value of the minimum eigenvalue in some cases.
Zhao, Jianxing, Sang, Caili
openaire   +2 more sources

Enhancing the Photocatalytic Performance of Carbon Nitrides Through Controlled Local Structure Modification

Advanced Functional Materials, EarlyView.
This work utilizes poly(heptazine imides) as a model system to demonstrate how fine‐tuning the crystal structure influences the photocatalytic properties of layered carbon nitrides in the hydrogen evolution reaction. In particular, the nature of rotational defects and the hydration shell of cations are key contributors to enhanced hydrogen evolution ...
Diana V. Piankova, Hannes Zschiesche, Alexander P. Tyutyunnik, Erik Svensson Grape, Caio Vinícius C. R. da Silva, Walber G. Guimarães Junior, Andre. F. de Moura, Izadora F. Reis, Gabriel Ali A. Diab, José Balena G. Filho, Ivo F. Teixeira, Nadezda V. Tarakina   +11 more
wiley   +1 more source

A note on lower bounds for the first eigenvalue of the Witten-Laplacian [PDF]

, 2014
In this note, by extending the arguments of Ling (Illinois J. Math. 51, 853-860, 2007) to Bakry-Emery geometry, we shall give lower bounds for the first nonzero eigenvalue of the Witten-Laplacian on compact Bakry-Emery manifolds in the case that the ...
Tadano, Homare
core  

Existence of a principal eigenvalue for the Tricomi problem

Electronic Journal of Differential Equations, 2000
The existence of a principal eigenvalue is established for the Tricomi problem in normal domains; that is, the existence of a positive eigenvalue of minimum modulus with an associated positive eigenfunction.
Daniela Lupo, Kevin R. Payne
doaj  

Computational Modeling of Reticular Materials: The Past, the Present, and the Future

Advanced Materials, EarlyView.
Reticular materials are advanced materials with applications in emerging technologies. A thorough understanding of material properties at operating conditions is critical to accelerate the deployment at an industrial scale. Herein, the status of computational modeling of reticular materials is reviewed, supplemented with topical examples highlighting ...
Wim Temmerman, Ruben Goeminne, Kuber Singh Rawat, Veronique Van Speybroeck   +3 more
wiley   +1 more source