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1.
《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2021,38(6):1681-1702
We prove the existence of a -normalized solitary wave solution for the Maxwell-Dirac equations in (3+1)-Minkowski space. In addition, for the Coulomb-Dirac model, describing fermions with attractive Coulomb interactions in the mean-field limit, we prove the existence of the (positive) energy minimizer. 相似文献
2.
《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2021,38(5):1337-1371
In this paper we consider minimizers of the functional where is a bounded open set and where are the first k eigenvalues on Ω of an operator in divergence form with Dirichlet boundary condition and with Hölder continuous coefficients. We prove that the optimal sets have finite perimeter and that their free boundary is composed of a regular part, which is locally the graph of a -regular function, and a singular part, which is empty if , discrete if and of Hausdorff dimension at most if , for some . 相似文献
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J. Conrad J. Cohen-Tanugi L. E. Strigari 《Journal of Experimental and Theoretical Physics》2015,121(6):1104-1135
The launch of the gamma-ray telescope Fermi Large Area Telescope (Fermi-LAT) started a pivotal period in indirect detection of dark matter. By outperforming expectations, for the first time a robust and stringent test of the paradigm of weakly interacting massive particles (WIMPs) is within reach. In this paper, we discuss astrophysical targets for WIMP detection and the challenges they present, review the analysis tools which have been employed to tackle these challenges, and summarize the status of constraints on and the claimed detections in the WIMP parameter space. Methods and results will be discussed in comparison to Imaging Air Cherenkov Telescopes. We also provide an outlook on short term and longer term developments. 相似文献
5.
Dr. Radu Custelcean Neil J. Williams Charles A. Seipp 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(36):10671-10675
An effective approach to sulfate separation from aqueous solutions is based on the crystallization of extended [SO4(H2O)52−]n sulfate–water clusters with a bis(guanidinium) ligand. The ligand was generated in situ by hydrazone condensation in water, thereby bypassing the need for elaborate syntheses, tedious purifications, and organic solvents. Crystallization of sulfate–water clusters represents an alternative approach to the now established sulfate separation strategies that involve encapsulation of the “naked” anion. 相似文献
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Hemant Kumar Nashine Ravi P. Agarwal Zoran Kadelburg 《Journal of Fixed Point Theory and Applications》2017,19(4):2309-2325
Kikkawa and Suzuki (Nonlinear Anal 69:2942–2949, 2008) and Kikkawa and Suzuki (Fixed Point Theory Appl, 2008, Art. ID 649749) proved some fixed point results that are generalizations of Kannan’s, Nadler’s and Suzuki’s fixed point theorems. Here, we present fixed point results of this kind for multivalued mappings in the setting of \(\mathcal {H}^+\)-metric spaces. The theorems provided allow upgrading of some known results which is shown by examples. Moreover, we give a homotopy result as an application of our main theorem. 相似文献
9.
Eliezer Ortiz Madeline M. Evarts Zachary H. Strong Jonathan Z. Shezaf Prof. Michael J. Krische 《Angewandte Chemie (International ed. in English)》2023,62(23):e202303345
The first metal-catalyzed oxidative alkynylations of primary alcohols or aldehydes to form α,β-acetylenic ketones (ynones) are described. Deuterium labelling studies corroborate a novel reaction mechanism in which alkyne hydroruthenation forms a transient vinylruthenium complex that deprotonates the terminal alkyne to form the active alkynylruthenium nucleophile. 相似文献
10.
The fracture process of reinforced composite materials is examined. In the outer region of the crack tip anisotropic continuum mechanics is employed, while for the crack tip region a heterogeneous micromechanical model is proposed. A solution is obtained using combined boundary layer — non-linear finite elements. 相似文献