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81.
We postulate the energy-momentum functionE for the ECSK theory of gravity and formulate the functional Hamiltonian equation in terms of the energy-momentum functionE and the symplectic 2-form . The system of partial differential equations which follows from the functional Hamilton equation is equivalent to the system of variational equations of the ECSK theory. The Hamiltonian method gives rise to a natural division of these equations into 10 constraint equations and the set of dynamical equations. We discuss the geometric sense of the constraint equations and their relations to the initial value problem. 相似文献
82.
Kazimierz Frąckiewicz 《General Relativity and Gravitation》1985,17(10):939-952
This paper is the first of a two-article series in which the connections between the gauge group, degeneration, and degrees of freedom in the ECSK theory coupled to an arbitrary tensor field are discussed. In this paper a multisymplectic formulation of the ECSK theory is presented and the symplectic 2-form, which plays a leading role in our considerations, is found. 相似文献
83.
Kazimierz Szymiczek 《代数通讯》2013,41(4):1125-1149
A Simplicial derivation procedure for crossed module valued functors is established. As a consequence, a theory of higher Baer invariants and relative homology is settle on crossed modules. Then we illustrative how this method is efficient, as it extends classical formulations and results, like various known five term sequences on crossed modules by Conduché and Ellis (1989), the author (1993) and Ladra and R-Grandjeán (1994). 相似文献
84.
Abstract Per(6-deoxy-6-halo) cyclodextrins (bromo, chloro or iodo) have been prepared in excellent yield and high selectivity by treatment of the native cyclodextrins with the corresponding N-halosuccinimide and triphenylphosphine in N,N-dimethylformamide. 相似文献
85.
Jia-Yin Wang Yao Tang Guan-Zhao Wu Sai Zhang Hossein Rouh Shengzhou Jin Ting Xu Yu Wang Daniel Unruh Kazimierz Surowiec Prof. Dr. Yanzhang Ma Yunze Li Courtney Katz Prof. Dr. Hongjun Liang Prof. Dr. Weilong Cong Prof. Dr. Guigen Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(7):e202104102
Unprecedented chiral multilayer folding 3D polymers have been assembled and regulated by uniform and differentiated aromatic chromophore units between naphthyl piers. Screening catalysts, catalytic systems and monomers were proven to be crucial for asymmetric catalytic Suzuki–Miyaura polycouplings for this assembly. X-ray crystallography of the corresponding dimers and trimers revealed the absolute configuration and the intermolecular packing pattern. Up to 61 960 Mw/41 900 Mn and m/z 4317 for polymers and oligomers, as confirmed by gel permeation chromatography (GPC) and MALDI-TOF MS, indicated that these frameworks were composed of multiple stacked layers. The resulting multiple π-assemblies exhibited remarkable optical properties in aggregated states (photoluminescence in solids and aggregation-induced emission in solutions), as well as reversible redox properties in electrochemical performance. 相似文献
86.
Aequationes mathematicae - The notion of $$(m,M,\Psi )$$ -Schur-convexity is introduced and functions generating $$(m,M,\Psi )$$ -Schur-convex sums are investigated. An extension of the... 相似文献
87.
In many cases known methods of detecting oscillations of arithmetic error terms involve certain smoothing pro‐cedures. Usually an application of the smoothing operator does not change significantly the order of magnitude of the error under consideration. This is so for instance in the case of the classical error terms known in the prime number theory. The main purpose of this paper is to show that the situation for primes is not general. Considering the error term in the asymptotic formula for the Euler totient function we show that just one application of an integral smoothing operator changes situation dramatically: the order of magnitude of drops from x to √x (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
88.
Hamid Reza Moradi Mohsen Erfanian Omidvar Muhammad Adil Khan Kazimierz Nikodem 《Aequationes Mathematicae》2018,92(1):25-37
In this paper we use basic properties of strongly convex functions to obtain new inequalities including Jensen type and Jensen–Mercer type inequalities. Applications for special means are pointed out as well. We also give a Jensen’s operator inequality for strongly convex functions. As a corollary, we improve the Hölder-McCarthy inequality under suitable conditions. More precisely we show that if \(Sp\left( A \right) \subset \left( 1,\infty \right) \), then and if \(Sp\left( A \right) \subset \left( 0,1 \right) \), then for each positive operator A and \(x\in \mathcal {H}\) with \(\left\| x \right\| =1\).
相似文献
$$\begin{aligned} {{\left\langle Ax,x \right\rangle }^{r}}\le \left\langle {{A}^{r}}x,x \right\rangle -\frac{{{r}^{2}}-r}{2}\left( \left\langle {{A}^{2}}x,x \right\rangle -{{\left\langle Ax,x \right\rangle }^{2}} \right) ,\quad r\ge 2 \end{aligned}$$
$$\begin{aligned} \left\langle {{A}^{r}}x,x \right\rangle \le {{\left\langle Ax,x \right\rangle }^{r}}+\frac{r-{{r}^{2}}}{2}\left( {{\left\langle Ax,x \right\rangle }^{2}}-\left\langle {{A}^{2}}x,x \right\rangle \right) ,\quad 0<r<1 \end{aligned}$$
89.
The celebrated Brouwer’s Fixed Point Theorem is dated in 1912. Its extension to compact set setting in Banach spaces due to
Schauder appeared in 1930. Immediately it raised the question whether the Theorem can be extended to noncompact setting. The
works of Kakutani, Klee, Benyamini and Sterfeld, Sternfeld and Lim solved the qualitative part of the problem. Lack of compactness
makes the statement of the theorem false. However, there are some quantitative aspects of the question. The two basic are
called minimal displacement problem, and optimal retraction problem. The aim of this article is to present the historical back ground and possibly, up to date state of investigations in this
field. A list of open problems with comments will be discussed. 相似文献
90.
Yanfei Yang Xiaodan Cao Kazimierz Surowiec Richard A. Bartsch 《Journal of inclusion phenomena and macrocyclic chemistry》2010,66(1-2):163-169
A regioisomer of a previously reported p-tert-butylcalix[4]arene-1,3-thiacrown-5 di(carboxylic acid) is prepared in which the thiacrown ring attachment sites are moved from distal phenolic oxygens of a cone p-tert-butylcalix[4]arene scaffold to proximal phenolic oxygens. The influence of this structural variation in the di-ionizable calixcrown ligand on competitive solvent extractions of alkali metal cations and of alkaline earth metal cations and single species solvent extractions of Hg2+ and Pb2+ from aqueous solutions into chloroform is evaluated. 相似文献