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51.
52.
Energy gaps in a spacetime crystal 总被引:1,自引:0,他引:1
This Letter presents an analysis of the band structure of a spacetime potential lattice created by a standing electromagnetic wave. We show that there are energy band gaps. We estimate the effect, and propose a measurement that could confirm the existence of such phenomena. 相似文献
53.
Michael Grouchko Alexander Kamyshny Keren Ben-Ami Shlomo Magdassi 《Journal of nanoparticle research》2009,11(3):713-716
Synthesis of well dispersed copper nanoparticles was achieved by reduction of copper nitrate in aqueous solution using hydrazine
monohydrate as a reducer in the presence of preformed silver nanoparticles as catalysts. It has been demonstrated that addition
of silver nanoparticles to the reaction mixture leads to formation of aqueous dispersion of copper nanoparticles and also
results in a drastic reduction in reaction time compared to procedures reported in the literature. The absorption spectrum
of the dispersions, HR-TEM and STEM images and XRD pattern indicate the formation of copper nanoparticles with particle size
in the range of 5–50 nm. 相似文献
54.
We prove that the quantum double of the quasi-Hopf algebra of dimension attached in [P. Etingof, S. Gelaki, On radically graded finite-dimensional quasi-Hopf algebras, Mosc. Math. J. 5 (2) (2005) 371–378] to a simple complex Lie algebra and a primitive root of unity q of order n2 is equivalent to Lusztig's small quantum group (under some conditions on n). We also give a conceptual construction of using the notion of de-equivariantization of tensor categories. 相似文献
55.
Gal Ehrlich Moshe Zohar Mark Auslender Roy Avrahamy Shlomo Hava 《Optical and Quantum Electronics》2018,50(1):48
We study a triangular arrangement of two flat mirrors and a grating mirror for coupling a \(-1{\mathrm{st}}\) diffracted order light beam into a traveling-wave intra-cavity light recirculation and out-of-cavity output, combining the \(0\,{\mathrm{th}}\) and the repeatedly diffracted secondary \(+1{\mathrm{st}}\) order beams. The thus designed and then optimized grating Fabry-Perot ring cavity demonstrates high output contrast and detection resolution for wavelength, cavity length and incidence angle. 相似文献
56.
Shlomo S. Razamat 《Letters in Mathematical Physics》2014,104(6):673-690
We define an infinite sequence of superconformal indices, ${{\mathcal{I}}_n}$ , generalizing the Schur index for ${{\mathcal{N}}=2}$ theories. For theories of class ${{\mathcal{S}}}$ we then suggest a recursive technique to completely determine ${{\mathcal{I}}_n}$ . The information encoded in the sequence of indices is equivalent to the ${{\mathcal{N}}=2}$ superconformal index depending on a maximal set of fugacities. Mathematically, the procedure suggested in this note provides a perturbative algorithm for computing a set of eigenfunctions of the elliptic Ruijsenaars–Schneider model. 相似文献
57.
This work demonstrates the unique features of the never used before Py?BrF(3) complex in the field of aromatic organic fluorinations. The main disadvantage of the noncomplexed BrF(3) is the fact that usually, in addition to the desired fluorination, a parallel electrophilic aromatic bromination takes place as well. Use of the Py?BrF(3) complex reduces this electrophilic bromination, which is observed with most reagents based on fluorine and bromine [BrF]. 相似文献
58.
59.
Doping silver nanoparticles in AOT lyotropic lamellar phases 总被引:1,自引:0,他引:1
The organic lyotropic liquid crystal with long-range structural order is used as template to assemble inorganic/organic hybrid by doping pre-fabricated Ag nanoparticles. The lamellar hybrid with both hydrophilic and hydrophobic particles doped simultaneously is realized for the first time. The change of template structure after doping and the stability origin of dual-doped system are characterized by small angle X-ray scattering and polarized optical microscopy. Results show that the interaction and space matching between surfactant bilayers and doped particles are key factors to obtain stable hybrid. 相似文献
60.
Summary. In this paper we again consider the rate of convergence of the conjugate gradient method. We start with a general analysis
of the conjugate gradient method for uniformly bounded solutions vectors and matrices whose eigenvalues are uniformly bounded
and positive. We show that in such cases a fixed finite number of iterations of the method gives some fixed amount of improvement
as the the size of the matrix tends to infinity. Then we specialize to the finite element (or finite difference) scheme for
the problem . We show that for some classes of function we see this same effect. For other functions we show that the gain made by performing a fixed number of iterations of the
method tends to zero as the size of the matrix tends to infinity.
Received July 9, 1998 / Published online March 16, 2000 相似文献