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31.
We discuss the realization of the quantum-critical non-Fermi-liquid state, originally discovered within the two-impurity Kondo model, in double-quantum-dot systems. Contrary to common belief, the corresponding fixed point is robust against particle-hole and various other asymmetries and is unstable only to charge transfer between the two dots. We propose an experimental setup where such charge transfer processes are suppressed, allowing a controlled approach to the quantum-critical state. We also discuss transport and scaling properties in the vicinity of the critical point. 相似文献
32.
Károly Böröczky Károly Böröczky Jr. Gergely Wintsche 《Periodica Mathematica Hungarica》2006,53(1-2):83-102
Summary Given <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"3"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"4"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"5"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"6"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>r>1$,
we search for the convex body of minimal volume in
$\mathbb{E}^3$ that contains a unit ball, and whose extreme points are of
distance at least $r$ from the centre of the unit ball. It is known that the
extremal body is the regular octahedron and icosahedron for suitable values of
$r$. In this paper we prove that if $r$ is close to one then the typical faces
of the extremal body are asymptotically regular triangles. In addition we prove
the analogous statement for the extremal bodies with respect to the surface
area and the mean width. 相似文献
33.
Károly Böröczky Jr. Ildikó Fábián Gergely Wintsche 《Periodica Mathematica Hungarica》2006,53(1-2):103-113
Summary We determine the minimal radius of <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource
Format="TEX"><![CDATA[<InlineEquation ID=IE"3"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"4"><EquationSource
Format="TEX"><![CDATA[<InlineEquation ID=IE"5"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>n=2$,
$d$ or $2d$ congruent balls,
which cover the $d$-dimensional crosspolytope. 相似文献
34.
Simone Mastrogiovanni Christos Karathanasis Jonathan Gair Gregory Ashton Stefano Rinaldi Hsiang-Yu Huang Gergely Dálya 《Annalen der Physik》2024,536(2):2200180
Standard sirens have been the central paradigm in gravitational-wave cosmology so far. From the gravitational wave signature of compact star binaries, it is possible to measure the luminosity distance of the source directly, and if additional information on the source redshift is provided, a measurement of the cosmological expansion can be performed. This review article discusses several methodologies that have been proposed to use gravitational waves for cosmological studies. Methods that use only gravitational-wave signals and methods that use gravitational waves in conjunction with additional observations such as electromagnetic counterparts and galaxy catalogs will be discussed. The review also discusses the most recent results on gravitational-wave cosmology, starting from the binary neutron star merger GW170817 and its electromagnetic counterpart and finishing with the population of binary black holes, observed with the third Gravitational-wave Transient Catalog GWTC–3. 相似文献
35.
One of the most remarkable social phenomena is the formation of communities in social networks corresponding to families, friendship circles, work teams, etc. Since people usually belong to several different communities at the same time, the induced overlaps result in an extremely complicated web of the communities themselves. Thus, uncovering the intricate community structure of social networks is a non-trivial task with great potential for practical applications, gaining a notable interest in the recent years. The Clique Percolation Method (CPM) is one of the earliest overlapping community finding methods, which was already used in the analysis of several different social networks. In this approach the communities correspond to k-clique percolation clusters, and the general heuristic for setting the parameters of the method is to tune the system just below the critical point of k-clique percolation. However, this rule is based on simple physical principles and its validity was never subject to quantitative analysis. Here we examine the quality of the partitioning in the vicinity of the critical point using recently introduced overlapping modularity measures. According to our results on real social and other networks, the overlapping modularities show a maximum close to the critical point, justifying the original criteria for the optimal parameter settings. 相似文献
36.
Kárpáti Levente Hamar Gergely Vargha Viktória 《Journal of Thermal Analysis and Calorimetry》2019,136(2):737-747
Journal of Thermal Analysis and Calorimetry - Random amino-alcohol-based poly(ester amide)s were synthesized using adipic acid and differently substituted amino-alcohols, namely 2-amino-ethan-1-ol,... 相似文献
37.
Attila Dénes Yoshiaki Muroya Gergely Röst 《Mathematical Methods in the Applied Sciences》2020,43(17):9671-9680
We study the global stability of a multistrain SIS model with superinfection and patch structure. We establish an iterative procedure to obtain a sequence of threshold parameters. By a repeated application of a result by Takeuchi et al. [Nonlinear Anal Real World Appl. 2006;7:235–247], we show that these parameters completely determine the global dynamics of the system: for any number of patches and strains with different infectivities, any subset of the strains can stably coexist depending on the particular choice of the parameters. 相似文献
38.
39.
Monte Carlo simulations in the NpT ensembles have been performed for the structure exploration of aqueous 1,4-dioxane solutions. Three different systems with all-atom dioxane:TIP4P water molar compositions of 2:500 (code:D2), 8:465 (D8), and 17:425 (D17) modeled solutions of 0.22, 0.88, and 1.86 mol/dm3 concentrations, respectively, at T = 298 K and p = 1 atm. The calculated solution densities increase from 0.992 to 1.002 g/cm3 with increasing dioxane concentration and approach the experimentally determined densities within 1%. This close agreement was achieved by utilizing RESP charges fitted to the in-solution IEF-PCM/B3LYP/6-31G* electrostatic potential of dioxane taken in its chair conformation and recently developed C, H steric parameters for ethers for calculations with a 12-6-1 all-atom potential. Solution structure analyses pointed out that the dioxane molecules arrange in the solutions with favorable distances of 4-8 angstroms for the ring symmetry centers. Within this range not only pairs of rings but triangular triads and tetrads have also been observed with center-center distances <8 angstroms. For the D8 system, about 25% of the sampled configurations included such a triad. In the case of the D17 model, two simulations starting from different solution configuration predicted different degrees for the dioxane aggregation in aqueous solution. In the more aggregated structure 3-21 triads are consistently maintained and 1-2 tetrads are formed in 58% of the configurations. Each dioxane oxygen forms about one hydrogen bond, on average, to a water molecule in the 0.22-1.86 molar range. The most likely O(dioxane)...H(water) hydrogen bond distance is 1.75-1.80 angstroms compared to the optimal distance of 1.72 angstroms in the isolated dimer. The optimal dioxane-water interaction energy of -5.65 kcal/mol indicates a remarkable hydrogen-bond acceptor character for dioxane. 相似文献
40.
Synthesis and Characterization of GaIII,YIII, and LuIII Complexes with Etifenin and Analogues
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Michel Pfeifer‐Leeg Gergely Szabó Zsolt Baranyai Tobias Niksch Wolfgang Weigand Martin Freesmeyer 《无机化学与普通化学杂志》2016,642(6):486-491
Complexes of etifenin ( 1a ), disofenin ( 1b ), and mebrofenin ( 1c ) with GaIII, YIII, and LuIII were synthesized and characterized by NMR spectroscopy and UV/Vis spectroscopy. Stability and protonation constants of the complexes of 1a were determined by potentiometry and distribution diagrams were calculated. It was shown that the YIII and LuIII species are most stable as bis chelates at higher pH, whereas the GaIII complex degrades at pH < 4.5. 相似文献