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101.
We study the low energy properties of warped monolayer graphene, where the symmetry of the original honeycomb lattice reveals itself. The zero energy solutions are Majorana fermions, whose wave function, originating from the corresponding modified Dirac equation is spatially localized. Experimental consequences are discussed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
102.
This paper contains two results on influence in collective decision games. The first part deals with general perfect information coin-flipping games as defined in [3].Baton passing (see [8]), ann-player game from this class is shown to have the following property: IfS is a coalition of size at most \(\frac{n}{{3\log n}}\) , then the influence ofS on the game is only \(O\left( {\frac{{\left| S \right|}}{n}} \right)\) . This complements a result from [3] that for everyk there is a coalition of sizek with influence Ω(k/n). Thus the best possible bounds on influences of coalitions of size up to this threshold are known, and there need not be coalitions up to this size whose influence asymptotically exceeds their fraction of the population. This result may be expected to play a role in resolving the most outstanding problem in this area: Does everyn-player perfect information coin flipping game have a coalition ofo(n) players with influence 1?o(1)? (Recently Alon and Naor [1] gave a negative answer to this question.) In a recent paper Kahn, Kalai and Linial [7] showed that for everyn-variable boolean function of expectation bounded away from zero and one, there is a set of \(\frac{{n\omega (n)}}{{\log n}}\) variables whose influence is 1?o(1), wherew(n) is any function tending to infinity withn. They raised the analogous question where 1?o(1) is replaced by any positive constant and speculated that a constant influence may be always achievable by significantly smaller sets of variables. This problem is almost completely solved in the second part of this article where we establish the existence of boolean functions where only sets of at least \(\Omega \left( {\frac{n}{{\log ^2 n}}} \right)\) variables can have influence bounded away from zero. 相似文献
103.
Let {X,Xn,n1} be a sequence of independent identically distributed random variables with EX=0 and assume that EX2I(|X|≤x) is slowly varying as x→∞,i.e.,X is in the domain of attraction of the normal law.In this paper a Strassen-type strong approximation is established for self-normalized sums of such random variables. 相似文献
104.
A discrete-time financial market model is considered with a sequence of investors whose preferences are described by concave strictly increasing functions defined on the positive axis. Under suitable conditions, we show that the utility indifference prices of a bounded contingent claim converge to its superreplication price when the investors’ absolute risk-aversion tends to infinity. 相似文献
105.
106.
György Gergely Miklós Menyhard Attila Sulyok Sándor Gurban Beata Lesiak Aleksander Jablonski Andrzej Kosinski József Toth Dezső Varga 《Central European Journal of Physics》2007,5(2):188-200
The inelastic mean free path (IMFP) of electrons was determined experimentally for selected polyaniline and polyacetylene
samples with Ag and Ni references using elastic peak electron spectroscopy (EPES). The surface composition was determined
by XPS and density by helium pycnometry. The high resolution hemispherical ESA-31 and ADES-400 spectrometers were used for
measurements in the energy range E = 0.5–3.0 keV and E =0.4 − 1.6 keV, respectively. The integrated elastic peak intensity ratios for sample and reference were calculated using
the Monte Carlo (MC) algorithm based on the electron elastic scattering cross-sections database NIST SRD64 version 3.1 and
applying TPP-2M IMFPs for polymers. Surface excitation parameters (SEP) and material parameters (
ach
) for polymers were determined, using the model of Chen, from comparison of measured and MC calculated elastic peak intensity
ratios. These corrections proved to be efficient in decreasing the percentage deviations between the obtained IMFPs and the
TPP-2M formula IMFPs. The elastic peak of hydrogen was observed in the EPES spectra of polymers. The experimental contribution
of the hydrogen to the total elastic peak was 0.58%, while this value obtained from the MC simulations was 1.98%.
相似文献
107.
Seres J Müller A Seres E O'Keeffe K Lenner M Herzog RF Kaplan D Spielmann C Krausz F 《Optics letters》2003,28(19):1832-1834
A three-stage, 1-kHz amplifier system delivering pulses shorter than 10 fs with a peak power in excess of 0.3 TW is reported. Passive and active spectral intensity and phase control allows the preservation of a bandwidth of 120 nm (FWHM) to as high as multimillijoule energy levels and temporal compression of the broadband pulses close to their Fourier limit. The system is scalable to peak powers well beyond 1 TW and holds promise for substantially advancing the state of the art of coherent laboratory soft-x-ray sources. 相似文献
108.
109.
Monika Zagyi Esther Forgács Miklós Prodan Tibor Cserháti Dusan Berek 《Analytical sciences》2003,19(2):245-248
The strength and the character of the binding of 12 organic solvents to the corn protein zein was determined by preparing zein-coated carbon stationary phase and by measuring the retention of solvents on a high-performance liquid chromatographic column filled with this stationary phase. The relationship between the physicochemical parameters and binding characteristics of solvents was elucidated by principal component analysis. Various interactive forces are involved in the binding of solvent to the protein. The strength of the binding is dominantly influenced by the molecular hydrophobicity while the Gaussian or non-Gaussian distribution of the adsorption strength is markedly dependent on the polarity parameters of the solvent. Sterical correspondences exerted considerable influence on each binding parameter. 相似文献
110.
The correlation between the syn-anti geometry and circular dichroism of several O-benzyl or O-isopropyl substituted steroidoximes 1–22 was investigated. A simple sector rule was found for the longest wavelength CD band of the unsaturated oximes 1–13. The correlations are not so clear for the unsaturated derivatives 14–22. 相似文献