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991.
Alexander Bass Seth Putterman Barry Merriman Steven J. Ruuth 《Journal of computational physics》2008,227(3):2118-2129
We propose a symmetry reduction technique whereby molecular dynamics (MD) simulations for spherically symmetric gas bubbles can be accelerated. Results for an imploding Xenon bubble containing 50 million particles—the smallest measured sonoluminescing system—are presented. 相似文献
992.
Strongly correlated systems far from equilibrium can exhibit scaling solutions with a dynamically generated weak coupling. We show this by investigating isolated systems described by relativistic quantum field theories for initial conditions leading to nonequilibrium instabilities, such as parametric resonance or spinodal decomposition. The nonthermal fixed points prevent fast thermalization if classical-statistical fluctuations dominate over quantum fluctuations. We comment on the possible significance of these results for the heating of the early Universe after inflation and the question of fast thermalization in heavy-ion collision experiments. 相似文献
993.
994.
Artuso M Blusk S Butt J Li J Menaa N Mountain R Nisar S Randrianarivony K Sia R Skwarnicki T Stone S Wang JC Zhang K Bonvicini G Cinabro D Dubrovin M Lincoln A Asner DM Edwards KW Naik P Briere RA Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Cassel DG Duboscq JE Ehrlich R Fields L Galik RS Gibbons L Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE Mahlke-Krüger H Mohapatra D Onyisi PU Patterson JR Peterson D Pivarski J 《Physical review letters》2007,99(19):191801
Using a 281 pb{-1} data sample collected at the psi(3770) with the CLEO-c detector, we present the first absolute branching fraction measurement of the decay D0-->K(-)pi(+)pi(-)e(+)nu(e) at a statistical significance of about 4.0 standard deviations. We find 10 candidates consistent with the decay D0-->K(-)pi(+)pi(-)e(+)nu(e). The probability that a background fluctuation accounts for this signal is less than 4.1 x 10{-5}. We find B(D0-->K(-)pi(+)pi(-)e(+)nu(e)) = [2.8{-1.1}{+1.4}(stat)+/-0.3(syst)]x10{-4}. By restricting the invariant mass of the hadronic system to be consistent with K1(1270), we obtain the product of branching fractions B(D{0}-->K{1}{-}(1270)e{+}nu{e})xB(K1-(1270)-->K{-}pi{+}pi{-})=[2.5{-1.0}{+1.3}(stat)+/-0.2(syst)]x10{-4}. Using B(K1-(1270)-->K{-}pi{+}pi{-})=(33+/-3)%, we obtain B(D{0}-->K{1}{-}(1270)e{+}nu{e})=[7.6{-3.0}{+4.1}(stat)+/-0.6(syst)+/-0.7]x10{-4}. The last error accounts for the uncertainties in the measured K1-(1270)-->K{-}pi{+}pi{-} branching fractions. 相似文献
995.
Stutzki F Jansen F Eidam T Steinmetz A Jauregui C Limpert J Tünnermann A 《Optics letters》2011,36(5):689-691
Ytterbium-doped large-pitch fibers with very large mode areas are investigated in a high-power fiber amplifier configuration. An average output power of 294?W is demonstrated, while maintaining robust single-mode operation with a mode field diameter of 62?μm. Compared to previous active large-mode area designs, the threshold of mode instabilities is increased by a factor of about 3. 相似文献
996.
New trinuclear gadolinium(III) complex having 2-bromoisovaleric acid pendant arm is reported. The longitudinal relaxivity (r 1p) of the complex is 23.17 mM?1 s?1 which correspond to a “per Gd” relaxivity of 7.72 mM?1 s?1. The transverse relaxivity (r 2p) of the complex is 24.79 mM?1 s?1 which correspond to a “per Gd” value of 8.26. The complex exhibit r 1p and r 2p values of 29.19 and 35.20, respectively, in the presence of HSA. The complex also shows pH dependant relaxivity which is an added advantage of the complex for utilization in cancer cell magnetic resonance imaging. The higher relaxivity values in water and HSA indicates a compact solution structure for the complexes and a restricted internal motion about the amide spacer. 相似文献
997.
We evaluate accelerator science in the context of its contributions to the physics community. We address the problem of quantifying
these contributions and present a scheme for a numerical evaluation of them. We show by using a statistical sample of important
developments in modern physics that accelerator science has influenced 28% of post-1938 physicists and also 28% of post-1938
physics research. We also examine how the influence of accelerator science has evolved over time, and show that on average
it has contributed to a physics Nobel Prize-winning research every 2.9 years. 相似文献
998.
Shadow effects in spiral phase contrast microscopy 总被引:3,自引:0,他引:3
Recently it has been demonstrated that spatial filtering of images in microscopy with a spiral phase element in a Fourier plane of the optical path results in a strong edge enhancement of object structures. In principle the operation is isotropic, i.e., all phase edges of a sample object are highlighted simultaneously, independent of their local direction. However, here we demonstrate that the symmetry can be broken intentionally by controlling the phase of the central area of a spiral phase hologram, which is displayed at a computer controlled spatial light modulator. This produces an apparent shadow effect which can be rotated at video rate. The resulting relieflike impression of the sample topography with a longitudinal resolution in the subwavelength regime is demonstrated by imaging a standard low contrast test sample consisting of a human cheek cell. 相似文献
999.
1000.
Comparative characterization of thermal isomerization rates of 6‐phenyl‐1,5‐diazabicyclo[3.1.0]hexane at convection and microwave heating 下载免费PDF全文
Tatiana A. Kornilova Rafael R. Kostikov Alexander F. Khlebnikov Igor G. Zenkevich 《Journal of Physical Organic Chemistry》2018,31(7)
Rate constants of thermal isomerization of 6‐phenyl‐1,5‐diazabicyclo[3.1.0]hexane into 1‐(benzyl)‐4,5‐dihydro‐1H‐pyrazole at convection and microwave heating in toluene and chlorobenzene (solvents) were determined within the temperature range 90°C to 120°С. These data were used for the calculation of activation parameters of isomerization. It is shown that microwave heating increases the rate constants at the same temperature by a factor of 2 to 2.5 as compared with those using convection heating. The reason is that the effective temperature of microwave heating exceeds that of convection heating by 6°C to 9°С in toluene and by 12°C to 20°С in chlorobenzene as solvent. 相似文献