24,266 research outputs found
Synthesis of PbS nanocrystallites using a novel single molecule precursors approach: X-ray single-crystal structure of Pb(S2CNEtPri)2
The synthesis and characterisation of some lead(II) dithiocarbamato complexes Pb(S2CNRR¾)2 is reported. These compounds were
used as single molecule precursors to produce nanocrystalline PbS by their thermolysis in trioctylphosphine oxide. The optical and
morphological properties of the resulting PbS nanocrystallites were investigated; the influence of experimental parameters, such as
precursor, growth time and temperature, on the final nanodispersed materials is also reported
Strange sea asymmetry in nucleons
We evaluate the medium effects in nucleon which can induce an asymmetry of
the strange sea. The short-distance effects determined by the weak interaction
can give rise to where is the medium-induced mass of strange quark by a few KeV at
most, but the long-distance effects by strong interaction could be sizable.Comment: 4 pages and no figures, Talk presented at the Third
Circum-Pan-Pacific Symposium on "High Energy Spin Physics", Oct. 8-13, 2001,
Beijing, Chin
Fine Splitting in Charmonium Spectrum with Channel Coupling Effect
We study the fine splitting in charmonium spectrum in quark model with the
channel coupling effect, including , , and ,
, channels. The interaction for channel coupling is
constructed from the current-current Lagrangian related to the color
confinement and the one-gluon exchange potentials. By adopting the massive
gluon propagator from the lattice calculation in the nonperturbative region,
the coupling interaction is further simplified to the four-fermion interaction.
The numerical calculation still prefers the assignment of X(3872).Comment: Submitted to Chinese Physics
Relay Backpropagation for Effective Learning of Deep Convolutional Neural Networks
Learning deeper convolutional neural networks becomes a tendency in recent
years. However, many empirical evidences suggest that performance improvement
cannot be gained by simply stacking more layers. In this paper, we consider the
issue from an information theoretical perspective, and propose a novel method
Relay Backpropagation, that encourages the propagation of effective information
through the network in training stage. By virtue of the method, we achieved the
first place in ILSVRC 2015 Scene Classification Challenge. Extensive
experiments on two challenging large scale datasets demonstrate the
effectiveness of our method is not restricted to a specific dataset or network
architecture. Our models will be available to the research community later.Comment: Technical report for our submissions to the ILSVRC 2015 Scene
Classification Challenge, where we won the first plac
Non linear flux flow in TiN superconducting thin film
We have studied the superconducting behavior of 100 nm Titanium Nitride (TiN)
thin film in a perpendicular magnetic field. We found a zero field transition
temperature of 4.6 K and a slope in the H-T plane of -0.745 T/K. At 4.2 K, we
have performed careful transport measurements by measuring both the
differential resistivity and voltage as a function of a DC current. Our results
are analyzed in the framework of linear and non linear flux flow behavior. In
particular, we have observed an electronic instability at high vortex
velocities and from its dependence with respect to the applied magnetic field,
we can exctract the inelastic scattering time and diffusion length of the
quasiparticles
Theoretical prediction of topological insulator in ternary rare earth chalcogenides
A new class of three-dimensional topological insulator, ternary rare earth
chalcogenides, is theoretically investigated with ab initio calculations. Based
on both bulk band structure analysis and the direct calculation of topological
surface states, we demonstrate that LaBiTe3 is a topological insulator. La can
be substituted by other rare earth elements, which provide candidates for novel
topological states such as quantum anomalous Hall insulator, axionic insulator
and topological Kondo insulator. Moreover, YBiTe3 and YSbTe3 are found to be
normal insulators. They can be used as protecting barrier materials for both
LaBiTe3 and Bi2Te3 families of topological insulators for their well matched
lattice constants and chemical composition.Comment: 5 pages, 3 figures and 1 tabl
On R-duals and the duality principle in Gabor analysis
The concept of R-duals of a frame was introduced by Casazza, Kutyniok and
Lammers in 2004, with the motivation to obtain a general version of the duality
principle in Gabor analysis. For tight Gabor frames and Gabor Riesz bases the
three authors were actually able to show that the duality principle is a
special case of general results for R-duals. In this paper we introduce various
alternative R-duals, with focus on what we call R-duals of type II and III. We
show how they are related and provide characterizations of the R-duals of type
II and III. In particular, we prove that for tight frames these classes
coincide with the R-duals by Casazza et el., which is desirable in the sense
that the motivating case of tight Gabor frames already is well covered by these
R-duals. On the other hand, all the introduced types of R-duals generalize the
duality principle for larger classes of Gabor frames than just the tight frames
and the Riesz bases; in particular, the R-duals of type III cover the duality
principle for all Gabor frames
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