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The effects of k-dependent self-energy in the electronic structure of correlated materials
It is known from self-energy calculations in the electron gas and sp
materials based on the GW approximation that a typical quasiparticle
renormalization factor (Z factor) is approximately 0.7-0.8. Band narrowing in
electron gas at rs = 4 due to correlation effects, however, is only
approximately 10%, significantly smaller than the Z factor would suggest. The
band narrowing is determined by the frequency-dependent self-energy, giving the
Z factor, and the momentum-dependent or nonlocal self-energy. The results for
the electron gas point to a strong cancellation between the effects of
frequency- and momentum-dependent self-energy. It is often assumed that for
systems with a nar- row band the self-energy is local. In this work we show
that even for narrow-band materials, such as SrVO3, the nonlocal self-energy is
important.Comment: 7 pages, 6 figure
CHANGES IN FORCE-LENGTH RELATIONSHIP OF TRICEPS SURAE MUSCLES AFTER REPEATED ECCENTRIC-CONCENTRIC EXERCISES
INTRODUCTION: Postexercise muscle soreness develops gradually 24 to 48 hours after an eccentric exercise. The prolonged reduction of maximal voluntary force also occurs after eccentric exercise (Nosaka et al, 1991). The reduction in maximal force is thought to be due to peripheral muscle damage derived by eccentric lengthening, but the exact mechanisms are yet to be discovered. One possibility of the reduction in force is the shifting of the optimal length for force production (Prasartwuth et al. 2006). In this study we tested this possibility for the human triceps surae muscles
CHARACTERISTIC OF (AgI)0.44 (LiI)0.22 (AgPO3)0.34 IONIC CONDUCTOR PREPARED BY MELT QUENCHING METHOD
CHARACTERISTIC OF (AgI)0.44 (LiI)0.22 (AgPO3)0.34 IONIC CONDUCTOR PREPARED BY MELT QUENCHING METHOD. Characterization of (AgI)0.44 (LiI)0.22 (AgPO3)0.34 ionic conductor prepared by melt quenching method have been carried out by using X-RayDiffractometer (XRD), Differential Scanning Calorimeter (DSC) and Inductance (L) Capacitance (C) Resistance (R) meter. X-ray diffraction pattern shows that the compound has a mixture of amorphous and small amount of crystalline formwith several Bragg peaks correspond toAgI. The DSC thermograph shows that an endothermic peak at temperature ~420 K matches with the phase transition ofAgI which reinforces that a number ofAgI are not dissolved in the material of (AgI)0.44 (LiI)0.22 (AgPO3)0.34 . The obtained dc ionic conductivity is around ~10-2 S/cmat ambient temperature. The activation energy has two values, 0.20 eV below ~380 K and 0.15 eV above ~380 K
Segmented scintillation detectors with silicon photomultiplier readout for measuring antiproton annihilations
The Atomic Spectroscopy and Collisions Using Slow Antiprotons (ASACUSA)
experiment at the Antiproton Decelerator (AD) facility of CERN constructed
segmented scintillators to detect and track the charged pions which emerge from
antiproton annihilations in a future superconducting radiofrequency Paul trap
for antiprotons. A system of 541 cast and extruded scintillator bars were
arranged in 11 detector modules which provided a spatial resolution of 17 mm.
Green wavelength-shifting fibers were embedded in the scintillators, and read
out by silicon photomultipliers which had a sensitive area of 1 x 1 mm^2. The
photoelectron yields of various scintillator configurations were measured using
a negative pion beam of momentum p ~ 1 GeV/c. Various fibers and silicon
photomultipliers, fiber end terminations, and couplings between the fibers and
scintillators were compared. The detectors were also tested using the
antiproton beam of the AD. Nonlinear effects due to the saturation of the
silicon photomultiplier were seen at high annihilation rates of the
antiprotons.Comment: Copyright 2014 American Institute of Physics. This article may be
downloaded for personal use only. Any other use requires prior permission of
the author and the American Institute of Physics. The following article
appeared in Review of Scientific Instruments, Vol.85, Issue 2, 2014 and may
be found at http://dx.doi.org/10.1063/1.486364
Characteristic of (Agi)0.44 (Lii)0.22 (Agpo3)0.34 Ionic Conductor Prepared by Melt Quenching Method
CHARACTERISTIC OF (AgI)0.44 (LiI)0.22 (AgPO3)0.34 IONIC CONDUCTOR PREPARED BY MELT QUENCHING METHOD. Characterization of (AgI)0.44 (LiI)0.22 (AgPO3)0.34 ionic conductor prepared by melt quenching method have been carried out by using X-RayDiffractometer (XRD), Differential Scanning Calorimeter (DSC) and Inductance (L) Capacitance (C) Resistance (R) meter. X-ray diffraction pattern shows that the compound has a mixture of amorphous and small amount of crystalline formwith several Bragg peaks correspond toAgI. The DSC thermograph shows that an endothermic peak at temperature ~420 K matches with the phase transition ofAgI which reinforces that a number ofAgI are not dissolved in the material of (AgI)0.44 (LiI)0.22 (AgPO3)0.34 . The obtained dc ionic conductivity is around ~10-2 S/cmat ambient temperature. The activation energy has two values, 0.20 eV below ~380 K and 0.15 eV above ~380 K
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