16,265 research outputs found
Optical properties of in the normal state
We present the optical reflectance and conductivity spectra for non-oxide
antiperovskite superconductor at different temperatures. The
reflectance drops gradually over a large energy scale up to 33,000 cm,
with the presence of several wiggles. The reflectance has slight temperature
dependence at low frequency but becomes temperature independent at high
frequency. The optical conductivity shows a Drude response at low frequencies
and four broad absorption features in the frequency range from 600 to
33,000 . We illustrate that those features can be well understood from
the intra- and interband transitions between different components of Ni 3d
bands which are hybridized with C 2p bands. There is a good agreement between
our experimental data and the first-principle band structure calculations.Comment: 4 pages, to be published in Phys. Rev.
The hyperon mean free paths in the relativistic mean field
The - and -hyperon mean free paths in nuclei are firstly
calculated in the relativistic mean field (RMF) theory. The real parts of the
optical potential are derived from the RMF approach, while the imaginary parts
are obtained from those of nucleons with the relations:
and . With the
assumption, the depth of the imaginary potential for is
3.5 MeV, and for is 7 MeV at
low incident energy. We find that, the hyperon mean free path decreases with
the increase of the hyperon incident energies, from 200 MeV to 800 MeV; and in
the interior of the nuclei, the mean free path is about fm for
, and about fm for , depending on the hyperon
incident energy.Comment: 5 figures, 6 page
Construction of high-density genetic map in barley through restriction-site associated DNA sequencing
Genetic maps in barley are usually constructed from a limited number of molecular markers such as SSR (simple sequence repeat) and DarT (diversity arrays technology). These markers must be first developed before being used for genotyping. Here, we introduce a new strategy based on sequencing progeny of a doubled haploid population from Baudin × AC Metcalfe to construct a genetic map in barley. About 13,547 polymorphic SNP tags with >93% calling rate were selected to construct the genetic map. A total of 12,998 SNP tags were anchored to seven linkage groups which spanned a cumulative 967.6 cM genetic distance. The high-density genetic map can be used for QTL mapping and the assembly of WGS and BAC contigs. The genetic map was evaluated for its effectiveness and efficiency in QTL mapping and candidate gene identification. A major QTL for plant height was mapped at 105.5 cM on chromosome 3H. This QTL with LOD value of 13.01 explained 44.5% of phenotypic variation. This strategy will enable rapid and efficient establishment of high-density genetic maps in other species
Kinetics analysis of solidification process of 1035 steel at different cooling rates
It is of great theoretical significance to study the solidification kinetics of metal materials for improving the microstructure and properties. In this paper, the Differential Scanning Calorimetry (DSC) was used to measure the enthalpy change of solidification process of 1035 steel at different cooling rates. The activation energy of the solidification process was determined by the equal conversion method based on the data of enthalpy. The mechanism function of the solidification process was also determined. It is shown that the value of the activation energy of solidification process varied with the solidification fraction, and the mechanism functions of solidification process are different in different temperature ranges, which are –ln(1– α) for 1 504-1 502 °C –ln(1–α)1/2 for 1 500-1 942 °C and –ln(1– α)2/5 for_1 490 °C respectively
Cardiac rhythm analysis during ongoing cardiopulmonary resuscitation using the Analysis During Compressions with Fast reconfirmation technology
BACKGROUND Pauses in chest compressions (CCs) have a negative association with survival from cardiac arrest. Electrocardiographic (ECG) rhythm analysis and defibrillator charging are significant contributors to CC pauses.
OBJECTIVE Accuracy of the Analysis During Compressions with Fast Reconfirmation (ADC-FR) algorithm, which features automated rhythm analysis and charging during CCs to reduce CC pauses, was retrospectively determined in a large database of ECGs from 2701 patients with out-of-hospital cardiac arrest.
METHODS The ADC-FR algorithm generated a total of 7264 advisories, of which 3575 were randomly assigned to a development data set and 3689 to a test data set. With ADC-FR, a high-pass digital filter is used to remove CC artifacts, while the underlying ECG rhythm is automatically interpreted. When CCs are paused at the end of the 2-minute cardiopulmonary resuscitation interval, a 3-second reconfirmation analysis is performed using the artifact-free ECG to confirm the shock/no-shock advisory. The sensitivity and specificity of the ADC-FR algorithm in correctly identifying shockable/nonshockable rhythms during CCs were calculated.
RESULTS In both data sets, the accuracy of the ADC-FR algorithm for each ECG rhythm exceeded the recommended performance goals, which apply to a standard artifact-free ECG analysis. Sensitivity and specificity were 97% and 99%, respectively, for the development data set and 95% and 99% for the test data set.
CONCLUSION The ADC-FR algorithm is highly accurate in discriminating shockable and nonshockable rhythms and can be used to reduce CC pauses
Evolution of InAs branches in InAs/GaAs nanowire heterostructures
Branched nanowireheterostructures of InAs∕GaAs were observed during Au-assisted growth of InAs on GaAsnanowires. The evolution of these branches has been determined through detailed electron microscopy characterization with the following sequence: (1) in the initial stage of InAsgrowth, the Au droplet is observed to slide down the side of the GaAsnanowire, (2) the downward movement of Aunanoparticle later terminates when the nanoparticle encounters InAsgrowing radially on the GaAsnanowire sidewalls, and (3) with further supply of In and As vapor reactants, the Aunanoparticles assist the formation of InAs branches with a well-defined orientation relationship with GaAs∕InAs core/shell stems. We anticipate that these observations advance the understanding of the kink formation in axial nanowireheterostructures.The Australian Research Council is acknowledged for
the financial support of this project. One of the authors
M.P. acknowledges the support of an International Postgraduate
Research Scholarship
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