853 research outputs found
Poynting vector, energy density and energy velocity in anomalous dispersion medium
The Poynting vector, energy density and energy velocity of light pulses
propagating in anomalous dispersion medium (used in WKD-like experiments) are
calculated. Results show that a negative energy density in the medium
propagates along opposite of incident direction with such a velocity similar to
the negative group velocity while the direction of the Poynting vector is
positive. In other words, one might say that a positive energy density in the
medium would propagate along the positive direction with a speed having
approximately the absolute valueof the group velocity. We further point out
that neither energy velocity nor group velocity is a good concept to describe
the propagation process of light pulse inside the medium in WKD experiment
owing to the strong accumulation and dissipation effects.Comment: 6 page
OL-018 Efficacy of interferon for chronic hepatitis B patients with normal or paranormal ALT
Synthesis, Superhydrophobicity, Enhanced Photoluminescence and Gas Sensing Properties of ZnO Nanowires
Gravitational time advancement and its possible detection
The gravitational time advancement is a natural but a consequence of curve
space-time geometry. In the present work the expressions of gravitational time
advancement have been obtained for geodesic motions. The situation when the
distance of signal travel is small in comparison to the distance of closest
approach has also been considered. The possibility of experimental detection of
time advancement effect has been explored.Comment: 5 pages, 4 figures, a part of the work has been changed in the
revised versio
Two dimensional scaling of resistance in flux flow region in thin films
The resistance of thin films has been measured when the
angle between the applied fields and -plane of the film is changed
continuously at various temperatures. Under various magnetic fields, the
resistance can be well scaled in terms of the c-axis component of the applied
fields at the same temperature in the whole angle range. Meanwhile, we show
that the measurement of resistance in this way is a complementary method to
determine the growth orientation of the anisotropic high- superconductors.Comment: 11 pages, 8 figures. Have been published in Physica
Correlation between muonic levels and nuclear structure in muonic atoms
A method that deals with the nucleons and the muon unitedly is employed to
investigate the muonic lead, with which the correlation between the muon and
nucleus can be studied distinctly. A "kink" appears in the muonic isotope shift
at a neutron magic number where the nuclear shell structure plays a key role.
This behavior may have very important implications for the experimentally
probing the shell structure of the nuclei far away from the -stable
line. We investigate the variations of the nuclear structure due to the
interaction with the muon in the muonic atom and find that the nuclear
structure remains basically unaltered. Therefore, the muon is a clean and
reliable probe for studying the nuclear structure. In addition, a correction
that the muon-induced slight change in the proton density distribution in turn
shifts the muonic levels is investigated. This correction to muonic level is as
important as the Lamb shift and high order vacuum polarization correction, but
is larger than anomalous magnetic moment and electron shielding correction.Comment: 2 figure
Time-lagged study on psychological contract breach, perceived organizational support and turnover intention of general practitioners
Objective To analyze teh relationship between perceived organizational support, psychological contract breach and turnover intention, so dat to provide a new idea for teh improvement of incentives for general practitioners.
Mehtods During teh period from June to December 2016, two questionnaire surveys were conducted among teh general practitioners of teh Community Health Centers in Pudong New Area, Shanghai. Teh first survey measured demographic sociology information, perceived organizational support, and psychological contract breach. Teh second survey measured turnover intention. Data analysis was performed using SPSS 24.0 and AMOS 24.0 statistical software.
Results 1145 GPs got score of 4.59±0.85 in perceived organizational support, score of 2.87±0.53 in psychological contract breach, and score of 2.26±0.95 in turnover intention. Psychological contract breach and perceived organizational support had a negative effect on turnover intention, and psychological contract breach had a positive effect on perceived organizational support, and perceived organizational support had a partial mediation role in psychological contract breach and turnover intention.
Conclusion Teh incentive measures for general practitioners in Pudong New Area of Shanghai need to be further improved from teh aspects of strengtaning interpretation and guaranteeing implementation, and emphasis on career development.info:eu-repo/semantics/acceptedVersio
Large scale quantum simulations: C_60 impacts on a semiconducting surface
We present tight binding molecular dynamics simulations of C_60 collisions on
the reconstructed diamond(111) surface, carried out with an O(N) method and
with cells containing 1140 atoms. The results of our simulations are in very
good agreement with experiments performed under the same impact conditions.
Furthermore our calculations provide a detailed characterization of the
microscopic processes occuring during the collision, and allow the
identification of three impact regimes, as a function of the fullerene incident
energy. Finally, the study of the reactivity between the cluster and the
surface gives insight into the deposition mechanisms of C_60 on semiconducting
substrates
Multiplexing radiography using a carbon nanotube based x-ray source
Speed and temporal resolution are critical for tomographic imaging of objects in rapid motion. Current x-ray scanners record images sequentially in the time domain. The serial approach limits their performance and demands increasingly high x-ray peak power and gantry speed. We have developed a multipixel carbon nanotube based field emission x-ray source that produces spatially and temporally modulated radiations. Using this device we show the feasibility of multiplexing radiography that enables simultaneous collection of multiple projection images using frequency multiplexing. A drastic increase of the speed and reduction of the x-ray peak power are achieved without compromising the imaging quality
Epitaxial growth of atomically flat gadolinia-doped ceria thin films by pulsed laser deposition
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