105 research outputs found
Efficacy of cimetidin in the prevention of ulcer formation in the stomach during immobilization stress
The effect of stress on the formation of ulcers in the mucous membrane of the stomach, the increase in cyclic adenosine monophosphate level in the gastric tissues, and parietal cell structure alteration. Use of cimetidin prevents these effect
Thermal radiation and near-field energy density of thin metallic films
We study the properties of thermal radiation emitted by a thin dielectric
slab, employing the framework of macroscopic fluctuational electrodynamics.
Particular emphasis is given to the analytical construction of the required
dyadic Green's functions. Based on these, general expressions are derived for
both the system's Poynting vector, describing the intensity of propagating
radiation, and its energy density, containing contributions from
non-propagating modes which dominate the near-field regime. An extensive
discussion is then given for thin metal films. It is shown that the radiative
intensity is maximized for a certain film thickness, due to Fabry-Perot-like
multiple reflections inside the film. The dependence of the near-field energy
density on the distance from the film's surface is governed by an interplay of
several length scales, and characterized by different exponents in different
regimes. In particular, this energy density remains finite even for arbitrarily
thin films. This unexpected feature is associated with the film's low-frequency
surface plasmon polariton. Our results also serve as reference for current
near-field experiments which search for deviations from the macroscopic
approach
Shape-dependence of near-field heat transfer between a spheroidal nanoparticle and a flat surface
We study the radiative heat transfer between a spheroidal metallic
nanoparticle and a planar metallic sample for near- and far-field distances. In
particular, we investigate the shape dependence of the heat transfer in the
near-field regime. In comparison with spherical particles, the heat transfer
typically varies by factors between 1/2 and 2 when the particle is deformed
such that its volume is kept constant. These estimates help to quantify the
deviation of the actual heat transfer recorded by a near-field scanning thermal
microscope from the value provided by a dipole model which assumes a perfectly
spherical sensor
Thermal heat radiation, near-field energy density and near-field radiative heat transfer of coated materials
We investigate the thermal radiation and thermal near-field energy density of
a metal-coated semi-infinite body for different substrates. We show that the
surface polariton coupling within the metal coating leads to an enhancement of
the TM-mode part of the thermal near-field energy density when a polar
substrate is used. In this case the result obtained for a free standing metal
film is retrieved. In contrast, in the case of a metal substrate there is no
enhancement in the TM-mode part, as can also be explained within the framework
of surface plasmon coupling within the coating. Finally, we discuss the
influence of the enhanced thermal energy density on the near-field radiative
heat transfer between a simple semi-infinite and a coated semi-infinite body
for different material combinations
Dissipative Van der Waals interaction between a small particle and a metal surface
We use a general theory of the fluctuating electromagnetic field to calculate
the friction force acting on a small neutral particle, e.g., a physisorbed
molecule, or a nanoscale object with arbitrary dispersive and absorptive
dielectric properties, moving near a metal surface. We consider the dependence
of the electromagnetic friction on the temperature , the separation , and
discuss the role of screening, non-local and retardation effects. We find that
for high resistivity materials, the dissipative van der Waals interaction can
be an important mechanism of vibrational energy relaxation of physisorbed
molecules, and friction for microscopic solids. Several controversial topics
related to electromagnetic dissipative shear stress is considered. The problem
of local heating of the surface by an STM tip is also briefly commented on.Comment: 11 pages, No figure
Magnetic phase diagram and transport properties of FeGe_2
We have used resistivity measurements to study the magnetic phase diagram of
the itinerant antiferromagnet FeGe_2 in the temperature range from 0.3->300 K
in magnetic fields up to 16 T. In contrast to theoretical predictions, the
incommensurate spin density wave phase is found to be stable at least up to 16
T, with an estimated critical field \mu _0H_c of ~ 30 T. We have also studied
the low temperature magnetoresistance in the [100], [110], and [001]
directions. The transverse magnetoresistance is well described by a power law
for magnetic fields above 1 T with no saturation observed at high fields. We
discuss our results in terms of the magnetic structure and the calculated
electronic bandstructure of FeGe_2. We have also observed, for the first time
in this compound, Shubnikov-de Haas oscillations in the transverse
magnetoresistance with a frequency of 190 +- 10 T for a magnetic field along
[001].Comment: 13 pages, RevTeX, 7 postscript figures, to appear in Journal of
Physics: Condensed Matte
ВНУТРИПОЛОСТНАЯ ТЕРАПИЯ ОЗОНИРОВАННЫМ АНТИСЕПТИЧЕСКИМ РАСТВОРОМ В КОМПЛЕКСНОМ ЛЕЧЕНИИ ПАЦИЕНТОВ С ИНФИЦИРОВАННЫМИ ПОЛОСТНЫМИ ОБРАЗОВАНИЯМИ ПЕЧЕНИ
Application in the treatment of patients with infected cavitary formations liver intracavitary therapy ozonated antiseptic allowed significantly speed up the recovery of liver function, reduce the time of hospital treatment, to accelerate the elimination of the abscess cavity.Применение в лечении у пациентов с инфицированными полостными образованиями печени внутриполостной терапии озонированным антисептическим раствором позволило достоверно ускорить восстановление функции печени, уменьшить сроки стационарного лечения, ускорить ликвидацию полости абсцесса
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