The Casimir–Lifshitz friction force and the heating rates of two metal plates with a narrow vacuum gap between them during nonrelativistic motion of one of them are calculated within the framework of ...fluctuation electrodynamics taking into account the temperature change in material properties. It is shown that identical plates with the same initial temperature have the same heating rate, determined by the power of the friction force, and the possibility of measuring the friction force from the heating kinetics of nonmagnetic metal plates with temperatures of 1–10 K is substantiated.
The rate of radiative heating (cooling) of a metal nanoparticle moving near the surface of a metal plate at low temperatures (1–10 K) of both bodies is calculated. The dielectric properties of the ...particle and plate are described in the Drude approximation with temperature-dependent/independent relaxation frequencies of electrons. The motion of a hotter particle is shown to cause its further heating in a certain range of the temperature difference.
The van der Waals friction force (dissipative fluctuation electromagnetic force) between metallic plates during their relative motion at temperatures close to 1 K is calculated within the ...Levin–Polevoi–Rytov fluctuation electromagnetic theory. It is shown that the van der Waals friction force for gold plates with a small number of defects and low residual resistance
can increase by six to eight orders of magnitude with a decrease in the temperature below 100 K, reaching a maximum value proportional to
. For superconducting metals, an increase in friction can be observed when the temperature decreases to the critical transition temperature, after which friction disappears. Another important result is the weak dependence of the friction force on the distance
a
between the plates (
with 0 <
q
< 1). The absolute values of the friction forces are achievable for measurements in experiments using the modern atomic force microscopy technique.
•Van der waals friction and quantum friction in particle-plate and plate-plate configurations with normal metals are enhanced by 2 to 4 orders of magnitude due to spatial dispersion effects at ...separations of 1–10 nm.•Using analytical nonlocal dielectric permittivity of metals enables obtaining simple formulas for van der waals friction forces and quantum friction forces.•Within nonretarded approximation, the formulas for van der waals and quantum friction forces formally coincide with the formulas in local approximation, except the form of the surface response function.
In the nonrelativistic approximation of fluctuation electrodynamics, using the specular reflection model and the nonlocal dielectric permittivity of a metal, we obtained simple analytical expressions for the friction forces in the particle-plate and plate-plate systems upon relative motion of the bodies with constant velocity. It is shown that at separations of about 1÷10 nm, for an Au nanoparticle (or a gold plate) moving near another gold plate at rest, the dissipative forces are 2 to 4 orders of magnitude higher than in the case when the local Drude dielectric permittivity is used.
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The forces acting on a magnetic particle during nonrelativistic motion parallel to the surface of a homogeneous medium with a frequency dispersion of the magnetic permeability are considered. General ...expressions are obtained for the normal (attractive) and lateral (stopping) forces acting on a small dipole particle and an extended probe. It is shown that for an arbitrary orientation of the vector of the dipole magnetic moment of the particle, along with the force of attraction and the drag force, there also appears a velocity-dependent lateral force perpendicular to the velocity vector. The possibility of using these results to study the frequency-dependent magnetic permeability of nanostructured materials and films in the dynamic scanning mode of magnetic force microscopy (MCM) with magnetic probes is discussed. Numerical estimates are given for the magnitude of the expected forces, friction coefficients, and changes in the quality factor of the MFM oscillators in the case of frequency dispersion of the magnetic permeability of the relaxation type.
In the nonrelativistic approximation of fluctuation electrodynamics, using the specular reflection model and the nonlocal dielectric permittivity of a metal, simple analytical expressions are ...obtained for the friction forces in the particle-plate and plate-plate configurations at relative motion of bodies with constant velocity. It has been shown that at distances of about 1–10 nm, for an Au nanoparticle (or a gold plate) moving near another similar plate at rest, the dissipative forces are 2–4 orders of magnitude higher than when using the Drude local dielectric function.
It has been shown that the fundamental results obtained in the works by Levine–Polevoi–Rytov (1980) and Rytov (1990) adequately describe the rate of radiative heat exchange and frictional force in a ...system of two thick parallel plates in relative motion, in full agreement with the results obtained by other authors later. A numerically calculated friction force for Drude metals turns out to be higher by a factor of 10
7
than the early result obtained by Polevoi. In addition, the friction force significantly increases with increasing the conductivity of the plates or increasing the relaxation time of electrons with decreasing temperature.
We calculate heating rate, attractive conservative and tangential dissipative fluctuation electromagnetic forces felt by a thick plate moving with nonrelativistic velocity parallel to a closely ...spaced another plate in rest using relativistic fluctuation electrodynamics. We argue that recently developed relativistic out of equilibrium theory of fluctuation electromagnetic interactions A.I. Volokitin, B.N.J. Persson, Phys. Rev. B78 (2008) 155437;
arXiv:/cond-mat.other/0807.1004v1, 2008 has serious drawbacks.
•A real-time RT-PCR assay for EBOV (Zaire) detection was developed and evaluated.•Assay specificity was studied using a representative sampling of viral, bacterial and human RNA/DNA.•The assay ...sensitivity was 5×102 copies per ml.•52 suspected for EVD patients of Donka Hospital Conakry, Guinea, tested positive and 149 tested negative.
In early February 2014, an outbreak of the Ebola virus disease caused by Zaire ebolavirus (EBOV) occurred in Guinea; cases were also recorded in other West African countries with a combined population of approximately 25 million. A rapid, sensitive and inexpensive method for detecting EBOV is needed to effectively control such outbreak. Here, we report a real-time reverse-transcription PCR assay for Z. ebolavirus detection used by the Specialized Anti-epidemic Team of the Russian Federation during the Ebola virus disease prevention mission in the Republic of Guinea. The analytical sensitivity of the assay is 5×102 viral particles per ml, and high specificity is demonstrated using representative sampling of viral, bacterial and human nucleic acids. This assay can be applied successfully for detecting the West African strains of Z. ebolavirus as well as on strains isolated in the Democratic Republic of the Congo in 2014.
We obtained new nonrelativistic expression for the dynamical van der Waals atom–surface interaction energy of a very convenient form for different applications. It is shown that classical result ...(Ferrell and Ritchie, 1980) holds only for a very slowly moving atom. In general case, the van der Waals atom–surface interaction energy manifests strong nonlinear dependence on the velocity and distance. In close vicinity of metal and dielectric surfaces and velocities ranging from 1 to 10
bohr units the dynamical van der Waals potential proves to be several times lower than in the static case and goes to the static values with increasing the distance and (or) decreasing the velocity.
► Dynamical van der Waals atom–surface interaction can be significantly lower than in the static case. ► The distance/velocity dependence of van der Waals energy is strongly nonlinear. ► The velocity effect diminishes at larger distances and/or smaller velocities.
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