557 research outputs found
Interior error estimate for periodic homogenization
In a previous article about the homogenization of the classical problem of
diff usion in a bounded domain with su ciently smooth boundary we proved that
the error is of order . Now, for an open set with su ciently
smooth boundary and homogeneous Dirichlet or Neuman limits conditions
we show that in any open set strongly included in the error is of order
. If the open set is of polygonal (n=2) or
polyhedral (n=3) boundary we also give the global and interrior error
estimates
Strain Hardening in Polymer Glasses: Limitations of Network Models
Simulations are used to examine the microscopic origins of strain hardening
in polymer glasses. While traditional entropic network models can be fit to the
total stress, their underlying assumptions are inconsistent with simulation
results. There is a substantial energetic contribution to the stress that rises
rapidly as segments between entanglements are pulled taut. The thermal
component of stress is less sensitive to entanglements, mostly irreversible,
and directly related to the rate of local plastic arrangements. Entangled and
unentangled chains show the same strain hardening when plotted against the
microscopic chain orientation rather than the macroscopic strain.Comment: 4 pages, 3 figure
Particle dynamics inside shocks in Hamilton-Jacobi equations
Characteristics of a Hamilton-Jacobi equation can be seen as action
minimizing trajectories of fluid particles. For nonsmooth "viscosity"
solutions, which give rise to discontinuous velocity fields, this description
is usually pursued only up to the moment when trajectories hit a shock and
cease to minimize the Lagrangian action. In this paper we show that for any
convex Hamiltonian there exists a uniquely defined canonical global nonsmooth
coalescing flow that extends particle trajectories and determines dynamics
inside the shocks. We also provide a variational description of the
corresponding effective velocity field inside shocks, and discuss relation to
the "dissipative anomaly" in the limit of vanishing viscosity.Comment: 15 pages, no figures; to appear in Philos. Trans. R. Soc. series
ΠΡΠΎΠ±Π»Π΅ΠΌΠ° ΠΈΠ½Π΅ΡΡΠΈΠΈ ΠΈ Π°Π½ΡΠΈΠ³ΡΠ°Π²ΠΈΡΠ°ΡΠΈΡ
The main aim of the present paper is to prove the possibility of the phenomenon of antigravity: as is shown by the example of plane curvilinear motion, the material bodies moving by inertia can repel each other. According to the criterion of antigravity obtained, the necessary condition for antigravity is the motion of a body by inertia along such a curvilinear trajectory on which the energy of the body is transferred from the rotational degree of freedom to the translational one. A control parameter is introduced with the change of which the character of particles motion changes: when the control parameter passes through some critical value, the force of attraction between particles is replaced by the repulsive force. Thus, the possibility to control the character of interaction between the particles of a physical system by redistributing the energy of the system between its degrees of freedom is unclosed. It is shown that the extension of the Newtonian scheme of mechanics by taking into consideration a broad class of curvilinear motions by inertia demands the refinement of the standard notion of inertia of the material body. The concept of inertia property should reflect the presence of dialectically opposite components of motion, associated with conservation of two characteristics of body motion β momentum and kinetic energy representing, accordingly, the force and energy measures of motion, mutually supplementing each other. The inertia property of body is that any body opposes to changing both momentum and kinetic energy. The tendency of the body to the conservation of momentum leads to the uniform and rectilinear motion (i.Β e. to translational inertia), and the tendency to kinetic energy conservation β to the curvilinear (accelerated) motion by inertia. Both types of inertial motion have a general feature β they can continue unrestrictedly long. The material bodies, moving along a curvilinear trajectory by inertia, are shown to generate electromagnetic field in environment. This field can be considered as a special physical medium which is created by bodies when they curvilinearly move by inertia and is capable to exert back action upon bodies. The results of the investigation presented in this paper allow one to make a guess that electromagnetism, as well as gravitation, is not a special kind of interaction. Electromagnetism is the interaction of material particles with mass that are in such states of curvilinear motion by inertia in which energy is transferred from some degrees of freedom to others.ΠΠ»Π°Π²Π½ΡΠΉ ΡΠ΅Π·ΡΠ»ΡΡΠ°Ρ Π½Π°ΡΡΠΎΡΡΠ΅ΠΉ ΡΠ°Π±ΠΎΡΡ ΡΠΎΡΡΠΎΠΈΡ Π² Π΄ΠΎΠΊΠ°Π·Π°ΡΠ΅Π»ΡΡΡΠ²Π΅ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΠΈ ΡΠ²Π»Π΅Π½ΠΈΡ Π°Π½ΡΠΈΠ³ΡΠ°Π²ΠΈΡΠ°ΡΠΈΠΈ: Π½Π° ΠΏΡΠΈΠΌΠ΅ΡΠ΅ ΠΏΠ»ΠΎΡΠΊΠΎΠ³ΠΎ ΠΊΡΠΈΠ²ΠΎΠ»ΠΈΠ½Π΅ΠΉΠ½ΠΎΠ³ΠΎ Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ ΠΏΠΎ ΠΈΠ½Π΅ΡΡΠΈΠΈ ΠΏΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΡΠ½ΡΠ΅ ΡΠ΅Π»Π°, ΠΎΠ±Π»Π°Π΄Π°ΡΡΠΈΠ΅ ΠΌΠ°ΡΡΠΎΠΉ, ΠΌΠΎΠ³ΡΡ ΠΎΡΡΠ°Π»ΠΊΠΈΠ²Π°ΡΡΡΡ Π΄ΡΡΠ³ ΠΎΡ Π΄ΡΡΠ³Π°. Π£ΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ ΠΊΡΠΈΡΠ΅ΡΠΈΠΉ Π°Π½ΡΠΈΠ³ΡΠ°Π²ΠΈΡΠ°ΡΠΈΠΈ, ΡΠΎΠ³Π»Π°ΡΠ½ΠΎ ΠΊΠΎΡΠΎΡΠΎΠΌΡ Π½Π΅ΠΎΠ±Ρ
ΠΎΠ΄ΠΈΠΌΡΠΌ ΡΡΠ»ΠΎΠ²ΠΈΠ΅ΠΌ Π°Π½ΡΠΈΠ³ΡΠ°Π²ΠΈΡΠ°ΡΠΈΠΈ ΡΠ²Π»ΡΠ΅ΡΡΡ ΠΏΠ΅ΡΠ΅ΠΌΠ΅ΡΠ΅Π½ΠΈΠ΅ ΡΠ΅Π»Π° ΠΏΠΎ ΠΈΠ½Π΅ΡΡΠΈΠΈ ΠΏΠΎ ΡΠ°ΠΊΠΎΠΌΡ ΠΊΡΠΈΠ²ΠΎΠ»ΠΈΠ½Π΅ΠΉΠ½ΠΎΠΌΡ ΠΏΡΡΠΈ, Π½Π° ΠΊΠΎΡΠΎΡΠΎΠΌ ΠΏΡΠΎΠΈΡΡ
ΠΎΠ΄ΠΈΡ ΠΏΠ΅ΡΠ΅ΠΊΠ°ΡΠΊΠ° ΡΠ½Π΅ΡΠ³ΠΈΠΈ ΡΠ΅Π»Π° ΠΈΠ· Π²ΡΠ°ΡΠ°ΡΠ΅Π»ΡΠ½ΠΎΠΉ ΡΡΠ΅ΠΏΠ΅Π½ΠΈ ΡΠ²ΠΎΠ±ΠΎΠ΄Ρ Π² ΠΏΠΎΡΡΡΠΏΠ°ΡΠ΅Π»ΡΠ½ΡΡ. ΠΠ²Π΅Π΄Π΅Π½ ΡΠΏΡΠ°Π²Π»ΡΡΡΠΈΠΉ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡ, Ρ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ΠΌ Π²Π΅Π»ΠΈΡΠΈΠ½Ρ ΠΊΠΎΡΠΎΡΠΎΠ³ΠΎ ΠΈΠ·ΠΌΠ΅Π½ΡΠ΅ΡΡΡ Ρ
Π°ΡΠ°ΠΊΡΠ΅Ρ Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ ΡΠ΅Π»: ΠΏΡΠΈ ΠΏΠ΅ΡΠ΅Ρ
ΠΎΠ΄Π΅ ΡΠΏΡΠ°Π²Π»ΡΡΡΠ΅Π³ΠΎ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠ° ΡΠ΅ΡΠ΅Π· Π½Π΅ΠΊΠΎΡΠΎΡΠΎΠ΅ ΠΊΡΠΈΡΠΈΡΠ΅ΡΠΊΠΎΠ΅ Π·Π½Π°ΡΠ΅Π½ΠΈΠ΅ ΡΠΈΠ»Π° ΠΏΡΠΈΡΡΠΆΠ΅Π½ΠΈΡ ΠΌΠ΅ΠΆΠ΄Ρ ΡΠ΅Π»Π°ΠΌΠΈ ΡΠΌΠ΅Π½ΡΠ΅ΡΡΡ ΡΠΈΠ»ΠΎΠΉ ΠΎΡΡΠ°Π»ΠΊΠΈΠ²Π°Π½ΠΈΡ. ΠΡΠΊΡΡΠ²Π°Π΅ΡΡΡ, ΡΠ°ΠΊΠΈΠΌ ΠΎΠ±ΡΠ°Π·ΠΎΠΌ, Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΡ ΡΠΏΡΠ°Π²Π»Π΅Π½ΠΈΡ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΎΠΌ Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΡ ΠΌΠ΅ΠΆΠ΄Ρ ΡΠ°ΡΡΠΈΡΠ°ΠΌΠΈ ΡΠΈΠ·ΠΈΡΠ΅ΡΠΊΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΡ ΠΏΡΡΠ΅ΠΌ ΠΏΠ΅ΡΠ΅ΡΠ°ΡΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ ΡΠ½Π΅ΡΠ³ΠΈΠΈ ΡΠΈΡΡΠ΅ΠΌΡ ΠΌΠ΅ΠΆΠ΄Ρ Π΅Π΅ ΡΡΠ΅ΠΏΠ΅Π½ΡΠΌΠΈ ΡΠ²ΠΎΠ±ΠΎΠ΄Ρ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΡΠ°ΡΡΠΈΡΠ΅Π½ΠΈΠ΅ Π½ΡΡΡΠΎΠ½ΠΎΠ²ΡΠΊΠΎΠΉ ΡΡ
Π΅ΠΌΡ ΠΌΠ΅Ρ
Π°Π½ΠΈΠΊΠΈ ΠΏΡΡΠ΅ΠΌ Π²ΠΊΠ»ΡΡΠ΅Π½ΠΈΡ Π² ΡΠ°ΡΡΠΌΠΎΡΡΠ΅Π½ΠΈΠ΅ ΠΎΠ±ΡΠΈΡΠ½ΠΎΠ³ΠΎ ΠΊΠ»Π°ΡΡΠ° ΠΊΡΠΈΠ²ΠΎΠ»ΠΈΠ½Π΅ΠΉΠ½ΡΡ
Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΠΉ ΠΏΠΎ ΠΈΠ½Π΅ΡΡΠΈΠΈ ΡΡΠ΅Π±ΡΠ΅Ρ ΡΡΠΎΡΠ½Π΅Π½ΠΈΡ ΠΎΠ±ΡΠ΅ΠΏΡΠΈΠ½ΡΡΡΡ
ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½ΠΈΠΉ ΠΎ ΡΠ²ΠΎΠΉΡΡΠ²Π΅ ΠΈΠ½Π΅ΡΡΠΈΠΈ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΡΠ½ΠΎΠ³ΠΎ ΡΠ΅Π»Π°. ΠΠΎΠ½ΡΡΠΈΠ΅ Β«ΡΠ²ΠΎΠΉΡΡΠ²ΠΎ ΠΈΠ½Π΅ΡΡΠΈΠΈΒ» Π΄ΠΎΠ»ΠΆΠ½ΠΎ ΠΎΡΡΠ°ΠΆΠ°ΡΡ Π½Π°Π»ΠΈΡΠΈΠ΅ Π΄ΠΈΠ°Π»Π΅ΠΊΡΠΈΡΠ΅ΡΠΊΠΈ ΠΏΡΠΎΡΠΈΠ²ΠΎΠΏΠΎΠ»ΠΎΠΆΠ½ΡΡ
ΡΠΎΡΡΠ°Π²Π»ΡΡΡΠΈΡ
Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ, ΡΠ²ΡΠ·Π°Π½Π½ΡΡ
Ρ ΡΠΎΡ
ΡΠ°Π½Π΅Π½ΠΈΠ΅ΠΌ Π΄Π²ΡΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ ΡΠ΅Π»Π° β ΠΈΠΌΠΏΡΠ»ΡΡΠ° ΠΈ ΠΊΠΈΠ½Π΅ΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΡΠ½Π΅ΡΠ³ΠΈΠΈ, ΠΊΠΎΡΠΎΡΡΠ΅ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»ΡΡΡ ΡΠΎΠ±ΠΎΠΉ, ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²Π΅Π½Π½ΠΎ, ΡΠΈΠ»ΠΎΠ²ΡΡ ΠΈ ΡΠ½Π΅ΡΠ³Π΅ΡΠΈΡΠ΅ΡΠΊΡΡ ΠΌΠ΅ΡΡ Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ, Π²Π·Π°ΠΈΠΌΠ½ΠΎ Π΄ΠΎΠΏΠΎΠ»Π½ΡΡΡΠΈΠ΅ Π΄ΡΡΠ³ Π΄ΡΡΠ³Π°. Π‘Π²ΠΎΠΉΡΡΠ²ΠΎ ΠΈΠ½Π΅ΡΡΠΈΠΈ ΡΠ΅Π»Π° Π·Π°ΠΊΠ»ΡΡΠ°Π΅ΡΡΡ Π² ΡΠΎΠΌ, ΡΡΠΎ Π²ΡΡΠΊΠΎΠ΅ ΡΠ΅Π»ΠΎ ΡΠΎΠΏΡΠΎΡΠΈΠ²Π»ΡΠ΅ΡΡΡ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ ΠΊΠ°ΠΊ ΠΈΠΌΠΏΡΠ»ΡΡΠ°, ΡΠ°ΠΊ ΠΈ ΠΊΠΈΠ½Π΅ΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΡΠ½Π΅ΡΠ³ΠΈΠΈ. Π‘ΡΡΠ΅ΠΌΠ»Π΅Π½ΠΈΠ΅ ΡΠ΅Π»Π° ΠΊ ΡΠΎΡ
ΡΠ°Π½Π΅Π½ΠΈΡ ΠΈΠΌΠΏΡΠ»ΡΡΠ° ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡ ΠΊ ΡΠ°Π²Π½ΠΎΠΌΠ΅ΡΠ½ΠΎΠΌΡ ΠΈ ΠΏΡΡΠΌΠΎΠ»ΠΈΠ½Π΅ΠΉΠ½ΠΎΠΌΡ Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ (Ρ.Β Π΅. ΠΊ ΠΏΠΎΡΡΡΠΏΠ°ΡΠ΅Π»ΡΠ½ΠΎΠΉ ΠΈΠ½Π΅ΡΡΠΈΠΈ), Π° ΡΡΡΠ΅ΠΌΠ»Π΅Π½ΠΈΠ΅ ΠΊ ΡΠΎΡ
ΡΠ°Π½Π΅Π½ΠΈΡ ΠΊΠΈΠ½Π΅ΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΡΠ½Π΅ΡΠ³ΠΈΠΈ β ΠΊ ΠΊΡΠΈΠ²ΠΎΠ»ΠΈΠ½Π΅ΠΉΠ½ΠΎΠΌΡ (ΡΡΠΊΠΎΡΠ΅Π½Π½ΠΎΠΌΡ) Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ ΠΏΠΎ ΠΈΠ½Π΅ΡΡΠΈΠΈ. ΠΠ±Π° ΡΠΈΠΏΠ° Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ ΠΏΠΎ ΠΈΠ½Π΅ΡΡΠΈΠΈ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΠ·ΡΡΡΡΡ ΡΠ΅ΠΌ, ΡΡΠΎ ΠΎΠ½ΠΈ ΠΌΠΎΠ³ΡΡ ΠΏΡΠΎΠ΄ΠΎΠ»ΠΆΠ°ΡΡΡΡ ΡΠΊΠΎΠ»Ρ ΡΠ³ΠΎΠ΄Π½ΠΎ Π΄ΠΎΠ»Π³ΠΎ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΡΠ½ΡΠ΅ ΡΠ°ΡΡΠΈΡΡ, Π΄Π²ΠΈΠΆΡΡΠΈΠ΅ΡΡ ΠΏΠΎ ΠΊΡΠΈΠ²ΠΎΠ»ΠΈΠ½Π΅ΠΉΠ½ΠΎΠΌΡ ΠΏΡΡΠΈ ΠΏΠΎ ΠΈΠ½Π΅ΡΡΠΈΠΈ, Π³Π΅Π½Π΅ΡΠΈΡΡΡΡ ΡΠ»Π΅ΠΊΡΡΠΎΠΌΠ°Π³Π½ΠΈΡΠ½ΠΎΠ΅ ΠΏΠΎΠ»Π΅ Π² ΠΎΠΊΡΡΠΆΠ°ΡΡΠ΅ΠΌ ΠΏΡΠΎΡΡΡΠ°Π½ΡΡΠ²Π΅. ΠΡΠΎ ΠΏΠΎΠ»Π΅ ΠΌΠΎΠΆΠ½ΠΎ ΡΠ°ΡΡΠΌΠ°ΡΡΠΈΠ²Π°ΡΡ ΠΊΠ°ΠΊ ΠΎΡΠΎΠ±ΡΡ ΡΠΈΠ·ΠΈΡΠ΅ΡΠΊΡΡ ΡΡΠ΅Π΄Ρ, ΠΊΠΎΡΠΎΡΠ°Ρ ΠΏΠΎΡΠΎΠΆΠ΄Π°Π΅ΡΡΡ ΡΠ΅Π»Π°ΠΌΠΈ ΠΏΡΠΈ ΠΈΡ
ΠΊΡΠΈΠ²ΠΎΠ»ΠΈΠ½Π΅ΠΉΠ½ΠΎΠΌ Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΠΈ ΠΏΠΎ ΠΈΠ½Π΅ΡΡΠΈΠΈ ΠΈ ΡΠΏΠΎΡΠΎΠ±Π½Π° ΠΎΠΊΠ°Π·ΡΠ²Π°ΡΡ ΠΎΠ±ΡΠ°ΡΠ½ΠΎΠ΅ Π²ΠΎΠ·Π΄Π΅ΠΉΡΡΠ²ΠΈΠ΅ Π½Π° ΡΠ΅Π»Π°. ΠΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½Π½ΡΠ΅ Π² ΡΠ°Π±ΠΎΡΠ΅ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΡ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΡΡ ΠΏΡΠ΅Π΄ΠΏΠΎΠ»ΠΎΠΆΠΈΡΡ, ΡΡΠΎ ΡΠ»Π΅ΠΊΡΡΠΎΠΌΠ°Π³Π½Π΅ΡΠΈΠ·ΠΌ, ΠΊΠ°ΠΊ ΠΈ Π³ΡΠ°Π²ΠΈΡΠ°ΡΠΈΡ, Π½Π΅ ΡΠ²Π»ΡΠ΅ΡΡΡ ΠΎΡΠΎΠ±ΡΠΌ Π²ΠΈΠ΄ΠΎΠΌ Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΡ. ΠΠ»Π΅ΠΊΡΡΠΎΠΌΠ°Π³Π½Π΅ΡΠΈΠ·ΠΌ β ΡΡΠΎ Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΠ΅ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΡΠ½ΡΡ
ΡΠ°ΡΡΠΈΡ, ΠΎΠ±Π»Π°Π΄Π°ΡΡΠΈΡ
ΠΌΠ°ΡΡΠΎΠΉ ΠΈ Π½Π°Ρ
ΠΎΠ΄ΡΡΠΈΡ
ΡΡ Π² ΠΎΡΠΎΠ±ΡΡ
ΡΠΎΡΡΠΎΡΠ½ΠΈΡΡ
ΠΊΡΠΈΠ²ΠΎΠ»ΠΈΠ½Π΅ΠΉΠ½ΠΎΠ³ΠΎ Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ ΠΏΠΎ ΠΈΠ½Π΅ΡΡΠΈΠΈ, Π² ΠΊΠΎΡΠΎΡΡΡ
ΠΏΡΠΎΠΈΡΡ
ΠΎΠ΄ΠΈΡ ΠΏΠ΅ΡΠ΅ΠΊΠ°ΡΠΊΠ° ΡΠ½Π΅ΡΠ³ΠΈΠΈ ΠΈΠ· ΠΎΠ΄Π½ΠΈΡ
ΡΡΠ΅ΠΏΠ΅Π½Π΅ΠΉ ΡΠ²ΠΎΠ±ΠΎΠ΄Ρ Π² Π΄ΡΡΠ³ΠΈΠ΅
Homogenization of Maxwell's equations in periodic composites
We consider the problem of homogenizing the Maxwell equations for periodic
composites. The analysis is based on Bloch-Floquet theory. We calculate
explicitly the reflection coefficient for a half-space, and derive and
implement a computationally-efficient continued-fraction expansion for the
effective permittivity. Our results are illustrated by numerical computations
for the case of two-dimensional systems. The homogenization theory of this
paper is designed to predict various physically-measurable quantities rather
than to simply approximate certain coefficients in a PDE.Comment: Significantly expanded compared to v1. Accepted to Phys.Rev.E. Some
color figures in this preprint may be easier to read because here we utilize
solid color lines, which are indistinguishable in black-and-white printin
Muon pair creation from positronium in a circularly polarized laser field
We study elementary particle reactions that result from the interaction of an
atomic system with a very intense laser wave of circular polarization. As a
specific example, we calculate the rate for the laser-driven reaction , where the electron and positron originate from a positronium
atom or, alternatively, from a nonrelativistic plasma. We distinguish
accordingly between the coherent and incoherent channels of the process. Apart
from numerical calculations, we derive by analytical means compact formulas for
the corresponding reaction rates. The rate for the coherent channel in a laser
field of circular polarization is shown to be damped because of the destructive
interference of the partial waves that constitute the positronium ground-state
wave packet. Conditions for the observation of the process via the dominant
incoherent channel in a circularly polarized field are pointed out
Somatoform disorders in the family doctor's practice.
Somatoform disorders β psychoΒgenic diseases are characterized by pathological physical symptoms that resemble somatic illness. Thus, any organic manifestations, which can be attributed to known diseases are not detected, but there are non-specific functional impairments. Somatoform disorders include somatization disorder, undifferentiated somatoform disorder, hypochoΒnΒdriacal disorder, somatoform dysfunction of the autonomic nervous system and stable somatoform pain disorder. The first part of the article reviewes features of the clinical manifestations of somatization disorder and undifferentiated somatoform disorder. Role of non-benzodiazepine tranquilizers (ADAPTOL) and metabolic drugs (VASONAT) in the treatment of patients with somatoform disorders is discussed. In review article data of neurologists and cardiologists on the effectiveness of anxiolytic drug ADAPTOL and metabolic drug VASONAT in different clinical groups of patients (coronary artery disease, chronic ischemia of the brain), which can significantly improve quality of life, increase exercise tolerance, improve cognitive function and correct mental and emotional disorders are presented
NUMERICAL STUDY OF OIL SPILL IN THE PATOS LAGOON ESTUARY REGION
The consumption pattern of the world population is based on petroleum derivatives, which despite contributing to the improvement of the quality of life, has negative aspects, mainly in the environmental scope. The number of oil spills in water slide has increased significantly in recent years. Considering the complexity of the marine environment, the present work aims to apply a identification system of the dynamics and dispersion of oil, using the numerical modeling in the region of Franceses Bridge, near to Patos Lagoon-RS, Brazil. The study of hypothetical events of oil leakage in the region is of fundamental importance, since the Riograndense Petroleum Refinery is located inside of the Patos Lagoon estuary. A data structure of atmospheric and oceanic circulation was organized and inserted in the coupling between the hydrodynamic module Telemac-3D and the ECOS oil model, during the period between 2010 and 2013. The coupling of these models provided satisfactory results, requiring a level of computational effort favorable to obtaining of results capable of giving technical and scientific support to studies such as those of environmental impacts and contingency plans
- β¦