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1.
B. A. Benetskii 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(11):1562-1565
Nuclear reactor accidents, accidental radiation injures, the so-called “human factor”, and the distribution of accidental
doses are analyzed. An initial balance equation of dose characteristics is presented. 相似文献
2.
It is shown that the infrared irradiation decreases the content of β-carotene and lycopene carotenoids in human skin. A decrease
in the content of β-carotene and lycopene may indicate that the IR radiation, as well as the UV radiation, is capable of forming
free radicals in human skin. The investigations were performed in vivo using the technique of resonance Raman scattering developed
by us for the noninvasive determination of antioxidant potential in skin. 相似文献
3.
D. V. Karlovets 《Journal of Experimental and Theoretical Physics》2011,113(1):27-45
Polarization radiation generated when a point charge moves uniformly along a straight line in vacuum in the vicinity of media
with a finite permittivity ɛ(ω) = ɛ′ + iɛ″ and sharp boundaries is considered. A method is developed in which polarization radiation is represented as the field of
the current induced in the substance by the field of the moving charge. The solution to the problem of radiation induced when
a charge moves along the axis of a cylindrical vacuum channel in a thin screen with a finite radius and a finite permittivity
is obtained. Depending on the parameters of the problem, this solution describes various types of radiation (Cherenkov, transition,
and diffraction radiation). In particular, when the channel radius tends to zero and the outer radius of the screen tends
to infinity, the expression derived for the emitted energy coincides with the known solution for transition radiation in a
plate. In another particular case of ideal conductivity (ɛ″ → ∞), the relevant formula coincides with the known results for
diffraction radiation from a circular aperture in an infinitely thin screen. The solution is obtained to the problem of radiation
generated when the charge flies near a thin rectangular screen with a finite permittivity. This solution describes the diffraction
and Cherenkov mechanisms of radiation and takes into account possible multiple re-reflections of radiation in the screen.
The solution to the problem of radiation generated when a particles flies near a thin grating consisting of a finite number
of strips having a rectangular cross section and a finite permittivity and separated by vacuum gaps (Smith-Purcell radiation)
is also obtained. In the special case of ideal conductivity, the expression derived for the emitted energy coincides with
the known result in the model of surface currents. 相似文献
4.
M. M. Mogilevsky T. V. Romantsova J. Hanasz T. M. Burinskaya R. Schreiber 《JETP Letters》2007,86(11):709-711
The radiation pattern has been determined on the basis of the comparative analysis of auroral kilometric radiation (AKR) received
in the space-diversity mode by two satellites, Interball-2 and Polar. The radiation propagates in a cone with an opening angle
∼±25° and the axis aligned with the local magnetic field. The results con-firm the theoretical estimates that the source boundaries
play a significant role in the generation of the auroral kilometric radiation and in the formation of the radiation pattern.
Original Russian Text ? M.M. Mogilevsky, T.V. Romantsova, J. Hanasz, T.M. Burinskaya, R. Schreiber, 2007, published in Pis’ma
v Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 11, pp. 819–821. 相似文献
5.
V. A. Nikolaev 《Radiation measurements》1995,25(1-4):337-345
Track methods and devices used for studies conducted after radiation accidents are considered. Solid State Nuclear Track Detectors (SSNTDs) are applied for measurements of contamination in soil, water, biological and other objects of alpha-emitting radionuclides, as well as for estimation of neutron doses by means accident dosimeters. Known radiation accidents (Chernobyl a.o.) and potential emergencies (sunken submarine “Komsomolets”, nuclear reactors) are discussed. Some result of SSNTD application at after-accident period are presented. 相似文献
6.
E. A. Dashko E. V. Kizhaev O. A. Yuminov A. V. Tultaev D. O. Eremenko S. Yu. Platonov O. V. Fotina T. V. Pankratova 《Bulletin of the Russian Academy of Sciences: Physics》2010,74(11):1591-1594
The integral activities of the α-emitting radiopharmaceutical (RP) Astatine-211 are estimated using empirical data on the
pharmacokinetics when RP is introduced into the body. The obtained values are compared to the analogous estimates for RP 131I
in isotonic solution. Linear energy losses are estimated for different organs and tissues of the human body. The linear quadratic
model [1] is used to assess the relative qualitative biological effectiveness of α radiation from 211At. The Medical Internal Radiation Dose Committee (MIRDC) approach is used to analyze equivalent and effectively equivalent
doses for the standard adult body. 相似文献
7.
V. P. Chebotayev V. M. Klementyev Yu. A. Matyugin 《Applied Physics A: Materials Science & Processing》1976,11(2):163-165
The present paper offers a scheme of synthesis and measurement of frequency of 0.63 μm laser radiation based on mixing of
three frequencies of a cascade He-Ne laser generating simultaneously the three lines: 3.39, 2.39, and 1.15 μm. Reported is
an experimental observation of coherent radiation with a wavelength of 0.63 μm arising in mixing of the three frequencies
in a gas. The effective frequency transformation was performed at the nonlinear interaction of three fields resonant with
coupled transitions in neon. Due to the resonance conditions an efficiency of the frequency transformation in a gas proved
to be 8–10 orders higher than that in nonlinear optical crystals. 相似文献
8.
M. H. Saffouri 《Il Nuovo Cimento D》1985,5(2):175-223
Summary A treatment of transition radiation between two dielectric media is presented which is based on the exact expressions for
the fields of the particle in the two media. Expressions for the spectral distribution of the energy emitted forward and for
that emitted backward are derived. The results are in accord with experimental findings for ultra-relativistic particles.
In the asymptotic region the energy spectrum becomes discrete. It is indicated how the treatment can be extended to the case
of a plate and to that of a wave guide, as well as to emission by a monopole. The case of the simultaneous emission of transition
radiation and Čerenkov radiation is considered and the relationship between them is clarified. In particular, it is shown
that, when the particle can emit Čerenkov radiation in the forward medium, it will also emit an interference signal. This
is several orders of magnitude smaller than the usual transition radiation and is concentrated in the forward direction. It
is also found that the Čerenkov wave emitted by the particle in the backward medium will be partially reflected and partially
refracted into the forward medium, after the particle crosses the boundary between the two media. The linear energy density
for the refracted wave is calculated and it is shown that under certain feasible conditions this is amenable to experimental
verification.
This work was done while the author was a summer visitor at Stanford Linear Accelerator Center, Stanford University. It was
supported by the U.S. Department of Energy, contract DE-AC03-76SF00515. 相似文献
9.
The hydrogen migration in metals under the action of ionizing and acoustic radiation is considered. The joint action of ionizing
and acoustic radiation is found to enhance the hydrogen migration in metals (“interference” effect). The hydrogen transport
mechanism is determined by the interaction of ionizing radiation with the hydrogen subsystem of a metal and a vibrodiffusion
effect. 相似文献
10.
S. S. Bulanov R. U. Esiev A. S. Kamrukov N. P. Kozlov M. I. Morozov I. A. Roslyakov 《Technical Physics》2010,55(11):1633-1640
The results of experimental study of explosive radiation sources based on pulsed injection of a cumulative plasma jet into
atmospheric air are considered. The injection process is accompanied with intense vortex formation as well as the formation
of a large-scale toroidal plasma vortex. High-power electromagnetic radiation in the optical range is generated due to shock-wave
processes during deceleration of a plasma jet in air and plasma-chemical processes in the vortex. The temporal structure of
a radiation pulse being generated contains components from the micro- and millisecond range. For a 20-g mass of the explosive
charge, a peak radiation power of 300 kW/sr and an energy yield of 400–600 J/sr integrated over the emission spectrum are
attained. The efficiency of conversion of the chemical energy of the explosive into radiation is 5.0–7.5%. 相似文献
11.
Yu. M. Annenkov 《Russian Physics Journal》2007,50(2):107-119
The mechanisms of the radiation defect formation in alkali halide crystals are studied in an extremely wide range of the absorbed
radiation dose rate (101–1012 Gy/s). It is found that the power dependence of color centers accumulation is described by a curve with a maximum at a dose
rate of about 1010 Gy/s. The electron and proton track parameters for ionic crystals are calculated in the context of the theory of ionization
losses of charged-particle energy. Proceeding from the concept of the charged-particle track overlap, the theoretical relations
are obtained that explain the radiation power effect in all dielectric materials including alkali halide crystals. The suppression
of color center accumulation in these crystals under high-power electron irradiation is due to a more regular topography of
the radiation defect formation.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 10–21, February, 2007. 相似文献
12.
I. E. Vnukov B. N. Kalinin G. A. Naumenko D. V. Padalko A. P. Potylitsyn O. V. Chefonov 《JETP Letters》1998,67(10):802-807
The optical diffraction radiation of ultrarelativistic electrons at the boundary of a conducting medium is observed experimentally.
Backward diffraction radiation, which, like transition radiation, is emitted at the angle of specular reflection from the
target, is detected.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 10, 760–764 (25 May 1998) 相似文献
13.
Enhancement of microwave radiation at wavelength λ ∼ 10 cm in a cavity is simulated using the system of constituent equations
derived earlier. It is shown that a radiation energy density of W ∼ 1000 J/m3 can be attained. Pumping of the medium containing conducting nanoparticles is carried out with a stationary electric field.
The required mass concentration of nanoparticles and pumping field are estimated. A method of obtaining active medium using
a statitionary electric field for enhancement of microwave radiation in a wavelength range of λ ∼ 10 cm is proposed. In this
method, extended conducting nanoparticles should be sputtered. 相似文献
14.
The spatial field distribution is determined for the transition radiation generated by a particle passing through the apex
of a cone along its axis. Expressions for the angular distribution of the radiation intensity are obtained for apex angles
between 0 and π. Characteristics of transition radiation emitted into a “funnel” and a dihedral angle are compared. 相似文献
15.
V. G. Bagrov M. V. Dolzhin K. G. Seravkin V. M. Shakhmatov 《Russian Physics Journal》2006,49(7):681-689
For synchrotron radiation, the partial contribution is defined as the ratio of the power radiated by an individual spectral
harmonic, ν = 1, 2, 3 …, to the total (summed over ν) radiated power. A complete analysis of the dependence of the partial
contribution on ν, polarization of the radiation, and energy of the particle is given.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 3–10, July, 2006. 相似文献
16.
M. M. Mogilevsky I. L. Moiseenko T. V. Romantsova J. Hanasz T. M. Burinskaya D. V. Chugunin 《JETP Letters》2011,93(6):326-329
The enhancement of auroral kilometric radiation near its lowest frequency has been detected in the polar edge of the auroral
zone in the POLRAD experiment with the INTERBALL-2 satellite. The difference between the local electron cyclotron frequency
and the lowest frequency of enhanced radiation is 8–20 kHz, indicating the closeness to the source of auroral kilometric radiation.
According to the detailed analysis of low-frequency auroral kilometric radiation, its amplitude is larger than the “background”
values by a factor of 20–70 and has amplitude modulation with characteristic periods of 40-60 s. The increase in the intensity
at low frequencies is attributed to the intersection of the source region by the satellite and the detection of waveguide
modes in it. 相似文献
17.
S. M. Bezruchko S. M. Kuzmin O. V. Sergeev N. V. Spinko 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2011,5(1):34-42
The applicability of synchrotron radiation to implementation of medical ideas associated with introduction of nonbiological
objects into a human body—implants, drug nanocapsules, and X-ray therapeutic means (metal nanoparticles and nanocrystalline
phosphors and scintillators)—is considered. Synchrotron radiation presents new possibilities of analyzing the surface with
a resolution comparable to the sizes of biological nanostructures involved in interactions such as chemical and biochemical
modification of implant surfaces in vitro; activation of implant surface integration with biological tissue in a tissue culture
(in vitro) and in vivo; biochemical modification of therapeutic nanoparticle surface in vitro; immunocamouflage by host proteins;
attachment of “molecular targets”, i.e., antibodies, to target tissue to provide targeted delivery vehicles; and local activation
of X-ray therapeutic drugs and drug nanocapsules in biological tissues. A functional block diagram of a medical technological
station is given. 相似文献
18.
This paper reports on the first results obtained from the investigation of the effect of IR radiation on the low-temperature
(1.8 ≤ T ≤ 4.2 K) plasticity of solid hydrogen. It has been found that, when the samples are exposed to IR radiation, a drastic increment
ΔɛIR of the elongation per unit length ɛ (which was preliminarily achieved under a continuously applied mechanical stress σ =
const) occurs without an increase in the temperature of the samples. It has been revealed that the effect observed both in
the case of normal hydrogen (n-H2, 75% o-H2) and in the case of parahydrogen (p-H2, ∼0.2% o-H2) only for a sufficiently high power of the IR radiation source has a threshold character. The reverse deformation of solid
hydrogen is observed after the irradiation with a flux of IR photons is completed: the quantity ɛ rapidly decreases to values
provided only by the applied load. The appearance of jumps in the increment of deformation ΔɛIR
i
is interpreted as a consequence of the existence of the fundamental IR absorption band for solid hydrogens. It has been established
that, depending on the time t of exposure of the samples to IR radiation, the change in the quantity ΔɛIR
i
(t) obeys the logarithmic law, which is characteristic of the dislocation creep and observed in the case of unirradiated hydrogen.
It has also been found that, under multiple relatively long-term exposure to IR radiation, the constant α of the logarithmic
creep of n-H2 abruptly decreases, whereas the strength of both the n-H2 and p-H2 samples increases significantly, which indicates their explicit hardening (instead of the expected “superplastic” behavior
due to the exposure to IR irradiation). 相似文献
19.
GU Peijun PEI Wenbing FENG Tinggui & WU Changshu Institute of Applied Physics Computational Mathematics P. O. Box Beijing China 《中国科学G辑(英文版)》2005,48(3):345-360
1 Introduction The laser-target coupling physics is a key topic in indirect-driven inertial confinement fusion (ICF) and X-ray application research[1―3]. When intense laser light irradiates the solid target, the plasmas are produced rapidly on the surface of the target. The laser en-ergy is mainly absorbed by inverse bremsstrahlung absorption, and a coronal region with high-temperature and low-density plasma is formed. Electron thermal conduction proc-ess transfers energy into over-dense re… 相似文献
20.
Two new methods are proposed for determining the polarization of vacuum ultraviolet radiation which permit the determination
of an arbitrary polarization mode for photons with energies of 10–100 eV. The essence of these methods is to create and detect
a nonequilibrium population of the magnetic sublevels of atoms and molecules excited by the original VUV radiation and then
determine the polarization of this radiation based on these measurements in accordance with known formulas.
Zh. Tekh. Fiz. 69, 115–122 (September 1999) 相似文献