336 research outputs found
Landau damping in thin films irradiated by a strong laser field
The rate of linear collisionless damping (Landau damping) in a classical
electron gas confined to a heated ionized thin film is calculated. The general
expression for the imaginary part of the dielectric tensor in terms of the
parameters of the single-particle self-consistent electron potential is
obtained. For the case of a deep rectangular well, it is explicitly calculated
as a function of the electron temperature in the two limiting cases of specular
and diffuse reflection of the electrons from the boundary of the
self-consistent potential. For realistic experimental parameters, the
contribution of Landau damping to the heating of the electron subsystem is
estimated. It is shown that for films with a thickness below about 100 nm and
for moderate laser intensities it may be comparable with or even dominate over
electron-ion collisions and inner ionization.Comment: 15 pages, 2 figure
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The effect of nonlinearity in CO2 heating rates on the attribution of stratospheric ozone and temperature changes
An analysis of the attribution of past and future changes in stratospheric ozone and temperature to anthropogenic forcings is presented. The analysis is an extension of the study of Shepherd and Jonsson (2008) who analyzed chemistry-climate simulations from the Canadian Middle Atmosphere Model (CMAM) and attributed both past and future changes to changes in the external forcings, i.e. the abundances of ozone-depleting substances (ODS) and well-mixed greenhouse gases. The current study is based on a new CMAM dataset and includes two important changes. First, we account for the nonlinear radiative response to changes in CO2. It is shown that over centennial time scales the radiative response in the upper stratosphere to CO2 changes is significantly nonlinear and that failure to account for this effect leads to a significant error in the attribution. To our knowledge this nonlinearity has not been considered before in attribution analysis, including multiple linear regression studies. For the regression analysis presented here the nonlinearity was taken into account by using CO2 heating rate, rather than CO2 abundance, as the explanatory variable. This approach yields considerable corrections to the results of the previous study and can be recommended to other researchers. Second, an error in the way the CO2 forcing changes are implemented in the CMAM was corrected, which significantly affects the results for the recent past. As the radiation scheme, based on Fomichev et al. (1998), is used in several other models we provide some description of the problem and how it was fixed
Investigation converter circuit "voltage-current" for power calibrator
The paper presents alternative circuits for voltage-current converters to be used in the calibrator of fictitious power. The experimental studies have revealed a number of problems related to the stability of the system in deep feedback and zero level stabilization of the amplifier. The circuit solutions given in the article allow elimination of these problems and improve the accuracy of calibrator current calibration. For example, correction/corrective circuits are used to ensure the stability of the converter at deep depths of the feedback, and operational amplifier based circuit solution and compensation condition are proposed to reduce the additional phase shift. To improve the accuracy of the calibration current values specified by the calibrator we propose to connect the feedback circuit to the measuring current transformer. However, further improvement of the accuracy class of the power calibrator is impossible without modern electronic components
Comparative analysis of taxation for special economic zones in Russia and APEC economies
The article is devoted to the analysis of taxation of special economic zones, since special economic zones have become a center of attention in Russia over the latest decades. As objects for the study, the authors selected special economic zones in Russia and the countries participating in the Forum of the Asia-Pacific Economic Cooperation (APEC Forum).
In the article the authors consider history, modern conditions and prospects for the development of special economic zones. The peculiarities of taxations on profits, organizations' property, transport, land, insurance contributions into the non-budget funds, as well as value-added taxation for the residents of the RF special economic zones are analyzed with regard to their types.
The authors assess tax privileges and preferences for some taxes in the special economic zones in Russia and APEC member-countries are evaluated. The main problems of the taxation of the RF special economic zones are articulated together with the possible ways to solve them regarding the experience of APEC economies.
As a result of the study, the authors concluded that to increase the effectiveness of special economic zones in Russia, it is necessary to expand the list of tax benefits to introduce a progressive scale of tax incentives, following the example of APEC countries and to improve legislation in the regulation of special economic zones.peer-reviewe
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Response of the middle atmosphere to CO2 doubling: results from the Canadian Middle Atmosphere Model
The Canadian Middle Atmosphere Model (CMAM) has been used to examine the middle atmosphere response to CO2 doubling. The radiative-photochemical response induced by doubling CO2 alone and the response produced by changes in prescribed SSTs are found to be approximately additive, with the former effect dominating throughout the middle atmosphere. The paper discusses the overall response, with emphasis on the effects of SST changes, which allow a tropospheric response to the CO2 forcing. The overall response is a cooling of the middle atmosphere accompanied by significant increases in the ozone and water vapor abundances. The ozone radiative feedback occurs through both an increase in solar heating and a decrease in infrared cooling, with the latter accounting for up to 15% of the total effect. Changes in global mean water vapor cooling are negligible above ~30 hPa. Near the polar summer mesopause, the temperature response is weak and not statistically significant. The main effects of SST changes are a warmer troposphere, a warmer and higher tropopause, cell-like structures of heating and cooling at low and middlelatitudes in the middle atmosphere, warming in the summer mesosphere, water vapor increase throughout the domain, and O3 decrease in the lower tropical stratosphere. No noticeable change in upwardpropagating planetary wave activity in the extratropical winterβspring stratosphere and no significant temperature response in the polar winterβspring stratosphere have been detected. Increased upwelling in the tropical stratosphere has been found to be linked to changed wave driving at low latitudes
Three-body correlations in direct reactions: Example of Be populated in reaction
The Be continuum states were populated in the charge-exchange reaction
H(Li,Be) collecting very high statistics data ( events) on the three-body ++ correlations. The
Be excitation energy region below MeV is considered, where the
data are dominated by contributions from the and states. It is
demonstrated how the high-statistics few-body correlation data can be used to
extract detailed information on the reaction mechanism. Such a derivation is
based on the fact that highly spin-aligned states are typically populated in
the direct reactions.Comment: submitted to Physical Review
Technological support of sports and educational process of pupils on the basis of use Slavic historical and cultural values and traditions
Π ΡΠ°Π±ΠΎΡΠ΅ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½ΠΎ ΡΠΎΠ΄Π΅ΡΠΆΠ°Π½ΠΈΠ΅ Π½Π°ΡΡΠ½ΠΎ-ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΠ΅Π»ΡΡΠΊΠΎΠ³ΠΎ ΠΏΡΠΎΠ΅ΠΊΡΠ°, Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½Π½ΠΎΠ³ΠΎ Π½Π° ΡΠ°Π·ΡΠ°Π±ΠΎΡΠΊΡ ΠΏΠ΅Π΄Π°Π³ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΎΠΉ ΡΠ΅Ρ
Π½ΠΎΠ»ΠΎΠ³ΠΈΠΈ ΡΠΈΠ·ΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π²ΠΎΡΠΏΠΈΡΠ°Π½ΠΈΡ ΡΡΠ°ΡΠΈΡ
ΡΡ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΡ ΡΠ»Π°Π²ΡΠ½ΡΠΊΠΈΡ
ΠΈΡΡΠΎΡΠΈΠΊΠΎ-ΠΊΡΠ»ΡΡΡΡΠ½ΡΡ
ΡΡΠ°Π΄ΠΈΡΠΈΠΉ. ΠΠΊΡΡΠ°Π»ΡΠ½ΠΎΡΡΡ ΠΏΠΎΠ΄ΠΎΠ±Π½ΠΎΠ³ΠΎ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΠΎΠ±ΡΡΠ»ΠΎΠ²Π»Π΅Π½Π° Π½Π΅ΠΎΠ±Ρ
ΠΎΠ΄ΠΈΠΌΠΎΡΡΡΡ Π³Π°ΡΠΌΠΎΠ½ΠΈΠ·Π°ΡΠΈΠΈ ΠΈ ΠΈΠ½ΡΠ΅Π³ΡΠ°ΡΠΈΠΈ Π΄ΡΡ
ΠΎΠ²Π½ΠΎ-Π½ΡΠ°Π²ΡΡΠ²Π΅Π½Π½ΠΎΠ³ΠΎ ΠΈ ΡΠΈΠ·ΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΡΠ°Π·Π²ΠΈΡΠΈΡ ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
ΡΠΊΠΎΠ»ΡΠ½ΠΈΠΊΠΎΠ².In work the contents of the research project directed on development of pedagogical technology of physical training of pupils on the basis of use of Slavic historical and cultural traditions are submitted. Relevance of similar research is caused by need of harmonization and integration of spiritual and moral and physical development of modern school student
10He low-lying states structure uncovered by correlations
The 0+ ground state of the 10He nucleus produced in the 3H(8He,p)10He
reaction was found at about MeV (\Gamma ~ 2 MeV) above the
three-body 8He+n+n breakup threshold. Angular correlations observed for 10He
decay products show prominent interference patterns allowing to draw
conclusions about the structure of low-energy excited states. We interpret the
observed correlations as a coherent superposition of the broad 1- state having
a maximum at energy 4-6 MeV and the 2+ state above 6 MeV, setting both on top
of the 0+ state "tail". This anomalous level ordering indicates that the
breakdown of the N=8 shell known in 12Be thus extends also to the 10He system.Comment: 5 pages, 5 figure
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