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1.
Life Sci Space Res (Amst) ; 39: 106-118, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945083

RESUMO

The dosimeter Liulin-MO for measuring the radiation environment onboard the ExoMars Trace Gas Orbiter (TGO) is a module of the Fine Resolution Epithermal Neutron Detector (FREND). Here we present results from measurements of the charged particle fluxes, dose rates and estimation of dose equivalent rates at ExoMars TGO Mars science orbit, provided by Liulin-MO from May 2018 to June 2022. The period of measurements covers the declining and minimum phases of the solar activity in 24th solar cycle and the rising phase of the 25th cycle. Compared are the radiation values of the galactic cosmic rays (GCR) obtained during the different phases of the solar activity. The highest values of the dose rate and flux from GCR are registered from March to August 2020. At the minimum of 24th and transition to 25th solar cycle the dose rate from GCR is 15.9 ± 1.6 µGy h-1, particle flux is 3.3 ± 0.17 cm-2s-1, dose equivalent rate is 72.3 ± 14.4 µSv h-1. Since September 2020 the dose rate and flux of GCR decrease. Particular attention is drawn to the observation of the solar energetic particle (SEP) events in July, September and October 2021, February and March 2022 as well as their effects on the radiation environment on TGO during the corresponding periods. The SEP event during15-19 February 2022 is the most powerful event observed in our data. The SEP dose during this event is 13.8 ± 1.4 mGy (in Si), the SEP dose equivalent is 21.9 ± 4.4 mSv. SEP events recorded in Mars orbit are related to coronal mass ejections (CME) observed by SOHO and STEREO A coronagraphs. Compared are the time profiles of the count rates measured by Liulin-MO, the neutron detectors of FREND and neutron detectors of the High Energy Neutron Detector (HEND) aboard Mars Odyssey during 15-19 February 2022 event. The data obtained is important for the knowledge of the radiation environment around Mars, regarding future manned and robotic flights to the planet. The data for SEP events in Mars orbit during July 2021-March 2022 contribute to the details on the solar activity at a time when Mars is on the opposite side of the Sun from Earth.


Assuntos
Radiação Cósmica , Monitoramento de Radiação , Voo Espacial , Atividade Solar , Órbita , Monitoramento de Radiação/métodos
2.
Opt Express ; 16(25): 20266-71, 2008 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-19065165

RESUMO

We study experimentally nonlinear tunable magnetic metamaterials operating at microwave frequencies. We fabricate the nonlinear metamaterial composed of double split-ring resonators where a varactor diode is introduced into each resonator so that the magnetic resonance can be tuned dynamically by varying the input power. We demonstrate that at higher powers the transmission of the metamaterial becomes power-dependent and, as a result, such metamaterial can demonstrate various nonlinear properties. In particular, we study experimentally the power-dependent shift of the transmission band and demonstrate nonlinearity-induced enhancement (or suppression) of wave transmission.


Assuntos
Magnetismo , Manufaturas , Teste de Materiais , Micro-Ondas , Modelos Teóricos , Simulação por Computador , Dinâmica não Linear , Espalhamento de Radiação
3.
Opt Express ; 15(18): 11714-22, 2007 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-19547532

RESUMO

We study experimentally propagation of electromagnetic waves through a slab of uniaxial magnetic metamaterial. We observe a range of novel phenomena including partial focusing and splitting into multiple transmitted beams.We demonstrate that while some of these experimentally observed effects can be described within the approximation of an effective medium, a deeper understanding of the experimental results requires a rigorous study of internal eigenmodes of the lattice of resonators.

4.
Care Manag J ; 7(2): 92-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17214242

RESUMO

In Russia, charity started developing into a public welfare system after the transition to Christianity. Peter the Great played an important role in establishing the social welfare system. According to his decree from June 8, 1701, "charity houses for beggars, sick people, and elderly" started their existence. During the reign of Catherine II, also known as Catherine the Great, decrees about public welfare were approved at regional levels.


Assuntos
Pessoas com Deficiência , Assistência de Longa Duração/organização & administração , Seguridade Social , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Assistência de Longa Duração/economia , Masculino , Federação Russa
5.
Phys Rev Lett ; 94(20): 203902, 2005 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-16090248

RESUMO

The theory of the inverse Doppler effect recently observed in magnetic nonlinear transmission lines is developed. We explain the crucial role of the backward spatial harmonic in the occurrence of an inverse Doppler effect and draw analogies of the magnetic nonlinear transmission line to the backward wave oscillator.

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