107 research outputs found
Организация работы докторантуры как третьего уровня высшего образования в европейских университетах в свете Болонского процесса
The doctoral training in European university education system is considered. Structure of educational process and system of maintenance of quality of doctoral studies of the European countries is reviewed.В статье анализируется организация докторантуры в системе университетского образования в странах Европы. Внимание уделяется структуре учебного процесса и системе обеспечения качества докторской подготовки в европейских странах
Numerical study of the centre region acceleration for the RIC-30 cyclotron
The RIC-30 cyclotron was designed for acceleration of protons up to 30 MeV [1]. Since 1994 it has been used
for production of radionuclides on internal target installed at a radius of 580 mm, where the beam energy equals
22 MeV. Final radius of acceleration is 655 mm. At present, in the long-time irradiation mode the beam current on
target is 190...200 µA [2]. The main objective of the work is to attain a higher beam current due to optimizing configuring of components forming the central ion-optical system of the cyclotron.RIC-30 циклотрон був розроблений для прискорення протонів до 30 МеВ. З 1994 p. він використовувався
для виробництва радіонуклідів на внутрішній мішені, встановленої на радіусі 580 мм, де енергія пучка
дорівнювала 22 МеВ. Кінцевий радіус прискорення дорівнює 655 мм. В даний час при тривалому режимі
опромінення струм пучка на мішені – 190...200 мкА. Основною метою роботи є одержання більш високого
струму пучка внаслідок оптимізації конфігурації компонент, що формують центральну іон-оптичну систему
циклотрона.RIC-30 циклотрон был разработан для ускорения протонов до 30 МэВ. С 1994 г. он использовался для
производства радионуклидов на внутренней мишени, установленной на радиусе 580 мм, где энергия пучка
равнялась 22 МэВ. Конечный радиус ускорения равен 655 мм. В настоящее время при длительном режиме
облучения ток пучка на мишени – 190...200 мкА. Основной целью работы является получение более высокого тока пучка вследствие оптимизации конфигурации компонент, формирующих центральную ион-оптическую систему циклотрона
Design and simulation of a SOI based mems differential accelerometer
In this paper, the design and analysis of a differential MEMS capacitive accelerometer is presented. The device is designed to be compatible for SOI based fabrication process. The outstanding mechanical and electrical properties of silicon on insulator (SOI) wafers make it popular for high-performance MEMS sensors such as accelerometers. The operating range of the designed device is 0-10g with its sense axis in the in-plane direction. The movable comb fingers attached to the proof mass form capacitors with the fixed electrode fingers. The movable and fixed fingers are spaced with unequal gaps to form the differential capacitive sensing configuration. The base capacitance of this configuration is about 0.77pF and the sensitivity in response to acceleration input is about 0.776 fF/g. The resonance frequency of the structure in the sensing mode is found to be 7.138 kHz.The work was partially funded by the Russian Federation Ministry of Education and Science
Design, simulation and fabrication process of a SOI based 2-DOF vibratory gyroscope
This paper reports the design, simulation and fabrication process for a 2-DOF decoupled vibratory gyroscope. The structure is deliberately designed to have decoupled drive and sense mode oscillation to prevent unstable operation due to mechanical coupling, resulting in low zero rate out-put drift. At the same time, the closer the drive and sense resonances are, the higher is the angular rate resolution of the gyroscope. This can be achieved by using symmetric suspensions, but it results in reduced bandwidth. The proposed design has been configured to achieve about 150 Hz bandwidth, while ensuring decoupled operation of the drive and sense modes. Fem analysis has been carried out in CoventorWare® MEMS DESIGN software and simulation results show that the drive resonance occurs at 21.48 kHz and sense resonance at 21.63 kHz. The structure is designed for 15 µm this device layer. Fabrication of the design is proposed using DRIE and sacrificial release etching on SOI wafer. DRIE etching with high aspect ratio has been successfully carried out as desired and the results have been presented
Quantum coherence in a degenerate two-level atomic ensemble: for a transition
For a transition driven by a linearly polarized
light and probed by a circularly light, quantum coherence effects are
investigated. Due to the coherence between the drive Rabi frequency and Zeeman
splitting, electromagnetically induced transparency, electromagnetically
induced absorption, and the transition from positive to negative dispersion are
obtained, as well as the populations coherently oscillating in a wide spectral
region. At the zero pump-probe detuning, the subluminal and superluminal light
propagation is predicted. Finally, coherent population trapping states are not
highly sensitive to the refraction and absorption in such ensemble.Comment: 9 pages, 6 figure
Cefpodoxime proxetil – new opportunities in antibacterial therapy of respiratory infections
The purpose of the expert council was to determine the place of cefpodoxime in the ABT algorithms for upper and lower respiratory tract infections and to form a consensus position on its use in clinical practice. Based on the available data, the possibility of including cefpodoxime in national guidelines for the treatment of rhinosinusitis, acute tonsillopharyngitis, community-acquired pneumonia (CAP), as well as infectious exacerbations of chronic bronchitis (CB) and chronic obstructive pulmonary disease (COPD) is being considered
Fragmentation and Multifragmentation of 10.6A GeV Gold Nuclei
We present the results of a study performed on the interactions of 10.6A GeV
gold nuclei in nuclear emulsions. In a minimum bias sample of 1311 interac-
tions, 5260 helium nuclei and 2622 heavy fragments were observed as Au projec-
tile fragments. The experimental data are analyzed with particular emphasis of
target separation interactions in emulsions and study of criticalexponents.
Multiplicity distributions of the fast-moving projectile fragments are inves-
tigated. Charged fragment moments, conditional moments as well as two and three
-body asymmetries of the fast moving projectile particles are determined in
terms of the total charge remaining bound in the multiply charged projectile
fragments. Some differences in the average yields of helium nuclei and heavier
fragments are observed, which may be attributed to a target effect. However,
two and three-body asymmetries and conditional moments indicate that the
breakup mechanism of the projectile seems to be independent of target mass. We
looked for evidence of critical point observable in finite nuclei by study the
resulting charged fragments distributions. We have obtained the values for the
critical exponents gamma, beta and tau and compare our results with those at
lower energy experiment (1.0A GeV data). The values suggest that a phase
transition like behavior, is observed.Comment: latex, revtex, 28 pages, 12 figures, 3tables, submitted to Europysics
Journal
New insights into the Weichselian environment and climate of the East Siberian Arctic, derived from fossil insects, plants, and mammals
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