ISSN 0869-6632 (Print)
ISSN 2542-1905 (Online)


Новое в прикладной физике

The effect of various electrodes on the character of the course of chemical oscillating reactions Briggs–Rauscher

Purpose of the present study is to determine the sensitivity of chemical self-oscillating reactions to various types of electrodes: silver chloride electrode, carbon electrode, platinum electrode. Methods.

О нелинейной теории двухрезонаторного клистрона с пространством дрейфа в виде среды с комплексной диэлектрической проницаемостью

Цель настоящей работы. Построить приближенную нелинейную теорию клистрона-усилителя, в котором между входным и выходным резонатором вместо пространства дрейфа располагается среда с комплексной проводимостью или с метаматериалами с отрицательной диэлектрической проницаемостью. В рамках построенной теории рассчитать выходные характеристики (коэффициент усиления, выходную мощность и КПД) описываемого прибора и сравнить результаты с классическим двухрезонаторным клистроном. Методы.

ВЛИЯНИЕ МАТЕРИАЛОВ РАЗЛИЧНЫХ ЭЛЕКТРОДОВ НА ХАРАКТЕР ПРОТЕКАНИЯ ХИМИЧЕСКОЙ АВТОКОЛЕБАТЕЛЬНОЙ РЕАКЦИИ БРИГГСА-РАУШЕРА

Исследованы параметры автоколебательной реакции Бриггса- Раушера при использовании различных электродов: ионоселективного электрода (йодид) и электрода сравнения (хлоридсеребряного электрода, угольного электрода, платинового электрода). Показано, что использование хлоридсеребряного электрода может вносить изменения в параметры автоколебательного процесса реакции Бриггса-Раушера, в связи с высокой чувствительностью реакции к примеси, связанной с диффузией электролита из хлоридсеребряного электрода.

Micromagnetic modeling of nonlinear interaction of lateral magnetostatic modes in cross-shaped structures based on waveguides from iron yttrium garnet films

Topic. In this work, parametric processes in the system of predominantly dipole magnetostatic waves (MSW) in the cross-shaped structure from two orthogonal waveguides of iron yttrium garnet film magnetized by the in-plane field H = 460 Oe and having microstrip transducers at its ends are considered. One of the antennas at the end of the transversely

Zones of stable single-mode generation in overmoded gyrotrons

During numerical simulations of the model of gyrotron with ?xed ?eld-structure, zones of stable single-mode generation of the work mode are analyzed on the plane of parameters «magnetic ?eld – beam current». It is shown that area and sizes of the zones are strongly dependent on the spectral density of eigen-frequencies of the resonator and on number of considered parasit modes.

Electrodynamical characteristicsof periodic ferromagnetic structures

The periodic structure consisting of a shallow grooves on a surface of a ferromagnetic ?lm was investigated. The electrodynamical characteristics of propagation of the surface magnetostatic wave in this structure were obtained. The 2D model of the periodical Yttrium Iron Garnet structure was numerically studied by the algorithm based on the Finite Element method. The spatial distribution of the electric and magnetic ?eld components in di?erent points of dispersion characteristics was studied in detail.

Methods of output power increasing in orotron with double- row periodic structure in the short-wavelength part of millimeter-wave range

The peculiarities of the orotron double-row electrodynamical system and methods of output power increase were investigated. For the ?rst time in the experimental model of orotron with electrodynamical system consisting of double-row plain periodic structure (DRPS) and sphere-cylindrical focusing mirror the possibility of using wide electron beam in order to output power increase in 140...300 GHz frequency range is demonstrated.

Development in spbspu of field emitters for electron devices operating at technical vacuum conditions

The methods of ?eld emitter durability growth while operating in technical vacuum conditions are developed in SPbSPU and are describing in this paper. Two possibilities to secure durable emitter operation are considered: using the special protective fullerene coatings and arrangement of new type of emitter where the ?elds of spots on the contacts of the materials with greatly di?erent work function provide the ?eld emission.

The carbon nanotubes grown on molybdenum substratesby cvd-method using thin metal films of iron and water solutions of ferriferous substances as catalysts

The synthesis of carbon nanotubes is carried out on the surface of molybdenum substrates by CVD-method using thin-?lm iron and water solutions of ferritin and iron acetate as catalysts sources. It is found that the temperature of process technology in the synthesis of carbon nanotubes on molybdenum substrates must be above 900 ?C. At this point, only non-uniform ?lms of carbon nanotubes on the surface of molybdenum substrates were obtained.

Study of discrete electron-wave interaction in the passband and stopband of slow-wave systems

This article contains analysis of properties discrete electron-wave interaction in resonance slow-wave system (SWS). Equations of interaction are written in matrix form. Eigenvalues of transfer matrix with electron beam de?ne spread constant of four electron waves. Features of electron waves in SWS with «smooth» energy stream and in SWS with «winding» ?ow are examined. Simulation is performed and ampli?cation of multisection TWT with passband and stopband sections of SWS is found. Field distribution along stopband section is found.

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