Наукові роботи. Фізичний факультет
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Документ Temperature dependence of surface energy of solids(STC “Institute for Single Crystals”, 1994) Gladkikh, N.T.; Dukarov, S.V.; Larin, V.I.The surface energy of a number of solid metals (In, Sn, Bi, Pb and Au) is determined in the temperature range (0.6-1)Ts from the size dependence of melting temperature for small particles of these metals. A nonlinear decreasing of surface energy is established in the region of premelting temperatures that is attributed to the increase of the vacancy concentration. The obtained data are compared with available ones for massive samples. . . . . . . . . . . . . . . . . . Определена поверхностная энергия металлов In, Sn, Bi, Pb и Au в твердой фазе в интервале температур (0.6-1)Ts по данным зависимости температуры плавления малых частиц этих металлов от их размера. Установлено нелинейное уменьшение поверхностной энергии я области яредллавильных температур, которое объясняется увеличением концентрации вакансий. Проведено сравнение полученных результатов с имеющимися данными для массивных образцов. . . . . . . . . . . . . . . . . . . . Визначено поверхневу енергію металів In, Sn, Bi, Pb та Au в твердій фазі в інтервалі температур (0.6-1)Ts за даними залежності температури плавлення малих частинок цих металів від їх розміру. Встановлено нелінійне зменшення поверхневої енергії в області передплавильних температур, яке пояснюється збільшенням концентрації вакансій. Проведено порівняння одержаних результатів з наявними даними для масивних зразків.Документ Electronographic investigation of the temperature effect on the phase formation in thin double-layer Ni/GaAs films(1998) Gladkikh, N.T.; Grebennik, I.P.; Dukarov, S.V.The results of an electronographic investigation of the Ni—GaAs double-layer films phase composition depending on temperature at condensation of Ni at GaAs are presented. The structure and number of the phases being formed have been shown to depend both on ther-mal conditions at interaction of the Ni and GaAs layers and on the Ni to GaAs layer mass ratio: mNi//mGaAs = (0.5; 1.2).Документ Effect of condensation conditions on phase formation in thin two-layer Ni/GaAs films(STC “Institute for Single Crystals”, 1998) Grebennik, I.P.; Gladkikh, N.T.; Dukarov, S.V.The temperature and structure state of substrate (NaCl poly- and single crystals) are shown to influence the structure of phases formed as a result of interaction between Ni and GaAs layers. In films on polycrystal substrates, polycrystal phases with structures similar to the γ-, γ'-, NiAs, Ni3Ga4 phases in Ni-Ga and Ni-As systems are formed besides the amorphous one. Single crystal substrate exerts an orienting influence resulting in the energetically favourable growth of the hexagonal phase of the triple system with parameters aγ''= aγ', cγ'' = 2cγ'. . . . . . . . . . . . . . . . . . . Показано, что температура и структурное состояние подложки (поли- и монокристаллов NaCl) оказывает влияние на структуру фаз, образующихся при взаимодействии слоев Ni и GaAs. На поликристаллических подложках в пленках, наряду с аморфной, образуются поликристаллические фазы, структура которых подобна фазам γ-, γ'-, NiAs, Ni3Ga4, в системах Ni-Ga, Ni-As. Монокристаллическая подложка оказывает ориентирующее действе и приводит к энергетически более выгодному росту гексагональной фазы тройной системы с параметрами aγ''= aγ', cγ'' = 2cγ'.Документ Lead wetting of thin nickel films deposited onto GaAs(STC “Institute for Single Crystals”, 1996) Gladkikh, N.T.; Dukarov, S.V.The wetting of nickel films deposited onto (111) face of GaAs single crystals with island lead condensates has been studied. The wetting angle, θ, is found to depend on the Ni film thickness, t, and to change within the limits defined by wetting of pure GaAs (t = 0, θ ≈ 120°) and compact-state nickel wetting (t > 20 nm, θ ≈ 20°). The change of θ is explained as due to the surface heterogeneity arising as a result of chemical interaction between nickel film and gallium arsenide and of nickel dissolution in the liquid lead. - - - - - - - - - - - - - - - - Изучено смачивание островковыми конденсатами свинца пленок никеля, нанесенных на монокристалл арсенида галлия (грань (111)). Установлено, что краевой угол θ зависит от толщины t пленки Ni и изменяется в крайних пределах, соответствующих смачиванию чистого GaAs (t = 0, θ ≈ 120°) и смачиванию никеля в компактном состоянии (t > 20 nm, θ ≈ 20°). Изменение θ объясняется гетерогенностью смачиваемой поверхности, возникающей в результате химического взаимодействия пленки никеля с арсенидом галлия и растворения никеля в жидком свинце.Документ Size and temperature effects in wetting in island films(1994) Gladkikh, N.T.; Dukarov, S.V.; Gabusu, P.A.This paper is devoted to studies of wetting in metal island films on different substrates in the broad ranges of temperature (from 0.6 to 1.5 of the melting temperature), island size (from 3 nm to 10 mkm) and thickness of films serving as substrates (from 0 to 100 nm).Документ Supercooling during metal crystallization under conditions close to weightlessness using island vacuum condensates(1996) Gladkikh, N.T.; Dukarov, S.V.; Sukhov, V.N.Island vacuum condensates the properties of which are determined by surface phenomena rather than the force of gravity actually permit to eliminate the effect of alien impurities and own oxides on supercooling ΔT during crystallization. Their application also allows to measure the dependence of ΔT on the contact angle θ between a droplet of a liquid metal and the substrate on which condensation and subsequent crystallization occur. For the metals under study (Au, In, Bi, Pb, Sn, Fe, Co, Ni) the supercooling ΔT is shown to increase with the angle θ growing. With wetting angles θ > 130 ° the supercooling ΔT does not depend anymore on the substrate material and for θ → 180° it approaches a value somewhat below 0.4 Ts, where Ts is the bulk melting temperature.Документ Effect of an electric field on coalescence in gallium island films(1990) Chizhik, S.P.; Dukarov, S.V.; Gladkikh, N.T.; Grigoryeva, L.K.It was found that the external longitudinal electric field stimulates coalescence in gallium island films with different particle sizes on a poorly conducting carbon substrate, which can be considered as a manifestation of the particle mutual-charging effect. - - - - - - - - - - - - - - - Установлено, что внешнее продольное электрическое поле стимулирует процесс коалесценции в островковых пленках галлия с различным размером частиц на слабопроводящей углеродной подложке, что может рассматриваться как проявление эффекта взаимного заряжения частиц.Документ Size Effect upon Solidification of Small Bismuth Particles(1998) Gladkikh, N.T.; Dukarov, S.V.; Kryshal, A.P.; Larin, V.I.Electron microscopy was used to study the dependence of the crystallization temperature on the particle size upon solidification of small bismuth particles produced by vapor deposition on substrates of amorphous carbon. The crystallization temperature for particles 2–100 nm in diameter was found to decrease with decreasing diameter of the particles; and for particles 2–3 nm in diameter, supercooling was equal to zero. The results were analyzed within the classic theory of solidification; it was shown that, for the smallest particles, a size effect consisting in the change of the character of the liquid-crystal phase transition is observed.Документ Size effects in wetting for highly dispersed systems(Gordon and Breach Science Publishers S.A., 1989) Chizhik, S.P.; Gladkikh, N.T.; Larin, V.I.; Grigoryeva, L.K.; Dukarov, S.V.; Stepanova, S.V.Wetting in systems with different dispersities of the solid and liquid phases and with different types of interfacial interaction was investigated. Studied were liq-uid metal-amorphous carbon and liquid metal-solid metal film-ionic crystal sys-tems in which the drop size and the thickness of film-substrates varied in the range 3x10^5–2x10^2 nm, respectively. It was found that for systems of the metal-amorphous carbon type a reduction in particle size and in thickness of carbon films brings about a size effect during wetting as a consequence of a decrease in the surface energy of the corresponding dispersed phase. For metal-metal-ionic crystal systems, a size effect during wetting is also observed but it is mainly caused by a changed nature of the interfacial interaction in the dispersed phases. Some parameters derived from the experimental data determine the dependence of the surface energy of small particles on their size.Документ Methods of determination of wetting in highly dispersed systems(Gordon and Breach Science Publishers S.A., 1987) Gladkikh, N.T.; Chizhik, S.P.; Larin, V.I.; Grigoryeva, L.K.; Dukarov, S.V.Procedures are described for studying the wetting of solid substrates by island vacuum condensates. The proposed methods are based on the application of optical and electron microscopy and may be used to find the angles of contact over a wide range of particle sizes (3-10^5 nm).