Spin excitations in a Ferromagnetic Nanorice-type Cluster

In the paper, dipole-exchange spin excitations in a composite nanorice-type nanoparticle (prolate rotation ellipsoid) are investigated theoretically. A nanorice with a non-magnetic core and a shell composed of an uniaxial ferromagnet is considered. Spin dynamics in the above-described nanosystem is described using the linearized Landau-Lifshitz equation (in the magnetostatic approximation) with the addends that consider the magnetic dipole-dipole interaction, the exchange interaction and the anisotropy effects. An equation for the magnetic potential of the above-described spin excitations is obtained. For the case of a thin shell, a solution for the above-mentioned equation in the form of a combination of the generalized spheroidal functions is proposed. For the above-described case, a dispersion relation for such spin excitations is also found

Підсумки інтродукції деревних екзотів родини Rosaceae Juss. у ботанічному саду Прикарпатського університету ім. В. Стефаника

Introduction of 15 exotic trees of Rosaceae family in the central part of Precarpathia have been investigated. It was established that mainly species from Atlantic-North-American floristic area and some Iran-Turanian one are perspective for green plantations.В результаті проведених досліджень з інтродукції 15 видів родини Rosaceae Juss. на Прикарпатті встановлено, що перспективними для вирощування у зелених насадженнях є види переважно Атлантично-Північноамериканської флористичної області та 1 вид Ірано-Туранської

Super-transport of energy in ultra-short processes: implications to heat transfer, fluid dynamics and quantum mechanics

Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.The paradox of instantaneous propagation of energy is intrinsic to the classical models of energy transport. This paradox becomes well-pronounced during ultra-short processes. To remove the paradox, phase-lagged models of energy transport have been proposed. The analysis of the solutions to the phaselagged energy equations suggests that when the characteristic time of the process is much less than the lag time, the wave mode of transport becomes the main mechanism of energy transfer. In ultra-short heat transfer processes, the wave transport is manifested by an apparent increase (three-four orders of magnitude) of the thermal conductivity of the transporting medium. In viscous fluid flow, in addition, an apparent decrease of viscosity occurs, so that the liquid behaves as superfluid even at high temperatures. It has been demonstrated that the lag time is inversely proportional to the temperature. Thus the life span of the supertransport phenomena should significantly increase at low temperatures, which is consistent with observing superfluids at lower temperatures for long periods of time. From the quantum physics standpoint, the energy transporting waves can be viewed as narrow wave packets, whose wave functions describe the superfluid state of the liquid. This may provide an alternative explanation of the phenomenon of superfluidity: the Bose-Einstein condensation may not be needed for superfluidity to occur. From the phase-lagged model of energy transport, it follows that the Schrödinger equation is but a zero-time-lag approximation. Hence, the phase-lagged Schrödinger equation must be used to describe ultra-short quantum interactions. It is suggested that the finiteness of Planck’s constant and the finiteness of the speed of energy propagation are not independent. This circumstance may shed some light on the understanding of processes that took place in the beginning of our Universe.vk201

EH-undulative system for “effective cooling” of electron beams

The system for forming charged particles beams with small energy spread is proposed and studied. It is constructed on the basis of the Undulative Induction Accelerator (EH-accelerator). The obtained results of numerical modeling show that the proposed system allows to reduce the beam energy spread more than ~40 times. The mechanism of energy “equalization” of electrons during the accelerating beam is investigated. This mechanism is called the "effective cooling"

Undulative induction electron accelerator for the waste and natural water purification systems

The project analysis of Undulative Induction Accelerator (EH-accelerator) for the waste and natural water purification systems is accomplished. It is shown that the use of the four-channel design of induction block and the standard set of auxiliary equipment (developed earlier for the Linear Induction Accelerators - LINACs) allow to construct commercially promising purification systems. A quality analysis of the accelerator is done and the optimal parameters are chosen taking into account the specific sphere of its usage

Undulative induction formers of picosecond electron bunches

The basic physical mechanism and the design idea of a new type of Undulative Induction Formers (UNIFs or EH-formers) of especially short intensive electron bunches are proposed and studied. The characteristic feature of the proposed EH-former is the employing of nonstationary crossed linearly polarized electrical and magnetic undulative fields (EH-fields). Namely, the EH-former turns out to be "opened" for an electron beam only during a very short (picosecond) time interval. A possibility to form rather intensive picosecond electron bunches is shown. Including, the picosecond bunches with a number of electrons in each bunch ~ 10⁸÷10¹⁰

Mathematical Based Calculation of Drug Penetration Depth in Solid Tumors

Cancer is a class of diseases characterized by out-of-control cells' growth which affect cells and make them damaged. Many treatment options for cancer exist. Chemotherapy as an important treatment option is the use of drugs to treat cancer. The anticancer drug travels to the tumor and then diffuses in it through capillaries. The diffusion of drugs in the solid tumor is limited by penetration depth which is different in case of different drugs and cancers. The computation of this depth is important as it helps physicians to investigate about treatment of infected tissue. Although many efforts have been made on studying and measuring drug penetration depth, less works have been done on computing this length from a mathematical point of view. In this paper, first we propose phase lagging model for diffusion of drug in the tumor. Then, using this model on one side and considering the classic diffusion on the other side, we compute the drug penetration depth in the solid tumor. This computed value of drug penetration depth is corroborated by comparison with the values measured by experiments

The quasi-cooling effect of relativistic charged particles beams

A possibility of realization of a new, of principle, physical phenomenon is shown. This is the phenomenon of energy equalization of charged particle beams in the time their acceleration in the crossed undulative electric and magnetic fields (EH-fields). The phenomenon predicted is referred to as the quasi-cooling effect. Main properties and features of the effect are studied. In particular, it is shown that it would be experimentally observed for the existing today level of acceleration technologies.Описано новий фізичний ефект - ефект вирівнювання енергій заряджених частинок пучка під час їх прискорення в схрещених електричному та магнітному ондуляторних полях (EH-полях). Даний ефект трактується як ефект ефективного охолодження. Вивчено загальні властивості та основні характеристики даного ефекту. Зокрема показано, що дане явище може бути експериментально реалізовано на існуючому рівні прискорювальних технологій.Описан новый физический эффект - эффект выравнивания энергий заряженных частиц пучка при их ускорении в скрещенных электрическом и магнитном ондуляторных полях (EH-полях). Данный эффект трактуется, как эффект эффективного охлаждения. Изучены основные особенности и характеристики данного эффекта. В том числе показано, что данный эффект может быть экспериментально реализован на существующем уровне ускорительных технологий

Analysis of the silicon solar cells efficiency. Type of doping and level optimization

The theoretical analysis of photovoltaic conversion efficiency of highly effective silicon solar cells (SC) has been performed for n-type and p-type bases. Considered here is the case when the Shockley–Read–Hall recombination in the silicon bulk is determined by the deep level of Fe. It has shown that, due to asymmetry of recombination parameters inherent to this level, the photovoltaic conversion efficiency is increased in SC with the n-type base and decreased in SC with the p-type base with the increase in doping. Two approximations for the band-to-band Auger recombination lifetime dependence on the base doping level are considered when performing the analysis. The experimental results are presented for the key characteristics of SC based on a-Si:H–n-Si heterojunctions with intrinsic thin layer (HIT). A comparison between the experimental and calculated values of the HIT cell characteristics has been made. The surface recombination velocity and series resistance are determined from it with a complete coincidence of the experimental and calculated SC parameters’ values. Apart from the key characteristics of SC, surface recombination rate and series resistance were determined from the results of this comparison, in full agreement with the experimental findings

Electron and vibration structure of fluorine-containing polyamide film under high energetic electron irradiation

Influence of high energetic electron irradiation (Еᵢ = 1.8 МеV) on the electron and vibrational properties of fluorine containing polyamide films was studied. Nature of electron transitions and vibration bands in Raman and IR-absorption spectra in the initial state of the film was determined by quantum-chemical calculations. Results of optical absorption, Raman scattering and IR-absorption showed that irradiation of the film with dose of 1 MGy does not lead to significant changes of electron and vibrational structure. Increase of the dose to 3 MGy influences the intensity of vibration bands in Raman and IR-absorption spectra. Films that were transparent in the initial state became yellow-colored and fragile after the irradiation.Приведено дослідження впливу опромінення плівок фторвмісного поліаміду високоенергетичними електронами (Еᵢ = 1,8 МеВ) на його електронну та коливну структуру. За допомогою квантово-хімічних розрахунків встановлено природу електронних переходів та смуг КРС, а також ІЧ-поглинання у вихідному стані. Результати оптичного та ІЧ-поглинаннь, раманівського розсіяння світла показують, що дані плівки при дозі 1 МГр зберігають свою електронну та коливну структуру. Збільшення дози до 3 МГр призводить до зміни інтенсивностей коливних мод у спектрах раманівського розсіяння та ІЧ-поглинання. При даній дозі плівки втрачають прозорість, набуваючи жовтого кольору, і стають крихкими.Приведены исследования влияния облучения пленок фторсодержащего полиамида высокоэнергетическими электронами (Еᵢ = 1,8 МэВ) на его электронную и колебательную структуру. С помощью квантово-химических расчетов установлена природа электронных переходов и полос КРС, а также ИК-поглощения в исходном состоянии. Результаты оптического и ИК-поглощения, рамановского рассеяния света показывают, что данные пленки при дозе 1 МГр сохраняют свою электронную и колебательную структуру. Увеличение дозы до 3 МГр приводит к изменению интенсивностей колеблющихся мод в спектрах рамановского рассеяния и ИК-поглощения. При данной дозе пленки теряют прозрачность, приобретая желтый цвет, и становятся хрупкими