Представники роду Pinus L. у ландшафтах дендропарку “Тростянець”

It is presented the short historical data on an introduction, taxonomic structure of the representatives of the genus of Pіnus L., tested in dendropark Trostjanets during the different periods of its existence. The decorative and age condition and the reproductive ability of separate representatives of this genus in conditions of dendropark and their use in park landscapes were investigated.Наведено короткі історичні відомості про інтродукцію і таксономічну структуру представників роду Pinus L., випробуваних у дендропарку “Тростянець” у різні періоди його існування. Досліджено декоративний та віковий стан, репродуктивну спроможність окремих представників роду в умовах дендропарку та використання їх у паркових ландшафтах

Experimental test of the probability density function of true value of Poisson distribution parameter by single observation of number of events

The empirical probability density function for the conditional distribution of the true value of Poisson distribution parameter on one measurement is constructed by computer experiment. The analysis of the obtained distributions confirms that these distributions are gamma-distributions.Comment: presented in the IX International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT'03), KEK, Tsukuba, Japan, December 1-5, 200

Phosphorus-based compounds for EUV multilayer optics materials

We have evaluated the prospects of phosphorus-based compounds in extreme ultraviolet multilayer optics. Boron phosphide (BP) is suggested to be used as a spacer material in reflective multilayer optics operating just above the L-photoabsorption edge of P (λ ≈9.2 nm). Mo, Ag, Ru, Rh, and Pd were considered for applications as reflector materials. Our calculations for multilayer structures with perfect interfaces show that the Pd/BP material combination suggests the highest reflectivity values, exceeding 70% within the 9.2 – 10.0 nm spectral range. We also discuss the potential of fabrication of BP-based multilayer structures for optical applications in the extreme ultraviolet rang

Deposition of refractory metal films with planar plasma ECR source

The condition of the deposition of refractory metal and alloy films such as W, Mo, Ti, Ta, Cr, Ni, Fe₈₀B₂₀ with using ECR plasma source at the different magnitudes of bias voltage on targets and substrates were investigated. It was revealed that the maximal rate of the films growth amounted to 0,052 µm/min for Cr. The thicknesses of the films were obtained of 16-20 µm in the current experiments.Досліджено умови нанесення покритій тугоплавких металів, таких як W, Mo, Ti, Ta, Cr, Ni, а також сплава Fe₈₀B₂₀ з використанням ЕЦР плазмового джерела при різних величинах напруги на мішені та підкладці. Показано, що максимальна швидкість росту товщини покриття складала 0,052 мкм/хв для Cr. В даних експериментах були отримані покриття товщиною порядку 16 - 20 мкм.Исследованы условия нанесения покрытий тугоплавких материалов, таких как W, Mo, Ti, Ta, Cr, Ni, а также сплава Fe₈₀B₂₀ с использованием ЭЦР плазменного источника при различных величинах смещения напряжения на мишени и подложке. Показано, что максимальная скорость роста толщины покрытия составляла 0,052 мкм/мин для Cr. В данных экспериментах были получены покрытия толщиной порядка 16 - 20 мкм

Nanostructured metal-fullerene field emission cathode

One of the important properties of carbon nanostructures is their cold electron emission ability. Carbon nanotubes and other nanostructures are capable of emitting high currents at relatively low electrical fields. They are already used in functional devices such as field emitters. The conventional method of carbon nanostructured cathodes manufacturing is thin film nanocarbon deposition using CVD process on electrically conducting substrate like metal or doped silicon plates. The alternative way of manufacturing of carbon field emission cathodes is based on a special processing of carbon microfibers or composite materials in metal holders. We used the similar approach to produce composite metal-nanocarbon material which may be easily processed and shaped to produce an effective field emission cathode which can be easily fixed an any environment. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2058

Properties of Zirconia Nanoceramics under High-Energy Electrons Irradiation

Formation of radioactive isotopes is investigated under irradiation by relativistic electrons with energy up to 100 MeV. Radioactive isotopes 87,88Y, 88,89,95Zr, 95Nb, 175Hf are registered after irradiation by relativistic electrons with energy 47.2 MeV. The present data are necessary for the choice of a material for a dielectric wakefield accelerator. The greatest danger at operation of accelerators represents 88Y. Formation of radiation defects in nanoceramics is investigated. The various types of radiation defects are found out at an irradiation by relativistic electrons with energy 47 MeV and 86 MeV. In UV VIS spectra the absorption lines of radiation are registered at 402.2 nm and 635 nm, which correspond to the F and F' centers of monocline lattices of zirconia. It is revealed, that krypton atoms are the centers of segregation of point defects. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3562

The study of the negative pion production in neutron-proton collisions at beam momenta below 1.8 GeV/c

A detailed investigation of the reaction np -> pp\pi^{-} has been carried out using the data obtained with the continuous neutron beam produced by charge exchange scattering of protons off a deuterium target. A partial wave event-by-event based maximum likelihood analysis was applied to determine contributions of different partial waves to the pion production process. The combined analysis of the np -> pp\pi^{-} and pp -> pp\pi^{0} data measured in the same energy region allows us to determine the contribution of isoscalar partial waves (I=0) in the momentum range from 1.1 up to 1.8 GeV/c. The decay of isoscalar partial waves into (^1S_0)_{pp}\pi$ channel provides a good tool for a determination of the pp S-wave scalar scattering length in the final state which was found to be a_{pp}=-7.5\pm 0.3 fm.Comment: 6 pages, 6 figure

Ground states of a one-dimensional lattice-gas model with an infinite range nonconvex interaction. A numerical study

We consider a lattice-gas model with an infinite range pairwise noncovex interaction. It might be relevant, for example, for adsorption of alkaline elements on W(112) and Mo(112). We study a competition between the effective dipole-dipole and indirect interactions. The resulting ground state phase diagrams are analysed (numerically) in detail. We have found that for some model parameters the phase diagrams contain a region dominated by several phases only with periods up to nine lattice constants. The remaining phase diagrams reveal a complex structure of usually long periodic phases. We also discuss a possible role of surace states in phase transitions.Comment: 16 pages, 5 Postscript figures; Physical Review B15 (15 August 1996), in pres

LED Monitoring System for the BTeV Lead Tungstate Crystal Calorimeter Prototype

We report on the performance of a monitoring system for a prototype calorimeter for the BTeV experiment that uses Lead Tungstate crystals coupled with photomultiplier tubes. The tests were carried out at the 70 GeV accelerator complex at Protvino, Russia.Comment: 12 pages, 8 figures, LaTeX2e, revised versio

HIgh heat flux plasma testing of ITER divertor materials under ELM relevant conditions in QSPA Kh-50

Performed studies of plasma-surface interaction include measurements of plasma energy deposited to the material surface and determination of tungsten cracking threshold during repetitive ITER ELM-like plasma exposures in QSPA Kh-50 with plasma pulses of energy density up to 2.5 MJ/m2 and duration of 0.25 ms. The energy threshold for tungsten cracking development is found to be ~0,3 MJ/m2. The Ductile-to-Brittle Transition Temperature (DBTT) is experimentally estimated for ITER relevant tungsten grade. Major crack network (cells size up to 1.3 mm) forms only in cases of initial target temperatures below DBTT. Intergranular micro-cracks network (size of cells corresponds to the grain size) appears under heat loads after melting threshold