Mathematical modelling of process of salt transfer under filtration and moisture transfer in saturated and non-saturated soil mass with available mobile free surface

Здійснено математичне моделювання процесу солепереносу при сумісній фільтрації підземних вод та вологопереносі в насичено-ненасиченому ґрунтовому середовищі. Розглянуто задачу безнапірної стаціонарної фільтрації сольових розчинів за наявності рухомої вільної поверхні ґрунтових вод, яка задана на межі областей повного та неповного насичення. Вважається, що сольові розчини находять у ґрунтове середовище з поверхні області неповного насичення і вимиваються через дрену (осушувальний режим). На основі побудованої математичної моделі даної крайової задачі проведено дослідження процесу солепереносу до дрени в області повного насичення та процесу вологопереносу з урахуванням солепереносу в області неповного насичення ґрунту; досліджено протікання даних процесів сумісно для обох областей водонасичення. Чисельні розв’язки відповідних крайових задач знайдено методом скінченних різниць із використанням чисельних конформних відображень. На основі програмної реалізації задачі проведено чисельні експерименти та здійснено їх аналіз.The mathematical modelling of the process of salt transfer under joint filtration of ground waters and moisture transfer in saturated-non-saturated soil medium has been carried out. The problem of the free flow stationary filtration of salt solutions under the available mobile free surface of ground waters which is set at the boundary of areas of complete and incomplete saturation has been considered. It is believed that salt solutions enter soil medium from the surface of incomplete saturation and are washed out via drain, i.e. the problem of salt transfer is considered in the case of drainage regime. On the basis of the built mathematical model of this boundary problem the research of the process of salt transfer to the drain in the area of complete saturation and of the process of moisture transfer taking into account salt transfer in the area of incomplete soil saturation has been conducted. The comprehensive study of the process of salt transfer in areas of complete and incomplete saturation is carried out. For this purpose these areas of water saturation are considered as one entity with common unknown boundary which is in the process of problem solution. It makes possible to find the interconnection between investigated processes and to carry out their prediction in the area of saturated-non-saturated soil medium. On the basis of the comprehensive solution of the problem the change of free surface under the influence of processes studied has been established. Numerical solutions of relevant boundary problems are determined by the method of finite differences using numerical conformal mapping. On the basis of programmed implementation of the problem the construction of the conformal mapping in areas of filtration flow, moisture flow and conformal differential network of the area of saturated-non-saturated soil medium has been done; there have been received numerical results and graphical representation of the distribution of the field of piezometric pressure heads, of moisture pressure heads and of concentration of salts in areas of complete and incomplete saturation and also of the distribution of the field of salt solutions concentration in saturated-non-saturated soil mass. A number of numerical experiments has been conducted which gave the possibility to carry out the analysis of results obtained with different initial data of the problem and to research in detail the nature of the action of the process of salt transfer under filtration and of moisture transfer in saturated-non-saturated soil medium

Magnetic field structure in single late-type giants: Beta Ceti in 2010 - 2012

The data were obtained using two spectropolarimeters - Narval at the Bernard Lyot Telescope, Pic du Midi, France, and ESPaDOnS at CFHT, Hawaii. Thirty-eight circularly-polarized spectra have been collected in the period June 2010 - January 2012. The Least Square Deconvolution method was applied for extracting high signal-to-noise ratio line profiles, from which we measure the surface-averaged longitudinal magnetic field Bl. Chromospheric activity indicators CaII K, H_alpha, CaII IR (854.2 nm) and radial velocity were simultaneously measured and their variability was analysed together with the behavior of Bl. The Zeeman Doppler Imaging (ZDI) inversion technique was employed for reconstruction of the large-scale magnetic field and two magnetic maps of Beta Ceti are presented for two periods (June 2010 - December 2010 and June 2011 - January 2012). Bl remains of positive polarity for the whole observational period. The behavior of the line activity indicators is in good agreement with the Bl variations. The two ZDI maps show a mainly axisymmetric and poloidal magnetic topology and a simple surface magnetic field configuration dominated by a dipole. Little evolution is observed between the two maps, in spite of a 1 yr interval between both subsets. We also use state-of-the-art stellar evolution models to constrain the evolutionary status of Beta Ceti. We derive a mass of 3.5 M_sun and propose that this star is already in the central-helium burning phase. Taking into account all our results and the evolutionary status of the star, we suggest that dynamo action alone may not be eficient enough to account for the high magnetic activity of Beta Ceti. As an alternate option, we propose that it may be an Ap star descendant presently undergoing central helium-burning and still exhibiting a remnant of the Ap star magnetic field.Comment: 10 pages; 5 figures; 3 table

Implantation temperature effects on the nanoscale optical pattern fabrication in a-SiC:H films by Ga+ focused ion beams

ArticleProceedings of the IX International Conference on Ion Implantation and Other Applications of Ions and Electrons ION 2012, Kazimierz Dolny, Poland, June 25-28, 2012This work is related to a novel approach of providing some new generation ultrastable (> 50 years), ultrahigh density (> 1 Tbit/sq.in.) data storage for archival applications. We used ion-implantation to write nanoscale data into hydrogenated amorphous silicon carbide (a-SiC:H) films. Wide bandgap a-SiC:H samples, Ga+ focused ion beam implanted, have been prepared. A range of samples has been focused ion beam patterned under different implantation conditions, with emphasis on different substrate temperatures (typically from 0°C temperature to around room temperature). Some of the room temperature implanted samples were further annealed at + 250°C in vacuum. The focused ion beam patterned samples were then analysed using near-field techniques, like atomic force microscopy, to define optimum implantation conditions and the resulting consequences for archival data storage applications. The atomic force microscopy analysis of Ga+ focused ion beam implanted a-Si1 - xCx:H samples at room temperature and at 0°C revealed an increase of both the depth and the width of the individual lines within the focused ion beam written patterns at the lower temperature, as a result of an increased ion beam induced sputtering yield, in good agreement with the previous results for the case of Ga+ broad beam implantation in a-Si1-xCx:H and again suggesting that the best conditions for optical data storage for archival storage applications would be using Ga+ ion implantation in a-SiC:H films with an optimal dose at room temperatures. Similarly, the atomic force microscopy results confirm that no advantage is expected to result from post-implantation annealing treatments.This work has been supported by the European Community as an Integrating Activity “Support of Public and Industrial Research using Ion Beam Technology (SPIRIT)” under EC contract No. 227012. The support of EC funded project BG051PO001/3.3.-05.001 for this publication is gratefully acknowledged. The Marie Curie Fellowship for T. Tsvetkova was also supported by the European Community under the contract PIEF-GA-2009-251845. The help of D. Dimova-Malinovska and O. Angelov with the samples preparation and useful discussions is also gratefully acknowledged

The second Konus-Wind catalog of short gamma-ray bursts

In this catalog, we present the results of a systematic study of 295 short gamma-ray bursts (GRBs) detected by Konus-Wind (KW) from 1994 to 2010. From the temporal and spectral analyses of the sample, we provide the burst durations, the spectral lags, the results of spectral fits with three model functions, the total energy fluences and the peak energy fluxes of the bursts. We discuss evidence found for an additional power-law spectral component and the presence of extended emission in a fraction of the KW short GRBs. Finally, we consider the results obtained in the context of the Type I (merger-origin) / Type II (collapsar-origin) classifications.Comment: Accepted to the Astrophysical Journal Supplement Series (7 Figures, 8 Tables

Development of the technology for obtaining a thick extract from fruits of milk thistle with the stage of ultrasonic influence

This article presents the results of the development of technology for obtaining a thick extract of milk thistle fruits using ultrasonic treatment of plant material and extractant in the soaking stage. Materials and Methods: For the research, crushed fruits of milk thistle from “Biokor” Ltd, Penza, Russia, series 011216 were used, and the shelf life is 2 year