Droplet evaporation in one-component fluids: Dynamic van der Waals theory

In a one-component fluid, we investigate evaporation of a small axysymmetric liquid droplet in the partial wetting condition on a heated wall at $T\sim 0.9 T_c$. In the dynamic van der Waals theory (Phys. Rev. E {\bf 75}, 036304 (2007)), we take into account the latent heat transport from liquid to gas upon evaporation. Along the gas-liquid interface, the temperature is nearly equal to the equilibrium coexisting temperature away from the substrate, but it rises sharply to the wall temperature close to the substrate. On an isothermal substrate, evaporation takes place mostly on a narrow interface region near the contact line in a late stage, which is a characteristic feature in one-component fluids.Comment: 6 pages, 6 figure

Genre-Compositional and Lexical-Semantic Specifics of Advertising SEO-Texts

Genre-compositional and lexical-semantic specifics of the English advertising SEO-texts, which are an integral part of advertising website, are considered. Advertising SEO-text is understood as a genre of advertising discourse in computer-mediated communication produced by taking into account the requirements of search engines and designed to produce a specific pragmatic effect - it urges the recipient to purchase or use the services. It is indicated that advertising SEO-text is not adequately considered in the scientific literature. It is shown that the appearance of this variety of the advertising text is determined by successful operation of the advertising sites in communicative space of the Internet, which in turn requires the use of specific technologies of text generation. The analysis is based on a corpus of advertising SEO-texts, selected by continuous sampling from the main pages of commercial sites in the UK and USA. Basic elements of genre and compositional structure of advertising SEO-text are identified, and their pragmatic and communicative functions are discussed. The analysis of means of implementation of text-forming categories of advertising SEO-text allowed the author to conclude that the category of cohesion is realized mainly by marking the main theme of SEO-text by lexical means of the language, which are in hypero-hyponymic and synonymic semantic relations and are the means of representation of underlying concepts designed to ensure the primary pragmatic function of advertising

Strong spin-orbit induced Gilbert damping and g-shift in iron-platinum nanoparticles

The shape of ferromagnetic resonance spectra of highly dispersed, chemically disordered Fe_{0.2}Pt_{0.8} nanospheres is perfectly described by the solution of the Landau-Lifshitz-Gilbert (LLG) equation excluding effects by crystalline anisotropy and superparamagnetic fluctuations. Upon decreasing temperature, the LLG damping $\alpha(T)$ and a negative g-shift, g(T)-g_0, increase proportional to the particle magnetic moments determined from the Langevin analysis of the magnetization isotherms. These novel features are explained by the scattering of the $q \to 0$ magnon from an electron-hole (e/h) pair mediated by the spin-orbit coupling, while the sd-exchange can be ruled out. The large saturation values, $\alpha(0)=0.76$ and $g(0)/g_0-1=-0.37$, indicate the dominance of an overdamped 1 meV e/h-pair which seems to originate from the discrete levels of the itinerant electrons in the d_p=3 nm nanoparticles.Comment: 8 pages, 4 figures, accepted for publication in Phys. Rev. B (http://prb.aps.org/

Study of fluid behaviour under gravity compensated by a magnetic field

International audienceFluids, and especially cryogenic fluids like Hydrogen H2 and Oxygen O2 , are widely used in space technology for propulsion and cooling. The knowledge of fluid behaviour during the acceleration variation and under reduced gravity is necessary for an efficient management of fluids in space. Such a management also asks fundamental questions about thermo-hydrodynamics and phase change once buoyancy forces are cancelled. For security reasons, it is nearly impossible to use the classical microgravity means to experiment with such cryofluids. However, it is possible to counterbalance gravity by using the paramagnetic (O2) or diamagnetic (H2) properties of fluids. By applying a magnetic field gradient on these materials, a volume force is created that is able to impose to the fluid a varying effective gravity, including microgravity. We have set up a magnetic levitation facility for H2 in which many experiments have been performed. A new facility for O2 is under construction that will enable fast change in the effective gravity by quenching down the magnetic field. The facilities and some particularly representative experimental results are presented

Water recovery from dew

International audienceThe recovery of clean water from dew has remained a longstanding challenge in many places all around the world. It is currently believed that the ancient Greeks succeeded in recovering atmospheric water vapour on a scale large enough to supply water to the city of Theodosia (presently Feodosia, Crimea, Ukraine). Several attempts were made in the early 20th Cent. to build artificial dew-catching constructions which were subsequently abandoned because of their low yield. The idea of dew collection is revised in the light of recent investigations of the basic physical phenomena involved in the formation of dew. A model for calculating condensation rates on real dew condensers is proposed. Some suggestions for the " ideal " condenser are formulated

РИСК-МЕНЕДЖМЕНТ – ИНСТРУМЕНТ ОБЕСПЕЧЕНИЯ БЕЗОПАСНОСТИ ПЕРЕВОЗОК В РОССИИ

Safety of transportation in Russia is subject to a variety of threats. Discussed in the article are characteristics of major threats to transportation security. State transportation policy directions that make it possible to ensure the security of cargo and passenger transportation are shown. A listof activities and innovative risk management tools that provide for improved safety of railway transportation is proposed.Безопасность перевозок в России подвергается целому ряду угроз. Рассматриваются краткие характеристики основных угроз безопасности перевозок. Показаны направления государственной транспортной политики, позволяющей обеспечить безопасностьгрузовых и пассажирских перевозок. Предложен перечень инновационных мероприятий и инструменты риск-менеджмента, обеспечивающие повышение уровня безопасности на железнодорожном транспорте

A linked cluster expansion for the calculation of the semi-inclusive A(e,e'p)X processes using correlated Glauber wave functions

The distorted one-body mixed density matrix, which is the basic nuclear quantity appearing in the definition of the cross section for the semi-inclusive A(e,e'p)X processes, is calculated within a linked-cluster expansion based upon correlated wave functions and the Glauber multiple scattering theory to take into account the final state interaction of the ejected nucleon. The nuclear transparency for 16O and 40Ca is calculated using realistic central and non-central correlations and the important role played by the latter is illustrated.Comment: 18 pages, RevTeX, 3 ps figures. Final version, to appear in Phys. Rev.

On the Synthesis of the Astronomically Elusive 1-Ethynyl-3-Silacyclopropenylidene (c-SiC4H2) Molecule in Circumstellar Envelopes of Carbon-rich Asymptotic Giant Branch Stars and Its Potential Role in the Formation of the Silicon Tetracarbide Chain (SiC4)

Organosilicon molecules such as silicon carbide (SiC), silicon dicarbide (c-SiC2), silicon tricarbide (c-SiC3), and silicon tetracarbide (SiC4) represent basic molecular building blocks connected to the growth of silicon-carbide dust grains in the outflow of circumstellar envelopes of carbon-rich asymptotic giant branch (AGB) stars. Yet, the fundamental mechanisms of the formation of silicon carbides and of the early processes that initiate the coupling of silicon-carbon bonds in circumstellar envelopes have remained obscure. Here, we reveal in a crossed molecular beam experiment contemplated with ab initio electronic calculations that the astronomically elusive 1-ethynyl-3-silacyclopropenylidene molecule (c-SiC4H2, Cs, X1A′) can be synthesized via a single-collision event through the barrierless reaction of the silylidyne radical (SiH) with diacetylene (C4H2). This system represents a benchmark of a previously overlooked class of reactions, in which the silicon-carbon bond coupling can be initiated by a barrierless and overall exoergic reaction between the simplest silicon-bearing radical (silylidyne) and a highly hydrogen-deficient hydrocarbon (diacetylene) in the inner circumstellar envelopes of evolved carbon-rich stars such as IRC+10216. Considering that organosilicon molecules like 1-ethynyl-3-silacyclopropenylidene might be ultimately photolyzed to bare carbon-silicon clusters like the linear silicon tetracarbide (SiC4), hydrogenated silicon-carbon clusters might represent the missing link eventually connecting simple molecular precursors such as silane (SiH4) to the population of silicon-carbide based interstellar grains ejected from carbon-rich AGB stars into the interstellar medium

Quantitative assessment of adherence to treatment in clinical medicine: protocol, procedure, interpretation

We developed and embedded in research and clinical practice of the method of quantitative evaluation of adherence to treatment in clinical medicine. Assessment of adherence is investigated by completion of the questionnaire. Analysis of the answers allows us to quantitatively calculate the indicators of adherence to drug therapy, medical support, modification of lifestyle and integral adherence to treatment. In accordance with the obtained results, an adherence can be «high,» «satisfactory» or «unsatisfactory», serving as a basis for making research or treatment decisions. Dynamic quantitative assessment of adherence allows to assess the current efficacy of interventions and to forecast their trends. The questionnaire is recommended for use in clinical practice when treating patients with chronic diseases, as well as at the stages of organization and execution of clinical studies and clinical trials

IS THERE A NEED TO UNITE TRADITIONAL AND ACADEMIC MEDICINE?

Characteristic features of the eastern tradition of healing and. modern approach to the treatment and. prophylaxis of the diseases are presented in the work. There were discussed the questions concerning the potentialities and. expediency of integration between the given medical systems