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Several solar events with different types of negative microwave bursts have been studied using data from different spectral ranges. The total radio flux data obtained at the Ussuriysk Observatory, the Nobeyama Observatory, the US Air Force Radio Solar Telescope Network (RSTN), and the spectropolarimeter of the Institute of Solar–Terrestrial Physics, Siberian Branch of the Russian Academy of Sciences (ISTP SB RAS) were used. The images were analyzed using data from the SDO/AIA space observatory in the 304 Å channel and the Nobeyama radio heliograph at a frequency of 17 GHz. It was shown that the “isolated” depressions of radio emission were caused by the absorption of radiation from radio sources and/or vast regions of the quiet Sun by low-temperature material of a large eruptive filament in the absence of flares. This confirmed the conclusions of the previous studies. It was revealed that the cause of negative bursts of the “pre-burst depression” type was the screening of a near-limb radio source by the material of coronal jets. In the case of a weak flare accompanying the jet, the negative burst could also be of the “isolated” type. A case of a previously unreported occurrence of a deeper depression of radio emission at high frequencies as compared to low frequencies was considered. It was shown that negative bursts are not as rare phenomena as previously thought.

In the article the substantiation of the organization of a new specially protected natural area of the Rostovregion «Topilinskaya Gully» is given. Topilinskaya gully is forested, located on the Donetsk ridge on the northern borderof the Nizhnekundryuchensky sandу massif. A brief description of the flora and vegetation of the gully is given. The mainassociations, typical, relict and protected forest and psammophytic species are listed. The flora of the gully includes 178species of higher vascular plants from 51 families and 139 genera.

The article gives a brief description of seed plants flora of the State Wildlife area «Gornenskiy» (GPZ«Gornenskiy»). The flora of Wildlife area includes 507 species from 70 families and 278 genera. Species of steppeecology are dominated in the flora, and the sinatropization index is 19.1 %. On the territory of the Wildlife area there arecoenopopulations of 28 species, included in the Red Lists of the Rostov Region and the Russian Federation, as well as 57species included in the IUCN Red List. Floristic representativeness of GPZ «Gornenskiy» in relation to flora of Rostovregion is 25.4 %.

The vortex tube operation is considered. The effect of separation of the peripheral and axial layers of gas at full temperature due to the exchange of work and heat between them is studied. The mechanism of kinetic energy transfer from the axis of the periphery is determined. The effect of viscosity forces and the gradient of angular velocities on the energy exchange in a vortex tube is verified. There is experimentally found dependence on the thermophysical properties of energy gas, a gas pressure value at the inlet of the vortex tube and exit valve and diaphragm geometric parameters of the main elements of the vortex tube. There is conducted research to identify the nature of the vortex effect — of the fibers of the gas temperature. The question of the development of the theory of real phenomena (Rank effect) is considered. It is shown that the main work of the authors of this article can be regarded as the theory of the Rank effect

As a result of our research, we propose the chromatographic conditions for the separation of arbutin and the conditions for the sample preparation of the raw material of Malus sylvestris leaves for HPLC analysis. According to the conducted studies, the content of arbutin should not be less than 0.7%.

The eruption of a large prominence that occurred away of active regions in the SOL2013-09-29 event produced a fast coronal mass ejection (CME) and a shock wave. The event caused considerable geospace disturbances, including a proton enhancement that have been addressed in previous studies. Continuing with the analysis of this event, we focus on the development of the CME and shock wave, assess an expected geospace impact using simplest considerations, and compare the expectations with in situ measurements near Earth. The high CME speed in this non-flare-associated event was determined by a considerable reconnected flux that corresponds to a pattern established by different authors. Estimations based on a few approaches showed the reconnection flux in this event to be comparable with a typical value in flare-associated eruptions. The shock wave was most likely impulsively excited by the erupting prominence in the same way as in flare-associated events and changed to the bow-shock regime later. The trajectory calculated for this scenario reproduces the Type II emission observed from 30 MHz to 70 kHz; its interruptions were probably caused by propagation effects. Properties of the near-Earth proton enhancement are discussed considering the results of recent studies.

The article contains the research of the authors in the field of jet propulsion systems with low energy consumption of small spacecraft (SSC) of nanosatellite class. The paper presents the concept of a Microdrive combining thermogasdynamic and electrodynamic methods of creating a jet thrust. We are talking about the propulsion system with resonance accelerating system, pre-heated and ionized working fluid. A toroidal volume resonator excited by a low-power solid-state microwave oscillator is considered as an accelerator. The work has experimental and theoretical components. The experimental part is devoted to the development of a method for transmitting microwave energy to a volume resonator from an oscillator. The theoretical part includes the calculation of the accelerating gap, the dimensions of the toroidal resonator, the estimation of the working fluid velocity after preheating and acceleration. This work is a continuation of works on creation of methodological bases for design correction engine micro thrust µa with microwave acceleration of the working body

Proposed method of energy parameters control of freight vehicles in a non-brake way is based on evaluation of their dynamic properties. An algorithm has been developed for calculating all the necessary energy parameters, on the basis of which analysis and correct technical and production operation of freight vehicles (FV) are carried out. The method of measuring speed and acceleration of FV was tested using a set of GPS and/or GLONASS sensors which showed its effectiveness.

The production of nitrogen from the air through membrane gas separation processes is widely used in many industries. The problem of controlling the gas separation process, it is connected with multi-loop control using the control of several variables. This article proposes an intelligent controller for matching fluctuations in pressure and airflow of the gas separator. The intelligent controller is based on a fuzzy logic algorithm. Applying fuzzy logic in the proposed solution allows you to increase the speed of the control system. The effectiveness of the proposed controller was evaluated in comparison with the PID controller. The proposed fuzzy controller can improve the accuracy of the control system of gas separation, reduce the process transient duration and increase the service life of technological equipment.

Intensive chemistry of agriculture has led to a number of negative phenomena associated with the development of erosion processes, deterioration of soil structure, pollution of soils, reservoirs and agricultural products by agrochemicals, which has affected its quality. Alongside with environmental problems, the issue of providing people with benign food products is dominant. At the present stage of development of agriculture and level of food security, significant innovations in the field of alternative agriculture, preservation of natural resources and, first of all, the main means of production - the land become significant updating. At the same time, the incomplete capacity of the organic products market and almost unlimited potential for the development of ecological production create all the necessary preconditions for increasing the competitiveness of domestic producers. Ukraine has a unique opportunity to take one of the leading places among producers of organic products in terms of its natural and climatic and soil potential. However, despite the progress in the development of organic production, in Ukraine there are a number of factors that hamper its development. One of the ways to overcome the problems of organic production is the introduction of geoinformation technologies to create a single database for the registration of organic enterprises. Geoinformation systems provide high-quality work with a lot of informative data. The creation of a registration base for the production of organic crop production will significantly affect the development of agriculture as a whole, thanks to the accuracy, volume and analysis of information that the system can operate. The purpose of the study was to develop the principles for creating a register of producers of organic crop production through the use of geoinformation systems, taking into account the soil and climate resources of Ukraine. In the work, cameral research methods were used using the DIGITAL, ARCGIS, ARSMAP and ARCCATALOG software platforms. The development of the registration base for organic enterprises was carried out on the example of SAD LLC, located in the Brovarsky district of the Kiev region. The way of creating and filling the registration base of enterprises engaged in organic production was justified. The main advantage of the established base over existing ones is the simplification of the land monitoring system and the introduction of the principle of rational use of land resources to reduce environmental risk and soil degradation. Due to the ARCMAP and ARCCATALOG software platforms, which are composite ARCGIS, a specific set of tools with a raster substrate for processing a particular territorial unit was created. The electronic map of the fields gives information about the exact area of the fields of any configuration, can reflect the length of the roads and their quality, shows the location of objects in space and allows, if necessary, to navigate to any specified point in any given trajectory. There are two main ways of creating electronic maps of fields that differ in the way of applying the boundaries of fields: 1) Vectorization of the boundaries of fields in high resolution space images; 2) bypassing (bypassing) the boundaries of fields using GPS equipment and special software; 3) vectorization of borders on existing paper maps of plans for intra-farm land management. In the latter case, it should be taken into account that in addition to the traditionally poor quality of raster scanning, boundary error errors will increase due to differences in the used coordinate systems. A combination of all these methods is possible. Next, an electronic geomorphological map is created. There are several variants of its creation: digitization of the topographic basis with the obtaining of a three-dimensional digital relief map or digitization of a pre-made manually on a paper topographic basis maps of forms and relief elements. The first version is more precise and supervised, and opens up wide opportunities for automatic design, however, it is often more laborious. The second option is less accurate, but much easier to execute. Digitization of the paper original can also be done in two ways: either manually rendering the contours on a registered topographic basis or a registered scanned card, or automatically using vectorizers digitizing the contour grid scanned from the tracing paper. The basic information is formed in the process of soil-landscape mapping of lands, carried out on materials of aerial photography, topographic maps and data of special field and laboratory research. The results of the surveys are presented in a layered form in the form of electronic maps of the forms and elements of the mesorelief, slope steepness, their exposure, microrelief, soil-forming rocks, hydrogeological conditions, soil erosion, soil structure, etc. Each electronic map has a database containing the corresponding map topics for each contour. An electronic map of the microstructures of the soil cover may contain the following information: contour number; Soil Combination Index; full name of the soil combination; the ratio of soils to the SPN, the degree of complexity and contrast, the position in the geochemical landscape, the geochemical barriers, the agro-ecological parameters of soils. All electronic maps have a single coordinate system, tied to a scanned topographic scale of 1: 10000 scale. In the future, the filling of the registration base with tools necessary for processing the territories at the regional and state levels will allow the introduction of free access to the search for the necessary information for new entrepreneurs, and will also simplify the registration of land plots. Key words: geoinformation systems, agro-ecological parameters of soils, registration base, electronic geomorphological map, topographic scale

The eruption of a large quiescent prominence on 17 August 2013 and associated coronal mass ejection (CME) were observed from different vantage points by Solar Dynamics Observatory (SDO), Solar-Terrestrial Relations Observatory (STEREO), and Solar and Heliospheric Observatory (SOHO). Screening of the quiet Sun by the prominence produced an isolated negative microwave burst. We estimated parameters of the erupting prominence from a model of radio absorption and measured from 304 \AA\ images. Their variations obtained by both methods are similar and agree within a factor of two. The CME development was studied from the kinematics of the front and different components of the core and their structural changes. The results are verified using movies in which the CME expansion was compensated according to the measured kinematics. We found that the CME mass ($3.6 \times 10^{15}$ g) was mainly supplied by the prominence ($\approx 6 \times 10^{15}$ g), while a considerable part drained back. The mass of the coronal-temperature component did not exceed $10^{15}$ g. The CME was initiated by the erupting prominence, which constituted its core and remained active. The structural and kinematical changes started in the core and propagated outward. The CME structures continued to form during expansion, which did not become self-similar up to $25 R_\odot$. The aerodynamic drag was insignificant. The core formed until $4 R_\odot$. Some of its components were observed to straighten and stretch forward, indicating the transformation of tangled structures of the core into a simpler flux rope, which grew and filled the cavity as the CME expanded., Comment: 29 pages, 10 figures. For associated movie files, see http://uafo.ru/solph.php Accepted for publication in Solar Physics

Heat transfer coefficient for cooling tower is determined experimentally and theoretically, the latent heat and air flow heat to are calculated. Thickness of heat layer is calculated and is then compared to theoretically calculated the displacement layer. The heat transfer coefficient is calculated based on the values of displacement layer and its deviation from theoretically calculated one is up to 3 times in the range of air velocity of 1.3-3.0 m/s. The difference in temperature of the air and water film is calculated.

Harmonic signal of a given frequency and amplitude is required for ultrasonic instrument operation.At a power output of 200 W there is a need to refine the scheme because of negative effects which could be neglected at lower power.This article shows an introduction of changes to the transformer switching circuit generating high power ultrasonic signal.

A solar eruptive event SOL2010-06-13 observed with SDO/AIA has been discussed in the contexts of the CME gebesis and an associated EUV transient in terms of a shock driven by the apparent CME rim. We have revealed in this event an erupting flux rope, studied its properties, and detected wave signatures inside the developing CME. These findings have allowed us to establish new features in the genesis of the CME and associated EUV wave and to reconcile all of the episodes into a causally-related sequence. (1) A hot 11 MK flux rope developed from a compact filament, accelerated up to 3 km/s$^2$ 1 min before a hard X-ray burst and earlier than other structures, reached 420 km/s, and decelerated to 50 km/s. (2) The CME development was driven by the flux rope. Closed structures above the rope got sequentially involved in the expansion from below upwards, came closer together, and disappeared to reveal their envelope, the rim, which became the outer boundary of the cavity. The rim was associated with the separatrix surface of a magnetic domain, which contained the pre-eruptive filament. (3) The rim formation was associated with a successive compression of the upper active-region structures into the CME frontal structure (FS). When the rim was formed, it resembled a piston. (4) The disturbance responsible for the CME formation was excited by the flux rope inside the rim, and then propagated outward. EUV structures at different heights started to accelerate, when their trajectories in the distance-time diagram were crossed by the front of this disturbance. (5) Outside the rim and FS, the disturbance propagated like a blast wave, manifesting in a type II radio burst and a leading part of the EUV transient. Its main, trailing part was the FS, which consisted of swept-up 2 MK loops enveloping the rim. The wave decelerated and decayed soon, being not driven by the trailing piston, which slowed down., 45 pages, 20 figures. For associated movie files, see http://ssrt.iszf.irk.ru/~grechnev/papers/flux-rope_progenitor_2010-06-13/ Accepted for publication in Solar Physics. The final publication is available at Springer via http://dx.doi.org/10.1007/s11207-016-0888-z

We show that a Moreton wave, an “EIT wave,” and a type II radio burst observed during a solar flare of July 13, 2004, might have been a manifestation of a single front of a decelerating shock wave, which appeared in an active region (AR) during a filament eruption. We propose describing a quasi-spheroidal wave propagating upward and along the solar surface by using relations known from a theory of a point-like explosion in a gas whose density changes along the radius according to a power law. By applying this law to fit the drop in density of the coronal plasma enveloping the solar active region, we first managed to bring the measured positions and velocities of surface Moreton wave and “EIT wave” into correspondence with the observed frequency drift rate of the meter type II radio burst. The exponent of the vertical coronal density falloff is selected by fitting the power law to the Newkirk and Saito empirical distributions in the height range of interest. Formal use of such a dependence in the horizontal direction with a different exponent appears to be reasonable up to distances of less than 200 Mm around the eruption center. It is possible to assume that the near-surface shock wave weakens when leaving this radius and finally the active region, entering the region of the quiet Sun where the coronal plasma density and the fast-mode speed are almost constant along the horizontal.

We show examples of excitation of coronal waves by flare-related abrupt eruptions of magnetic rope structures. The waves presumably rapidly steepened into shocks and freely propagated afterwards like decelerating blast waves that showed up as Moreton waves and EUV waves. We propose a simple quantitative description for such shock waves to reconcile their observed propagation with drift rates of metric type II bursts and kinematics of leading edges of coronal mass ejections (CMEs). Taking account of different plasma density falloffs for propagation of a wave up and along the solar surface, we demonstrate a close correspondence between drift rates of type II bursts and speeds of EUV waves, Moreton waves, and CMEs observed in a few known events., Comment: 30 pages, 15 figures. Solar Physics, published online. The final publication is available at http://www.springerlink.com

Solar events of June 15/16, 2000, June 1/2, 2002, February 6, 2002, and February 7, 2002, have been studied. These events probably belong to a poorly studied class of explosive eruptions. In such events disintegration of the magnetic structure of an eruptive filament and dispersing of its fragments as a cloud over a considerable part of the solar surface are possible. The analysis of SOHO/EIT extreme ultraviolet images obtained in the 195 A and 304 A channels has revealed the appearance of dimmings of various shapes and propagation of a coronal wave for June 1/2, 2002. In all the events the Nobeyama, Learmonth, and Ussuriysk observatories recorded negative radio bursts at several frequencies in the 1–10 GHz range. Most likely, these bursts were due to absorption of solar radio emission in clouds produced by fragments of filaments. Absorption of the solar background radiation can be observed as a depression of the emission in the 304 A channel. A model has been developed, which permits one to estimate parameters of absorbing plasma such as temperature, optical thickness, area of the absorbing cloud, and its height above the chromosphere from the radio absorption observed at several frequencies. The obtained values of the temperature, 8000–9000 K, demonstrate that the absorber was the material of an erupted cool filament. The model estimate of the masses of the ejecta in the considered events were ∼1015 g, which is comparable to masses of typical filaments and coronal mass ejections.

We present a case study of the 13 July 2004 solar event, in which disturbances caused by eruption of a filament from an active region embraced a quarter of the visible solar surface. Remarkable are absorption phenomena observed in the SOHO/EIT 304 A channel; they were also visible in the EIT 195 A channel, in the H-alpha line, and even in total radio flux records. Coronal and Moreton waves were also observed. Multi-spectral data allowed reconstructing an overall picture of the event. An explosive filament eruption and related impulsive flare produced a CME and blast shock, both of which decelerated and propagated independently. Coronal and Moreton waves were kinematically close and both decelerated in accordance with an expected motion of the coronal blast shock. The CME did not resemble a classical three-component structure, probably, because some part of the ejected mass fell back onto the Sun. Quantitative evaluations from different observations provide close estimates of the falling mass, ~3 10^15 g, which is close to the estimated mass of the CME. The falling material was responsible for the observed large-scale absorption phenomena, in particular, shallow widespread moving dimmings observed at 195 A. By contrast, deep quasi-stationary dimmings observed in this band near the eruption center were due to plasma density decrease in coronal structures., 30 pages, 16 Postscript figures. Solar Physics, in press. The original publication is available at http://www.springerlink.com/

Multi-instrument observations of two filament eruptions on 24 February and 11 May 2011 suggest the following updated scenario for eruptive flare, CME and shock wave evolution. An initial destabilization of a filament results in stretching out of magnetic threads belonging to its body and rooted in the photosphere along the inversion line. Their reconnection leads to i) heating of parts of the filament or its environment, ii) initial development of the flare arcade cusp and ribbons, and iii) increasing similarity of the filament to a curved flux rope and its acceleration. Then the pre-eruption arcade enveloping the filament gets involved in reconnection according to the standard model and continues to form the flare arcade and ribbons. The poloidal magnetic flux in the curved rope developing from the filament progressively increases and forces its toroidal expansion. This flux rope impulsively expands and produces an MHD disturbance, which rapidly steepens into a shock. The shock passes through the arcade expanding above the filament and then freely propagates ahead of the CME like a decelerating blast wave for some time. If the CME is slow, then the shock eventually decays. Otherwise, the frontal part of the shock changes into the bow-shock regime. This was observed for the first time in the 24 February 2011 event. When reconnection ceases, the flux rope relaxes and constitutes the CME core-cavity system. The expanding arcade develops into the CME frontal structure. We also found that reconnection in the current sheet of a remote streamer forced by the shock's passage results in a running flare-like process within the streamer responsible for a type II burst. The development of dimming and various associated phenomena are discussed., Comment: 35 pages, 16 figures. For associated movie files, see http://ssrt.iszf.irk.ru/~grechnev/papers/responsibility_cmes_shocks/ Accepted for publication in Solar Physics. The final publication is available at Springer via http://dx.doi.org/10.1007/s11207-014-0621-8

An analysis of temperature-dependent shifts and widths of Davydov-split spectral lines for local vibrations in the 2×1 phase of CO/NaCl(100) demonstrates that presently accepted theories which neglect the low frequency mode collectivization for adsorbed molecules fail to account for this temperature dependence. To provide an adequate description for collectivized modes, a simple formula is proposed which includes, in addition to standard parameters of the dephasing model, another one, the effective half-width of the low frequency vibration band. As a result, a self-consistent treatment of spectroscopic data and a parameter determination for the systems studied become possible.

It is shown that, by varying the angular size of a collimator, the spectral distribution of parametric x-ray radiation can be split into two isolated peaks and that the center of the spectral distribution of this radiation is shifted in frequency in response to an increase in the collimator size. It is also predicted that an increase in the angular size of the collimator will lead to a substantial modification of the character of the orientation dependence of the radiation spectrum.

We investigate anharmonically coupled high- and low-frequency excitations in a planar lattice of adsorbed molecules interacting with phonons of a crystal. Dephasing of high-frequency local vibrations by low-frequency resonance modes is described in terms of temperature Green's function. The equations obtained are solved, first, with a small ratio of the anharmonic coupling coefficient for high- and low-frequency modes to the resonance width, and second, in the low-temperature limit. High-frequency spectral line positions and widths depend on dispersion laws and resonance mode lifetimes. It is shown that lateral interactions of low-frequency modes of adsorbed molecules can lead to a significant narrowing of high-frequency spectral lines, which is consistent with experimental data., REVTeX, 11 pages, no figures

Low-temperature plasma ejected in solar eruptions can screen active regions as well as quiet solar areas. Absorption phenomena can be observed in microwaves as 'negative bursts' and in different spectral domains. We analyze two very different recent events with such phenomena and present an updated systematic view of solar events associated with negative bursts. Related filament eruptions can be normal, without essential changes of shape and magnetic configuration, and 'anomalous'. The latter are characterized by disintegration of an eruptive filament and dispersal of its remnants as a cloud over a large part of solar disk. Such phenomena can be observed as giant depressions in the He II 304 A line. One of possible scenarios for an anomalous eruption is proposed in terms of reconnection of filament's internal magnetic fields with external large-scale coronal surrounding., Comment: 11 pages, 8 figures, 1 table. Accepted for publication in PASJ

Plasma with a temperature close to the chromospheric one is ejected in solar eruptions. Such plasma can occult some part of emission of compact sources in active regions as well as quiet solar areas. Absorption phenomena can be observed in the microwave range as the so-called 'negative bursts' and also in the He II 304 A line. The paper considers three eruptive events associated with rather powerful flares. Parameters of absorbing material of an eruption are estimated from multi-frequency records of a 'negative burst' in one event. 'Destruction' of an eruptive filament and its dispersion like a cloud over a huge area observed as a giant depression of the 304 A line emission has been revealed in a few events. One such event out of three ones known to us is considered in this paper. Another event is a possibility., Comment: 23 pages, 8 figures, submitted for publication in Astronomy Reports

During deformation of Al samples, the sample electric resistance is measured, which near the superconducting transition is very sensitive to slight temperature and magnetic field variations. This property allows the sample to be used as a thermometer, so that its temperature can be measured during deformation. By this method the heating of the sample over the coolant environment is measured, and the possibility of Cooper pair break-up by moving dislocations in the superconductor is investigated. The study used aluminium single and polycrystals of two purities (99.999 and 99.5%) with various strain rates at temperatures from 0.6 to 1.2 K. Der elektrische Widerstand von Al-Proben wird wahrend der Deformation gemessen, er reagiert in der Nahe des supraleitenden Uberganges sehr empfindlich auf geringfugige Anderungen der Temperatur und des Magnetfeldes. Aufgrund dieser Eigenschaft kann die Probe als Thermometer benutzt werden, so das die Temperatur wahrend der Deformation gemessen werden kann. Mit dieser Methode wird die Aufheizung der Probe uber die Umgebungstemperatur festgestellt, und die Moglichkeit des Aufbrechens von Cooper-Paaren durch wandernde Versetzungen im Supraleiter untersucht. Aluminium-Ein- und -Polykristalle in zwei Reinheitsgraden (99,999 und 99,5%) werden bei verschiedenen Verformungsgeschwindigkeiten und Temperaturen zwischen 0,6 und 1,2 K untersucht.