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Hemp is predominantly a source of raw material for fiber production. However, hemp oil is also of particular interest, as it is characterized by rare nutritional and medicinal properties. One of the methods that improve the hemp oil quality is the application of microelement fertilizers, which are characterized by low cost, high efficiency and environmental safety. Therefore, the purpose of the research is to study the effect of the period of foliar treatment of technical hemp with microelement fertilizers on the oil content and its fatty acid composition. The oil accumulation is most affected by K - Humate - Na with trace elements and Agree`s "Magnesium", where its content on average over two years was 33.0 %. The greatest effect on oil accumulation was after double foliar top dressing, while the oil content of the seeds reached 32.7%. In hemp oil, 18 fatty acids have been identified, and their proportion in quantitative terms has also been established. The share of hard-to-digest saturated fatty acids accounts for 9.446%. The total content of polyunsaturated fatty acids was 70.503% with a predominance of linoleic (55.65%) and ?-linolenic (14.853%) acids. Of the monounsaturated ones, oleic acid is the most represented (15.033%). In hemp oil, the most favorable ratio of ?-6 and ?-3 unsaturated fatty acids is 3.7: 1, which corresponds to the recommendations of the Institute of Nutrition of the Russian Academy of Medical Sciences for the diet of a healthy person.

We present new isochrone fits to the colour-magnitude diagrams of the Galactic globular clusters NGC\,6362 and NGC\,6723. We utilize 22 and 26 photometric filters for NGC\,6362 and NGC\,6723, respectively, from the ultraviolet to mid-infrared using data sets from {\it HST}, {\it Gaia}, unWISE, and other photometric sources. We use models and isochrones from the Dartmouth Stellar Evolution Database (DSED) and Bag of Stellar Tracks and Isochrones (BaSTI) for $\alpha$-enhanced [$\alpha$/Fe]$=+0.4$ and different helium abundances. The metallicities [Fe/H]$=-1.04\pm0.07$ and $-1.09\pm0.06$ are derived from the red giant branch slopes in our fitting for NGC\,6362 and NGC\,6723, respectively. They agree with spectroscopic estimates from the literature. We find a differential reddening up to $\Delta E(B-V)=0.13$ mag in the NGC\,6723 field due to the adjacent Corona Australis cloud complex. We derive the following for NGC\,6362 and NGC\,6723, respectively: distances $7.75\pm0.03\pm0.15$ (statistic and systematic error) and $8.15\pm0.04\pm0.15$ kpc; ages $12.0\pm0.1\pm0.8$ and $12.4\pm0.1\pm0.8$ Gyr; extinctions $A_\mathrm{V}=0.19\pm0.04\pm0.06$ and $0.24\pm0.03\pm0.06$ mag; reddenings $E(B-V)=0.056\pm0.01\pm0.02$ and $0.068\pm0.01\pm0.02$ mag. DSED provides systematically lower [Fe/H] and higher reddenings than BaSTI. However, the models agree in their relative estimates: NGC\,6723 is $0.44\pm0.04$ kpc further, $0.5\pm0.1$ Gyr older, $\Delta E(B-V)=0.007\pm0.002$ more reddened, and with $0.05\pm0.01$ dex lower [Fe/H] than NGC\,6362. The lower metallicity and greater age of NGC\,6723 with respect to NGC\,6362 explain their horizontal branch morphology difference. This confirms age as the second parameter for these clusters. We provide lists of the cluster members from the {\it Gaia} Data Release 3., Comment: Accepted to be published in MNRAS, 20 pages, 3 online tables

We present the biggest up-to-date sample of edge-on galaxies with boxy/peanut-shaped (B/PS) bulges and X-structures. The sample was prepared using images from the Dark Energy Spectroscopic Instrument (DESI) Legacy catalogue and contains about 2000 galaxies. To find suitable candidates in catalogue, we made the assumption that the residues (original images minus model) of galaxies with B/PS bulges should exhibit a characteristic X-shape. Galaxies with such features were selected by eye and then used as input data for a neural network training, which was applied to a bigger sample of edge-on galaxies. Using the available data and the photometric models from the literature, we investigated the observational and statistical properties of the sample created. Comparing the B/D ratios for galaxies with and without B/PS bulges, we found that the B/D ratio for galaxies from our sample is statistically higher, with typical values in the range ≈0.2–0.5 depending on the decomposition procedure. We studied how the opening angles φ of the X-structure and the length of its rays are distributed in the formed sample and found them to be consistent with previous measurements and predictions from N-body models, e.g. $\varphi \gtrsim 25{^\circ }$, but measured here for a much larger number of galaxies. We found a sharp increase in the B/PS bulge fraction for stellar masses log M⋆ ≳ 10.4, but for edge-on galaxies, which complements the results of previous works. The sample can be used in future work to test various bar models and their relationship with B/PS bulges, as well as to study their stability and evolution.

The paper presents the history of the transport infrastructure of the West-Siberian oil and gas complex in the last century and ways to solve the problems of road construction in the twenty-first century. The development of the territory of Siberia and the North in the present period is constrained by the low rates of development of the transport structure. One of the reasons for this lag is the lack of regulatory documents to substantiate transport structures in the harsh climatic and difficult soil and geological conditions based on the use of new modern road-building materials. The development of new resource-saving materials, structures and technologies based on local building materials, products and industrial waste using modern methods and research methods in materials science is an aim of current study. The general research methodology consisted of theoretical, laboratory and field studies. The developed designs and technologies for the construction of embankments in permafrost and in swamps using geotechnical holders filled with unsuitable soils (thawed and frozen waterlogged peat and clay soils) can reduce the volume of work and the cost of construction by one and a half to two times while increasing the service life of structures. The experimental sites of embankments constructed between 1995 and 2009 in the wetlands of the Uvat Group of deposits in the Tyumen Region and in permafrost in the areas of Novy Urengoy have been observed for more than ten years. The artificial stone material tested in Murmansk and Surgut based on the strengthening of local soils with inorganic binders with polymer additives using modern technologies allows it to be used instead of imported stone materials and reinforced concrete slabs for the construction of structural layers of road pavements, reinforcing slopes, as well as in hydraulic structures. The new artificial stone material is characterized by high strength and durability in areas with a temperature gradient of the external environment of more than 100 (from +50 to -50 °C).

We study the bulk radical polymerization of methyl methacrylate (MMA) in the presence of bis(1,1,5,5-tetraethyl-2,4-dithiobiureto)cadmium(II) [Cd(N(SCNEt2)2)2] (TEDBCd) used as the precursor of CdS nanoparticles. This compound is readily soluble both in MMA monomer and in polymethyl methacrylate (PMMA). The bulk samples based on PMMA containing up to 7% of this cadmium compound are visually transparent and colorless. We study thermal and optical properties of the obtained composites. UV irradiation of bulk composites based on the PMMA matrix with TEDBCd results in the formation of luminescent pattern containing CdS nanoparticles, which is proved by TEM and HRTEM analysis.

The HERON project is aimed at studying haloes and low surface brightness details near galaxies. In this second HERON paper we consider in detail deep imaging (down to surface brightness of ∼28 mag/arcsec2 in the r band) for 35 galaxies, viewed edge-on. We confirm a range of low surface brightness features previously described in the literature but also report new ones. We classify the observed outer shapes of the galaxies into three main types (and their prototypes): disc/diamond-like (NGC 891), oval (NGC 4302), and boxy (NGC 3628). We show that the shape of the outer disc in galaxies does not often follow the general 3D model of an exponential disc: 17 galaxies in our sample exhibit oval or even boxy isophotes at the periphery. Also, we show that the less flattened the outer disc is, the more oval or boxy its structure. Many galaxies in our sample have an asymmetric outer structure. We propose that the observed diversity of the galaxy outer shapes is defined by the merger history and its intensity: if no recent multiple minor or single major merging took place, the outer shape is diamond-like or discy. On the contrary, interacting galaxies show oval outer shapes, whereas recent merging appears to transform the outer shape to boxy.© 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society, We thank the anonymous reviewer for helpful comments on the paper. This research has made use of the NASA/IPAC Infrared Science Archive (IRSA; http://irsa.ipac.caltech.edu/frontpage/), and the NASA/IPAC Extragalactic Data base (NED; https://ned.ipac .caltech.edu/), both of which are operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This research has made use of the HyperLeda data base (http://leda.univ-lyon1.fr/; Makarov et al. 2014). This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. RMR acknowledges financial support from his late father Jay Baum Rich. JR acknowledges financial support from the State Agency for Research of the Spanish MCIU through the ‘Center of Excellence Severo Ochoa’ award to the Instituto de Astrof´ısica de Andaluc´ıa (SEV-2017-0709) and support from the grant RTI2018-096228-B-C31 (MICIU/FEDER, EU). PU acknowledges financial support from the Russian Science Foundation (grant no. 19-12-00145)

We present a detailed analysis of the Galaxy structure using an unWISE wide-field image at $3.4\mu$m. We perform a 3D photometric decomposition of the Milky Way taking into account i) the projection of the Galaxy on the celestial sphere and ii) that the observer is located within the Galaxy at the solar radius. We consider a large set of photometric models starting with a pure disc model and ending with a complex model which consists of thin and thick discs plus a boxy-peanut-shaped bulge. In our final model, we incorporate many observed features of the Milky Way, such as the disc flaring and warping, several over-densities in the plane, and the dust extinction. The model of the bulge with the corresponding X-shape structure is obtained from N-body simulations of a Milky Way-like galaxy. This allows us to retrieve the parameters of the aforementioned stellar components, estimate their contribution to the total Galaxy luminosity, and constrain the position angle of the bar. The mass of the thick disc in our models is estimated to be 0.4-1.3 of that for the thin disc. The results of our decomposition can be directly compared to those obtained for external galaxies via multicomponent photometric decomposition., Comment: 19 pages, 10 figures, Accepted for publication in MNRAS

Photo-induced nanocomposites are initially transparent polymeric materials having specially designed precursor molecules. UV irradiation leads to the precursor destruction followed by the growth of nanoparticles within the initially homogeneous media. We demonstrate that combining an UV LED and a white LED is a very effective tool for both the UV induced formation of nanoparticles within a polymer film and in situ monitoring of the evolution of the absorbance spectra, which is indicative of the nanoparticle growth.

Metal or semiconductor nanoparticles (NPs) can be instantly generated in polymers under the irradiation by light, thus converting them into the photoinduced nanocomposites. The light causes the photodestruction of the precursor molecules dissolved in the polymer matrix. As a result, some kind of elementary species (such as atoms of metal) are released and then precipitate into the NPs right within the bulk of the material. This paper considers theoretically the kinetics of the localized NP generation under the prolonged irradiation by the focused continuous-wave or pulsed laser light. It is shown that the maximal rate at which the elementary species can be generated by the laser beam is determined by the balance between the depletion rate of the precursor within the irradiated spot and its diffusion flux from the surrounding volume. The optimal beam power that yields the maximal species generation rate at the focus is calculated. At that and smaller beam power, the maximum material modification is located at the maximum of the laser intensity. With the higher beam power, the material modification can be performed within the hollow volume, leaving the focus untouched. The possibility of the local generation of NPs is studied within the framework of the simplest homogenous nucleation model. The locally generated elementary species tend to leave the irradiated zone due to the diffusion. However, if the initial precursor concentration is high enough, the growing NPs act as traps for elementary species thus impeding this delocalization effect.

Applying spectral dynamics methods to one typical $N$-body model with a barlens, we dissect the modelled bar into separate components supported by completely different types of orbits. We identify at least four components: a narrow elongated bar, a boxy bar, and two components contributing to the barlens. We analyse the vertical structure of all components that make up the thick part of the bar, which has a boxy/peanut shape (B/P bulge). We show that the `peanut' shape is mainly due to the orbits that assemble the boxy part of the face-on bar. We associate the X-shape with the narrow and elongated bar. The wider part of the barlens with square-like isophotes contributes to the boxy shape of the B/P bulge when we observe the galaxy edge-on. However, the part of the barlens with rounded isophotes in the face-on view is a rather flat structure in the vertical direction without any significant off-centre protrusions. Thus, for the first time, we demonstrate that the rounded face-on barlens cannot be entirely associated with the B/P bulge., Comment: 5 pages, 5 figures, accepted to Astronomy and Astrophysics on March 26, 2021

We present new isochrone fits to colour-magnitude diagrams of the Galactic globular clusters NGC\,288, NGC\,362, and NGC\,6218 (M12). We utilize a lot of photometric bands from the ultraviolet to mid-infrared by use of data from the {\it HST}, {\it Gaia}, unWISE, Pan-STARRS, and other photometric sources. In our isochrone fitting we use theoretical models and isochrones from the Dartmouth Stellar Evolution Program and Bag of Stellar Tracks and Isochrones for $\alpha$-enhanced abundance [$\alpha$/Fe]$=+0.40$, different helium abundances, and a metallicity of about [Fe/H]$=-1.3$ adopted from the literature. We derive the most probable distances $8.96\pm0.05$, $8.98\pm0.06$, and $5.04\pm0.05$ kpc, ages $13.5\pm1.1$, $11.0\pm0.6$, and $13.8\pm1.1$ Gyr, extinctions $A_\mathrm{V}=0.08\pm0.03$, $0.11\pm0.04$, and $0.63\pm0.03$ mag, and reddenings $E(B-V)=0.014\pm0.010$, $0.028\pm0.011$, and $0.189\pm0.010$ mag for NGC\,288, NGC\,362, and NGC\,6218, respectively. The distance estimates from the different models are consistent, while those of age, extinction, and reddening are not. The uncertainties of age, extinction, and reddening are dominated by some intrinsic systematic differences between the models. However, the models agree in their relative age estimates: NGC\,362 is $2.6\pm0.5$ Gyr younger than NGC\,288 and $2.8\pm0.5$ Gyr younger than NGC\,6218, confirming age as the second parameter for these clusters. We provide reliable lists of the cluster members and precise cluster proper motions from the {\it Gaia} Early Data Release 3., Comment: 19 pages, 16 figures, accepted to MNRAS

The article continues the series of publications developing new statistically motivated approach to data clustering. Proposed method is applied for searching clusters of increased or decreased frequencies of some events in sets of neighboring cells in two dimensional tessellations of plane. Such cells may correspond to administrative regions, counties etc. The case of simple frequency tables (histograms) with rectangular cells was considered earlier. The observed distribution of event frequencies in cells can be compared either with expected one (for instance uniform) or with distribution corresponding to the previous moment of time. The groups of neighboring cells with the same direction of changes are unified in clusters which are checked to be statistically significant with account on multiple comparisons. Each group of cells is characterized with two parameters – its size (the number of cells) and the intensity of changing. If the size of group or (and) its intensity are too pronounced then such group is considered to be statistically significant cluster. There are no a priori suggestions concerning the number, size or shape of potentially existing clusters. Method can be used for clustering any multidimensional arrays of p-values which are independent and uniformly distributed according null hypothesis, while alternative is that there are sets of neighboring cells where p-values are close to 0 or to 1.

The geometric characteristics of dust clouds provide important information on the physical processes that structure such clouds. One of such characteristics is the 2D fractal dimension D of a cloud projected on to the sky plane. In previous studies, which were mostly based on infrared (IR) data, the fractal dimension of individual clouds was found to be in a range from 1.1 to 1.7 with a preferred value of 1.2-1.4. In this work, we use data from Stripe82 of the Sloan Digital Sky Survey to measure the fractal dimension of the cirrus clouds. This is done here for the first time for optical data with significantly better resolution as compared to IR data. To determine the fractal dimension, the perimeter-area method is employed. We also consider IR (IRAS and Herschel) counterparts of the corresponding optical fields to compare the results between the optical and IR. We find that the averaged fractal dimension across all clouds in the optical is $\langle D \rangle =1.69{+0.05} {-0.05}$ which is significantly larger than the fractal dimension of its IR counterparts $\langle D\rangle =1.38{+0.07} {-0.06}$. We examine several reasons for this discrepancy (choice of masking and minimal contour level, image and angular resolution, etc.) and find that for approximately half of our fields the different angular resolution (point spread function) of the optical and IR data can explain the difference between the corresponding fractal dimensions. For the other half of the fields, the fractal dimensions of the IR and visual data remain inconsistent, which can be associated with physical properties of the clouds, but further physical simulations are required to prove it. © 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society., We acknowledge financial support from the Russian Science Foundation (grant no. 20-72-10052). Funding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions. SDSS-IV acknowledges support and resources from the Center for High Performance Computing at the University of Utah. The SDSS website is www.sdss.org., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.

Based on the spectral analysis of individual orbits of stars from different $N$-body models, we show that the face-on morphology of the so-called `face-on peanut' bars (boxy bars) and barlenses is supported by different types of orbits. For `face-on peanut' bars, the so-called boxy orbits come to the fore, and they are responsible for the unusual morphology of the bar in the central regions. In the models with compact bulges, the bars show a barlens morphology in their central parts. We found that the barlens supporting orbits come in two types, one of which gives a square-like shape and the other have a rosette-like shape in the frame co-rotating with the bar. Such a shape is typical for orbits around stable loop orbits in nearly axisymmetric potentials only slightly distorted by the bar. They were already known from some of the previous studies but their role in barlens shaping was barely investigated. Although quite simple, the rosette-like orbits are found to be the main building block of a barlens in our models. The detailed analysis of all bar orbits also allowed us to distinguish the x2 orbital family and isolate the structure supported by orbits trapped around this family. The x2 family is well-known, but, apparently, for the first time in $N$-body models we have revealed the structure it supports by means of spectral dynamics and highlight its contribution to the barlens. We found that the x2 family population increases with an increase in central matter concentration., Published in MNRAS

X-structures are often observed in galaxies hosting the so-called B/PS (boxy/peanuts) bulges and are visible from the edge-on view. They are the most notable features of B/PS bulges and appear as four rays protruding from the disk of the host galaxy and distinguishable against the B/PS bulge background. In some works their origin is thought to be connected with the so-called banana-shaped orbits with a vertical resonance 2:1. A star in such an orbit performs two oscillations in the vertical direction per one revolution in the bar frame. Several recent studies that analyzed ensembles of orbits arising in different $N$-body models do not confirm the dominance of the resonant 2:1 orbits in X-structures. In our work we analyze two $N$-body models and show how the X-structure in our models is gradually assembled from the center to the periphery from orbits with less than 2:1 frequency ratio. The most number of such orbits is enclosed in a 'farfalle'-shape (Italian pasta) form and turns out to be non-periodic. We conclude that the X-structure is only the envelope of regions of high density caused by the crossing or folding of different types of orbits at their highest points, and does not have a "backbone" similar to that of the in-plane bar. Comparing the orbital structure of two different numerical models, we show that the dominance of one or another family of orbits with a certain ratio of the vertical oscillations frequency to the in-plane frequency depends on the parameters of the underlying galaxy and ultimately determines the morphology of the X-structure and the opening angle of its rays., Accepted for publication in ApJ

Materials based on copolymers of isobornylacrylate (IBA) with methylmethacrylate (MMA) or acrylonitrile (AN) have been synthesized by radical copolymerization using monomeric mixtures with different composition. The copolymer compositions were determined and relative activities of monomers were calculated by different methods. All copolymers have transparency up to 80% in the ultraviolet region. The mechanical and thermophysical properties of the copolymers depend on composition. The best combination of optical transparency and tensile strength is achieved in the copolymers containing 13% and 49% units of IBA (in the case of MMA and AN, respectively. The prospects of application of the copolymers as a matrix for creating photoinduced nanocomposites containing CdS are shown. Using the specially selected compounds of cadmium, materials with new optical properties were obtained by UV irradiation.

Tilted and warped discs inside tilted dark matter haloes are predicted from numerical and semi-analytical studies. In this paper, we use deep imaging to demonstrate the likely existence of tilted outer structures in real galaxies. We consider two SB0 edge-on galaxies, NGC4469 and NGC4452, which exhibit apparent tilted outer discs with respect to the inner structure. In NGC4469, this structure has a boxy shape, inclined by $\Delta$PA$\approx$3$^{\circ}$ with respect to the inner disc, whereas NGC4452 harbours a discy outer structure with $\Delta$PA$\approx$6$^{\circ}$. In spite of the different shapes, both structures have surface brightness profiles close to exponential and make a large contribution ($\sim30$%) to the total galaxy luminosity. In the case of NGC4452, we propose that its tilted disc likely originates from a former fast tidal encounter (probably with IC3381). For NGC4469, a plausible explanation may also be galaxy harassment, which resulted in a tilted or even a tumbling dark matter halo. A less likely possibility is accretion of gas-rich satellites several Gyr ago. New deep observations may potentially reveal more such galaxies with tilted outer structures, especially in clusters. We also consider galaxies, mentioned in the literature, where a central component (a bar or a bulge) is tilted with respect to the stellar disc. According to our numerical simulations, one of the plausible explanations of such observed "tilts" of the bulge/bar is a projection effect due to a not exactly edge-on orientation of the galaxy coupled with a skew angle of the triaxial bulge/bar., Comment: 20 pages, 19 figures, Accepted for publication in MNRAS

The instability of anisotropic disk systems with elongated stellar orbits has been investigated. N-body generalized polytropic models of stellar disks have been constructed. They are shown to be unstable with respect to the bar formation at any degree of anisotropy. This result differs from the results of the studies of such models by other authors. The bar pattern speed and amplitude have been found. The initial distribution of precession rates and the adiabatic invariants of stellar orbits have been calculated. A bar is shown to be formed in such systems due to the radial orbit instability.

By means of self-consistent numerical simulations we investigated the dynamical impact of classical bulges on the growth of the secondary buckling of a bar. Overall we considered 14 models with different disc and bulge parameters. We obtained that a bulge with a quite modest mass $B/D=0.1$ leads to completely symmetrical evolution of the bar almost independently of the initial stellar disc parameters and even can damp the first bending. At the same time, the bars in all our bulgeless models suffer from the short primary and prolonged secondary buckling. Given the smallness of the mass suppressing secondary buckling, we conclude that a classical bulge along with the gas central concentration may be the main culprits for the rarity of bars with ongoing buckling in the local Universe., Comment: Accepted for publication in MNRAS

Gaining control over the spatial distribution of nanoparticles in composite polymer materials is a relevant goal for a range of nanotechnology applications. Promising methods to produce nanoparticles directly in the polymer matrix rely on their self-assembly from the atoms that are generated due to the photodestruction of the precursor additive. Such materials are known as photoinduced nanocomposites. In this work, we theoretically study the possibility of producing tailored nanoparticle distributions in such materials by the local modification of their physical properties. For instance, laser irradiation may cause a permanent free-volume expansion (laser swelling), which results in a substantial change in the diffusivity of the aggregating atoms. The modeling shows that the nanoparticles tend to accumulate in the domains where the diffusivity is greater. Additionally, the variation of the matrix properties may result in spatial modulation of the atom-matrix interaction energy and thus modulation of the atom solubility in the matrix. This phenomenon can also affect the NP spatial distribution. This paper formulates the problem of the precipitation phase transition from the supersaturated solution in a polymer solvent which is "frozen" in the spatially nonuniform state. The basic traits of this phenomenon are studied by means of an analytical model. Then the NP growth is simulated using a lattice model.

We study the thermo-physical and photoluminescence (PL) properties of cadmium-(bis)dodecylthiolate (Cd(C12H25S)2). Significant attention is drawn to characterization of Cd(C12H25S)2 by different methods. The laser-induced PLs of Cd(C12H25S)2 and Cd(C12H25S)2/(polymethyl methacrylate) (PMMA) composites are studied. Samples of Cd(C12H25S)2/PMMA are synthesized by the polymerization method. Ultraviolet (UV)-pulsed laser irradiation of the samples under relatively small fluences leads to the formation of induced PL with the maximum near the wavelength of 600 nm. This process can be attributed to the transformation of Cd(C12H25S)2 within the precursor grains. Another PL peak at 450–500 nm, which appears under the higher fluences, relies on the formation of CdS complexes with a significant impact of the polymer matrix.

The model of TCP-connections processing for steganographic data transfer in informationtelecommunication networks has been proposed in this article. The requirements for the modification of the TCP for correct working of the steganographic system has been defined. The functioning of steganographic system when forming and sending of steganographic containers, receiving and extracting of messages has been considered in details. The notions of informative and uninformative values, which calculated during of search of correlations the symbols of open-text (the payload of TCP) with the symbols of the message has been introduced. The model includes blind marking, the implementation of which corresponds to the end of the process of sending (receiving) messages. Justified the lack of time delays in the functioning of the modified TCP relative to its standard version

The bactericidal effect of laser radiation with a quartz fiber-based transmission system with a strong absorption coating converter against bacteria associated with urological stones has been studied. Gram-negative rod Escherichia coli and the Gram-positive coccus Staphylococcus epidermidis, Staphylococcus aureus, Enterococcus faecalis and Enterococcus faecium were used in this study. Each bacterial species was treated by continuous-wave near infrared laser coupled with bare fiber tip or strongly absorption coating fiber tip. After treatment, the temperature of bacterial suspension was measured. In addition, the temperature distribution was analyzed. It has been shown that using laser with a strongly absorption coating fiber tip results in significant bactericidal effect. The decrease of the amount of E. coli and S. epidermidis was 100% after treatment with an output power of 6[Formula: see text]W of radiation at a wavelength of 0.97[Formula: see text][Formula: see text]m for 40[Formula: see text]s. Number of S. aureus and Ent. faecium colony-forming unit was reduced to 70% after same exposure. The peak temperature of bacterial suspension was [Formula: see text]C after treatment by laser with a strongly absorption coating fiber tip. Laser with a strongly absorption coating fiber tip provides large-scale hydrodynamic flows directed away from the fiber tip. The laser with a strongly absorption coating fiber tip has bactericidal effect. The main role is associated with the effect of high temperature, which, in the form of flow in a liquid medium, affects bacteria.

Photoinduced nanocomposites are the polymer materials where the nanoparticles can be generated by the light irradiation. The single atoms of metal are formed due to the photoreduction of the metal-containing precursor added to the polymer matrix. Then the atoms precipitate into the nanoparticles (NPs). Similarly, semiconductor NPs are assembled from the monomer species such as CdS, which can be released due to the photodestruction of the appropriate precursor. We analyze theoretically the possibility of spatial confinement of growing nanoparticles in a domain where the elementary species are generated by a three-dimensionally localized source. It is shown that the effective confinement can be achieved only if the size of the generation domain exceeds some critical spatial scale determined by the parameters of the system. The confinement is provided by the trapping of the diffusing elementary species by the growing nanoparticles. The proposed model considers the irreversible particle growth, typical for the noble metals. Both the nucleation and the particle growth processes are suggested to be diffusion controlled.

Recent observational studies of X-shaped structures revealed that values of their opening angles lie in a narrow range: from 20 deg to 43 deg with smaller X-shaped structures appearing to follow a characteristic opening angle ~ 27 deg - 31 deg. We use self-consistent numerical simulations to uncover what parameters of host galaxies govern the opening angle spread. We constructed a series of equilibrium models of galaxies with high spatial resolution, varying the dark halo and bulge contribution in the overall gravitational potential, the initial disc thickness of models and the Toomre parameter Q and followed their evolution for almost 8 Gyrs. Each model demonstrated the formation of clear X-structures with different flatness. We have obtained that opening angles lie in the range from 25 deg to 42 deg throughout the entire evolution. These values are roughly consistent with observational data. The greatest variation in the opening angles is obtained by varying the mass of the dark halo. The initial thickness of the disc and the Toomre parameter are responsible for smaller variations of the angle and shorter X-structures. An increase of both parameters changes the morphology of in-plane bars and X-structures. In some cases we observed even double X-structures. The main effect of the bulge is to prevent buckling at intermediate and late stages of the disc evolution. Comparison of models with different halo masses indicates that the smallest observable values of opening angles can be associated with the presence of a heavy dark halo (more than 3 masses of the disc within the optical radius)., Comment: 19 pages, 36 figures, accepted for publication in MNRAS

UV irradiation of materials consisting of a polymer matrix that possesses precursors of different kinds can result in creation of nanoparticles within the irradiated domains. Such photoinduced nanocomposites are promising for photonic applications due to the strong alteration of their optical properties compared to initial non-irradiated materials. We report our results on the synthesis and investigation of plasmonic, excitonic and exciton-plasmonic photoinduced nanocomposites. Plasmonic nanocomposites contain metal nanoparticles of noble metals with a pronounced plasmon resonance. Excitonic nanocomposites possess semiconductor nanoclusters (quantum dots). We consider the CdS–Au pair because the luminescent band of CdS nanoparticles enters the plasmon resonance band of gold nanoparticles. The obtaining of such particles within the same composite materials is promising for the creation of media with exciton–plasmon resonance. We demonstrate that it is possible to choose appropriate precursor species to obtain the initially transparent poly(methyl methacrylate) (PMMA) films containing both types of these molecules either separately or together. Proper irradiation of these materials by a light-emitting diode operating at the wavelength of 365 nm provides material alteration demonstrating light-induced optical absorption and photoluminescent properties typical for the corresponding nanoparticles. Thus, an exciton-plasmonic photoinduced nanocomposite is obtained. It is important that here we use the precursors that are different from those usually employed.

Evolution of the UV-induced absorption within the polymer matrix possessing a highly soluble CdS precursor is studied. The initially optically transparent (polymethylmethacrylate based) samples are irradiated by a light-emitting diode operated at 365 nm for different intensities and different temperatures. In situ monitoring of the process is performed at a wavelength of 405 nm where the samples are initially transparent. The study shows that the increase in absorbance is temperature dependent, and at a fixed temperature it is determined by UV exposure rather than the intensity or irradiation time separately. TEM, HR TEM data, as well as data on absorption and luminescent spectra, allow the relation of the optical absorption evolution to the CdS nanoparticles growth process. This provides new valuable information on the kinetics of this phenomenon in UV irradiated polymer films with a soluble precursor.

Thiophenecarboxylic acid and its derivatives were synthesized by the reaction of thiophenes with the CCl4-CH3OH-catalyst system in total yields of 44-85%. The probable scheme of the reaction involves successive oxidation of methanol with tetrachloromethane to methyl hypochlorite and formaldehyde. Under the action of the latter, thiophene undergoes oxymethylation, giving rise to 2-oxymethylthiophene, which is oxidized with CH3OCl to 2- thiophenecarboxylic acid. In the presence of an excess of CH3OH, the latter is subjected to esterification. It was found that Fe(acac)3, VO(acac)2, and Mo(CO)6 are the catalysts of choice for this reaction.

We demonstrate that [Cd(N(SCNEt2)2)2] is a CdS-containing compound that is well dissolved in a PMMA (polymethylmethacrylate) matrix. The PMMA films possessing up to 10% of these molecules are visually transparent and have no evidence of light scattering. Irradiation of these films by Light Emitting Diodes (LED) operated at a wavelength of 365 nm provides a permanent material alteration with the optical properties of the modified domains (absorption band, luminescent spectra) that are typical for the solid solution of CdS nanoclusters. We show that here the LED radiation is a more effective tool than both the forth and the third harmonics of a Nd:YAG laser and that both photochemical and light heating effects are significant for the above material processing.