bluuebunny/crossref_metadata_2025 huggingface dataset:
Theoretical research on excited-state intramolecular proton coupled charge transfer modulated by molecular structure
Authors: Yang Dapeng , Yang Guang , Jia Min , Song Xiaoyan , Zhang Qiaoli , Zhang Tianjie , Gao Haiyan
Published: August 2018

Charge transfer from O1 to O2 of 3HFN results in proton H1 transfer from O1 to O2 in S1 state, while small energy barrier facilitates proton H1 transfer from O1 to N1 in S1 state of diCN-HBO, which results in charge transfer from O1 to di-cyano.
High yield accelerated reactions in nonvolatile microthin films: chemical derivatization for analysis of single-cell intracellular fluid
Authors: Wei Zhenwei , Zhang Xiaochao , Wang Jinyu , Zhang Sichun , Zhang Xinrong , Cooks R. Graham
Published: August 2018

The identification of trace components from an individual cell can require derivatization under mild conditions for successful analysis by mass spectrometry (MS).
A stable metal cluster-metalloporphyrin MOF with high capacity for cationic dye removal
Authors: Wang Zheng , Zhang Jian-Hua , Jiang Ji-Jun , Wang Hai-Ping , Wei Zhang-Wen , Zhu Xunjin , Pan Mei , Su Cheng-Yong
Published: August 2018

A super stable anionic MOF was built from Cu5-cluster and Cu-porphyrin to exhibit 2D-HOF/3D-MOF interpenetrated topology, showing high adsorption capacity for cationic dyes.
Potentiation of the ibuprofen antihyperalgesic effect using inorganically functionalized diatomite
Authors: Janićijević Jelena , Milić Jela , Čalija Bojan , Micov Ana , Stepanović-Petrović Radica , Tomić Maja , Daković Aleksandra , Dobričić Vladimir , Nedić Vasiljević Bojana , Krajišnik Danina
Published: August 2018

Refined diatomite from the Kolubara coal basin (Serbia) was inorganically functionalized through a simple, one-pot, non-time-consuming procedure.
Polymers and hydrogels for local nucleic acid delivery
Authors: Fliervoet Lies A. L. , Engbersen Johan F. J. , Schiffelers Raymond M. , Hennink Wim E. , Vermonden Tina
Published: August 2018

This review focusses on the rational design of materials (from polymers to hydrogel materials) to achieve successful local delivery of therapeutic nucleic acids.
Novel patterning of flexible and transparent Ag nanowire electrodes using oxygen plasma treatment
Authors: Kim Hoijoon , Lee Giseok , Becker Stefan , Kim Ji-Seon , Kim Hyoungsub , Hwang Byungil
Published: August 2018

We explore a novel patterning method for flexible and transparent Ag nanowire electrodes using oxygen plasma treatment without a toxic etchant and its application to source/drain electrodes of MoS2-based thin-film transistors.
Strong reverse saturable absorption effect of a nonaggregated phthalocyanine-grafted MA–VA polymer
Authors: Chen Jun , Xu Yong , Cao Mihong , Wang Yafei , Liang Tongxiang , Li Hui , Wang Shuangqing , Yang Guoqiang
Published: August 2018

The amino-substituted phthalocyanines (TA-PcInCl) with high optical limiting effect are grafted onto the copolymer matrix of maleic anhydride (MA) and vinyl acetate (VA), to obtain a novel phthalocyanine grafted polymer (MA–VA-PcInCl) with superior nonlinear absorption effect.
A self-healing and stretchable light-emitting device
Authors: Shi Xiang , Zhou Xufeng , Zhang Ye , Xu Xiaojie , Zhang Zhitao , Liu Peng , Zuo Yong , Peng Huisheng
Published: August 2018

A self-healing and stretchable electroluminescent device is developed from an electroluminescent phosphor sandwiched between two aligned carbon nanotube/polyurethane composite electrodes.
Axial oxygen vacancy-regulated microwave absorption in micron-sized tetragonal BaTiO3 particles
Authors: Baek Kyungnae , Lee Seung-Yong , Doh Sang-Gil , Kim Miyoung , Hyun Jerome K.
Published: August 2018

Microwave absorption of micron-sized BaTiO3 particle composites are enhanced up to −26 dB by effective control over ferroelectric domain wall motion mediated by axial oxygen vacancies.
Switchable single fluorescent polymeric nanoparticles for stable white-light generation
Authors: Wang Hong , Zhang Peisheng , Krishnan Baiju P. , Yu Maolin , Liu Jie , Xue Mingju , Chen Shu , Zeng Rongjin , Cui Jiaxi , Chen Jian
Published: August 2018

We describe SFPNs that can alternate luminescence between stable white-light and cyan- or pink-light emission upon photoirradiation or solvent-induced swelling.
The Effects of Syntactic Complexity and Sentence Length on the Speech Motor Control of School-Age Children Who Stutter
Authors: Usler Evan R. , Walsh Bridget
Published: August 2018

Purpose

Early childhood stuttering is associated with atypical speech motor development. Compared with children who do not stutter (CWNS), the speech motor systems of school-age children who stutter (CWS) may also be particularly susceptible to breakdown under increased processing demands. The effects of increased syntactic complexity and sentence length on articulatory coordination were investigated.

Method

Kinematic, temporal, and behavioral indices of articulatory coordination were quantified for school-age CWS (
n
= 19) and CWNS (
n
= 18). Participants produced 4 sentences varying in syntactic complexity (simple declarative/complex declarative with a relative clause) and sentence length (short/long). Lip aperture variability (LAVar) served as a kinematic measure of interarticulatory consistency over repeated productions. Articulation rate (syllables per second) was also calculated as a related temporal measure. Finally, we computed accuracy and stuttering frequency percentages for each sentence to assess task performance.

Results

Increased sentence length, but not syntactic complexity, increased LAVar in both groups. This effect was disproportionately greater for CWS compared with CWNS. No group differences were observed for articulation rate. CWS were also less accurate in their sentence productions than fluent peers and exhibited more instances of stuttering when processing demands associated with length and syntactic complexity increases.

Conclusions

The speech motor systems of school-age CWS appear to be particularly vulnerable to processing demands associated with increased sentence length, as evidenced by increased LAVar. Increasing the length and complexity of the sentence stimuli also resulted in reduced production accuracy and increased stuttering frequency. We discuss these findings within a motor control framework of speech production.
ICI suppressing scheme in OFDM systems over multipath fading channels
Authors: Ma Tianming
Published: August 2018

A novel scheme with the method of subcarrier modulation is proposed. Comparing with the other existing self‐cancellation methods, the proposed scheme not only has the advantages of good inter‐carrier interference (ICI) suppression capability and high bandwidth efficiency, but also shows a better bit error rate performance over multipath fading channels.
Achievement of frequency‐controlled wide‐angle beam scanning antenna with metasurface at 0.3 THz
Authors: Zheng Shen , Li Chao , Zhang Xiaojuan , Fang Guangyou
Published: August 2018

In this Letter, a frequency‐controlled wide‐angle beam scanning antenna operating at 0.3 THz was proposed based on metasurface. The antenna formed by H‐shape cells is periodical, and its’ scanning property is analysed by the Floquet theorem. To widen the scanning angular scope, higher order mode's diffraction wave was proposed. A systematic method was developed for the design of a practical frequency‐controlled beam scanning antenna in THz band, in which the optimisation of scanning range, linearity and the avoidance of beam blocking are comprehensively considered. Additionally, a coherent enhancement mechanism for improving the mode competition efficiency of the high‐order diffraction mode was implemented. The proposed antenna and optimisation method was verified by the measured wide‐angle beam scanning at the frequency band 0.25–0.3 THz, the measured beam scanning range of the main lobe covers from −41.7° to −25.5° with a good linearity, which is much wider than that of the first‐order mode. The diffraction efficiency of the main lobe measured is 74% on average, which indicates the remarkable inhibition of the unwanted diffraction.
High‐resolution SAR imaging from azimuth periodically gapped raw data via generalised orthogonal matching pursuit
Authors: Qian Yulei , Zhu Daiyin
Published: August 2018

Occurrence of periodical gapping in synthetic aperture radar (SAR) raw data poses a challenge in obtaining focused images. Traditional SAR imaging algorithms fail to process the periodically gapped raw data. A method is proposed to solve this problem. The presented method consists of phase compensation and recovering raw data in range Doppler domain via generalised orthogonal matching pursuit. Then, the recovered raw data is capable of being processed with the traditional SAR imaging algorithms. The Omega‐K algorithm is selected to focus the reconstructed raw data. The presented method is validated on performing better in comparison with the spectral method periodically gapped amplitude and phase estimation by point target simulation and analysis. In simulation, the raw data loses 50% by the form of azimuth periodical gapping. The resolution of point targets can reach 0.25 m in both azimuth and range direction. In addition, real SAR raw data is utilised to verify the effectiveness of the proposed method.
Design of a miniaturised broadband 3 × 3 mm antenna for intraocular retinal prosthesis application
Authors: Kaim Vikrant , Kanaujia Binod K. , Rambabu Karumudi
Published: August 2018

A highly compact and broadband antenna suitable for a prosthetic device to restore vision in the blind is presented. By embedding three straight sections of meandered microstrip patch line at the feed point, the proposed antenna gives three separate bands at 2.45, 4.2, and 5.8 GHz. The square patch loop is etched in the centre for miniaturisation. Three U‐shaped patch stubs are utilised for frequency tuning. Three bands are merged together by adopting two square annular rings in the ground to obtain a wider bandwidth (2–8 GHz) incorporating unlicensed industrial, scientific and medical (ISM) and UWB bands.
Pre‐emphasis enabled 50 Gbit/s transmission over 1000 m SMF using a 1060 nm single‐mode VCSEL
Authors: Lengyel T. , Simpanen E. , Gustavsson J.S. , Larsson A. , Karlsson M. , Andrekson P.A. , Sorin W.V. , Mathai S. , Tan M.R. , Bickham S.
Published: August 2018

A single‐mode 1060 nm vertical‐cavity surface‐emitting laser (VCSEL) and single‐mode fibre (SMF) based link with two‐tap active pre‐emphasis enabling error‐free transmission of 50 Gbit/s NRZ‐OOK over 1000 m is presented.
Protection in DC microgrids: a comparative review
Authors: Bayati Navid , Hajizadeh Amin , Soltani Mohsen
Published: August 2018

A direct current (DC) microgrid has become a superior power system in recent years due to the development of DC loads and higher efficiency of DC systems. One of the challenging problems on DC microgrids operation is protection, and it is still a particular concern associated with the challenges of developing a proper protection scheme owing to its characteristics and lack of standards in DC protection. Due to the significant increasing interest on DC microgrid; this study investigates protection problems and schemes that need to be addressed in modern power systems involving DC microgrids. This study analyses and presents a comprehensive review of the most recent growth in the DC microgrids protection. Additionally, the fault characteristics of DC microgrids, the impact of constant power loads, the protection devices and several proposed methods to overcome the protection problems are discussed. The differences between the proposed protection methods for the DC microgrids are also discussed.
A global correlation linking young stars, clouds, and galaxies
Authors: Mendigutía I. , Lada C. J. , Oudmaijer R. D.
Published: August 2018

Context. The star formation rate (SFR) linearly correlates with the amount of dense gas mass (Mdg) involved in the formation of stars both for distant galaxies and clouds in our Galaxy. Similarly, the mass accretion rate (Ṁacc) and the disk mass (Mdisk) of young, Class II stars are also linearly correlated.

Aims. We aim to explore the conditions under which the previous relations could be unified.

Methods. Observational values of SFR, Mdg, Ṁacc, and Mdisk for a representative sample of galaxies, star forming clouds, and young stars have been compiled from the literature. Data were plotted together in order to analyze how the rate of gas transformed into stars and the mass of dense gas directly involved in this transformation relate to each other over vastly different physical systems.

Results. A statistically significant correlation is found spanning ~16 orders of magnitude in each axis, but with large scatter. This probably represents one of the widest ranges of any empirical correlation known, encompassing galaxies that are several kiloparsec in size, parsec-size star-forming clouds within our Galaxy, down to young, pre-main sequence stars with astronomical unit-size protoplanetary disks. Assuming that this global correlation has an underlying physical reason, we propose a bottom-up hypothesis suggesting that a relation between Ṁacc and the total circumstellar mass surrounding Class 0/I sources (Mcs; disk + envelope) drives the correlation in clouds that host protostars and galaxies that host clouds. This hypothesis is consistent with the fact that the SFRs derived for clouds over a timescale of 2 Myr can be roughly recovered from the sum of instantaneous accretion rates of the protostars embedded within them, implying that galactic SFRs averaged over ~10–100 Myr should be constant over this period too. Moreover, the sum of the circumstellar masses directly participating in the formation of the protostellar population in a cloud likely represents a non-negligible fraction of the dense gas mass within the cloud.

Conclusions. If the fraction of gas directly participating in the formation of stars is ~1–35% of the dense gas mass associated with star-forming clouds and galaxies, then the global correlation for all scales has a near unity slope and an intercept consistent with the (proto-)stellar accretion timescale, Mcs/ Ṁacc. Therefore, an additional critical test of our hypothesis is that the Ṁacc−Mdisk correlation for Class II stars should also be observed between Ṁacc and Mcs for Class 0/I sources with similar slope and intercept.
Outstanding X-ray emission from the stellar radio pulsar CU Virginis
Authors: Robrade J. , Oskinova L. M. , Schmitt J. H. M. M. , Leto P. , Trigilio C.
Published: August 2018

Context. Among the intermediate-mass magnetic chemically peculiar (MCP) stars, CU Vir is one of the most intriguing objects. Its 100% circularly polarized beams of radio emission sweep the Earth as the star rotates, thereby making this strongly magnetic star the prototype of a class of nondegenerate stellar radio pulsars. While CU Vir is well studied in radio, its high-energy properties are not known. Yet, X-ray emission is expected from stellar magnetospheres and confined stellar winds.

Aims. Using X-ray data we aim to test CU Vir for intrinsic X-ray emission and investigate mechanisms responsible for its generation.

Methods. We present X-ray observations performed with XMM-Newton and Chandra and study obtained X-ray images, light curves, and spectra. Basic X-ray properties are derived from spectral modelling and are compared with model predictions. In this context we investigate potential thermal and nonthermal X-ray emission scenarios.

Results. We detect an X-ray source at the position of CU Vir. With LX ≍ 3×1028 erg s−1 it is moderately X-ray bright, but the spectrum is extremely hard compared to other Ap stars. Spectral modelling requires multi-component models with predominant hot plasma at temperatures of about TX = 25 MK or, alternatively, a nonthermal spectral component. Both types of model provide a virtually equivalent description of the X-ray spectra. The Chandra observation was performed six years later than those by XMM-Newton, yet the source has similar X-ray flux and spectrum, suggesting a steady and persistent X-ray emission. This is further confirmed by the X-ray light curves that show only mild X-ray variability.

Conclusions. CU Vir is also an exceptional star at X-ray energies. To explain its full X-ray properties, a generating mechanism beyond standard explanations, like the presence of a low-mass companion or magnetically confined wind-shocks, is required. Magnetospheric activity might be present or, as proposed for fast-rotating strongly magnetic Bp stars, the X-ray emission of CU Vir is predominantly auroral in nature.
Seed and biological productivity of Prunella vulgaris L. in situ and ex situ
Authors: Barsukova Irina , Astashenkov Alexei
Published: August 2018

Reproductive biology and biological productivity of Prunella vulgaris L. were studied in natural growth conditions in Khakasiya and under introduction. It was established that in the wild a potential seed productivity of the species varied from 85,4 to 160,3 it./ a shoot, a real one – from 73,6 to 149,2 it.; erem germination under optimal conditions reached 90,5%. Under introduction the indicators of seed productivity increase by 2-5 times, of erem germination – by 1,5 times. Biological productivity of individuals in cultivation is by 5-10 times higher compared to that in natural habitats.
Seed productivity and dynamics of germination of Ziziphora L. species in the Pamir-Alay
Authors: Bobokalonov Kobil , Cheryomushkina Vera
Published: August 2018

Seed productivity of 4 Ziziphora species: Z. pamiroalaica, Z. interrupta, Z. brevicalyx, and Z. suffruticosa growing in the Pamir-Alay Mountains was stUdied. It was revealed that the indicator of real seed productivity did not exceed 40 %. Seed viability and character of germination were studied. It was established that seeds of all species did not have a dormancy period, had high viability, up to 95 % and high germination energy.
Spatial structure of the Kodar-Kalar orobiome botanical diversity on bioclimatic basis
Authors: Bocharnikov Maxim V. , Stas’ko Anton A.
Published: August 2018

Bioclimatic substantiation of the vegetation spatial structure of the Kodar-Kalar orobiome on the basis of altitudinal vegetation divisions using the global climate model (BioClim) was carried out. Statistical analysis showed differences between altitudinal belts, sub-belts and also larch forests types on average annual temperature and average annual precipitation. The possibility of using the climate as a factor of differentiation of the vegetation cover at the regional level has been proved.
Plant characteristics determination in sand pits near Moscow
Authors: Dabbagh Alaa
Published: August 2018

Sand pits are man-made landforms, where vegetation selfrestoration becomes very difficult. An in-depth study of sand pits’ flora and vegetation must be done in order to restore the complete canopy on sand substrate, which prevents the movement of slopes. In Zvenigorod and Dzerzhinsk sand pits, aged about 70 years, we have studied the slopes with northern and southern exposure for 3 years. The article shows that all the 131 species which we have found in the surveyed area were species of vascular plants. Projective cover degree made up 20-30% which, in general, is a typical characteristic of sandy terrain. Hemicryptophytes dominate the spectrum of life forms by K. Raunkiaer in our research. According to the classification of life forms by I. G. Serebryakov, sand slopes are dominated by herbaceous perennial polycarpics, among which long and short rhizome plants and tap rooted plants are in majority. A significant proportion of tap rooted plants is due to their high degree of adaptation to strong light conditions and resistance to drought. Long-and short rhizome plants tend to loose substrates and soft soils.
New locations of rare lichen species in the Krasnoyarsk region
Authors: Eromasova Natalya , Zyryanova Olga
Published: August 2018

As a result of lichenological studies of the Salbinka River valley, new locations of lichen species listed in the Red Data Books of the Russian Federation and the Krasnoyarsk Territory have been identified. New habitats of Usnea longissima Ach., Lobaria isidiophora Yoshim., Lobaria scrobiculata (Scop.) P. Gaertn. and Lobaria pulmonaria (L.) Hoffm. have been revealed. Their brief characteristics in the studied habitats are given and the state of thalli is described.
Phylogenetic relationships betweenChondrillaL. species in European Russia based on plastid DNA sequencing
Authors: Kashin Alexandr , Schanzer Ivan , Kritskaya Tatyana , ParkhomenkO Alena
Published: August 2018

The article examines the genetic diversity in 54 populations of 9Chondrillaspecies (C. acantholepis,C. ambigua,C. brevirostris,C. canescens,C. graminea,C. juncea,C. laticoronata,C. latifolia, andC. pauciflora) in European Russia. Plastid DNA segments trnT–trnF are selected as markers. Reconstruction of evolutionary networks based on the principle of maximum parsimony reveals that the sample is divided into four groups, where group 1 isC. ambigua, 2 –C. brevirostris, 3 –C. laticoronata, 4 –C. acantholepis,C. canescens,C. graminea,C. juncea, andC. latifolia. The findings show thatC. acantholepis,C. canescens,C. graminea,C. junceaandC. latifoliaare to be treated as synonyms under the name ofC. juncea.
Genome composition and assessment of the divergence between Russian boreal species in the genus Elymus (Poaceae) detected on the basis of sequencing of the nuclear gene GBSSI
Authors: Kobozeva Elena , Asbaganov Sergey , Agafonov Alexander
Published: August 2018

A comparative study of the sequence of GBSSI gene fragments in 10 species of the genus Elymus growing in the territory of Asian Russia was carried out. Data on the genomic composition and on the levels of interspecific divergence were obtained. This information is a necessary requirement for the construction of phylogenetically oriented taxonomic system of the genus Elymus within Russia.
Assessment of genetic fidelity of Fritillaria dagana (Liliaceae) regenerated plants using	ISSR markers
Authors: Muraseva Dinara S. , Kobozeva Elena V. , Novikova Tatyana I.
Published: August 2018

ISSR analysis of Fritillaria dagana, endangered ornamental geophyte from the Sayan Mountains, regenerated through direct gemmogenesis from bulb scale tissue was performed. More informative electrophoresis profile with clear and distinct bands was obtained at amplification with (CAC)3GC primer at 56 °C annealing. The genetic fidelity of F.dagana regenerants to maternal plants was confirmed.
Cone quality and seed efficiency in the clones from mutational witches brooms ofPinus sibirica
Authors: Polyakova Olga , Zhuk Evgeniya , Goroshkevich Sergei
Published: August 2018

Mutational witches' broom is a fragment of the tree crown with abnormal morphogenesis including slow shoot growth, abundant branching and decreased apical dominance which caused by somatic mutation that presumably originates in the apical meristem bud. To study the variability in the cone quality and seed efficiency in witches' broom clones ofPinus sibirica, the cone size and structure were assessed in 21 mutant clones. The mutant clones were significantly differentiated both by the cone traits and seed quality. Their cone size varied from less than 3 to 4 cm. The clones had large number of sterile scales in proximal and distal cone parts, and from 16 to 39 fertile scales per cone. Cones from all mutant clones were inferior to average normal cones of the species. Six clones had large portion of filled seeds, more than 70%, and the other clones had less than 50% of filled seeds. The clones had 10-33% of empty seeds and 1-73% of seeds with collapsed megagametophyte per cone. In general, the seed quality in mutants was quite low, but individual clones had almost normal seed quality, and their seed efficiency was within the species norm.
Biogeocenosis development during initial revegetation of a coal combustion ash dump
Authors: Sheremet Natalia , Belanov Ivan , Doronkin Vladimir , Lamanova Tatiana , Naumova Natalia
Published: August 2018

The initial stage of biogeocenoses development on the coal ash dump produced by the thermal power staton in Novosibirsk (55.000, 83.068), Russia, were studied after 9 years of spontaneous revegetation. Soil properties, soil cover and plant communities were examined in detail. The predominating types of embryozems and transition from open to succession plant communities were described. Soil substrate moisture content was found to determine changes in plant species composition, projective cover and abundance, altogether causing asynchronicity of soil formation in different sites.
Ontogenetic structure of Thymus L. (Lamiaceae) coenopopulations in Yakutia
Authors: Talovskaya Evgeniya
Published: August 2018

Ontogenetic structure of coenopopulations of four model species Thymus extremus, T. indigirkensis, T. brevipetiolatus and T. pavlovii widely distributed in Yakutia was studied. It was established that species coenopopulations were normal, most of them incomplete. Dependence of the type of the ontogenetic spectrum of coenopopulations on growth conditions and ontogenesis pattern was revealed in thymes of different biomorphs. The bimodal type of the ontogenetic spectrum (monocentric dwarf subshrub T. extremus) is conditioned by irregular seed regeneration and lack of ripe and old generative stages. Formation of the left-side type of the ontogenetic spectrum is governed by the emergence of vegetative propagation of individuals (unobvious polycentric dwarf subshrub T. brevipetiolatus and dwarf semishrub T. indigirkensis) and substrate features (distinct polycentric dwarf semishrub T. pavlovii).
Crown structure of 25-year-old Siberian stone pine grafts from mother trees of different ages
Authors: Velisevich Svetlana , Popov Alexander , Goroshkevich Sergei
Published: August 2018

Inheritance of the age-specific traits of the Siberian stone pine crown structure by vegetative progeny was analyzed. Studies were carried out on 25-year-old grafts onto the same species seedlings as rootstocks. Scions for grafting were sampled from two groups of trees: young-mature (YM) and old growth (OG) trees in the southeast of the West Siberian Plain. The analysis of graft development showed that the YM trees had a significantly higher and thicker trunk, and their crowns were broader and denser due to a larger number of shoots. They multiplied by means of the branching feature due to the predominance of axes 2-3 branching orders. The OG trees formed small and transparent crowns that visually resembled separate branches from the upper parts of the crown of ontogenetically old trees. It was suggested that in the vegetative progeny of trees of a different ontogenetic state, the growth potential was epigenetically inherited.
Antiviral activity of fungi of the Novosibirsk Region: Pleurotus ostreatus and P. pulmonarius (Review)
Authors: Vlasenko Vyacheslav , Vlasenko Anastasia
Published: August 2018

The article reviews of antiviral properties of two species of fungi from the Novosibirsk Region of the genus Pleurotus. Fruit bodies and cultivated mycelium of Pleurotus ostreatus and P. pulmonarius are a promising source of extracts with polysaccharides, possessing antiviral and anti-cancer properties.
Variation of nuclear DNA content in seeds of Nitraria schoberi L.
Authors: Voronkova Maria , Banaev Evgeniy , Tomoshevich Maria , Ak-Lama Taigana
Published: August 2018

For the first time are search of nuclear DNA relative content in Nitraria schoberi L. seeds from 15 natural populations of Siberia, the Crimea, Kazakhstan, and Tajikistan has been conducted by the method of flow cytometry. High intra-and interpopulational variations of nuclear DNA content - 2,93-3,39 pg, at average value - 3,22±0,108 pg is revealed.
Analyses of asiatic hybrids resistance at introduction in northern forest steppe of west Siberia
Authors: Vronskaya Oksana , Mosiahina Natalia
Published: August 2018

The contents of main pigments of photosynthetic apparatus (chlorophyll a, b and carotinoid) in the leaves of Asiatic hybrids varieties during different stage of vegetation was first determined In conditions of northern forest steppe. It was established that 19 varieties of Asiatic hybrids had maximum level of accumulation of chlorophyll pigments (a and b) during the budding period, 4 – during the flowering period, 2 – during the fructification period; the most important value a/b was proper to 8 varieties in the budding period, 6 – in the fructification period and 11 in the flowering period, the maximum accumulation of carotinoind contained in the budding period that was expressed in the adaptive reaction of plants aimed to increase of photosynthetic apparatus resistance during the most dry season period. Analyses of photosynthetic pigment contents in the leaves of Asiatic hybrids varieties showed that the flowing changes in the contents of pigment complex may be considered as indicators of a mechanism of adaptation of lily varieties to the complex of climatic and natural conditions of northern forest steppe of West Siberia.
Isomer composition of tocopherols in seabuckthorn (Hippophae rhamnoides L.) seeds in forest-steppe area of Altai territory
Authors: Zemtsova Anna , Zubarev Yury
Published: August 2018

Estimation of tocopherol isomers composition in seed oil of seabuckthorn (H. rhamnoides ssp. mongolica) varieties is represented. It has been established that α-tocopherol is the dominant tocopherol in the lipids of the seabuckthorn seeds, the mean content of which for two years has been ranged from 2.1 (Dar Katuni) to 4.8 mg/100 g (Yantarnaya). In general within the evaluated group of subspecies, the mean content of α- tocopherol was determined at 3.5±0.3 mg/100 g. β-, γ- and δ-tocopherols were characterized by low content, accumulating an average for two years at 0.5±0.1, 1.3±0.1 and 0.7±0.3 mg/100 g, respectively.
Icing control model and algorithm for wasteheat exchangers of ventilation systems
Authors: Arbatskiy Аndrew , Garyaev Аndrew , Glasov Vasiliy
Published: August 2018

Currently, ice control on various heat exchangers to be used for waste heat recovery of discharge air is a rather topical subject because ice building is a factor to reduce efficiency of heat recovery. In such systems, icing always takes place on the side of humid discharge air, with a background of heat exchange between inlet air at temperatures of -30°C and below, and discharge air. To effectively prevent this, it is required to find solutions to problems as follows: study a mechanism of ice building on heat exchange surfaces when interacting with humid air; determine engineering methods to prevent icing, for each type of heat-exchange apparatus, and check efficiency of their operation; develop a mathematical model of ice growth on heat exchange surfaces to enable to vary key parameters (both geometrical and algorithmical ones), determined beforehand, and engineering means aimed at icing prevention.
Numerical simulation of non-isothermal absorption in a liquid film moving over a cooled horizontal surface under the action of a gas flow
Authors: Bartashevich Maria V.
Published: August 2018

Mathematical model of absorption on a horizontal film of lithium bromide water solution flowing on a cooled wall under the action of shear stress is numerically investigated in this paper. The shear stress on the film surface is set by the motion of co-current or counter-current surrounding saturated water vapor flow. It is known that the external shear stress is caused by the motion of surrounding saturated water vapor intensificate the process of non-isothermal absorption in comparison with the fixed-vapor regime. Our calculations have shown that at low values of heat flux the film temperature and vapor concentration in the solution downstream increases due to absorption.
Mathematical modeling of processes of heat and mass transfer during drying of wood biomass
Authors: Ivanova Natalya , Bulba Elena
Published: August 2018

For the first time, a mathematical model for the drying of woody biomass during conductive heating with localization of the evaporation front has been formulated. The processes of moisture removal during the filtration of steam through the porous structure of the material at an ambient temperature of Te = 373 K were considered. Humidity was varied (in the range from 6% to 40%) and dimensions of wood blanks (Rd = 0.0035 - 0.035 m). Based on the results of numerical simulation, the conditions and characteristics (evaporation rate Wisp, drying time τ dry) of the process of moisture removal from wood biomass are determined. The mathematical model allows to calculate the drying time, as well as the mass evaporation rate for different sizes of wood sample, humidity and temperature conditions.
Determination of heat-mass transfer coefficients within the apparatuses with jet-film contact devices
Authors: Madyshev Ilnur N. , Dmitrieva Oksana S. , Dmitriev Andrey V.
Published: August 2018

One of the ways of intensifying the heat and mass transfer processes in gas-fluid systems is designing jet-film contact devices with a developed surface of phase contact at high flow velocities. A contact jet-film device has been developed. The results of numerical investigation of the operation of this device are presented. There were determined the coefficients of heat transfer to the air from the surface of liquid inside of the drain cup of contact device. The criterion equations of convective heat transfer for engineering calculations of jet-film contact devices is corrected.
Combustion of mixtures containing the activated aluminium powder
Authors: Dubkova Yana , Mostovchikov Andrei , Kuznetsov Valery
Published: August 2018

The ballistic characteristics of the mixture compositions containing aluminum powder ASD-6M have been studied. It is shown that the activation of aluminum powder by microwave radiation leads to an increase in the combustion heat of the mixture composition by 11%.
Experimental investigation of the process of hydrate-formation by the method of explosive boiling of liquefied freon 134a in the water volume during decompression
Authors: Meleshkin Anton V. , Elistratov Dmitriy S.
Published: August 2018

The experiments on obtaining gas hydrate of refrigerant 134a were carried out by the method, based on explosive boiling-up of a layer of liquefied gas in a bulk of water at decompression. It is shown that this method combines several factors, leading to intensification of hydrate formation process, resulting in the fast gas hydrate growth. The effect of the decompression rate on the volume of produced hydrate was studied experimentally.
Numerical Investigation of Tungsten Reduction Process
Authors: Gicheva Natalia , Shvab Alexander , Brendakov Vladimir
Published: August 2018

The subject of this research was a chemical reactor for the producing tungsten coverings by means of chemical vapor deposition. The physical and mathematical model of viscous incompressible fluid motion and heat and mass transfer in a vortex chamber has been described. The velocity field, the temperature and the concentration distributions in a vortex chamber were obtained. Calculations reliability was verified by different methods. Parametric studies on effects of the Reynolds, Prandtl and Rossbi criteria on the flow characteristics were performed.
Ordinary differential equations for the dynamic characteristics of heating boilers
Authors: Khaustov Sergei , Guk Olga , Razov Igor
Published: August 2018

The paper presents ordinary differential equations for the dynamic characteristics of a solid fuel boiler that can be combined into one-dimensional nonstationary mathematical model for simulating long-term dynamics of a solid fuel boiler. This model requires less computational time for a qualitative simulation of boiler’s operation than known CFD-solutions. The long-term dynamic model presented can help to determine annual costs, to set up automatic control systems and to detect dangerous deviations in the project.
Levitation of liquid microdroplets over a dry heated substrate near triple-phase contact line
Authors: Kirichenko Dmitry , Zaitsev Dmitry , Kabov Oleg
Published: August 2018

Levitating droplets of liquid condensate are known to organize themselves into ordered arrays over hot liquid-gas interfaces. We report experimental observation of similar behaviour over a dry heated substrate in the vicinity of the triple-phase contact line with high local evaporation rate. It was found that there is an area near the contact line, where no levitating droplets are observed. The width of this area increases with the substrate temperature. Also, it was found that the distance between adjacent levitating droplets increases with the temperature.
Study of in-furnace gas-dynamic processes with different design of vortex burners
Authors: Koksharev Oleg M. , Gil Andrey V.
Published: August 2018

The paper considers the combustion chamber of the boiler unit designed for burning Ekibastuz coal by vortex burners with opposed wall firing. Since Ekibastuz coal is not highly reactive, and also has a high content of the mineral part, then vortex burners are used for its combustion. The use of standard two-channel burners leads to increased generation of nitrogen oxides, therefore, in this article the combustion processes of burning Ekibastuz coal using multi-channel burners are considered. The studies were carried out using numerical methods.
The effect of the liquid layer thickness on the evaporation intensity
Authors: Kreta Aleksei , Maksimov Vyacheslav
Published: August 2018

An experimental study of the influence of thermo-capillary forces and shear stresses with the side of the gas flow to the evaporation flow rate has been made. The experiments were carried out at various thicknesses of the liquid layer and constant gas velocity. The influence of the thickness of the liquid layer on the evaporation flow rate (the intensity of evaporation) has been analyzed. It is shown that the thermocapillary forces have a direct effect on the evaporation flow rate of the liquid layer.
Calculation of temperature distribution and effective temperature in high burnup fuel of WWER-1000
Authors: Kudrov Alexander , Kuzmin Arian , Savitsky Denis
Published: August 2018

The problem of finding an effective temperature is highly important. This characteristic provides calculation of the power effect reactivity (PER), which defines safe and stable operation of nuclear reactor. The numerical experiment, which is considered on average and maximum heat load conditions, is put to find out changing of the effective temperature in the high burnup fuel of WWER-1000. In the course of the experiment mathematical statement of the problem is made, numerical solution of which is found with using the finite differences approximation of both control equations and border conditions. Also, the method of simple iteration is used for calculating temperature distributions, according to determination of the effective temperature. The linear approximation was obtained basing on effective and maximum temperatures depending on the burnup.
Study of heat transfer processes in the flowing part of hypersonic air-ramjet engine
Authors: Maslov Eugene , Zharova Irina , Faraponov Valery , Kozlov Eugene , Matskevich Vladislav
Published: August 2018

The technique and results of the experimental-theoretical study of gas dynamics, heat transfer and the structure of gas flow in the flowing channel of a model hypersonic air-ramjet engine are presented for Mach numbers M = (5; 6).
Influence of the water level in the work area on the hydrate formation process
Authors: Meleshkin Anton V. , Elistratov Dmitriy S.
Published: August 2018

This article describes a fundamentally new method for obtaining gas hydrates, based on self-organization in a closed working section of the cyclic boiling-condensation process of the gas-hydrate generator. A special feature of this method is the high rate of hydrate formation at low energy costs and, as a consequence, the expected efficiency of new technologies built on its basis over analogues. A series of experiments was performed, which shows the effect of the water level on the work site on the hydrate formation process.
Evaporation of layers of salt solutions
Authors: Misyura S. Y. , Morozov V. S.
Published: August 2018

Nonisothermal evaporation of layers of water and aqueous salts solutions of H2O/LiBr, H2O/CaCl2 and H2O/LiCl was studied experimentally. The liquid layer was placed on a horizontal heated wall. The initial concentration of salt C0 was 10 %. The wall temperature Tw = 75 °C and ambient air pressure was 1 bar. It was shown that the heat flux q increases for water for the final evaporation stage and falls for salt solutions due to the increase in salt concentration C and due to a significant drop in the equilibrium partial pressure of water vapor.
Influence of water-methanol solution additives on hydrocarbon fuel combustion in burner
Authors: Naumkin Aleksandr S. , Borisov Boris V. , Nigay Aleksandr G.
Published: August 2018

Mathematical model of burning disposal a water-methanol solution by the gas fuel is presented. Two-dimensional model in the ANSYS Fluent Software is made. Thermal distribution of the flare and distribution of methane concentration are derived. We analysed the results of mathematical modelling.
Improving the quality of coal is one of the factors in intensification of combustion processes in coal-based energy
Authors: Patrakov Yuriy , Semenova Svetlana , Usanina Anna
Published: August 2018

For flotation enrichment of coals, spent engine oils modified with ozone were used. Preliminary ozonation contributes to the increase in the share of low-boiling components in the compositions of spent oils, also it reduces the viscosity of reagents and improves their flotation properties when coals are enriched. By flotation of coal, using ozonized spent oils, the yield of concentrate significantly increases, ash content is reduced, mineralization of waste flotation is increased, and as a result, the selectivity of the process is increased as well.
Optimization of construction of a shell for launcher in the water medium in the supercavitation regime
Authors: Arkhipov Vladimir , Zolotorev Nikolay , Perfilieva Ksenia
Published: August 2018

New scheme of a shell, providing increase in range and stability of the movement in the water medium due to realization of the supercavitation regime on all trajectory of its movement, has been considered. The results of the analysis in the efficiency of the movement of a shell in the water environment in the supercavitation mode are presented.
The modeling of the dust deposits on the surfaces of cyclone scrubber
Authors: Vasilevsky Michail , Razva Aleksandr , Zaharov Dmitri , Shabirov Danil
Published: August 2018

The phenomena at interaction of agglomerate of disperse material with the surface of the inertial device are considered. It is revealed that tension in the interactions between the agglomerate surface can reach values comparable to atmospheric pressure, which is the reason for the formation of solid deposits, what is the reason of formation of strong deposits which, in turn, are defined by the autohesion communications of particles forming agglomerate.
Thermal regimes of space composite structures. Part II
Authors: Reznik Sergey
Published: August 2018

Composite materials have a unique combination of mechanical and thermal characteristics. This allows you to create lightweight, durable, heat-resistant design. In the article the common features for all space composite structures were highlighted. The article deals with the thermophysical problems arising in the design of space composite structures associated with strict requirements for their weight and functional efficiency. The feasibility of using combined heat transfer models to improve design accuracy has been shown.
An experimental study of the effect of water bodies temperature on water heat pump performance
Authors: Saloum Amer , Maksimov Vyacheslav I.
Published: August 2018

The purpose of this research is to study the effect of water temperature change in the reservoir on water heat pump performance. An experimental analyse is done on the heat pump station which depends on water as a heat source. The experimental results confirm that the ice formation has a negative effect on the heat exchange efficiency, and the increase in water source temperature slow down the ice formation rate which causes an appositive effect on the system performance.
Analysis of the effect of water steam concentration on water drop cooling process efficiency in conditions of water cooling towers of thermal power plants
Authors: Shevelev Sergei
Published: August 2018

Numerical investigation of transient distribution of temperature in water drops cooled in cool blast in conditions typical for high capacity evaporative water cooling towers has been done. Water drops cooling through thermal conductivity and water evaporation has been taken into consideration. It has been proved that the analysis of temperature distribution along the radius of water drop increases reliability of evaluation results of average temperature of water drops when they are cooled. Effect of water steam concentration in steam-gas mixture layer surrounding a water drop on water cooling towers efficiency has been evaluated.
Dynamics of dry spots in the liquid film moved by the gas flow in the mini-channel under intensive local heating
Authors: Tkachenko Egor
Published: August 2018

Experimental studies of hydrodynamics and the heat transfer crisis were carried out for a two-phase stratified flow in a mini-channel with intensive heating from a heat source of 1x1 cm2. It has been established that as the heat flow increases, the total area of dry spots on the heater increases, but when a certain temperature of the heater surface reaches ≈100 °C, the area of dry spots begins to decrease. With the help of high-speed visualization (shooting speed 100000 frames per second), several stages of formation of a dry spot (a typical size of the order of 100 microns) were isolated. It was found that at a heat flux of 450 W/cm2 about 1 million dry spots per 1 second are formed and washed on the surface of the heater (1 cm2). The speed of the contact line when dry spot is forming reaches 10 m/s.
Determination of thermophysical and thermokinetic characteristics of forest combustible materials
Authors: Zhdanova Alena , Kralinova Svetlana , Nyashina Galina
Published: August 2018

The danger of forest fires and their large-scale consequences is facing humanity more and more sharply from year to year. We carried out experimental studies to determine the thermal characteristics (thermal conductivity, heat capacity, thermal diffusivity) and thermokinetic characteristics (activation energy, pre-exponential factor) of typical forest combustible materials and their mixtures for a wide range of temperatures (298–423 K). A generalization of experiments for typical forest combustible materials of the Far Eastern Federal District of Russia was performed. The established experimental values can be used for mathematical modeling of occurrence, propagation and extinguishing of forest fires.