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Novikova L.,Voronezh State Academy of Forestry and Technologies | Roessner F.,Carl von Ossietzky University | Belchinskaya L.,Voronezh State Academy of Forestry and Technologies | AlSawalha M.,Jubail Industrial College | Krupskaya V.,RAS Institute of Geology and Mineralogy
Applied Clay Science | Year: 2014

Surface acid-base properties of natural clays and non-clay minerals from Jordanian (J) and Russian (R) deposits as well as H-ZSM-5 were studied applying catalytic reaction of 2-methylbut-3-yn-2-ol (MBOH) conversion. Products of both acidic and basic pathways of the reaction were formed involving surface acid/basic sites of clay minerals. Specific conversions of MBOH decreased in the following order: kaolinite-R>hydromica-R>bentonite-J>red-kaolinite-J=palygorskite-R=H-ZSM-5>zeolite-J>white-kaolinite-J>diatomite-J, which fairly correlated with TPD-NH3 acidity assessment for a majority of samples. However, a contribution of basic sites to the reaction should be taken into account, especially for hydromica-R and kaolinite-R.The strength of acid sites of natural aluminosilicates was compared based on surface acidity and reaction product yields. After 116. min of MBOH conversion, the strength of acid sites changed in the following order: kaolinite-R. >. palygorskite-R. >. bentonite-J. >. red- kaolinite-J. >. white-kaolinite-J. >. zeolite-J. >. diatomite-J. >. H-ZSM-5. At an early (17. min) stage of the reaction, the strength of active sites for natural zeolite-J and H-ZSM-5 were comparable, while the latter underwent significant deactivation due to its microporous structure.The rise of activation temperature from 500. °C to 700. °C for montmorillonite containing sample increased the conversion of MBOH due to the formation of stronger or additional number of basic sites as a result of mineral dehydroxylation. Natural clay samples with a higher content of montmorillonite (30-80%) altered the acid-base properties of the surface and observed higher ability to convert MBOH over acid and basic pathways. © 2014 Elsevier B.V.

Rogazinsksya O.V.,Voronezh State University | Sidorkin A.S.,Voronezh State University | Milovidova S.D.,Voronezh State University | Naberezhnov A.A.,RAS Ioffe Physical - Technical Institute | And 3 more authors.
Bulletin of the Russian Academy of Sciences: Physics | Year: 2011

The dielectric nonlinearity and pyroeffect in matrix composite based on porous glass with inclu-sions of sodium nitrite are investigated. It is found that the composite polarization turns to zero at a temper-ature below that of the phase transition in the bulk NaNO2. The obtained dependence of the pyrocoefficient on temperature also corroborates the existence of the phase transition in sodium nitrite nanoparticles included in the porous matrix. © Allerton Press, Inc., 2011.

Ivanova O.A.,Voronezh State University | Korotkikh N.I.,Voronezh State Academy of Forestry and Technologies | Matveev N.N.,Voronezh State Academy of Forestry and Technologies | Gitlin V.R.,Voronezh State University
Bulletin of the Russian Academy of Sciences: Physics | Year: 2011

The results from investigating vinylpyrrolidone polymerization in aqueous solutions with different concentrations of monomer in aliphatic alcohols, aromatic hydrocarbon, and ester under the action of ion- izing radiation with a quantum energy of 1.2 MeV and pulsed magnetic fields with a maximum magnetic induction value of 0.8 T and action frequency equal to 50 impulses per second are presented. The influence of γ irradiation and magnetic fields on polyethylene oxide crystallization processes is investigated. A mathe- matical model that consistently describes the influence of magnetic fields on the amplification of the gel for- mation process in polyvinylpyrrolidone and on the suppression of polyethylene oxide crystallization from the melt is proposed. © Allerton Press, Inc., 2011.

Safonov A.,Voronezh State Academy of Forestry and Technologies | Sedliacik J.,Technical University In Zvolen | Zotova E.,Voronezh State Academy of Forestry and Technologies
Acta Facultatis Xylologiae | Year: 2014

The goal was to create a mathematical apparatus for process control of wood pellets production. Techniques of expert assessment and planning active industrial experiment were applied. Output objective functions of the process of biofuel production in the form of pellets are obtained. Plan of active industrial experiments was developed. It has taken into account the specific features of the used industrial equipment, technical specification and properties of raw materials. Objective information about the output technical and economic parameters of the process was get. Parameters, objectively changing according to the laws of probability in real rather wide ranges, were considered. The resulting equations of energy intensity changes and mechanical strength of the pellets, the temperature of the matrix, the performance of the used equipment, production costs were quite adequate to the real process. The average error is 0.562% for the entire series of experiments for all of the above-mentioned objective functions. These equations make it possible to carry out single-criterion and multi-criteria optimization to enhance the effectiveness of the production process of pellets and analysis in industrial environment. It makes possible to optimize the possible modes and create mathematical apparatus for automatic control systems. © 2014, Technical University in Zvolen. All Rights reserved.

Kadyrmetov A.M.,Voronezh State Academy of Forestry and Technologies | Kashapov N.F.,Kazan Federal University | Sharifullin S.N.,Kazan Federal University | Saifutdinov A.I.,Kazan Federal University | Fadeev S.A.,Kazan Federal University
IOP Conference Series: Materials Science and Engineering | Year: 2016

The article presents the results of experimental studies of the quality of cleaning steel surfaces by a glow discharge for plasma spraying. Shows the results of measurements of the angle of surface wetting and bond strength of the plasma coating to the surface treated. The dependence of the influence of the glow discharge power, chamber pressure, distance between the electrodes and the processing time of the surface on cleaning efficiency. Optimal fields of factors is found. It is shown increase joint strength coating and base by 30-80% as a result of cleaning the substrate surface by a glow discharge plasma spraying.

Matveev N.N.,Voronezh State Academy of Forestry and Technologies | Farberovich O.,Tel Aviv University | Kamalova N.S.,Voronezh State Academy of Forestry and Technologies | Evsikova N.Y.,Voronezh State Academy of Forestry and Technologies
Physics of the Solid State | Year: 2015

One of the possible methods of increasing the pyroelectric coefficient in order to enhance the volt-watt sensitivity of polymer films has been considered. The sensitivity of the relative variation in the volt-watt sensitivity of a thin polymer film in an inhomogeneous temperature field has been estimated. © 2015, Pleiades Publishing, Ltd.

Novikova L.,Voronezh State Academy of Forestry and Technologies | Belchinskaya L.,Voronezh State Academy of Forestry and Technologies | Roessner F.,Carl von Ossietzky University | Alsawalha M.,Jubail Industrial College
Acta Geodynamica et Geomaterialia | Year: 2013

Catalytic test reaction of methylbutynol (MBOH) conversion was applied to investigation of natural clays and non-clay minerals from Jordanian (bentonite, kaolinite, diatomite, zeolite) and Russian (palygorskite, kaolinite, hydromica) deposits as well as H-ZSM-5. Palygorskite and kaolinite containing samples have shown the highest catalytic activity. Conversion over Jordanian clay minerals decreased in the order: zeolite > bentonite > red kaolinite > white kaolinite > diatomite that agreed to change of acidity, surface area of samples. Sufficient deactivation was observed for H-ZSM-5, kaolinite and hydromica due to adsorption of secondary product in micropores of raw minerals. Products of both acidic and basic pathways of test reaction were formed indicating the presence of acid and basic sites on clays surface, apart from acidic catalyst H-ZSM-5. The yield ratio of acidic to basic products was above the unity for zeolite, bentonite, red kaolinite, and palygorskite; equal to unity for diatomite and hydromica, and less then unity for white kaolinite. It was observed for kaolinite containing sample that high activation temperature increased conversion of MBOH owing to formation of additional basic sites as a result of mineral dehydroxylation. Rise of montmorillonite content from 30 to 80 % provided 91-97 % of MBOH conversion.

Morkovina S.S.,Voronezh State Academy of Forestry and Technologies
Life Science Journal | Year: 2014

In this article we study the theoretical-methodological approach to provision of development of small and medium-sized entrepreneurship in the system of forestry management. The instruments of stating the forms of state and entrepreneurship cooperation and organization of entrepreneurial activity in forestry management of sparsely wooded region were suggested. The principles of differentiation of woodlots of sparsely wooded regions in conditions of provision of balance of interests of wood resources owner and forest users-enterprises owners were also provided. We have also suggested the algorithm, which allows defining the predisposition of the region (forestry district, group of forestry districts) to developing certain forms of entrepreneurship.

Alsawalha M.,Jubail Industrial College | Roessner F.,Carl von Ossietzky University | Novikova L.,Voronezh State Academy of Forestry and Technologies | Bel'chinskaya L.,Voronezh State Academy of Forestry and Technologies
World Academy of Science, Engineering and Technology | Year: 2011

The acidity of different raw Jordanian clays containing zeolite, bentonite, red and white kaolinite and diatomite was characterized by means of temperature programmed desorption (TPD) of ammonia, conversion of 2-methyl-3-butyn-2-ol (MBOH), FTIR and BET-measurements. FTIR spectra proved presence of silanol and bridged hydroxyls on the clay surface. The number of acidic sites was calculated from experimental TPD-profiles. We observed the decrease of surface acidity correlates with the decrease of Si/Al ratio except for diatomite. On the TPD-plot for zeolite two maxima were registered due to different strength of surface acidic sites. Values of MBOH conversion, product yields and selectivity were calculated for the catalysis on Jordanian clays. We obtained that all clay samples are able to convert MBOH into a major product which is 3-methyl-3-buten-1-yne (MBYNE) catalyzed by acid surface sites with the selectivity close to 70%. There was found a correlation between MBOH conversion and acidity of clays determined by TPD-NH 3, i.e. the higher the acidity the higher the conversion of MBOH. However, diatomite provided the lowest conversion of MBOH as result of poor polarization of silanol groups. Comparison of surface areas and conversions revealed the highest density of active sites for red kaolinite and the lowest for zeolite and diatomite.

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