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Kharkiv, Ukraine

Yavetskiy R.P.,Institute for Single Crystals of NAS of Ukraine | Kosyanov D.Yu.,Institute for Single Crystals of NAS of Ukraine | Baumer V.N.,State Scientific Institution | Doroshenko A.G.,Institute for Single Crystals of NAS of Ukraine | And 4 more authors.
Journal of Rare Earths

The fabrication peculiarities of low-agglomerated yttria (Y 2O3) nanopowders via thermal decomposition of sulfate-doped precursor with transient morphology were studied. It was determined that Y2(OH)5(NO3) x(CO2)y(SO4)z· nH2O (n=1-2) crystalline precursor underwent fragmentation and decomposition into isolated quasi-spherical Y2O3 particles upon calcination. Effect was connected with minimizing the free energy of the plate-like crystallites via reducing the contact surface until to the moment of spheroidization and attainment of isolation that occurred at T=1100 °C. Residual sulfate ions slowed down the surface diffusion during heat treatment thus retaining quasy-spherical morphology and low aggregation degree of Y 2O3 nanopowders. Sulfate-doped yttria nanopowders with medium particle size of 53±13 nm possessed improved sinterability in comparison with undoped ones arising from finer particle size, narrower particle distribution and lower agglomeration degree. © 2014 The Chinese Society of Rare Earths. Source

Ilyuschenko A.,State Scientific Institution | McCartney G.,University of Nottingham | Zhang D.,University of Nottingham | Yellup J.,University of Nottingham
Welding and Cutting

Ferrites are iron-containing, ceramics which exhibit magnetic properties. They are non-conducting and therefore employed in high frequency applications. Most ferrites possess a spinel crystal structure and one of the most common is (Ni,Zn)1 Fe2O4. Bulk ferrites are typically made by conventional ceramic powder processing. However, manufacture of thick coatings is of growing interest and deposition by thermal spraying is potentially attractive. This paper reports work on the development of (Ni,Zn)1 Fe 2O4 based powder feedstock of specific composition and coating deposition by both air plasma (APS) and high velocity oxy-fuel (HVOF) spraying. Powders and coatings were analysed by X-ray diffraction, optical and scanning electron microscopy so that phases present, microstructure and phase composition could be investigated. The influence of process parameters on coating development was studied for both APS and HVOF sprayed deposits. Particular attention was paid to degradation of the spinel crystal structure, the formation of iron oxide phases and elemental loss during spraying. The results obtained show that a degree of decomposition of the ferrite material occurred with the loss of zinc and formation of wustite (FeO). The Zn loss is very dependent on the surface-tovolume ratio of the powder used in spray deposition and this is a more important factor than particle temperature or residence time in a high temperature environment. Source

Sukhodolya S.,Vinnitsa National Medical University | Falalyeyeva T.,Taras Shevchenko National University | Kuryk O.,State Scientific Institution | Petrushenko V.,Vinnitsa National Medical University | Beregova T.,Taras Shevchenko National University
Current Issues in Pharmacy and Medical Sciences

The search for new prophylactic and therapeutic drugs for the treatment of chronic pancreatitis (CP) is an urgent problem in current pancreatology. A promising direction in CP therapy may be the use of nonsteroidal anti-inflammatory drugs. Hence, the aim of the present study was to investigate the selective inhibition properties of COX-2 rofecoxib on the development of pancreas fibrosis in rats with experimental chronic pancreatitis induced by Dibutyltin dichloride (DBTC). The 60 male albino Wistar rats of our study were placed into three groups of 20 animals in each: I - the intact control; II - that which received an intraperitoneal injection (i.p.) of DBTC (6 mg/g); III - those which, 28 days after administration of DBTC (6 mg/g, i.p.), received a two-week course of treatment of rofecoxib (5 mg/kg, i.p). One day after rofecoxib treatment was completed, analysis was undertaken regarding the level of amylase, as well as the pancreatic amylase and lipase in the blood serum and the prostaglandin E2 in the pancreatic tissue. In addition, the morphological condition of the pancreas was ascertained. The obtained data suggest that administration of Rofecoxib reduces the development of fibrosis and improves the morpho-functional state of the pancreas in rats with chronic pancreatitis induced by DBTC. Thus, treatment with a selective COX-2 inhibitor could be a possible strategy for improving the clinical outcome of patients with CP. © 2015 Medical University of Lublin. All rights reserved. Source

Ivanov R.V.,State Scientific Institution | Permyakova P.F.,State Scientific Institution | Ilyin A.N.,State Scientific Institution
Biosciences Biotechnology Research Asia

Inclusion of feed additives in the winter diet of pregnant mares increases the consumption of crude protein on 3-21%, for digestible 4-32%. In the summer experience, when grazing on alas and valley meadows Yakut mares consume an average of 330 g per day of crude protein per day on 100 kg live weight 211 g of digestible protein. This is according to 5 experiments. In winter, the consumption of crude protein was at 209 g per day per 100 kg live weight on digestible protein, 136 g for an average of four experiments with data on natural herbage of winter pasture. During summer, the horses' body is intense accumulation of reserve elements, increasing fatness, first by increasing muscle mass, further due to the deposition of subcutaneous fat and visceral fat in the abdomen. At this time in our experiments mare consumed 330 g per day on 100 kg live weight. Source

Sakhno Y.I.,State Scientific Institution | Shishkina S.V.,State Scientific Institution | Shishkin O.V.,State Scientific Institution | Musatov V.I.,State Scientific Institution | And 3 more authors.
Molecular Diversity

Heterocyclization reactions of pyruvic acids, aromatic aldehydes and 5-amino-N-aryl-1H-pyrazole-4-carboxamides yielding four different types of final compounds are described. The reactions involving arylidenpyruvic acids lead with high degree of selectivity to either 4,7-dihydropyrazolo[1,5-a]pyrimidine- 5-carboxylic acids or 5-[(2-oxo-2,5-dihydrofuran-3-yl)amino]-1H-pyrazoles, depending on the catalyst type or temperature regime. The interactions based on arylpyruvic acids can take place under kinetic or thermodynamic control producing 7-hydroxy-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine-7-carboxylic acids or 3-hydroxy-1-(1H-pyrazol-5-yl)-1,5-dihydro-2H-pyrrol-2-ones, respectively. © 2010 Springer Science+Business Media B.V. Source

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