Efimova, E. V.

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XVII Международная научно-практическая конференция имени профессора Л.П. Кулёва504studyinG the behaVior of ti-o-n CoatinGs of Coronary stents in tissue fluidsE.V. EfimovaScientific supervisor – PhD, Associate Professor, L.A. Leonova Linguistic advisor – Senior lecturer, Ya.V. ErmakovaNational Research Tomsk Polytechnic University Russia Tomsk, Lenin Avenue, 30, office 127, eve7@tpu.ruCurrently, coronary stenting is one of the most effective methods of myocardial revascularization, that is restoration of blood supply to a particular area of the heart muscle. There are several genera-tions of stents: stents using pure metal, stents with a polymer coating, with a drug coating, bioresorb-able stents. One of the most effective technologies of stent surface modification is to apply a coating of titanium oxynitride. TiON coating reduces platelet adhesion and fibrinogen binding compared to the stent material (stainless steel) [1]. Also because of to the electrochemical effect of the protective coat-ing, the tendency to corrosion of implants in body fluids (blood, lymph, interstitial fluid) decreases significantly.The object of our study are biocompatible TiON films deposited by reactive magnetron sputtering on the experimental installation "UVN-200MI" (TPU, Tomsk) [2]. A substrate for the application of unilat-eral coatings – Crystal KBr.Purpose – to study the behavior of Ti-O-N coat-ings in the tissue fluids: dissolution / chemical and physical durability.For studies, as a model biological fluid physio-logical solution NaCl (0.9%) was used. The solvent volume of NaCl (4 мл) was determined according to the area of the sample (2 cm2) according to the recommendations of GOST R ISO 10993-12-2009 [3]. Test samples of TiON coatings were kept for 30 days in NaCl (0.9%). Further samples were removed; the solution was filtered using "blue tape", and analyzed to detect el-ements of the covering. For these purposes, we used atomic-emission analysis (AEA) – a method for de-termining the elemental composition of substances by optical emission line spectra of atoms and ions of the sample excited in light sources. The choice fell on this method of analysis, as compared with other optical spectroscopic and many chemical and physico-chemical methods of analysis it is possible to contactlessly, rapidly determine a large number of elements over a wide concentration range with acceptable accuracy using a small sample mass. The analysis was performed on a device of atomic-emission spectrometer ICAP 6300 Duo. As standard, reference solutions, state standard sam-ples MES-1 and MES-2 were used. AEA results are shown in Table 1. It is evident that with decreasing concentrations of an element in a series of samples of the same composition, the intensity of the spectral lines of the element in the corresponding spectra is reduced on the condition that the excitation parameters are held constant and spectra are recorded [4]. Since the spectral lines belonging to a particular element have different intensity, by decreasing its concen-tration weaker lines will disappear in the spectrum before the more intense ones. As a result, according to the absence of some lines in the spectra and the presence of other more intense lines of the given element, one may conclude about its concentration in the sample.The experimental data have identified the pres-ence of ions in solution of such elements as Na, K, Ti. A large number of Na is due to the use of NaCI as solvent. The minimum amount of Ti confirms chemical resistance of oxynitride coating TiNOX.table 1. Results of the AEA-analysis of the sample af-ter 30 daysmeasuring the numberThe concentration of elements in the test solution, mg/lNa К Ti1 119600 44.53 0.00052 120500 44.22 0.0006average value120000 44.38 0.0005 Секция 7.  Химия и химическая технология на иностранном языке505references1. Tsyganov I.A., Pozdnyakova A.I., Richter E. Meits M.F. Development of hemocompatible titanium-based coatings by plasma-immersion plasma implantation and metal deposition.// Bulletin of Lobachevsky State University of Nizhny Novgorod, Novgorod Bulletin, 2007.– 1.– 214.2. Konishchev M.E., Kuzmin O.S., Pustovalova A.A. etc. Structure and properties of coatings based on Ti-O-N, formed by reactive magnetron sputtering // Proceedings of the universities. Physics, 2013.– Vol.56.– №10.– P.35–40.3. GOST R ISO 10993-12-2009. Medical devices. Biological evaluation of medical devices. Sam-ple preparation and reference samples // Stand-artinform.– M., 2010.– 2.– 16.4. Khasanov R.R., Khusainov R.R. Atomic emis-sion spectral analysis: Study guide.– Kazan: Kazan (Volga) Federal University, 2012.– P.27.the study of Coal-water slurry on the basis of brown Coal with the addition of nano-siZed Carbon GlobulesT.Y. Emelyanova, L.V. Kashkina, O.P. StebelevaScientific supervisor – PhD, Associate professor, V.E. Redkin Linguistic advisor – PhD, Associate professor, E.N. BelovaSiberian Federal University 660041, Russia, Krasnoyarsk, 79 Svobodny pr., Emelyanovatatiana.sfu@mail.ruThe basis of coal-water fuel studed in this work is a highly concentrated (50 wt. %) slurry (CWS). The dispersed phase is finely-powdered Kansk-Achinsk coal, the dispersion medium is dis-tilled water. The novelty of the investigation lies in the fact that low concentrations (0.04, 0.08, 2 wt. %) of nanoglobular carbon (carbon black T-900) were added instead of amphiphilic surface-active agents (surfactants), which are injected in CWS in order to regulate its physico-chemical, structural-mechani-cal (rheological) properties.The form of coal particles is developed or bluff, the size – 50 mkm … 3.8 mkm (bimodal distribu-tion). The shape of the particles of carbon black is streamlined, the globules. The average size is about 160 microns (initial) but less than 100 nm in CWS (Figure 1). Carbon black grade is selected by the efficiency of its absorption of polyurethane. [1]The curves of dynamic viscosity (viscometer Reotest-2) are similar to a non-Newtonian fluid’s curves (Figure 3). They are approximated by pow-fig. 1.  Shape of dispersed particles of CWS: a – carbon powder, b – carbon particles, c – carbon globulesba cfig. 2.  Polyurethane sample after the impregnation of the carbonaceous slurry

Studying the behavior of Ti-O-N coatings of coronary stents in tissue fluids

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