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Competitiveness is one of the most important factors in our life and it plays a key role in the efficiency both of organizations and societies. The more scientifically supported and prepared organizations develop more competitive materials with better physical, chemical and biological properties and the leading companies apply more competitive equipment and technology processes.

The aims of the 2nd International Conference on Competitive Materials and Technology Processes (ic-cmtp2) are the following:

• Promote new methods and results of scientific research in the fields of material, biological, environmental and technology sciences;

• Change information between the theoretical and applied sciences as well as technical and technological implantations.

• Promote the communication between the scientist of different nations, countries and continents.

Among the major fields of interest are materials with extreme physical, chemical, biological, medical, thermal, mechanical properties and dynamic strength; including their crystalline and nano-structures, phase transformations as well as methods of their technological processes, tests and measurements. Multidisciplinary applications of materials science and technological problems encountered in sectors like ceramics, glasses, thin films, aerospace, automotive and marine industry, electronics, energy, construction materials, medicine, biosciences and environmental sciences are of particular interest.

In accordance to the program of the conference ic-cmtp2, more than 250 inquiries and registrations from different organizations were received. Researchers from 36 countries in Asia, Europe, Africa, North and South America arrived at the venue of conference. Including co-authors, the research work of more than 500 scientists are presented in this volume.

Professor Dr Gömze A LászlóChair, ic-cmtp2

The PDF also contains lists of the boards, session chairs and sponsors.

All papers published in this volume of IOP Conference Series: Materials Science and Engineering have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

In parallel with the appearance of new dental materials the number of induced allergic diseases increases. Based on this fact more sensitive detection of allergens is major importance. The Fourier-Transform Surface Plasmon Resonance (FT-SPR) is a sensitive, broadly applicable real-time method for analysing thin layers of materials on gold surfaces. FT-SPR measurement is performed at a fixed angel of incident light, and reflectivity is measured over a range of wavelength in the near infrared. In our study the formaldehyde and benzoyl-peroxide were examined as members of the most common dental allergens by FT-SPR spectroscopy. The aim of this work was the investigation of the suitability of this method for the direct detection of these materials. Different concentrations of formaldehyde and benzoyl-peroxide solutions were measured from this purpose. The individual spectra were measured for all of the solutions, and calibration curves were calculated for the materials for the possibility of the determination of an unknown concentration. In addition, series measurements were performed whereby the association and dissociation properties of formaldehyde or benzoyl-peroxide were described. The results of the experiments proved that the method capable to measure directly these materials and can provide appropriate calibration curves for determination of unknown concentrations.

Many types of polymers are often used in dentistry, which may cause allergic reaction, mainly methyl methacrylate allergy due to the leachable, degradable components of polymerized dental products. The aim of this study was to investigate the interaction between the leachable components of PMMA and peptides by Fourier-transform Surface Plasmon Resonance (FT SPR). In our previous work binding of oligopeptides (Ph.D.-7 and Ph.D.-12 Peptide Library Kit) was investigated to PMMA surface by phage display technique. It was found that oligopeptides bounded specifically to PMMA surface. The most common amino acids were leucine and proline inside the amino acids sequences of DNA of phages. The binding of haptens, as formaldehyde and methacrylic acid, to frequent amino acids was to investigate on the modified gold SPR chip. Self assembled monolayer (SAM) modified the surface of gold chip and ensured the specific binding between the haptens and amino acids. It was found that amino acids bounded to modified SPR gold and the haptens bounded to amino acids by creating multilayer on the chip surface. By the application of phage display and SPR modern bioanalytical methods the interaction between allergens and peptides can be investigated.

In this work, the crystallization process of lithium disilicate glass-ceramic was investigated with SiO₂ from rice husk silica replacing the high-purity SiO₂ starting powder form commercial source. Glasses were developed at the stoichiometric composition of 66%.molSiO₂:33%.molLiO₂ using commercial SiO₂ and the one obtained by thermochemical treatment of rice husk. To compare the SiO₂ sources, the influence of the one from rice husk on crystallization process was measured using different granulometry, analyzing microstructure and the kinetic behavior. Investigations were carried out by means of differential thermal analysis (DTA), X-ray diffractometry (XRD) and scanning electron microscopy (SEM). Amorphous glasses were obtained after melting at 1550°C. The position of lithium disilicate glass-ceramic crystallization peaks (Tp) are between 550 to 660°C to different granulometry (<63mm, 63mm < × < 250mm and 1mm < × < 2mm) and DTA heat rates (5; 10; 15; and 20°C/min) in both glasses, and the relevant formed crystalline phase after DTA analysis (verified for XRD) was Li₂Si₂O₅. SEM images showed the increase of glass substitution for crystalline phase to both glass-ceramics from different silica sources.

It has been studied a porous ceramics obtained from nanocrystalline ZrO₂ powders. Samples were obtained by pressing and sintering of compacts, the porosity of ceramic samples was from 20 to 80%. The average grain size in the studied ceramics increased from 0.4 to 4 microns with increasing sintering temperature and duration of isothermal holding from 1400 to 1600 °C and 1 to 5 hours, respectively. It was shown that the "stress – strain" diagrams on the initial stage of deformation has a nonlinear behavior with high parabolic factor of strain-stress curves. It has been shown that fracture of the materials was observed from the elastic area and has a rod-like and cellular-like parts in its structure.

The effect of sintering process parameters on the properties of 3 mol% yttria partially stability zirconia (3Y-PSZ) ceramics has been investigated. The relative density of the sintered pellet rapidly increases from 70.5 to 93.6% with rose temperature from 1473 to 1573 K. In addition, the relative density only slightly increases from 94.9 to 96.6 %, when rose sintered temperature from 1573 to 1773 K. This result shows that no significant influence on the densification behavior when sintering at 1573 to 1773 K for 2 h. The Vickers hardness and toughness also increase with the sintered temperature.

In recent years, layered double hydroxide (LDH) has been attempted to be applied to a molecular container due to their anion exchange ability, low cytotoxicity and good biocompatibility. In this paper, we investigated the intracellular behaviour of LDH particles in mammalian cells after internalization. Nanoparticles of fluorescein (Fluo) intercalated LDH, Fluo/LDH, were prepared by the coprecipitation followed by subsequent hydrothermal treatment. As-prepared Fluo/LDH particles have the LDH structure and morphology of hexagonal sheet of 100 nm on the average. In addition, Fluo/LDH also exhibited high green fluorescence and low cytotoxicity. By a confocal laser scanning microscopy, the dim green fluorescence was observed throughout cells, including the nucleus. This result indicated that Fluo/LDH released guest anion (Fluo) from LDH structure inside cells. Furthermore, because the fluorescence was observed throughout the cell, Fluo was not retained within endosome structure, i.e., Fluo/LDH was dissolved to release Fluo from endosome.

Calcium phosphate (CaP) bioceramic is well known as bioactive and biocompatible material in bone tissue regeneration applications. Apatitic CaP, especially nano sized hydroxyapatite (NHAp), is more similar to the natural apatite presented in the bone tissue than CaP bioceramics. In the current research NHAp was modified using biodegradable polymer – poly(lactic acid) (PLA) to develop composites providing bone regeneration and local drug delivery. NHAp/PLA microcapsules were prepared using solid-in-water-in-oil-in-water (s/w₁/o/w₂) encapsulation technology. The impact of primary and secondary emulsion stability on the emulsion droplet and microparticle properties was evaluated. The stability of final emulsion can be increased by varying the process parameters. Stable s/w₁/o/w₂ emulsion using 3ml of NHAp suspension, not less than 100ml of 4% PVA water solution and 10ml of 10% PLA solution in dichloromethane can be obtained. S/w₁/o/w₂ microencapuslation method can be effectively used for the preparation of multi-domain microcapsules achieving high NHAp encapsulation efficacy (93%).

A novel hemostatic agent was prepared using phosphoryl oligosaccharides of calcium (POs-Ca), hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂; HAp) obtained by the hydrolysis of POs-Ca or sugar-containing HAp (s-HAp; 60.3 mass% calcium-deficient HAp and 39.5 mass% organic materials, Ca/P ratio = 1.56) and thermoplastic resin (the mixture of random copolymer of ethylene oxide/propylene oxide (EPO) and polyethylene oxide (EO); EPO : EO : water = 25 : 15 : 60 (mass ratio); 25EPO-15EO). The gel formed by mixing 25EPO-15EO with water (25EPO-15EO/water mass ratio: 0.20) was flash frozen at -80°C, freeze-dried at -50°C for 15 h and then ground using mixer. The consistency conditions of hemostats mixed with POs-Ca or s-HAp were optimized for the practical uses. The mean stanching times of hemostats were: s-HAp/25EPO-15EO (8.2 h; s-HAp/25EPO-15EO = 0.20) > 25EPO-15EO (5.3 h) > POs-Ca/25EPO-15EO (4.7 h; POs-Ca/25EPO-15EO = 0.20). The gentamicin, a typical antibiotic agent, loaded s-HAp/25EPO-15EO composite hemostat showed the steady state releasing in phosphate buffered saline till 10 h immersion at 37.0°C.

Solid particles found in an infusion solution under development were examined by scanning electron microscopy combined with X-ray fluorescent elemental analysis. The main fraction of the particles was found to be flakes of corroded glass. The elemental composition of the glass shred surface has proved that the particles originate from the glass matrix, despite the slightly acidic pH of the solution contained. Based on the results, the use of this glass-type as container for this infusion has been rejected.

In this paper some recent material developments will be overviewed mainly from the point of view of automotive industry. In car industry, metal forming is one of the most important manufacturing processes imposing severe restrictions on materials; these are often contradictory requirements, e.g. high strength simultaneously with good formability, etc. Due to these challenges and the ever increasing demand new material classes have been developed; however, the more and more wide application of high strength materials meeting the requirements stated by the mass reduction lead to increasing difficulties concerning the formability which requires significant technological developments as well. In this paper, the recent materials developments will be overviewed from the point of view of the automotive industry.

Centimeter scale AlN sheet has been successfully synthesized by the direct nitridation method with an Al-NH₃–N₂–H₂ system. The starting material is Al sheet with 16-300 micron thickness. Al sheet was gradually transformed into AlN sheet in a tube furnace with NH₃–N₂–H₂ atmosphere at 900–1200°C. Synthesized a large scale AlN sheet has highly crystalline. The size of the AlN sheet with 30×100×0.0016mm has only AlN crystal phase. In microstructure analysis, there are fine AlN particles in an AlN sheet. AlN particle size decreased from 250 to 100 nm with decreasing reaction temperature in the tube furnace. Large scale AlN sheet synthesized at high reaction temperatures have low oxygen contents.

It is possible to obtain cordierite ceramics with high temperature synthesis using both synthetic and raw natural materials. This paper discusses the possibilities to obtain cordierite ceramics, replacing part of required oxides with raw materials from various Latvian deposits of dolomite and clay. The obtained raw cordierite powders were ground in two modes (3 and 12 hours) and fired at 1200 °C. Ceramic samples were characterized by hydrostatic weighting method; crystalline phase composition was studied by XRD. Obtained samples were evaluated by their mechanical (compressive) strength and linear coefficient of thermal expansion (CTE). Thermal shock resistance was tested using water quenching method and afterwards evaluated by using ultrasonic method to test changes in Young's modulus of elasticity. Results show that increase in grinding time causes samples to densify and promote formation of cordierite crystalline phase which corresponds to increase in total compressive strength and decrease of CTE values. CTE values of samples ground for 12 hours conform to that of obtained in other researches.

Due to increased production speeds in modern process environments, the loading conditions in sliding contact applications have become more challenging. Therefore it is important to have good understanding of wear mechanisms in high-speed sliding conditions.

A wear testing device was manufactured for the purpose of cost-efficient simulation of water-containing high-speed sliding conditions. Sliding speeds up to 40 meters per second can be achieved while abrasive-containing slurry is fed into the contact interface of material samples and a rubber coated drum. High-speed wear tests were run with three ceramic materials: silicon nitride, silicon carbide and partially stabilized zirconia. Wear behavior of these ceramics was analyzed as a function of sliding speed and slurry composition.

Results indicate that in mild wear region increase in sliding speed reduced overall wear, whereas in severe wear conditions increasing speed accelerated wear. A transition from mild to severe wear was observed for silicon carbide when tested in alumina-containing slurry. For the materials that had high enough hardness, wear rates were dictated by the respective order of fracture toughness. Visual inspection of the worn samples supported the interpretation of wear mode transition.

Nowadays the most suitable and widely used construction material is concrete. We could develop concrete for every request in connection with the properties of fresh concrete and the quality of hardened concrete, too. The demand is rising in application of special concretes, like high performance and ultra high performance concretes (HPC, UHPC). These are usable in extreme natural circumstances or in very corrosive surroundings (for example: sewage farm, sewer, cooling tower, biogas factories). The pH value of the commercial sewage is between 7–8, but this value is often around 4 or less. The concrete pipes, which transport the sewage, are under corrosion, because above the liquid level sulphuric acid occurs due to microbes. Acidic surroundings could start the corrosion of concrete. When the pH value reduces, the influence of the acids will increase. The most significant influence has the sulphuric acid. The pH value of sulphuric acid is about 1, or less. Earlier in the cooling towers of coal thermal power stations used special coating on the concrete wall. Recently application of high performance concrete without polymeric coating is more general. Cementitious supplementary materials are widely used to protect the concrete from these corrosive surroundings. Usually used cementitious supplementary materials are ground granulated blastfurnace slag (GGBS), flying ash (FA) or silica fume (SF). In the last years there has been a growing interest in the application of metakaolin. Metakaolin is made by heat treatment, calcinations of a natural clay mineral, kaolinite. In our present research the chemical resistance of mortars in different corrosive surroundings (pH=1 sulphuric acid; pH=3 acetic acid) and the chloride ion migration were studied on series of mortar samples using rapid chloride migration test. Cement paste and mortar samples were made with 17% metakaolin replacement or without metakaolin. The following cements were used: CEM II/A-S 42.5 N, CEM I 42.5 N-S. We concluded that the replacement of cement by metakaolin results in significant increases in compressive and tensile strengths and it prevents the infiltration of harmful substances.

The multilayer magnetic circuit for the millimeter scale MEMS (Micro Electrical Mechanical System) air turbine generator is proposed in this paper. The dimensions of the fabricated air turbine generator were 3.6 mm, 3.4 mm and 3.5 mm, length, width and height, respectively. The air turbine was fabricated by the MEMS technology. Multilayer magnetic circuits were fabricated by the green sheet process. The achieved output voltage and output power of the generator were 6.2mV and 1.92μVA respectively. Moreover, the optimization of the ceramic magnetic circuit for the generator was performed to improve the output power. In this experiment, the horseshoe shape circuit and step-wise shape circuit were compared on the output power by the spindle machine. When two kinds magnetic circuit were compared, the output power of the step-wise shape circuit was higher than that of the horseshoe shape circuit. The output voltage and the output power of the step-wise shape circuit were 28mV and 1.53 mVA when load resistance of 0.512 Ω was connected.

Nanocrystalline multilayer thin film coatings, composed of nanometer-scale thick CrN, TiAlN and MoS₂ tri-layer systems, were prepared by reactive co-sputtering processes. The self-lubricated multilayer coating structures were deposited by one-fold oscillating movement of substrates in front of the sputter sources. Three independently operated direct current (dc) excited unbalanced magnetrons (UM) with rectangular cathodes of TiAl alloy (50/50%), pure chromium and MoS₂ were used as sputter sources. The reactive sputtering process was performed in a mixture of Ar-N₂ atmosphere. Hardened high-speed-steel (HSS) and thin oxide covered Si (100) wafers were used as substrates for tribological- and microstructure investigations, respectively. According to results of the chemical composition evaluated by Auger-electron spectroscopy (AES) and microstructure investigation by cross sectional transmission electron microscopy (XTEM), the CrN, TiAlN and the MoS₂ phases form practically continuous layers with large gradient transition of composition. The as-deposited CrN/ (Al,Ti)N/MoS₂ coatings have shown good friction behaviour, tested at room temperature in dry sliding condition with a ball-on-disk tribometer.

Regarding the research and application of ceramic tiles there is a great importance of defining precisely the interaction and friction between surfaces. Measuring slip resistance of floor coverings is a complex problem; slipperiness is always interpreted relatively. In the lack of a consistent and clear EU standard, it is practical to use more method in combination. It is necessary to examine the structure of materials in order to get adequate correlation. That is why measuring techniques of surface roughness, an important contributor to slip resistance and cleaning, is fundamental in the research. By comparing the obtained test results, relationship between individual methods of analysis and values may be determined and based on these information recommendations shall be prepared concerning the selection and application of tiles.

3 at.% Li-doped (Ba_1-xCa_x)(Ti_1-yMn_y)O₃ particles with the Ca²⁺ mole fraction, x, of 0–0.09 and Mn mole fraction, y, of 0 and 0.0005 were synthesized by a solvothermal approach at 200°C. The products consisted of nanoparticles of 50–100 nm in diameter, and did not change very much depending on the amount of Li, Ca and Mn-codoping. The change in relative dielectric constant, Δ_r, in around room temperature decreased by doping Ca²⁺, and the lowest Δ_r (4.51%) could be realized at x value of 0.03. The mechanical quality factor, Q_m, of 3 at.% Li-doped (Ba_0.97Ca_0.03)(Ti_0.9995Mn_0.0005)O₃ increased to 521, and Δ_r decreased to 1.72%, while the piezoelectric constant, d₃₃ (234pC/N), and electromechanical coupling factor, k_p (40.0%), did not change very much compared with 3 at.% Li-doped BaTiO₃.

There are no investigations concerning the microstructural homogeneity in cross section of extruded and sintered samples found in literature. In this work TiO₂ ceramics obtained by extrusion technology is investigated. Samples were sintered under three different sintering conditions: A) 1100→850 °C, B) 1100 °C and C) 1100→1450 °C. Two step sintering at 1100 − 850 °C leads to the formation of denser microstructure (77.2 % of TD) compared to single step sintering at 1100 °C (75.4 % of TD). After thermal treatment there are differences between microstructure in middle and edge part of all samples. Microstructure of samples after each sintering condition is different. Needle-shaped and irregularly shaped grains and bimodal porosity can be found in SEM investigations.

The study of magnesia-chrome refractories corrosion by liquid steel and the liquid calcium-silicate based slag was carried out in the environment in RH degasser. The microstructures of the as-delivered and tested samples were researched by SEM-EDS methods. Our experiment produced the following results: 1. the initial spinel phase, Mg(Cr,Al,Fe)₂O₄ solid-solution of magnesia-chrome brick was transformed into Fe and Mn-rich spinel phase (Mg,Mn)(Cr,Fe)₂O₄ solid-solution, 2. the new phase formed in the corroded brick were (Mn,Mg)O and (Ca,Mg,Mn)SiO₄ solid solutions.

The influence of annealing on the structure and properties of ZO₂ – Y₂O₃ and ZrW₂O₈ powders obtained by the chemical precipitation method is studied. It is shown that the increase in annealing temperature leads to the decrease in the average size of particles, which initially represent porous agglomerates with high specific surface, to the size of monolithic polydomain particles, the sizes of which are comparable with the sizes of crystallites. The grain growth in the ZO₂ – Y₂O₃ system during annealing is defined by surface diffusion. ZrW₂O₈ has a negative thermal expansion and it was equal to −12*10⁻⁶ C⁻¹.

Main component in the lightweight concrete, which provides its properties, is aggregate. A lot of investigations on alkali silica reaction (ASR) between cement and lightweight aggregates have been done with their results published in the academic literature. Whereas expanded glass granules, which is relatively new product in the market of building materials, has not been a frequent research object. Therefore lightweight granules made from waste glass and eight types of cement with different chemical and mineralogical composition were examined in this research. Expanded glass granules used in this research is commercially available material produced by Penostek. Lightweight concrete mixtures were prepared by using commercial chemical additives to improve workability of concrete. The aim of the study is to identify effect of cement composition to the ASR reaction which occurs between expanded glass granules and binder. Expanded glass granules mechanical and physical properties were determined. In addition, properties of fresh and hardened concrete were determined. The ASR test was processed according to RILEM AAR-2 testing recommendation. Tests with scanning electron microscope and microstructural investigations were performed for expanded glass granules and hardened concrete specimens before and after exposing them in alkali solution.

Several types of European and Asian automobile windscreens coated with single and multilayer fixing fluxes and silver thin films were studied, and their material structures and their scratch properties were compared with glass mirrors' by the authors. The realized laboratory tests had shown very strong influences of cracks and bubbles in the microstructures of fixing thin film layers and silver coatings on scratch resistance, acoustic emission and micro-hardness of the coatings both on glass mirrors and automobile windscreens. To examine the material structure of flux thin film layers and silver coatings scanning electron microscopy (SEM) was used. The scratch resistance, acoustic emission, nucleation and propagation of cracks were studied by an optical digital mechanical scratch tester.

The optimum conditions for the fabrication of transparent glass body in the ZnO-B₂O₃ (ZB) and ZnO-B₂O₃-Bi₂O₃ (ZBB) systems were examined by a pressureless firing and subsequent oxygen-supplied hot isostatic pressing (HIP). The pressurelessly-fired opaque ZB glass body possessed the maximum relative density (99.1%) when fired at 620°C for 15 min in air, and was hot isostatically pressed at 630°C for 12 h under the pressure of 150MPa (80%Ar – 20%O₂ atmosphere) to eliminate the residual pores; the light transmittance of this glass body was in the range of 35 to 51% (380 to 800 nm). In order to fabricate the transparent glass body at lower temperature, the fabrication conditions of ZBB glass body were examined. The pressurelessly-fired ZBB glass body possessed a maximum relative density (98.8%) when fired at 500°C for 2 h in O₂ atmosphere and hot isostatically pressed at 490°C for 12 h; the transmittance of the transparent ZBB glass body was in the range of 48 to 58% (500 to 800 nm).

Aluminophosphate glasses belonging to the Li₂O–BaO–Al₂O₃– La₂O₃–P₂O₅ system doped with Tb³⁺ were prepared and investigated. Methods as Induced Coupled Plasma-Mass Spectrometry (ICP-MS), Induced Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) and X-ray diffraction (XRD) have been used to establish the elemental composition of these vitreous materials. The influence of the Tb³⁺ ions on the optical properties of the phosphate glasses has been investigated in relation with the structural characteristics of the vitreous matrix. The optical behavior has been studied by ultra-violet-visible (UV–Vis) spectroscopy, revealing electronic transitions specific for terbium ions. Fluorescence spectroscopy measurements have been performed by excitation in the UV and visible domains (377 nm and 488 nm) which resulted in the most significant fluorescence peaks in the Vis domain (540 and 547 nm). Structural information via vibration modes were provided by Fourier Transform Infrared (FTIR) absorption spectra in the 400–4000 cm⁻¹ range. Absorption peaks specific for the vitreous phosphate matrix were put in evidence as P-O-P symmetrical and asymmetrical stretching vibration modes, P-O-P bend, PO₂- symmetrical and asymmetrical stretching vibration modes, P=O stretching vibration mode as well as P-O-H water absorbance. Raman spectra acquired in the 100–4000 cm⁻¹ range by 488, 514 and 633 nm laser excitation sources disclosed peaks also specific for the phosphate matrix, proving the role of phosphorous oxide as a vitreous network former. Differential Scanning Calorimetry and Thermogravimetric Analysis (DSC-TGA) provided information regarding the phase transformations that took place during the heating process and the associated thermal effects.

The research data related to glass surface treatment and new scattering glass material manufacture by the surface modification with the use of the surface ion exchange are given. The special features of the optical properties of the modified soda lime silica glass with/without the thin Au layer are described and compared with that data related to chemical etched glass. The glass modified by surface ion exchange is characterized by more effective simultaneous light transmission and light scattering and by more strongly pronounced spectral and angular dependences of the scattered light. It was found the noticeably greater (up to 16 times) light intensity at light propagating in the full internal reflection regime. Presented optical data may be useful in the technical and decorative illuminating engineering

Composite-semiconductor and composite-dielectric multilayer films were obtained by the ion beam sputtering method in the argon and hydrogen atmospheres with compositions: {[(Co₄₅-Fe₄₅-Zr₁₀)_x(Al₂O₃)_y]-[α-Si]}₁₂₀, {[(Co₄₅-Ta₄₅-Nb₁₀)_x(SiO₂)_y]-[SiO₂]}₅₆, {[(Co₄₅-Fe₄₅-Zr₁₀)_x(Al₂O₃)_y]-[α-Si:H]}₁₂₀. The images of surface relief and distribution of the dc current on composite layer surface were obtained with using of atomic force microscopy (AFM). The dependencies of specific electric resistance, ferromagnetic resonance (FMR) fields and width of line on metal (magnetic) phase concentration x and nanolayers thickness of multilayer films were obtained. The characteristics of FMR depend on magnetic interaction among magnetic granules in the composite layers and between the layers. These characteristics depend on the thickness of composite and dielectric or semiconductor nanolayers. The dependences of electric microwave losses on the x and alternating field frequency were investigated.

The preparation of CoFe₂O₄ nanoparticles in Igepal CO-520-cyclohexane-water reverse micelle solutions has been studied. Transmission electron microscopy and X-ray diffraction pattern analyses revealed the resultant particles to be CoFe₂O₄. The average size and distribution of synthesized particles calcined at 600⁰C for 2 hrs were in the range of 30 to 70 nm and broaden, respectively. The phase of synthesized particles was crystalline. The magnetic behavior of the synthesized particles was ferromagnetism. The effects of synthesis parameters, such as the molar ratio of water to surfactant and calcination temperature, are discussed.

Iron doped TiO₂ nanoparticles were prepared under the high temperature and pressure conditions by mixture of metal nitrates solution and TiO₂ sol. Fe doped TiO₂ particles were reaction at the temperature range of 170°C–200°C for 6 h. The microstructure and phase of synthesized particles were studied by SEM(FE-SEM), TEM and XRD. Thermal properties of the synthesized particles were investigated by TG-DTA analysis. Also, Specific Surface Area of synthesized particles were studied by BET analysis. X-ray diffraction pattern shows that the synthesized particles shows the coexistence of anatase and rutile reaction at the temperature range of 170°C to 200°C for 6 h. The amount of rutile phase on the synthesized particles increased with decreasing Ag concentration in solution because the less a content of the transposition metal, the easier to phase transition in the same temperature condition. The average size and distribution of the synthesized particles was about 10nm and narrow, respectively. The average size of the synthesized particles increased as reaction temperature increased. Also, BET surface areas of synthesized particles by a hydrothermal process were found to be larger than that of pure TiO₂ which is synthesized by a sol-gel process.

The sophisticated industry and technologies require higher and higher assumptions against mechanical strength and surface hardness of ceramic reinforced metal alloys and metal matrix composites. Applying the well-known alumina powders by dry pressing technology and some special pore-forming additives and sintering technology the authors have successfully developed a new, high porosity alumina matrix material for composites of advenced Al-Mg alloys. The developed new matrix material have higher than 30% porosity, with homogenous porous structure and pore sizes from few nano up to 2–3 mm depending on the alloys containments. Thanks to the used materials and the sintering conditions the authors could decrease the wetting angles less than 90° between the high porosity alumina matrix and the Al-Mg alloys.

Applied analytical methods in this research were laser granulometry, scanning electron microscopy, and X-ray diffraction. Digital image analysis was applied to microscopy results, to enhance the results of transformation.

In the last ten years carbon nanotube composites are in the focus of the researchers. Concentration series were prepared using carbon nanotube containing master blend by IDMX mixer. In the experiments polypropylene, polycarbonate and ABS polymers were used as matrix materials. The prepared materials were characterised by scanning electron microscopy. The carbon nanotubes can be seen on the fractured surfaces. We did not find any sign of agglomerates in the materials. The nanocomposites were investigated by LP-FTIR method. The specimens were irradiated with 1 W for 1 minute by CO₂ laser. The polymer matrix was burnt or charred by the CO₂ laser; the structure of the carbon nanotubes in the matrix was studied. The carbon nanotubes create a physical network in the polymers we used.

For experimental purposes we used a micro-scale ball-cratering tribometer. In case this test, the process parameters (load, angular speed) were constant, the solution of the wear-kinetic differential equation could be expressed in a simple, closed form. It was tested four types of samples according to the next microstructure, low martensitic steel sample (30% martensite and 70% ferrite), medium martensitic steel sample (50% martensite and 50% ferrite), high martensitic steel sample (70% martensite and 30% ferrite), full martensitic steel sample (100% martensite).

On the basis of several years experiments in development of high performance technical ceramics and in investigation of hetero-modulus and hetero-viscous materials and ceramic matrix composites the authors successfully developed a new family of ceramic reinforced lightweight composites with extreme dynamic strength. To obtain these lightweight composites first the matrix materials were developed from different sort of sintered ceramics with high porosity and after the prepared items were re-sintered using reactive sintering methods or were impregnated with nanoparticles of Si₃N₄, SiAlON ceramics or light metal alloys having excellent mechanical strength and properties. Where it was necessary the pores and material structures of ceramic matrix materials anchored excellent wetting for a wide range of metal alloys, so it was possible to develop several types of ceramic reinforced hetero-modulus light metal composites with extreme dynamic strength of different density. In this work the authors present the c-Si₃N₄ diamond particles reinforced corundum matrix composite shield plate structures and some of the specially developed low density ceramic foams and high porosity ceramic matrix materials for lightweight metallic composites.

In recent years it has been indicated by archaeometric investigations that phosphoric-iron (P-iron, low carbon steel with 0,5-1,5wt% P), which is an unknown and unused kind of steel in the modern industry, was widely used in different parts of the world in medieval times. In this study we try to explore the role of phosphorus in the arhaeometallurgy of iron and answer some questions regarding the smelting bog iron ores with high P-content. XRF analyses were performed on bog iron ores collected in Somogy county. Smelting experiments were carried out on bog iron ores using a laboratory model built on the basis of previously conducted reconstructed smelting experiments in copies of excavated furnaces. The effect of technological parameters on P-content of the resulted iron bloom was studied. OM and SEM-EDS analyses were carried out on the extracted iron and slag samples. On the basis of the material analyses it can be stated that P-iron is usually extracted but the P-content is highly affected by technological parameters. Typical microstructures of P-iron and of slag could also be identified. It could also be established that arsenic usually solved in high content in iron as well.

Molecular mechanics studies were performed on structures consisting of Y junctions of carbon nanotubes. Tensile simulations were run on the same structure, wherein atomic force functions of various shape were used. According to the numerical test results the behavior of the structure, the failure site and the failure process could be determined irrespective of the shape of the force function.

Bacteria induced calcium carbonate precipitation nowadays is a widely examined process being a possible alternative for traditional stone conservation methods. While research has been mostly limited to laboratory measurements, application connected, further in situ experiments should be performed in order to evaluate the applicability of the method. In our experiment, several bio-based treating compounds were compared, which have already been analyzed in different laboratories. Method for the treatment was based on the treatment of a French research group, and the compounds were applied on Hungarian porous limestone slabs, in situ. For inoculation bacteria strains Bacillus cereus and Myxococcus xanthus were used, and non-inoculated compounds were also analyzed. After the treatment, specimens were analyzed by means of discoloration effect, water absorption and migration characteristics. Almost all the treating compounds gave favorable or acceptable results for the examined properties, comparing to the properties measured in the non-cured state. Measurements on the chromatic- and on the water absorption aspects gave significant results, while further measurements are running for the more exact evaluation of the migration characteristics, i.e. effective migration depth and wetted volume.

The structure and features of surfaces of clay minerals (kaolin, montmorillonite, etc) have an important scientific and practical value. On the surface the interrelation of processes at electronic, atomic and molecular levels is realized. Availability of mineral surface to external influences opens wide scientific and technical opportunities of use of the surface phenomena, so the research of crystal-chemical and crystal-physical processes in near-surface area of clay minerals is important.

After long term researches of gas-clay mineral system in physical fields the author has obtained experimental and theoretical material contributing to the creation of the surface theory of clays. A part of the researches is dedicated to studying the mechanism of crystal-chemical and crystal-physical processes in near surface area of clay mineral systems, selectivity of the surface centers to interact with gas phase molecules and adsorbophysical properties.

The study of physical and chemical properties of fine clay minerals and their modification has a decisive importance for development of theory and practice of nanotechnologies: they are sorbents, membranes, ceramics and other materials with required electronic features.

Adsorptive filter media were developed based on UHMWPE (ultra high molecular weight polyethylene), perlite mineral and sol-gel synthesized silica gel as support and various cyclodextrin oligomers and polymers as active adsorbents. Adsorptive capacity was characterized by dye adsorption before and after Soxhlet extraction in water to check the hydrolytic stability of the structures obtained. Morphological and in some cases spectroscopic studies were made to understand the differences in behaviour. At the present stage the development of such structures hardly exceeds the trial and error approach, nevertheless some promising formulations were found.

The study of photo catalytic efficiency of leucoxene (Pizhemskoe deposit, Russia) and synthesized on its base rutile and rutile modified with Pt was made. The degradation of trichlorphenol (TCP) under UV irradiation was used as a test reaction. The results showed that specific surface area of leucoxene and as-synthesized rutile is extremely low what predetermines the low photocatalytic activity of these samples. Nevertheless, triclorphenol could be effectively oxidized under UV light when the Pt modified rutile crashed to 13 nm particle size is used as a photocatalyst.

A systematic study aimed at obtaining new organoclays for the treatment of Olive Mill Waste water (OMW) has been performed. Several organoclays have been prepared by loading different amounts of the biocompatible surfactant Tween20 onto the K10 montmorillonite (MMT). Complementary kinetic and equilibrium studies on the adsorption of the Tween20 onto the MMT have been carried out and the characterization of the new tailor-made bio-materials has been performed by means of the XRD and FT-IR measurements. Finally the prepared bio-organoclays have been successfully applied for the OMW remediation and they proved to be highly effective in decreasing the organic content (OC) to an extent that depends on both the amount of loaded surfactant and the experimental protocols applied.

The study of the removal of radionuclides (uranium, radium and thorium) in static conditions from aqueous solutions by analcime-bearing rocks and pure analcime was carried out. The high removal efficiency of all studied radionuclides by analcime-bearing rocks was determined. Analcime was efficient in removing of thorium only.

Deformation and fracture of metal matrix composites under various loading schemes are studied. It is shown that in conditions far from transformation the material is deformed by dislocation glide as an ordinary crystal. In this case, yield stress is inversely proportional to the carbide spacing; in alloys with high solid phase content it is not achieved up lo fracture. Fracture of the material is catastrophically brittle. Deformation tests of composites near the phase transition temperature show that there are different transformations induced by a highly non-uniform stress state of the binding phase. Under loading the transformation scheme B2-> B2+ B19->B2 + "quasi-amorphous state" is realized in the binding phase with the formation of a microcrystalline, highly misoriented structure with the characteristic size of crystallites less than 10 nm. This structure has high plasticity and strong hardening. It governs an efficient transfer of external load to solid particles, inducing dislocation glide even in typically brittle titanium carbide particles. The physical meaning of using binders with unstable structure in composites involves a decrease in the scale of the structural level of plastic deformation due to the formation of the microcrystalline structure of the binding phase during non-uniform loading.

The laboratory technology was developed for the obtaining of nano and submicron powders of II-VIII group metal oxide as well as composites based on mesoporous metal silicates, metal oxides or nanoscale colloidal silver. The optimal parameters of the nanoparticles synthesis: a qualitative and quantitative composition of the reaction mass and thermal treatment mode were determined. The developed approach allows to carry out synthesis of nano sized metal oxide particles with a reference size, to vary it in the range 10–130 nm with an accuracy of 20–30 nm. A distinctive feature of our method is environmental friendliness, efficiency, and simplicity of the technological realization.

Combustion of the metal, magnesium, and aluminum oxides based multicomponent systems in the revolving reactor has been studied. Mullite, corundum, and spinels have been synthesized out-of-furnace by means of the self-propagating high-temperature synthesis. Both the composition and structure of the synthesized ceramic materials have been identified using certain correlation of the initial components and centrifugal acceleration rate. The conditions of synthesizing tubular ceramic materials by combustion of the magnesium – aluminum – aluminum oxide – nickel oxide system have been determined. The tube composition has been represented by corundum and spinel.

Alumina (Al₂O₃) fine particles are widely used as industrial materials including fillers for metal or plastics, paints, polisher, cosmetics and electric substrates, due to its high hardness, chemical stability, and high thermal conductivity. The performance of those industrial products is closely related to the particle size or shape of the alumina particles used, and thus a new synthetic method to control size, shape, and crystal structure of the aluminum oxide is desired for the improvement of the performance. Hydrothermal phase transformation using various aluminum compounds such as oxide, hydroxide, and salt as a staring material, is known as one of the synthetic methods for producing alumina fine particles; however, the influence about the size and shape of the starting aluminum compounds has been little mentioned, although they strongly affect the size and shape of the final products. In this study, we investigated the influence of the shape, size and crystal structure of the starting aluminum compounds on those of the products, and newly succeeded in the production of rod-like α-Al₂O₃ nanoparticles from fibrous boehmite nanoparticles using hydrothermal phase transformation under supercritical water conditions.

The aim of this study was to evaluate the influence of time of ageing on phase evolution of paste from MgO-SiO₂-H₂O phase system. The paste was composed of fine grained sintered magnesia and microsilica in 1:2 molar ratio and water, with water to solid ratio equal 0,5. After preparation the paste was ageing during specified time up to 180 days in temperature 20° C. Phase composition of mixture of MgO and SiO₂ with water was studied by XRD, DTA-TGA. The analysis revealed that product of reaction in mixture of MgO, SiO₂ and water was a probably poorly crystalline magnesium silicate.

The phases trajectories in the fields of primary crystallization of cristobalite (SiO₂^cr), tridymite (SiO₂^tr), mullite (3Al₂O₃-2SiO₂) and in a field of liquid immiscibility are analyzed on a basis of computer model for T-x-y diagram of SiO₂-Al₂O₃-CaO system. The concentration fields with unique set of microconstituents and the fields without individual crystallization schemes and microconstituents are revealed.

Based on positive semidefinite operator properties, an exact ground state solution is deduced for a 2D Hubbard model with periodic boundary conditions on small samples. The obtained ferromagnetic behavior is used as a possible explanation of the ferromagnetism occurring in nano-samples made of non-magnetic but metallic materials.

Special surfaces, corresponding to phase transformation type changing, have been found and designed within six three-phase regions of the system Ti-Ir-Ru with a help of 3D computer model of its T-x-y diagram.

Phase equilibria in Na,K//SO₄,CO₃,HCO₃-H₂O system at 50°C are studied by the translation method. 32 divariant fields, 36 univariant curves, and 13 invariant points are determined in the system. The first closed phase diagram (phase complex) of the investigated quinary system is constructed. The constructed phase diagram is fragmented into divariant fields of co-crystallization of the two phases at the quinary level.

The investigation of the properties of micellar systems is of great practical importance, since the microheterogeneous structure, in particular, of aqueous-organic solutions can be used to create reaction centers with designed properties, which will make it possible to increase the efficiency of processes associated with the intramolecular conversion of the electronic excitation energy of a molecule. In the present paper, model systems to stimulate chemical reactions are the spatial-temporal structures (STS) formed as a result of photophysical and photochemical reactions, whose time characteristics are highly sensitive to a change in the solvent compositions. The STS evolution processes are slow and the structures formed have macroscopic sizes, which makes the system under consideration a convenient object for experimental studies. The spectral and time characteristics of the spatial-temporal structures luminescing when exposed to UV radiation in aqueous alcohol solutions of anthraquinone are investigated experimentally depending on the volume content of alcohol in a mixture. It is shown that the microheterogeneous structure of aqueous alcohol solutions considerably influences the behavior of the dissipative structures formed.

In this work, we evaluate the hierarchical surface topography of reactively sputtered nanocrystalline Pb(Zr,Ti)O₃ and TiO₂ thin films as well as plasma-treated antireflective PET films by means of determining the fractal dimension and power spectral density (PSD) of surface topography recorded by atomic force microscopy (AFM). Local fractal dimension was obtained using the triangulation method. The PSDs of all samples were fitted to the k-correlation model (also called ABC model) valid for a self-affine surface topography. Fractal analysis of AFM images was shown to be an appropriate and easy to use tool for the characterization of hierarchical nanostructures.

Gasket seals are often used in industry and laboratories where a leak-proof installation is needed in order to avoid loss of products or dangerous materials. Many of products transported inside tubes are at relatively high temperatures excluding polymeric gaskets. In the same line, many of transported materials contain solvents which can attack polymer sealings, therefore limiting their use. An alternative is to use graphite joints as sealings. These joints are a sandwich of graphite foil and stainless steel mesh as forming core. The problem that raises using graphite in contact with steel is that at temperatures of about 500 °C an interdiffusion of carbon on the steel structure occurs which produces adhesion of the graphite gasket on the metallic flange. Therefore this adhesion increases the time to change each gasket, since rests of previously adhered graphite has to be removed from the flange. In order to avoid the adhesion of the graphite on the flange, polycarbosilazane precursor was used as protective finishing on the graphite foil surface. After thermal transformation of the polymer into the corresponding PDC finishing, it acts in two manners: It avoids the direct contact between the carbon and the steel and it allows the sealing of liquids and gases. Adhesion tests were done and showed that the foils passivated with PDCs did not adhere to the steel flange. Moreover, the production methods and products are compatible to industrial environment and processes. The results found here show that the time to change the gasket in industry can be clearly reduced by using the PDC finishing on graphite gasket.

The effect of four distinct methods of incorporating fillers into a preceramic polymer matrix was investigated with respect to the structural and mechanical properties of the resulting materials. Investigations were conducted with a polysiloxane/Al₂O₃/ZrO₂ model system used as a precursor for mullite/ZrO₂ composites. A quantitative evaluation of the uniformity of filler distribution was obtained by employing a novel image analysis. While solvent-free mixing led to a heterogeneous distribution of constituents resulting in limited mechanical property values, a strong improvement of material homogeneity and properties was obtained by using solvent-assisted methods. The results demonstrate the importance of the processing route on final characteristics of polymer-derived ceramics.

Polymeric and ceramic coatings with a cellular structure have been manufactured based on demixing processes by the use of two different preceramic polymers and silicon carbide fillers in a dip coating process. The rheological properties of the coating system were adjusted by adding a monomeric silane and methanol, and the crosslinking process was triggered by the addition of catalysts. The surface tension of the coating system was measured and a temperature range for coating and structure formation was identified. The as coated substrates were investigated with respect to an influence of the substrate microstructure and the coating speed on the cellular structure of the coatings. While the substrate microstructure has no influence on the cell structure the coating speed led to a minor change in the cell width. The as received thermoset coatings were pyrolyzed and the structure was intact even after firing at 1100 °C in different atmospheres.

The chemically treatment by alkali solutions of illite clay, so-called geopolymer method, were studied to show the impact on changes of structure and crystalline phases composition of treated not dehydroxylated illite Quarternary clay, as well as ceramic properties and compressive strength of sintered respective ceramic samples. The degree of activating process were followed by FTIR-spectra, X-ray diffraction and differencial thermal analysis. The low temperature ceramic product was achieved by sintering of alkali solution (KOH or NaOH 1M, 3M, 4M and 6M) activated clay samples in temperature range from 100°C to 700°C . Sintered ceramic samples were characterized by compressive strength, total porosity, bulk density and shrinkage.

It is shown that treatment of the illite Quarternary clay by KOH changes illite structure, but not destroyed. Main changes could be connected with changes of O-Al-OH grouping where O is associated with neighbour Si- layer That results into lowering of sintering temperature and development of amorphous (glassy) phase of sintered at 600–700 °C ceramic samples together with growing of total porosity. Consolidated at 600°C ceramic samples have the compressive strength ranged from 16–23 N.mm². These values increases with growing of concentration of used alkali solution as well as with temperature for NaOH treated samples and is comparable with compressive strength for the respective ceramic products sintered at 900 °C.

Because of the rapid evolution in the last decade of science and engineering materials, development of new advanced materials, particularly in construction, we must find solutions, namely, new performed materials, with functional and aesthetic qualities. In recent years, there have been made alternative attempts to reuse various types of wastes, including the incorporation of products in ceramic clay. This theme concerning the achievement of some durable, economic and ecological materials represents a high-level preoccupation in this domain, the problems related to the ecosystem being permanent issues of the century.

In this paper, the synthesis of Al₄SiC₄ used as natural oxide materials by carbothermal reduction was investigated in order to explore the synthesis route with low costs. The samples were calcined by using kaolin grog, aluminum and carbon black as raw materials with the selected proportion at the temperature from 1500 to 1800 ° C for 2 hours under flow argon atmosphere. The phase composition of reaction products were determined by X-ray diffraction. The microstructure and elemental composition of different phases were observed and identified by scanning electron microscopy and energy dispersive spectroscopy. The mechanism of reaction processing was discussed. The results show that Al₄SiC₄ powders composed of hexagonal plate-like particulates with various sizes and the thickness of less than 20 μm are obtained when the temperature reaches 1800 °C.

Three powders of aluminum, silicon and graphite were mixed with the molar ratio corresponding to the chemical composition of Al₄SiC₄, and then a small amount of titanium oxide was added into the mixture. The mixtures were heated at 1973 K in argon, and the Al₄SiC₄ phase was obtained. Conversely, the two phases, Al₄O₄C and TiC, were detected when the increasing of additive amount of TiO₂ was made, and the grain sizes of Al₄SiC₄ were refined from 10~20 μm to 1~5 μm at the same time. Further, the morphology of Al₄SiC₄ without addition of TiO₂ is irregular shape, but changes into tabular structure after adding TiO₂.

Effect of Si contents on reaction-bonded Si₃N₄/SiC composite ceramics under pressureless was investigated. Si₃N₄/SiC composite ceramics were sintered at 1600 °C under nitrogen atmosphere by using SiC powders (1.5μm), Si powders (74μm) with different contents 37~55wt% and sintering additives Y₂O₃ as raw materials. The phases, microstructure and mechanical property were characterized by XRD, SEM, and compressive strength tests. The results demonstrated that when the content of Si powders was 37wt%, the more dense samples with the bulk density of 2.41 g/cm³ and the higher compressive strength of 319 MPa could be obtained under pressureless.

The main aim of this article was to obtain concrete surface quality changes by the usage of different form release agent application. Secondly, to determine blemishes of concrete surfaces and divide them according to combined method provided by two documents and by using computer program: CIB Report No. 24 "Tolerances on blemishes of concrete", GOST 13015.0–83 and "ImageJ". Two different concrete compositions were made: BA1 (low fluidity, vibration is needed) and BA8 (high fluidity, vibration is not needed). Three castings with each formwork were conducted. Water emulsion based form release agent was used. Different applications (normal and excessive) of form release agent were used on the formwork.

Fibrous bodies that contain open porosity can have a very heterogeneous structure that is difficult to characterize in terms of local flow resistance changes within the same sample. This article presents a method that is applicable for a quick analysis of flow distribution even with large samples. In this first attempt to understand how our flow distribution thermal imaging works, we present how the measuring parameters and the results correlate with sample's thickness and density. The results indicate that our method can quickly make a distinction between areas that have different flow resistances because of variations in the sample's density or wall thickness.

The adsorption at room temperature of ferrocene and iron pentacarbonyl on Si(111)7×7 have been studied. On Si(111)7×7,the adsorption sites have been identified by means of scanning tunneling microscopy.We propose a ferrocene adsorption model on Si(111)7×7, i.e., a di-sigma bridging by the molecule between an adatom and a restatom site similar to that proposed for the ethylene. For the iron pentacarbonyl, we have found evidence of a dissociative adsorption on nucleophilic sites. At a higher temperature, an exposure to iron pentacarbonyl lead to the growth of good quality iron silicide. Whereas, silicide carbide is formed on exposure to ferrocene. The films obtained can be explained by means of the chemisorption process at room temperature.

The antibacterial effect of silver can be exploited in the food and beverage industry and medicinal applications to reduce biofouling of surfaces. Very small amount of silver ions are enough to destructively affect the metabolism of bacteria. Moreover, superhydrophobic properties could reduce bacterial adhesion to the surface. In this study we fabricated superhydrophobic surfaces that contained nanosized silver particles. The superhydrophobic surfaces were manufactured onto stainless steel as combination of ceramic nanotopography and hydrophobication by fluorosilane. Silver nanoparticles were precipitated onto the surface by a chemical method. The dissolution of silver from the surface was tested in an aqueous environment under pH values of 1, 3, 5, 7, 9, 11 and 13. The pH value was adjusted with nitric acid and ammonia. It was found that dissolution rate of silver increased as the pH of the solution altered from the pH of de-ionized water to lower and higher pH values but dissolution occurred also in de-ionized water. The antimicrobial potential of this coating was investigated using bacterial strains isolated from the brewery equipment surfaces. The results showed that the number of bacteria adhering onto steel surface was significantly reduced (88%) on the superhydrophobic silver containing coating.

The Ce_0.5Zr_0.4Co_0.1O₂/Pd-Al₂O₃ composite prepared by a mechanochemical route with high BET surface area of 33 m² g⁻¹, exhibited the high oxygen storage capacity (OSC), and high CO oxidation activity at the low temperatures even after calcination at 1000°C for 20 h.

Two approaches were used to obtain nanocrystalline titanium dioxide (TiO₂) photocatalyst powders. Firstly, low-temperature synthesis method and secondly liquid flame spraying. The structural properties of the produced powders were determined with X-ray diffraction, transmission electron microscopy and nitrogen adsorption tests. The photocatalytic properties of the powders were studied with methylene blue (MB) discoloration tests. After discolorations tests, TiO₂ was coagulated with magnetite particles using FeCl₃·6 H₂O at a fixed pH value. Magnetic separation of coagulated TiO₂ and magnetite was carried out by a permanent magnet. The obtained results showed that the particle size of the powders synthesized at low-temperature was very small and the specific surface area high. The phase content of the powder was also shown to depend greatly on the acidity of the synthesis solution. Powder synthesized by liquid flame spraying was mixture of anatase and rutile phases with essentially larger particle size and lower specific surface area than those of low-temperature synthesized powders. The MB discoloration test showed that photocatalytic activity depends on the phase structure as well as the specific surface area of the synthesized TiO₂ powder. The magnetic separation of TiO₂–magnetite coagulate from solution proved to be efficient around pH:8.