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Magnetic Nd-(Fe, Co)-B powders prepared by a modified Pechini-type chemical method are investigated. The effect of 0–100 at.% Co concentration on magnetic properties is shown. The structure and morphology of the powders are studied by electron microscopy. The average particle size is determined by electron microscopy. The internal structure of the nanoparticle agglomerates was explored by transmission electron microscopy. The Nd2Fe14B phase was determined by spot electron diffraction. The dependence of saturation magnetization and coercive force of NdFe1–xCoxB powders on the cobalt content is investigated and discussed. An increasing coercive force is observed as a result of the increase in Co content. It is shown that the absence of phase purity leads to a decrease in the coercive force in comparison with the Nd-based hard magnetic obtained by metallurgical methods.

The results of the study of the phase composition and corrosion resistance of plasma coatings from composite powders based on intermetallics in TiAl with the introduction of non-metallic refractory compounds (SiC or Si3N4) are presented. The plasma coatings were deposited to the specimens of St3, AMg3 and VT6 alloys. The coatings were investigated by the methods of metallographic and X-ray structural phase analysis. The studies of electrochemical properties of the plasma coatings were carried out by the potentiostatic method in a 3% NaCl solution. As initial materials for plasma spraying, composite powders TiAl–SiC, TiAl–Si3N4 produced by the method of mechanochemical synthesis were used. Using the method of X-ray structural analysis, it was revealed that the phase composition of the plasma coatings for the TiAl–SiC system consists of the following phases: TiAl, TiAl3, TiC, Ti5Si3, Ti3AlC, TiO2, and for the coating TiAl–Si3N4 from phases Ti2Al, Ti5Si3, TiN, TiO. The average thickness of the coatings was 200 ± 50 μm, the porosity did not exceed 10%. It was found that the introduction of SiC or Si3N4 into the composition of the composite coating leads to a decrease in the corrosion current in a 3% NaCl solution by about an order of value, and the corrosion resistance of St3, АМg3 and VТ6 alloys increases by 12...13, 8...9, and 1.8...2.0 times, respectively. The service life of the plasma coatings made of TiAl composite powders with the addition of SiC and Si3N4 was calculated. The studied coatings belong to the class of resistant and are capable to protect metals in a 3% NaCl solution for a period from 6 to 10 years. [ABSTRACT FROM AUTHOR]

Studies of the structural-phase state, erosion and corrosion resistance of coatings of the systems TiAl–SiC and TiAl–Si3 N4, produced by the method of supersonic air-gas plasma spraying, are presented. As materials for spraying, composite powders, produced by the method of mechanic and chemical synthesis based on intermetallic TiAl with the addition of non-metallic refractory compounds SiC and Si3 N4 were used. Comparison of the phase composition of the produced coatings of the systems TiAl–SiC and TiAl–Si3 N4 with the phase composition of the composite powder after mechanic and chemical synthesis indicates the course of processes of interaction of TiAl with non-metallic refractory compounds, as a result of which the phases of SiC and Si3 N4 are not observed in the coating. Due to the presence of strengthening phases in the coatings, the erosion resistance of the composite coatings increases by 1.3...1.5 times as compared to the TiAl intermetallic coating. Electrochemical tests established that the coatings of the systems TiAl–SiC and TiAl–Si3 N4 are capable to provide protection of steel, aluminium and titanium base in an environment containing sodium chloride with a 5...155 times increase in resistance. On the basis of the conducted studies of functional properties of the developed composite coatings, the possibility of their use for the protection of parts subjected to erosive wear and corrosion is shown. 15 Ref., 3 Tabl., 4 Fig. [ABSTRACT FROM AUTHOR]

Copyright of Automatic Welding / Avtomatitcheskaia Svarka is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper presents a study of the effect of adding Mo and MoS2 on the microstructure and properties of a powder coating based on austenitic steels. The coatings have been studied using X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), a Vickers hardness tester, and abrasion wear resistance has been determined by the Pin on disk method. The results show that a coating that does not contain Mo and MoS2 consists of the phases g(Fe), M7(C, B)3 and (Fe, Cr)2B. The addition of Mo and MoS2 leads to the formation of phases M23(C, B)6, Mo2(B, C) and Fe3Mo3(C, B), where M = Fe, Cr, Mo. The main goal of these studies was to study characteristics of Mo and MoS2 distribution and the effect of their addition on the microstructure, hardness, and abrasion wear resistance of an alloy coating based on austenitic steels. Composite materials based on austenitic steels obtained by diffusion alloying (Aus0Mo), which has a nearly spherical shape with a diameter of 50–100 μm, have been used for deposition. 3–7 wt. % of Mo powder and 1.0–1.5 wt. % of MoS2 powder with a diameter less than 50 μm have been added in the powder of the composite material based on austenitic steels (Aus3Mo, Aus5Mo, Aus7Mo). Surfacing methods, including gas arc welding with a tungsten electrode, arc welding in shielding gas, plasma surfacing (PTA) and laser surfacing are widely used in industry to increase wear resistance of surfaces. The most important differences between these methods are deposition rate, applicability of materials, substrate dilution, microstructure and hardness stability after exposure to high temperatures, as well as manufacturing cost. Among the methods described above, plasma spraying followed by fusion is a good alternative to other surfacing processes. The coating should not be overheated until it is completely melted, since in this case the primary crystals of chromium carbides and borides pass into a liquid solution and upon subsequent crystallization, form a coarser structure, worsening the quality of the coating. This is precisely what does not occur during plasma spraying followed by reflow; in addition, the method is cheap, coatings are of high quality, competitive wear resistance and high stability of properties at high temperature.

Background. The industrial processing of glauconian sandstones into mineral pigments from the Changi deposit has not been studied. Purpose: To study the structure, composition, properties of the raw material and the obtained samples. Investigate the mineralogical and phase composition, determine the amorphous and crystalline phases of the samples. Methodology. Powder samples were studied by X-ray diffraction and elemental analysis. Both standard, generally accepted research methods in research practice, and special ones using a package of applied programs were used. Originality. Powdery glauconite samples were studied by X-ray phase and elemental analysis, and the structure, composition and properties of the initial raw material and samples of glauconite from the Changi deposit, obtained in the process of enrichment and firing, were studied. Findings. The composition of glauconite-containing samples has been established, semi-quantitative components in the samples have been determined, and the crystal structure of substances has been determined. Investigations were carried out by powder X-ray diffractometry on the XRD-6100 apparatus, with the help of which the main features of glauconite samples were revealed, which are subsequently used to obtain pigments and fillers in the construction industry. [ABSTRACT FROM AUTHOR]

Copyright of Nanosistemi, Nanomateriali, Nanotehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nanosistemi, Nanomateriali, Nanotehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article highlights the importance of the pharmaceutical drugs manufacturing. There are analysis of prescriptions coming from pharmacies in Moscow. There are investigated the structure of extemporaneous drugs in accordance with the classification of the state of aggregation. The article revealed the use of ready-made drugs in extemporaneous technology of powder for children manufacturing. This circumstance is due to the lack of modern pharmaceutical substances in pharmacies. The article deals with the legal aspect of the problem.

Research results of magnetic properties of powder hot-stamp soft magnetic materials of system Fe-P are considered. Presence of uncontrolled impurity in the interface areas, and existence of the deformed frontier area in which iron atoms have local symmetry of the nearest environment below the cubic were established by the Mossbauer spectroscopy.

The dependence of pressings density on the basis of the granulated aluminium powder is investigated. The definition technique of fractal dimension of powder materials surface is offered.

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: Purpose of the study to determine the effectiveness of Anvifen in the case of insomnia and meteosensitivity as comorbid stress-induced disorders., Material and Methods: 67 patients aged 60-70 years were examined, who were randomly divided into two groups: group 1 - 33 patients (20 men, 13 women), group 2 - 34 patients (19 men, 15 women). The average age of group 1 was 62.7 [61; 65] years, group 2 was 63.1 [60; 66] years ( p =0.28). Research methods: questionnaire for scoring subjective characteristics of sleep, assessing the influence of meteosensitivity on daily activity using a numerical rank scale (NRS) for the previous three months. Patients in group 1 took Anvifen 250 mg (capsules) in the morning and afternoon, 500 mg (2 capsules) in the evening at 10 p.m., and upon awakening at night - an additional 250 mg of the drug per capsule. Patients in group 2 took Anvifen powder (extracting it from the capsule) 250 mg in the morning and afternoon, 500 mg in the evening at 10 p.m., and upon awakening at night - an additional 250 mg of the drug. The time from the nightly intake of Anvifen to the onset of sleep was also assessed on a three-degree scale: «fast», «long», «very long». The duration of treatment was 4 weeks., Results: Baseline results of measured parameters did not differ significantly between groups. After completion of treatment, the total score of subjective sleep characteristics improved in 1 st ( p =0.00001) and 2 nd ( p =0.000001) groups. Significant differences from group 1 for the better in group 2 were in «quality of sleep» ( p =0.00027) and «quality of awakening» ( p =0.00001). Weather sensitivity decreased in 1 st ( p =0.00001) and 2 nd ( p =0.000001) groups., Conclusion: Anvifen showed good effectiveness in the treatment of two comorbid conditions of elderly people - insomnia and meteosensitivity. Using the drug in powder form allows you to get a faster and better effect without side-effects.

In the production of tablets direct compression method, wet and dry granulationare used. Dry granulation can be used if materials have sufficient cohesive properties to form granules. Scientific publications of recent years clearly demonstrate the prospects of roller compaction using in pharmaceutical industry. Aim. The aim of work is to generalize available data regarding to the use of compaction in the pharmaceutical industry. Materials and methods. We have studied and analyzed the available scientific sources in order to generalize the available literature on the use of compacting in the production of the tablets. During this study we used methods of observation and systematization analysis. Results. Materials for compaction characteristics of the process, its benefits and conditions of application have been collected and systematized, parameters of process have been selected, theories of compaction have been generalized, the characteristics and examples of compaction equipment have been adduced, and the key characteristics of the material used in the pharmaceutical industry have been demonstrated. Compacting is dry granulation technology in which powder containing active ingredients and excipients are compacted between two opposing spinning rollers by applying mechanical pressure. Compared with the original powder, granules after compression are characterized by much better fluidity and higher density by reducing the volume. The roller consolidation process substantially affects the particle size distribution, flowability, homogeneity, pressing, compaction substances and excipients, therefore, can affect dissolution, time of disintegration, resistance to crushing, abrasion of tablets. The main parameters of compacting are seal and method of its application, conditions and speed of the process. Conclusions. It has been established that the use of compacting decreases or increases particles size to form granules, which leads to improved performance of fluidity powder, granulation avoid moisture induced degradation, improve product stability, prevent segregation, reduction of bulk volume.This indicates the promising future for the compaction technology in the production of medicines that meet pharmaceutical requirements.

Copyright of Electrometallurgy Today / Sovremennaya Elektrometallurgiya is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using the method of thermal hydrolysis of six-water chloride of iron in the regenerative atmosphere, the powders of iron were obtained consisting of particles in the size range of 75-150 nanometers. The morphology and magnetic properties of the obtained alloy are investigated.

Influence of electrolysis parameters (concentration of silver in the electrolyte, current density, additives of surface active agents, a reversive current) on the granulometric composition and structure of silver powders is considered. Optimum conditions of the process are revealed.

Research results of magnetic properties of powder hot-stamp soft magnetic materials of system Fe-P are considered. Presence of uncontrolled impurity in the interface areas, and existence of the deformed frontier area in which iron atoms have local symmetry of the nearest environment below the cubic were established by the Mossbauer spectroscopy.

The dependence of pressings density on the basis of the granulated aluminium powder is investigated. The definition technique of fractal dimension of powder materials surface is offered.

Subject of Study. The paper deals with preparation processes of ultradisperse, homogeneous powder Sr1-хNdхF2+х (х= 0.003-0.2), with use of ammonium fluoride as the fluorinating agent taken over 114-120 % from stoichiometry. Method. Nitrate of strontium, neodymium nitrate hexahydrate, with the content equal to 99. 99 % of the basic substance and ammonium fluoride were used as the source of substances. Activated powders of strontium fluoride were obtained by the method of deposition from aqueous solutions by washing the precipitate with a solution of ammonium fluoride, taken over 114 - 120% from stoichiometry. The washed precipitate was centrifuged for 5-7 min, dried in the air at 30-350 C. Heat treatment of the dried precipitate was carried out in two stages: the first stage at the temperature of 200- 2500 C for 0.5-1 hour, the second one at 550- 6000 C for 2-3 hours. X-ray analysis of the synthesized samples was carried out on a Bruker D8 Advance diffractometer, radiation Cu K. The size and shape measuring of the particles of activated strontium fluoride was carried out by means of electron microscope Carl Zeiss NVision 40. The content of neodymium in activated powders of strontium fluoride was determined by the method of spectral emission analysis on the device LEA - S500. Chemical analysis for determination of ammonium ion (NH4+) content in the obtained samples was performed by the method of Kjeldahl. Calculations of lattice parameters, size of coherent scattering regions and the values of micro-deformations were carried out by TOPAS program. Main Results. Preparation processes of ultradisperse, homogeneous powder Sr1-хNdхF2+х (х= 0.003-0.2), with use of ammonium fluoride as the fluorinating agent taken over 114-120 % from stoichiometry, provides obtaining the firm solution Sr1-x-yNdx(NH4)yF2+x-y of the cubic fluorite structure. It has been found out that the morphology and size of the resulting product depend on the quantity of excess ammonium fluoride. The changes in the morphology of the particles from nano – and microcubes to a plate shape were made clear by varying the quantity of excess ammonium fluoride from 114% to 120%. The particle size significantly decreased with increasing excess of ammonium fluoride from 114% to 120%. After heat treatment of the obtained powders agglomeration of cubic morphology particles to a size equal to 50-350 nm without changing their shape occurred. The plate-like particles have got a rounded shape after heat treatment with size between 50 and 200 nm. Practical Relevance. Obtained mixtures with ammonium fluoride excess over 114 % and 120 % are promising for use in the technology of ceramics by hot pressing.

The core of this research is to study tribotechnical characteristics of powder composite materials under the conditions of chain couplings functioning. We recommend utilizing powder composite materials with a rough heterogeneous structure to produce complex shaped half-couplings toothings. [ABSTRACT FROM AUTHOR]

High porous compositions have been prepared from ultradispersed powders on the base of activated carbons obtained from polyethyleneterephtalate waste. Porous structure of carbons obtained have been characterized. Sorption properties have been evaluated. The approbation of accumulative ability concerning methane storage in tablet composition have been done. [ABSTRACT FROM AUTHOR]

The review contains information about the fluorescent properties of natural teeth, fluorescent additives, fluorescent liquids for staining zirconium dioxide, fluorescent powders, pastes, glazes, and cements for zirconia, methods for measuring fluorescence. Factors affecting the fluorescent properties of ceramics are also reported.