Institute of Non Ferrous Metals
Institute of Non Ferrous Metals
Podworny J.,Institute of Ceramics and Building Materials |
Staszewski M.,Institute of Non Ferrous Metals |
Wojsa J.,Institute of Ceramics and Building Materials
Journal of Applied Crystallography | Year: 2017
Owing to the phase transition of the tetragonal form of ZrO2 into the monoclinic one, caused by mechanical stresses, preparation of powder samples for quantitative phase analysis by the X-ray diffraction method should be avoided. The process of grinding of zirconia sinters leads to considerable changes in their phase composition. For this reason, a quantitative phase analysis should be conducted on solid samples not subjected to mechanical stresses, irrespective of problems appearing during experiments and analysis. One such problem is preferred crystallographic orientation (texture). This paper describes the influence of a preferred crystallographic orientation on the quantitative phase analysis conducted on solid samples and presents the results of an analysis in which corrections for uniaxial and multiaxial textures were applied. It was found that the examined samples had a very weak but nonzero multiaxial texture. The share of the randomly oriented fraction in the examined sinters was determined to be ca 94?vol.% and the share of the textured fraction ca 6?vol.%. From the statistical point of view, in the case of small amounts of the textured fraction, a correction on one distinguished crystallographic plane can overcome this problem. In the case of the slightly textured sinters of metering nozzles subjected to investigation here, the correction related to all the unique directions was statistically insignificant because the textured part corresponds to only a small volume fraction. However, corrections related to all texture axes considerably improve the fit of the calculated X-ray pattern with the experimental one and help to better characterize the examined materials.This paper describes the multiaxial texture of zirconia sinters used as metering nozzles and describes the correct method of phase composition determination using X-ray diffraction. Owing to phase composition changes during sample preparation, testing should be carried out on solid samples and the results corrected. © International Union of Crystallography, 2017.
Hawelek L.,Institute of Non Ferrous Metals
Acta Physica Polonica A | Year: 2016
The effect of three types of topological defects, single vacancy, double vacancy and the Stone-Thrower-Wales defect on the atomic arrangement in a single graphitic layer is studied using computer simulations. The topological defects were positioned on the perfect hexagonal graphitic layer 20 Å in diameter with different distance from the layer edge and then the geometry of the system was independently optimized using the reactive bond order potential, the semi-empirical quantum-chemical PM7 and the density functional theory method. Curvature and the distortion of the graphitic layer caused by the defects are analyzed and their influence on the pair correlation function is discussed.
Fulara I.,Institute for Ecology of Industrial Areas |
Czaplicka M.,Institute of Non Ferrous Metals
Journal of Separation Science | Year: 2012
Polybrominated diphenyl ethers (PBDEs) are a group of persistent organic pollutants. They are used as flame retardants in plastics, paints, varnishes and textile materials. PBDEs pose great risk to the environment because of their high persistence and ability to get into the environment easily due to the lack of chemical bonds with the matrix of materials, to which they are added. Global research studies confirmed the occurrence of those compounds in the majority of elements of water and land environment. Analysis of PBDEs in environmental samples is one of the specific analytical methods of criteria that comprise low detection limits and high selectivity. The analysis of PBDEs in environmental samples is one of the specific analytical methods, in which the main criteria are low detection limits and high selectivity. In this article, a literature review of methods for environmental sample preparation and analysis of the PBDE content was presented. The article discusses the potential of modern extraction techniques such as: solid-phase microextraction, single-drop microextraction, dispersive liquid-liquid microextraction, microwave-assisted extraction, cloud point extraction, hollow fibre-liquid phase microextraction and others for the separation of PBDEs from environmental samples with a complex matrix. Among the methods for qualitative and quantitative determination of PBDEs, a particular focus was put on gas chromatography/mass spectrometry with various injection techniques and different types of sample ionisation. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Dolata A.J.,Silesian University of Technology |
Dyzia M.,Silesian University of Technology |
Boczkal S.,Institute of Non Ferrous Metals
Materials Today: Proceedings | Year: 2016
The structure and properties of the interface between the components are the primary factor in determining the properties of composite materials, in addition to the properties of the matrix and reinforcing phase. The influence of aluminium matrix chemical composition and its modification on the interface microstructure in Al/SiCp+Cgp hybrid composite were presented. The composites structure was examined under an Olympus GX71 light microscope (LM). Scanning electron microscope (SEM) with an attachment for the chemical analysis (EDS) in microregions was used for the composite microstructure characterization. © 2016 Elsevier Ltd.
Zubkova V.,Jan Kochanowski University |
Czaplicka M.,Institute of Non Ferrous Metals
Fuel | Year: 2012
Changes in the structure of plasticized high, medium, and low volatile bituminous coals caused by dichloromethane extraction were studied using an X-ray method of quantitative phase analysis. The FT-IR and GC-MS methods were used to investigate the differences in composition of the dichloromethane soluble material from the coals studied. It was stated that the removal of dichloromethane soluble material leads to an increase in the amount of the crystallite phase. The contribution of hydrogen bonds and aromatic ring stretching in formation of bands on the FT-IR spectra of the extracts from plasticized coals increases but the contribution of the CO bonds decreases. The ratio of the amount of selected PAHs in extracts of plasticized high, medium, and low volatile bituminous coals to the amount of the same PAHs in extracts of raw coals is 5.7, 20.9, and 0.6 correspondingly. © 2012 Elsevier Ltd. All rights reserved.
Szymanski W.,Institute of Non Ferrous Metals
Archives of Metallurgy and Materials | Year: 2016
Studies were conducted to improve the mechanical properties of composites based on 7475 aluminium alloy reinforced with Al3Ti particles fabricated by the "in situ" process. The first step involved "dissolving" of titanium in the liquid aluminium alloy and fabricating in this way composite materials with different content of the reinforcing phase (15-45wt%). A relationship between the composite hardness and content of the reinforcing phase was confirmed. The second step involved the improvement of cohesion between the reinforcing particles and composite matrix. By extrusion of samples in semi-solid state, an average increase in hardness by 15-20% relative to the unextruded composite was obtained. In the third step, the fabricated composite was subjected to a heat treatment corresponding to the state T6 in 7475 alloy, which raised the hardness by about 30%. Structure examinations carried out by means of optical microscopy and scanning electron microscopies as well as the results of hardness measurements were described. They enabled estimating the effect of the content of produced Al3Ti particles, and of the extrusion process in semi-solid state and heat treatment parameters on the composite properties. In compression test, the yield strength and compressive strength of the heat-treated composites were determined.
Niedbala J.,Institute of Non Ferrous Metals
Bulletin of Materials Science | Year: 2015
Ni-Mo+PTh composite coatings were prepared from nickel-molybdenum galvanic bath with the addition of thiophene (Th) and HClO4 as result of two processes: induced Ni-Mo alloy deposition and PTh polymerization. A scanning electron microscope was used for surface morphology characterization of the coatings. The Scanning ElectrochemicalWorkstationM370 was used to the surface map of the tested composite coatings. The chemical composition of the coatings was determined by the energy-dispersive spectroscopy (EDS) method. It was stated that the surface of the coatings are characterized by the presence of Ni-Mo particles and polythiophene agglomerates. Electrochemical corrosion investigations of coatings were carried out in the 5 M KOH solution, using voltammetry and electrochemical impedance spectroscopy (EIS) methods. On the basis of these research works it was found that the composite Ni-Mo+PTh coatings are more corrosion resistant in alkaline solution than Ni-Mo. The reasons for this are the presence of the polymer on the surface of the coatings and a decrease of corrosion active surface area of the coatings. © Indian Academy of Sciences.
Gotfryd L.,Institute of Non Ferrous Metals |
Pietek G.,Institute of Non Ferrous Metals
Physicochemical Problems of Mineral Processing | Year: 2013
Several copper extractants have been examined in laboratory glassware with a special attention paid to their behavior towards cations others than copper(II). In the studies 25 vol. percent of hydrocarbon (Exxsol D80 AZ) solutions of six industrial copper extractants have been used. They were mainly reagents of hydrooxime type (LIX 860N-IC., LIX 984, LIX 984N., LIX 84-1, Acorga M5640) and diketone type LIX 54-100. Individual isotherms of independent extraction of copper(II) and selected cations (Fe3+, Fe2+, Co2+, Ni2+, Zn2+, Mn2+, Cd 2+, Mg2+) versus equilibrium pH have been compared. Investigations have been conducted with synthetic 0.1 mol/L solutions of their sulfates. The values of pH50%, - parameter defined as an equilibrium pH at the moment of half-and-half extraction of the investigated cationic species have been presented. Also δpH50%" that is differences between values of pH50v. for specific cation Me(II) and copper(II): δpH50% = pH50%(Me) - pH50%(Cu), have been given. In addition to that 25% LIX 984 has been used in counter-current pilot trials for copper(II) extraction from naturally contaminated solutions produced by bioleaching of industrial sulfide copper concentrate to observe behavior of investigated contaminants such as correlations between their real co-extraction with copper(II) and the position of their extraction on the pH scale. Copper electrolyte/strip solution, working alternately within close loop of coupled stripping - electrowinning system, has been analyzed during consecutive cycles to observe building up of the contaminants concentrations in the course of test.
Jaworek K.,Institute of Non ferrous Metals |
Czaplicka M.,Institute of Non ferrous Metals
Polimeros | Year: 2013
The paper presents two methods for determination of phthalates in polymer materials. The methods compared were gas chromatography combined with the mass spectrometry (GC/MS) and gas chromatography with electron capture detector (GC/ECD). The GC/ECD technique was chosen for this comparison, because the ECD detector was one of few capable of detecting phthalates. In both cases the same procedure of sample preparation with ultrasonic extraction was applied. Overall recoveries were 76-100 % with relative of standard deviation (R.S.D.) values in the range 0.6-19 %. The values of limit of detection (LOD) for GC/MS method ranged from 3.46 μg mL-1 to 10.10 μg mL-1, depending on the determined phthalate, while in case of the GC/ECD method they were in the range from 2.97 μg mL-1 to 4.29 μg mL-1. The methods were applied for determination of: dimethyl phthalate, diethyl phthalate, di-n-butyl phthalate, benzyl butyl phthalate, bis(2-ethylhexyl) phthalate, diisononyl phthalate, diisoocyl phthalate in polymer material. The seventeen kinds of samples were analyzed. Most of the materials selected for the analyses were made from polyethylene (PE), polyvinyl chloride (PVC) and polystyrene (PS).
Kolano-Burian A.,Institute of Non Ferrous Metals
Journal of Applied Physics | Year: 2013
The magnetic domain structure is a specific property of ferromagnetic materials. The main magnetic properties and core losses depend on its configuration and dimensions. The aim of this work was to determine a relationship between the domain structure, observed by means of magneto-optic Kerr effect on the surface of the Fe14.7Co58.8Cu 1Nb3Si13.5B9 (FeCo58) and Fe 13.8Co65Cu0.6Nb2.6Si 9B9 (FeCo65) toroidal cores, and the induced transverse magnetic anisotropy Ku and magnetic characteristics B = f(H). The transverse magnetic anisotropy has been induced in the FeCo58 and FeCo65 amorphous cores by annealing at the temperature of 420-500 °C under an external magnetic field of 500 kA/m. It was found that the FeCo58 cores, characterized by three times smaller Ku compared to the FeCo65 cores, had different domain structures than those of the FeCo65 cores. The domain structure of the FeCo65 cores is characterized by almost parallel domains of an average width d varying from 28 to 50 μm after heat treatment at the temperatures ranging from 420 to 500 °C. © 2013 AIP Publishing LLC.