bluuebunny/crossref_metadata_2025 huggingface dataset:
Upper Albian and Cenomanian (Cretaceous) ammonites from the Debarsu Formation (Yazd Block, Central Iran)
Authors: Wilmsen Markus , Storm Marisa , Fürsich Franz Theodor , Majidifard Mahmoud Reza
Published: January 2014

Wilmsen, M., Storm, M., Fürsich, F.T. and Majidifard, M.R. 2013. Upper Albian and Cenomanian (Cretaceous) ammonites from the Debarsu Formation (Yazd Block, Central Iran). Acta Geologica Polonica, 63 (4), 489-513. Warszawa. New ammonite faunas consisting of 13 taxa provide the first reliable biostratigraphic dating of the Debarsu Formation of the Yazd Block, west-central Iran, indicating several levels in the Upper Albian and Lower Cenomanian, while a foraminiferal assemblage places the top of the Formation in the Middle Turonian. Among the identified ammonite taxa, Acompsoceras renevieri (Sharpe, 1857) is recorded from Iran for the first time. The upper part of the lower Upper Albian is proved by the occurrences of mortoniceratines of the Mortoniceras (M.) inflatum Zone in the lowermost part of the Debarsu Formation. For the upper Upper Albian (traditional Stoliczkaia dispar Zone), the M. (Subschloenbachia ) rostratum and M. (S.) perinflatum zones are proved by their index taxa. However, there is no evidence of the terminal Arrhaphoceras (Praeschloenbachia) briacensis Zone. The upper part of the lower Lower Cenomanian Mantelliceras mantelli Zone (M. saxbii Subzone) is proved by M. saxbii and M. cf. mantelli. Below, there is an ammonite- barren interval of ca. 100 m in thickness between M. (S.) perinflatum zonal strata and the M. saxbii Subzone. The upper Lower Cenomanian is documented by the presence of typically M. dixoni zonal ammonites such as Acompsoceras renevieri. Upper Cenomanian and Turonian ammonites have not been found in the upper part of the Debarsu Formation, but micro-biostratigraphic evidence (planktonic foraminifers) from the uppermost part of the formation indicate that the formation ranges into the Turonian. For the development of the major tectonic unconformity at the base of the overlying Haftoman Formation (which yielded Lower Coniacian inoceramids near its base), only 2-3 myr remain, stressing the geodynamic activity of Central Iran during mid-Cretaceous times.
Late Maastrichtian foraminiferids and diatoms from the Polish Carpathians (Ropianka Formation, Skole Nappe): a case study from the Chmielnik-Grabówka composite section
Authors: Gasiński M. Adam , Olshtynska Alexandra , Uchman Alfred
Published: January 2014

Gasiński, M.A., Olshtynska, A. and Uchman, A. 2013. Late Maastrichtian foraminiferids and diatoms from the Polish Carpathians (Ropianka Formation, Skole Nappe): a case study from the Chmielnik-Grabowka composite section. Acta Geologica Polonica, 63(4), 515-525. Warszawa.

Well-preserved foraminiferids have been found in the Chmielnik-Grabowka section (Skole Nappe, Polish Carpathians). The Abathomphalus mayaroensis (late Maastrichtian) and Racemiguembelina fructicosa (earlylate Maastrichtian) standard planktonic foraminiferal biozones have been recognized, based on the occurrence of their respective index species. Sediments of the R. fructicosa Zone contain diatoms, which are a rare component of Cretaceous flysch microfossil assemblages in the Carpathians. The diatom frustules and some foraminiferid tests are pyritized, probably after burial in the sediment, below the redox boundary or in the oxygen- deficient microenvironment inside the frustules or tests of microfossils; the presence of trace fossils and bioturbational structures in the same bed indicate an oxygenated sea floor.
Scaphitid ammonites from the Upper Cretaceous of KwaZulu-Natal and Eastern Cape Province, South Africa
Authors: Kennedy William James , Klinger Herbert Christian
Published: January 2014

Kennedy, W.J. and Klinger, H.C. 2013. Scaphitid ammonites from the Upper Cretaceous of KwaZulu-Natal and Eastern Cape Province, South Africa. Acta Geologica Polonica, 63 (4), 527-543. Warszawa.

Scaphitid ammonites are described and illustrated from the Upper Cretaceous of the coastal region of north-eastern South Africa. Scaphites kieslingswaldensis Langenhan and Grundey, 1891, Scaphites manasoaensis Collignon, 1965, and Yezoites concinna sp. nov. occur in the Coniacian part of the St Lucia Formation in northern KwaZulu-Natal. A further Yezoites sp. may also be from this level. Argentoscaphites corrugatus sp. nov. occurs in the Santonian to Lower Campanian Mzamba Formation on the northernmost coast of Eastern Cape Province. Yezoites australis sp. nov. occurs in the Upper Santonian part of the St Lucia and Mzamba formations of these areas, and Scaphites reesidei Collignon, 1969, is recorded from the Lower Campanian part of the Mzamba Formation. The scaphitid assemblage includes species previously described from Western Europe and Madagascar, together with Argentoscaphites, previously known only from Patagonia (and possibly South India). Dimorphism is recognised in Scaphites reesidei, Yezoites concinna sp. nov. and Y. australis sp. nov. Argentoscaphites corrugatus sp. nov. and Yezoites sp. are represented by microconchs only. Dimorphism has not been recognised in Scaphites kieslingswaldensis.
THE EFFECT OF TEMPERATURE PYROLYSIS PROCESS OF USED TIRES ON THE QUALITY OF OUTPUT PRODUCTS
Authors: Jasminská Natália , Brestovič Tomáš , Čarnogurská Mária
Published: January 2014

Pyrolysis together with gasification and combustion create a group of so called thermic processes. Unlike the combustion it is based on thermic decomposition of organic materials without any access of oxidative media. Within the pyrolytic process, three main fractions are created: solid residue, pyrolytic gas and organic liquid product - pyrolytic oil. The presented article examines the effects of pyrolysis operational conditions (above all, temperature) on gas products, solid residues and liquid fractions.
SINGULAR FRACTIONAL CONTINUOUS-TIME AND DISCRETE-TIME LINEAR SYSTEMS
Authors: Kaczorek Tadeusz
Published: January 2014

New classes of singular fractional continuous-time and discrete-time linear systems are introduced. Electrical circuits are example of singular fractional continuous-time systems. Using the Caputo definition of the fractional derivative, the Weierstrass regular pencil decomposition and Laplace transformation the solution to the state equation of singular fractional linear systems is derived. It is shown that every electrical circuit is a singular fractional systems if it contains at least one mesh consisting of branches with only ideal supercondensators and voltage sources or at least one node with branches with supercoils. Using the Weierstrass regular pencil decomposition the solution to the state equation of singular fractional discrete-time linear systems is derived. The considerations are illustrated by numerical examples.
POSITIVE MINIMAL REALIZATION OF CONTINUOUS-DISCRETE LINEAR SYSTEMS WITH ALL-POLE AND ALL-ZERO TRANSFER FUNCTION
Authors: Sajewski Łukasz
Published: January 2014

The positive and minimal realization problem for continuous-discrete linear single-input and single-outputs (SISO) systems is formulated. Two special case of the continuous-discrete systems are given. Method based on the state variable diagram for finding a positive and minimal realization of a given proper transfer function is proposed. Sufficient conditions for the existence of a positive minimal realization of a given proper transfer function of all-pole and all-zero systems are established. Two procedures for computation of a positive minimal realization are proposed and illustrated by a numerical examples.
THE DYNAMIC PERFORMANCE ANALYSIS OF THE FOIL BEARING STRUCTURE
Authors: Żywica Grzegorz
Published: January 2014

Foil bearings are a variety of slide bearings in which an additional set of foils is applied between journal and bush, in order to improve the selected static and dynamic properties. Engineers and researchers from all over the world investigate bearings of this type since many years - both from numerical as well as experimental point of view. Due to the complexity of construction, the reliable simulation models are all the time being searched for. This paper discusses the important stages of elaboration of the structural supporting layer numerical model of the foil bearing as well as results of verification tests. The main goal of the conducted study was assessment of reliability of the elaborated numerical model, in scope of dynamic properties. In the near future it will be used for elaboration of the numerical model of the entire foil bearing, which will take into account also phenomena in fluid-film layer. Those models will be used together to describe bearing system in operation.
THIN-WALLED EPOXY-GLASS FIBRE BEAMS SUBJECTED TO PURE BENDING
Authors: Kubiak Tomasz , Kołakowski Zbigniew
Published: January 2014

Buckling and postbuckling behaviour of thin-walled channel section beam made of epoxy-glass composite have been considered. The beams under analysis was subjected to pure bending. The main aim was check the influence of ply arrangement on buckling load and postbuckling behaviour and validate the authors analytical-numerical method by commercial finite element method software. Mentioned analytical-numerical method has been developed for more than 25 years in Department of Strength of Materials. This method uses asymptotic Koiter theory for conservative systems in the second order approximation modified by Byskov and Hutchinson. Additionally, using the finite element method software the influence of ply arrangement on failure load were checked.
INFLUENCE OF TEMPERATURE AND LOADING PROGRAM ON THE FATIGUE LIFE OF STEEL P91
Authors: Mroziński Stanisław , Piotrowski Michał
Published: January 2014

In this paper there are shown the results of low-cycle fatigue testing of steel P91 samples. During the testing there was conducted a fixed amplitude loading testing as well as programmed loading with various sequence degrees of the program. The testing was done in two temperatures: T=20°C and T=600°C. During the testing a cyclic steel weakening was observed without a clear period of stabilization. Greater changes of the cyclic properties were observed in temperature T=600°C. The influence of temperature on the fatigue life was determined in this paper. This influence is dependent on the degree of strain. It’s a minor one in the range of big strain and increases in the process of decreasing the degree of strain. Furthermore, the impact of the loading program type was determined on the test results and fatigue life calculations
DAMAGE MODELING IN GRADED LAYER SYSTEM
Authors: Petaś Michał , Mróz Krzysztof , Doliński Krzysztof
Published: January 2014

The simplified approach to the modelling of low cycle fatigue (LCF) of functionally graded materials (FGM) based on the continuum mechanics is presented. The fatigue damage model takes into account the mechanical part of the load and a constant service temperature. The concept of FGM as a particle-reinforced metal-matrix composite with gradual change of the reinforcement fraction is used. The FGM is considered as a material consisting of homogeneous layers containing different volume fractions of the reinforcement. The variation of the reinforcement fraction changes the material properties for each layer. The different material properties are obtained according to modified rule of mixture. Since the fatigue damage of metal matrix composites is strongly influenced by the inelastic deformation of the metallic matrix, the constitutive equations of LCF damage model are taken into consideration. The combined isotropic/ kinematic hardening model with linear behaviour of isotropic and kinematic parts of hardening is adopted. The damage scalar parameter is associated with the plastic energy dissipation which is used to update the material properties. The fatigue damage model presented in this paper is applied to the fatigue damage analysis of the cooling channel of thruster used in space shuttles and rockets.
INVESTIGATION OF MR FLUIDS IN THE OSCILLATORY SQUEEZE MODE
Authors: Sapiński Bogdan , Horak Wojciech , Szczęch Marcin
Published: January 2014

The paper summarises the results of laboratory testing of three commercially available magnetorheological (MR) fluids operated in the oscillatory squeeze mode. Tested fluids include the Basonetic 204 and Basonetic 4035 (BASF) and MRF-122EG (Lord Corporation). The oscillatory squeeze mode produces large forces at small displacements. This feature may be well utilised in fabrication of new MR devices. The purpose of the experiments was to evaluate the suitability of MR fluids for applications in MR vibration dampers being developed under the current research project. The results enable a comparative analysis of investigated fluids and verification of phenomena encountered in the oscillatory squeeze mode and reported in the literature.
AN ANTICRACK IN A TRANSVERSELY ISOTROPIC SPACE
Authors: Kaczyński Andrzej
Published: January 2014

An absolutely rigid inclusion (anticrack) embedded in an unbound transversely isotropic elastic solid with the axis of elastic symmetry normal to the inclusion plane is considered. A general method of solving the anticrack problem is presented. Effective results have been achieved by constructing the appropriate harmonic potentials. With the use of the Fourier transform technique, the governing system of two-dimensional equations of Newtonian potential type for the stress jump functions on the opposite surfaces of the inclusion is obtained. For illustration, a complete solution to the problem of a penny-shaped anticrack under perpendicular tension at infinity is given and discussed from the point of view of material failure.
DEPENDENCE OF CREEP FAILURE PROBABILITY ON THE SIZE OF METALLIC SPECIMENS
Authors: Nowak Krzysztof
Published: January 2014

The occurrence of statistical size effect is considered for damage in creep conditions. The numerical and experimental analysis have been performed. The obtained results are ambiguous. Numerical models confirm the scale effect which can be statistical or deterministic one. But this effect has no experimental verification. It may suggest that the weakest link model cannot be applied in creep conditions. Explanation of this needs further investigations
Ferroelectric–Ferromagnetic Composites Based on PZT Type Powder and Ferrite Powder
Authors: Bochenek D. , Niemiec P. , Zachariasz R. , Chrobak A. , Ziółkowski G.
Published: January 2014

A ferroelectric-ferromagnetic composites based on PZT powder have been obtained in presented work. The main aim of combination of ferroelectric and magnetic powders was to obtain material showing both electric and magnetic properties. Ferroelectric ceramic powder (in amount of 90%) was based on the doped PZT type solid solution while magnetic component of the composite was nickel-zinc ferrite Ni1-x ZnxFe2O4 (in amount of 10%). The synthesis of components of ferroelectric-ferromagnetic composite was performed using the solid phase sintering. Final densification of synthesized powder has been done using free sintering. For obtained of ferroelectric-ferromagnetic composites the XRD, the microstructure, EDS, dielectric, magnetic, internal friction and electrical hysteresis loop investigations were performed. Obtained results shown the correlations between the magnetic subsystem and the electrical subsystem of the ferroelectric-ferromagnetic composites. Such properties of obtained composites give the possibility to use them in memory applications of new type.
Structure and Properties of Zn-Ti0.2-Cu0.15 Single Crystal Containing Eutectic Precipitates
Authors: Boczkal G.
Published: January 2014

Some structure observations for the Zn-Ti0.2-Cu0.15 single crystal obtained by the Bridgman method are presented. The structure contains (Zn) - phase with inclusions of Zn16Ti inter-metallic compound. The Zn16Ti intermetallic compound is localized within the eutectic precipitates. A morphology of the Zn16Ti compound varies according to the solidification condition imposed during the single crystal growth. The block, great size particles are a characteristic element for the alloy which composition is situated nearly the eutectic point in the phase diagram. These particles were not observed previously in the hypoeutectic Zn-Ti alloys. Mechanical properties of the obtained single crystals are also investigated. Critical resolved shear stress (CRSS) during deformation in a basal slip system (0001)<11-20>is determined. The changes of the CRSS for the Zn-Ti0.2-Cu0.15 single crystals within the range of temperatures from 200K to 370K are presented. The obtained data are compared with previously investigated results for the (Zn) single crystals containing lower (hypoeutectic) titanium addition
A Theoretical Investigation on the Electron Structures of Al-Based Intermetallic Compounds
Authors: He Y. , Zhi W. , Rong C.
Published: January 2014

Theoretical investigations were performed to study on alloying stability, and electronic structure of (AlCu3, AlCu2Zr and AlZr3). The results show that the lattice parameters obtained after full relaxation of crystalline cells are consistent with experimental data, and these intermetallics have a strong alloying ability and structural stability due to the negative formation energies and the cohesive energies. The further analysis find out that single-crystal elastic constants at zero-pressure satisfy the requirement of mechanical stability for cubic crystals. The calculations on Poisson’s ratio show that AlCu3 is much more anisotropic than the other two intermetallics. In addition, calculations on densities of states indicates that the valence bonds of these intermetallics are attributed to the valence electrons of Cu 3d states for AlCu3, Cu 3d and Zr 4d states for AlCu2Zr, and Al 3s, Zr 5s and 4d states for AlZr3, respectively; in particular, the electronic structure of the AlZr3 shows the strongest hybridization.
Mathematical Modeling and Industrial Experiment of Liquid Steel Flow in the Three Outlets Continuous Casting Bloom Tundish
Authors: Cwudzinśki A.
Published: January 2014

The dynamic development of the continuous steel casting (CSC) process has resulted in the application of this technology to the casting of steel semi-finished products on a mass scale. In the CSC process, before the cooling and solidification of liquid steel commences, the liquid metal dynamically flows through the steelmaking ladle, the tundish and the mould. Therefore, the control of steel flow is the key to the correct process. One of the metallurgical device in which the control of steel flow hydrodynamics is of crucial importance is the tundish. The subject of investigation within the present study was a three-nozzle tundish designed for casting of blooms. The software program Ansys-Fluent R was employed for the analysis of tundish operation. For the verification of the correctness of obtained results, an industrial experiment was carried out. For modification of the hydrodynamic conditions within the working volume of the tundish, two flow control devices were proposed, namely: a dam and a dam with an overflow window. The outcome of performed computer simulations were liquid steel flow fields and residence time distribution curves.
The Effect of Shielding Gas Composition on Microstructure and Abrasive Wear Resistance Fabricated with PTA Alloying Technique
Authors: Çay V.V. , Ozan S. , Gök M.S. , Erdoğan A.
Published: January 2014

In this study, SAE 1020 steel surfaces were separately alloyed with preplaced high-carbon-ferro-chromium (FeCr), ferro-molybdenum (FeMo) and ferro-titanium (FeTi) powders by using plasma transferred arc (PTA) heat source. By using three different types of shielding gas compositions during the alloying process, the study investigated the effects of modified shielding gas composition on the microstructure, hardness, and abrasive wear resistance of specimens. The most homogenous microstructure and the highest wear resistance was obtained in the gaseous environment which included 3% of H2. Increasing this rate to 5 % in the shielding gaseous composition caused gaps and pores in the microstructure and caused a decrease in the wear resistance. The x-ray examinations of the specimens identified ferro-molybdenum and ferro-titanium solid solutions, ferrit, austenite and martensite phases in their microstructure as the first phase and FeC, Cr7C3, Cr3C2, Fe3C, Fe7C3, MoC and TiC phases as the second phase. As a result, it was concluded that changes in shielding gas composition in surface alloying process affected specimens’ microstructure and abrasive wear properties.
Entall - Thermodynamic Database of Alloys
Authors: Dębski A.
Published: January 2014

Li-Si, Ag-Ca, B-Li, Ca-Li and Al-Li belong to the group of application alloys. The Entall database includes experimental data on the enthalpy of formation of the intermetallic phases belonging to the mentioned systems, as well as software for the calculation of other thermodynamic functions. The presented Entall database is the first proposal of a thermodynamic property data, which will be gradually extended by new metal alloy systems. It is a free database, available at www.entall.imim.pl.
Heat Exchange in the System Mould – Riser – Ambient. Part II: Surface Heat Emission from Open Riser to Ambient
Authors: Krajewski P.K. , Gradowski A. , Krajewski W.K.
Published: January 2014

The subject of the paper is heat exchange in the system casting - riser - ambient. The examinations were focused on evaluating temperature dependence of the coefficient of heat exchange from open (not shielded) top surface of riser to ambient. The examinations were carried out on the open surface of cast steel riser, of temperatures 1000-1500°C. On the basis of the performed examinations it was stated that heat emission coefficient changes its mean values by about 50% during feeding process of the mild steel casting, i.e. from about 0.28 in liquid state to about 0.42 at temperatures close to solidus. This wide range of surface heat emissivity changes should be taken into account when boundary conditions are formulated in elaborated models of solidification and in designing risering systems.
The Kinetics of Aluminium Evaporation from the Ti-6Al-4V Alloy
Authors: Siwiec G.
Published: January 2014

In the paper, results of a kinetic analysis of aluminium evaporation from the Ti-6Al-4V alloy are presented. The analysis was performed based on the findings obtained during the alloy smelting in the vacuum induction furnace at 5 Pa to 1000 Pa and at 1973 K, 1998 K and 2023 K.
Evaluation of the Chemical Composition and Microcleanliness of the Steel Samples from the Heavy Forging Ingot
Authors: Michałek K. , Tkadleckova M. , Gryc K. , Machovcak P.
Published: January 2014

The paper presents new results obtained from the evaluation of the chemical composition, microcleanliness and structure of the 90-ton heavy ingot cast in two successive heats, in which the content of Cu and Ni was intentionally modified in order to assess the degree of mutual mixing of the two heats in the ingot volume during the steel casting and solidification. For determination of chemical composition, spectral analysis and LECO were used. Microcleanliness evaluation was carried out on a Hitachi microanalytical complex equipped with the energy-dispersive spectrometer Vantage. To assess the composition of oxide non-metallic inclusions ternary diagrams were used. Structure of the basic steel matrix was induced by etching. The evaluation showed that in the casting of two successive heats, a certain degree of inhomogeneity of chemical composition, especially in the lower part of the ingot can be assumed in case of different composition. A greater segregation of sulphur in the central top part of the ingot was also detected. However, microcleanliness of the entire ingot is in general very good with low proportions of non-metallic inclusions.
The Role of MW Plasma Treatment on the Corrosion Resistance of Stainless Steels
Authors: Kasprzyk D. , Stypuła B. , Kustrowski P. , Drozdek M.
Published: January 2014

Two stainless steels (S32404 duplex and S32615 austenitic) were subject to the carbon/nitrogen plasma treatment to examine the role of alloy composition and structure in the behavior of surface during modification. The modification process was performed in the electron cyclotron resonance (ECR) micro wave plasma system, with the frequency of 2.45 GHz and the generator power of 350 W, and with the use of reactive gas mixtures containing CH4 and N2, at the low temperature of 400°C and under pressure of 0.2Tr. The treated surface was analyzed by means of X-ray photoelectron spectroscopy (XPS). The corrosion resistance of the samples was determined on the basis of LSV polarization curves in 3% sodium chloride solution at 37°C. The treated steel surfaces showed a higher tendency for passivation and higher pitting corrosion resistance compared to the non-modified surfaces.
An Analysis of The Influence of Viscosity on The Numerical Simulation of Temperature Distribution, as Demonstrated by the CC Process
Authors: Milkowska-Piszczek K. , Korolczuk-Hejnak M.
Published: January 2014

The numerical modelling of casting processes is based on complex software packages, which most often use the finite element method. But the degree of complexity of the applied model may cause an occurrence of numerical errors. These errors may be generated both by an incorrect finite element mesh and by the use of incorrect material characteristics. The ProCAST numerical software package was used for numerical calculations. A 3D model was developed on the basis of the process parameters of an actual continuous steel casting process. The temperature distribution of a solidifying strand, with dimensions of 220x1100mm, was analysed for two steel grades: F320 and S235. A series of numerical simulations were performed where the influence of the applied viscosity values on the solidifying strand temperature distribution was presented. Viscosity values from rheological examinations that were performed with an FRS1600 high-temperature rheometer were used in the numerical simulations of the CC process. The aforementioned rotational measurements were carried out for the F320 and S235 steels in the liquid and in the semi-solid statesto examine the influence of temperature on the viscosity value changes obtained. A concentric cylinder systems working in accordance with Searle’s method was used for the measurements. Numerical calculations that were based on the viscosity values from the CompuTherm LLC, thermodynamic database were compared with one other in the project. The calculated temperature distribution of the solidifying CC strand was verified on the basis of a database that was created during measurements which were conducted in industrial conditions.
The Results Of Consolidation Of Sinters Being Deformed Under Complex Loading Condition
Authors: Rosiak M.
Published: January 2014

The paper deals with the analysis of the possible application of deformation to sinters under uniaxial compression combined with oscillatory torsion. The main problem of the technology relating to the manufacturing of heavy duty machine components using metal powders is associated with the difficulty to obtain sufficiently high, homogeneously distributed densities across the product volume. The tests were carried out using a test stand allowing the deformation under uniaxial compression combined with torsion. The sintered test specimens were made from the NC 100.24 iron powder. The fabricated sintered test specimens were subject to deformation under the uniaxial compression combined with oscillatory torsion, at three different torsion angle values α = ±30; ±50; ±70 respectively. In order to investigate the effect of different torsion frequencies, each test was made at each torsion angle α for at three different frequencies f = 1 Hz; 0.71Hz; 0.32Hz, respectively, and at the same compression velocity. The results obtained allow to conclude that the application of the combined uniaxial compression and oscillatory torsion (for the preset value of draft) during the tests permitted to obtain the average density of the sinters greater than that obtainable in the case of only unconstrained uniaxial compression. The effect of increased density was enhanced by both the additional torsion-induced deformation, and the tangential stress which would promote the closing of pores.
Evaluation Of The Ml Lute Hypothesis In Respect Of Electrotec Hnical Porcelains
Authors: Ranachowski P. , Rejmund F. , Ranachowski Z. , Pawełek A. , Piątkowski A. , Kudela Jr S.
Published: January 2014

The paper presents the evaluation of the mullite hypothesis explaining the strength of porcelains. There was researched the influence of the mullite phase on the short- and long-term mechanical strength of electrotechnical porcelain of different types (C 110, C 112, C 120 and C 130). The total mullite phase content, the size and distribution of precipitates and dispersed single crystals in the glassy matrix were considered. Mechanoacoustic and microscopic techniques as well as ultrasonic testing were used during the investigation. The role of the mullite phase in the increase of strength and resistance to aging processes of electrical porcelain of various types was described. Mullite hypothesis is valid in reference to siliceous (C 110), cristobalite (C 112) and aluminous C 120 type materials of a typical raw components content and phase composition. In the case of modern strengthened C 120 and C 130 type aluminous materials advantageous are only dispersed fine mullite needles. The precipitates of mullite phase, especially of bigger size, are undesirable.
Modified Ceramic Porous Materials Intended for Retention Viruses Imitating Particles from Water
Authors: Zalewska M. , Szafran M.
Published: January 2014

The main purpose of this study was to perform ceramic composite materials with active filter layers which could be applied in the process of elimination viruses imitating particles from water. In this study, the method of obtaining the active layer on the surface of the ceramic porous materials was developed and simulation of the filtration process using polymer dispersion characterized by similar size of particles to the size of viruses and negative charge at the pH of drinking water as it is in the case of viruses was carried out. In order to obtain ceramic composite materials, two types of zinc oxide were used. Application of ZnO is also beneficial because of their low toxicity to human and antibacterial properties.
Styrene Oxidation by Copper(II) Complexes Salen-Type Encapsulated into Nay Zeolite
Authors: Kuźniarska-Biernacka I. , Carvalho M.A. , Neves I. Correia , Fonseca A. M. , Lisińska-Czekaj A. , Czekaj D.
Published: January 2014

The copper(II) complex with a Schiff-base salen-type ligand has been encapsulated in the nanopores of a NaY zeolite by using two different methodologies, the flexible ligand and in situ complex preparation methods. The encapsulated and non-encapsulated copper(II) complexes were screened as catalysts for styrene oxidation by using TBHP as the oxygen source in acetonitrile solvent. Under the optimized conditions, the catalysts exhibited moderate activity with higher selectivity to benzaldehyde. Both heterogeneous catalysts were found to be reusable after the catalytic cycle, but with some loss of activity
Gelcasting of Alumina with Application of New Monomer Synthesised from Xylitol
Authors: Szudarska A. , Guryniuk D. , Mizerski T. , Szafran M.
Published: January 2014

A new monomer for application in the gelcasting process has been designed and synthesized, following the green chemistry trend to use non toxic and renewable compounds. Xylitol was the main substrate for the synthesis that included 3 stages. The final product, named 1-O-acryloylxylitol, was tested regarding its effectiveness as the processing agent for fabrication of alumina elements by gelcasting method. Rheological properties of the ceramic slurries were studied as well as the properties of shaped elements before and after sintering. The results are compared to those obtained by applying commercial monomer 2-hydroxyethyl acrylate.
Synthesis, Microstructure and the Crystalline Structure of the Barium Titanate Ceramics Doped with Lanthanum
Authors: Wodecka-Duś B. , Plońska M. , Czekaj D.
Published: January 2014

In the present study BaTiO3 and Ba1-xLaxTiO3 (0.1-0.4mol.% La) ceramic powders were synthesized by the conventional mixed oxide method (MOM). The characterization of the ceramic powders was carried out using a simultaneous thermal analysis (STA), with a combined DTA/TG/DTG system (Netzsch STA409). The results of thermal analysis allowed to determine the optimal temperature of synthesis. Microstructure was investigated by scanning electron microscopy (SEM), crystalline structure was studied by X-ray diffraction method (XRD). The EDS investigations showed that samples exhibited conservation of stoichiometry according to the chemical composition formula. The X-ray diffraction analysis confirmed formation of the desired crystalline structure both pure and La3+-doped BaTiO3 ceramics exhibiting a perovskite-type structure ABO3 with tetragonal symmetry P4 mm.
The Effect of Synthesis Parameters on Luminescence Properties of Ca-α-Sialon:Eu2+
Authors: Michalik D. , Sopicka-Lizer M. , Pawlik T. , Lisiecki R.
Published: January 2014

The goal of this study was to investigate influence of the synthesis parameters on the luminescence properties of Ca- α -Sialon doped with Eu2+. The compound of Eu0:07Ca0:73Si9:6Al2:4O0:8N15:2 was prepared by the solid state reaction method from the mixture of the relevant oxides, Si3N4 and CaCO3. Synthesis was carried out in the temperature range of 1600-1700°C for 2-8 h in a reduction atmosphere (N2+CO). The structure and morphology of obtained powders were analyzed by XRD and SEM/EDS methods, respectively. Content of nitrogen/oxygen was also measured. Optical properties were investigated by excitation, emission and reflection spectra. Obtained results show strong influence of synthesis temperature on the phase composition and intensity of emission of Ca- -Sialon:Eu2+ powder compound.
Internal Friction in the Ferroelectric – Ferromagnetic Composites
Authors: Zachariasz R. , Bartkowska J.A. , Bochenek D. , Niemiec P.
Published: January 2014

In the work, temperature Q-1(T) and amplitude Q-1(") dependences of internal friction for ferroelectric - ferromagnetic composites on the base of the PZT and ferrite were determined. The temperature dependences of internal friction Q-1 reveal the peak in the range of high temperatures. We have investigated the peak associated with the viscous-elastic mobility of ferroelectric domain walls. The internal friction due to the viscous-elastic mobility of ferroelectric domain walls was calculated and compared with the experimental data in the reference to the Wang’s theory. Based on internal friction measurements and theoretical considerations, the peak was described. Additionally the amplitude (isothermal) Q-1(") dependences for the composites were made. This allowed for the interpretation of the maximum observed on the temperature dependences of the internal friction Q-1(T).
Study of Properties of Expanded Graphite – Polymer Porous Composite by Acoustic Emission Method
Authors: Berdowski J. , Berdowska S. , Aubry F.
Published: January 2014

The purpose of this paper was to investigate the physical and mechanical properties of compressed expanded graphite (CEG) and their porous derivatives after impregnation, polymerization; and carbonization by the use of acoustic emission method (AE). The mechanical and structural characteristics of compressed expanded graphite and their three groups of porous composites after each technological process are presented and discussed. The measurements of acoustic emission parameters in these materials were carried out at wide range of frequency of the waves (0.1÷2.5 MHz). The changes of two of parameters: - AE pulses counts rate and spectrum distribution of AE waves - are presented in this paper. The analysis of the respective parameters AE also gives possibility to determine the micro- and macro structural changes of materials at different levels of technological processes. Applications of these materials as catalysts with high specific surface make them very interesting subject of study. Also compressed expanded graphite composite membranes prepared from furfuryl alcohol polymers are promising for gas separation.
Composite Ag-La0.6Sr0.4Co0.8Fe0.2O3-δ Cathode Material for Solid Oxide Fuel Cells, Preparation and Characteristic
Authors: Mosialek M. , Tatko M. , Dudek M. , Bielańska E. , Mordarski G.
Published: January 2014

Composite cathodes Ag-La0.6Sr0.4Co0.2Fe0.8O3-δ were obtained by two different procedures. In the first procedure porous La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) matrix was prepared by sintering the LSCF paste, the matrix was then saturated with AgNO3 solution and sintered again. Introduced silver crystalized in the form of 10 nm crystallites in the whole LSCF matrix. In the second procedure the paste of silver powder was deposited on the surface of electrolyte and dried. The layer of silver paste was then covered by a layer of the LSCF paste and sintered at 850°C. The following cells were tested: H2|Ni-Ce0.8Gd0.2O1.9|Ce0.8Sm0.2O1.9 LSCF|O2, H2|Ni-Ce0.8Gd0.2O1.9|Ce0.8Sm0.2O1.9|LSCF-Ag|O2 and H2|Ni-Ce0.8Gd0.2O1.9|Ce0.8Sm-O1.9|Ag|LSCF|O2. Introduction of silver interlayer between cathode and electrolyte increased output power by 18-28% whereas introduction of metallic silver into porous LSCF caused increase in power by 14-18%.
Effects of V2O5 Additive on Structure and Dielectric Properties of BiNbO4 Ceramics
Authors: Lisińska-Czekaj A. , Czekaj D. , Osińska K. , Adamczyk M.
Published: January 2014

Goal of the present research was to investigate the influence of V2O5 additive on the structure and dielectric properties of BiNbO4 ceramics. To fabricate BiNbO4 ceramics with V2O5 added the solid state reaction route and pressureless sintering was utilized. Thus obtained ceramics was characterized in terms of its microstructure (SEM), chemical composition (EDS), phase composition and crystalline structure (X-ray phase and structural analysis, respectively). Also dielectric properties in both temperature and frequency domains were investigated. The impedance spectroscopy was utilized for dielectric characterization and the measurements of complex impedance were performed within the frequency range ν =10Hz-1MHz and temperature range T =RT-550°C. It was found that V2O5 additive changed slightly lattice parameters of BiNbO4 ceramics, decreased porosity of samples and revealled relaxation phenomena within the frequency ranges ν =102-103 Hz and ν =105-106 Hz at temperature T>285°C.
Numerical Simulation of Deformations in T-Joint Welded by the Laser Beam
Authors: Piekarska W. , Kubiak M. , Saternus Z.
Published: January 2014

Numerical simulation of deformations in laser welded T-joint is carried out in this study. The analysis is performed using Abaqus FEA engineering software. Additional author’s numerical subroutines, written in FORTRAN programming language are used in computer simulations where models of the distribution of movable laser beam heat source, kinetics of phase transformations in solid state as well as thermal and structural strain are implemented. Thermomechanical properties of welded material changing with temperature are taken into account in the analysis. Presented results of numerical simulations performed for the laser beam welding of two perpendicularly arranged sheets include temperature distribution, kinetics of phase transformations in solid state, thermal and structural strain as well as estimated welding deformations.
Fabrication of 0.95BaTiO3-0.05Pb(Mg1/3Nb2/3)O3 Ceramics by Conventional Solid State Reaction Method
Authors: Nogas-Cwikiel E. , Suchanicz J.
Published: January 2014

The possibility to obtain of ceramic solid solution between barium titanate and lead magnesium niobate by two-step sintering technique through conventional solid-state reaction method has been investigated. In the first step MgNb2O6 has been synthesized. In the second step 0.95BaTiO3-0.05Pb(Mg1/3Nb2/3)O3 has been obtained using MgNb2O6, PbO and BaTiO3. The two-step sintering technique is effective for the synthesized of 0.95BaTiO3-0.05Pb(Mg1/3Nb2/3)O3 ceramics. Single-phase (pyrochlore-free) ceramics with perovskite phase were obtained.
The Determination of the Magnetoelectric Coupling Coefficient in Ferroelectric–Ferromagnetic Composite Based on PZT–Ferrite
Authors: Bartkowska J.A. , Zachariasz R. , Bochenek D. , Ilczuk J.
Published: January 2014

In the present work, the magnetoelectric coupling coefficient, from the temperature dependences of the dielectric permittivity for the multiferroic composite was determined. The research material was ferroelectric-ferromagnetic composite on the based PZT and ferrite. We investigated the temperature dependences of the dielectric permittivity (") for the different frequency of measurement’s field. From the dielectric measurements we determined the temperature of phase transition from ferroelectric to paraelectric phase. For the theoretical description of the temperature dependence of the dielectric constant, the Hamiltonian of Alcantara, Gehring and Janssen was used. To investigate the dielectric properties of the multiferroic composite this Hamiltonian was expressed under the mean-field approximation. Based on dielectric measurements and theoretical considerations, the values of the magnetoelectric coupling coefficient were specified.
Technology and Properties of Ferroelectromagnetic Lead–Free BFN–Ferrite Composites
Authors: Bochenek D. , Niemiec P.
Published: January 2014

A lead free ceramic composite 0.9BaFe0:5Nb0:5O3-0.1Ni0:5Zn0:5Fe2O4 (BFN-NZF) with ferroelectromagnetic properties have been obtained in presented work. Ceramic composite powder obtained from the simple oxides Fe2O3, Nb2O5, ZnO, NiO and barium carbonate BaCO3. The composition of the composite was chosen so that the ratio of the BFN and NZF components was 90:10. The synthesis of components of BFN-NZF composite was performed using the calcination method. Final densification of synthesized powder has been done using free sintering. The XRD, the microstructure, EDS and dielectric investigations were performed. For comparison of the BFN ceramic and the BFN-NZF composites, temperature and frequency impedance research was conducted. Relaxation phenomena were observed at temperatures above 235°C in the BFN ceramic and above 150°C in the BFN-NZF composite. Obtained results show the coexistence of ferroelectric and magnetic properties. Such properties of obtained composites give the possibility to use them in magnetoelectric transducers.
PROSPECTION FOR COPPER MINERALIZATION WITH CONTRIBUTION OF REMOTE SENSING, GEOCHEMICAL AND MINERALOGRAPHICAL DATA IN ABHAR 1:100,000 SHEET, NW IRAN / POSZUKIWANIA ZASOBÓW RUD MIEDZI Z ZASTOSOWANIEM ZDALNYCH TECHNIK WYKORZYSTUJĄCYCH DANE GEOCHEMICZNE I MINERALOGICZNE W POKŁADZIE GEOLOGICZNYM ABHAR 1:100,000 W PÓŁNOCNO-ZACHODNIM IRANIE
Authors: Nouri Reza , Jafari Mohammadreza , Arian Mehran , Feizi Faranak , Afzal Peyman
Published: January 2014

Abhar 1:100,000 sheet is located within the Cenozoic Tarom volcano-plutonic belt, NW Iran. The present study is based on the integration of remote sensing techniques on Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), geochemical data analysis consisting of stream sediment and lithogeochemical samples, within geological field observations and mineralographical studies to identify Cu prospect. On ASTER data; using a number of selected methods including band ratio, Least Square Fit (LS-Fit) and Minimum Noise Fraction (MNF) distinguished alternation zones. These methods revealed that three types of alterations: argillic, phyllic, and iron oxide zones occurring at the NE and SE of Abhar sheet, while the propylitic and silica zones are developed in NW and SW of the studied area. Lineaments were identified by aid of false color composite, high pass filters and hill-shade DEM techniques that two NW-SE and NE-SW major trends were determined. Geochemical anomalies were separated by number-size (N-S) method. Interpretation of N-S log-log plots of Cu in the area may be a result of the three steps of enrichment, i.e., mineralization and later dispersions. Field checks and Mineralgraphical studies also confirm the existence of suitable copper mineralization.
PROGNOSTIC ACCUMULATION ZONES FOR OIL AND NATURAL GAS IN THE CRITERIA FOR THE DISTRIBUTION OF PETROPHYSICAL PARAMETERS IN THE MAIN DOLOMITE IN GORZOW-PNIEWY AREA / PROGNOSTYCZNE STREFY AKUMULACJI DLA ROPY NAFTOWEJ I GAZU ZIEMNEGO W KRYTERIACH ROZKŁADU PARAMETRÓW PETROFIZYCZNYCH DOLOMITU GŁÓWNEGO W OBSZARZE GORZÓW-PNIEWY
Authors: Semyrka Roman , Maruta Michał , Pasternacki Andrzej
Published: January 2014

The carbonate reservoirs are anisotropic environments in terms of both the quantitative and qualitative evaluations of pore space. The oil-and-gas-bearing Main Dolomite horizon shows diversified lithology, facial development and thickness resulting in complicated, fluid capacity-fluid filtration system. This system influences both the evaluation and exploration perspectives in the Zechstein Main Dolomite (Ca2) from the Gorzów-Pniewy area. In order to clarify this problem and to determine the hydrocarbon accumulation perspectives, analysis of petrophysical parameters based upon the porosimetric measurements was carried on for the Main Dolomite in the study area, where oil and gas accumulations were discovered. The results of porosimetric measurements clearly indicate the heterogeneity of petrophysical parameters of the Main Dolomite referred to lithologically diversified palaeogeographic zones distinguished in the study area. Such analysis, including the hydrocarbon storage capacity of the Main Dolomite, enabled us to evaluate the possible hydrocarbon accumulation related to generation potential of this horizon.
CONDITION MONITORING OF OFF-HIGHWAY TRUCK TIRES AT SUNGUN COPPER MINE USING NEURAL NETWORKS / MONITOROWANIE STANU TECHNICZNEGO OPON W CIĘŻKICH POJAZDACH TERENOWYCH EKSPLOATOWANYCH W KOPALNI MIEDZI SUNGUN, PRZY UŻYCIU SIECI NEURONOWYCH
Authors: Morad Amin Moniri , Sattarvand Javad
Published: January 2014

Maintenance cost of the equipment is one of the most important portions of the operating expenditures in mines; therefore, any change in the equipment productivity can lead to major changes in the unit cost of the production. This clearly shows the importance and necessity of using novel maintenance methods instead of traditional approaches, in order to reach the minimum sudden occurrence of the equipment failure. For instance, the tires are costly components in maintenance which should be regularly inspected and replaced among different axles. The paper investigates the current condition of equipment tires at Sungun Copper Mine and uses neural networks to estimate the wear of the tires. The Input parameters of the network composed of initial tread depth, time of inspection and consumed tread depth by the time of inspection. The output of the network is considered as the residual service time ratio of the tires. The network trained by the feed-forward back propagation learning algorithm. Results revealed a good coincidence between the real and estimated values as 96.6% of correlation coefficient. Hence, better decisions could be made about the tires to reduce the sudden failures and equipment breakdowns.