Wyszukiwarka
Filtry
wszystkich: 118
wybranych: 82
Wyniki wyszukiwania dla: metallurgy
-
Styrene epoxidation over heterogeneous manganese(III) complexes
PublikacjaThe manganes(III) complex functionalised with 2,3-dihydropyridazine has been encapsulated in the supercages of the NaY zeolite using two different procedures, flexible ligand and in situ complex. The parent zeolite and the encapsulated manganese(III) complexes were screened as catalysts for styrene oxidation by using t-BOOH as the oxygen source in acetonitrile. Under the optimized conditions, the catalysts exhibited moderate activity...
-
Influence of Processing Conditions on Crystal Structure of Bi6Fe2Ti3O18 Ceramics
PublikacjaAim of the present research was to apply a solid state reaction route to fabricate Aurivillius-type ceramics described with the formula Bi6Fe2Ti3O18 (BFTO) and reveal the influence of processing conditions on its crystal structure. Pressureless sintering in ambient air was employed and the sintering temperatures were 850 and 1080 °C. It was found that the fabricated BFTO ceramics were multiphase ones. They consisted of two Bim+1Fem-3Ti3O3m+3...
-
Effects of V2O5 Additive on Structure and Dielectric Properties of BiNbO4 Ceramics
PublikacjaGoal 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...
-
Study of Phase and Chemical Composition of Bi1-xNdxFeO3 Powders Derived by Pressureless Sintering
PublikacjaIn the present paper studies on Bi1xNdxFeO3 for x =0.1-0.4 are reported. The mixed oxide method followed with pressureless sintering was employed for ceramics fabrication. Thermal behavior of stoichiometric mixtures of simple oxide powders, viz. Bi2O3, Nd2O3 and Fe2O3 was studied by simultaneous thermal analysis. It was found that with an increase in neodymium content the weight loss increased from 0.75% to 3.16% for x =0.1 and...
-
Effect of Bi2O3 Excess on Morphology and Structure of BiNbO4 Ceramics
PublikacjaGoal of the present research was to fabricate BiNbO4 ceramics from the mixture of powders by the solid state reaction route and pressureless sintering at various temperatures (TS =8700C and TS =9100C) and study microstructure, phase composition and crystalline structure of BiNbO4 ceramics. Four batches were fabricated and examined, namely the one fabricated from the stoichiometric mixture of reagent – grade oxide powders, viz....
-
A New Microwave Ceramic – Polymer Composite with 0-3 Connectivity
PublikacjaGoal of the present research was to fabricate and study two-phase BiNbO4//PVDF composites with 0-3 connectivity. Such composite consists of there-dimensionally connected polymer matrix loaded with dielectric ceramic particles. In the present case BiNbO4 powder acted as an active phase (dispersed phase) whereas polyvinylidene fluoride (PVDF) acted as a non-active (passive) phase (matrix). BiNbO4//PVDF composites with the volume...
-
INFLUENCE OF BISMUTH CONTENT ON COMPLEX IMMITTANCE CHARACTERISTICS OF PRESSURELESS SINTERED BiNbO4 CERAMICS
PublikacjaGoal of the present research was to study immittance properties of BiNbO4 ceramics fabricated by the solid state reaction route followed by pressureless sintering. Four sets of samples were examined, namely the one fabricated from the stoichiometric mixture of oxides, viz. Bi2O3 and Nb2O5 as well as the ones with an excess of 3%, 5% and 10% by mole of Bi2O3. The immittance properties were studied by impedance spectroscopy. Measurements...
-
Styrene Oxidation by Copper(II) Complexes Salen-Type Encapsulated into Nay Zeolite
PublikacjaThe 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...
-
The Impact of Crushed Rock Spoil on Pitting Corrosion of Selected Stainless Steel
PublikacjaThe paper presents the results of the pitting resistance investigations of selected stainless steels in the chloride environment and the simultaneous impact of erosive factors using the cyclic polarization technique. Additionally, using electrochemical techniques, ie: electrochemical impedance spectroscopy (EIS) and measurement of corrosion potential, the behavior of the passive layer of selected stainless steels in the environment...
-
Effect of Semiconductor Element Substitution on the Electric Properties of Barium Titanate Ceramics
PublikacjaThe investigated ceramics were prepared by a solid-state reaction from simple oxides and carbonates with the use of a mixed oxide method (MOM). The morphology of BaTi0.96Si0.04O3 (BTSi04) ceramics was characterised by means of a scanning electron microscopy (SEM). It was found that Si+4 ion substitution supported the grain growth process in BT-based ceramics. The EDS results confirmed the high purity and expected quantitative composition...
-
Analysis of the amount of retained austenite in the structure of steel rolls for sheet rolling
Publikacja -
A review on the critical challenges and progress of SiOx-based anodes for lithium-ion batteries
Publikacja -
Effect of Thermal Treatment at Inert Atmosphere on Structural and Magnetic Properties of Non-stoichiometric Zinc Ferrite Nanoparticles
Publikacja -
In Vitro and Ex Vivo Chemical Stability Studies of Layers on Substrates and Implants Made of Titanium Alloy
Publikacja -
On the Possibility of Improving the Oxidation Resistance of High-Chromium Ferritic Stainless Steel Using Reactive Element Oxide Nanoparticles
PublikacjaHigh-chromium ferritic steels are current the only viable candidates for cheap interconnect materials for application in high-temperature solid oxide fuel and electrolyzer cells (HT-SOFCs/SOECs). The durability and operating characteristics of interconnects manufactured using these materials may be improved significantly by applying a protective-conducting MoCo2O4 coating and depositing an intermediate layer consisting of nanoparticles...
-
Analysis of Residual Stresses and Dislocation Density of AA6082 Butt Welds Produced by Friction Sir Welding
PublikacjaThe Friction Stir Welding (FSW) method was employed to join AA6082 sheets. The welds were produced with different tool traverse speed (200 and 250 mm/min), rotational speed (1000 and 1250 RPM) and tool tilt angle (0 and 2 deg). Based on the analysis of XRD patterns, the total precipitation volume fractions in the nugget zones and the base material were calculated. The FSW process resulted in a reduction in the fraction of precipitates...
-
High-temperature Corrosion of ~ 30 Pct Porous FeCr Stainless Steels in Air: Long-Term Evaluation Up to Breakaway
PublikacjaIn this work, a long-term (up to 6000 hours) corrosion evaluation of three porous (~ 30 pct of initial porosity) ferritic iron-chromium alloys with different Cr contents (20, 22, and 27 wt pct of Cr) was carried out at 600 C, 700 C, 800 C, and 900 C in air. Mass gain measurements and SEM analyses revealed that at temperatures above 600 C, all alloys exhibit breakaway corrosion, whereas at 600 C, none of the alloys were heavily...
-
Study on Microstructure-Property Relationship of Inconel 617 Alloy/304L SS Steel Dissimilar Welds Joint
PublikacjaWelding of Inconel 617 (IN617) alloy and austenitic 304L SS steel has been attempted using the autogenous Laser Beam Welding (LBW) process. Characterization of dissimilar weldments was performed on either side of the fusion boundaries. The metallographic results showed that the inhomogeneous microstructure formation for weld metal contained columnar and cellular dendrites near the interface, whilst the columnar, cellular and equiaxed...
-
TiO2 and Reducing Gas: Intricate Relationships to Direct Reduction of Iron Oxide Pellets
PublikacjaIn response to the imperative for sustainable iron production with reduced CO2 emissions, this study delves into the intricate role of TiO2 in the direct reduction of iron oxide pellets. The TiO2-dependent reducibility of iron oxide pellets utilizing H2 and CO gas across varied temperatures and gas compositions is thoroughly investigated. Our findings unveil the nuanced nature of the TiO2 effect, underscored by its concentration-dependent...
-
Formation of Porous Structure of the Metallic Materials Used on Bone Implants
PublikacjaResearch on improvement of structure and fabrication methods of the bone implants are carried out for many years. Research are aimed to shape the structures, that will have a Young's modulus value similar to the value of the human bones Young's modulus. Depending on theporosity, Young's moduli can even be tailored to match the modulus of bone closer than solid metals can, thus reducing the problems associated with stress shielding...
-
Coatings in arthroplasty [online]
PublikacjaThe modern coatings used in arthroplasty for long term implants are reviewed. The phosphate coatingsare the most popular technique to improve the bone-implant interfacial strength and promote theosseointegration. The plasma spraying, electrophoretic precipitation, powder metallurgy, ion beamsputtering, high velocity oxy-fuel (HVOF) combustion spraying, sol-gel technique, biomimeticdeposition are mostly used to obtain the phosphate,...
-
Experimental and numerical studies on the mechanical response of a piezoelectric nanocomposite-based functionally graded materials
PublikacjaThis work presents an experimental study of piezoelectric structures reinforced by graphene platelets, based on the concept of the functionally graded materials (FGMs). The assumed model is a rectangular beam/plate and the composition is due to the Halpin-Tsai rule. The model is also simulated in the Abaqus software which is the first time that such a structure has been modelled in an FEM package. In addition, a mathematical model...
-
A Quantitative Investigation of Dislocation Density in an Al Matrix Composite Produced by a Combination of Micro-/Macro-Rolling
PublikacjaAn aluminum matrix composite with dispersed carbon nanotubes (CNTs) was produced via flake powder metallurgy using a micro-rolling process and vacuum hot pressing (VHP), followed by conventional rolling using a macro-rolling process. The microstructure and mechanical properties of the produced composites were studied. In addition, a new quantitative model was introduced to study the dislocation density based on the microstructural...
-
Annual changes of basic parameters of bottom sediments from the Klodnica River Catchment
PublikacjaThe Klodnica River Catchment is heavily contaminated ecosystem located in area of the Upper Silesia Industrial Region. In this area various forms of human activity can be observed (e.g. mining coal underground, metallurgy, power/heat plants, wastewater discharged directly into the river). The impact of industrial and municipal wastes on this aquatic system causes to changes in the hydrographic network of river and the waters quality. In...
-
Biocompatibility and bioactivity of load-bearing metallic implants
PublikacjaThe main objective of here presented research is to develop the titanium (Ti) alloy base composite materials possessing better biocompatibility, longer lifetime and bioactivity behaviour for load-bearing implants, e.g. hip joint and knee joint endoprosthesis. The development of such materials is performed through: modeling the material behaviour in biological environment in long time and developing of new procedures for such evaluation;...
-
Materials Design for the Titanium Scaffold Based Implant
PublikacjaThe main objective of here presented research is a design the scaffold/porous titanium(Ti) alloy based composite material demonstrating better biocompatibility, longer lifetime andbioactivity behaviour for load-bearing implants. The development of such material is proposed bymaking a number of consecutive tasks. Modelling the mechanical, biomechanical and biologicalbehavior of porous titanium structure and an elaboration of results...
-
Materials Design for the Titanium Scaffold Based Implant
PublikacjaThe main objective of here presented research is a design the scaffold/porous titanium(Ti) alloy based composite material demonstrating better biocompatibility, longer lifetime andbioactivity behaviour for load-bearing implants. The development of such material is proposed bymaking a number of consecutive tasks. Modelling the mechanical, biomechanical and biologicalbehavior of porous titanium structure and an elaboration of results...
-
Monitoring strategy for industrially contaminated rivers - A study of all year round behaviour of Klodnica river catchment, upper Silesia, Poland
PublikacjaThe study was undertaken to thoroughly characterise the contamination of water in industrially influenced river Klodnica, in order to explore monitoring strategies in case of limited analytical capacity. Statistical analysis undertaken after a short study was found to be helpful in reducing monitoring efforts in the future.Klodnica river is located within area of dominating coal mining, metallurgy, and additionally being influenced...
-
Reducing Monitoring Costs in Industrially Contaminated Rivers: Cluster and Regression Analysis Approach
PublikacjaMonitoring contamination in river water is an expensive procedure, particularly for developing countries where pollution is a significant problem. This study was conducted to provide a pollution monitoring strategy that reduces the cost of laboratory analysis. The new monitoring strategy was designed as a result of cluster and regression analysis on field data collected from an industrially influenced river. Pollution sources in...
-
Selected anionic and cationic surface active agents: case study on the Kłodnica sediments
PublikacjaSurface active agents (surfactants) are a group of chemical compounds, which are used as ingredients of detergents, cleaning products, cosmetics and functional products. After use, wastes containing surfactants or their degradation products are discharged to wastewater treatment plants or directly into surface waters. Due to their specific properties of SAAs, compounds are able to migrate between different environmental compartments...
-
Exploring hydrogen energy systems: A comprehensive review of technologies, applications, prevailing trends, and associated challenges
PublikacjaExploring hydrogen energy and its associated technologies is a pivotal pathway towards achieving carbon neutrality. This article comprehensively reviews hydrogen production technologies, storage technologies, and end-use applications of hydrogen, based on the input energy source, operating conditions, conversion efficiency, energy density, and unit investment cost. The review also highlights the advantages, disadvantages, and technological readiness...
-
Comparison of heat transfer characteristics in surface cooling using microjets with water, ethanol and HFE7100 as test fluids
PublikacjaAccurate control of cooling parameters is required in ever wider range of technical applications. It is known that reducing the dimensions of the size of nozzle leads to an increase in the economy of cooling and improves its quality. Present study describes research related to the design and construction of the nozzles and microjet study, which may be applied in many technical applications such as in metallurgy, electronics, etc....