Swieszkowski W.,Warsaw University of Technology |
Jaegermann Z.,Institute of Glass |
Hutmacher D.W.,National University of Singapore |
Hutmacher D.W.,Queensland University of Technology |
Kurzydlowski K.J.,Warsaw University of Technology
Ceramic Transactions | Year: 2010
The aim of this study is to show how ceramic materials could be used in bone tissue replacement and regeneration. The possibility of treatment of bone defects using porous alumina grafts, calcite porous scaffolds, polymer/ceramic biocomposite scaffolds and ceramic coatings will be shown. Physical properties as well as architecture of the porous structure of porous alumina bone grafts formed by gel casting will be described. The long term clinical results of using porous alumina implants will be presented. The calcite based porous ceramics will be discussed as a material for bone regeneration. The influence of chemical compositions and sintering parameters on the physical properties of sintered calcite ceramics as well as forming of porous material by polymeric sponge method will be shortly described. A novel material made of biodegradable polymer reinforced with modified calcium phosphates (TCP) particles will be proposed to be used in fabrication of novel constructs for the repair of critical-sized bone defects. Several composite materials made of PLLA/PDLA or PCL reinforced with TCP micro and nanoparticles will be discussed. To make the metallic implants more osteogenic, hydroxyapatite or TiO2 coatings might be applied. The different methods of coating of the porous and non porous titanium implants with ceramic layers will be described.
Bulkowski L.,Polish Institute for Ferrous Metallurgy |
Galisz U.,Polish Institute for Ferrous Metallurgy |
Kania H.,Polish Institute for Ferrous Metallurgy |
Kudlinski Z.,Silesian University of Technology |
And 2 more authors.
Archives of Metallurgy and Materials | Year: 2012
The concerned paper presents results of wide scope of liquid steel filtering tests by means of ceramic filters, including laboratory, model and industrial testing in the conditions of conventional (ingot) and continuous steel casting. Multi-hole (sieve) ceramic filters made of mullite and corundum, of the structure adjusted to the type of conducted experiment were used for testing. Selection of ceramic material for filter construction accounted for the conditions of filter operations including: high temperature (liquid steel temperature), filtering duration determined by mass of the filtered steel, hydrodynamics of steel flow through filter holes an and wettablity of filter ceramics by non-metallic inclusions. In order to assess the effectiveness of liquid steel filtering in reference to unfiltered steel, the following criteria have been adopted:-change in surface share of non-metallic inclusions,-change in the quantity of non-metallic inclusions and dimensions thereof,-change in total oxygen content (summary).The obtained results of tests confirm high effectiveness of liquid steel filtering by means of ceramic filters and may constitute a basis for development of a new technology of steel refining by means of filtration.
Saramak D.,AGH University of Science and Technology |
Naziemiec Z.,Institute of Glass
Physicochemical Problems of Mineral Processing | Year: 2013
A proposal of the nip zone angle determination in high-pressure grinding rolls (HPGR) crushing process is presented in the paper. Knowledge of the nip zone angle value makes it possible to determine the real maximum pressing force in the high-pressure comminution. Two methods of determination of this maximum pressure were proposed and verified. The first method is based on the roll's geometry and the change of the HPGR chamber's volume together with the roll rotation, while the second one considers the outlet gap width. Results of the nip zone angle calculations according to both methods are similar and show that the nip zone angle is around 3°. The verification was carried out in a piston-die press and experimental results show that the product size distributions from HPGR and piston-die press are similar. The methodology of the nip zone angle determination presented in the paper has then its practical confirmation. A proper determination of the nip zone border makes it possible to calculate the comminution probability of given type of material and is a basis for the HPGR crushing process modeling and optimization.
Saramak D.,AGH University of Science and Technology |
Naziemiec Z.,Institute of Glass
26th International Mineral Processing Congress, IMPC 2012: Innovative Processing for Sustainable Growth - Conference Proceedings | Year: 2012
The proposal of the nip zone angle determination in HPGR crushing process is presented in the paper. Knowledge of the nip zone angle value, in turn, makes it possible to determine the real maximum pressing force in the high-pressure comminution. Two methods of determination of this maximum pressure were proposed and verified. The first method is based on the roll's geometry, and the change of the HPGR chamber's volume together with the roll rotation, while the second one considers the outlet gap width impact. Results of the nip zone angle calculations according to both methods are similar and show convergence with the real operating conditions. The verification was carried out in a piston-die press, and experimental results show that methodology of the nip zone angle determination presented in the paper has its practical confirmation. A proper determination of the nip zone border makes it possible to calculate the comminution probability of given type of material and is a basis for the HPGR crushing process modeling and optimization.
Zelazowska E.,Institute of Glass |
Rysiakiewicz-Pasek E.,Wroclaw University of Technology
Optica Applicata | Year: 2010
Sol - gel derived lithium-ion conducting organic - inorganic hybrid materials have been synthesized from tetraethyl orthosilicate (TEOS), propylene glycol, ethylene glycol dimethacrylate, poly(vinyl alcohol), vinyl acetate, ethyl acetoacetate, poly(methyl methacrylate), propylene carbonate and some other precursors and solvents. The mass fraction of the organic additions in the gels and the level of the lithium salt doping (LiClO4) were ~40 mass% and 0.01%, respectively. The morphological and structural properties of the gels were investigated by a scanning electron microscope equipped with energy dispersive X-ray spectroscopy (SEM/EDX), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR) and29Si MAS Nuclear Magnetic Resonance (29Si MAS NMR). The hybrid gels obtained were amorphous and colourless transparent or slightly opalescent, with the room temperature ionic conductivities of the order of 10-3 Scm -1. The results of FTIR spectroscopy and29Si MAS NMR investigations have revealed strong influence of the organic modification, resulting in the direct chemical bonding between organic and inorganic components of the gels. The WO3-based electrochromic cells with the hybrids obtained being applied as the electrolytes were able to be reversibly coloured and bleached in the optical transmittance range of ~58% to 5% at around 550 nm.
Podworny J.,Institute of Glass |
Zawada J.,Institute of Glass
Solid State Phenomena | Year: 2010
The paper presents results of investigations aimed at determining the structure of lowtemperature tridymite in refractory silica materials. In the initial phase of works, the literature and Internet databases containing structural data of crystalline compounds were reviewed in search of a model of tridymite structure which best fits the one forming in silica materials. The results of reviewing the models of polymorphous tridymite forms which are available in the world literature have been verified by Rietveld method, using a sample of silica material that contained tridymite without cristobalite and residual quartz. On the basis of analyses it was found that tridymite in refractory silica materials occurs in a form of two low-temperature polymorphous forms C1 and F1, instead of one form-Cc, as it was assumed before. The developed model has been used in a quantitative analysis (Rietvield method) of phase composition of several silica refractories.
Konieczynski J.,Polish Academy of Sciences |
Stec K.,Institute of Glass
Archives of Environmental Protection | Year: 2010
The emission of dust from coal fired furnaces introduces a lot of contamination into the environment, including dangerous metal compounds, which occur as trace elements in hard and brown coal. After the coal is burnt, they are contained in the grains of respirable dust, which creates health hazard. The results of investiga tions into the distribution of several trace elements in granular composition of ash emitted from CFB boilers used in coal-fired heat and power station are presented. The research material was taken by means of a cascade impactor, enabling a different granulometric fraction to be separated from a stream of dust that penetrated the electrofilter. The ICP-AES method (inductively coupled plasma atomic emission spectroscopy) was used to determine trace elements after prior mineralization of samples by microwave method. The Authors presented the results of measurements and analyses, determining the ranges of trace elements' occurrence in dust, charac terizing the distribution in PM1, PM25 and PM10 granulometric fractions and determining the emission factors. © Copyright by Institute of Envionmental Engineering of the Polish Academy of Sciences, Zabrze, Poland 2010.