Search results for "Zirconium dioxide"
showing 10 items of 10 documents
Extraction and immediate placement of root analogue zirconia implants: an overview
2011
Dental implants constitute a well-established approach for replacement of lost teeth with titanium being the most favored material for implantation. However, titanium has its limitations in esthetically demanding cases and neither the form nor material of such implants has changed much over the past 40 years. Immediate implantation has been introduced to overcome the disadvantages of conventional implantation which in turn has many disadvantages owing to the incongruence of the implant to the extraction socket. Today, there is scientific evidence that zirconia dental implants osseointegrate well and offer many advantages over titanium implants. The successful use of zirconia ceramics in ort…
Zirconium dioxide implants as an alternative to titanium: A systematic review
2020
Background: This systematic review evaluates the available scientific literature to demonstrate the aesthetic and clinical benefits and to determine the survival and the success of zirconium dioxide implants concerning titanium implants. Material and Methods: The electronic databases were searched until January 2020. Outcome measures were pink aesthetic score (PAS), white aesthetic score (WAS), bleeding on probing (BOP) and probing depth (PD). The addressed PICO question was: In partially edentulous patients in the upper-anterior sector, do zirconium dioxide implants provide aesthetic benefits over conventional titanium implants? Results: In the 15 articles included after the screening were…
Phase stability and oxygen-sensitive photoluminescence of ZrO2:Eu,Nb nanopowders
2018
This work was supported by institutional research funding ( IUT34-27 and IUT2-14 ) of the Estonian Ministry of Education and Research .
Structure formation and properties of corundum ceramics based on metastable aluminium oxide doped with stabilized zirconium dioxide
2021
Abstract The work presents a successful example of the use of YSZ binary systems for production of composite ceramic materials based on θ-Al2O3 with improved physical and mechanical characteristics which was previously considered an unpromising material. It was first obtained result of extreme nature of dependence of physical and mechanical properties of Al2O3+YSZ on the concentration of YSZ (ZrO2–3mol% of Y2O3) additive. The sintering temperature was decreased on 250 °C (from 1800 to 1550 °C). The phase composition of powders and the structure of ceramics of the Al2O3 + YSZ system were investigated depending on the amount of YSZ dopant, the structure-properties relationship was established…
Stochastic resonance in a metal-oxide memristive device
2021
Abstract The stochastic resonance phenomenon has been studied experimentally and theoretically for a state-of-art metal-oxide memristive device based on yttria-stabilized zirconium dioxide and tantalum pentoxide, which exhibits bipolar filamentary resistive switching of anionic type. The effect of white Gaussian noise superimposed on the sub-threshold sinusoidal driving signal is analyzed through the time series statistics of the resistive switching parameters, the spectral response to a periodic perturbation and the signal-to-noise ratio at the output of the nonlinear system. The stabilized resistive switching and the increased memristance response are revealed in the observed regularities…
Comparative X-ray diffraction study of the crystalline microstructure of tetragonal and monoclinic vanadium–zirconium dioxide solid solutions produce…
2009
The microstructural characteristics of solid solutions, prepared by heating dried gel precursors with nominal compositions VxZr1−xO2(0 ≤x≤ 0.1) at 723 and 1573 K, were determined from X-ray diffraction patterns. The crystalline microstructure of the resulting specimens, characterized by a prevalent crystallite shape, a volume-weighted crystallite size distribution and a second-order lattice strain distribution, was found to depend on the vanadium content. A characteristic feature of all size distributions was their bimodality, explained as a result of transformations between tetragonal and monoclinic phases during thermal treatment. A comparative study of the microstructure of both zirconia…
Structural Infrared Analysis of Ultra Nanosized Crystals of Yttria-Stabilized Zirconia
2017
This paper describes the characterization of ultra nanosized crystals as monoclinic, tetragonal, cubic or mixed phases of ZrO2. Nanopowders are produced using the microwave method, which allows control of the ratio of zirconium to yttrium to yield various crystallographic structures. The synthesized ultra nanosized particles have very broad XRD peaks. In particular, the similarity of the XRD peaks of tetragonal and cubic nanocrystals makes it difficult to distinguish between these two crystals. In this paper, tetragonal and cubic nanocrystals were clearly distinguished using infrared spectroscopy (IR). An infrared spectroscopic method to quantitatively analyse the percentage distribution be…
A Study of Osmosis Rate Through Several Proton Conducting Polymer Composite Membranes
2021
Carbon dioxide is typically considered to be a byproduct of various industrial processes that should not be released into the environment due to its nature as a harmful greenhouse gas. One of the more promising ways to dispose of it in an economical and environmentally friendly way is by using it as a raw material in electrochemical synthesis reactors. An important part of such reactors is an ion exchange membrane. In this study the influence of ZrO2 content in SPEEK – ZrO2 composite membranes on rate of osmosis trough them was investigated, with the goal of evaluating ZrO2 as an additive for making ion exchange membranes with fine-tuned osmotic permeability.
DFT Prediction of Enhanced Reducibility of Monoclinic Zirconia upon Rhodium Deposition.
2018
Oxides are an important class of materials and are widely used, for example, as supports in heterogeneous catalysis. In a number of industrial catalytic processes, oxide supports actively participate in chemical transformations by releasing lattice oxygen anions. While this is intuitively understood for reducible oxides, the reducibility of irreducible oxides may be modified via nanoengineering or upon inclusion of foreign species. Our calculations predict that the ability of irreducible monoclinic zirconia to release oxygen improves substantially upon deposition of rhodium. Through a comprehensive screening of Rh/ZrO2 with different size of the rhodium species, we find that a Rh adatom and…
Paramagnetic Defects and Thermoluminescence in Irradiated Nanostructured Monoclinic Zirconium Dioxide
2022
The work was carried out under the grant of the Ministry of Education and Science of the Republic of Kazakhstan AP09260057, “Luminescence and radiation resistance of synthesized under different conditions micro- and nanostructured compacts and ceramics based on ZrO2”. The research was partly (A.I.P.) performed at the Center of Excellence of the Institute of Solid State Physics, University of Latvia, supported through European Union Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2, under grant agreement No. 739508, project CAMART2.