Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "Sol-gel" wg kryterium: Temat

  Lista filtrów
Wyrównaj
Wyświetlanie 1-15 z 17
Tytuł:
Mechanical properties and cell viability of MgO-reinforced biografts fabricated for biomedical applications
Autorzy:
Demirel, M.
Powiązania:
https://bibliotekanauki.pl/articles/306588.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
MgO
sol-gel
biograft
cytotoksyczność
sol–gel
cytotoxicity
Opis:
In the present study, biografts were produced by sol gel method by adding different rates of MgO which has bone-like crystal structure and high endurance into different proportions of Ca(NO3)24H2O, KOH, NaNO3, and P2O5 compounds. The biografts were investigated in terms of mechanical and biocompatibility properties. FTIR, SEM and XRD analyses were carried out to examine the chemical characteristics and changes in structural morphology. Mechanical properties were also investigated by conducting hardness and compression tests. In addition, cytotoxicity tests were conducted by using osteoblast cells. While results of FTIR and XRD analyses revealed that all biografts had HA (hydroxyapatite) and β-TCP contents, MgO peaks were also observed in biografts. In SEM images, grains of NonMgO and MgO-10 biografts had sharper edges, pores formed between grains and grain size increase with increasing MgO amount (MgO-20 and MgO-30). It was found that compression stress and hardness values increased as MgO content elevated. From the cytotoxicity tests, no any toxic effect was observed in the syntesized biografts.
Źródło:
Acta of Bioengineering and Biomechanics; 2018, 20, 4; 83-90
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chemical resistance of SiO2 layers obtained by the sol–gel technique on a glass substrate
Autorzy:
Nocuń, M
Środa, M
Ciecińska, M
Powiązania:
https://bibliotekanauki.pl/articles/173238.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
sol-gel
antireflection coating
sintering parameters
Opis:
The paper analyses the influence of heat treatment parameters on SiO2 coatings obtained by the sol–gel technique. Their adhesion to the glass substrate and corrosion resistance were studied. The changes in thickness and porosity with the firing temperature and time of sintering for the systems of 1, 2 and 3 layers in case of SiO2 layers were studied. It was shown that the sufficient durability of the SiO2 coating on the glass substrate can be achieved only by the appropriate selection of thermal treatment parameters. The results confirmed that higher sintering temperature is required for multilayer systems, as compared with a one-layer system.
Źródło:
Optica Applicata; 2015, 45, 1; 125-134
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on the activity of ZnO-SnO2 nanocomposite against bacteria and fungi
Autorzy:
Omar, K.
Meena, B. I.
Muhammed, S. A.
Powiązania:
https://bibliotekanauki.pl/articles/109343.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
ZnO-SnO2 nanocomposite
bacteria
fungi
sol-gel method
Opis:
ZnO-SnO2 nanocomposite was prepared by the sol-gel method. The as-prepared nanocomposite was characterized by X-ray diffraction (XRD), scanning electron micrograph (SEM-EDX), FTIR and UV-Visible spectrometer analysis techniques. The average particle size of nanocomposite was calculated from the XRD study. The average particle size of the prepared nanocomposite was 22 nm. According to the UV-Visible spectrum, the band gap value of 5.06 eV was obtained for the ZnO-SnO2nanocomposite. From the analysis techniques it was found that the metal oxides of ZnO-SnO2 mainly consist of ZnO and SnO2 metal oxides. The antibacterial and antifungal activities of the ZnO-SnO2nanocomposite were studied against Staphylococcus aureus (ATCC25923), Listeria monocytogenes (ATCC 11994)(Gram-positive), Salmonella typhi (ATCC14028), Escherichia coli (ATCC 25922)Gram-negative), Candida albicans (ATCC10231), and Aspergillus niger (ATCC 16404) (fungi)by two methods through the turbidity method or reading optical density and inhibition zone, which were carried out in the absence of irradiation. We observed an effective antibacterial and antifungal activity of the ZnO-SnO2 nanocomposite against bacteria and fungi.
Źródło:
Physicochemical Problems of Mineral Processing; 2016, 52, 2; 754-766
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fabrication of fluoride nanocrystals and their spectroscopic properties
Autorzy:
Pawlik, N.
Szpikowska-Sroka, B.
Goryczka, T.
Pisarski, W. A.
Powiązania:
https://bibliotekanauki.pl/articles/173278.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
sol-gel method
glass-ceramics
fluoride nanocrystals
europium ions
Opis:
In this work, the fabrication of glass-ceramic materials containing MF3:Eu3++ (M = La, Gd) nanocrystals dispersed in silica sol-gel hosts has been presented. The transformation from liquid sols towards bulk samples was also examined based on IR measurements. The crystallization temperatures and formation of MF3 phases were verified based on TG/DSC analysis and XRD measurements. The optical properties of prepared Eu3+5D05D0 → 7FJ (J = 1–4) emission bands, which were recorded within the reddish-orange spectral area under near-UV illumination (λexc = 393 nm). Recorded luminescence spectra and double-exponential character of decay curves for prepared glass-ceramic samples indicated the successful migration of Eu3+ dopant ions from amorphous silica framework to low-phonon energy MF3 nanocrystal phases.
Źródło:
Optica Applicata; 2019, 49, 3; 415-426
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Surface properties of the doped silica hydrophobic coatings deposited on plasma activated glass supports
Autorzy:
Chodkowski, Michał
Terpiłowski, Konrad
Goncharuk, Olena
Powiązania:
https://bibliotekanauki.pl/articles/110289.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
hydrophobicity
surface chemistry
glass
silica
sol-gel method
immersion
plasma
Opis:
The paper discusses preparation and characteristics of silica hydrophobic layers deposited on the plasma-modified glass supports. The surfaces were investigated using wettability measurements, profilometry, photoacoustic and infrared spectroscopy, X-ray photoelectron spectroscopy as well as scanning electron microscopy. The wettability measurements showed that the obtained surfaces are hydrophobic – the water contact angle was in the range of 140-150 degrees. The photoacoustic and infrared spectroscopy as well as X-ray photoelectron spectroscopy disclosed the surface compositions, particularly that of the hydrophobic alkyl groups deposited on them. They were methyl groups introduced during hydrophobization by hexamethyldisilazane. In addition, it was found that the number of groups on the surface depends on the kind of plasma by which the supports were activated. The optical profilometer showed differences in the surface roughness which affects their hydrophobicity. Moreover, the surface free energies were determined using the contact angle hysteresis method. They disclosed differences in each surface, depending on the way of supports activation. The largest hydrophobicity was obtained on the layer deposited on the support activated by the argon plasma. However, support activation by the air plasma resulted in a decrease of hydrophobicity compared to that of the non-activated surface.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 6; 1450-1459
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nano-silica reinforced hybrid light-diffusing films with enhanced mechanical and thermal properties
Autorzy:
Sun, X
Li, N.
Hang, J
Jin, L.
Shi, L
Cheng, Z.
Shang, D
Powiązania:
https://bibliotekanauki.pl/articles/175043.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
optical materials and properties
nanocomposites
light-diffusing films
sol-gel preparation
nanoparticles
Opis:
Ultraviolet-curable hybrid light-diffusing films with good optical, mechanical and thermal properties were prepared by involving vinyl-silane-modified nano-silica into light-diffusing films. The light-diffusing films were two-phase materials consisting of UV-curable matrix and light-diffusing agent. The effect of three different light-diffusing agents, viz. inorganic layered particle (CaCO3), spherical acrylic resin (MR-7HG) and organosilicone resin (KMP-590) and their contents, on the optical properties of light-diffusing films was studied. The results showed the light-diffusing film exhibited good optical properties (the transmittance was 90.7% and the haze was 95.5%) when KMP-590 was a light-diffusing agent and its content was 25%. It was because that KMP-590 showed good transparency, good dispersion in the UV-curable matrix and the greater difference in refractive index with UV-curable matrix and polycarbonate substrate. Furthermore, the effect of nano-silica on the optical, mechanical and thermal properties of the hybrid light-diffusing films was investigated. Compared to that of the light-diffusing films without nano-silica, the haze of the hybrid light-diffusing films containing nano-silica was lightly enhanced to above 98%, while their transmittance basically remained unchanged at a high value (above 89%). Additionally, scratch and abrasion resistance of the hybrid films were obviously improved by nano-silica especially with the particle size of 10–15 nm. Furthermore, the mechanical property and thermal stability of the hybrid films were improved as the content of nano-silica with the particle size of 10–15 nm increased. The enhanced mechanical property and thermal stability of the films could be attributed to the dense structure induced by the increase in network density with the addition of vinyl-silane-modified nano-silica.
Źródło:
Optica Applicata; 2015, 45, 3; 393-404
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesizing and characterization of nano-Graphene Oxide-reinforced Hydroxyapatite Coatings on laser treated Ti6Al4V surfaces
Autorzy:
Bulbul, E.
Aksakal, B.
Powiązania:
https://bibliotekanauki.pl/articles/307020.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
obróbka powierzchni
hydroksyapatyt
zol-żel
surface treatment
hydroxyapatite
nano-graphene oxide
sol-gel
Opis:
Laser-treated Ti6Al4V surfaces were coated by the single-layer hydroxyapatite (HA) and double-layer hydroxyapatite reinforced by the reduced nano-graphene oxide (rGO) using the sol-gel method. The effects of rGO reinforcement at different ratios and sintering temperatures on surface morphology and adhesion strength of the single and double layer coatings (rGO/HA) were analysed. As the initial treatment process, a laser texturing was patterned on the alloy and then, prepared samples were coated. The coated laser-modified HA and HA/rGO-coated Ti6Al4V surfaces were characterized by Raman spectroscopy, X-ray diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and the adhesion strength between the coat and substrates were determined by the standard adhesion tests. The conducted analyses indicated that the substitution of rGO into HA matrix revealed a homogeneous morphology and relatively crack-free coatings on the laser-treated Ti substrate surfaces. Adhesion tests showed that, the HA + rGO (1.0 wt. %) biocomposites exhibited a significant increase in adhesion strength compared to untreated surfaces and to the single HA-coated Ti6Al4V substrates.
Źródło:
Acta of Bioengineering and Biomechanics; 2017, 19, 4; 171-180
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis of vanadium-enriched oxide materials via modified sol-gel route with the use of waste solutions contaminated with vanadium ions
Autorzy:
Weidner, Ewelina
Piasecki, Adam
Siwińska-Ciesielczyk, Katarzyna
Jesionowski, Teofil
Ciesielczyk, Filip
Powiązania:
https://bibliotekanauki.pl/articles/1450632.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
modified sol-gel method
zirconia
vanadium recovery
hybrid oxide materials
harmful metal ions
Opis:
In this study, the synthesis of zirconia as well as zirconia enriched with vanadium by modified sol-gel method was presented. The modification of the method was based on the replacement of the traditional basic promoter of hydrolysis, which is ammonia, with sodium hydroxide solution. The most favorable conditions for the synthesis of zirconium with a new hydrolysis promoter were selected. A comparative analysis of $ZrO_2$ obtained using various hydrolysis promoters was performed. Both materials exhibited almost the same physicochemical properties, which proves that in this case the nature of the hydrolysis promoter used in sol-gel route does not significantly affect the properties of the $ZrO_2$. Then, synthesis of $ZrO_2$/V systems was carried out using model and real solutions containing vanadium ions as hydrolysis promoters. The solutions formed after vanadium catalyst leaching were used as real solutions. The effect of vanadium concentration and the presence of impurities on the final physicochemical properties of the obtained hybrid materials were investigated via scanning electron microscopy (SEM), dynamic light scattering (DLS), energy-dispersive X-ray microanalysis (EDS), Fourier transform infrared spectroscopy (FT-IR), low-temperature nitrogen sorption (BET), thermogravimetric analysis (TGA). The analysis of the obtained results allows to state that the developed technique for the synthesis of $ZrO_2$ and $ZrO_2$/V systems, using a modified sol-gel method, enabled the production of attractive materials.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 6; 60-75
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnesium silicate conjugated with calcium lignosulfonate: In situ synthesis and comprehensive physicochemical evaluations
Autorzy:
Klapiszewski, Ł.
Zietek, J.
Ciesielczyk, F.
Siwinska-Stefanska, K.
Jesionowski, T.
Powiązania:
https://bibliotekanauki.pl/articles/109651.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
biopolymers
hybrid materials
synthetic magnesium silicate
calcium lignosulfonate
in situ sol-gel route
Opis:
The aim of this study was to effectively combine synthetic magnesium silicate with the lignin-derived biopolymer calcium lignosulfonate, using the in situ sol-gel route. Magnesium ethoxide and tetraethoxysilane were used as precursors of MgO and SiO2. The synthesis was carried out in alcoholic solution with the addition of ammonia solution as a promoter of hydrolysis. Calcium lignosulfonate was introduced to the reaction medium prior to the synthesis of magnesium silicate. The resulting hybrid powder material was thoroughly characterized, including morphology and particle sizes (SEM microscopy and the DLS technique), porous structure parameters (the BET method and BJH model), thermal stability (TG analysis) and electrokinetic stability (LDV measurements). FTIR spectral analysis was carried out to confirm the effectiveness of the proposed synthesis methodology. Based on the results, a mechanism is proposed for the MgSiO3/lignosulfonate interactions. The resulting novel type of hybrid material combines the multifunctional nature of the biopolymer (diversity of functional groups) with the well-developed porous structure of synthetic magnesium silicate. Its physicochemical parameters were found to depend significantly on the quantity of lignosulfonate used in the synthesis.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 3; 793-802
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and physicochemical characteristics of titanium dioxide doped with selected metals
Autorzy:
Siwinska-Stefanska, K.
Paukszta, D.
Piasecki, A.
Jesionowski, T.
Powiązania:
https://bibliotekanauki.pl/articles/951839.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
titanium dioxide
sol-gel method
doping
TiO2 surface modification
Fe and Co dopant
Opis:
The paper details with of the preparation and physicochemical characterisation of nano- and microstructured TiO2 doped with Fe and Co produced by the sol-gel method using titanium alkoxide as the precursor of titania as well as iron or cobalt nitrates as dopant sources. Fe and Co doped TiO2 materials were successfully prepared with two different methods. The effect of the dopant type on the synthesis of TiO2 powders was investigated. The physicochemical properties of the studied samples were determined. The characterisation included determination of the dispersion and morphology of the systems (particle size distribution, SEM images), characteristics of porous structure (BET isotherms), crystalline structure (XRD), surface composition (EDS), as well as thermal stability (TG/DTA).
Źródło:
Physicochemical Problems of Mineral Processing; 2014, 50, 1; 265-276
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of fluorine and tungsten co-doping on optical, electrical and structural properties of tin (IV) oxide thin films prepared by sol–gel spin coating method
Autorzy:
Keskenler, E F
Turgut, G
Aydin, S.
Dogan, S
Duzgun, B
Powiązania:
https://bibliotekanauki.pl/articles/175016.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
tin (IV) oxide (SnO2)
fluorine (F) and tungsten (W) co-doping
sol-gel
Opis:
Fluorine and tungsten co-doped tin (IV) oxide (WFTO) thin films have been prepared first time by a sol–gel spin coating method. The effect of F and W co-dopant ratio on optical, electrical and structural properties of SnO2 was investigated. It was found that the optical properties of the films were obviously affected by the co-dopant ratio. When the F:W co-dopant ratio increases from 0.25:0.25 to 0.75:0.50, the transmittance in the short wavelengths slightly increases and transmittance edge shifts towards shorter wavelength. With an increase in the co-dopant ratio, the reduction and red shifts in the optical transmittance edge are very obvious at all wavelengths. Transmittance values at 550 nm for the films have varied between 79.64% and 50.20%. The indirect and direct band gap values for WFTO-1, WFTO-2, WFTO-3 and WFTO-4 samples were calculated to be 3.73, 3.79, 3.48, 3.40 eV and 4.03, 4.04, 3.98, 3.97 eV, respectively. The crystal structure of the films has been investigated by X-ray diffraction patterns. It has been observed that WFTO-1 and WFTO-2 samples have (111) preferential orientation corresponding to SnO2 cubic phase. This orientation almost disappears and changes to tetragonal phase (110) orientation for WFTO-3 and WFTO-4. To the best of our knowledge, this is the first cubic structure observation for SnO2 grown by the sol–gel technique. The electrical properties were also changed with co-doping ratio. The best optical, electrical and structural properties were obtained for mole ratio 0.75:0.50 (F:W).
Źródło:
Optica Applicata; 2013, 43, 4; 663-677
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of porosity on the structure, mechanical properties and cell viability of new bioceramics as potential bone graft substitutes
Autorzy:
Demirel, M.
Aksakal, B.
Powiązania:
https://bibliotekanauki.pl/articles/306668.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
implant dokostny
hydroksyapatyt
zol-żel
porowatość
właściwości mechaniczne
bone graft
hydroxyapatite
sol-gel
porosity
mechanical properties
Opis:
Porous and alternative biografts for possible usages in orthopaedic applications were synthesized by the substitution of gelatin (G), cuttlefish backbone (C), meerschaum sepiolite (S) and hydroxyapatite (H). The effects of different proportions of the Gelatin substitutions on the mechanical properties and structure and cell viability properties of the fabricated biografts were investigated. Throughout the structure and mechanical evaluations, it was found that Gelatin substitution in the fabricated biografts increased the total porosity fraction, particularly for C13G75 and S13G75 biografts. Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) were used for characterization of the synthesized biografts. Furthermore, the cell viability tests for the synthesized biografts were carried out by using the osteoblast cell culture. Throughout the analysis, the synthesized C13G75 and S13G75 biografts generated the highest porosity and better correlation between mechanical properties and structural results contributing with highest cell viability rates.
Źródło:
Acta of Bioengineering and Biomechanics; 2018, 20, 2; 11-22
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of magnesia-doped yttria-stabilized zirconia powders for dental technology applications
Autorzy:
Nakonieczny, D.
Walke, W.
Majewska, J.
Paszenda, Z.
Powiązania:
https://bibliotekanauki.pl/articles/307056.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
stomatologia
protetyka
materiały protetyczne
metoda zol-żel
full ceramic restorations
prosthetic dentistry
sol-gel method
Zirconium Oxide
Opis:
Purpose: This paper is focused on the works concerning on preparing zirconium oxide ceramic blocks recommended for CAD/CAM systems used in prosthetic dentistry for manufacturing fixed prosthetic restorations. Methods: Zirconium-yttrium-magnesium mixed ceramic oxides were prepared by sol-gel method via hydrolysis and condensation of zirconium alkoxide precursor (zirconium (IV) propoxide) with yttrium and magnesium nitrates diluted in 2-propanol. The aim of this work it was to obtain 2% mol yttria stabilized zirconia ceramic powders with magnesium as an additional tetragonal ZrO2 phase stabilizer in amount between 2÷6% mol (with 2% variable). Prepared gels were dried (24 h in 65°C). Obtained powders were mixed with binder (carboxymethyl cellulose) and uniaxial pressed in to a specimens with diameter 38 x 22 x 6 mm. Afterwards green bodies were sintered in range of temperature between 1350-1550°C. Powders and blocks were characterized by Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy, Specific Area Measurement. Results: Highly homogeneous powders with a low open porosity, was obtained. Prepared blocks after sintering showed numerous cracks. Nevertheless blocks was fine grained and show quite reproducible chemical composition. Conclusion: A sol gel wet chemical route of powder synthesis allow to obtain high homogenous ceramic materials with inconsiderable amount of pores with low variation in a diameter. In spite of a reproducible synthesis methods of a ceramic powders, applied to prepare green bodies procedure and sintering manner do not allowed to obtain free from cracks zirconia ceramics blocks.
Źródło:
Acta of Bioengineering and Biomechanics; 2014, 16, 4; 99-106
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phase composition and morphology characteristics of ceria-stabilized zirconia powders obtained via sol-gel method with various pH conditions
Autorzy:
Nakonieczny, D. S.
Paszenda, Z. K.
Basiaga, M.
Radko, T.
Drewniak, S.
Podwórny, J.
Bogacz, W.
Powiązania:
https://bibliotekanauki.pl/articles/306224.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
zol-żel
bioceramika
tlenek cyrkonu
właściwości termiczne
morfologia proszków
sol-gel
bioceramics
zirconia
oxide dopants
thermal properties
powder morphology
Opis:
High purity, fine crystalline, degradation-free at low temperature powders have attracted special interest in CAD/CAM prosthetic dentistry full ceramic restorations. This study reports the preparation and characterisation of zirconia-ceria (0.9ZrO20.1CeO2) powders. Materials were obtained from zirconium-n-alkoxide and cerium nitrate hexahydrate in the pH 2–4 and 8–10. Methods: Zirconia-ceria powders were obtained with the sol-gel method in a humid-free environment. Thermal analysis (TGA/DTA) of the as-prepared materials was made for an assessment of its behaviour at elevated temperatures. Specimens were dried at 80°C and calcinated in two stages: at 300°C with soaking time 2.5 h and 850°C with holding time 2.5 h, in order to evaluate the phase transformations. Thermal analyses of the as-dried powders were made for an assessment of its thermal behaviour during heat treatment up to 1000 °C. By X-ray diffraction (XRD), polymorphs of ZrO2 were identified. Additionally, scanning electron microscopy (SEM) and laser particle size distribution (PSD) were involved for characterisation of morphology of the powders. Results: We found a correlation between the pH of the colloidal system and the morphology of the as-obtained powders. Based on analysis (SEM,PSD), structures were identified known as soft and hard agglomerates. Conclusions: In summary, it can be stated differences were found between powder morphology depending on the used pH, which can be crucial for powder densification during sintering and compacting green bodies which, as a consequence, may be crucial for the lifetime of zirconia prostheses. Correlations between phase composition and pH are difficult to grasp, and require further more sophisticated studies.
Źródło:
Acta of Bioengineering and Biomechanics; 2017, 19, 2; 21-30
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
ZrO2-CeO2 ceramic powders obtained from a sol-gel process using acetylacetone as a chelating agent for potential application in prosthetic dentistry
Autorzy:
Nakonieczny, D.
Paszenda, Z.
Drewniak, S.
Radko, T.
Lis, M.
Powiązania:
https://bibliotekanauki.pl/articles/306436.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
proces zol-żel
metody rentgenowskie
analiza termiczna
ZrO2
protetyka
sol-gel process
X-ray Methods
Thermal Analysis
Prosthetic Dentistry
Opis:
Purpose: The main objective of this study was to obtain single-phase β-ZrO2 powders with so-called soft agglomerates reproducibile morphology with acetyl-acetone as a chelating-agent. To the best of our knowledge there is no avaiable data which determine the effect of acetyl acetone on the phase composition and morphology of ceria-doped ZrO2 powders for biomedical applications. Methods: Twenty variants of powders with different water to zirconia precursor and acetylacetone to zirconia precursor molar ratios were prepared. 0.9ZrO20.1CeO2 powders were obtained by a hydrolysis and condensation and further calcination of zirconium n-propoxide in a simple one-step sol-gel process. Influence of acetyloacetone to zirconia precursor on the phase composition ratio and water to zirconia precursor was investigated. Samples have been characterized by X-ray diffraction (XRD), Raman spectroscopy (RS), thermal analysis (TGA/DTA) and scanning electron microscopy (SEM) measurements. Results: Ceramic powders prepared by sol-gel process, according to the various concentration of chelating agent and water show different morphology and phase composition. Conclusions: Higher molar ratios of AcAc in range with smaller amounts of water cause hard agglomerates, obtained powders are characterized by highly thermally stable behaviour and various phase composition. With higher molar ratios of water to zirconium-n-propoxide so-called soft agglomerates and one phase powders are obtained.
Źródło:
Acta of Bioengineering and Biomechanics; 2016, 18, 3; 53-60
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 17

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies