Study on Properties of Leucite for Dental Porcelain Compositions

2011 ◽  
Vol 66-68 ◽  
pp. 1522-1527
Author(s):  
Li Na Sui ◽  
Li Yan Yu ◽  
Li Feng Dong
Keyword(s):  
Heat Treatment ◽  
Thermal Expansion ◽  
Powder Diffraction ◽  
Coefficient Of Thermal Expansion ◽  
Raw Materials ◽  
Clinical Applications ◽  
High Concentration ◽  
Melt Quenching ◽  
Dental Porcelain ◽  
X Ray

Leucite crystal was prepared using SiO2-Al2O3-K2CO3-Na2CO3as raw materials and adopting melt quenching and appropriate heat treatment temperatures. The crystal was characterized and analyzed by X-ray powder diffraction, the coefficient of thermal expansion, and biocompatibility. The results showed that appropriate Na2O could advance the growth of leucite, but high concentration facilitates the formation of KAlSiO4crystal. The coefficient of thermal expansion was 24.52×10-6/°C at 600 °C, and thereby the coefficient could be adjusted by adding appropriate amount of leucite. The biocompatibility of leucite was almost the same as the Songfeng powder for clinical applications.

BaO-Al2O3-SiO2-B2O3 Glass-Ceramic SOFCs Sealant: Effect of ZnO Additive

2017 ◽  
Vol 751 ◽  
pp. 455-460 ◽  
Author(s):  
Nattapol Laorodphan ◽  
Jiratchaya Ayawanna
Keyword(s):  
Heat Treatment ◽  
Thermal Expansion ◽  
Solid Oxide Fuel Cells ◽  
Glass Ceramic ◽  
Coefficient Of Thermal Expansion ◽  
Glass Ceramics ◽  
Treatment Temperature ◽  
X Ray ◽  
Barium Aluminosilicate ◽  
Xrd Patterns

The crystallization of planar solid oxide fuel cells (SOFCs) sealant glasses in the systems BaO-Al2O3-SiO2-B2O3 (BaBS) and BaO-Al2O3-SiO2-B2O3-ZnO (BaBS-Zn) was investigated via both X-ray diffractometer and scanning electron microscopy with energy dispersive spectroscopy. The effect of nucleation heat-treatment of the BaBS glass at different temperature for 5 hours, i.e. 550 and 590 °C, on the crystallization behavior was also studied. Thermal expansion profiles of the glasses indicate that both glasses have a low sealing temperature. XRD patterns of all BaBS glass-ceramics, devitrified at 800 °C for 30 hours, show that Ba2Si3O8, BaAl2Si2O8, Ba3B2O6 and some unknown crystalline phases were found. It was also found that crystalline size of unknown barium aluminosilicate with low silicon content depends on the nucleation heat-treatment temperature. For the ZnO-containing glass, ZnO reduces the coefficient of thermal expansion value of glass and causes the devitrification of large needle-like barium zinc silicate phases. The crack at the YSZ/BaBS-Zn glass-ceramic interface was also observed. Two barium silicate phases, which are BaZnSiO4 and BaZn2Si2O7 were devitrified in ZnO-containing glass-ceramic.

In situ investigation of the interfacial reaction in Sn/Cu system by synchrotron radiation

2010 ◽  
Vol 25 (5) ◽  
pp. 972-975 ◽  
Author(s):  
Kai-Jheng Wang ◽  
Yung-Chi Lin ◽  
Jenq-Gong Duh ◽  
Ching-Yuan Cheng ◽  
Jey-Jau Lee
Keyword(s):  
Thin Film ◽  
Heat Treatment ◽  
Thermal Expansion ◽  
Synchrotron Radiation ◽  
Interfacial Reaction ◽  
Coefficient Of Thermal Expansion ◽  
X Ray ◽  
In Situ Investigation ◽  
Cu Thin Film

In situ investigation of the interfacial reaction in the Sn/Cu thin film during aging, and reflow was carried out by synchrotron radiation with high intensity and high resolution of x-ray. With this technique, the phase transformation and evolution of the Sn/Cu thin film during heat treatment can be directly and continuously investigated. Moreover, the information for coefficient of thermal expansion in intermetallic compounds was also evaluated by this approach.

Powder Diffraction and Dilatometric Study of SrFe12O19

2019 ◽  
Vol 946 ◽  
pp. 336-340
Author(s):  
Svetlana A. Gudkova ◽  
Danil A. Uchaev ◽  
D.A. Vinnik
Keyword(s):  
Thermal Expansion ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Coefficient Of Thermal Expansion ◽  
Strontium Hexaferrite ◽  
X Ray Diffraction ◽  
Spontaneous Crystallization ◽  
X Ray ◽  
Cell Parameters ◽  
Good Agreement

Strontium hexaferrite is a well-known material, due to its application in microelectronics. This paper is devoted to strontium hexaferrite single crystals, obtained by the spontaneous crystallization technique with sodium based flux. SrFe12O19 crystals were grounded, pressed to the tablets, and crystals cell parameters were measured by thermal X-ray diffraction technique. Coefficient of thermal expansion calculated from the X-ray thermal diffraction data is in a good agreement with dilatometric measurements.

Crystal Transition and Drug-excipient Compatibility of Clarithromycin in Sustained Release Tablets

2020 ◽  
Vol 16 (7) ◽  
pp. 950-959
Author(s):  
Yu Li ◽  
Xiangwen Kong ◽  
Fan Hu
Keyword(s):  
Sustained Release ◽  
Powder Diffraction ◽  
Magnesium Stearate ◽  
Influential Factor ◽  
High Concentration ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Sustained Release Tablets ◽  
Crystal Transition ◽  
Excipient Compatibility

Background: Clarithromycin is widely used for infections of helicobacter pylori. Clarithromycin belongs to polymorphic drug. Crystalline state changes of clarithromycin in sustained release tablets were found. Objective: The aim of this study was to find the influential factor of the crystal transition of clarithromycin in preparation process of sustained-release tablets and to investigate the possible interactions between the clarithromycin and pharmaceutical excipients. Methods and Results: The crystal transition of active pharmaceuticals ingredients from form II to form I in portion in clarithromycin sustained release tablets were confirmed by x-ray powder diffraction. The techniques including differential scanning calorimetry and infrared spectroscopy, x-ray powder diffraction were used for assessing the compatibility between clarithromycin and several excipients as magnesium stearate, lactose, sodium carboxymethyl cellulose, polyvinyl-pyrrolidone K-30 and microcrystalline cellulose. All of these methods showed compatibilities between clarithromycin and the selected excipients. Alcohol prescription simulation was also done, which showed incompatibility between clarithromycin and concentration alcohol. Conclusion: It was confirmed that the reason for the incompatibility of clarithromycin with high concentration of alcohol was crystal transition.

scholarly journals Sintering Behavior, Thermal Expansion, and Environmental Impacts Accompanying Materials of the Al2O3/ZrO2 System Fabricated via Slip Casting

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3365
Author(s):  
Justyna Zygmuntowicz ◽  
Magdalena Gizowska ◽  
Justyna Tomaszewska ◽  
Paulina Piotrkiewicz ◽  
Radosław Żurowski ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Life Cycle ◽  
Coefficient Of Thermal Expansion ◽  
Raw Materials ◽  
Slip Casting ◽  
Ceramic Materials ◽  
Sintering Behavior ◽  
Environmental Loads ◽  
Practical Applications ◽  
Technical Ceramics

This work focuses on research on obtaining and characterizing Al2O3/ZrO2 materials formed via slip casting method. The main emphasis in the research was placed on environmental aspects and those related to the practical use of ceramic materials. The goal was to analyze the environmental loads associated with the manufacturing of Al2O3/ZrO2 composites, as well as to determine the coefficient of thermal expansion of the obtained materials, classified as technical ceramics. This parameter is crucial in terms of their practical applications in high-temperature working conditions, e.g., as parts of industrial machines. The study reports on the four series of Al2O3/ZrO2 materials differing in the volume content of ZrO2. The sintering process was preceded by thermogravimetric measurements. The fabricated and sintered materials were characterized by dilatometric study, scanning electron microscopy, X-ray diffraction, and stereological analysis. Further, life cycle assessment was supplied. Based on dilatometric tests, it was observed that Al2O3/ZrO2 composites show a higher coefficient of thermal expansion than that resulting from the content of individual phases. The results of the life cycle analysis showed that the environmental loads (carbon footprint) resulting from the acquisition and processing of raw materials necessary for the production of sinters from Al2O3 and ZrO2 are comparable to those associated with the production of plastic products such as polypropylene or polyvinyl chloride.

Studies of the Coefficient of Thermal Expansion of Low-k ILD Materials by X-Ray Reflectivity

2006 ◽  
Vol 914 ◽  
Author(s):  
George Andrew Antonelli ◽  
Tran M. Phung ◽  
Clay D. Mortensen ◽  
David Johnson ◽  
Michael D. Goodner ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermal Expansion ◽  
Coefficient Of Thermal Expansion ◽  
Chemical Vapor ◽  
Dielectric Materials ◽  
Free Standing ◽  
Dielectric Thin Films ◽  
X Ray ◽  
Chemical Vapor Deposited ◽  
Low K

AbstractThe electrical and mechanical properties of low-k dielectric materials have received a great deal of attention in recent years; however, measurements of thermal properties such as the coefficient of thermal expansion remain minimal. This absence of data is due in part to the limited number of experimental techniques capable of measuring this parameter. Even when data does exist, it has generally not been collected on samples of a thickness relevant to current and future integrated processes. We present a procedure for using x-ray reflectivity to measure the coefficient of thermal expansion of sub-micron dielectric thin films. In particular, we elucidate the thin film mechanics required to extract this parameter for a supported film as opposed to a free-standing film. Results of measurements for a series of plasma-enhanced chemical vapor deposited and spin-on low-k dielectric thin films will be provided and compared.

Magnetic and Structural Properties of Ferrimagnetic Bioceramics

2005 ◽  
Vol 473-474 ◽  
pp. 117-122 ◽  
Author(s):  
A.C. Kis ◽  
Th. Leventouri ◽  
J.R. Thompson
Keyword(s):  
Crystal Structure ◽  
Heat Treatment ◽  
Magnetic Properties ◽  
Calcium Phosphate ◽  
Powder Diffraction ◽  
Magnetic Measurements ◽  
Treatment Temperature ◽  
Monoclinic Crystal ◽  
X Ray ◽  
Phase Development

Structure and magnetic properties of ferrimagnetic bioceramics in the system {0.45(CaO, P2O5) ySiO2 xFe2O3 0.03Na2O}, x=0.05, 0.10, 0.15, 0.20, were studied by x-ray powder diffraction and magnetic measurements. Magnetite and calcium phosphate, crystallizing in the hexagonal and monoclinic crystal systems, are the major phases in the compounds. Phase development, crystal structure, and magnetic properties of the composites are determined by the specific starting composition of oxides and the heat-treatment temperature.

The crystal structure and thermal expansion of the CCl4 adduct of Dianin's compound

1990 ◽  
Vol 68 (8) ◽  
pp. 1352-1356 ◽  
Author(s):  
Walter Abriel ◽  
André Du Bois ◽  
Marek Zakrzewski ◽  
Mary Anne White
Keyword(s):  
Crystal Structure ◽  
Thermal Expansion ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
X Ray Diffraction ◽  
Guest Molecules ◽  
X Ray ◽  
Thermal Expansion Coefficients ◽  
Expansion Coefficients ◽  
Dianin's Compound

The crystal structure of the title compound has been determined by single crystal X-ray diffraction data collected at 293 K, and refined to a final Rw of 0.057. The crystals are rhombohedral, space group [Formula: see text], with a = 27.134(8) Å, c = 10.933(2) Å, and Z = 18. The mole ratio of Dianin's compound (4-p-hydroxyphenyl-2,2,4-trimethylchroman) to CCl4 is 6:1. The guest molecules are disordered. X-ray powder diffraction was carried out in the temperature range from 10 to 300 K. From this, the thermal expansion coefficients for the a- and c-axes and the volume have been determined. Keywords: thermal expansion, crystal structure, clathrate.

Sign in / Sign up

Export Citation Format

Share Document