Development of Radioactive Sources on the Basis of Bioinert Ceramic Materials for Medical Applications and their Pre-Clinical Testing

2014 ◽  
Vol 1040 ◽  
pp. 286-291
Author(s):  
Tamara Khabas ◽  
Ekaterina Kulinich ◽  
Victor Merkulov ◽  
Сhristoph Roesli ◽  
Mihail Martusevich
Keyword(s):  
Thermal Expansion ◽  
Ceramic Materials ◽  
Medical Applications ◽  
Clinical Testing ◽  
Titanium Metal ◽  
Strontium Oxide ◽  
Disease Treatment ◽  
Radioactive Sources ◽  
Composite Properties ◽  
Bioinert Ceramic

In this article, both the composition and composite properties of radioactive sources for medical applications are worked out and studied. The bases of these sources are bioinert ceramic solids and radionuclides. The active source is constituted from dispersed radioactive yttriа oxide or strontium oxide monolithically encapsulated with bioinert glass flux. The thermal expansion properties of the analyzed composites are highly similar to the ones of both titanium metal and titanum alloys. Therefore, the developed radioactive sources can be mounted on titanium holder. Importantly, all utilized elements and alloys are already applied in medicine. In this article we demonstrate the use of a radioactive β-source placed on a titanium holder. The device is finally applied in a oncological model disease treatment.

scholarly journals Phase Transition and Coefficients of Thermal Expansion in Al2−xInxW3O12 (0.2 ≤ x ≤ 1)

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4021
Author(s):  
Andrés Esteban Cerón Cerón Cortés ◽  
Anja Dosen ◽  
Victoria L. Blair ◽  
Michel B. Johnson ◽  
Mary Anne White ◽  
...  
Keyword(s):  
Phase Transition ◽  
Thermal Expansion ◽  
Thermal Shock ◽  
Monoclinic Phase ◽  
Ceramic Materials ◽  
Precipitation Method ◽  
Scanning Calorimetry ◽  
Orthorhombic Crystal ◽  
Co Precipitation

Materials from theA2M3O12 family are known for their extensive chemical versatility while preserving the polyhedral-corner-shared orthorhombic crystal system, as well as for their consequent unusual thermal expansion, varying from negative and near-zero to slightly positive. The rarest are near-zero thermal expansion materials, which are of paramount importance in thermal shock resistance applications. Ceramic materials with chemistry Al2−xInxW3O12 (x = 0.2–1.0) were synthesized using a modified reverse-strike co-precipitation method and prepared into solid specimens using traditional ceramic sintering. The resulting materials were characterized by X-ray powder diffraction (ambient and in situ high temperatures), differential scanning calorimetry and dilatometry to delineate thermal expansion, phase transitions and crystal structures. It was found that the x = 0.2 composition had the lowest thermal expansion, 1.88 × 10−6 K−1, which was still higher than the end member Al2W3O12 for the chemical series. Furthermore, the AlInW3O12 was monoclinic phase at room temperature and transformed to the orthorhombic form at ca. 200 °C, in contrast with previous reports. Interestingly, the x = 0.2, x = 0.4 and x = 0.7 materials did not exhibit the expected orthorhombic-to-monoclinic phase transition as observed for the other compositions, and hence did not follow the expected Vegard-like relationship associated with the electronegativity rule. Overall, compositions within the Al2−xInxW3O12 family should not be considered candidates for high thermal shock applications that would require near-zero thermal expansion properties.

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.

Survey on lost and poorly controlled radioactive sources in non-medical applications in Iran

2005 ◽  
Vol 118 (4) ◽  
pp. 375-377 ◽  
Author(s):  
F. A. Mianji ◽  
M. R. Kardan ◽  
N. Rastkhah
Keyword(s):  
Medical Applications ◽  
Radioactive Sources

A fogászati kerámiaanyagok fejlődésének történeti áttekintése

2021 ◽  
Vol 11 (22) ◽  
pp. 284-293
Author(s):  
József Saláta
Keyword(s):  
Thermal Expansion ◽  
18Th Century ◽  
Ceramic Materials ◽  
Dental Ceramics ◽  
New Techniques ◽  
Casting Alloys ◽  
Burnt Clay ◽  
Cad Cam ◽  
Increasing Demand ◽  
Dental Casting Alloys

Initially, ceramics - mostly burnt clay - were used to manufacture container pottery. The first porcelain objects reached Europe out of China in the Medieval Ages. The technique of their manufacturing was a mystery for many hundred years, yet Germans succeeded first to produce fine European porcelain at the beginning of the 18th century. Its elegance and hardness woke the dentists’ interest too thus Frenchmen created the first porcelain dentures in the second half of the 18th century. Since then, there has been an increasing demand for esthetic fixed implant dentures instead of removable ones. The development of ceramic materials resulted in better mechanical and optical properties, thus the first fixed porcelain inlays and jacket crowns were introduced already in 1889. The addition of leucite filler crystals to porcelain in the 20th century increased the thermal expansion of the ceramic. It could be fired on common dental casting alloys, so the first porcelain-fused-to-metal (PFM) crown was created in 1962. Several new techniques were developed from the middle of the 1980s to the end of the 1990s to deal with initial shrinkage and achieve better properties. Beyond casting, pressing, and CAD/CAM technology, additive manufacturing opened new perspectives in dentistry several years ago in processing dental ceramics.

A new generation of bio‐derived ceramic materials for medical applications

2008 ◽  
Vol 88A (3) ◽  
pp. 807-813 ◽  
Author(s):  
P. González ◽  
J. P. Borrajo ◽  
J. Serra ◽  
S. Chiussi ◽  
B. León ◽  
...  
Keyword(s):  
Ceramic Materials ◽  
Medical Applications ◽  
New Generation

Effect of Si3N4-Y2O3 Compound Additive on Crystallization and Sintering of Fused Quartz Ceramic Materials

2011 ◽  
Vol 335-336 ◽  
pp. 713-716
Author(s):  
Shu Long Liu ◽  
Zhi Fa Wang ◽  
Jing Long Bu ◽  
Shu Bin Shen ◽  
Li Xue Yu
Keyword(s):  
Thermal Expansion ◽  
Bending Strength ◽  
Ceramic Materials ◽  
Quartz Ceramic ◽  
Apparent Porosity ◽  
Raw Material ◽  
Expansion Rate ◽  
Obvious Effect ◽  
Fused Quartz

Fused quartz granules (d50=19 μm) were used as raw material, and Si3N4-Y2O3 (1:1, in mass) was used as additive with dosages of 1%, 2% and 3% (in mass). Fused quartz ceramic materials were fabricated in reduction atmosphere at 1300 °C, 1350 °C and 1400 °C for 1 h. The effect of Si3N4-Y2O3 on crystallization and sintering of the fused quartz ceramic materials were researched by measurements of apparent porosity, bending strength and thermal expansion rate (RT~1200 °C), and by the analyses of XRD and SEM. The results showed that the samples sintered at each temperature with 3% Si3N4-Y2O3 had the lowest apparent porosity, the highest bending strength and more compact microstructure. This indicated that 3% Si3N4-Y2O3 was conducive to sintering of fused quartz ceramic materials. The results of XRD and thermal expansion rate showed that addition of 3% Si3N4-Y2O3 compound had obvious effect on inhibiting crystallization of the samples sintered at various temperatures. It can be deduced that the Si3N4-Y2O3 compound plays the best role in inhibiting crystallization and facilitating sintering of fused quartz ceramic materials.

Influence of Nano-Y2O3 on Crystallization Behavior and Sintering Performance of Fused Quartz Ceramic Materials

2011 ◽  
Vol 284-286 ◽  
pp. 1366-1369
Author(s):  
Yue Jun Chen ◽  
Zhi Fa Wang ◽  
Li Xue Yu ◽  
Jing Long Bu ◽  
Rong Lin Wang ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Bending Strength ◽  
Ceramic Materials ◽  
Quartz Ceramic ◽  
Apparent Porosity ◽  
Raw Material ◽  
Expansion Rate ◽  
Peak Intensity ◽  
Fused Quartz ◽  
Crystallization Inhibitor

Fused quartz granule (d50=0.019 mm) was used as raw material, nano-Y2O3 (size<0.08 μm) was used as additive with dosages of 1% (in mass, similarly hereinafter), 2% and 3%. Fused quartz ceramic materials were fabricated in reduction atmosphere at 1300 °C, 1350 °C and 1400 °C for 1 h. Properties of samples were researched by measurements of apparent porosity, bending strength and thermal expansion rate, and analyzed by XRD and SEM. The results showed that additive nano-Y2O3 had good inhibiting effect on crystallization of fused quartz sintered at various temperatures, sample added 2% nano-Y2O3 had least thermal expansion rate, diffraction peak intensity and apparent porosity, and it had higher bending strength and more compact microstructure, especially sample sintered at 1350 °C. It can be deduced that 2% nano-Y2O3 plays the excellent role as the crystallization inhibitor and sintering assistant to fused quartz materials sintered at various temperatures.

Effect of Si3N4-Nd2O3 Compound Additive on Crystallization and Sintering of Fused Quartz Ceramic Materials

2011 ◽  
Vol 335-336 ◽  
pp. 728-731
Author(s):  
Shu Bin Shen ◽  
Jing Long Bu ◽  
Li Xue Yu ◽  
Shu Long Liu ◽  
Zhi Fa Wang
Keyword(s):  
Thermal Expansion ◽  
Bending Strength ◽  
Ceramic Materials ◽  
Expansion Ratio ◽  
Quartz Ceramic ◽  
Apparent Porosity ◽  
Raw Material ◽  
Ratio Analysis ◽  
Fused Quartz

Fused quartz granules (d50=19 μm) were used as raw material, and Si3N4-Nd2O3 (1:1, in mass) was used as additive with dosages of 1% (in mass, similarly hereinafter), 2% and 3%. Fused quartz ceramic materials were fabricated in reduction atmosphere at 1300 °C, 1350 °C and 1400 °C for 1 h. The apparent porosity, bending strength and thermal expansion ratios of the samples were studied and the samples were further analysed by means of XRD and SEM. The results showed that the sample sintered at each temperature with 3% Si3N4-Nd2O3 had the lowest apparent porosity, the highest bending strength and more compact microstructure. This indicated that 3% Si3N4-Nd2O3 was useful to the sintering of fused quartz ceramic materials. The results of XRD and thermal expansion ratio analysis showed that 3% Si3N4-Nd2O3 compound additive had better effect on inhibiting crystallization of the samples sintered at 1300 °C, 1350 °C and 1400 °C.

Strain contrast in SiC whisker reinforced Al2O3

1986 ◽  
Vol 44 ◽  
pp. 498-499
Author(s):  
P. Angelini ◽  
W. Mader
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Thermal Expansion ◽  
Quantitative Analysis ◽  
Residual Stresses ◽  
Strain Field ◽  
Ceramic Materials ◽  
Spherical Particles ◽  
The Matrix ◽  
Sic Whiskers

Whisker reinforced ceramic materials offer the potential for increased fracture toughness and fracture strength. Residual stresses resulting from differences in thermal expansion properties of the matrix and the whisker can develop during cooling and affect mechanical properties. TEH strain contrast of large inclusions has previously been observed for nearly spherical particles of ZrO2 in Al2O3 matrix grains. The formation of strain contrast oscillations was explained and a quantitative analysis of strains around ZrO2 inclusions in Al2O3 was performed. The present research is concerned with characterizing by TEM the strain field present in Al2O3 reinforced with SiC whiskers.

Sign in / Sign up

Export Citation Format

Share Document