Accession Number : ADP014407


Title :   Microstructure and Thermal Expansion Properties of Ostrich Eggshell


Descriptive Note : Conference paper


Corporate Author : YOKOHAMA NATIONAL UNIV (JAPAN) FACULTYOF ENGINEERING


Personal Author(s) : Heredia, A ; Lozano, L ; Martinez-Matias, C A ; Pena-Rico, M A ; Rodriguez-Hernandez, A


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/p014407.pdf


Report Date : Apr 2002


Pagination or Media Count : 7


Abstract : Textures of calcite crystals from ostrich (Struthio camelus) eggshells were examined with X ray diffractometry (XRD), transmission and scanning electron microscopy (TEM, SEM), and the thermal stability by thermal expansion analysis (TEA). Results showed that textures vary through the thickness of the eggshell and that expansion properties and thermal behaviour are unusual. Crystals from ostrich eggshell are arranged in two main configurations or layers; the outer layer with the c-axis of crystals oriented perpendicular to the eggshell surface and the inner layer with the c-axes of the crystals arranged almost parallel to eggshell surface; thermal expansion analysis show high stability through a wide range of temperatures until a steep growth near 450-460 degrees C. These results show that the manipulation of crystal texture and properties is under biological control and a better understanding of this biological phenomenon will provide more and better data for improving new synthetic composite materials.


Descriptors :   *MICROSTRUCTURE , *X RAY DIFFRACTION , *THERMAL EXPANSION , *EGGS , *DIFFRACTOMETERS , TEMPERATURE , STABILITY , SCANNING ELECTRON MICROSCOPES , COMPOSITE MATERIALS , THERMAL STABILITY , CRYSTALS , JAPAN , ELECTRON MICROSCOPY , THERMAL ANALYSIS , CONFIGURATIONS , CALCITE , RANGE(EXTREMES) , TEXTURE , SYNTHETIC MATERIALS , MEXICO


Subject Categories : Biology
      Textiles
      Thermodynamics


Distribution Statement : APPROVED FOR PUBLIC RELEASE