Authors:K. Lee, Y. Yoon, S. Jeong, Y. Chae, and K. Ko
The effects of acids on the removal of impurity from 2N grade silica have been studied using five leaching acids: 0.2 M-oxalic
acid (pH 1.5 and 2.5), c-aqua regia, 2.5%—HCl/HF, and 1%—HNO3/HF. The presence of 39 impurities in the 2N grade silica and the reference material (RM, 5N grade silica) were investigated
by neutron activation analysis (NAA), X-ray fluorescence (XRF), and inductively coupled plasma mass spectrometry (ICP-MS)
methods. Major impurities of the 2N silica were Al, K, Fe, Na, Ti, Ca, Mg and P. The fractions of the eight major impurities
were 99.2% and 90.9% of total impurity in the 2N and RM silica, respectively. Among the leaching acids, almost all of the
major impurities were removed effectively by the 2.5% HCl/HF leaching acid. All the major impurities, except for phosphorous,
as well as 21 minor and trace impurities could be determined by the NAA.
Authors:Y. Chae, D. Protsenko, E. Lavernia, and B. Wong
Cartilage thermoforming is an emerging surgical technology which uses heat to accelerate stress relaxation in mechanically
deformed tissue specimens. Heat induced shape change in cartilage is associated with complex thermo-mechanical behavior of
which the mechanisms are still a subject of debate. Differential scanning calorimetry (DSC) was used to characterize the threshold
temperatures and enthalpies in cartilage as a function of water content. The DSC identified two enthalpic events in porcine
nasal septal cartilage, which depend on the water content. The change in the water content of cartilage impacts the interactions
between matrix macromolecules and water molecules, which may be associated with a bound-free water transformation (reversible
process) and a denaturation of cartilage (irreversible process).
Authors:S. Chae, Y. Jang, I. Bae, K. Ryu, T. Yudintseva, and S. Yudintsev
This study was aimed at the synthesis, study of phase relations and characterization of the garnet ([Ca1.5GdCe0.5]VIII[ZrFe]VI[FexAl3−x]IVO12, x = 0−2) intended as promising matrix for actinides (Pu) immobilization. The optimum temperatures of the fabrication of the
garnets ceramics are 1400 °C at x = 2 and 1500 °C at x = 0−1. The garnets lattice parameters and the content of Ce, as an imitator of Pu, increased with the content of iron. It
was suggested that the ability of the garnet for incorporation of Pu was closely related to the ionic radii of the elements
occupied the four-and six-coordinated sites of the structure.