• Title/Summary/Keyword: Yttrium

Search Result 402, Processing Time 0.024 seconds

Magnetic Properties of Heteroepitaxial $Y_{3}Fe_{5)O_{12}$ Films Grown by a Pulsed Laser Ablation Technique (펄스 레이저 증착기술에 의한 $Y_{3}Fe_{5)O_{12}$ 에피택셜 박막제조)

  • Yang, C.J.;Kim, S.W.
    • Journal of the Korean Magnetics Society
    • /
    • v.5 no.2
    • /
    • pp.128-133
    • /
    • 1995
  • Yttrium Iron Garnet($Y_{3}Fe_{5)O_{12}$) films have been succsssfully grown on(111)GGG wafer by KrF excimer laser ablation of stoichiometric garnet target at the oxygen partial pressure, $P(O_{2}$, ranging 20 to 500 mTorr. During the deposition of the films the substrate temperature was maintained at $700^{\circ}C$ and the laser beam energy density at $7.75\;J/cm_{2}$. Microstructure, composition and magnetic properties of the films obtained were investigated as a function of oxygen pressure and thickness of the films. Epitaxial films with a dense and a smooth surface were reproducible at a low oxygen pressure. The films of $2.75\;{\mu}$ min thickness deposited at 20 mTorr of $P(O_{2})$ showed $4{\pi}M_{s}$ of 1500 Gauss and $H_{c}$ of 3 Oe after annealing at $800\;^{\circ}C$ for 20 minutes. As-deposited films of $0.8\;\mu\textrm{m}$ in thickness exhibited the $4{\pi}M_{s}$ of 1730 Gauss and $H_{c}$ of 7 Oe. The magnetic properties of the films obtained were almost identical to those of a single crystal YIG.

  • PDF

Assessment of Acquisition Protocols for Post-Radioembolization Yttrium-90 PET/CT: Initial Study (90Y SIR-Spheres를 사용한 암의 간 전이치료에서 PET 영상획득에 관한 초기연구)

  • Bahn, Young Kag;Oh, Shin Hyun;Kim, Jung Yul;Lee, Seung Jae;Park, Joon Young;Shin, Heui Soon;Lim, Han Sang;Kim, Jae Sam
    • The Korean Journal of Nuclear Medicine Technology
    • /
    • v.18 no.1
    • /
    • pp.89-93
    • /
    • 2014
  • Purpose: We investigated the quantitative evaluation of PET/CT images for evaluation after treatment in the treatment of liver metastasis of cancer with $^{90}YSIR$-Sphere. Materials and Methods: Confirmed the correlation between the measured counts was expressed by setting a region of interest from the image and a measure of the dose calibrator to see a correlation diagram of an image in a PET of $^{90}Y$. A portion uptake coefficients between PET images were acquired for 20 minutes LIST mode in 15 patients treated for liver metastasis of cancer using $^{90}Y$ SIR-Spheres high, intermediate portion, a lower portion, three measuring the coefficient of the region of interest is divided into parts, we studied the conditions for proper image acquisition. Results: Coefficient of sites that set the region of interest of the PET image and the measured counts of $^{90}Yappears$ that there is a correlation diagram statistically, ($R^2=0.956$), correlation diagram from the PET image of $^{90}Yis$, PET coefficient the coefficients of all regions of interest were increased in proportion to the image acquisition time, partial ROI coefficients of the PET image is higher about 10 minutes on average, about 14 minutes on average, the central portion is lower part 19 minute average in, confirmed the equilibrium of the standard deviation. Conclusion: Using the isotope $^{90}Y$, it is suitable to obtain a PET image, to obtain the time of proper image, the evaluation of PET/CT images, using the $^{90}Y$ SIR-Spheres and that in the treatment of liver metastases of cancer, it is useful for assessing treatment.

  • PDF