• Title/Summary/Keyword: Neutral Radius

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Control of electrical types in the P-doped ZnO thin film by Ar/$O_2$ gas flow ratio

  • Kim, Young-Yi;Han, Won-Suk;Kong, Bo-Hyun;Cho, Hyung-Koun;Kim, Jun-Ho;Lee, Ho-Seoung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.11-11
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    • 2008
  • ZnO has a very large exciton binding energy (60 meV) as well as thermal and chemical stability, which are expected to allow efficient excitonic emission, even at room temperature. ZnO based electronic devices have attracted increasing interest as the backplanes for applications in the next-generation displays, such as active-matrix liquid crystal displays (AMLCDs) and active-matrix organic light emitting diodes (AMOLEDs), and in solid state lighting systems as a substitution for GaN based light emitting diodes (LEDs). Most of these electronic devices employ the electrical behavior of n-type semiconducting active oxides due to the difficulty in obtaining a p-type film with long-term stability and high performance. p-type ZnO films can be produced by substituting group V elements (N, P, and As) for the O sites or group I elements (Li, Na, and K) for Zn sites. However, the achievement of p-type ZnO is a difficult task due to self-compensation induced from intrinsic donor defects, such as O vacancies (Vo) and Zn interstitials ($Zn_i$), or an unintentional extrinsic donor such as H. Phosphorus (P) doped ZnO thin films were grown on c-sapphire substrates by radio frequency magnetron sputtering with various Ar/ $O_2$ gas ratios. Control of the electrical types in the P-doped ZnO films was achieved by varying the gas ratio with out post-annealing. The P-doped ZnO films grown at a Ar/ $O_2$ ratio of 3/1 showed p-type conductivity with a hole concentration and hole mobility of $10^{-17}cm^{-3}$ and $2.5cm^2/V{\cdot}s$, respectively. X-ray diffraction showed that the ZnO (0002) peak shifted to lower angle due to the positioning of $p^{3-}$ ions with a smaller ionic radius in the $O^{2-}$ sites. This indicates that a p-type mechanism was due to the substitutional Po. The low-temperature photoluminescence of the p-type ZnO films showed p-type related neutral acceptor-bound exciton emission. The p-ZnO/n-Si heterojunction LEO showed typical rectification behavior, which confirmed the p-type characteristics of the ZnO films in the as-deposited status, despite the deep-level related electroluminescence emission.

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In vivo 3D Kinematics of Axis of Rotation in Malunited Monteggia Fracture Dislocation

  • Kim, Eugene;Park, Se-Jin;Jeong, Haw-Jae;Ahn, Jin Whan;Shin, Hun-Kyu;Park, Jai Hyung;Lee, Mi Yeon;Tsuyoshi, Murase;Sumika, Ikemototo;Kazuomi, Sugamoto;Choi, Young-Min
    • Clinics in Shoulder and Elbow
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    • v.17 no.1
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    • pp.25-30
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    • 2014
  • Background: Normal elbow joint kinematics has been widely studied in cadaver, whilst in vivo study, especially of the forearm, is rare. Our study analyses, in vivo, the kinematics of normal forearm and of malunited forearm using a three-dimensional computerized simulation system. Methods: We examined 8 patients with malunited Monteggia fracture and 4 controls with normal elbow joint. The ulna and radius were reconstructed from CT data placing the forearm in three different positions; full pronation, neutral, and full supination using computer bone models. We analyzed the axis of rotation 3-dimentionally based on the axes during forearm rotation from full pronation to full supination. Results: Axis of rotation of normal forearm was pitch line, with a mean range of 2 mm, from full pronation to full supination, connecting the radial head center proximally and ulnar fovea distally. In normal forearm, the mean range was 1.32 mm at the proximal radioulnar joint and 1.51 mm at the distal radioulnar joint. However in Monteggia fracture patients, this range changed to 7.65 mm at proximal and 4.99 mm at distal radoulnar joint. Conclusions: During forearm rotation, the axis of rotation was constant in normal elbow joint but unstable in malunited Monteggia fracture patients as seen with radial head instability. Therefore, consideration should be given not only to correcting deformity but also to restoring AOR by 3D kinematics analysis before surgical treatment of such fractures.

Lipids and Fatty Acids Composition of Korean Native Goat's Bone Marrow (한국 재래산양 골수의 지질 및 지방산 조성)

  • Lee, Y.Y.;Ha, J.K.;Ahn, B.H.;Kang, D.H.;Ki, W.K.;Kim, J.K.
    • Applied Biological Chemistry
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    • v.31 no.2
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    • pp.177-181
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    • 1988
  • Korean native goat's bone marrow was low in triglycerides high in phospholipids and glycolipids. In the fatty acid composition, goat's bone marrow was high in $C_{18:1}$ and low in $C_{18:0}$. Goat's bone marrow also contained more unsaturated fatty acid than saturated fatty acid. Triglyceride and sterylester were more than others in the neutral lipids. Esterified glycoside and monogalactosyl diglyceride were higher than others in the glycolipids. Diphosphatidyl glycerol and phosphatidyl ethanolamine were higher than others in the phospholipids. In the fatty acid composition of triglycerides, Humerus and Radius, Femur and Os coxae and Lumbar vertebra were all higher in $C_{16:0}$, $C_{18:0}$ and $C_{18:1}$ than others in the 1-position of triglycerides and higher in $C_{18:0}$, $C_{18:2}$ and $C_{18:3}$ than others in the 2-position of triglycerides.

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