• Title/Summary/Keyword: high-purity

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Inhomogeneous Rolling Texture of Multilayered Aluminum Sheet (다층압연된 알루미늄의 불균질압연집합조직)

  • Choi, Chang-Hee;Hong, Seung-Hyun;Kwon, Jae-Wook;Oh, Kyu-Hwan;Lee, Dong-Nyung
    • Transactions of Materials Processing
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    • v.4 no.4
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    • pp.353-364
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    • 1995
  • An inhomogeneous rolling texture of high purity aluminum has been observed by a multilayered rolling. The shear texture of (100)[110] component developed in the surface layer, and the copper type rolling texture developed in the middle and center layers. The through-thickness texture variation has been calculated by the full-constraint Taylor model combined with FEM. The calculated results are in good agreement with the measured data.

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ISOTOPIC-SPECTRAL DETERMINATION OF CARBON IN HIGH PURITY INORGANIC MATERIALS

  • Lee, V.N.;Nemets, V.M.
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.477-480
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    • 1995
  • Isotopic-spectral method [I] was applicated for determination of carbon in silicate materials (pure silica, guartz glasses, geological probs etc.). Isotopic heterogeneous balancing of carbon in gaseous phase and solid samples was carried out at the temperature of $1500-1900^{\circ}K$. Spectroscopic measuring of isotope concentration in a balanced gas was made using the electron-vibrational band heads of CO molecules excited in HF discharge. Limits of detection of carbon concentrations appear to be $n^*10^{-6}$.

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A Study of PTCR Effects in Semiconducting BaTiO3 Prepared by Direct Wet Process (습식 직접합성법에 의한 반도성 BaTiO3의 PTCR 효과에 관한 연구)

  • 이경희;이병하;정연식
    • Journal of the Korean Ceramic Society
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    • v.24 no.2
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    • pp.111-116
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    • 1987
  • By the method of direct wet process which has been developed in our laboratory, the high purity BaTiO3 powders could be synthesized from the room temperature to 90$^{\circ}C$ according to particle sizes. For to detect the PTCR effects, Sb2O3 wasdoped in the BaTiO3 powders which had been prepared on above method. As the results, the PTCR effects were in creased with the decreasing grain size of BaTiO3 powders.

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Computer Simulation of Solidification in L-Sections (L형(型) 주물응고(鑄物凝固)에 대한 Computer Simulation)

  • Han, Yoon-Hee;Kim, Myung-Han;Kim, Dong-Ok
    • Journal of Korea Foundry Society
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    • v.5 no.2
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    • pp.125-136
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    • 1985
  • The most desirable method for the solution of solidification problems in castings must be the one which combines accuracy, simplicity, and low computer usage cost. The purpose of the present study is to develop a method which includes all these advantages. The purpose of the present research was approached by the introduction of two methods: (1) A pour-out test, employed with very high purity aluminum, for the purpose of obtaining accurate solidification data in L-sections; and (2) an numerical technique, using the cubic spline function for defining solidification curves.

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A Study on the Purification Process of Alumina by Powder Technics (알루미나 정제공정의 분체공학적 연구)

  • 백행남;서태수;곽중협
    • Journal of the Korean Ceramic Society
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    • v.25 no.6
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    • pp.655-664
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    • 1988
  • As a part of study to establish the industrial process for manufacturing high purity alumina powder which is largely used as fine ceramics, an adsorption method using a silica-containing material which can absorb to eliminate a major impurity, Na in aluminum hydroxide as a raw material has been studied. It is confirmed that the primary property of powder such as the particle size of raw material and that of silica-containing material plays a great important role in the purification process.

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Synthesis of Nanosized Powders by Wire Explosion (전기폭발(wire explosion)에 의한 나노분말 제조)

  • Cho, Chu-Hyun;Rim, Geun-Hie;Lee, Hong-Sik;Jiang, WeiHua
    • Proceedings of the KIEE Conference
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    • 2005.07c
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    • pp.2057-2059
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    • 2005
  • Silver nanosized powder have been synthesized using wire explosion technology. The discharge system of 10kw (10uF, 20kV, 0.5 shots/s) was set up for mass production of 300g/h. The high purity silver powder was collected and separated by cyclone and fabric filters.

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SIPPING TEST: CHECKING FOR FAILURE OF FUEL ELEMENTS AT THE OPAL REACTOR

  • Smith, Michael Leslie;Bignell, Lindsey Jorden;Alexiev, Dimitri;Mo, Li
    • Nuclear Engineering and Technology
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    • v.42 no.1
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    • pp.125-130
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    • 2010
  • Sipping measurements were implemented at the Open Pool Australian Light water reactor (OPAL) to test for failure in reactor fuel elements. Fission product released by the fuel element into the pool water was measured using both High Purity Germanium (HPGe) detection via samples and a NaI(Tl) detection in-situ with the sipping device. Results from two fuel elements are presented.

Effect of surfactant on the micelle process for the pre-purification of paclitaxel (Paclitaxel 전처리를 위한 마이셀 공정에서의 계면활성제 영향)

  • Jeon, Keum-Young;Kim, Jin-Hyun
    • KSBB Journal
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    • v.23 no.6
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    • pp.557-560
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    • 2008
  • The micelle process was developed for pre-purifying paclitaxel from plant cell cultures of Taxus chinensis, giving a high purity and yield. The approach in this work was to transfer paclitaxel in the crude extract to an aqueous surfactant solution as a micelle, allowing organic solvents to be used for removal of lipids and non-polar impurities. In this work, the effects of various surfactants such as CPC, CTMAC, LTMAC, SDS, AOT, Tween, PEG, and Triton were examined on the yield, purity, and phase separation time in micelle process. Among these surfactants, CTMAC (5%, w/v) gave the best result in terms of paclitaxel yield (${\sim}99%$), purity (${\sim}21%$), and phase separation time (30 min). The use of micelles in the pre-purification process allows for rapid and efficient separation of paclitaxel from interfering compounds and dramatically increases the yield and purity of crude paclitaxel for subsequent purification steps.