• Title/Summary/Keyword: powder preparation

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Powder Metallurgy of Tungsten Alloy

  • Ke, Zhang;Chun, Ge-Chang
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09b
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    • pp.1151-1152
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    • 2006
  • Preparation of tungsten powder, sorts of tungsten alloys and their application in economy are made a summary in this paper.

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Performance Evaluation of Prepackaged-Type Low Shrinkage Surface Preparation Materials Using a VA/E/MMA Terpolymer Powder

  • Hong, Sun-Hee;Kim, Wan-Ki
    • Journal of the Korea Institute of Building Construction
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    • v.12 no.1
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    • pp.64-72
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    • 2012
  • Recently, prepackaged-type surface preparation materials using redispersible polymer powders are widely used for interior and exterior finishing in the construction work. The purpose of this study is to evaluate the performance and the quality of prepackaged-type surface preparation materials using a VA/E/MMA terpolymer powder. Surface preparation materials using a VA/E/MMA terpolymer powder were prepared with shrinkage reducing agent contents of 0, 4 % and cellulose fiber contents of 0, 0.5, 1.0 %, and tested for drying shrinkage, strengths, adhesion in tension, crack and impact resistance, water absorption, permeability. As a result, prepackaged-type surface preparation materials show outstanding performance depending on the shrinkage reducing agent and cellulose fiber contents.

Preparation of Titanium Microfiltration Membrane by Field-flow Fractionation Deposition

  • Wang, QiangBing;Tang, HuiPing;Zhang, QianCheng;Qiu, QunFeng;Wang, JianYong
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.312-313
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    • 2006
  • The primary aim pursued by the preparation of separation membrane is the preparation of the membrane thin as well as with no defect. The field-flow fractionation deposition is a new molding technology which can overcome the traditional disadvantages such as multi-preparation to the preparation of great area of separation membrane with no defect. Therefor the mainly ingredients which influence the appearance and performance of titanium membrane layer are investigated by scanning electricity mirror (SEM) as well as porous material testing instrument: powder performance prepared and confected; selection of supporting body; sintering system such as temperature and time. It is shown that the membrane thickness can be controlled at $50{\mu}m$ or so; the filtration precision mainly rests with powder performance and selection of supporting body and little sintering system

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General Pharmacology of $^{13}C$-Urea Powder Preparation in ${Helikat}^{TM}$

  • Lee, Eun-Bang;Cho, Sung-Ig;Jung, Chun-Sik
    • Biomolecules & Therapeutics
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    • v.6 no.4
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    • pp.406-411
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    • 1998
  • The pre-mixed $_{13}C$-urea powder preparation in ${Helikit}_{TM}$ for test of Helicobacter pylori was evaluated for pharmacological properties. The oral doses of the preparation used in mice were 30-fold as compared to human doses. The results obtained in the present study demonstrate that spontaneous movement, hexobarbital-induced hypnosis, rotarod performance, body temperature, acetic acid-induced writhing syndrome, chemical and electroshock convulsion, pupil size and intestinal propulsion had not been affected at the oral doses of 230, 700 and 2100 mg/kg in mice. The blood pressure was slightly elevated as given intravenously in rats at a dose of 5 mg/kg of the preparation, but respiration was not influenced at the dose. In isolated guinea pig ileum and rat fundus preparation, the preparation at a concentration of $1{\times}10^{4}$ g/ml neither caused any direct effect nor inhibited the contraction produced by acetylcholine, histamine or 5-hydroxytryptamine. These results reported here provide evidence that pre-mixed $^{13}C$ 13/C-urea powder preparation is free of general pharmacological properties performed in oral administration.

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Revision Volume of Square-inch-spoon, Jeon-bi and Firmiana-Seed-sized Pill Preparations in 『Treatise on Cold Damage Diseases』 (『상한론』에서 산제의 방촌비와 전비, 환제의 오동자대 크기 수정치)

  • Kim, In-Rak
    • The Korea Journal of Herbology
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    • v.37 no.5
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    • pp.75-81
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    • 2022
  • Objectives : In 『Treatise on Cold Damage Diseases』, the volume of preparation dosage measured in Hap was 6.5mL. This study aimed to confirm that a square-inch-spoon, which measures powder preparation dosage, was 1/3 Hap, and that Jeon-bi was 1/8 square-inch-spoon. Based on these values, this study also aimed to adjust the diameter of Firmiana-Seed-sized pill preparation, currently known as 6.5mm, so that one square-inch-spoon of powder preparation creates 16 pills. Methods : Calculated the ratio between the floor areas of square-inch-spoon and Jeon-bi and measured the ratio of volume; assumed that powder preparations were stacked as much as possible in the shape of a square pyramid when scooped comfortably, then calculated the slopes of 1/3 Hap and 1/4 Hap; measured the volumes of powdered Oryeongsan and Lijungwhan in square-inch-spoon and Jeon-bi; created the powders into Firmiana-Seed-sized pill preparation; adjusted the diameter of Firmiana Seed so that 16 pills could be created. Results : Inferring from the floor areas, the volume of square-inch-spoon is 9.2 times that of Jeon-bi; one square-inch-spoon should be 1/3 Hap for the powder to reach its maximum slope of 47° and, according to actual measurement of powder preparations, reach its maximum volume; when created into Firmiana-Seed-sized pill preparations, one square-inch-spoon should be 1/3 Hap so that approximately 16 pills were created. Conclusions : One square-inch-spoon of powder preparation was 1/3 Hap(2.17mL), Jeon-bi was 1/8 square-inch-spoon(0.27mL), and the diameter of Firmiana-Seed-sized pill preparation was 5.5mm.

Preparation of AlN Powder by Combustion Reaction in the System of Al-AlN-NH4Cl (Al-AlN-NH4Cl 계에서 연소반응에 의한 AlN 분말의 제조)

  • Min, Hyun-Hong;Won, Chang-Whan
    • Journal of the Korean Ceramic Society
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    • v.43 no.7 s.290
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    • pp.445-450
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    • 2006
  • The preparation of AlN powder by SHS in the system of $Al-AlN-NH_4Cl$ was investigated in this study. In the preparation of AlN powder, the effect of gas pressure and the composition such as Al, AlF, and additive in mixture on the reactivity were investigated. At 60 atm of the initial inert gas pressure in reactor, the optimum composition for the preparation of pure AlN was 35 wt%Al+5 wt% $NH_4Cl+60wt%$AlN. The AlN powder synthesized in this condition was a single phase AlN with a whisker morphology.

High-throughput Preparation and Characterization of Powder and Thin-film Library for Electrode Materials

  • Fujimoto, Kenjiro;Onoda, Kazuhiro;Ito, Shigeru
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.254-255
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    • 2006
  • Powder library of pseudo four components Li-Ni-Co-Ti compounds were prepared for exploring the composition region with the single phase of the layer-type structure by using combinatorial high-throuput preparation system "M-ist Combi" based on electrostatic spray deposition method. The new layer-type compounds were found wider composition region than the previous report. This process is promising way to find multi component functional materials.

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Preparation of Ag Powder from AgNO3 by Wet Chemical Reduction Method1. The Establishment of Optimum Reaction System for the Preparation of Spherical Ag Powder (습식 화학적 환원법에 의한 AgNO3로부터 Ag 분말의 제조 1. 균일한 구형 Ag 분말의 제조를 위한 최적 반응계 확립)

  • Yuna, Ki-Seok;Park, Young-Chul;Yang, Beom-Seok;MIn, Hyun-Hong;Won, Chang-Whan
    • Journal of Powder Materials
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    • v.12 no.1
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    • pp.56-63
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    • 2005
  • Ag powder was prepared from $AgNO_3$ by wet chemical reduction method using various reduction agent system involving $AgNO_3$, $AgNO_2$(AgCl) and Ag complex ion aqueous solution. The pure Ag powder could be prepared regardless of reaction system but the particle shape and distribution were affected very much according to the kind of reduction agents and reaction systems. The optimum reaction system for the preparation of the silver powder having the uniform particle shape and size distribution was Ag complex ion aqueous solution-reduction agent system and in particular, $H_2O_2$ and $C_6H_8O_6$as a reduction agent leaded the more uniform particle shape and size distribution.