• Title/Summary/Keyword: rapid preparation

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Preparation for Porous Ceramics Using Low Grade Clay (저급점토를 이용한 다공성 세라믹스 제조)

  • 한상목;신대용;강상규
    • Journal of the Korean Ceramic Society
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    • v.35 no.6
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    • pp.575-582
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    • 1998
  • Sutiability of Jungsan clay shale dolomite sludge Anyang feldspar and alumina as raw materials for light-weight porous ceramics was examined. In order to find optimum manufacturing conditions compositions heating temperatuers and heating times were varied and their effects on physical properties were measured and bloating mechanism was investigated. Jungsan clay seems suitable as raw material to make the light-weight constructional materials with 5wt% of ANyang feldspar and alumina added in calcined clay (800$^{\circ}C$) having bulk density of 0.45g/cm3 water absorption of 1.34% and compressive strength of 85kg/cm2 rapid-heated at 1200$^{\circ}C$ for 30min. It is suggested that bloating mechanism depends on the difference of tem-peratures between the inside and outside in specimen the remained gases in interstices can bloat by the li-quid phase of surface with high viscosity and gas pressure at elevated temperature.

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Preparation of Polysilicon for Solar Cells (태양전지용 폴리실리콘 제조)

  • Kim, Hee Young
    • Korean Chemical Engineering Research
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    • v.46 no.1
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    • pp.37-49
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    • 2008
  • Recent rapid progress in the photovoltaic industry has seriously been retarded by limited supply of polysilicon used as the feedstock for silicon wafer-based solar cells. It is thus believed that development of a competitive process for preparing polysilicon with the quality required for solar cells can greatly enhance the competitiveness and extent of the photovoltaic application. Technologies currently available for preparing the silicon feedstock are reviewed with the recent fluidized bed silicon deposition process being discussed in more details in terms of key technical barriers.

A Simple and Reliable Method for Preparation of Cross-Contamination-Free Plant Genomic DNA for PCR-Based Detection of Transgenes

  • Hwang, Seon-Kap;Kim, Young-Mi
    • BMB Reports
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    • v.33 no.6
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    • pp.537-540
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    • 2000
  • A simplified but reliable method was developed for the polymerase chain reaction (PCR)-based detection of genetically modified (GM) plants. The modified CTAB (mCTAB) method enabled us to prepare a high quality of genomic DNA from several hundred plant leaf samples in one day. Using DNA samples prepared from seven dicots and two monocots, approximately 1.75-kb regions spanning 17 S to 25 S ribosomal RNA genes were successfully amplified in a 2X PCR pre-mix containing BLOTTO. Further fidelity assessment of the mCTAB method by PCR analysis with Roundup Ready soybean (RRS) and non-RRS plants showed that the DNA samples prepared alternately from each of two lines were evidently free of cross-contamination. These results demonstrate that the mCTAB method is highly recommended for the rapid detection of transgenes in large numbers of leaf samples from diverse transgenic plants.

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Shift in Warfare Paradigm and Military Transformation (전쟁패러다임의 전환과 군사변혁)

  • Jeong, Chun-Il
    • Journal of National Security and Military Science
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    • s.4
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    • pp.381-418
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    • 2006
  • In present, advanced countries in the world are seen concentring on Military Transformation to create new military capability as there is a shift in Warfare Paradigm. Rapid development of technology enables military system, operational concept and organization innovated. As a result, Revolution in Military Affairs(RMA) that dramatically increased warfighting capability is pursued. Especially, advanced information technology constructs system of systems with abilities of battle visualization, information sharing in battlefield, long-range strike capability that are interoperable and combined. Corresponding to this, engagement methods and organizations are being progressively developed. The purpose of this thesis is overview of newly developing Warfare Paradigm and analysis of tendency of Military Transformation that advanced countries are pursuing preparation to this. Above all, specific aspects and contents of the Warfare Paradigm which emerged by information age were summarized. Subsequently, Military Transformation which provides the basic concepts and principles to the advanced countries in the world for the creation of new military capability was discussed. In conclusion, the tendency of Military Transformation by U.S.A, Japan, China, and Russia surround the Korean peninsular as the major power in military was carefully observed.

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Benzylic Brominations with N-Bromosuccinimide in 1,2-Dichlorobenzene: Effective Preparation of (2-Bromomethyl-phenyl)-Methoxyiminoacetic Acid Methyl Ester

  • Lee, Sanghyuck;Ra, Choon Sup
    • Clean Technology
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    • v.22 no.4
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    • pp.269-273
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    • 2016
  • The benzylic bromination of methoxyimino-o-tolyl-acetic acid methyl ester (1) into (2-bromomethyl-phenyl)-methoxyimino-acetic acid methyl ester (2) using N-bromosuccinimide in the presence of 2,2'-azobisisobutyronitrile in various reaction solvents were investigated. The efficiency of the reaction was found to be sensitive to the kind of reaction solvents. We found the benzylic bromination of 1 to 2 can be performed in 1,2-dichlorobenzene as reaction solvent superior to the classic Wohl-Ziegler procedure in both reaction time and isolated yield (8 h vs 12 h, 92 vs 79%). This system provides clean, rapid, and high-yielding reactions with replacement of conventional solvents, such as tetrachloromethane, by less-toxic 1,2-dichlorobenzene.

A Study on the Competitiveness Evaluation of Korean Automobile Manufacturing (한국 자동차 생산의 경쟁력 평가)

  • 장문철
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.20 no.43
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    • pp.393-408
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    • 1997
  • In the early 1990s, as Korean automobile industry has made rapid progress due to favorable trend in domestic demand and steady increase of export it is very important to analyze the extents of competitiveness and the trends of change in the field of production. In this dissertation, the current situation of our competitiveness and its changes in the field of production are synthetically reviewed through examining productivity and quality, that is output, as well as other overall factors related in the process of production. And this analysis reassures that first of all, our prior tasks lie in the quality and volume of production, and we should develope competitiveness through multilateral innovation of management Now in order to meet these prior tasks, we must secure our own technology design and ability for innovaton ; enlarge overseas local production technical tie-up with leading companies and develop M&A for globalization ; improve price competitiveness, construct cooperation of labor and capital, and improve the structure of finance for innovation of management saving the cost ; establish the new method of production for the preparation of increasing overseas investment in near future.

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Spectrophotometric Determination of Phenothiazine Derivatives by using Picric acid as Electron Acceptor (Picric acid를 전자수용체로 한 Phenothiazine계 화합물의 정량법)

  • 옥치완;신태용
    • YAKHAK HOEJI
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    • v.31 no.5
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    • pp.322-329
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    • 1987
  • A rapid and sensitive spectrophotometric method has been developed for quantitation of some phenothiazine derivatives (PTZDS). The method depends on the formation of insoluble yellow complexes between PTZDS and picric acid (PCA) in aqueous layer. These complexes are quantitatively extracted from aqueous phase into chloroform. The binding ratio of PTZDS-PCA complexes were presumed as PTZDS-1 to PCA-1 by means of mole ratio and continuous variation methods. The complexes are stable for more than 24hours in chloroform layer at room temperature. Most of compounds associated with pharmaceutical preparation of PTZDS do not interfere with this method. However, chlorpheniramine and diphenhydramine interfere with the riaethod. The binding state of PTZDS-PCA complexes were presumed by IR and $^1$H-NMR spectra as intermolecular hydrogen bonding.

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A study on the Construction for the u-safe Korea System (유비쿼터스 기술 기반의 재난관리시스템 "u-safe Korea" 개발 구상)

  • Yi, Waon-Ho;Kim, Hyun-Ju;Park, Sang-Hyun;Jung, Tae-Ho
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.131-134
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    • 2008
  • Increasing the need of national safety management system in order to an epoch-making improvement to scientific disaster management which appears new types of disasters through the exchange of traditional disaster environment and responds actively to the rapid exchange of social environment based on u-IT. Requiring the development of systematical information sharing networking system and sharing realtime data amongst government, local authorities and related organisations under both safety management in normal times and circumstance management in disaster times, and need for the establishment of national safety strategy, which has been strengthened function such as prevention and preparation. This research provides a basic scheme and strategic tasks in order to constitute preventing scientific national disaster prevention structure at anytime and anywhere from disaster which is based on ubiquitous technology and realise the intelligent national disaster prevention system of u-safe Korea.

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Preparation of $TiO_2$ Pure Nanoparticles by Vapor-Phase Hydrolysis (기상 가수분해에 의한 순수 $TiO_2$ 초미립자의 제조)

  • Lee, Soo-Keun
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.9 no.1
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    • pp.11-18
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    • 2003
  • The pure $TiO_2$ particles have been prepared in vapor-phase hydrolysis of titanium tetraisopropoxide(TTIP). The rate of TTIP hydrolysis was so fast that the overall rate of formation of $TiO_2$ was controlled by the rate of mixing of TTIP and $H_2O$. Thus, the primary $TiO_2$ particles were prepared in nano sizes to form chainlike aggregates due to rapid coagulation. The pure $TiO_2$ particles as prepared were amorphous at the reactor set temperatures below $400^{\circ}C$ and became anatase at the temperatures of $450^{\circ}C$ above while the weak rutile peaks were also observed above $800^{\circ}C$. The actual size of primary particles as prepared were reduced by increasing the reactor set temperature while their crystalline sizes as well as BET sizes increased by post-sintering.

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