• Title/Summary/Keyword: Non-Formation

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Structural Properties of Polyaniline Blended with PNIPAM

  • Neupane, Kosh-Prasad;Ha, Jin-Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.4 no.3
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    • pp.209-213
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    • 2003
  • Polyaniline (PANi) composite particles were synthesized by chemical oxidation polymerization of aniline in presence of poly-n-isopropyl acryl amide (PNIPAM). The PANi particles formed in the reaction medium deposited onto non-conducting PNIPAM template to produce PANi-coated composite particles. The formation of composite was confirmed by FT-IR spectroscopy, and UV-VIS spectroscopy, and their morphological structures were examined by scanning electron microscopy (SEM). From the experimental results, it was determined that PANi was successfully coated onto non-conducting PNIPAM.

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An Efficient and Concise Synthesis of Biologically Interesting Natural Flemichapparin A, Flemingin A, Flemingin D, and Their Non-natural Analogues

  • Lee, Yong-Rok;Xia, Likai
    • Bulletin of the Korean Chemical Society
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    • v.28 no.9
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    • pp.1579-1584
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    • 2007
  • The efficient and concise synthesis of natural and non-natural pyranochalcones was achieved from readily available 2,4,5-trihydroxyacetophenone. The key steps in the synthetic strategy were ethylenediamine diacetate-catalyzed benzopyran formation and aldol reactions.

A Study on the Basic Tundish Coating Powder (Tundish Coating Powder의 염기성화에 관한 연구)

  • 정복환;김양훈;오양우;김성희
    • Journal of the Korean Ceramic Society
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    • v.20 no.4
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    • pp.283-288
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    • 1983
  • The properties of basic tundish coating powder were investigated comparing with acidic tundish coating powder especially in the corrosion resistance to the molten steel and the influence on non-metallic inclusion. The results show that the basic coating powder is superior to the acidic coating powder in corrosion resistance. It is appeared that the basic coating powder lining has less influence on the formation of non-metallic inclusions. These results will be promissing to reduce the coating thickness in tundish lining operation.

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Structural Properties of polyaniline blended with PNIPAM

  • Neupane, Kosh-Prasad;Ha, Jin-Wook
    • Proceedings of the KAIS Fall Conference
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    • 2003.06a
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    • pp.334-336
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    • 2003
  • Polyaniline(PANi) composite panicles were synthesized by chemical oxidation polymerization of aniline in presence of Poly-N-Isopropyl acryl amide(PNIPAM). The PANi panicles are formed in the reaction medium deposited onto non-conducting PNIPAM template to produce PANi-coated composite panicles. The formation of composite was confirmed by FT-IR spectroscopy, and UV-VIS spectroscopy, and their morphological structures were examined by scanning electron microscopy(SEM). From the experimental results, it was determined that PANi was successfully coated onto non-conducting PANIPAM.

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Influence of Nitrite and Ascorbic Acid on N-Nitrosamine Formation during Fermentation of Salted Anchovy (멸치젓 숙성중 아질산염과 아스코르브산이 N-Nitrosamine의 생성에 미치는 영향)

  • 김정균;이수정;성낙주
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.4
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    • pp.606-613
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    • 1997
  • The changes of contents in trimethylamine oxide nitrogen(TMAO-N), trimethylamine nitrogen(TMA-N), dimethylamine nitrogen(DMA-N), nitrite nitrogen(nitrite-N), nitrate nitrogen(nitrate-N) and the effect on the formation of N-nitrosamine(NA) during fermentation were investigated with salted anchovy added different amounts of sodium nitrite, sodium nitrate and ascorbic acid, respectively. When the sodium nitrite was added in salted anchovy, the contents of nitrite-N was decreased during fermentation . Whereas the formation of N-nitrosodimethylamine(NDMA ) was increased . Contents of TMAO-N was decreased, while TMA-N and DMA-N were increased during fermentation in all samples. Addition of ascorbic acid inhibited the formation of NDMA significantly. The formation of NDMA was inhibited by 81.3% at the concentration of 130mM as compared with non-added the control group. The aqueous model system was used for the evaluation of ascorbic acid(inhibitor) or thiocyanate (promoter) on the formation of NDMA using salt-fermented anchovy added with sodium nitrite. The optimum pH on the formation of NDMA was shown to be 3.8, and ascorbic acid inhibited the formation of NDMA whereas thiocyanate promoted. NDMA was not detected in the salt-fermented anchovy (control sample). However it is a possibility to form carcinogenic NDMA in stomach if both saltfer-mented anchovy and the materials contained abundant nitrite or nitrate were took in.

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Effects of Protein Unfolding and Soluble Aggregates Formation on the Gel Strength of Whey Proteins

  • Park, Moon-Jung;Michael E. Mangino
    • Preventive Nutrition and Food Science
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    • v.2 no.4
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    • pp.281-284
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    • 1997
  • Heat-induced gelation is an important functional property of whey proteins. Preheating of calcium reduced whey was reported to increase gel strength. 5% whey-protein solutions were preheated at pH7 and at various temperatures(60~8$0^{\circ}C$) for 15 minutes. The amount of soluble aggregates and denaturation enthalpy of preheated whey proteins were measured. Preheating temperature was negatively correlated with denaturation enthalpy($R^2$=0.857, P=0.08) and positive with the amount of soluble aggregates($R^2$=0.921, P=0.002). Denaturation enthalpy was negatively correlated with gel strength($R^2$=0.93, P=0.002). Soluble aggregates and gel strength were positively correlated($R^2$=0.972, P=0.0003). The formation of three dimensional gel network requires controlled protein denaturation and aggregation. Since preheating leads to the partial denaturation of proteins and the formation of soluble aggregates, preheated whey proteins have a higher gel strength than non-preheated one.

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Effect of Pressure on Acoustic Pressure Response and NO Formation in Diluted Hydrogen-Air Diffusion Flames (희석된 수소-공기 확산 화염에서 음향파 응답과 NO 생성에 미치는 압력의 영향)

  • Sohn, Chae-Hoon;Chung, Suk-Ho
    • 한국연소학회:학술대회논문집
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    • 1999.10a
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    • pp.11-20
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    • 1999
  • Acoustic pressure response and NO formation of hydrogen-air diffusion flames at various pressures are numerically studied by employing counterflow diffusion flame as a model flame let in turbulent flames in combustion chambers. The numerical results show that extinction strain rate increases linearly with pressure and then decreases, and increases again at high pressures. Thus, flames are classified into three pressure regimes. Such non-monotonic behavior is caused by the change in chemical kinetic behavior as pressure rises. Acoustic pressure response in each regime is investigated based on the Rayleigh criterion. At low pressures, pressure-rise causes the increase in flame temperature and chain branching/recombination reaction rates, resulting in increased heat release. Therefore, amplification in pressure oscillation is predicted. Similar phenomena are predicted at high pressures. At moderate pressures, weak amplification is predicted. Emission index of NO shows similar behaviors as to the peak-temperature variation with pressure.

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Structure and Formation of Diesel Fuel Spray

  • Fujimoto, Hajime;Dan, Tomohisa
    • Journal of ILASS-Korea
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    • v.1 no.4
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    • pp.8-20
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    • 1996
  • Research and development studies in internal combustion engines are set on a turning point due to requirements mostly purify the polluted environments. Naturally, basic studies concerned about engines are objected to elucidate formation mechanism of harmful matters, such as nitric oxide $(NO_x)$ and particulate matters. And for diesel engines, phenomenon in combustion chambers are analyzed in several approach ways in order to obtain detail understandings in closed and hardly observing space. In this article. it is discussed that the formation mechanism of diesel fuel sprays, mostly non-evaporating free diesel sprays. From that it would be promoted some new innovations in internal combustion engines of next generation.

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Three-Dimensional Pose Estimation of Neighbor Mobile Robots in Formation System Based on the Vision System (비전시스템 기반 군집주행 이동로봇들의 삼차원 위치 및 자세 추정)

  • Kwon, Ji-Wook;Park, Mun-Soo;Chwa, Dong-Kyoung;Hong, Suk-Kyo
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.12
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    • pp.1223-1231
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    • 2009
  • We derive a systematic and iterative calibration algorithm, and position and pose estimation algorithm for the mobile robots in formation system based on the vision system. In addition, we develop a coordinate matching algorithm which calculates matched sequence of order in both extracted image coordinates and object coordinates for non interactive calibration and pose estimation. Based on the results of calibration, we also develop a camera simulator to confirm the results of calibration and compare the results of simulations with those of experiments in position and pose estimation.

A ROBUST METHOD MINIMIZING DIGITIZATION ERRORS IN SKELETONIZATION OF THREE DIMENSIONAL BINARY SEGMENTED IMAGE

  • Shin, Hyun-Kyung
    • Journal of applied mathematics & informatics
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    • v.15 no.1_2
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    • pp.425-434
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    • 2004
  • Pattern recognition in three dimensional image is highly sensitive to assigned value and formation of voxels (pixels for two dimension case). However, occurred while digital imaging, digitization error leads to unpredictable noises in image data. Skeletonization, a powerful tool of pattern recognition, is sensitively dependent on boundary formation. Without successful controlling of the noises, the results of skeletonization can not be allowed as a stable solution. To minimize the effect of noises affecting to boundary formation, we developed a robust processing method useful in skeletonization technique for pattern recognition. Finally, we provide rigorous test results achieved throughout simulation on analytic three dimensional image.