• 제목/요약/키워드: Non-Formation

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분자동역학 전산모사를 이용한 박막의 불안정성 및 나노 구조물 형성에 관한 연구 (Instability of Nanoscale Thin Film;a Molecular Dynamics Study)

  • 한민섭;이준식;박승호;최영기
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.228-232
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    • 2003
  • It has recently been shown that the instability of thin film of a nanoscale can be used in the processes of building nano-size structures, which have potential practical importance in nanotechnology. Molecular dynamics simulation is conducted to probe the thin fluid film of a nano-size and its dynamic behavior during destabilization and structure formation. Non-continuum characteristics are shown in the properties like pressure tensor, viscosity, and thermal conductivity. The thermocapillary force induces a slow growth of long waves in the scale considered. A long-range interaction with the solid wall induces vertical structures, whose formation time and space between neighbors are proportional to the strength of the interaction.

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차 향기의 생성 메커니즘 (Formation Mechanism of Aroma Compound during Tea Manufacturing Process)

  • 조미자;조기정;최현숙;최두복;조기안;조훈
    • KSBB Journal
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    • 제31권2호
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    • pp.91-99
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    • 2016
  • Tea is an aqueous infusion of dried leaves of the plant Camellia sinensis L. and is the second most widely consumed beverage around the world after water. Aroma compounds of tea differ largely depending on the manufacturing process, even from the same categories of different origins. The flavor of tea can be divided into two categories: taste (non-volatile compounds) and aroma (volatile compounds). In the present study, we review the formation mechanism of main aromas generated from carotenoids, lipids, glycosides as precursors, and Maillard reaction during the tea manufacturing process, with biological and chemical mechanisms.

청주 구도심 지역의 가로·가구·필지체계의 형성과 변천 (Formation and Change of Road·Block·Lot System of Old Inner Cheongju City)

  • 원세용;김태영
    • 한국농촌건축학회논문집
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    • 제5권2호
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    • pp.10-19
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    • 2003
  • The purpose of this study was to analyze the formation and change of road-block-lot of the old inner city in cheongju The result of this study are as follows; (I)Among others a system roads of in around the old castle in cheongju city is most of feature north and south direction of road. Lot system is organic relations of north and south direction of road. Therefore, urban tissue in around the old castle in cheongju city is established order road system keep on the change of expansion urban tissue. (2) Block type classified into non-division, 2division and over 3division. (3) The square block remains mostly in Cheongju old castle, two-division block was around south of castle. And block of the grid-form street system divided into over 3 division. Through the guideline about characteristic of block type, residential area should be developed as a characteristics area in the urban area.

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환상박피와 적심이 '세계일' 사과의 조기낙과에 미치는 영향 (Effects of Girdling and Pinching on the June Drop of 'Sekaiichi' Apple)

  • 최석원;김규래
    • 원예과학기술지
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    • 제18권3호
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    • pp.391-394
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    • 2000
  • 사과 '세계일' 품종에 대한 조기낙과 방제를 목적으로 환상박피, 환상박피+적심 및 적심처리를 실시한 결과 환상박피와 환상박피+적심 처리구가 조기낙과를 현저히 억제하고 과실 비대생장을 촉진하였다. 환상박피+적심 및 적심 처리구는 과대지의 생장을 억제하였다. 다음해의 화아 분화율은 처리구간에 차이가 뚜렷하지 않았다. 환상박피의 적기는 만개 전 5일경부터 만개기 사이인 것으로 추정되었다.

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Determination of Stability Constants Using Electrochemical Methods for the Complex Formation of Platinum and Palladium with Polyelectrolytes

  • Park, Joon Seo;Chung, Koo Soon
    • 분석과학
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    • 제8권4호
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    • pp.691-698
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    • 1995
  • The complexation of platinum and palladium with synthetic polyelectrolytes was studied. The successive and overall stability constants of Pd(II) with PEI and 2PVP were obtained by potentiometric titration. Because of the slow equilibrium time, the potentiometric titrations were performed using the home-made automatic titrator in order to analyze the complexations according to the modified Bjerrum method. The complex formation constant of Pt(IV) with 2PVP, measured by differential pulse polarography, was calculated from the peak currents that were obtained in non-complexing media and in solution containing 2PVP.

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Gas Inflow from the Central Few Hundred Parsec to the Few Parsec Regions

  • 이안선;김성수
    • 천문학회보
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    • 제36권2호
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    • pp.56.1-56.1
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    • 2011
  • We investigate the hydrodynamics of gas clouds in the central few hundred parsecs of the Galaxy. Non-axisymmetry (elongation) of the Galactic bulge can form a reservoir of dense molecular clouds at around two hundred parsecs from the center through the X1-X2 orbit transfer, and the star formation that has been sustained for the lifetime of the galaxy can build up a nuclear bulge there. If the nuclear bulge is elongated, this again can transport the gas there down to the central few parsecs region. We perform a series of 3-D hydrodynamic simulations that consider a potential for this "nested bar", cooling/heating, star formation and supernova feedback, and estimate the efficiency of the gas inflow down to the central parsec region.

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Development of a New Cosmological Hydro Simulation Code

  • 김주한;신지혜;김성수;박창범
    • 천문학회보
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    • 제36권2호
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    • pp.52.1-52.1
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    • 2011
  • We have implemented the Smoothed Particle Hydrodynamics (SPH) into the cosmological N-body simulation code. The pre-initial particle distribution is set to follow the glacial conditions and the initial temperature of hydro particles is calculated based on the adiabatic process in the expanding backgrounds. Typical adiabatic SPH equations are adopted and, additionally, non-adiabatic processes such as heating/cooling and supernova explosion are added. We study the effect of star formation criteria on the global star formation rate and compare it with the observations.

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액적의 액막 충돌에 대한 수치해석 (A Numerical Analysis of a Drop Impact on the Liquid Surface)

  • 이상혁;허남건;손기헌
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.2568-2573
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    • 2008
  • A drop impact on the liquid film/pool generates several phenomena such as the drop floating, bouncing, formation of vortex ring, jetting, bubble entrapment and splashing. These phenomena depend on the impact velocity, the drop size, the drop properties and the liquid film/pool thickness. These parameters can be summarized by four main dimensionless parameters; Weber number, Ohnesorge number, Froude number and non-dimensional film/pool thickness. In the present study, the phenomena of the splashing and bubble entrapment due to the drop impact on the liquid film/pool were numerically investigated by using a Level Set method for the sharp interface tracking of two distinct phases. After the drop impact, the splashing phenomena with the crown formation and spreading were predicted. Under the specific conditions, the bubble entrapment at the base of the collapsing cavity due to the drop impact was also observed. The numerical results were compared to the available experimental data showing good agreements.

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담배와 무 Peroxidase Isozyme들의 세포 생화학적 연구: 조직 특이성 발현과의 연관성 (Studies on Peroxidase Isozymes of Tobacco and Korean Radish: implication of Specific Isoperoxidase in Shoot Formation)

  • 김승수
    • 한국식물학회:학술대회논문집
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    • 한국식물학회 1987년도 식물생명공학 심포지움 논문집 Proceedings of Symposia on Plant Biotechnology
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    • pp.357-389
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    • 1987
  • In an attempt to clarify the physiological functions of individual isoperoxidases, we have studied enzymatic and immunological properties as well as cellular distribution of isoperoxidases from tobacco callus and Korean radish. The gene expression patterns of isoperoxidases in shoot and non-shoot-forming tobbaco callus were also examined by rabbit reticulocyte lysatein vitro translation system. These results indicate that fraction of translatable poly(A)-isoperoxidase mRNA was increased considerably in shoots. At the present time, at least 6-7 isoperoxidases could be detected from the translation mixture of total cellular RNA, among which only one cell wall localized anodic isoperoxidase (named A3) mRNA was bimorphic mRNA. These data suggest the possible regulation of peroxidase activity during shoot formation by altering the polyadenylation state of mRNA. In case of Korean radish seedlings, poly(A)- peroxidase mRNA were also increased depending upon aging.

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In vitro Formation of Tuberous Roots from Root Ends in the Rooted Tuberous stem without shoots in Cyclamen persicum MILL.

  • Lim, Jong-Gu;Junzo, Fujigaki
    • Plant Resources
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    • 제7권3호
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    • pp.222-225
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    • 2004
  • In Japan, propagation of cyclamen is mainly from seedlings. However, seeds are expensive and germination is slow and non..uniform. Therefore, to achieve genetically uniform propagation, multiplication must be vegetative. The rooted tuberous stems without shoots as sources of explants were cultured on the media containing BA and sucrose. After 30 days cultivation, tuberous roots were produced from the root ends attached to a tuberous stem and its capability was dependent on the type of media. The highest percentage of tuberous root formation was observed in Culture on the medium of 1/3 MS containing 0.05mgL$^{-1}$ NAA, 0.5mg L$^{-1}$ BA and 5% sucrose. Growth rates of the tuberous roots were greatly influenced by the cutting positions of a root in explants. The highest growth of was observed if small amount of root end was cut at initiation of tissue culture.

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