• 제목/요약/키워드: gamma type

검색결과 1,063건 처리시간 0.025초

$Ni/{\gamma}-Al_2O_3/Metallic$ device를 이용한 고온 태양열 메탄-이산화탄소 개질반응 (Solar $CO_2$ Reforming of Methane Using $Ni/{\gamma}-Al_2O_3/Metallic$ foam device)

  • 신일융;이주한;이진규;서태범
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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    • pp.275-281
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    • 2011
  • Solar reforming of methane with $CO_2$ was successfully tested with a direct irradiated absorber on a parabolic dish capable of $5kW_{th}$ solar power. The new type of catalytically activated metallic foam absorber was prepared, and its activity was tested. Ni was applied as the active metal on the gamma - alumina coated Ni metal foam for the preparation of the catalytically-activated metal foam layer. Compared to conventional direct irradiation of the catalytically-activated ceramic foam absorber, this new metallic foam absorber is found to exhibit a superior reaction performance at the relatively low insolation or at low temperatures. In addition, unlike direct irradiation of the catalytically-activated ceramic foam absorber, metallic foam absorber has better thermal resistance, which prevents the emergence of cracks caused by mechanical or thermal shock. The total solar power absorbed reached up to 2.1kW and the maximum $CH_4$ conversion was almost 40%.

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랫트 배양 신경교세포의 성장 및 분화에 대한 Cytokine의 효과 (Effect of Cytokines on the Growth and Differentiation of the Glial Cells from Rat Brain in Culture)

  • 김혜경;윤용하;강신정;박찬웅;김용식
    • 대한약리학회지
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    • 제32권2호
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    • pp.177-188
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    • 1996
  • The effects of cytokines on the growth and differentiation of glial cells in culture were evaluated to confirm that cytokines could modify the number and function of glial cells. Proliferation of glial cells was determined by the $^3H-thymidine$ uptake and the double immunostain with anti-cell specific marker and anti-bromodeoxyuridine(BrdU) antibody. To check the effect on the differentiation of glial cells, the amount of glial fibrillar acidic protein(GFAP) and the activity of glutamine synthetase(GS) were measured in astrocytes. And also the amounts of myelin basic protein(MBP) and the activity of 2',3'-cyclic nucleotide phosphohydrolase(CNPase) were measured in oligodendrocytes. Among the cytokines used, only interleukin-$1{\beta}(IL-1{\beta})$ stimulated the growth of type 1 and type 2 astrocyte as well as 0-2A precursor cell. When the functional changes in these glial cells by cytokines were tested, $IL-1{\beta}$ did not increase GFAP content in type 1 and type 2 astrocyte, but $IL-1{\beta}$ increased GS activity in type 1 astrocyte, and slightly decreased this enzyme activity in type 2 astrocyte. Also interleukin-2(IL-2) and $interferon-{\gamma}$ $(IFN-{\gamma})$ inhibited the activity of GS in type 1 and type 2 astrocyte. On the other hand, all cytokines used did not modify the growth and differentiation in oligodendrocytes. From these results we could suggest that $IL-1{\beta}$ increases the growth of type 1 and type 2 astrocyte and also promotes the development for 0-2A precursor cell to type 2 astrocyte.

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저선량 ${\gamma}$ 선 조사가 배추와 무 종자의 발아와 양분흡수에 미치는 영향 (Effects of low dose ${\gamma}$ radiation on the uptake of mineral nutrients in chinese cabbage and radish)

  • 윤영만;김남범;김재성;김정규
    • 한국환경농학회지
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    • 제18권4호
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    • pp.344-348
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    • 1999
  • 배추와 무의 영양생리에 대한 저선량${\gamma}$선에 의한 자극작용의 영향을 파악하고자 1998년산 흑진주배추, 1995년산 서림엇갈이배추, 1998년산 청운무 종자에 1에서 10Gy의 저선량 ${\gamma}$선을 조사하고 생육시기에 따른 생장량과 무기양분의 변화를 분석하였다. 공시된 배추품종들은 조사선량의 증가에 따라서 발아율과 건물생산량이 증가하는 경향을 보였다. 건물생산의 증가는 흑진주배추에서 가장 현저하여 10Gy 처리구에서 143%로 증가되었고, 서림엇갈이배추는 10Gy에서 138%로 증가하였다. 청운무는 ${\gamma}$선 조사에 따른 발아율과 건물생산량의 일관된 경향성을 보이지 않았다. 무기영양소들의 함량변화는 선량-반응 곡선의 ${\gamma}$ 또는 ${\delta}$형을 나타내 ${\gamma}$선에 의한 자극효과가 일부처리구에서 나타나기는 하였지만 일반적 현상이라고 인정하기 어려웠다. 따라서 저선량 ${\gamma}$조사가 배추와 무의 영양생리에 미치는 영향을 정확하게 파악하기 위한 연구결과의 집적이 필요할 것으로 판단된다.

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OSCILLATION AND NONOSCILLATION CRITERIA FOR DIFFERENTIAL EQUATIONS OF SECOND ORDER

  • Kim, RakJoong
    • Korean Journal of Mathematics
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    • 제19권4호
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    • pp.391-402
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    • 2011
  • We give necessary and sufficient conditions such that the homogeneous differential equations of the type: $$(r(t)x^{\prime}(t))^{\prime}+q(t)x^{\prime}(t)+p(t)x(t)=0$$ are nonoscillatory where $r(t)$ > 0 for $t{\in}I=[{\alpha},{\infty})$, ${\alpha}$ > 0. Under the suitable conditions we show that the above equation is nonoscillatory if and only if for ${\gamma}$ > 0, $$(r(t)x^{\prime}(t))^{\prime}+q(t)x^{\prime}(t)+p(t)x(t-{\gamma})=0$$ is nonoscillatory. We obtain several comparison theorems.

O-(p-Aminosalicylyl)-inositol류의 합성과 항균시험 (Sythesis of O-(p-Aminosalicylyl)-inositols and Their Antibacterial Test)

  • 박정섭
    • 미생물학회지
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    • 제12권2호
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    • pp.85-93
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    • 1974
  • Four stereoisomers of inositol p-aminosalicylate, that is hexaris-O-(p-aminosalicylyl)-myo-inositol, hexaris-O-(p-aminosalicylyl)-muco-inositol were synthesized by p-aminosalicylyl chloride with myo-, epi-, scyllo-, and muco-inositol respectively. Their antibacterial activity was tested against human type tubercle bacilli $H_{37}$/Rv, in contrast to 1.25.gamma./ml of p-aminosalicylic acid used as control. Hexaris-O-(p-aminoslicylyl)-muco-inositol showed the strongest antibacterial action at 0.625.gamma./ml, the other compounds more or less active than p-aminosalicylic acid.

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ON THE STABILITY OF FUNCTIONAL EQUATIONS IN n-VARIABLES AND ITS APPLICATIONS

  • KIM, GWANG-HUI
    • 대한수학회논문집
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    • 제20권2호
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    • pp.321-338
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    • 2005
  • In this paper we investigate a generalization of the Hyers-Ulam-Rassias stability for a functional equation of the form $f(\varphi(X))\;=\;\phi(X)f(X)$, where X lie in n-variables. As a consequence, we obtain a stability result in the sense of Hyers, Ulam, Rassias, and Gavruta for many other equations such as the gamma, beta, Schroder, iterative, and G-function type's equations.

SYNTHESIS OF BLOCK COPOLYMERS CONTAINING POLYPEPTIDE AND ITS BIOMEDICAL APPLICATION

  • Cho, Chong-Su
    • 한국잠사학회:학술대회논문집
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    • 한국잠사학회 1997년도 Progress and Future Development of Sericultural Science and Technology 40th Anniversary Commemoration Symposium
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    • pp.159-169
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    • 1997
  • ABA-type(or AB) block copolymers composed of poly(${\gamma}$-alkyl L-glutamate) (PALG)[or poly(L-leucine)] as the A component and polyether[or poly (N-isopropy1 acrylamide) as the B component were synthesized by polymerization of (${\gamma}$-alkyl L-glutamate N-carboxyanhydride initiated by primary amined located at both(or one) ends of the polymer chains. Structural studies of the block copolymers were performed in the solution and solid state. Also, artificial skin, drug delivery system of the block copolymers and cell attachment onto the copolymer were carried out for biomedical applications.

GENERATING FUNCTIONS FOR THE EXTENDED WRIGHT TYPE HYPERGEOMETRIC FUNCTION

  • Jana, Ranjan Kumar;Maheshwari, Bhumika;Shukla, Ajay Kumar
    • 대한수학회논문집
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    • 제32권1호
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    • pp.75-84
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    • 2017
  • In recent years, several interesting families of generating functions for various classes of hypergeometric functions were investigated systematically. In the present paper, we introduce a new family of extended Wright type hypergeometric function and obtain several classes of generating relations for this extended Wright type hypergeometric function.

APPROXIMATE PEXIDERIZED EXPONENTIAL TYPE FUNCTIONS

  • Lee, Young-Whan
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제19권2호
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    • pp.193-198
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    • 2012
  • We show that every unbounded approximate Pexiderized exponential type function has the exponential type. That is, we obtain the superstability of the Pexiderized exponential type functional equation $$f(x+y)=e(x,y)g(x)h(y)$$. From this result, we have the superstability of the exponential functional equation $$f(x+y)=f(x)f(y)$$.

STABILIZATION FOR THE VISCOELASTIC KIRCHHOFF TYPE EQUATION WITH A NONLINEAR SOURCE

  • Kim, Daewook
    • East Asian mathematical journal
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    • 제32권1호
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    • pp.117-128
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    • 2016
  • In this paper, we study the viscoelastic Kirchhoff type equation with a nonlinear source $$u^{{\prime}{\prime}}-M(x,t,{\parallel}{\bigtriangledown}u(t){\parallel}^2){\bigtriangleup}u+{\int}_0^th(t-{\tau})div[a(x){\bigtriangledown}u({\tau})]d{\tau}+{\mid}u{\mid}^{\gamma}u=0$$. Under the smallness condition with respect to Kirchhoff coefficient and the relaxation function and other assumptions, we prove the uniform decay rate of the Kirchhoff type energy.