• 제목/요약/키워드: C-S-H

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Sulfurization of Rare-Earth Oxides Using $H_2S$ and $SC_2$

  • Sato, Nobuaki;Sato, Soichi
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2004년도 Proceedings of the 4th Korea-China Joint Workshop on Nuclear Waste Management
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    • pp.60-63
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    • 2004
  • Sulfurization of rare-earth oxides R203 (R=Nd, Eu) using sulfurizing reagents, such as $H_2S$ and $SC_2$was examined for the sulfide magnetic separation of spent fuel. $EU_2O_3$was found to react with H$_3$S gas forming the mixture of $EU_2O_2S$ and EuS at 500 oC, while EuS was formed by $SC_2$ at 800 oC. In the case of the mixture of $R_2O_3$and $UO_2$, EuS and $ND_3S_4$ were formed as well as $EU_2O_2S$ and $Nd_2O_2S$ at 500oC in $H_2S$, though $UO_2$ remained unreacted.

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THE GROWTH OF GaN/POROUS-Si USING BY MEB

  • Park, S.H.;Chi, C.S.;Park, C.S.;Lee, C.M.;Yang, S.J.;Jung, W.H.;Kang, T.W.;Yoon, G.S.;Kim, C.O.;Eom, G.S.
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 1998년도 IUMRS-ICEM ABSTRACT BOOK
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    • pp.94.1-94
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    • 1998
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Cu(II) Hexafluoroacetylacetonate 프리커서에 의한 구리 화학증착의 열역학적 평형조성 해석 (Thermodynamic Equilibrium Analysis of Copper Chemical Vapor Deposition from Cu(II) Hexafluoroacetylacetonate Precursor)

  • 전치훈;김윤태;백종태;유형준;박동원;최병진;김대룡
    • 한국재료학회지
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    • 제5권6호
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    • pp.657-666
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    • 1995
  • Cu(hfac)$_2$,(Cu(II) hexafluoroacetylacetonate)를 프리커서로 하는 구리 화학증착에 대해 자유에너지 최소화법으로 열역학적 평형조성 계산을 수행하였다. Cu(hfac)$_2$-Ar계의 경우Cu(hfac)$_2$ 프리커서 자체의 열분해로부터 모든 공정조건에서 증착박막내로의 탄소 출입이 관찰되었다. Cu(hfac)$_2$-H$_2$,계에서는 Cu(hfac)$_2$-Ar계보다 낮은 온도에서 구리박막이 증착되며, H$_2$입력비 및 반응온도의 증가에 따라 응축상의 석출형태는 C(s)+CuF(s)로부터 C(s)+CuF(s)+Cu(s), C(s)+Cu(s), Cu(s), C(s)의 순으로 변화되는 것으로 나타났다.

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Synthesis of Cubic Boron Nitride by Al-Mg Solvents

  • Park, Jong-Ku;Park, S.T.;S.K. Singhal;S. J. Cui;K. Y. Eun
    • The Korean Journal of Ceramics
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    • 제3권3호
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    • pp.187-190
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    • 1997
  • The aluminum-magnesium (Al-Mg) aklloys have been proved to be an effective solvent for synthesis of cubic-phase boron nitride (cBN) from hexagonal-phase boron nitride (hBN) at the conditions of high pressures and high temperatures (HP/HT). Various kinds of hBN powders having different crystallinity have been tested for cBN synthesis with Al-Mg solvents. The conversion ratio from hBN to cBN and the shape of synthesized cBN crystals appeared to be affected strongly by chemical composition and added amount of Al-Mg solvents as well as crystallinity of BN powders. As the magnesium content increased in the Al-Mg solvents, the conversion ratio increased and the size of cBN crystals became larger. The crystal facets developed well in the specimens with solvents having high Mg content. It was observed that a hBNlongrightarrowcBN transformation occurred more easily in the specimens having well crystallized hBN powders. Amorphous BN having much $B_2O_3$ impurity exhibited a low threshold temperature for transformation to cBN, which was attributed to crystallization of amorphous BN to well crystallized hBN prior to transformation into cBN with help of $B_2O_3$.

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Evidence for galaxy dynamics tracing background cosmology below the de Sitter scale of acceleration

  • van Putten, Maurice H.P.M
    • 천문학회보
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    • 제42권2호
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    • pp.55.5-56
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    • 2017
  • Galaxy dynamics probes weak gravity at accelerations below the de Sitter scale of acceleration adS = cH, where c is the velocity of light and H is the Hubble parameter. Low and high redshift galaxies hereby offer a novel probe of weak gravity in an evolving cosmology, satisfying H(z) = H0(1 + A(6z + 12z^2 +12z^3+ 6z^4+ (6/5)z^5)/(1 + z) with baryonic matter content A sans tension to H0 in surveys of the Local Universe. Galaxy rotation curves show anomalous galaxy dynamics in weak gravity aN < adS across a transition radius r beyond about 5 kpc for galaxy mass of 1e11 solar mass. where aN is the Newtonian acceleration based on baryonic matter content. We identify this behavior with a holographic origin of inertia from entanglement entropy, that introduces a C0 onset across aN=adS with asymptotic behavior described by a Milgrom parameter satisfying a0=omega/(2pi), where omega=sqrt(1-q)H is a fundamental eigenfrequency of the cosmological horizon. Extending an earlier confrontation with data covering 0.003 < aN/adS < 1 at redshift z about zero in Lellie et al. (2016), the modest anomalous behavior in the Genzel et al. sample at redshifts 0.854 < z <2.282 is found to be mostly due to clustering 0.36 < aN/adS < 1 close to the C0 onset to weak gravity and an increase of up to 65% in a0.

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Preparation of [C60]Fullerene-CoS2 Nanocomposites and Kinetics Study for Photocatalytic Degradation of Organic Dyes

  • Kim, Jae Jin;Ko, Weon Bae
    • Elastomers and Composites
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    • 제51권1호
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    • pp.49-55
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    • 2016
  • Nanosized cobalt disulfide ($CoS_2$) particles were synthesized with 0.08 M cobalt chloride hexahydrate ($CoCl_2{\cdot}6H_2O$) and 0.2 M sodium thiosulfate pentahydrate ($Na_2S_2O_3{\cdot}5H_2O$) dissolved in distilled water under microwave irradiation. $[C_{60}]Fullerene-CoS_2$ nanocomposites were prepared with nanosized $CoS_2$ particles and [$C_{60}$]fullerene as heated by $700^{\circ}C$ for 2 h in an electric furnace. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) identified the heated $[C_{60}]fullerene-CoS_2$ nanocomposites. Heated $[C_{60}]fullerene-CoS_2$ nanocomposites were investigated the activity of photocatalytic degradation as a catalyst in various organic dyes like acid yellow 23, methylene blue, methyl orange, and rhodamine B with ultraviolet light at 254 nm by UV-vis spectrophotometer.

내염성 효모의 분리 및 세포외 protease의 생산

  • 정승찬;현광욱;김재호;이종수
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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    • pp.559-562
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    • 2000
  • 내염성이며 세포외 protease를 강력하게 생산하는 효모를 재래식 메주효모들과 자연계에서 분리된 내염성 효모들 가운데서 선별하여 Hansenula sp. S-9으로 동정하였다. S-9균주는 $30^{\circ}C$, pH 7.5, 0.5M NaCl을 함유한 배지에서 잘 생육하였고 1.0% beef extract와 1% glucose 및 0.5M NaCl를 함유한 BD배지에서 $30^{\circ}C$로 72시간 배양하였을 때 가장 많은 효소가 생산되었다.

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파로호의 어류상 및 어류군집 (Ichthyofauna and Fish Community in Lake Paro)

  • 최재석;장영수;이광열;김진국;권오길
    • 환경생물
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    • 제22권1호
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    • pp.111-119
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    • 2004
  • 2002년 12월부터 2003년 9월까지 파로호의 어류상 및 어류군집을 조사한 결과는 다음과 같다. 조사된 어류는 총 12과 45종이었다. 한국고유종은 H. mylodon, A. yanatsutae, C. herzi 등 15종 (33.33%)이었다. 우점종은 Z. platypus (72.41%), 아우점종은 H. labeo (9.75%)였고 우세종은 O. uncirostris amurensis (5.98%), Z. temmincki (2.42%), R. brunneus (2.01%), H. olidus (0.88%) 등이었다. 채집된 어종들의 생체량은 Z. platypus 82,863.15g, H. labeo 32,942.63 g, O. uncirostris amurensis 27,482.39 g, C. carpio 6,502.87 g, A. japonica 3,022.15 g,S. scherzeri 2,711.05g의 순으로 나타났다. 파로호에서 확인된 도입종은 A.japonica, H. eigenmanni, H. olidus, O. masou masou, C. urotaenius, R. giurinus, C. carpio (Israeli type), C. cuvieri, M. salmoides, L. macrochirus의 10종이었다. 이 중 C. carpio (Israeli type), C. cuvieri, M. salmoides, L. macrochirus는 국외종이며 A. japonica, H. eigenmanni, H. olidus, O. masou masou, C. urotaenius, R. giurinus는 국내 다른 하천으로부터 도입된 종이다.

Analysis of a Sphingosine 1-phosphate Receptor $hS1P_3$ in Rat Hepatoma Cells

  • Im, Dong-Soon
    • The Korean Journal of Physiology and Pharmacology
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    • 제6권3호
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    • pp.139-142
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    • 2002
  • To examine intracellular signaling of human $S1P_3\;(hS1P_3),$ a sphingosine 1-phosphate (S1P) receptor in plasma membrane, $hS1P_3$ DNA was transfected into RH7777 rat hepatoma cell line, and the inhibition of forskolin-induced cAMP accumulation and activation of MAP kinases by S1P were tested. In $hS1P_3$ transformants, S1P inhibited forskolin-induced activation of adenylyl cyclase activity by about 80% and activated MAP kinases in dose-dependent and pertussis-toxin (PTX) sensitive manners. In oocytes expressing $hS1P_3$ receptor, S1P evoked $Cl^-$ conductance. These data suggested that PTX-sensitive G proteins are involved in $hS1P_3-mediated$ signaling, especially the positive action of S1P in cell proliferation. The potential advantages of rat hepatoma cells for the research of sphingosine 1-phosphate receptor are discussed.

INTEGRAL REPRESENTATIONS FOR SRIVASTAVA'S HYPERGEOMETRIC FUNCTION HA

  • Choi, June-Sang;Hasanov, Anvar;Turaev, Mamasali
    • 호남수학학술지
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    • 제34권1호
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    • pp.113-124
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    • 2012
  • While investigating the Lauricella's list of 14 complete second-order hypergeometric series in three variables, Srivastava noticed the existence of three additional complete triple hypergeometric series of the second order, which were denoted by $H_A$, $H_B$ and $H_C$. Each of these three triple hypergeometric functions $H_A$, $H_B$ and $H_C$ has been investigated extensively in many different ways including, for example, in the problem of finding their integral representations of one kind or the other. Here, in this paper, we aim at presenting further integral representations for the Srivatava's triple hypergeometric function $H_A$.