• Title/Summary/Keyword: SB-1

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A study on the characteristics and growth $Al_xGa_{1-x}Sb$ ($Al_xGa_{1-x}Sb$의 결정성장과 특성에 관한 연구)

  • 이재구;박민서;정성훈;송복식;문동찬;김선태
    • Electrical & Electronic Materials
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    • v.10 no.3
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    • pp.226-232
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    • 1997
  • Ternary semiconductor $Al_{x}$G $a_{1-x}$ Sb crystals which have energy gap of 0.7eV-1.6 eV at room temperature according to the composition ratios were grown by the vertical Bridgman method. The characteristics of the crystals were investigated by XRD, HRTEM and Hall effect. The lattice constants of $Al_{x}$G $a_{1-x}$ Sb crystals were varied from 6.096A over .deg. to 6.135A over .deg. with the composition ratio x. The Hall effect of the $Al_{x}$G $a_{1-x}$ Sb crystals were measured by van der Pauw method with the magnetic field of 3 kilogauss at room temperature. The resistivities of Te-doped $Al_{x}$G $a_{1-x}$ Sb crystals were increased from 0.071 to 5 .OMEGA.-cm at room temperature according to the increment of the composition ratio x. The mobilies of $Al_{x}$G $a_{1-x}$ Sb crystals varied with the composition ratio x resulted in the following three different regions of GaSb-like (0.leq.x.leq.0.3), intermediate (0.3.leq.x.leq.0.4) and AlSb-like (0.4.leq.x.leq.l).q.l).q.l).q.l).

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Non-specific in vivo inhibition of CK1 by the pyridinyl imidazole p38 inhibitors SB 203580 and SB 202190

  • Shanware, Naval P.;Williams, Leah M.;Bowler, Michael J.;Tibbetts, Randal S.
    • BMB Reports
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    • v.42 no.3
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    • pp.142-147
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    • 2009
  • Small-molecule inhibitors of protein kinases have contributed immensely to our understanding of biological signaling path-ways and have been exploited therapeutically for the treatment of cancers and other disease states. The pyridinyl imidazole compounds SB 203580 and SB 202190 were identified as ATP competitive antagonists of the p38 stress-activated protein kinases and have been widely used to elucidate p38-dependent cellular processes. Here, we identify SB 203580 and SB 202190 as potent inhibitors of stress-induced CREB phosphorylation on Serine 111 (Ser-111) in intact cells. Unexpectedly, we found that the inhibitory activity of SB 203580 and SB 202190 on CREB phosphorylation was independent of p38, but instead correlated with inhibition of casein kinase 1 (CK1) in vitro. The inhibition of CK1-mediated CREB phosphorylation by concentrations of pyridinyl imidazoles commonly employed to suppress p38, suggests that in some cases conclusions of p38-dependence derived solely from the use of these inhibitors may be invalid.

Toxicity Study of a New PEG-hemoglobin SB1, a Red Blood Cell Substitute: Single Intravenous Administration in Beagle dogs (새로운 혈액대용제제 PEG-헤모글로빈 SB1의 개에 대한 단회정맥투여 독성시험)

  • 한정희;차신우;김종춘;기충용;이미가엘;노광
    • Biomolecules & Therapeutics
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    • v.10 no.2
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    • pp.114-116
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    • 2002
  • This study was performed to investigate the acute toxicity of PEG-hemoglobin SB1, a blood substitute, in beagle dogs. The male and female dogs were administered intravenously at the doses of 0.4375, 0.875 and 1.75 g/kg body weight, respectively. After a single intravenous administration of SB1 to dogs, we observed them daily for 2 weeks. SB1 did not induce any toxic signs in the mortalities, clinical signs, body weight changes, and gross necropsy findings of dogs. Based on these results, acute toxicity, dogs SB1 may have no side effect and its $LD_{50}$ value may be over 1.75 g/kg (25 ml/kg) of body weight in dogs.

Crystal Structure of Hexapotassium Undecahydrogen Tetratungsto Hexaantimonate(Ⅴ) Tetrahydrate (Hexapotassium Undecahydrogen Tetratungsto Hexaantimonate(Ⅴ) Tetraphydrate의 결정 구조)

  • Park, Gi Min;Yoshiki Ozawa;Lee, Uk;Lee, Uk
    • Journal of the Korean Chemical Society
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    • v.38 no.5
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    • pp.359-365
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    • 1994
  • The crystal stucture of hexapotassium undecahydrogen tetratungsto hexaantimonate(V) tetrahydrate has been determined from single crystal X-ray diffraction data. Crystal data are as follows: $K_6H_{12}[Sb_6W_4O_{36}]{\cdot}4H_2O$, Fw = 2360.62, tetragonal, I$4_1$/a, a = 10.799(1) ${\AA}$, c = 35.244(5) ${\AA}$, V = 4110.1(7) ${\AA}^3$, Z = 4, $D_x$ = 3.82 g$cm^{-3}$, $\mu(MoK\alpha)$ = 160.15 $cm^{-1}$, T = 293 K, final R = 0.0356 for 2400($F_0 > 3\sigma(F_0))$ independent reflections. The $[H_{12}Sb_6W_4O_{36}]^{-6}$ polyanion independently consists of one tungsten, two antimony, and nine oxygen atoms and belongs to the $\bar4(S_4)$ point group. This polyanion is formed by two open octahedra five membered ring of Sb(3)$O_6-W(1)O_6-Sb(2)O_6-W(1)O_6-Sb(3)O_6$ which is connected at right angle. The Sb-W, Sb-O, and W-O bond distances range from 3.2304(9) to 3.2403(5) $\AA$, 1.745(8) to 2.334(6) $\AA$, and 1.914(7) to 2.039(7) $\AA$, respectively.

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Growth and Magnetic Characteristics of MnSb Epilayer by Hot-Wall Epitaxy (Hot-Wall Epitaxy에 의한 MnSb 박막의 성장과 자기적 특성)

  • Lee, Man-Young
    • Journal of the Korean Graphic Arts Communication Society
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    • v.22 no.2
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    • pp.151-162
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    • 2004
  • MnSb layers were grown on GaAs(100), (111)A and (111)B substrates by hot wall epitaxy under various growth conditions. Growth condition dependence of structural properties of the layers was examined. The growth direction and structural properties of MnSb/GaAs(100) depend on Sb source and substrate temperatures. The smooth MnSb(10.1)/GaAs(100) interface was obtained under the appropriate growth condition. On the other hand, MnSb(00.1) layers were grown on GaAs(111) substrates. The quality of the layers on (111)B was superior to that on GaAs(111)A, but degraded as in increasing Sb source temperature during the growth. The $Mn_2Sb$ domain was generated in the layers grown under conditions of low Sb source temperature and high substrate temperature on GaAs(111) substrates.

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Synthesis of SnSb alloys using high energy ball-miiling and its lithium electrochemical behavior (고에너지 볼밀을 이용한 SnSb 합금 분말 제조와 리튬 전기화학적 특성)

  • Kim, Dae Kyung;Lee, Hyukjae
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.28 no.5
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    • pp.191-198
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    • 2018
  • SnSb alloy powders with excess Sn or Sb are fabricated by the high energy ball-milling of pure Sn and Sb powders with different Sn/Sb molar ratios, and then their material properties and lithium electrochemical performances are investigated. It is revealed by X-ray diffraction that SnSb alloys are successfully synthesized, and the powder size is decreased via ball-milling. Charge-discharge test using a coin-cell shows that the best result, in terms of the cyclability and the capacity after 50 cycles, comes from the electrode composed of Sn : Sb = 4 : 6, i.e. the capacity of $580mAh\;g^{-1}$ after 50 cycles. When the electrode is composed of Sn : Sb = 3 : 7, however, the capacity is noticeably decreased by the restrained Sn reaction with Li-ion. The pure SnSb alloy powders (Sn : Sb = 5 : 5) results in the second best performance. In the case of Sn-rich SnSb alloys, the initial capacity is relatively high, but the capacity is quickly fading after 20 cycles.

General Pharmacology of PEG-Hemoglobin SB1

  • Kim, Eun-Joo;Lee, Rae-Kyong;Bak, Ji-Yeong;Choi, Gyu-Kap
    • Biomolecules & Therapeutics
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    • v.7 no.2
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    • pp.170-177
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    • 1999
  • PEG-hemoglobin SB1 (SB1), which is a hemoglobin-based oxygen carrier, is intended to use as a safe blood substitute against brain ischemia and stroke. The general pharmacological profiles of SB1 were studied. The doses given were 0, 5, 10, 20 ml/kg and drugs were administered intravenously. The animals used for this study were mouse, rat and guinea pig. SB1 showed no effects on general behavior, motor coordination, spontaneous locomotor activity, hexobarbital sleeping time, anticonvulsant activity, analgesic activity, blood pressure and heart rate, left ventricular peak systolic pressure, left ventricular end diastolic pressure, left ventricular developing pressure, double product, heart rate, coronary flow rate, smooth muscle contraction using guinea pig ileum, gastrointestinal transport, gastric secretion, urinary volume and electrolyte excretion at all doses tested except the decrease of body temperature. These findings demonstrated that SB1 possesses no general pharmacological effects at all doses tested.

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Secretion Stimulation of Golden Vernish Sap from Dendropanax morbifera Lev. (황칠(黃漆)나무의 칠액(漆液) 분필(分泌) 촉진(促進))

  • Kim, Sea Hyun;Jung, Nam Chul;Na, Chun Soo;Kim, Sam Sik
    • Journal of Korean Society of Forest Science
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    • v.87 no.2
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    • pp.253-259
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    • 1998
  • The stimulated secretion of golden varnish sap by the infection of microorganisms on the bark of Dendropanax morbifera Lev. was observed in the natural habitats. Four candidate strains of such microorganisms(i.e., Sb1, Sb2, Sb3 and Sb4) were isolated from the bark of D. morbifera which was infected in natural. Of them, Sb3 and Sb4 strains showed stimulated secretion of golden vernish sap with the greatest stimulation by Sb4 strains. The yield of golden varnish sap from the bark of D. morbifera was boosted about 3.4~7.7 times by the inoculation of Sb4 strain in compassion with that collected from lacquer tree(Rhus verniciflua Stokes) by the traditional method. The mycelium color of Sb4 strain was grayish white. The optimum growth temperatures and pH were ranged from 30 to $35^{\circ}C$ and from pH 6.5 to 7.0.

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Joining and properties of electrode for CoSb3 thermoelectric materials prepared by a spark plasma sintering method (방전 플라즈마 소결법을 이용한 CoSb3계 열전재료의 전극 접합 및 특성)

  • Kim, K.H.;Park, J.S.;Ahn, J.P.
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.20 no.1
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    • pp.30-34
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    • 2010
  • $CoSb_3$-based skutterudite compounds are promising candidates as thermoelectric (TE) materials used in intermediate temperature region. In this study, sintering of $CoSb_3$ powder and joining of $CoSb_3$ to copper-molybdenum electrode have been simultaneously performed by spark plasma sintering technique. The Ti foil was used for preventing the diffusion of copper into $CoSb_3$ and the Cu : Mo = 3 : 7 Vol. ratio composition was selected by the consideration of thermal expansion coefficients. The insertion of Ti interlayer between Cu-Mo and $CoSb_3$ was effective to join $CoSb_3$ to Cu-Mo by forming an intermediate layer of $TiSb_2$ at the Ti-$CoSb_3$ boundary. However, the formation of TiSb and TiCoSb intermediate layers deteriorated the joining properties by the generation of cracks in the interface of intermediate layer/$CoSb_3$ and intermediate/intermediate layers.

Ge-Sb-Te 삼성 분계에서의 열처리 온도에 따른 구성 원소의 상호확산 특성

  • Bang, Gi-Su;Lee, Seung-Yun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.218.1-218.1
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    • 2013
  • GeSbTe 삼원계 칼코겐화물 합금은 광디스크 및 상변화 메모리에서 활성물질로 사용되는 대표적인 재료이다. GeSbTe 합금은 결정질 상과 비정질 상의 두 종류의 상을 갖는데 그 상에 따라 반사율 및 전기저항이 서로 다르기 때문에 활성물질로서 작용한다. GeSbTe 합금 구성원소의 일부를 포함하는 두 종류의 물질로 접합을 형성하고 열처리 공정을 수행함으로써 GeSbTe 합금을 국부적으로 생성하는 방법이 최근에 보고되었다. 이러한 방법을 상변화 메모리 소자 제조에 이용하면 GeSbTe 합금을 제한된 영역에 나노 스케일로 만드는 것이 가능해져서 GeSbTe 합금의 상변화를 유도하는데 필요한 프로그래밍 전류를 낮추는 효과를 얻을 수 있다. 상변화 메모리 소자 내에서의 GeSbTe 합금의 두께 또는 크기는 상변화 메모리 소자의 동작 특성을 좌우하는 중요한 파라미터이며 이것은 열처리 공정 조건에 따라 결정되므로 열처리 공정 조건에 따라 GeSbTe 합금이 생성되는 양상이 어떻게 변화하는지를 밝힐 필요가 있다. 따라서 본 연구에서는 다양한 열처리 온도 조건에서 Ge-Sb-Te 삼성 분계에서의 구성 원소들의 상호확산 거동을 조사하였다. 순수한 Ge 박막과 조성이 다른 SbTe 박막의 접합을 형성하고 773K까지의 온도 범위에서 열처리를 실시하였다. Auger 수직 분석을 이용하여 Ge, Sb, 및 Te 원소의 깊이 방향의 확산 정도를 조사하였으며 그 결과로서 열처리 온도가 증가함에 따라 상호확산 정도가 심해지고 Te 원소가 상호확산에 있어서 중요한 역할을 한다는 사실을 확인하였다.

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