• 제목/요약/키워드: $MoO_x$

검색결과 412건 처리시간 0.026초

Identification of Actinomycins by High Performance Liquid Chromatography and Fast Atom Bombardment Mass Spectrometry

  • Cho, Seong-Eun;Goo, Yang-Mo;Kim, Kyoung-Ja
    • Archives of Pharmacal Research
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    • 제17권6호
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    • pp.424-427
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    • 1994
  • An acinomycin complex isolated from culture broth of a soil microorganism, SNUS 9305-011 has been examined by High performance liquid chromatography (HPLC). From the analysis of the fractions obtained by column chromatography of the ethyl acetate extract, three actinomycin components are confimed . The HPLC analysis is carried out with a CN-bonded nucleosil column. Comparison of the retention times of the components with those of actinomycin D, C complex, $X_{o{\beta}$, and V and suggests that they are different actinomycins. FBA mass spectra fo the coponents also shows different molecular ions from those of standards and other reported actionbmycins. The present work has demonstrated that actinomycin components can be separated by a CN-bonded HPLC column, and that ocmparison of their HPLC chormatograms with authentic smaples and information on their molecular ions can be successfully employed for indentification of actionmycins.

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방사선 검출기용 다이아몬드 막의 합성 (Synthesis of Diamond films for Radiation Detector)

  • 박상현;김정달;박재윤;김경환;구효근;이덕출
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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    • pp.366-369
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    • 1999
  • Synthetic diamond films have been deposited on the silicon(100) surface and molybdenum substrates using an microwave plasma enhanced vapor deposition (MWPECVD) method. The effect of deposition time, surface morphology, X-ray diffraction pattrm, infrared transmittance and Raman Scattering have been studied, The diamond film deposited on Mo substrate for (100) hours at 40 torr H$_2$-CH$_4$O$_2$ gas system have been shown 1${\mu}{\textrm}{m}$/h of growth rate and good crystallization

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직접구동형 가진기의 개발 및 성능평가 (Development of a Direct Drive Type Exciter and Performance Evaluation)

  • 김오복;박정모;김석현
    • 산업기술연구
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    • 제18권
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    • pp.329-334
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    • 1998
  • The purpose of this study is to design and manufacture a vibration exciter, which can be used in the education and research for the vibration engineering. For this purpose, a direct drive type vibration exciter is developed, which consists of a motor, an inverter, eccentric rotating sleeves and two excitation plates. Developed exciter is tested on some dynamic characteristics to evaluate its excitation performance. Test results show that the developed machine can excite bodies on the horisontal vibrating plates in x,y direction by the constant displacement amplitude in the frequency range below 50Hz, which confirm that the exciter can be used as a vibration testing machine in the low frequency range.

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The Crystal Structure of Metoclopramide

  • Shin, Whan-chul;Chang, Tai-Sik;Koo, Chung-Hoe
    • Bulletin of the Korean Chemical Society
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    • 제4권3호
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    • pp.123-127
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    • 1983
  • The crystal structure of metoclopramide, $C_14H_22ClN_3O_2$, has been determined by X-ray diffraction techniques using diffractometer data obtained by the ${\omega}-2{\theta}$ scan technique with Mo $K\alpha$ radiation from a crystal with space group symmetry $P{\overline{1}}$ and unit cell parameters a = 7.500(1), b = 8.707(2), c = 13.292(2) ${\AA}$; ${\alpha}$ = 101.70(2), ${\beta}$ = 81.20(2), and ${\gamma}$ = $114.90(l)^{\circ}$. The sructure was solved by direct methods and refined by full-matrix least-squares to a final R = 0.055 for the 1524 observed reflections. The bent overall-conformation of the molecule seems to be determined mainly by the bifurcated intramolecular hydrogen bond from the amide nitrogen atom to the methoxy oxygen and the amine nitrogen atoms. The crystal packing consists of the hydrogen bonds, ${\pi}-{\pi}$ interaction and hydrophobic interaction.

육방정계 텅스텐옥사이드 나노분말의 합성과 고성능 가스센서응용을 위한 성능 평가 (Fabrication and Characterization of Hexagonal Tungsten Oxide Nanopowders for High Performance Gas Sensing Application)

  • 박진수
    • 한국분말재료학회지
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    • 제26권1호
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    • pp.28-33
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    • 2019
  • The gas sensor is essential to monitoring dangerous gases in our environment. Metal oxide (MO) gas sensors are primarily utilized for flammable, toxic and organic gases and $O_3$ because of their high sensitivity, high response and high stability. Tungsten oxides ($WO_3$) have versatile applications, particularly for gas sensor applications because of the wide bandgap and stability of $WO_3$. Nanosize $WO_3$ are synthesized using the hydrothermal method. As-prepared $WO_3$ nanopowders are in the form of nanorods and nanorulers. The crystal structure is hexagonal tungsten bronze ($MxWO_3$, x =< 0.33), characterized as a tunnel structure that accommodates alkali ions and the phase stabilizer. A gas detection test reveals that $WO_3$ can detect acetone, butanol, ethanol, and gasoline. This is the first study to report this capability of $WO_3$.

퇴적 온도와 열처리에 따른 SiC에 퇴적된 Ga 도핑된 ZnO의 구조 및 전기적 특성 (Deposition Temperature and Annealing Temperature Dependent Structural and Electrical Properties of Ga-doped ZnO on SiC)

  • 이정호;구상모
    • 한국전기전자재료학회논문지
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    • 제25권2호
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    • pp.121-124
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    • 2012
  • The characteristics of Ga-doped zinc oxide (GZO) thin films deposited at different deposition temperatures (TS~250 to $550^{\circ}C$) on 4H-SiC have been investigated. Structural and electrical properties of GZO thin film on n-type 4H-SiC(0001) were investigated by using x-ray diffraction(XRD), atomic force microscopy(AFM), Hall effect measurement, barrier height from I-V curve and Auger electron spectroscopy(AES). XRD $2\theta$ scan shows GZO thin film has preferential orientation with c-axis perpendicular to SiC substrate surface. The lowest resistivity ($\sim1.9{\times}10^{-4}{\Omega}cm$) was observed for the GZO thin film deposited at $400^{\circ}C$. As deposition temperature increases, barrier height between GZO and SiC was increased. Whereas, resistivity of GZO thin films as well as barrier height between GZO and SiC were increased after annealing process in air atmosphere. It has been found that the c-axis oriented crystalline quality as well as the relative amount of activated Ga3+ ions and oxygen vacancy may affect the electrical properties of GZO films on SiC.

4-크로로-4'-메톡시-2-니트로디페닐아민의 X-선 결정 및 분자구조 결정 (The Crystal and Molecular Structure of the 4-Chloro-4'-Methoxy-2-NitroDi phenylamino $(C_{13}H_{11}N_2O_3CL)$)

  • 남궁해;유재혁;이현미
    • 한국결정학회지
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    • 제2권2호
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    • pp.28-31
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    • 1991
  • 4-크로로-4'-메톡시-2-니트로디페닐아민, (C12H11N2O3CL, FW=278.70)의 단것세포 상수는 a=8,169(3), b=8.883(1), c=9.150(1) h, α =82. 98(1), β=104.80(2), y=101.43(2)", V=627.3 A3, F(000)=288.0, Dc=1.48g/cm3, u=3.06cm-1, 7=295" K, 공간군 Pi, 번호 2, 삼사 정계 이며, Z=2이다. λ (Mo-Ka)=0.7107A을 사용 하여 수집한 독립적인 회절 반점 1541개로 구조분 석한 최종 신뢰도 값은 각각 R=0.032, Rw=0.033 이며, S=0.46이다. 본 화합물은 암모니아의 두개 의 수소 대신에 4-크로로-페닐기와 4-메톡시-페닐기로 치환된 물질로써, 질소와 두 페닐기 사이의 각과 결합거리 들은 각각 125.42", 1.362 및 1.428 A 인바 수소와 함께 SP2_혼성결합을 하고있다. 질소를 포함한 두 면간 각은 63.29"이다. 분자간 어 떠 한 수소결합을 하고 지지 않다.

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전기충격법을 통한 몰리브덴이 도핑된 타이타니아 나노튜브 (The preparation of TiO2 nanotubes with a doping of Mo by potential shock)

  • 하동흔;최진섭
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2017년도 춘계학술대회 논문집
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    • pp.145-145
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    • 2017
  • 음극재에 사용되는 타이타니아 나노튜브($TiO_2$ nanotubes)는 높은 종횡비를 가지고 있으며, 기계적인 강도가 우수하고 화학적인 안정성이 높다. 그러나 낮은 전기전도도와 상대적으로 넓은 밴드갭(bandgap)은 다양한 활용 분야에 이 물질이 활용되는 것을 제한하고 있는 상황이다. 전기 화학적 분야에서 광화학 반응 또는 과전압에서 밴드갭을 줄이기 위한 타이타니아 나노튜브의 나노 구조 변형에 대한 많은 연구가 있어왔다. 본 연구에서는 산화 몰리브덴(Molybdenum oxide)을 촉매로 사용하여 타이타니아 나노튜브에 전기충격법을 이용하여 도핑했다. 생성된 타이타니아 나노튜브를 $450^{\circ}C$에서 1시간 30분 동안 가열하여 타이타니아 나노구조를 아나타제(anatase) 구조로 변형켰다. 타이타니아 나노튜브의 구조적인 변화를 scanning electron microscopy(SEM), energy-dispersive X-ray spectroscopy(EDS) 등을 통해 측정했고 UV-Visiblespectroscopy를 통해 도핑된 타이타니아 나노튜브의 밴드갭을 측정하였다. 몰리브덴이 도핑된 타이타니아 나노튜브는 기존의 타이타니아 나노튜브가 가지는 밴드갭인 3.0 ~ 3.2eV 범위보다 더 낮아진 2.6 ~ 2.8eV의 범위를 가지는 것을 확인하였다. 몰리브덴이 도핑된 타이타니아 나노튜브는 다양한 광촉매 분야에 적용될 수 있을 것으로 예상된다.

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The crystal and molecular structure of chlorpropamide

  • Koo, Chung-Hoe;Cho, Sung-Il;Yeon, Young-Hee
    • Archives of Pharmacal Research
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    • 제3권1호
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    • pp.37-49
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    • 1980
  • Chlorpropamide, $C_{10}H_{13}N_{2}O_{3}SCI$, forms orthofombic crystals of space group $P_{2}_{ 1}2_{1}2_{1}$ with a 9.066 $\pm$ 0.004, b = 5.218 $\pm$ 0.003, c = 26, 604 $\pm$, 0.008 $\AA$, and four molecules per cell. Three dimensional photographic data were collected with Mo-K$\alpha$ radiation. The structure was determined using Patterson, Fourier and Difference syntheses methods and refined by the block-diagonal least-squares methods with anisotropic thermal parameters for all nonhydrogen atoms and isotropic thermal parameters for all hydrogen atomes. The final R value was 0.10 for the 1823 observed independent reflections. The dihedral angle between the planes through the benzene ring and the urea goup is 99$^{\circ}$. The conformational angle formed by the projection of the S-C(1) with that of N(1)-C(7) when the projection is taken along the S-N(1) bond is 76$^{\circ}$. The molecule appears to form with neighbouring molecules two hydrogen bonds, N(1)..H...O(3) and N(2)-H...0(2) of lengths 2.774 and 2.954$\AA$ respectively related by screw diads parallel to the a axis. Adjacent molecules parallel to b and c axis are bound together by van der Wasls forces.

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$BCl_3/N_2$ 유도결합 플라즈마로 식각된 PZT 박막의 식각 특성 (Dry etching properties of PZT thin films in $BCl_3/N_2$ plasma)

  • 구성모;김경태;김창일
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.183-186
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    • 2004
  • The dry etch behavior of PZT thin films was investigated in $BCl_3/N_2$ plasma. The experiments were carried out with measuring etch rates and selectivities of PZT to $SiO_2$ as a function of gas concentration and input rf power, chamber pressure. The maximum etch rate was 126 nm/min when 30% $N_2$ was added to $BCl_3$ chemistry. Also, as input rf power increases, the etch rate of PZT thin films was increased. Langmuir probe measurement showed the noticeable influence of $BCl_3/N_2$ mixing ratio on electron temperature and electron density as input rf power increased. The variation of Cl radical density as plasma parameters changed was examined by Optical Emission Spectroscopy (OES) analysis. According to X-ray diffraction (XRD) analysis, PZT thin films were damaged in plasma and an increase in (100), (200) and (111) phases showed the improvement in structure of the PZT thin films after the $O_2$ annealing process.

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