• Title/Summary/Keyword: Monoclinic

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The Hall Effect in Binary Compound Silver telluride Single Crystal (2원화화물 $Ag_2Te$ 단결정의 Hall 효과 특성)

  • Kim, N.O.;Kim, H.G.;Jang, S.N.;Lee, K.S.;Bang, T.W.;Hyun, S.C.
    • Proceedings of the KIEE Conference
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    • 2004.07e
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    • pp.134-136
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    • 2004
  • The results of investigations of $Ag_2Te$ crystal is presented. $Ag_2Te$ crystal was grown by the Bridgman method. The $Ag_2Te$ crystal was an monoclinic structure with lattice constance a = 8.1686 A, b = 9.0425 ${{\AA}}$, c = 8.0065 ${{\AA}}$. Hall effect shows a n-type conductivity in the $Ag_2Te$ crystal. The electrical resistivity values was $1.080e^{-3}{\Omega}cm$ and electron mobility was $-5.48{\times}10^3cm^2/V{\cdot}sec$ at room temperature(RT).

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The Crystal Structure of Hexamethylenediamine dihydroiodide (Hexamethylenediaminc digydroiodid의 結晶構造)

  • Kwan-sub Han
    • Journal of the Korean Chemical Society
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    • v.7 no.1
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    • pp.74-84
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    • 1963
  • Hexamethylenediamine dihydroiodide is monoclinic, with cell dimensions $a=4.85{\AA}$, $b=12.77{\AA}$, $c=9.73{\AA}$, ${\beta}=91.5^{\circ}$ The space group is $P2_1/c$, with two molecules per unit cell. It has a center of symetry in the molecule. All atomic positions are determined by means of a two-dimensional patterson synthesis and fourier synthesis. The C-N bond distance is $1.48{\AA}$ and the C-C bond distances are lying between $1.55{\AA}$, and $1.59{\AA}$. The iodine atom is bonded by hydrogen bridges of $3.59{\AA}{\pm}0.1{\AA}$ to nitrogen atoms and surrounded by three nitrogen atoms. The hexamethylenediamine chain is zigzag in the hexamethylenediamine dihydrochloride molecules though, it is not zigzag in the hexamethylenediamine dihydroiodide.

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The Crystal Structure of Licarin-B $(C_{20}H_{20}O_4)$, A Component of the Seeds of Myristica fragrans

  • Kim, Yang-Bae;Park, Il-Yeong;Shin, Kuk-Hyun
    • Archives of Pharmacal Research
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    • v.14 no.1
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    • pp.1-6
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    • 1991
  • The crystal structure of licarin-B, a component of Myristicae Semen was determined by single crystal X-ray diffraction analysis. Crystal of the compound, which was recrystallized from the mixture of hexane and ether, is monoclinic with a=12.740(1), b=7.219(1), c=9.284(1) ${\AA}$, ${\beta}=94.75(1)^{\circ}$, $D_x=1.26$, $D_m=1.27\;g/cm^3$, space group P21, and Z=2. The structure was solved by direct method and refined by least-squares procedure to the final R value of 0.040 for 1532 independent reflections ${F{\ge}3{\sigma}(F)}$. The compound is a dimeric phenylpropanoid, and belongs to the neolignan analogues. The molecules are arranged along with the screw axis. The intermolecular contacts appear to be the normal van der Waals' forces.

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Crystal Structure Analysis of 4-Chloro-2{[(2-hydroxy-5-methylphenyl)amino]methyl}5-methylphenol

  • Sharmila, P.;Rajesh, R.;Venkatesan, R.;Ganapathy, Jagadeesan;Aravindhan, S.
    • Journal of Integrative Natural Science
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    • v.9 no.4
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    • pp.261-267
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    • 2016
  • The crystal structure of the saliciline derivatives 4-chloro-2{[(2-hydroxy-5-methylphenyl)amino]methyl}5-methylphenol ($C_{15}H_{15}ClNO_2$) has been determined from single crystal X-ray diffraction data. In the title compound crystallizes in the monoclinic space group P21/c with unit cell dimension $a=11.5241(2){\AA}$, $b=8.733(2){\AA}$ and $c=13.649(2){\AA}$ [${\alpha}=90^{\circ}$, ${\beta}=130.876(2)^{\circ}$ and ${\gamma}=90^{\circ}$]. the title compound are essentially planar conformation. The compound lies across a crystallographic inversion centre and adopts E configurations with respect to the C-N bonds. The crystal packing of the molecules of compound is stabilized through weak O-H...O inter molecular interactions.

Synthesis of Zirconium Oxides on silicon by Radio-Frequency Magnetron Sputtering Deposition

  • Ma, Chunyu;Zhang, Qingyu
    • Journal of the Korean Vacuum Society
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    • v.12 no.S1
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    • pp.83-87
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    • 2003
  • Zirconium oxide films have been synthesized by radio-frequency magnetron sputtering deposition on n-Si(001) substrate with metal zirconium target at variant $O_2$ partial pressures. The influences of $O_2$ partial pressures of the morphology, deposition rate, microstructure, and the dielectric constant of $ZrO_2$ have been discussed. The results show that deposition rate of $ZrO_2$ films decreases, the roughness, and the thickness of the native $SiO_2$ interlayer increases with the increase of $O_2$ partial pressure. $ZrO_2$ films synthesized at low $O_2$ partial pressure are amorphous and monoclinic polycrystalline in nanometer scale at low $O_2$ partial pressure. The relative dielectrics of $ZrO_2$ films are in the range of 12 to 25.

H2S Gas Sensing Properties of CuO Nanotubes

  • Kang, Wooseung;Park, Sunghoon
    • Applied Science and Convergence Technology
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    • v.23 no.6
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    • pp.392-397
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    • 2014
  • CuO nanotubes are synthesized using $TeO_2$ nanorod templates for application to $H_2S$ gas sensors. $TeO_2$ nanorod templates were synthesized by using the VS method through thermal evaporation. Scanning electron microscopy, transmission electron microscopy and X-ray diffraction showed that the synthesized nanotubes were monoclinic-structured polycrystalline CuO with diameter and wall thickness of approximately 100~300 nm and 5~10 nm, respectively. The CuO nanotube sensor showed responses of 136~325% for the $H_2S$ concentration of 0.1~5 ppm at room temperature. These response values are approximately twice as high as that of the CuO nanowire sensor for the same concentrations of $H_2S$ gas. Along with the investigation of the performance of the sensors, the mechanisms of $H_2S$ gas sensing of the CuO nanotubes are also discussed in this study.

A study on structural characteristics of Se thin film by fabrication temperature (제작 온도에 따른 Se박막의 구조적 특성에 관한 연구)

  • 정운조;조재철;박계춘;정해덕
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.05a
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    • pp.1.1-5
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    • 1996
  • Structural characteristics in Se thin film fabricated by EBE method had been studied. Se thin film was deposited with noncrystalline until substrate temperature of 100$^{\circ}C$. But Se film was grown with monoclinic at substrate temperature of over 150$^{\circ}C$. Lattice constants of it were as follow: a=12.76[${\AA}$], b=9.15[${\AA}$], c=10.4[${\AA}$]. Finally, after heat-treatment at 150$^{\circ}C$ for 15 min with substrate temperature of 100$^{\circ}C$, noncrystalline Se was proved to be hexagonal. Lattice constants of it were as follow: a=4.27[${\AA}$], c=4.83[${\AA}$].

Characteristics of $SnO_2$/a-Se/AI sample ($SnO_2$/a-Se/AI 소자의 특성)

  • 박계춘;정운조;유용택
    • Electrical & Electronic Materials
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    • v.7 no.1
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    • pp.7-14
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    • 1994
  • Structural and optical characteristics in $SnO_2$/a-Se/Al sample by aging variation and applying constant voltage had been investigated. a-Se was varied with monoclinic structure and its surface was greatly exchanged. Its capacitance was first decreased and then increased and its photo-current, photo-voltage and photo-capacitance were increased gradually with day and applying voltage. From the results, crystallization of a-Se and dopant trap level formation had been identified. Also, it was acknowledged $SnO_2$/a-Se/Al sample is useful in photovoltaic and solid thin film cell.

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Characteristics of Ti-Ni-(XCu) Shape Memory Alloy Powders made by Gas Atomization Process (가스 분무법으로 제조한 Ti-Ni-XCu 형상기억합금분말의 특성)

  • 징동훈
    • Journal of Powder Materials
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    • v.6 no.2
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    • pp.171-177
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    • 1999
  • Ti-45.2at.%Ni-5at.%Cu and Ti-40.2at.%Ni-10atat.%Cu alloy powders were fabricated by gas atomization process. The microstructures, Shape, hardness and phase transformation behaviors of the powders were investigated by means of optical microscopy, scanning electron microscopy, micro-hardness measurement, x-ray diffraction analyses and differential scanning calorimetry. The hardness of the Ti-Ni-XCu alloy powders decreased as Cu-content increased. The x-ray diffraction analyses were carried out for powders without heat treatment, and those that treated at 85$0^{\circ}C$ for an hour in a vaccum state($10^5$ torr) and then quenched into ice water. The intensity of B$19^t$ phase increased with heat treating. The monoclinic B$19^t$ martensite was formed in the Ti-Ni-XCu alloy powders during cooling.

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Formation and Thermal Decomposition of a Quasicrystalline Phase in Al-Fe-Mo Alloys (Al-Fe-Mo 합금에서 준결정상의 생성 및 열분해에 관한 연구)

  • Kim, Suk Hwan
    • Journal of the Korean Society for Heat Treatment
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    • v.18 no.6
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    • pp.362-368
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    • 2005
  • Formation and thermal stability of a quasicrystalline phases in Al-Fe-Mo alloys were investigated by means of melt-spinning process and subsequent heat treatment test. Thermal decomposition and phase transformation process of the as-spun alloys were studied using X-ray diffraction and electron microscopy. The melt-spun Al-Fe-Mo alloys contained an icosahedral quasicrystalline phase with a quasilattice constant of 0.457 nm. Icosahedral phase formed at a composition of $Al_{82.5}Fe_{14}Mo_{3.5}$ as a metastable phase during rapid solidification was transformed into the stable crystalline phases, cubic 1/0 approximant and monoclinic ${\lambda}$-phase, upon heating. A metastable icosahedral and cubic(a = 0.93 nm) phases in as-spun $Al_{65}Fe_{20}Mo_{15}$ alloy were decomposed into two cubic(a = 0.62, 0.31 nm) phases by heat treatment.