• 제목/요약/키워드: Monoclinic

검색결과 541건 처리시간 0.028초

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

  • 김남오;김형곤;장성남;이광석;방태환;현승철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 전문대학교육위원
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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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Hexamethylenediaminc digydroiodid의 結晶構造 (The Crystal Structure of Hexamethylenediamine dihydroiodide)

  • 한관섭
    • 대한화학회지
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    • 제7권1호
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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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    • 제14권1호
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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.
    • 통합자연과학논문집
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    • 제9권4호
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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
    • 한국진공학회지
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    • 제12권S1호
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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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    • 제23권6호
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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.

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

  • 정운조;조재철;박계춘;정해덕
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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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[${\AA}$].

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

  • 박계춘;정운조;유용택
    • E2M - 전기 전자와 첨단 소재
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    • 제7권1호
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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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가스 분무법으로 제조한 Ti-Ni-XCu 형상기억합금분말의 특성 (Characteristics of Ti-Ni-(XCu) Shape Memory Alloy Powders made by Gas Atomization Process)

  • 징동훈
    • 한국분말재료학회지
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    • 제6권2호
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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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Al-Fe-Mo 합금에서 준결정상의 생성 및 열분해에 관한 연구 (Formation and Thermal Decomposition of a Quasicrystalline Phase in Al-Fe-Mo Alloys)

  • 김석환
    • 열처리공학회지
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    • 제18권6호
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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.