• 제목/요약/키워드: Quadrupole

검색결과 380건 처리시간 0.027초

금속 산화물 박막제작을 위한 오존 농도 분석 (Analysis of $O_3$ Concentration for Metal Oxide Thin Films Growth)

  • 임중관;박용필;장경욱;이희갑
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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    • pp.331-332
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    • 2005
  • Ozone is ambient gas which is useful for the fabrication of metal oxide thin films under conditions of molecular beam epitaxy. Ozone is condensed by the adsorption method and its concentration is analyzed using the thermal decomposition method. The concentration of ozone exceeds 90 mol% and ozone is supplied for a sufficiently long time to grow oxide thin films. The ozone concentration is also evaluated using a quadrupole mass analyzer and the accuracy of this method is compared with the results of the thermal decomposition method.

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How Shock Wave Interacts with a Vortex ?

  • Chang Keun-Shik;Chang Se-Myong
    • 한국가시화정보학회:학술대회논문집
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    • 한국가시화정보학회 2004년도 춘계학술대회 논문집
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    • pp.1-7
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    • 2004
  • When a vortex diffracts upon encountering a vortex, many strong and weak waves are produced in the course of interaction. They are the cause of shock wave attenuation and noise production. This phenomenon is fundamental to understanding the more complex supersonic turbulent Jet noise. In this paper we have reviewed the research on shock-vortex interaction we have carried on last seven years. We have computationally investigated the parameter effect. When a shock is strong, shock diffraction pattern becomes complex since the slip lines from the triple points on Mach stem curl into the vortex, causing an entropy layer. When the vortex is unstable, vortexlets are brought about each of which make shock diffraction of a reduced intensity. Strong vortex produces quadrupole noise as it impinges into a vortex. Elementary interaction models such as shock splitting, shock reflection, and shock penetration are presented based on shock tube experiment. These models are also verified by computational approach. They easily explain production and propagation of the aforementioned quadrupole noise, Diverging acoustics are explained in terms of shock-vortexlet interactions for which a computational model Is constructed.

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Investigation of the Binding Affinity between Styrylquinoline Inhibitors and HIV Integrase Using Calculated Nuclear Quadrupole Coupling Constant (NQCC) Parameters (A Theoretical ab initio Study)

  • Rafiee, Marjan A.;Partoee, Tayyebe
    • Bulletin of the Korean Chemical Society
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    • 제32권1호
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    • pp.208-212
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    • 2011
  • In this work, the calculated nuclear quadrupole coupling constants of $^{17}O$ in some styrylquinoline conformers were presented. The calculations were carried out to find the relationships between the charge distribution of styrylquinolines and their pharmaceutical behavior and to explore the differences among the electronic structures of some conformers of these potent HIV IN inhibitors. Furthermore, the HIV IN inhibitory of R1 and R2 rotamers was compared. On the basis of our results: - Charge density on oxygen atoms of carboxyl moiety has a dominant role in the drug activity. - The a conformer in which a divalent hydrogen atom is a link, has more capability in antiviral drug treatment. - The R1 conformer, as a $Mg^{+2}$ chelating agent, is better than R2 conformer and thus it is more inhibitor of HIV IN.

Quadrupole 구조를 가진 Tonpilz형 수중 음향 벡터 센서를 이용한 입사각 추정 (Incidence Angle Estimation by the Tonpilz Type Underwater Acoustic Vector Sensor with a Quadrupole Structure)

  • 임영섭;노용래
    • 한국음향학회지
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    • 제31권8호
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    • pp.569-579
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    • 2012
  • 압전 세라믹을 이용한 전형적인 Tonpilz형 수중 음향센서는 외부에서 들어오는 음향 신호를 이에 상응하는 전압으로 변환해 스칼라 양인 음압의 크기만 측정할 뿐 외부에서 들어오는 신호의 방향은 파악할 수 없는 한계가 있다. 이와 같은 문제점을 해결하고자 본 논문에서는 Tonpilz형 트랜스듀서를 이용해 단일 센서만으로도 음압의 크기와 방위각 방향을 동시에 분석해 낼 수 있는 새로운 벡터 센서 구조를 제안하고, 제안된 구조의 타당성을 수식 및 유한요소해석을 통해 검증하였다.

ECR을 이용한 ${SF_6}/{O_2}$ 가스 플라즈마에 의한 ITO의 식각 특성연구 (Etch characteristics of ITO(Indium Tin Oxide)using ${SF_6}/{O_2}$-gas ECR(Electron Cyclotron Resonance) plasmas)

  • 권광호;강승열;김곤호;염근영
    • 한국전기전자재료학회논문지
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    • 제13권7호
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    • pp.563-567
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    • 2000
  • We presented the etch results of indium-tin oxide thin films by using SF$_{6}$/O$_2$gas electron cyclotron resonance plasma and conducted X-ray phtoelectron spectroscopy and quadrupole mass spectrometer analyses for the etch characteristics. The etch rate of the films was greatly dependent on that of oxygen which was the major constituent element of the films. The oxygen was removed by the forms like $O_2$or SOF$_2$. We examined the ratio of atomic content of O and In and the change of this ratio was related to the removal rate of InF$_{x}$ and the S-metal bonding.ing.

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Electric Field Gradients at Copper Sites in the High $T_c$ Superconductor $YBa_2Cu_3O_{7-x}$

  • So Hyunsoo
    • Bulletin of the Korean Chemical Society
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    • 제10권6호
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    • pp.551-554
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    • 1989
  • Quadrupole coupling constants of $^{63}$CU in the high $T_c$ superconductor $YBa_2Cu_3O_7_{-x}$, as determined by NQR or NMR studies, are compared with the values for representative Cu(Ⅱ) complexes determined by analyzing the forbidden lines in their EPR spectra. It is shown that the two NQR lines at 22 and 31 MHz correpsond to the quadrupole coupling constants of a square planar Cu(Ⅱ) complex and a square pyramidal Cu(Ⅱ) complex, respectively.t This result is in agreement with the assignment of these lines to Cu(1) and Cu(2) sites in YBCO based on the NMR spectra of oriented single crystals.

Study of Magnetohydrodynamic Turbulence Using Multi-frequency Synchrotron Polarization Observations

  • Lee, Hyeseung;Cho, Jungyeon;Lazarian, Alex
    • 천문학회보
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    • 제44권1호
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    • pp.44.2-44.2
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    • 2019
  • Turbulent motions perturb magnetic field lines and produce magnetic fluctuations. The perturbations leave imprints of turbulence statistics on magnetic field. Observation of synchrotron radiation is one of the easiest ways to study turbulent magnetic field. First, we obtained the spatial spectrum of synchrotron polarization so that shows how the spectrum is affected by Faraday rotation and how to recover the statistics of underlying turbulence magnetic field. Since polarized synchrotron intensity arising from magnetized turbulence are anisotropic along the direction of mean magnetic field. Secondly, we studied quadrupole ratio to quantitatively describe the degree of anisotropy introduced by magnetic field at multi-wavelengths. This work demonstrated that the spectrum and quadrupole ratio of synchrotron polarization can be very informative tools to get detailed information about the statistical properties of MHD turbulence from radio observations of diffuse synchrotron polarization.

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Neuro-fuzzy modeling of deformation parameters for fusion-barriers

  • Akkoyun, Serkan;Torun, Yunis
    • Nuclear Engineering and Technology
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    • 제53권5호
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    • pp.1612-1618
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    • 2021
  • The fusion-barrier distribution is very sensitive to the structure of the colliding nuclei such as nuclear quadrupole and hexadecapole deformation parameters and their signs. If the nuclei that enter the fusion reaction are deformed, the barrier problem becomes complicated. Therefore the deformation parameters are taken into account in the calculations. In this study, Neuro-Fuzzy approach, ANFIS, method has been used for the estimation of ground-state quadrupole (𝜀2) and hexadecapole (𝜀4) deformation parameters for the nuclei. According to the results, the method is suitable for this task and one can confidently use it to obtain the data that is not available in the literature.

FORMULATION OF NEAR AND FAR ACOUSTIC FIELD FROM AN INCOMPRESSIBLE FLOW FLRCTUATION AROUND THE RIGID WALL

  • Ryu, Ki-Wahn;Lee, Duck-Joo
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 1996년도 제11회 수중음향학 학술발표회 논문집 11th Underwater Acoustics Symposium Proceedings
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    • pp.59-62
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    • 1996
  • A numerical study of a two-dimensional acoustic field is carride ort for a spinning vortex pair located neat a wall to investigate the effect of the wall from the spinning quadrupole source in unsteady vortical flows. Based on the known incompressible flow field, the perturbed compressible acoustic terms derived from the Euler equations are calculated. Non-reflecting boundary conditions on the free field and the solid boundary conditions are developed for a generalized curvilinear coordinates system to investigate the effect of a curced wall. It is concluded that the sound generated by the quadrupole sources of unsteady vortical flows in the presence of a flat wall or a circular cylinder can be calculated by using the source terms of hydrodynamic flow fluctuations in both near and far acoustic fields simultaneously.

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