• 제목/요약/키워드: New spectra

검색결과 762건 처리시간 0.032초

금속 단결 정면에 증착된 층의 두께측정 (Thickness Measurement of Overlayer Deposited on Single Crystal)

  • 민항기;변대현
    • 한국진공학회지
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    • 제1권1호
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    • pp.73-77
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    • 1992
  • 표면 연구에서 단결정면 위에 진공 증착된 층의 두께를 측정하는 일은 쉽지 않다. 지금까지 몇 가지 측정방법들이 알려지고 있으나 이들 방법은 섬세한 고가장비를 필요로 한 다. 본 연구에서는 단순히 Auger 스펙트럼을 이용하여 두께를 측정할 수 있는 간단한 방법 을 제안하고 있다. 또한 구리 단결정면 위에 증착된 철 원자의 두께 측정에 관한 예가 제시 되고 있다.

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Precise measurements of distance using large scale structure formation

  • 송용선;서희종
    • 천문학회보
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    • 제36권2호
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    • pp.51.1-51.1
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    • 2011
  • We introduce new methods to measure distance in precision using large scale structure formation. The accuracy to determine geometrical factors is enhanced in comparison to the previous method known as BAO. We determine both D_A and H simultaneously as well as structure of growth of density fluctuations and peculiar velocities. Our method is independent of any given prior on large scale structure formation such as the shape of spectra.

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원지의 염기성성분에 관한 연구 (Studies on the Alkaloid from Polygala tenuifolia Willdenow)

  • 김제훈
    • 약학회지
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    • 제8권2호
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    • pp.59-61
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    • 1964
  • A new alkaloid, named tenuidine was isolated from Polygala tenuifolia Willdenow. Its molecular formula corresponded to $C_{21}$ $H_{31}$ $O_{5}$ $N_{3}$ and its constants were m.p.256, [.alpha.]$_{D}$$^{18.5}$=1200.deg.(ethanol). Its infrared absorption spectra exhibited bands at 3.300, 1600, 1580, 1500 $cm^{-1}$ / confirming indole ring and at 2800-2700 $cm^{-1}$ / indicating quinoline ring. Bands at 1610, 1530 $cm^{-1}$ / indicated the presences of benzene ring and 1642$cm^{-1}$ / carbochelate.e.e.

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Proposal and Analysis of Wavelength-Switchable Optical Fiber Filter Based on a Solc Type

  • Kim, Min-Wook;Jung, Jae-Hoon
    • Journal of the Optical Society of Korea
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    • 제12권3호
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    • pp.147-151
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    • 2008
  • This paper proposes a new polarization-independent Sagnac birefringence loop structure-based multiwavelength-periodic filter and presents measurements and analysis of its spectrum. The filter can be used in several schemes by adjusting the orientation angles of two quarter waveplates and the operating characteristics in the reflection type are analyzed including dispersion and polarization mode dispersion at each principal axis. This filter has polarization-independent spectra but a polarization-dependent dispersion, consequently polarization mode dispersion whose values changes with operating schemes.

Coherent Combination of Baryon Acoustic Oscillation Statistics and Peculiar Velocity Measurements from Redshift Survey

  • 송용선
    • 천문학회보
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    • 제36권1호
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    • pp.46.1-46.1
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    • 2011
  • New statistical method is proposed to coherently combine Baryon Acoustic Oscillation statistics (BAO) and peculiar velocity measurements exploiting decomposed density--density and velocity--velocity spectra in real space from the observed redshift distortions in redshift space, 1) to achieve stronger dark energy constraints, sigma(w)=0.06 and sigma(w_a)=0.20, which are enhanced from BAO or velocity measurements alone, and 2) to cross--check consistency of dark energy constraints from two different approaches; BAO as geometrical measurements and peculiar velocity as large scale structure formation observables.

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Bicubic Splines in Problems of Modeling of Multidimensional Signals

  • Bahramov, Sayfiddin;Jovliev, Sanjar
    • Journal of information and communication convergence engineering
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    • 제9권4호
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    • pp.420-423
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    • 2011
  • The paper is devoted to problem of spline modeling of multidimensional signals. A new method of nodes location for curves and surfaces computer construction in multidimensional spaces by means of B-splines is presented. The criteria are which links a square-mean error caused by high frequency spline distortions and approximation intervals is determined and necessary theorem is proved. In this method use a theory of entire multidimensional spectra and may be extended for the spaces of three, four and more variables.

Molecular Enginering. Container Hosts Having Eight Undecyl Substituents Have High Solubility in Chlorinated Solvents

  • 백경수;주경미;권석준;임혜재;김용주
    • Bulletin of the Korean Chemical Society
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    • 제18권1호
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    • pp.80-86
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    • 1997
  • Nine new solubility-increased container hosts having eight undecyl substituents were synthesized and characterized. 1H NMR spectral data showed integral inclusion state of carceplexes and their stability. 1H NMR chemical shifts of guest DMA were correlated to the host's cavity dimensions shrinked by constrictive binding. Carceplex and hemicarcerand showed their distinctive FD mass spectra.

Contact-Only and Dipolar-Only Mixtures of Lanthanide NMR Shift Reagents

  • Lee, Man-Ho
    • Bulletin of the Korean Chemical Society
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    • 제7권6호
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    • pp.433-438
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    • 1986
  • Two new types of NMR shift reagents, one giving dipolar-only and the other giving contact-only shifts, can be prepared simply by mixing two appropriate $Ln(fod)_3$(Ln = Pr, Nd, Eu, and Yb) reagents in certain ratios. The $^1H$ and $^{13}C$ NMR spectra of pyridine-type substrates, quinoline and isoquinoline, whose paramagnetic shifts are normally a composite of contact and dipolar contributions with single lanthanide shift reagents, show the feasibility of this approach.

Ozonolyses of Cycloalkenes: Trapping of Carbonyl Oxide by Trifluoroacetophenone

  • 이주연;이치원;허태성
    • Bulletin of the Korean Chemical Society
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    • 제19권11호
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    • pp.1244-1248
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    • 1998
  • Ozonolysis reactions of cyclic olefins 1a-c and norbomene In in the presence of trifluoroactophenone 6 provided the corresponding cross-ozonides 7a-c and 7n. Further reactions of ozonides 7a-c and 7n with the independently prepared carbonyl oxide 11 gave diozonides of structure l0a-c and 10n. The ozonolysis of 1methylcyclopentene 12a and 1-methylcyclohexene 12b in the presence of trifluoroactophenone 6 provided exclusively ozonide 15 and 16 derived from capture of carbonyl oxide 13. All of the new ozonides have been isolated as pure substances and characterized by their 1H NMR and 13C NMR spectra.

SOME FREDHOLM THEORY RESULTS AROUND RELATIVE DEMICOMPACTNESS CONCEPT

  • Chaker, Wajdi;Jeribi, Aref;Krichen, Bilel
    • 대한수학회논문집
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    • 제36권2호
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    • pp.313-325
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    • 2021
  • In this paper, we provide a characterization of upper semi-Fredholm operators via the relative demicompactness concept. The obtained results are used to investigate the stability of various essential spectra of closed linear operators under perturbations belonging to classes involving demicompact, as well as, relative demicompact operators.