• Journal of Photoscience
• /
• 제6권3호
• /
• pp.141-144
• /
• 1999

A Spectroscopic study on a pulme produced by a reactive laser pulse irradiates the graphite target in a nitrogen atmosphere, two emission bands of C2(d3IIg longrightarrowa3 IIu, Swan band) and CN(B2$\Sigma$+ longrightarrowX$^2$$\Sigma$+, Violet band ) were observed. By simulation of the optical emissionspectra, spectroscopic temperature of $C_2$ and CN molecules were obtained. The depended of vibrational and rotational temperatures on the laser fluence and distance from the target as well as the pressure dependence of the emission intensities of $C_2$ and CN was examined to elucidate the expansion dynamics of the plume and formation mechanisms of $C_2$and CN molecules.

• Current Optics and Photonics
• /
• 제4권4호
• /
• pp.345-352
• /
• 2020

We describe a calibration method to improve the accuracy of interferometric snapshot spectroscopic ellipsometry employing a dual-spectrometer sensor scheme. Conventional spectral wavelength calibration of a spectrometer has been performed by using a calibration lamp having multiple peaks at specific wavelength. This paper shows that such a conventional spectrometer calibration method is inappropriate for the proposed interferometric snapshot spectroscopic ellipsometry to obtain highly accurate ellipsometric phase information. And also, systematic error analysis of interferometric snapshot spectroscopic ellipsometry is conducted experimentally.

• Current Optics and Photonics
• /
• 제4권4호
• /
• pp.353-360
• /
• 2020

Adopting an elaborately designed reflective objective consisting of four mirrors, we have developed a rotating-polarizer-type microspot spectroscopic ellipsometer (SE) with an ultra-small spot size. The diameter of the focused beam, whether evaluated using a direct-image method or a knife-edge method, is less than 8.4 ㎛. After proper correction for the polarizing effect of the mirrors in the reflective objective, we unambiguously determine the dispersion of the complex refractive index and the thickness of monolayer MoS₂ using the measured microspot-spectroellipsometric data. The measured ellipsometric spectra are sensitive enough to identify small variations in thickness of MoS₂ flakes, which ranged from 0.48 nm to 0.67 nm.

• 천문학회보
• /
• 제43권2호
• /
• pp.51.1-51.1
• /
• 2018

Based on the DOAO/eShels observations, we have derived radial velocity curves of the three Algol-type spectroscopic binary systems : Algol, ${\beta}$ Aur, and ${\varepsilon}$ Per. The radial velocity amplitudes of the primary and the secondary (K1 and K2) were consistent within a few % of the values from the previous studies. Mass ratios between the two stars that constitutes each system ranges ~1 to ~10. In addition to the orbital elements derived, we discuss about the spectroscopic ability of the DOAO/eShels instrument.

• Current Optics and Photonics
• /
• 제7권4호
• /
• pp.428-434
• /
• 2023

The compensators used in spectroscopic ellipsometers are usually assumed to be ideal linear waveplates. In reality, however, they are elliptical waveplates, because they are usually made by bonding two or more linear waveplates of different materials with slight misalignment. This induces systematic error when they are modeled as linear waveplates. We propose an improved calibration method based on an optical model that regards an elliptical waveplate as a combination of a circular waveplate (rotator) and a linear waveplate. The method allows elimination of the systematic error, and the residual error of optic axis measurement is reduced to 0.025 degrees in the spectral range of 450-800 nm.

• 천문학회보
• /
• 제46권1호
• /
• pp.27.1-27.1
• /
• 2021

I will describe the current progress within the Fifth Generation of SDSS. SDSS-V is an unprecedented all-sky spectroscopic survey of over six million objects. It is designed to decode the history of the Milky Way galaxy, trace the emergence of the chemical elements, reveal the inner workings of stars, and investigate the origin of planets. It will provide the most comprehensive all-sky spectroscopy to multiply the science from the Gaia, TESS and eROSITA missions. SDSS will also create a contiguous spectroscopic map of the interstellar gas in the Milky Way and nearby galaxies that is 1,000 times larger than the state of the art, uncovering the self-regulation mechanisms of galactic ecosystems. It will pioneer systematic, spectroscopic monitoring across the whole sky, revealing changes on timescales from 20 minutes to 20 years. I will highlight key areas of current scientific and technical development as well as opportunities to participate in the survey underway.

• 천문학논총
• /
• 제12권1호
• /
• pp.197-212
• /
• 1997

The general photometric, spectroscopic, and kinematic properties of the late type halo stars are investigated from a sample of known true halo stars. Halo stars are distributed in a lower left region of infrared (J-H) vs (H-K) color-color diagram, which is recomfirmed to be useful for selection of halo stars. They move with average velocity components of 9 km/sec, -14 km/sec, and 5 km/sec in U, V, and W directions respectively. They are distributed seperately from disk stars in a diagram of metallicity index, CaH1/TiO5 vs (R-I).

• BMB Reports
• /
• 제29권3호
• /
• pp.215-220
• /
• 1996

A general procedure to quantitate the reaction of carbodiimides with carboxy groups of proteins is described. Pyridoxamine reacts with the o-acylisourea intermediate generated during the reaction of carboxyl residues with carbodiimides. The extent of the reaction is determined by measuring the spectroscopic properties, absorption and emission, of pyridoxyl residues covalently attached to the proteins. Resolved pig brain aspartate aminotransferase (apoenzyme), inactivated by 1-ethyl-3-(3-dimethylamino propyl) carbodiimide, reacts with $[^{3}H]pyridoxamine$. After trypsin digestion, one peptide labeled with radioactive pyridoxyl was separated by reverse phase HPLC.

• 분석과학
• /
• 제6권3호
• /
• pp.345-348
• /
• 1993

A monchromator controller has been built to drive directly by a personal computer. This controller gives better conveniency and accuracy on spectroscopic experiment when a monochromator has deficient driver. This controller consists with simple electronic circuit and control program. The original spectroscopic precision is retained by using stepper motor. The rate changing method is adopted for short slew time. And the scanning is synchronized with spectrum recording device. Because the controller includes electronic counting ciruit, other program can be executed on personal computer during monochromator scanning.

• Natural Product Sciences
• /
• 제17권4호
• /
• pp.350-353
• /
• 2011

A new daucosteryl derivative, verticilloside (1), was isolated from the seeds of Malva verticillata L. (Malvaceae). The structure was determined to be 3-O-[${\beta}$-D-(6'-linoleoyl)glucopyranosyl]-${\beta}$-sitosterol based on spectroscopic analyses ($^1H$ and $^{13}C$-NMR, DEPT, COSY, HMQC, and HMBC) and chemical reactions.