• Journal of Astronomy and Space Sciences
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• v.19 no.4
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• pp.255-262
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• 2002

We present the infrared spectra of Herbig Ae/Be stars including the Infrared Space Ob-servatory (ISO) data. To investigate the overall properties of their circumstellar dust envelope and/or disk, we combine the IR spectra with photometric data ranging from the UV through the optical into the sub-mm region. We study the general characteristics of the spectral energy distributions using simple analysis. We plot the positions on the HR-diagram to compare with the theoretical pre-main-sequence evolution tracks.

• Journal of Photoscience
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• v.9 no.3
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• pp.51-55
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• 2002

The 77 K emission and excitation spectra, and 298 K infrared and absorption spectra of [Cr(progly)(2,2-tri)]CIO$_4$[progly=prolylglycinate,2,2-tri=N-(2-aminoethyl)-1,2-ethanediamine] have been measured. The vibrational intervals of the electronic ground state are extracted from emission and infrared spectra. The twelve electronic bands due to spin-allowed and spin-forbidden transitions were assigned. Using the observed electronic transitions, a ligand field analysis was performed to determine the metaligand bonding properties for the coordinated atoms. It is found that the carboxylate oxygen of the progly is a strong $\sigma$-and $\pi$-donor while the peptide nitrogen has weak $\pi$-donor property toward chromium(III) ion.

• Bulletin of the Korean Chemical Society
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• v.20 no.1
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• pp.81-84
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• 1999

The emission and excitation spectra of [Cr(NH3)5(imH)](ClO4)3·H2O (imH=imidazole) taken at 77 K are reported. The 298 K visible and far-infrared spectra are also measured. The vibrational intervals of the electronic ground state are extracted from the far-infrared and emission spectra. The ten electronic bands due to spin-allowed and spin-forbidden transitions are assigned. Using the observed transitions, a ligand field analysis has been performed to determine the bonding properties of coordinated imidazole in the title chromium(Ⅲ) complex. It is confirmed that nitrogen atom of the imidazole ligand has a medium it-acceptor property toward chromium(Ⅲ) ion. The zero-phonon line in the excitation spectrum splits into two components by 181 cm-1, and the large 2Eg splitting can be reproduced by the ligand field theory.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1630-1630
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• 2001

NIR specroscopy is widely used today as a quantitative technique for predicting the chemical composition of various agricultural product. However there exist few application for seed quality assessment, especially for seed germinability. This study is to show the possibilities of a nondestructive estimation of germinability in radish (Raphanus sativus L) seeds. The experiment carried out on one radish cultivar (Chung Su Gung Jung, Nong Woo Bio Co., Ltd.) harvested in 1993. NIR(Foss Co.) spectral measurements were carried out on the seeds surface of flat side. The seeds after spectral measurements were planted on blotter individually and observed germination. The seeds were characterized to nongermination and germination group, which in turn grouped to normal and abnormal germination and then compared with the NIR spectra. The spectra from these seed groups were compared each other, The result suggested that NIR spectra could be applicable to determine radish seeds germinability.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.71.2-71.2
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• 2015

We present the high-resolution near-infrared spectra of standard stars observed with Immersion Grating Infrared Spectrograph (IGRINS). IGRINS covers the full spectral range of H and K bands simultaneously with a high spectral resolution (R=40,000), revealing many previously undetected and/or unknown lines. In this work, we present preliminary results of spectroscopic diagnostics for stellar physical parameters. Our ultimate goal is to provide a library of near-infrared spectra of standard stars, which covers all spectral types and luminosity classes, with a high-resolution and high signal to noise ratio ($SNR{\geq}200$).

• Bulletin of the Korean Chemical Society
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• v.22 no.5
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• pp.488-492
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• 2001

As gas chromatography/infrared spectrometry (GC/IR) becomes routinely avaliable, methods must be developed to deal with the large amount of data produced. We demonstrate computer methods that quickly search through a large data file, locating thos e spectra that display a spectral feature of interest. Based on a modified library search routine, these selective data reduction methods retrieve all or nearly all of the compounds of interest, while rejecting the vast majority of unrelated compounds. To overcome the shifting problem of IR spectra, a search method of moving the average pattern was designed. In this moving pattern search, the average pattern of a particular functional group was not held stationary, but was allowed to be moved a little bit right and left.

• Bulletin of the Korean Chemical Society
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• v.13 no.5
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• pp.520-526
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• 1992

The intramolecular fundamental vibrations of $CH_3CN$ trapped in solid argon matrix have been reinvestigated by means of FT-IR spectroscopy in the spectral range of 4000-500 $cm^{-1}$. By employing a quantum detector, infrared spectra could be obtained at matrix to solute ratio of 10000, allowing the clarification of the peaks due to monomeric species more clearly. Temperature controlled diffusion was initiated to identify the dimeric and polymeric species in terms of difference spectra. The assignments of monomeric and dimeric species are found, in general, to agree with the earlier work performed at higher concentration (Ar/$CH_3CN$ = 1500) using a dispersive spectrometer. Nonetheless the difficulty of minute differences between the earlier infrared and Raman spectroscopic results could be resolved. Moreover, the previously unnotified peaks due to polymeric species have been identified.

• Journal of Astronomy and Space Sciences
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• v.14 no.2
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• pp.202-206
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• 1997

We have modeled the infrared spectral energy distributions of proto stars with close attention to the dust envelopes around the stars. The observed spectral energy distributions are closely compared with our models. The model results and observations are compared on IRAS color-color diagrams. Typical model results can explain the observations fairly well.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.4
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• pp.259-271
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• 2023

Since the short-wave infrared spectrum has a significant range of variation depending on the production environment, countries with advanced resource exploration are collecting the spectrum and building a database. Representative organizations include the USGS and CSIRO, and they are currently carrying out a project in China that can synthesize and use a large number of existing data. The USGS library provides a total of 2,457 spectra targeting not only minerals but also various materials that respond to infrared radiation. Among these, there are 1,276 mineral spectra, which are about half of the total. The spectrum title includes information, such as analysis devices (NIC4, BECK, ASDNG, etc.), purity codes (a, b, c, d, u), and measurement methods (AREF, RREF, RTGC, TRAN). Analyzed raw data are provided in ASCII and GIF format. The CSIRO library has a total of 502 spectra, of which the majority, 493, correspond to mineral spectra. The USGS library is a free, publically available resource, while the CSIRO library is bundled with TSG8 or must be purchased separately. Among these, when comparing the eight spectra whose spectral shapes can be analyzed with the spectra of domestic illite, the positions of the absorption peaks are significantly different from those of domestic illite, except for one Japanese illite. Additional research will be needed to determine the causes of such differences, and the domestically relevant databases should be established as well.

• Journal of Astronomy and Space Sciences
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• v.15 no.1
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• pp.151-162
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• 1998

Infrared absorption spectra of 9 bulk samples and 3 acid residues of meteorites were obtained in the mid-infrared region ($4000~400cm^{-1}$). From the know composition of meteorites studied, the possible absorption modes were investigated. Most bands of bulk samples occur in the region below $1200cm^{-1}$ and they are due to metallic oxides and silicates. The spectra of each group can be distinguished by its own characteristic bands. Acid residues show very distinct features from their bulk samples, and absorp-tion bands due to organic compounds are not evident in their spectra. Quantiative analyses for two carbonaceous (Allende CV3 and Murchison CM2) and one ordinary (Carraweena L3.9) chondrites were performed for the presence of fullerene ($C_{60}$) in the meteorites. We calculated the concentration of $C_{60}$ in the acid residues by curve-fitting the spectra with Gaussian functions. The upper limit of $C_{60}$ concentration in these meteorites appears to be less than an order of a few hundred ppm.