• NEWSLETTER 전기공업
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• no.99-20 s.237
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• pp.31-36
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• 1999

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3800-3805
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• 2012

Infrared(IR) reflective black cool pigment and paint which is used for interior/exterior materials(IR reflectance >30%) to prevent heat island effect and to increase energy efficiency were studied. Cool pigment was synthesized using mixture of $Fe_2O_3$ and $Cr_2O_3$ with calcination from 900 to $1,200^{\circ}C$. Cool paint was prepared by formulation of cool pigment, acrylic resins, and other additives. Results showed that optimum color fixation of pigment obtained by mole ratio of Fe to Cr was 0.9 with calcination temperature at $1,000^{\circ}C$. The cool paint formulated by 20% pigment and 1.5% dispersive additive with $125{\mu}m$ thickness of coated layer showed optimum IR reflectance. Temperature difference on surface between cool paint and ordinary paint(STD) was $36.5^{\circ}C$ and IR reflectance(TSR) was 39.3% at wavelength from 700 to 2,500nm. And color change was not detected during 500hrs weathering test.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.1
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• pp.52.2-52.2
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• 2011

The correlation between black hole mass and galaxy stellar velocity dispersion gives an important clue on the black hole growth and galaxy evolution. In the case of AGN, however, it is extremely difficult to measure stellar velocity dispersions in the optical spectra since AGN continuum dilutes stellar absorption features. In contrast, stellar velocity dispersions of active galaxies can be measured in the near-IR, where AGN-to-star flux ratio is much smaller, particularly with the laser-guide-star adaptive optics. However, it is crucial to test whether the stellar velocity dispersion measured from the near-IR spectra is consistent with that measured from the optical spectra. Using the TripleSpec at the Palomar 5-m Telescope, we obtained high quality spectra ranging from 1 to 2.4 micron for a sample of 35 nearby galaxies, for which dynamical black hole masses and optical stellar velocity dispersion measurements are available, in order to calibrate the stellar velocity dispersion in the near-IR. In this poster, we present the initial results based on 10 galaxies, with the stellar velocity dispersion measured in the H-band.

• Mycobiology
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• v.36 no.2
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• pp.93-98
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• 2008

Two Schiff base ligands $L_1\;and\;L_2$ were obtained by the condensation of glycylglycine respectively with imidazole-2-carboxaldehyde and indole-3-carboxaldehyde and their complexes with Zn(II) were prepared and characterized by microanalytical, conductivity measurement, IR, UV-Vis., XRD and SEM. The molar conductance measurement indicates that the Zn(II) complexes are 1:1 electrolytes. The IR data demonstrate the tetradentate binding of $L_1$ and tridentate binding of $L_2$. The XRD data show that Zn(II) complexes with $L_1\;and\;L_2$ have the crystallite sizes of 53 and 61 nm respectively. The surface morphology of the complexes was studied using SEM. The in vitro biological screening effects of the investigated compounds were tested against the bacterial species Staphylococcus aureus, Escherichia coli, Klebsiella pneumaniae, Proteus vulgaris and Pseudomonas aeruginosa and fungal species Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans by the disc diffusion method. A comparative study of inhibition values of the Schiff base ligands and their complexes indicates that the complexes exhibit higher antimicrobial activity than the free ligands. Zinc ions are proven to be essential for the growth-inhibitor effect. The extent of inhibition appeared to be strongly dependent on the initial cell density and on the growth medium.

• Clinical and Experimental Pediatrics
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• v.52 no.3
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• pp.370-375
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• 2009

Purpose : The risk of metabolic syndrome (MS) and cardiovascular disease in Turner syndrome (TS) patients is high. We analyzed metabolic factors in adults with TS and evaluated the metabolic risk of insulin resistance. Methods : Forty-three adults with TS were enrolled. The frequency of MS and the values of the metabolic factors were analyzed. Patients were divided into insulin resistant and non-resistant groups according to values of homeostasis model assessment of insulin resistance (HOMA-IR). The correlations of HOMA-IR with metabolic parameters were analyzed. Results : The frequency of MS was 7% and those of each metabolic parameter were as follows: insulin resistance, 16.3%; central obesity, 15.4%; hypertriglyceridemia, 2.3%; low HDL cholesterol, 9.3%; hypertension, 36.8%. The insulin-resistant group had significantly higher values of body mass index (BMI), waist circumference (WC), fasting plasma glucose (FPG), HOMA-IR, and systolic blood pressure (SBP) than the non-resistant group (P<0.05). HOMA-IR showed a significantly positive correlation with BMI, WC, FPG, and SBP and showed a negative correlation with HDL cholesterol. Conclusion : This study suggests that adults with TS have a high risk of metabolic syndrome, and insulin resistance is correlated with metabolic factors. Therefore, TS patients should have their metabolic parameters monitored regularly to minimize metabolic complications and prevent cardiovascular diseases.

• Journal of Ocean Engineering and Technology
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• v.27 no.3
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• pp.36-42
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• 2013

According to a study on improving ship survivability, an IR signature represents the contrast radiance intensity between the radiation signature from a ship and the background signature. It was found from applying stealth techniques to the process of ship development that the IR signature is remarkably sensitive and dependent on the environment. In this study, marine climate data for the sea near the Korean Peninsula were collected, and the marine meteorological environment in Korean waters was defined. Based on this data, a study on the sensitivity of the IR signature of target objects was performed using analytical methods. The results of the research indicated that clouds have important effects on the infrared signature, but the velocity of the wind and the humidity have only slight effects on the IR signature. In addition, the air and seawater temperatures had hardly any effect on the IR signature, but it is judged that additional study is needed.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.1
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• pp.82.2-82.2
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• 2011

Infra-Red Dark Clouds (IRDCs) seen silhouette against the bright Galactic background in mid-IR are a class of interstellar clouds that are dense and cold with very high column densities. While IRDCs are believed to be the precursors to massive stars and star clusters, individual IRDCs show diverse star forming activities within them. We report a remarkable example of such cloud, the IRDC at ${\Gamma}53.2^{\circ}$, and star formation activity in this cloud. The IRDC was previously identified in part as three separate, arcmin-size clouds in the catalogue of MSX IRDC candidates, but we found that the IRDC is associated with a long, filamentary CO cloud at 2 kpc from the Galactic Ring Survey data of $^{13}CO$ J = 1-0 emission, and that its total extent reaches ~ 30pc. The Spitzer MIPSGAL 24mm data show a number of reddened mid-IR sources distributed along the IRDC which are probably young stellar objects (YSOs), and the UWISH2 $H_2$ data (2.122mm) reveal ubiquitous out flows around them. These observations indicate that the IRDC is a site of active star formation with YSOs in various evolutionary stages. In order to investigate the nature of mid-IR sources, we have performed photometry of MIPSGAL data, and we present a catalogue of YSOs combining other available point source catalogues from optical to IR. We discuss the evolutionary stages and characteristics of YSOs from their IR colors and spectral energy distributions.

• Journal of the Korean Wood Science and Technology
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• v.35 no.1
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• pp.36-43
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• 2007

Elemental analysis, SEM-EDX, X-ray diffraction (XRD) and IR analysis were adopted to examine the quality of charred woods excavated from the underground of the Daewoongjeon Hall of Youngguksa Temple, Youngdong-gun, Chungbuk, Korea. A large amount of calcium was detected in SEM-EDX analysis. The analyses of chemical elements suggested that completely charred wood was carbonized at about $500^{\circ}C$. The XRD results indicated the destruction of cellulose crystalline region. The IR analysis exhibited that thermal degradation of wood component was different depending upon the carbonization temperature. It can be suggested from the results that PEG with different molecular weights should be used for the conservation of excavated charred woods.

• Korean Journal of Chemical Engineering
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• v.36 no.6
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• pp.975-980
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• 2019

Infrared (IR) spectroscopy is a powerful technique for observing organic molecules, as it combines sensitive vibrational excitations with a non-destructive probe. However, gaseous volatile compounds in the air are challenging to detect, as they are not easy to immobilize in a sensing device and give enough signal by themselves. In this study, we fabricated a thin nanocrystalline metal-organic framework (nMOF) film on a surface plasmon resonance (SPR) substrate to enhance the IR vibration signal of the gaseous volatile compounds captured within the nMOF pores. Specifically, we synthesized nanocrystalline HKUST-1 (nHKUST-1) particles of ca. 80 nm diameter and used a colloidal dispersion of these particles to fabricate nHKUST-1 films by a spin-coating process. After finding that benzene was readily adsorbed onto nHKUST-1, an nHKUST-1 film deposited on a plasmonic Au substrate was successfully applied to the IR detection of gaseous benzene in air using surface-enhanced IR spectroscopy.

• Natural Product Sciences
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• v.29 no.2
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• pp.91-97
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• 2023

Mangosteen peel extract is a xanthone group, that plays an important role in anti-angiogenesis. This study investigated mangosteen peel extract on cerebral neovascularization in type 2 diabetes mellitus (DM) rats. This study used 36 rats, randomized into six groups: C1 (negative control); C2 (high fat diet (HFD) and mangosteen peel extract at 200 mg/kg BW); C3 (HFD and diabetic); E1, E2, and E3 (HFD, diabetic, and extract at 100, 200, and 400 mg/kg BW respectively). All groups were measured body mass index (BMI), homeostasis model assessment-insulin resistance (HOMA-IR) and β cell function (HOMA-B), and histopathological feature of cerebral vascular (CV). There were significant differences in BMI, HOMA-IR, HOMA-B, and the mean number of CV (all p < 0.05) among treatment groups. E1-3 groups had a significantly lower level of blood glucose and HOMA-IR, and a higher level of HOMA-B and BMI (all p < 0.05) which tends to reduce cerebral neovascularization. HOMA-IR independently had a positive effect to induce neovascularization of CV (p < 0.05, R² = 26.8%). These findings suggested that mangosteen peel extract increased β-cell function sensitivity, and effectively suppressed insulin resistance, BMI, and cerebral neovascularization process in type 2 DM rats.