• Korean Journal of Remote Sensing
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• v.34 no.3
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• pp.481-494
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• 2018

The accurate radiative transfer model simulation is essential for an accurate ozone profile retrieval using optimal estimation from backscattered ultraviolet (BUV) measurement. The input parameters of the radiative transfer model are the main factors that determine the model accuracy. In particular, meteorological parameters such as temperature and surface pressure have a direct effect on simulating radiation spectrum as a component for calculating ozone absorption cross section and Rayleigh scattering. Hence, a sensitivity of UV ozone profile retrievals to these parameters has been investigated using radiative transfer model. The surface pressure shows an average error within 100 hPa in the daily / monthly climatological data based on the numerical weather prediction model, and the calculated ozone retrieval error is less than 0.2 DU for each layer. On the other hand, the temperature shows an error of 1-7K depending on the observation station and altitude for the same daily / monthly climatological data, and the calculated ozone retrieval error is about 4 DU for each layer. These results can help to understand the obtained vertical ozone information from satellite. In addition, they are expected to be used effectively in selecting the meteorological input data and establishing the system design direction in the process of applying the algorithm to satellite operation.

• Journal of the Korean Society of Radiology
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• v.9 no.1
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• pp.39-45
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• 2015

$La_2W_3O_{12}:Eu^{3+}$ phosphors were prepared by solid state reaction method. The crystal structure was characterized by XRD pattern and ICSD card (78180). Luminescence properties of $La_2W_3O_{12}:Eu^{3+}$ are investigated by optical and laser-excitation spectroscopy in which emission and excitation spectra and time-resolved spectra are measured. The 1 mol % $Eu^{3+}$-doped $La_2W_3O_{12}$ phosphor exhibits broad excitation band peaking at 286 nm due to the ligand-to-metal charge transfer transition. The excitation lines due to the $^7F_0{\rightarrow}{^5D_4},{^5D_4},{^5L_6},{^5G_4},{^5D_3},{^5D_2}$ transitions of $Eu^{3+}$ are observed in the wavelength region 350-500 nm. The strong line emission is observed at 618 nm corresponding to the due to the $^5D_0{\rightarrow}^7F_2$ transition. The lifetime of 618 nm emission decreases with increasing temperature as 7 K ($114{\mu}s$), 100 K ($94{\mu}s$), 200 K ($10{\mu}s$) and 300 K ($0.5{\mu}s$).

• Journal of the Korean Vacuum Society
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• v.20 no.5
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• pp.361-366
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• 2011

An in-situ, real-time monitoring of GaN epilayers grown by low pressure metalorganic chemical vapor deposition system modified for spectral reflectance was performed. Reflectance spectrums from 190~861 nm were observed using p-polarized light with incident angle of $75^{\circ}$. All reflectance spectrums showed interference oscillation caused by multiple reflection within GaN epilayers, and the spectrum from GaN with low crystalline quality showed weak reflectance intensity and much low amplitude of the oscillation because many defects in GaN resulted in light scattering and absorption. Signal variation of reflected light which was selected around strong constructive wavelength range was also observed during $NH_3$ supplying and $NH_3$ cut-off. There was no significant change in signal intensity when $NH_3$ cut-off for 10 sec, but it showed higher intensity when $NH_3$ was cut off for over 30 sec and its intensity kept unchanged. This result indicates that GaN surface was N-terminated during $NH_3$ supplying but Ga-terminated during $NH_3$ cut-off because of high nitrogen equilibrium vapor pressure of GaN, and metallic Ga-terminated surface caused slightly higher reflectance intensity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.417-421
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• 2018

Carboxytherapy is very similar to mesotherapy in terms of methods, conditions it treats, and outcomes. An important difference consider, however, is that carboxytherapy administers carbon dioxide gas into the subcutaneous layer, just underneath the skin, whereas mesotherapy administers a cocktail of vitamins, minerals, and drugs and into the mesoderm of the skin. There have been many previous case reports of complications of mesotherapy such as hematoma, granulomatous panniculitis, cellulitis, and abscesses. However, complications of carboxytherapy have rarely been reported because the carbon dioxide gas is absorbed within a week and is infused into the subcutaneous and superficial layers. A 27-year-old woman who had twice undergone carboxytherapy to reduce abdominal fat (3 days and 2 weeks ago) at an oriental medical clinic visited the emergency department due to high fever, myalgia, severe back pain, and subcutaneous emphysema from the buttocks to the lower chest wall area. A computed tomography (CT) scan was performed for diagnosis and treatment. We immediately started broad spectrum antibiotics and consulted with the department of radiology, which could not rule out acute peritonitis due to needle injury. A radiologist confirmed abdominal myositis and needle puncture induced acute pyelonephritis. Pyelonephritis can even lead to septicemia, which can have fatal consequences. Therefore, if the patient has costovertebral or back pain after undergoing needle puncture or acupuncture therapy, the emergency physcians need careful initial evaluation for diagnosis and treatment.

• Journal of Conservation Science
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• v.28 no.3
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• pp.277-283
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• 2012

This study conducted analysis of paint samples from a streetcar No. 381 (Registration Cultural Property No. 467) to identify the characteristics of the modern paint. The samples were analyzed by Microscopic observation, infrared spectroscopy and SEM-EDS. The upper part is consist of 26 layers and the under part is 29 layers. And the layers were painted various thickness from $10{\mu}m$ to $100{\mu}m$, and confirmed that several color had been used. The putty was used for surface treatment before painting. According to the results of infrared spectroscopy, paint specimens were identified as alkyd resin. Some bands such as C-H and C=O stretcing, aromatic, C-H bending, C-O stretching were found in spectra. Inorganic analysis showed that gold color on the surface was used copper-based paint. And type of the putty was lacquer-putty that was consist of kaolin, talc and zinc white.

• Analytical Science and Technology
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• v.24 no.4
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• pp.256-265
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• 2011

Ambers have been used as a gemstone and a religious object since the ancient times and found in several archaeological sites in Korea. To prepare an enhanced conservation measures, we surveyed the chemical and spectroscopic properties of the ambers according to the provenance. Total 14 amber samples were collected from 6 different provenances including Baltic, Chiapas, Colombian, Dominican, Fushun and Madagascar amber. Infrared (IR) spectroscopic analysis was conducted for the non-destructive examination of the amber samples. They were also analyzed with pyrolysis/GC/MS (py/GC/MS) at the pyrolysis temperature of $300^{\circ}C$ with the on-line derivatization to trimethylsilyl ester. Baltic shoulder corresponding to the absorption at $1250cm^{-1}{\sim}1150cm^{-1}$ appeared in the IR spectrum of Baltic amber. IR spectra of the other ambers also showed somewhat distinctive characteristic peaks. In py/GC/MS analysis peaks assignable to succinic acid, dehydroabietic acid and pimaric acid were detected, which are known to be the components of the amber. In the meanwhile, the presence of compounds appearing in certain amber will be applied to differentiate the provenances of amber relics if their fragments are available for the analysis. These results are expected to help the confirmation of archaeological amber relics and archaeometric interpretation of provenances and manufacturing techniques.

• Microbiology and Biotechnology Letters
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• v.46 no.2
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• pp.120-126
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• 2018

As a basic study for environment-friendly production of bacterial cellulose (BC) dressing with antimicrobial activity, we isolated and identified acetic acid bacteria which are resistant to silver ions and can biosynthesize silver nanoparticles. Furthermore, conditions of BC production by selected strain were also investigated. Strain G7 isolated from decayed grape skin was able to grow in the presence of 0.1 mM $AgNO_3$ which was identified as Acetobacter intermedius based on 16S rRNA gene analysis. BC production was the highest in a medium containing 2% glucose as a carbon source, 2% yeast extract as a nitrogen source, and 0.115% acetic acid as a cosubstrate. Structural properties of BC produced in optimal medium were studied using Fourier-transform infrared spectroscopy and X-ray diffractometer, and it was found that BC produced was cellulose type I that was the same as a typical native cellulose. When strain G7 was cultured in an optimal medium containing 0.1 mM $AgNO_3$, the color of the culture broth turned into reddish brown, indicating that silver nanoparticles were formed. As a result of UV-Vis spectral analysis of the culture, it was found that a unique absorption spectrum of silver nanoparticles at 425 nm was also observed. Scanning electron microscopic observations showed that silver nanoparticles were formed on the surface and pores of BC membrane.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.1
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• pp.71-76
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• 2008

Purpose: A simple and efficient method to prepare nanocrystalline ZnO thin film with pure strong UV emission on soda-lime-silica glass substrates by low-temperature annealing was improved. Methods: Crystal structural, surface morphological, and optical characteristics of nanocrystalline ZnO thin films deposited on soda-lime-silica glass substrates by prefiring final annealing process at 300$^{\circ}C$ were investigated by using X-ray diffraction analysis, field emission-scanning electron microscope, scanning probe microscope, ultraviolet-visible-near infrared spectrophotometer, and photoluminescence. Results: Highly c-axis-oriented ZnO films were obtained by prefiring at 300$^{\circ}C$. A high transmittance in the visible spectra range and clear absorption edge in the ultra violet range of the film was observed. The PL spectrum of ZnO thin film with a deep near band edge emission was observed while the defect-related broad green emission was nearly quenched. Conclusions: Our work will be possibly adopted to cheaply and easily fabricate ZnO-based optoelectronic devices at low temperature, below 300$^{\circ}C$, in the future.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.564-569
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• 1992

A green sulfur bacterium, Chlorobium limicola f. thiosulfatophilum NCIB 8327, was grown in modified Pfennig's medium including glu1amate as a nitrogen source. Glutamine synthetase was isolated through a series of ultracentrifugation. DEAE-Sepharose CL-6B ion exchange chromatography. Sephacryl S-300 gel permeation chromatography, and preparative HPLC. The recovery and purification fold of the enzyme were 2% and 46.3. respectively. The isolated enzyme was homogeneous on UV-Visible spectrum and polyacrylamide gel electrophoretogram. The relative molecular mass of the native enzyme was estimated to be 280,000 by gel permeation chromatography. The enzyme consisted of ten subunits with relative similar molecular mass. 30.000. which was estimated by SDS-polyacrylamide gel electrophoresis. The optimal temperature and pH of the enzyme were $30^{\circ}C$ and 7.0. Km values were 27.9 mM for L-glutamine and 0.92 mM for hydroxylamine-HCr. The enzyme activity was inhibited by alanine. glycine. and tryptophan considerably, but was not affected by asparagine, lysine. leucine. and valine.

• Progress in Medical Physics
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• v.9 no.1
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• pp.55-64
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• 1998

In recent, the demand of development of the high dose rate brachytherapy source increased for substitute for Co-60 source by iridium source, since the supplying Co-60 source is very depressed and the high dose rate brachytherapy sources are entirely imported from the abroad. This study investigated the exposure rates and isotropic dose distributions for the Ir-192 source produced from $\^$191/Ir(n,r)$\^$192/Ir by nuclear reactor in Korea Atomic Energy Research Institute. The activity of source was obtained an 1.012 Ci (the initial activity without encapsulation was 2,87Ci) by measurement with encapsuled stainless steel. The exposure rate of provided Ir-192 source was determined on 6.36 ${\pm}$ 0.147 Rm$^2$/h-GBq (2.350 ${\pm}$ 0.054 Rcm$^2$/mCi-hr) within ${\pm}$ 2.2% discrepancy with IC-10 ion chamber (0.14 cc) which was mounted on the acrylic jig to 5, 10 and 20 cm from the center of source. The calculated doses with 22 most significant spectrum lines were corrected with intrinsic efficiency of the germanium detector were compared to measured exposure dose rates within ${\pm}$3.8 % discrepancy. The authors confirmed the high dose rate Ir-192 source could be replaced the long decayed Co-60 source via investigation of the isotropic dose distributions in lateral, source axis and diagonal direction of source center are very closed to within 3% uncertainties. Especially, this exposure rate constant and isotropic dose distribution will be fundamental to build the high dose rate source and develop the computed therapy planning system.