• Korean Journal of Crystallography
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• v.1 no.2
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• pp.61-65
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• 1990

Smoky quartz was grown hydrothermally. For the establishment of the best growth condition, various growth factors, such as nutrients, seed orientations, minerlizers, colorants and irradiation times were studied. By the UV-visible spectrum analysis synthetic and natural smoky quartz were characterized. As a result, smoky quartz of 120mm L X 35mm W X 14mm T with clear color tone and minimum defect was grown.

• Journal of The Korean Astronomical Society
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• v.32 no.1
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• pp.55-63
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• 1999

NGC 6537 is an extremely high excitation bipolar planetary nebula. It exhibits a huge range of excitation from lines of [N I] to [Si VI]or [Fe VII], i.e. from neutral atoms to atoms requiring an ionization potential of $\~$167eV. Its kinematical structures are of special interest. We are here primarily concerned with its high resolution spectrum as revealed by the Hamilton Echelle Spectrograph at Lick Observatory (resolution $\~0.2{\AA}$) and supplemented by UV and near-UV data. Photoionization model reproduces the observed global spectrum of NGC 6537, the absolute H$\beta$ flux, and the observed visual or blue magnitude fairly well. The nebulosity of NGC 6537 is likely to be the result of photo-ionization by a very hot star of $T_{eff} \~ 180,000 K$, although the global nebular morphology and kinematics suggest an effect by strong stellar winds and resulting shock heating. NGC 6537 can be classified as a Peimbert Type I planetary nebula. It is extremely young and it may have originated from a star of about 5 $M_{\bigodot}$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.75-78
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• 1994

Organic ultra thin films about 500${\AA}$ in thickness are fabricated by LB(Langmuir-Blodgett) technique and their gas detect properties are investigated. The LB films deposited are made of the specimen named as N-docosyl pyridinium(TCNQ) and the deposition is verified by capacitance conductivity measurement. From the study of gas detect properties with I-V characteristics and UV spectrum we have found that their conductivities were increased about 3 times of magnitude and peaks of UV spectrum were decreased.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.316-316
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• 2010

Six metal-free organic dyes having thiophene (1), benzene-thiophene (2), thiophene-benzene (3), thiophene-pyridine(4), thiophene-thiophene (5), and pyridine (6) linkers between 9,9-dimethylfluorenyl terminal group and $\alpha$-cyanoacrylic acid anchor were synthesized. Among them, organic dye 5 showed the longest ${\lambda}}max$ value (424 nm) in UV-Vis absorption spectrum, better incident monochromatic photon-to-current conversion efficiency (IPCE), highest short circuit photocurrent density (JSC, 9.33 mA2/cm2), and highest overall conversion efficiency ($\eta$, 3.91%).

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.828-831
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• 1999

5,15-Bis(mesityl)-10,20-bis(4-amino)porphyrin was synthesized with meso-(mesityl)dipyrromethane and 4-nitrobenzaldehyde. It was characterized with $^1H$-NMR spectroscopy, UV spectrophotometer, and GC-MASS. In UV spectrum, Soret-band(438 nm) and Q-bands(526, 572, 611 nm) were confirmed. In NMR spectrum, the characteristic peak of porphyrin was detected at -2.65 ppm. Copolyimide containing porphyrin structure was synthesized with mesityl-$TPP(NH_2)$, 3,3',4,4'-benzophenonetetracarboxylic dianhydride(BTDA) and 2,2-bis(4-(4-aminophenoxy)phenyl) hexafluoropropane(BAPHF) and characterized with UV and FT-IR spectrophotometer. The $T_g$ and $T_m$ of the synthesized copolyimide were 220.7 and $369.2^{\circ}C$, respectively.

• Journal of the Korean Society of Safety
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• v.16 no.1
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• pp.1-8
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• 2001

All objects emit thermal radiation and this radiation is the basis of the techniques used to detect flames. The usual phenomena occurring in the initial stage of the fire are generally invisible products of a combustion and visible smoke. Liquid or gaseous materials do not undergo a smoldering stage so that fires develop very rapidly. Also, the heat generated by the initial flames is usually not sufficient to activate a heat detector. In this case the most effective criterion for automatic fire detection is the flame. According to the fire regulation of korea, the compulsory standard provided that a flame detector shall be installed in a place that the attachment height of detector is higher than 20 m, chemical plants, hangar, refinery, etc.. The results of the research and development are discriminated between a flame and other radiant emitters, developed a UV detector tube contains an inert gas which absorbs UV radiation, developed PZT pyroelectric element is based on the use of photovoltanic cell, developed IR band-pass filter that only allow a 4.3 $\mu\textrm{m}$ radiation wavelength to reach the sensors and developed UV-IR combination flame detector combined into a single detection device.

• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.59-64
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• 2002

The photocatalytic decolorization of the Rhodamine B (RhB) was studied using a UV/TiO$_2$ reactor. Yakuri titanium dioxide(anatase) was used as the suspended photocatalyst and proved to be effective for decolorization irradiated with UV light (254 mm). The photocatalyzed dioxide concentrations, light intensity and air flow rates. In 0.01 mM RhB, color could be completely photodegraded after 3 hours. Absorption spectrum of an aqueous solution containing RhB showed a continued diminution of the RhB concentration in the solution bulk : concomitantly, no new absorption peaks appeared. This confirmed the decolorization of RhB, i.e., the break up of the chromopore. The optimum loaded titanium dioxide for the decolorization was 0.75 g/(equation omitted). The light intensity showed exponential decay with distance. The decay of light intensity of RhB solution showed different tendency from TiO$_2$. These results suggested that the photocatalytic decolorization of dyes may be available method for decolorizing in wastewater.

• Journal of the Korean Ceramic Society
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• v.30 no.10
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• pp.797-802
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• 1993

Graphite fiber intercalated compound was deintercalated at $25^{\circ}C$, 65% of humidity and its deintercalated compound was discussed, based on the X-ray diffraction analysis, electrical resistivity measurement, and UV/VIS spectrometer measurements. During deintercalation, the structure was changed in orderlongrightarrowdisorderlongrightarroworder, and resistivity was decreased in the disorder state of the structure, which reflectance minimum of the UV/VIS spectrum ranged from 660 to 750nm (1.88~1.65eV).

• The Korea Journal of Herbology
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• v.23 no.1
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• pp.109-116
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• 2008

Objectives : This study was performed to investigate the discriminative criteria of 6 kinds of Achyranthis Radix by HPLC/DAD. Methods : 20-hydroxyecdysone is isolated by silica gel column chromatography ($CHCl_3$:MeOH, 7:1-1:1 v/v) and identified by nuclear magnetic resonance, A high-performance liquid chromatographic method with diode array detection was used to identify 20-hydroxyecdysone in A. japonica. The analysis was performed using $C_{18}$ column with isocratic elution consisted of 18% acetonitrile and 82% water and the detection was carried out by DAD at 254 nm. 6 kinds of Achyranthis Radix from different locations were extracted in MeOH. Each extracts was analyzed by HPLC in same condition as used in analysis of 20-hydroxyecdysone. The identities of each extracts were determined by comparing the retention time and UV spectrum with that of reference compound. Results : 1. A. japonica and A. bidentata showed the similar patterns of HPLC chromatogram and 20-hydroxycedysone was present in both of them because the peaks having the same retention time and UV spectrum as 20-hydroxyecdysone were shown in the HPLC chromatograms of A. japonica and A. bidentata 2. Cyathula officinalis and C. capitata showed the similar patterns of HPLC chromatogram. The peak having the same retention time and UV spectrum as 20-hydroxyecdysone was shown in the HPLC chromatogram of C. capitata but not shown in the HPLC chromatogram of C. officinalis. 3. Two species of medicinal drugs from Sacheon province showed similar patterns of HPLC chromatogram. Achyranthis Radix from Sacheon(wild) did not have 20-hydroxycedysone but Achyranthis Radix from Sacheon(cultivated) showed the peak having the same retention time as 20-hydroxyecdysone but UV spectrum of the peak was different from that of 20-hydroxyecdysone. Conclusions : These results suggested that 20-hydroxyecdysone could be the discriminative criteria for Achyranthis Radix contain 20-hydroxyecdysone though they belong to different genus and species. And the patterns of HPLC chromatogram also could be the discriminative criteria as the different species of Achyranthis Radix belonging to the same genus showed similar patterns of HPLC chromatogram.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.723-727
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• 2002

Conformational changes of allivin, a major allergen protein in garlic, by gamma irradiation were observed. Allium solution (3.0 mg/mL in 0.01 M PBS, pH 7.4) and raw garlic were irradiated in a gamma irradiation facility to be absorbed with doses of 2.5, 5.0, 7.5 and 10.0 kGy. After irradiation, a half of irradiated allivin solution was filtered through 0.22 ${\mu}{\textrm}{m}$ filtration kit. UV spectrum and SDS-PAGE were used for observing the conformational changes of allivin by gamma irradiation. Turbidity of allivin solution was increased by optical observation, and the result was validated by the increase of absorbance at 660 m. Turbidity of irradiated and filtered allivin solution significantly (p<0.05) decreased, and the concentration of soluble protein in the solution decreased by increase of the dose. Aggregation among allivin molecules was observed by SDS-PAGE, but irradiated and filtered samples showed decrease of allivin with reducing aggregation trend. SDS-PAGE profiles of irradiated raw garlic were not different. Results indicate that gamma irradiation can decrease the allivin in solution state which may impact on allergenic reaction of garlic.