• YAKHAK HOEJI
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• v.50 no.3
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• pp.154-159
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• 2006

For the increasing demand for the validation of analytical results, one of the important concerns of the analyst is to be assured that the instrumentation is working to qualified conditions. In this study, we have investigated and compared several validation guidelines of the performance verification of UV-VIS spectrophotometer used in pharmacopoeias of major countries and UV-VIS instrument analytical companies, and we proposed the practically useful validation guidelines of UV-VIS spectrophotometer. Based on our proposed validation guidelines of UV-VIS spectrophotometer, several UV-VIS spectrophotometers used in drug manufacturing laboratories were validated for their performances.

• Analytical Science and Technology
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• v.7 no.1
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• pp.17-23
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• 1994

Through sol-gel process, inorganic/organic composite as a dye host was made. It was observed that this composite has about 90% of trnasmittance by UV/VIS spectrophotometer. The transmittance is the most important requirement to decide whether the composite could apply or not as the dye host. The transmittance was increased with decreasing HCl as a catalyst, aging time, and amount of PDMS. Also, fluorescent and transmittant charateristics of Rhodamine 6G Perchlorate that was doped into ORMOSIL were measured. The fluorescent intensity was increased and the trnasmittance was decreased with rising gelling temperature.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1657-1661
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• 2011

In this study, CdSe-$TiO_2$ photocatalyst were synthesized by a facile solvothermal method and characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis and UV-vis diffuse reflectance spectrophotometer. The photocatalytic activity was investigated by degrading methylene blue (MB) in aqueous solution under irradiation of UV light as well as visible light. The absorbance of degraded MB solution was determined by UV-vis spectrophotometer. The results revealed that the CdSe-$TiO_2$ photocatalyst exhibited much higher photocatalytic activity than $TiO_2$ both under irradiation of UV light as well as visible light.

• Analytical Science and Technology
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• v.18 no.5
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• pp.425-430
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• 2005

In this study, we investigated the performance of a portable colorimeter used for the measurements of atmospheric ammonia against the more reliable method like UV/VIS spectrophotometer. For the purpose of this study, we tested a portable colorimeter and UV/VIS spectrophotometer for such basic analytical parameters as detectibility, reproducibility, linearity, and accuracy. According to our study, the performance of the colorimeter was fairly good to show a good agreement with the UV/VIS system. However, the performance of colorimeter suffered from both low and high concentration ranges: it was found to have very poor reproducibility at lower concentration (below $10\mu}g$), while its linear dynamic range was limited at the upper end (e.g., near $100{\mu}g$). If we assume that air samples are collected up to 30 liter, it implies that the colorimeter can be used to measure samples containing NH3 in the range of 500 ppb to 5 ppm (without the aid of diluting technique). Consequently, we recommend the use of such instrument with the awareness of its basic properties pertaining to the fundamental performance (such as its detectable range).

• Applied Chemistry for Engineering
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• v.21 no.3
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• pp.306-310
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• 2010

Petroleum visible markers (dye) have been used to distinguish different fuel classes and to prevent illegal mixing. It is difficult to recognize the real color of visible marker when the small amount of petroleum product was mixed in another fuel oil. In this study, we determined the two wavelengths (370 nm, 645 nm) which detect all Korean petroleum visible marker using UV/Vis spectrophotometer. Then we analyzed the visible marker using high performance liquid chromatography (HPLC) in two wavelength detectors. Also, we optimized the analytic method for petroleum visible marker in illegal mixed fuel oil.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.5
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• pp.369-371
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• 2003

Cyanidin 3-glucoside (C3G) content contained in the grains of blackish purple rice varieties, Heugjinjubyeo, Kilimheugmi, Heugnambyeo, Sanghaehy-anghyeolla, and the progenies derived from their crosses was evaluated by HPLC and UV-Vis spectroscopy. C3G content was higher in the range of 10-30% by using UV-Vis method compared to HPLC method. A significant linear relationship was, however, observed between two analytical methods. The correlation coefficient was 0.98. Thus, this results suggested that it would be able to use UV-Vis spectroscopy to determine C3G content which does not demanded precise value like selection.

• Elastomers and Composites
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• v.53 no.2
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• pp.75-79
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• 2018

ZnS:Mn-glycine (ZnS:Mn-Gly) nanocomposites were synthesized by capping ZnS:Mn nanocomposites with glycine. Zinc sulfate heptahydrate ($ZnSO_4{\cdot}7H_2O$), glycine ($C_2H_5NO_2$), manganese sulfate monohydrate ($MnSO_4{\cdot}H_2O$), and sodium sulfide ($Na_2S$) were used as the source reagents. $ZnS:Mn-Gly-C_{60}$ nanocomposites were obtained by heating the ZnS:Mn-Gly nanocomposites and fullerene ($C_{60}$) at a 2:1 mass ratio in an electric furnace at $700^{\circ}C$ for 2 h. X-ray diffraction (XRD) was used to characterize the crystal structure of the synthesized nanocomposites. The photocatalytic activity of the $ZnS:Mn-Gly-C_{60}$ nanocomposites was evaluated, via the degradation of brilliant green (BG) dye under 254 nm irradiation, with a UV-vis spectrophotometer.

• KSBB Journal
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• v.5 no.2
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• pp.191-194
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• 1990

Tyrosine is a monohydrolic aromatic amino acid and DOPA is a tyrosine derivative containing dihydroxy group. DOPA can be synthesized from tyrosine by enzymatic reaction. The separation and quantitative determination of each component are very difficult in the reaction mixture. In the present study, two wavelengths giving maximum absorbance difference of each amino acid were determined using UV/VIS spectrophotometer by wavelength scanning and simple assay method was developed for the analysis of the reaction mixture of tyrosine and DOPA by measuring absorbances of reaction mixture. This method can be simply used for the analysis of the tyrosine and DOPA mixture because it does not require and procedure for the pretreatment of the reaction mixture.

• Journal of the Korea Society of Computer and Information
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• v.7 no.3
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• pp.36-41
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• 2002

This study was carried out develope a ultrasonic transducer displacement generator through 26KHz and 38KHz of the frequency phase modulation on the ultrasonic transducer. This system was producted a power output generation such as 100W, 300W, 400W and 600W. Ultrasonic power output had a change of time. We made use of a Thiram hydration and detected it measurement by the ACAO method. It was to decide the result of ultrasonic power supply for time duration and the result of comparison in the 26KHz & 38KHz by UV/VIS spectrophotometer.

• Textile Coloration and Finishing
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• v.21 no.6
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• pp.39-45
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• 2009

The importance of nano gold particles has been increased in the field of bio physics and medicine, recently. In this regard, the study aims to analyze how the harmless nano gold particles can be transformed by respective variables. In this study, electrospun PU nano-webs were impregnated with aqueous $HAuCl_4$ solution and UV light was irradiated on the webs. Au-ions were reduced to nano particles by photocatalytic reduction and these nano gold particles were characterized by SEM, UV-vis, Zetasizer, Spectrophotometer, EDS. $HAuCl_4$ solution concentration and UV irradiation time have heen examined to change the amount of absorption. Nano gold particles size and UV-Vis absorbances were increased with $HAuCl_4$ solution concentration and UV irradiation time.