• Conservation Science in Museum
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• v.8
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• pp.49-69
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• 2007

This is about the scientific analysis of the 10 items of the gilt-bronze Panbul excavated from Anapji, Gyeongju. First, the composition of the Panbul was confirmed, using X-ray fluorescence spectrometer (XRF), and the patinas covering the surface of the Panbul were analyzed, using X-ray diffractometer (XRD). And the micro structures and gilt layer of the Panbul were investigated, using microscope and scanning electron microscope with energy dispersive spectrometer (SEM/EDS), and in order to investigate the internal conditions of the Panbul, X-radiography was conducted. As the result, it is found out that the material of the Panbul excavated from Anapji was the bronze of copper (86~95%) and tin (4~12%), and coated with gold. And cuprite (Cu₂O) was detected from red patina of the gilt-bronze Panbul, and chalcocite(Cu₂S) also was detected from the black patina. As the result of the observation of the micro structure through microscope, it is estimated that it was manufactured, using the wax molding method, and, judging from the fact that the thickness of gilt layer was not even, and that the groove had been filled, it was presumed that the amalgam coating method had been used, but some questions still remain, because mercury was not detected. Lastly, through the X-radiography, it was observed that the tiny round spots existed, which was presumed to have been generated during the casting.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.135-140
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• 2008

In this study, the macromineral content ratios of four herbal medicine samples(Saposhnikoviae Radix, Bupleuri Radix, Cnidii Rhizoma, and Astragali Radix) were analyzed to discriminate their geographical origins using an energydispersive x-ray fluorescence (EDXRF) technique. EDXRF is a rapid, non-destructive, and multi-elemental analysis technique. Initially, samples of both domestic and imported herbal medicines were pulverized, and then their macromineral contents, including P, S, K, and Ca, were analyzed using EDXRF. For the discrimination of their geographical origins, canonical discriminant analysis was carried out based on the estimated macromineral relative content ratios of the samples. According to the results, the discrimination accuracies were as follows: 93.3% for Saposhnikoviae Radix, 95.7% for Bupleuri Radix, 98.8% for Cnidii Rhizoma, and 87.5% for Astragali Radix. Overall, the results imply that this technique could be used as a standard method, to discriminate their geographical origins between domestic and imported herbal medicines.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.3
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• pp.229-234
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• 2001

The EDXRF(Energy Dispersive X-ray Fluorescence Spectrometer) technique was applied to the determination of heavy metals in welding fume. The EDXRF method designed in this study was a non-destructive analysis method. Samples were analyzed directly by EDXRF without any pre-treatment such as digestion and dilution. The samples used to evaluate this method were laboratory samples exposed in a chamber connected with a welding fume generator. The samples were first analyzed using a non-destructive EDXRF method. The samples subsequently were analyzed using AAS method to verify accuray of the EDXRF method. The purpose of this study was to evaluate the possibility of the non-destructive analysis of heavy metals in welding fume by EDXRF. The results of this study were as follow: 1.When the samples were collected under the open-face sampling condition, a surface distribution of welding fume particles on sample filters was uniform, which made non-destructive analysis possible. 2. The method was statistically evaluated according to the NIOSH(National Institute for Occupational Safety and Health) and HSE(Health and Safety Executive) method. 3. The overall precision of the EDXRF method Was calculated at 3.45 % for Cr, 2.57 % for Fe and 3.78 % for Mn as relative standard deviation(RSD), respectively. The limits of detection were calculated at $0.46{\mu}g$/sample for Cr, $0.20{\mu}g$/sample for Fe and $1.14{\mu}g$/sample for Mn, respectively. 4. A comparison between the results of Cr, Fe, Mn analyzed by EDXRF and AAS was made in order to assess the accuracy of EDXRF method. The correlation coefficient between the results of EDXRF and AAS was 0.9985 for Cr, 0.9995 for Fe and 0.9982 for Mn, respectively. The overall uncertainty was determined to be ${\pm}12.31%$, 8.64 % and 11.91 % for Cr, Fe and Mn, respectively. In conclusion, this study showed that Cr, Fe, Mn in welding fume were successfully analyzed by the EDXRF without any sample pre-treatment such as digestion and dilution and a good correlation between the results of EDXRF and AAS was obtained. It was thus possible to use the EDXRF technique as an analysis method of working environment samples. The EDXRF method was an efficient method in a non-destructive analysis of heavy metals in welding fume.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.7
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• pp.472-478
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• 2013

Cu and Cr as a base metal and Pt, Pd as a supportive metal were selected for improving adsorption capacity of activated carbon fiber in eliminating especially targeted VOCs. Preparing variables such as metal loading, loading temperature, loading hours and kinds of loaded metals were changed. Properties measurement was carried out by SEM (scanning electron microscope), XRF (x-ray fluorescence analysis) and EDX (Energy Dispersive X-ray spectrometer) and adsorption capacity evaluation were also performed by gas analyzer. Under this study, the adsorption capacity of complex metal loaded activated carbon fiber was improved positively than that of single metal loaded activated carbon fiber. And we found that the best conditions for metal loading were 5 hours loading time at $100^{\circ}C$ and the adsorption capacity was enhanced almost double compared with other condition based activated carbon fiber. Cu-Cr-Pt-Pd loaded activated carbon fiber showed the best adsorption capacity. Also we confirmed that more than 0.5 second is necessary for adsorbate diffusion and adsorption over activated carbon fiber.

• Conservation Science in Museum
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• v.26
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• pp.67-82
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• 2021

Two golden beads (Buyeo 5336) housed at the Buyeo National Museum were discovered in 1993 near the site of an ancient workshop in Neungsan-ri in Buyeo-gun, Chungcheongnam-do Province. These rare examples from the Baekje Kingdom of an application of granulation have maintained their original form intact, and thus serve as important materials for the investigation of production techniques applied. This study analyzed the composition of the golden beads using a portable X-ray fluorescence analyzer, a stereo microscope, and a scanning electron microscope with an energy dispersive X-ray spectrometer. The manufacturing technique was examined through the observation of the micro-shape and the surface condition and by a composition analysis of the joint part. In both beads, a hole was pierced in a hollow body and the bead was decorated with golden wires around the hole and gold granules in other parts. In some areas, golden granules had been attached to the gold plate and golden wires were then placed over the granules. The purity of both the wires and the granules was analyzed as 23.6 - 23.7K. A high copper content was detected in some of the parts where the granules were attached. The findings of a previous reproduction experiment and study of production methods suggest that the beads were made using the copper diffusion technique.

• Journal of the Korean Chemical Society
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• v.66 no.2
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• pp.78-85
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• 2022

Natural white clay was treated with 6 M of H₂SO₄ and heated at 80℃ for 6 h under mechanical stirring and the resulting acid active clay was used as an adsorbent for the removal of Cs⁺ in water. The physicochemical changes of natural white clay and acid active clay were observed by X-ray Fluorescence Spectrometry (XRF), BET Surface Area Analyser and Energy Dispersive X-line Spectrometer (EDX). While activating natural white clay with acid, the part of Al₂O₃, CaO, MgO, SO₃ and Fe₂O₃ was dissolved firstly from the crystal lattice, which bring about the increase in the specific surface area and the pore volume as well as active sites. The specific surface area and the pore volume of acid active clay were roughly twice as high compared with natural white clay. The adsorption of Cs⁺ on acid active clay was increased rapidly within 1 min and reached equilibrium at 60 min. At 25 mg L^- of Cs⁺ concentration, 96.88% of adsorption capacity was accomplished by acid active clay. The adsorption data of Cs⁺ were fitted to the adsorption isotherm and kinetic models. It was found that Langmuir isotherm was described well to the adsorption behavior of Cs⁺ on acid active clay rather than Freundlich isotherm. For adsorption Cs⁺ on acid active clay, the Langmuir isotherm coefficients, Q, was found to be 10.52 mg g^-1. In acid active clay/water system, the pseudo-second-order kinetic model was more suitable for adsorption of Cs⁺ than the pseudo-first-order kinetic model owing to the higher correlation coefficient R² and the more proximity value of the experimental value q_e,exp and the calculated value q_e,cal. The overall results of study showed that acid active clay could be used as an efficient adsorbent for the removal of Cs⁺ from water.