• Journal of Radiation Protection and Research
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• v.41 no.4
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• pp.359-367
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• 2016

Background: As new legislation has come into force implementing radiation safety management for the use of naturally occurring radioactive materials (NORM), it is necessary to establish a rapid and accurate measurement technique. Measurement of $^{238}U$ and $^{232}Th$ using conventional methods encounter the most significant difficulties for pretreatment (e.g., purification, speciation, and dilution/enrichment) or require time-consuming processes. Therefore, in this study, the applicability of ED-XRF as a non-destructive and rapid screening method was validated for raw materials and by-product samples. Materials and Methods: A series of experiments was conducted to test the applicability for rapid screening of XRF measurement to determine activity of $^{238}U$ and $^{232}Th$ based on certified reference materials (e.g., soil, rock, phosphorus rock, bauxite, zircon, and coal ash) and NORM samples commercially used in Korea. Statistical methods were used to compare the analytical results of ED-XRF to those of certified values of certified reference materials (CRM) and inductively coupled plasma mass spectrometry (ICP-MS). Results and Discussion: Results of the XRF measurement for $^{238}U$ and $^{232}Th$ showed under 20% relative error and standard deviation. The results of the U-test were statistically significant except for the case of U in coal fly ash samples. In addition, analytical results of $^{238}U$ and $^{232}Th$ in the raw material and by-product samples using XRF and the analytical results of those using ICP-MS ($R^2{\geq}0.95$) were consistent with each other. Thus, the analytical results rapidly derived using ED-XRF were fairly reliable. Conclusion: Based on the validation results, it can be concluded that the ED-XRF analysis may be applied to rapid screening of radioactivities ($^{238}U$ and $^{232}Th$) in NORM samples.

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.1
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• pp.20-28
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• 1992

The x-ray fluorescence(XRF) is one of the most convenient and widely used techniques for analyzing trace elements in ambient particulate matters. The objects of the study were to estimate the optimum exposure time using the XRF, to investigate the distributions of heavy metal levels in particulate matters, and finally to study seasonal variation for the concentrations of total suspended particulate matters(TSP) and size fractionated particulate matters. The suspended particulate matters had been collected by a cascade impactor having 9 size fragnated stages for 3 years(Dec. 1988 to Nov. 1991) in Kyung Hee University-Suwon Campus. The particulate matters were then collected on each stage by membrane filters. The weight concentrations were determined by the XRF system. Thus, seasonal variations and relationship between concentration and particle size could be investigated. Resulting distribution was bimodal with the coarse and the fine particle groups minimum occurring around 2.1 to 3.3 $\mu$m as an aerodynamic diameter. To determine optimum exposure time of the XRF for various trace inorganic elements, membrane filters and the NIST standard filters were extensively studied. Using a statistical technique, optimum exposure time was estimated for each trace element and overall elements. The time was then determined as 20 seconds for the XRF system. The concentration of TSP was 123.9$\mum/m^3$ on an arithmatic average. The levels of each inorganic metal were Si 2420.0ng/$m^3$, Fe 977.1ng/$m^3$, and so on. The Pb. Zn, and Cu abounded in the fine mode group, while Ca, Fe, Si, Al, and K in the coarse group. Marked seasonal variation of TSP and metal concentrations was observed. The concentration of heavy metals in the fine mode was highest in winter : on the other hand, that in the coarse mode was highest in spring.

• ETRI Journal
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• v.13 no.4
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• pp.80-87
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• 1991

Heavily unintentionally doped n-type InGaP wa grown by LPE technique. Temperature and excitation power dependence of PL measurements were carried out to investigate the first observed 2.107 eV PL peak in $In_0.5$$Ga_0.5$P. Also the unintentionally doped major impurity was found to be sulfur through XRF technique.

• Conservation Science in Museum
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• v.12
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• pp.35-45
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• 2011

To keep relics excavated in the era of the Japanese Colonist's rule in the Korean Peninsula in order, the National Museum of Korea selected some of horse strap pendants (Haengyeob) that were excavated from Seobongchong, Sikrichong and Geumryeongchong, and it investigated conservation and production technique. The horse strap pendants selected were classified into three, that is to say, Oval and fish-tail shape, heart shape and atypical: At the results of microscopic observation, XRF and SEM-EDS analysis, base plate was made of iron, and top plate as well as pattern plate was made of iron, copper and silver. Both Oval and fish-tail shape and heart shape horse strap pendants had horse strap pendants having same production technique and sizes at all of three ancient tombs were made of iron and copper. The gold layer of horse strap pendants except the atypical one having no gold layer were made by amalgam gilding.

• Conservation Science in Museum
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• v.16
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• pp.82-95
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• 2015

Old Monk by Yun Duseo is realized to use silver paper which is made of rarity material. This sudy investigates reason why silver, that is easily discoloration in environmental condition, is susceptible in present. The method was the surface treatment materials and the base fiber through direct observation, optical instruments and XRF analysis. Based on these results, reproducing experiment was conducted to research materials in paper of Old Monk and the surface treatment technique. The results, the paper was treated 'Dochim' with a mineral having polygonal crystals for improving smoothness and density. XRF analysis result showed high calcium content, therefore, the paper was not used silver, it guess pulverized shells of abalone or other types of shellfish. Accordingly, the research was narrowed down to shells with shiny, reflective surfaces which at the same time contain high amounts of calcium. A new experiment was conducted using unprocessed abalone shells. Through the reproducing experiment, shellfish has high possibility as used mineral in paper. Notwithstanding, this experiment was unable to precisely reproduce the smoothness and shine of the original paper. Further research may therefore be needed.

• Journal of Conservation Science
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• v.26 no.1
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• pp.33-41
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• 2010

The archival objects are tangible evidence reflecting public work as forming archives which are administrative, historic, symbolic, cultural and artistic value. They are produced from the various countries so that they have different material and manufacture techniques. However there are difficulties in conservation and management because the material investigation and conservation management system are not established. Therefore this research presents fundamental data for the efficient conservation management by material investigation and condition check metal archival objects. Among the public official presents made of metal, 12 pieces which are discoloration, oxidation, loss or crack are chosen for this research. In order to examine extensive condition of metal archival objects, the condition check card used from the domestic museum and the national museum in Japan are collected and then the new check card is produced. X-ray is used to know the making technique, binding means between different material. Portable-XRF is also used for the chemical composition analysis of metal archival objects, and then classifying respectively according to their material. As a result of condition check, it is possible to investgate the appearance character, deteriorated parts and weak parts of structure. Also P-XRF could find out the composition of metal archival objects which is different from existing condition check card. Therefore the research results can be used as fundamental data for further conservation and management as well as long-term conservation.

• Asian Journal of Atmospheric Environment
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• v.4 no.3
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• pp.189-197
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• 2010

An orchestrated attempt was made to analyze samples of bulk and individual particulate matters (PM) collected at the Gosan ground-based station on the west coast of Jeju, Korea. A two-stage filter pack sampler was operated to collect particles in both large (> $1.2\;{\mu}m$) and small size fractions (< $1.2\;{\mu}m$) between the Asian dust (hereafter called "AD") storm event and non-Asian dust period. Elemental components in bulk and individual particles were determined by PIXE and synchrotron XRF analysis systems, respectively. To assess the transport pathways of air parcels and to determine the spatial distribution of PM, the backward trajectories of the Meteorological Data Explorer (Center for Global Environmental Research, 2010) and the NOAA's HYSPLIT dispersion-trajectory models were applied. In line with general expectations, Si and other crustal elements in large size particles showed considerably higher mass loading on AD days in comparison with non-AD days. Computation of the crustal enrichment factors [(Z/Si)$_{particle}$/(Z/Si)$_{desert}$ sand] of elements in large size particles (> $1.2\;{\mu}m$) allowed us to estimate the source profile and chemical aging of AD particles as well as to classify the soil-origin elements. On the basis of a single particle analysis, individual AD particles are classified into three distinct groups (neutralized mineral particles, S-rich mineral particles, and imperfectly neutralized particles).

• Journal of Conservation Science
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• v.37 no.4
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• pp.402-410
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• 2021

Woolen tapestry curtains possessed by the Seoul Museum of Craft Art were used to hung on the wall or used for carpets in the winter season in the late Joseon dynasty. Since similar artifacts were only used for the curtain as functional aspects, woolen tapestry curtains were a rare case. In this study, scientific analysis on the accessory ornament of woolen tapestry curtains such as components of metal accessories and frame bar were conducted with the microscope, p-XRF, and SEM. Result of frame bar pigments, organic pigments such as ink stick were likely been used in woolen tapestry curtain 1. In woolen tapestry 2, lead red (Minium) was used in the frame bar. The result of metal parts, copper, and zinc were analyzed by p-XRF. This suggests that metal accessories were crafted using brass. Frame bar of woolen tapestry curtain 2 was made of soft pine (Pinus spp.) analyzed with the scanning electron microscope. Artifacts like woolen tapestry curtains are rare in Korea and scientific analysis databases were scarce, so it is important to construct components analysis data of woolen tapestry curtains. It is expected that additional scientific analysis and interpretation on the artifact's crafting technique can be merged with the analytical data gathered in this study to be utilized on the conservation and restoration of not only woolen curtains but curtain artifacts of the late Joseon dynasty in general.

• Conservation Science in Museum
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• v.9
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• pp.85-93
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• 2008

Conservation science team of the National Museum of Korea has conducted conservation treatment for 3 pieces of portraits as a part of project for publishing illustration book of relics of paintings and writings. Among them, portrait scroll of Jo Gyeong is a representative portrait of Seonmoogongsin rank in 17th century of Chosun, which was donated in 1997 and its whole body painted on silk was scrolled. This portrait was in poor state including the silk of portrait got loose from lining paper completely and exfoliation of the pigments. Accordingly before preservation treatment, production technique and the quality of the material lining were surveyed through scientific study(investigation through microscope, XRF, X-ray) and preservation treatment was conducted in order of disassembly, cleaning, removal of lining paper, infiling of the missing parts, lining, finishing.

• Journal of Conservation Science
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• v.27 no.1
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• pp.41-47
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• 2011

If the nondestructive analysis is carried out by using an X-ray Fluorescence Analyzer(XRF) for ingredient analysis with the target of gold plated silverware that plates gold on a silver basis, a singular point showing big difference at the value of weight percent(wt.%) according to the electron orbit of the principal ingredient can be confirmed. The present research made reproduced samples and carried out comparative analysis in order to suggest a basis that can judge whether the technique of gold plated silverware was used in case of remains uneasy to understand with eyes by using this singular point. As a result, the same result as analysis results of actual remains could be seen in specimens manufactured by a mercury amalgam plating method. However, in case of gold and silver alloy specimens, it could be confirmed that the difference according to the electron orbit of the principal ingredients is slight unlike plated specimens. The reason appearing at plated specimens seems to be generated while absorbing XRF beam at plated layers by double structure due to plating instead of single material. Accordingly, if this result appearing at nondestructive analysis is used, it was confirmed that the application of the technique of gold plated silverware can be judged without observing its section.