• Economic and Environmental Geology
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• v.41 no.6
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• pp.773-795
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• 2008

The major import minerals of South Korea are copper ore, lead-zinc ore, iron ore, manganese ore and molybdenum ore. Oversea resources development of South Korea have 92 projects in 14 nations of Asia, 29 projects in 10 nations of America and Europe, and 14 projects in 9 nations of Middle Asia and Africa. But, most projects of them are found in Australia, China, Mongolia and Indonesia. The most projects of the Australia, China and Indonesia are interested in coal and a little projects of them have manganese, iron, lead-zinc, nickel, copper, gold, molybdenum, rare earth elements and uranium. The most projects of the Mongolia are interested in gold and rare earth elements. Representative ore deposits models of metal resources are Orogenic lode deposits, Volcanogenic massive sulphide deposits, Porphyry deposits, Sedimentary exhalative deposits, Mississippi valley type deposits, Iron oxide copper-gold deposits and Magmatic nickel-copper-platinum group element deposits based on global distribution, reverses and grades of their deposits models. If oversea mineral resources will be examined the mineral reserves, mineral mine production and ore deposits models of nations and then survey and investigate of mineral resources, we may be maintained ore body of high grade at survey area and decrease the investment risk.

• Conservation Science in Museum
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• v.23
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• pp.1-16
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• 2020

In this paper, Gilt-bronze Standing Avaolkiteshvara (National Treasure No. 293, M355) excavated at Gyuam-ri in Buyeo was observed with a microscope to identify the production technique applied to it. It was also analyzed with XRF and hard X-ray to identify the composition and the surface treatment techniques and casting method applied. In this statue, Avalokiteshvara is standing upright on a lotus pedestal. The lotus designs on the pedestal and those on the shawl flowing down on both sides of the statue are characteristic of Buddhist statues from the seventh century or later. The use of supports to affix the outer and inner molds and traces of injected cast were observed in the interior of the pedestal. The blisters on the arms and pedestal created during the bronze casting indicate the use of lost-wax casting, which was popularly employed for the production of mid- or small-sized gilt-bronze Buddhist statues in ancient times. The composition analysis identified a copper-tin-lead ternary alloy in the interior of the statue that was conventional used in the sixth and seventh centuries. It is likely that this simple alloy was used to facilitate casting and produce clearer expressions of designs and ornaments on the statue. Mercury (Hg) was detected on the surface of the statue, indicating the use of amalgam-plating with gold (Au) dissolved in mercury. This plating method is a common surface treatment technique used for small gilt-bronze statutes in ancient Korea.

• 보존과학연구
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• s.27
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• pp.129-143
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• 2006

This report is on a scientific investigation of 3 pairs of 금제태환이식 which were excavated from 황남대총 납분. 태환 is a main part of 태환이식 and it could be classified with 4 types in how to produce, especially how many the golden petal was used. In this investigation, they,3 pairs of 금제태환이식 from 황남대총 남분, were in 3 of 4 types and also I could find that this result was not on the technical progress but on the ingredient of metal. Also, In the result of ingredient assay, I could find that although they were in one pair of 태환 one piece was made in gold and silver alloy and the other piece was made in 99.5 percent of pure Ag with gold amalgam plating. And the another pair was getting red from others because of making in 33percent of Ag and 77 percent of gold, high Ag content. And All pairs of 태환 have a small quantity of Copper. As above, although they are one pair they have the difference of how to produce and the difference of volume and ingredient content, it means that these pairs of 태환 from 황남대총 남분 were made in pressure of time. From now on, if we investigate the ingredient and how to produce of 태환이식 in the local comparative analysis, namely natural science method, we can find out the metal art technique and the social aspect of the ancient times as not analogical inference but scientific basis.

• Economic and Environmental Geology
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• v.47 no.6
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• pp.645-655
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• 2014

In order to obtain pure metallic Te from gold concentrate, roasting treatment, hypochlorite leaching, Fe removal and electrolysis experiments were carried out. The contents of Au, Ag and Te from the concentrate sample and roasted sample were much more soluble in the hypochlorite solution than in aqua regia digestion, whereas the metals Pb, Zn, Fe and Cu were easier to leach with the aqua regia than the hypochlorite. With the addition of NaOH in the hypochlorite leaching solution prior to electrolysis, the Fe removal rate achieved was only 96% in the concentrate sample, while it reached 98% in the roasted sample. The results of electrolysis for 240 min, 98% of the metallic copper was recovered from the concentrate sample, while 99% was obtained from the roasted sample due to the removal of S by roasting. The amount of anode slime was also greater in the electrolytic solution with the roasted sample than with the concentrate sample. The results on the anode slime after the magnetic separation process showed the amount of metallic pure native tellurium recovered was greater in the roasted sample than in the concentrate sample.

• Conservation Science in Museum
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• v.15
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• pp.66-77
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• 2014

A gujangbok is a king's silk ceremonial robe embroidered with nine symbols that represent the essential virtues that a king needs to govern his country. The National Museum of Korea currently own a gujangbok worn by King Gojong in the late Joseon Dynasty. The robe is painted with various colors, including red, yellow, blue, green, and gray. μ-XRF and analysis was conducted on the pigments, and it was found that the red color was made from cinnabar, the yellow color was gold and brass, the blue color was a blue organic pigment and white lead, the green color was a synthetic pigment composed of copper and arsenic, and the gray color pigment was silver. Also, the pigments were compared to those used to make the patterns of a queen's ceremonial robe and a front cloth panel, both made around the same time and also owned by the National Museum of Korea. The comparative analysis revealed clear differences and similarities between the various pigments. The resulting data expect to serve as a useful foundation research for future studying of the pigments used by the Joseon royal court in the late nineteenth century.

• Progress in Medical Physics
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• v.22 no.2
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• pp.85-91
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• 2011

The energy spectra for electron beam of medical linear accelerator were calculated using a GEANT4 Medical Linac 2 example code. The incident electron mean energy were 6, 9, 12, 16, 20 MeV. This code was designed to calculate electron beam energy spectra according to material, thickness and location of electron scattering foil affecting electron beam characteristic. Lead, Copper, Aluminum and Gold were used for scattering foil. The energy distribution for electron and photon were analyzed by changing position of scattering foil in the head of linear accelerator. The effect of electron scattering foil on energy spectra which is basic data of simulation for medical linear accelerator were presented. The calculated results would be used in design of medical accelerator head.

• Korean Journal of Environment and Ecology
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• v.21 no.2
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• pp.107-112
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• 2007

This study was carried out to investigate the herpeto-fauna at Hallasan National Park. We conducted a survey at 1100 Resting places, Eoseungsaengak, Donnaeko, Eorimok, Yeongsil, Gwaneumsa and Seongpanak from April, 2006 to January, 2007. A series of four families and 5 species of amphibians and 4 families and 8 species of reptiles were observed. Amphiesma vibakari ruthveni, Takydromus wolteri, Scincella vandenburghi, Coluber spinalis and Hynobius quelpartensis which are rarely appearing inland but they were frequently observed by this survey. Also, we observed Sibynophis chinensis that only inhabits Jeju island with in Korea. Jeju island has both southern and northern boundary lines for amphibians and reptiles. Amphibians and reptiles in Jeju island have a different from those inland and valuable information for biogeograpy due to dissimilar climate and isolation from continental for a long time. It is not certain whether some amphibians and reptiles, Bufo gargarizans, Rana rugosa, R. plancyi, Elaphe rufodorsata and Takydromus amurensis, inhabit Jeju island, as recorded in previous literatures, so the research on current status of them has to be carried out immediately.

• Conservation Science in Museum
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• v.18
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• pp.51-64
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• 2017

The Bracket clock in the collection of the Korean Christian Museum at Soongsil University underwent conservation treatment for a special exhibition. The compositional analysis showed that the body was made of brass plated with gold by fire-gilding(gold amalgam process), while the dial was identified as pure copper coated with enamel. The hands were made of steel. Remnants of adhesive tape on the dial were cleaned, followed by the addition of a protective coating. In order to restore it to a condition as similar to its original form as possible, replacements for missing parts were newly constructed out of brass and were connected to the hands and the dial. The dial was then fixed to the body using an acrylic support. The compositional analysis and conservation treatment have left the clock in stable condition and readily available for exhibitions and future studies.

• Resources Recycling
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• v.26 no.4
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• pp.9-18
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• 2017

Recently, the amount of electronic scrap is rapidly increasing due to the rapid growth of the electronics industry. Among the components of electronic scrap, the printed circuit board(PCB) is an important recycling target which includes common metals, precious metals, and rare metals such as gold, silver, copper, tin, nickel and so on. In Korea, however, PCB recycling technologies are mainly commercialized by some major companies, and other process quantities are not accurately counted. According to present situation, several urban mining companies, research institutes, and universities are conducting research on recovery of valuable metals from PCBs and/or reusing them as raw materials that is different from existing commercialization process developed by major companies. In this study, we analyzed not only current status of collection/disposal process and recycling of waste PCBs in Korea but also the trend of recycling technologies in order to help resource circulation from waste PCBs become more active.

• Conservation Science in Museum
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• v.28
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• pp.109-136
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• 2022

This study analyzes the , one of the three panels of 《Welcoming Banquets for the Governor of Pyeong-an》, a documentary painting of the late Joseon Dynasty, with the aim to identify the coloring materials used in the painting. The painting was first imaged at each wavelength in order to minimize the potential problems in the process of analyzing specific parts. This study applied X-rays to identify ink, gold, and organic and inorganic pigments and used infrared rays to find ink and copper-based pigments. It also applied hyperspectral imaging to distinguish organic pigments from black, blue, and green materials. It also analyzed spots selected for each color to identify the following materials: white lead (white), ink/indigo (black), a combination of red lead and cinnabar (red), pink dye, purple dye, iron oxides (brown), orpiment/dye (yellow), malachite/malachite and yellow dye/indigo (green), azurite/white lead and indigo/indigo (blue), indigo and cochineal (violet), and gold leaf (gold). It is expected that more efficient analysis will be made possible by securing a sufficient library for each wavelength.