• Conservation Science in Museum
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• v.4
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• pp.57-61
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• 2003

From the stupa of Sujongsa-Temple, located in Yangpyeong, Gyeonggi-do province, was excavated a celadon jar with lid, a gilt-bronze nine-storied miniature pagoda and a silver-plate hexagonal miniature shrine, etc. Among them, the gilt-bronze miniature pagoda has been known as a gilt-bronze product since most of its surface has copper tint and the base part has bronze corrosion. Its formal title registered on the Cultural Properties Administration also begins with "a gilt-bronze". However, it was supposed to be a gold product in many aspects: the color and status of the surface, degree of the bronze corrosion creation and the metal thread joining the wind bell. So the necessity to prove its material by a scientific analysis was raised. We examined it with nondestructive method. The results were traces of open-working on many parts of the surface, but no traces of gilding. Moreover, as we perform an XRF analysis, the main component were gold and silver(16%) and some impurities such as copper and iron were found. Therefore, it could be inferred that this miniature pagoda is a gold product.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.891-892
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• 2006

An obstacle is an element for power to small and slim the existing portable communication set. Developed Inductor for Chip-type electric power in needs to solve this. Stack applied Process, and used gap of a magnetic path, and made a height of an element to 1.0T or below, and this development commodity did product for saturation prevention to materials of silver. Saturation current characteristic of Chip-type inductor was low compare with winding-type inductors, but bulk against performance were had superior excellence. Chip-type inductor can raise performance per unit volume compared with the existing inductors at these papers. Therefore, acceleration can get growth of small and slim of a mobile product done, and expect.

• Fashion & Textile Research Journal
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• v.17 no.3
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• pp.429-439
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• 2015

This study develops a new brassiere for new silver women. A new brassiere design was developed for the silver generation based on apreliminary survey; subsequently, a wire and no-wire type of brassier were developed after a second fitting evaluation. The results were as follows. First, in terms of brassiere design, the cup shape was designed as mold type full cup, shoulder straps were designed as camisole type with cups, bias tape was designed for body correction in the side line and mash tape was designed for easy movement below the cups. On the other side ofthe cup shape was a pocketdesigned on a support pad forthe wire type and a support panel to serve as a wire in the no-wire type brassiere. Second, brassiere patterns were designed by referencing the educational H pattern. Thetotal length was elongated by 5cmto reduce pressure when wearing a brassiere and the height of the front center increased by 8cm for the stability of the front center of the brassiere. In addition, the side line was moved back by 3cm and the width of the brassiere wings was designed widely at 10.5cm. Third, a wearing test was conducted for the wire type and the no-wire type brassiere with comparison products, using a 7-point Likert scale. Appearance results and movement tests for the wire and no-wire type showed a higher score than comparison products.

• Economic and Environmental Geology
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• v.19 no.4
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• pp.243-264
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• 1986

This work is a metallogeny on gold-silver deposits in South Korea based on the close examination of the author's own data and a broad review of existing literature available. The metallogenic epochs in Korea are temporarily connected with the history of tectonism and igneous activities, and are identified as the Precambrian, Paleozoic, Jurassic to early Cretaceous, late Cretaceous to early Tertiary, and Quaternary epochs, whereas the metallogenic provinces are spatially associated with some of the felsic to intermediate igneous rocks, lacking mineralization related to basic and ultrabasic rocks. The metallogeny on the gold-silver deposits is mostly related to the granitic rocks intrusives. Epigenetic gold-silver mineralization in South Korea ranges in metallogenic epochs from Precambrian through Triassic, Jurassic and Cretaceous to Eocene (?), in genetic types from hypothermal through mesothermal and epithermal quartz-sulfide veins to volcanogenic stockworks, with some disseminated types. Reporting on metallic association from gold without silver, gold-silver, silver-gold, silver without gold, and gold or silver as a by-product from other metallic ores. The most representative genetic types and metal associations of gold-silver deposits are hydrothermal quartz veins associated with the Daebo and Bulgugsa granitic magmatism. The most closely associated paragenetic metallic minerals in gold-silver hydrothermal quartz-sulfide vein type deposits are: copper, lead, zinc, pyrite and arsenopyrite. More than 560 gold-silver mines are plotted in the distribution map grouped within the 10 different metallogenic provinces of South Korea. Specific mineralizations with related mineral association in both sulfides and gangues observed selected from 18 Korean and 8 Japanese Au-Ag deposits. The 7 selected individual gold-silver mines representing specific mineralization types are described in this report.

• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.140-146
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• 2012

The commercial product "pyto-patch" prepared as nano sized silver particle less than 5 nm, has effective antifungal activity against Collectotrichum gloeosporioides, Botrytis cinerea, Sclerotinia sclerotiorum in vitro. As a fungal growth inhibiton mechanism, it can reduce spore germination rate and mycelial growth. As s promising fungicide, Phyto-patch can control anthracnose effectively. The spore of C. gloeosporioides dipped in 5 ppm phyto-patch dilute suppressed germination rate to 13.2%, and mycelial growth stopped for 15 days at 10 ppm. The spore postinoculated on 10 ppm phyto-path smeared PDA surface could not germinate for 3 days and prohibit pathogen infection effectively. In field test, the anthracnose development of 4 ppm phyto-patch treated plot was less than 7% after 21 days compaired to 40% of it in untreated plot. In heavy rainfall season, pepper anthracnose effectivly contrrolled by regular 10 ppm phytopatch spraying every 7 days. The diseased pepper fruit decreased to 5.8% compaired to 94.6% in untreated plot. During drying period, the diseased pepper fruit havested in phyto-patch treated plot was 24.2%, but pepper fruit havested in untreated plot destroyed to 100% within 3 days. The nano silver particle coated on multching textile prevented late blight of pepper effectively and disease occurance delayed about month.

• Korean Journal of Heritage: History & Science
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• v.49 no.2
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• pp.172-189
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• 2016

In this research, literature research on the Odong material, mixture ratio, casting method and casting facility was conducted on contemporary documents, such as Cheongong Geamul. Also, a long sword was produced using the Odong inlay technique. The sword reproduction steps were as follows; Odong alloying, silver soldering alloying, Odong plate and Silver plate production, hilt and sheath production, metal frame and decorative elements, such as a Dugup (metal frame), production, Odong inlay assembly and final assembly. For the Odong alloy production, the mixture ratio of the true Odong, which has copper and gold ratio of 20:1, was used. This is traditional ratio for high quality product according to $17^{th}$ century metallurgy instruction manual. The silver soldering alloy was produced with silver and brass(Cu 7 : Zn 3) ratio of 5:1 for inlay purpose and 5:2 ratio for simple welding purpose. The true Odong alloy laminated with silver plate was used to produce hilt and sheath. The alloy went through annealing and forging steps to make it into 0.6 mm thick plate and its backing layer, which is a silver plate, had the matching thickness. After the two plates were adhered, the laminated plate went through annealing, forging, engraving, silver inlaying, shaping, silver welding, finishing and polishing steps. During the Odong colouring process, its red surface turns black by induced corrosion and different hues can be achieved depending on its quality. To accomplish the silver inlay Odong techniques, a Hanji saturated with thirty day old urine is wrapped around a hilt and sheath material, then it is left at warm room temperature for two to three hours. The Odong's surface will turn black when silver inlay remains unchanged. Various scientific analysis were conducted to study composition of recreated Odong panel, silver soldering, silver plate and the colouring agent on Odong's surface. The recreated Odong had average out at Cu 95.57 wt% Au 4.16wt% and Cu 98.04 wt% Au 1.95wt%, when documented ratio in the old record is Cu 95wt% and Au 5wt%. The recreated Odong was prone to surface breakage during manufacturing process unlike material made with composition ratio written in the old record. On the silver plate of the silver and Odong laminate, 100wt% Ag was detected and between the two layers Cu, Ag and Au were detected. This proves that the adhesion between the two layers was successfully achieved. The silver soldering had varied composition of Ag depending on the location. This shows uneven composition of the silver welding. A large quantities of S, that was not initially present, was detected on the surface of the black Odong. This indicates that presence of S has influence on Odong colour. Additional study on the chromaticity, additional chemical compounds and its restoration are needed for the further understanding of the origin of Odong colour. The result of Odong alloy testing and recreation, Odong silver inlay long sword production, scientific analysis of the Odong black colouring agent will form an important foundation of knowledge for conservation of Odong artifact.

• Journal of Soil and Groundwater Environment
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• v.20 no.6
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• pp.85-94
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• 2015

RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) is the most important explosive contaminant, both in concentration and in frequency, at military shooting ranges in which green technologies such as phytoremediation or constructed wetlands are the best option for mitigation of explosive compounds discharge to the environment. A study was conducted with two identical lab-scale plug flow constructed wetlands planted with Amur silver grass to treat water artificially contaminated with 40 mg/L of toxic explosive compound, RDX. The reactor was inoculated with or without RDX degrading mixed culture to evaluate plant-microorganism interactions in RDX removal, transformation products distribution, and kinetic constants. RDX and its metabolites in water, plant, and sediment were analyzed by HPLC to determine mass balance and kinetic constants. After 30 days of operation, the reactor reached steady-state at which more than 99% of RDX was removed with or without the mixed culture inoculation. The major transformation product was TNX (Trinitroso-RDX) that comprised approximately 50% in the mass balance of both reactors. It was also the major compound in the plant root and shoot system. Acute toxicity analysis of the water samples showed more than 30% of toxicity reduction in the effluent than that of influent containing 40 mg/L of RDX. In the Amur silver grass mesocosm seeded with the mixed culture, the specific RDX removal rate, that is 1st order removal rate normalized to plant fresh weight, was estimated to be 0.84 kg⁻¹ day⁻¹ which is 16.7% higher than that in the planted only mesocosm. Therefore, the results of this study proved that Amur silver grass is an effective plant for RDX removal in constructed wetlands and the efficiency can be increased even more when applied with RDX degrading microbial consortia.

• Journal of Powder Materials
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• v.15 no.3
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• pp.221-226
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• 2008

Silver coated copper composite powders were prepared by electroless plating method by controlling the activation and deposition process variables such as feeding rate of silver ions solution, concentration of reductant and molar ratio of activation solution $(NH_4OH/(NH_4)_2SO_4)$ at room temperature. The characteristics of the product were verified by using a scanning electron microscopy (SEM), X-ray diffraction (XRD) and atomic absorption (A.A.). It is noted that completely cleansing the copper oxide layers and protecting the copper particles surface from hydrolysis were important to obtain high quality Ag-Cu composite powders. The optimum conditions of Ag-Cu composite powder synthesis were $NH_4OH/(NH_4)_2SO_4$ molar ratio 4, concentration of reductant 15g/l and feeding rate of silver ions solution 2 ml/min.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.6
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• pp.529-537
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• 1993

Several methods were examined for purification of docosahexaenoic acid (DHA, 22:6n-3) from skipjack Euthynnus pelamis orbital tissue oil, a marine by-product, and a modified method for isolation of a high purity DHA was proposed. Skipjack orbital tissue contained $55.4\%$ of total lipid(TL), and DHA accounted for $23.7\%$ of the TL. Application of low-temperature crystallization and urea inclusion compound methods to the orbital fatty acid mixture resulted in increases of DHA concentrations to approximately $46\%\;and\;61\%$, respectively. These methods were suitable for large production of DHA with relative low purity because of the simple purification procedure. DHA of approximately $74\%$ in purity was obtained by silver nitrate aqueous solution method, but the method gave a very low recovery($<10\%$). Silver nitrate-impregnated silica column chromatography was suitable for purification of a high purity DHA(purity, $>98\%$ and recovery, $>90\%$) A modified method, silver nitrate-impregnated silica column chromatography combined with low-temperature crystallization(two step purication method) was proposed as the most effective method to obtain DHA with high purity($99.9\%$) from the skipjack orbital oil.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.722-726
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• 2008

Silica microsphere is a world leading innovative material used in adsorbent packing materials in HPLC technology. The application of microsphere lies in the ability to the surface modification of silica with the special materials such as polymers, metals and bio-active materials. Collagen is a major structural protein of connective tissues and has a good biocompatibility. In this study, we prepared the purified silica porous microsphere, having micro diameters in the range of a pore volume at least 50% by the aggregation procedure of colloidal silica with the polymerization method (PICA). The microspheres were modified by collagen hydrogel to improve the biocompatible properties for biomedical product. The silica/collagen microsphere composite doped with silver nanoparticles was prepared and investigated the capabilities of biomaterial application through the evaluation of the structure characteristics of the microsphere composit.