• Fisheries and Aquatic Sciences
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• v.27 no.9
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• pp.634-643
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• 2024

Silver pompano (Trachinotus blochii) is one of the major commodities of the aquaculture industry in Lampung. Silver pompano hatchery activities that still require natural feed, namely Brachionus sp. Brachionus plicatilis is a filter feeder that does not filter selectively all available feed, so an enrichment process is required so that natural feed reproduces with high nutritional content and is high in fatty acids (eicosapentaenoic acid [EPA] and decosahexaenoic acid [DHA]). This study aims to determine the best survival and growth of silver pompano larvae by feeding B. plicatilis enriched with EPA and DHA fatty acids derived from maggots black soldier fly (BSF). Five-day-old silver pompano larvae with a density of 20 larvae/tank in a 20 × 20 × 20 cm aquarium container. B. plicatilis was fed at a density of 13 ind/mL. Nannochloropsis salina was also given as additional feed at 300-400 cells/mL density. We gave B. plicatilis three times a day (05:00 am, 02:00 pm, and 9.00 pm) for 30 days of cultivation. The experimental treatments were A (no enrichment), B (100 ppm), C (300 ppm), D (500 ppm), and E (700 ppm). The conclusion of this study is the provision of EPA and DHA oil from maggot BSF with different doses of rotifer enrichment has a significant effect on the growth of silver pompano larvae. The results showed that the optimal dose of EPA and DHA oil was 300 ppm or 0.3 mL/L in treatment C with an average absolute length growth of 2.11 cm, and the survival rate reached 75%.

• Economic and Environmental Geology
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• v.26 no.2
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• pp.135-143
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• 1993

Chemical compositions of sphalerites from 25 gold and/or silver deposits in central Korea were obtained with an electron probe microanalyzer. The FeS contents of sphalerites depend generally upon the assemblage of associated iron sulphides (pyrite and/or pyrrhotite) especially. The sphalerites coexisting with pyrrhotite show a narrow range of FeS variation, but the sphalerites associated with pyrite and/or pyrrhotite have the variable and wide range of FeS contents. The sphalerites from Au-dominant deposits, which vary considerably in each deposit, are generally characterized by high CdS content and low MnS content. On the contrary, the sphalerites from Ag-dominant and Au-Ag deposits tend to be characterized by relatively high MnS and very low CdS content. Based upon the mineralogy, fluid inclusions and stable isotope data, the Au-dominant deposits were formed under higher temperature and deeper depth than the Ag-dominant and Au-Ag deposits. The results suggest the possibility that the diverse sources and evolution of ore fluid at the time of ore deposition are responsible for the deposition of Cd and Mn components in sphalerites.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.785-791
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• 2013

This study, in the perspective of universal design, newly suggests UD-WCAG 2013 for the evaluation of job information sites used by the silver generation. Using this, 13 senior clubs run by social welfare corporations chosen by the central and local government for the silver generation job information provision organizations to analyze the compliance status of web accessibility. The web compliance status analysis was done through a self-assessment tool from Korea Agency for Digital Opportunity and Promotion and UD-WCAG 2013. Although both analyses showed that there weren't differences according to region, the general level of compliance was shown as low. In the UD-WCAG 2013's 7 major categories the part about errors was shown providing appropriate solutions, but in the other parts it was shown that the all 13 websites were being run with insufficient consideration of the social and physical characteristics of the silver generation.

• Fashion & Textile Research Journal
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• v.16 no.4
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• pp.635-644
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• 2014

This study provides basic reference data for brassiere wearing conditions, design preferences of new silver women (50s-60s) and development of brassiere products. We compiled and compared 163 pieces of brassiere (considering of 105 domestic general brassieres and 58 foreign silver brassieres) analyzed using SPSS Statistics 21 program. A survey was then conducted on the actual wearing, purchasing conditions, design preferences for 176 females (50s-60s). The result of this study are as follows: First, comparing actual product conditions (domestic general products and foreign silver products), the ratio of full cup in cup height, V-shape type in neckline shape, long type in front-end length, wide type in wing width, U-shape type in shoulder strap form, wide type in shoulder strap width, no-wire brassieres in breast wire type, all-in-one type in shoulder strap separation, back type in closure type appeared higher than other types of brassiere in domestic general product. Second, a study also showed that 60s women's wearing time is lower than 50s women's; however, 60s women expressed a higher figure and preference for the purchasing ratio in the department store, full cup in cup height, short type in length of brassieres, wide type in wing width, U-shape in shoulder strap form, small type in shoulder strap width, back type in closure type and no-wire brassieres than those in their 50s. It was found they prefer fabric with a high natural content, nude tone color without decoration & pattern and camisole brassieres.

• Journal of the Korean Chemical Society
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• v.53 no.5
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• pp.542-546
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• 2009

Recently, silver has been applied to various fields due to antimicrobial property and high conductivity. We manufactured high-performance ophthalmic material containing silver which could protect eye from environmental factors. We mixed $AgNO_3$ with conventional contact lens material. And then we copolymerized at 70 ${^{\circ}C}$ for 40 minutes under water bath, and estimated antimicrobial activity and physical properties. We used solid culture and liquid culture medium for antimicrobial test. The results of contact lens containing silver showed good antibiosis. In case of physical properties, the results showed 32.35%(water content) and 88.34% (visible transmittance) for each. We judged that we made the copolymer with antimicrobial and physical properties which is suitable for conventional contact lens.

• Toxicological Research
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• v.31 no.3
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• pp.307-312
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• 2015

Trans fat is a unsaturated fatty acid with trans configuration and separated double bonds. Analytical methods have been introduced to analyze trans fat content in foods including infrared (IR) spectroscopy, gas chromatography (GC), Fourier transform-infrared (FT-IR) spectroscopy, reverses-phase silver ion high performance liquid chromatography, and silver nitrate thin layer chromatography. Currently, FT-IR spectroscopy and GC are mostly used methods. Trans fat content in 6 vegetable oils were analyzed and processing effects including baking, stir-frying, pan-frying, and frying on the formation of trans fat in corn oil was evaluated by GC. Among tested vegetable oils, corn oil has 0.25 g trans fat/100 g, whereas other oils including rapeseed, soybean, olive, perilla, and sesame oils did not have detectable amount of trans fat content. Among cooking methods, stir-frying increased trans fat in corn oil whereas baking, pan-frying, and frying procedures did not make changes in trans fat content compared to untreated corn oils. However, the trans fat content was so low and food label can be declared as '0' trans based on the regulation of Ministry of Food ad Drug Safety (MFDS) (< 2 g/100 g edible oil).

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.891-899
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• 2008

For the effective use of under-utilized resources, silver-stripe round herring (SSRH), the boiled-dried SSRH was investigated on the food component and sensual characterization. Moisture content and salinity of the boiled-dried SSRH were 27.2% and 7.0%, respectively, which were in the range described in Korean Industrial Standards. In the lipid content of the boiled-dried SSRH, viscera was higher in viscera than muscle. The major fatty acids of the boiled-dried SSRH were 16:0 (23.9%), 18:1n-9 (9.5%), and 22:6n-3 (DHA, 28.5%). The degree of lipid oxidation of the boiled-dried SSRH was similar to that of the boiled-dried anchovy caught in the southern sea. When compared to the boiled-dried anchovies, the boiled-dried SSRH was lower in total content of amino acid, while was higher in calcium and phosphorus contents. The boiled-dried SSRH was higher in taste strength, while was similar in the taste pattern to the boiled-dried anchovies. According to the results of chemical components and sensory evaluation, the boiled-dried SSRH could be substituted for boiled-dried anchovy classified into special grade.

• The Korean Journal of Malacology
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• v.24 no.3
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• pp.243-251
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• 2008

Analyses of UV-Vis spectrum and reflectance are useful tools to identify pearls of which color was naturally made or chemically changed. Contents of some trace elements of pearls by using ED-XRF may give us the information that the pearls were originated from marine shells or freshwater shells, and may give us whether the pearls were chemically treated or not. Three types of chemically untreated pearls, freshwater cultured, Akoya cultured and Tahitian cultured, were treated with silver nitrate. UV-Vis absorbance spectrum of Ag was changed after treatment, and reflectance of pearls was decreased. Absorbance of natural black colored Tahitian cultured pearls at 400, 500 and 700 nm was observed. Natural black colored freshwater cultured pearls showed two characteristic absorption patterns in UV-Vis spectra at 380-400, 480-500 nm. Unlike naturally black colored Tahitian cultured pearls, the absorption spectrum at 700 nm could not be found from black freshwater cultured pearls. Manganese was not detected in the pearls from marine shells, and strontium content of the pearls from marine cultured shells was higher than that from freshwater cultured shells. According to ED-XRF analysis, Ag contents of silver nitrate treated pearls increased as more time passed, because silver ion invaded to nacre layer of the pearls. Since Ag content of the black pearls known as untreated ranged under 0.1%, analysis of Ag content may used to distinguish the black pearls are treated or not in marketplace.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1457-1464
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• 2008

For the effective use of under-utilized resources, silver-stripe round herring (SSRH), the plain-dried SSRH was investigated and compared with boiled-dried SSRH and boiled-dried anchovy on the food component and sensual characterization. Moisture content and salinity of the plain-dried SSRH were 31.9% and 7.6%, respectively. Moisture content of the plain-dried SSRH was higher, while the salinity was lower than those of boiled-dried SSRH and anchovy. According to the results of peroxide value, fatty acid composition, Hunter b value, and browning index, the rancidity was higher in plain-dried SSRH than in boiled-dried SSRH and anchovy. When compared to the boiled-dried SSRH and anchovy, the plain-dried SSRH was higher in calcium and phosphorus contents, while lower in total content of amino acid. According to the results of hot-water soluble-N, trichloroacetic acid-N, free amino acid, and taste value, the taste of plain-dried SSRH was superior to those of the boiled-dried SSRH and anchovy. The results of chemical components and sensory evaluation indicated that the plained-dried SSRH could be substituted for boiled-dried anchovy classified into special grade, if fish odor of SSRH can be improved.

• Journal of Conservation Science
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• v.26 no.2
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• pp.109-120
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• 2010

Four gilded bronze objects and a gilded silver object were examined for elemental diffusion between the gilding layer and the mating matrix. The gilded bronzes consist of three objects from three different historical periods, the Korean Three Kingdoms period, the Koryo and the Choseon periods and one from an unknown period. The gilded silver was from the Koryo period. The amalgam process seems to have been the major technique employed for all of them in gilding. The occurrence of substantial diffusion was observed in all but the anonymous object, particularly in the Choseon artifact where evidence was found that the diffusion phenomenon was intentionally utilized in gilding. The gold content in the gilded bronzes decreases gradually from surface to interior while the copper content increases to the interior, making it difficult to locate the boundary between the gilding layer and the matrix. This gradual change in composition must have resulted from elemental diffusion at elevated temperatures. The oxygen content negligible in the gilding layer precludes the possibility of corrosion being responsible for the varying composition. It is observed that non-uniform diffusion caused variation of colors in the surface of gilded bronzes. The change of colors induced by diffusion, which is always accompanied by the unique surface morphology and chemical compositions, is distinguished from the color change by corrosion. In the gilded silver object, diffusion of mercury was observed along with that of gold and silver.