• Title/Summary/Keyword: 사금

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Morphology, Mineralogy and Genetic Implication of Placer Gold from the Huongkhe Area, Vietnam (베트남 홍케 지역 사금의 산상과 생성연구)

  • Choi, Sang-Hoon;Choi, Seon-Gyu;Han, Jin-Kyun
    • Economic and Environmental Geology
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    • v.29 no.3
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    • pp.235-246
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    • 1996
  • Placer gold in collected heavy minerals from several localities in Huongkhe area, is consistently very finegrained (${\leq}100$ to $400{\mu}m$). The size and size distribution show somewhat differences at Dongdo and Hoahai : at Dongdo, predominant relatively larger and wide distribution; at Hoahai, characteristic relatively finer and narrow distribution range. The morphology of gold grains is divided into the four groups assumed by the dimension ratio : spherical, subprismoidal, prismoidal, and irregular. The gold grains at Dongdo show wide morphological distribution, whereas, at Hoahai, spherical form is predominant (${\approx}75%$). Three main types of gold are classified based on their chemical composition and mode of occurrence: type I (electrum; fineness=568~931), type II (amalgam; fineness=671~927), and type III (native gold; fineness=923~999). Type I gold contains, relatively high and variable silver contents (${\approx}11$ to 58 atomic % Ag), and has been classified into two subtypes based on their silver contents (type IA, ${\approx}11{\sim}39$ atomic % Ag; type IB, ${\approx}40{\sim}58$ atomic % Ag). However, type I gold would have been generally original compositions of electrum which originated at the provenance deposits. Mercury reacts with gold and silver to form amalgam (type II gold) which has variable Hg contents (1.2~30.5 atomic % Hg). The mercury contents in gold grains at Hoahai (10.9~30.5 atomic % Hg) are higher than those at Dongdo (5.8~21.1 atomic % Hg). The gold grains from the area generally exhibit a high-purity gold (type III) rim. The individual rims on the various grains range from <1 to $80{\mu}m$ in thickness and have silver contents of <10 atomic percent Ag, even though the core compositions range from ${\approx}11$ to 58 atomic percent Ag. The rim of gold most likely is responsible for the commonly cited cases of gold from placer deposits assaying at higher values of fineness than the gold in the corresponding source lode. The gold-rich rim in the Huongkhe area apparently forms by a combination of self-electrorefining and preferential dissolution of silver under oxidizing nature during the weathering and transport process. All data of gold grains in the Huongkhe area suggest that the transport distances and/or time of placer gold at Hoahai are generally farther than those at Dongdo. The mercurian gold bearing provenance deposits at Dongdo and Hoahai would be suggest nearest epithermal gold-silver vein-type.

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무역정보

  • Korea Feed Ingredients Association
    • Feed Journal
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    • v.4 no.11 s.39
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    • pp.46-52
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    • 2006
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Occurrence of Placer Gold Deposits from the Takaoi Area of the Middle Kalimantan, Indonesia (인도네시아 중부 칼리만탄 따까오이 지역 사금광상의 산출상태)

  • Kim In-Joon;Lee Jae-Ho
    • Economic and Environmental Geology
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    • v.39 no.2 s.177
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    • pp.191-212
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    • 2006
  • Placer gold deposits is mainly distributed in the Takaoi area. The alluvium is unconsolidated or semiconsolidated deposit consisting of gravel, sand, and soil beds in ascending order. They unconformably overlies the Carboniferous-Permian schist and Cretaceous granodiorite substratum. Based on detailed facies analysis, the alluvium can be interpreted as a typical fluvial deposits containing gravel and sand beds of channel-fill unit and soil deposit of floodplain. Gold grains are included mainly in the gravel bed and vein quartz is only contained gold among all kinds of gravels. These features indicates that the source rock of the gold grain is vein quartz and gold grains are separated from vein quartz during transport and abrasion. The reserves of gold in this area reach to at least 792 kg.

은행주식 소유제한에 관한 소고

  • Yu, Yun-Ha
    • KDI Journal of Economic Policy
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    • v.23 no.1_2
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    • pp.5-70
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    • 2001
  • The often raised arguments against allowing Chaebol's ownership of banks, that is, 1) the banks may virtually be transformed into private cash vaults of owners, and 2) conflicts of interests may develop and be possibly abused by chaebols, do not hold under ordinary free market circumstances. Only under some special circumstances in which government imposes artificial regulations on banks such as interest rate ceilings, or provides preferential protection like guaranteeing bank's liabilities, the aforementioned worries can be materialized.

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The Effect of the Secondary Spread of COVID-19 on the Willingness to Pay for the Urban Heat Island Reduction Project (COVID-19 2차 확산기가 도시열섬저감 사업의 지불의 사금액에 미치는 영향 -장위동·서교동의 옥상녹화 사업을 중심으로-)

  • Joo, Jin-Ho;Lee, Hyun-Kyung;Kim, Hong-Bae
    • Journal of the Korean Regional Science Association
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    • v.38 no.3
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    • pp.41-49
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    • 2022
  • This paper aimed at understanding the effect of infectious disease conditions on willingness to pay for the green roof implemented to reduce the urban heat island. For this purpose, the willingness to pay for the green roof under infectious disease and non-infectious disease conditions was calculated and comparatively analyzed using the contingent valuation method. As a result, there was a statistically significant difference in the willingness to pay according to the infectious disease condition, and it was confirmed that the willingness to pay for the infectious disease condition was lower than the non-infectious disease condition.

Isolation of an acid-tolerant Leuconostoc mesenteroides LM3 from Kimchi (김치에서 산내성을 가진 Leuconostoc mesenteroides LM3의 분리)

  • 사금희;백상규;윤혜선;강경희;정진국;김일섭;문혜연;김사열;유춘발
    • Journal of Life Science
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    • v.12 no.6
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    • pp.812-820
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    • 2002
  • In order to understand stress response of Leuconostoc mesenteroides against lactic acid, a new Leuconostoc sp. which has acid tolerance was isolated from various Kimchi samples. And it identified as Leuconostoc mesenteroides LM3 by comparing its fatty acid composition with reference strain. Its growth pattern was investigated by adding a given concentration of lactic acid at the lag phase to the stationary phase. In the DeMan, Rogosa, Sharpe (MRS) media containing over 0.4% (final v/v) lactic acid, this strain slowed slowly After exposure of the stationary phase cells to 4% of lactic acid for 60 min, this strain could survive, whereas a reference strain, Leuconostoc mesenteroides KCTC3505, showed no survival. And changes of trehalose concentration, the activity of trehalase and ATPase in the growth of Leuconostoc mesenteroides LM3 after addition of 0.6% (final v/v) lactic acid were investigated : After exposure to lartic acid, trehalose concentration in this strain was increased in comparison with no treatment, but its trehalase activity was not changed. And its ATPase activity was constant, and intracellular pH was almost constant. This result meant Leuconostoc mesenteroides LM3 should have a tolerance against lactic acid. It remains to further study the mechanism of this acid tolerance.

진사탁(陳士鐸)의 장부오행병리(臟腑五行病理)와 잡병오행병리(雜病五行病理) -진사탁적장부오행병리급잡병오행병리(陳士鐸的臟腑五行病理及雜病五行病理)-

  • Lee, Byeong-Jik;Yun, Chang-Yeol
    • Journal of Korean Medical classics
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    • v.18 no.1 s.28
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    • pp.121-136
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    • 2005
  • 통적연구진사탁적장부오행병리급잡병오행병리적운용연구(通適硏究陳士鐸的臟腑五行病理及雜病五行病理的運用硏究), 득출이하결론(得出以下結論) : 진사탁인위진관폐금극간목(陳士鐸認爲盡管肺金克肝木), 단시약간중지화왕성(但是若肝中之火旺盛), 칙폐무법극간차치간화극토사장토수손(則肺無法克肝且致肝火克土使將土受損), 종이사비위무법생금이치폐금갱가쇠약(從而使脾胃無法生金而致肺金更加衰弱), 폐불능생수이수무법극화(肺不能生水而水無法克火), 도치상중하삼초지화균과왕(導致上中下三焦之火均過旺). 타인위간희소설(他認爲肝喜疏泄), 당약울체회사기극비위(?若鬱滯會使其克脾胃), 비위수극칙토극수(脾胃受克則土克水), 이신수손무법생목(而腎受損無法生木), 사간울갱심심화무법화생(使肝鬱更甚心火無法化生), 차폐역무법극목(且肺亦無法克木). 차시(此時), 응이해울법내치료(應以解鬱法來治療). 타인위수연토극수(他認爲雖然土克水), 단시토생수여금생수적관계갱위밀절(但是土生水與金生水的關係更爲密切), 이폐여신우위밀절차유상생적관계(而肺與腎尤爲密切且有相生的關係), 고지유신중지수충족(故只有腎中之水充足), 방가수화기제(方可水火旣濟). 타인위심위군화시유형지화(他認爲心爲君火是有形之火), 가용수극지(可用水克之), 이신중지화위무형지화(而腎中之火爲無形之火), 차가양수(且可養水). 타인위명문지화가생비토(他認爲命門之火可生脾土), 단약과왕칙무법생비토반이극토(但若過旺則無法生脾土反而克土). 차시(此時), 여기직접보신수(與其直接補腎水), 불여보폐금사금생수(不如補肺金使金生水), 차위보수적근본지법(此爲補水的根本之法). 진사탁재설명오장적병리기제시인위(陳士鐸在說明五臟的病理機制時認爲), 오장지화과왕칙회사상생관계변성상극관계(五臟之火過旺則會使相生關係變成相克關係), 이적의적화칙능유지정상적상생관계(而適宜的火則能維持正常的相生關係), 차즉사화불족역가유지상생(且卽使火不足亦可維持相生). 진사탁인위제료외감(陳士鐸認爲除了外感), 기호소유적잡병도이장부오행적상생(幾乎所有的雜病都以臟腑五行的相生), 상극(相克), 이급상관적관계위중심내설명료기병리(以及相關的關係爲中心來說明了其病理), 저일점성위료기학술사상적중요특점(這一點成爲了其學術思想的重要特點).

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