• 제목/요약/키워드: MoMA

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patterns and crust - mantle interactio

  • Du, Y.
    • Proceedings of the KSEEG Conference
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    • 2000.04a
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    • pp.110-110
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    • 2000
  • Temporal and spatial distribution patterns of the magmatic rocks and associated ore deposits in the Mesozoic magmatic - metallogenic belt along the Yangtz River, Anhui Province are used to determine and discuss the crust - mantle interaction processes. The magmatic rocks are Cu - Au mineralized high - K calc - alkalic intermediate ¬acidic (CAK) and Fe - Cu mineralized high - Na alkalic - calc intermediate - basic intrusive rocks (FCN) in the central part of the belt and grade to Cu - Mo - Pb - Zn - Ag mineralized calc - alkalic granitoids (CMG) and A - type granites (AG) in the southern and northern parts of the belt. Samples from the CAK and CMG yield Rb - Sr isochron ages of 137 - 140Ma with $(^{87}Sr/^{86}Sr)_{o}$ = 0.7060 - 0.7101, while those from the FCN and AG yield the ages of 120 - 129Ma with $(^{87}Sr/^{86}Sr)_{o}$ = 0.7047 - 0.7077. The Sr isotope ratios, CriTh ratios 0.4 - 3.1), Eu/Eu* ratios < 0.79 - 1.05) and initial epsilon (Nd) values (-16.6 - -6.3) for the CAK and CMG are consistent with magma derivation from old metamorphic basement rocks rich in metallogenic elements through a two - stage process of mantle - derived magma underplating caused by primary lithosphere extension and subsequent partial melting. On the basis of Sr isotope data, CriTh ratios (3.4 - 13.8), Eu/Eu* ratios (0.86 - 1.13) and initial epsilon (Nd) values (-7.7 - +1.4), the FCN and AG are considered to be formed through syntexis with material input from the mantle that resulted from further lithosphere extension followed by mantle - derived magma underplating on a large scale.

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Timing of Metamorphism of the Metavoclanics Within the Gyemyeongsan Formation (계명산층 변성화산암의 변성시기)

  • Kim, Myoung-Jung;Park, Kye-Hun;Yi, Keewook;Koh, Sang Mo
    • The Journal of the Petrological Society of Korea
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    • v.22 no.4
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    • pp.291-298
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    • 2013
  • We identified well developed overgrowth rims from several zircon grains separated from the Gyemyeongsan metavolcanics of the Okcheon Metamorphic Belt. Such overgrowth rims reveal generally quite low Th/U ratios indicating formation during the metamorphism. We were able to conduct SHRIMP U-Pb spot analyses from the relatively wide overgrowth rims and determined a concordia age of $259.7{\pm}3.3Ma$ (n=8, $2{\sigma}$), which indicates timing of the regional metamorphism occurred in the Gyemyeongsan Formation.

General Remarks of Geneses of Tungsten Ore Deposits Based on Tungsten Deposits of China (중국의 중석광상을 근거로한 중석광상 성인 총론)

  • Moon, Kun Joo
    • Economic and Environmental Geology
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    • v.28 no.3
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    • pp.287-303
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    • 1995
  • Tungsten ore deposits in China show clearly their relationship between granitoids and orebodies. All kinds of different tungsten ore deposits, having the largest ore reserves in the world, occur in China. Major tungsten deposits in 1950'years were locally confined in three provinces such as Jiangxi, Hunan and Guangdong. However, the major tungsten ore deposits are replaced by new tungsten deposits such as Sandahozhuang, Xingluokeng, Shizhuan and Daminghsan deposit which may be larger than the previous major deposits. Tungsten ore deposits of China exhibit obviously the granitoid was the ore-bringer to form tungsten ore deposits. The wolframite-bearing quarz veins in China indicate that tungsten mineralization took place by crystallization of wolframite preferentially unless $Ca^{{+}{+}}$ was introduced from outside into the magma-origin-fluid, since it is understood that the scheelite in the Sangdong ore deposit was preferentially precipitated, because of chemical affinity, from the tungsten fluid in which Fe and Ca ions were as sufficient as to form magnetite, wolframite and scheelite. Tungsten deposits in the world are divided into two systems; W-Mo-Sn system and W-Mo system. Most of tungsten deposits in China dated to about 196-116 Ma belong to the W-Mo-Sn system, while late Cretaceous tungsten deposits such as the Sangdong deposit in Korea belongs to the W-Mo system. The genetic order of tin-tungsten-molybdenum mineralization observed in the Moping tungsten mine in China and the Sangdong in Korea may be attributed to volatile pressures in the same magma chamber. It is assumed from ages of tungsten mineralizations that ore elements such as tin, tungsten and molybdenum might be generated periodically by nuclear fission and fusion in a part of the mantle and the element generated was introduced into the magma chamber. The periodical generation of elements had determined association, depletion and enrichment of tin and molybdenum in tungsten mineralization and it results in little association of cassiterite in tungsten deposit of late Cretaceous ages. Different mechanism of emplacement of the ore-bearing magma has brought various genetic types of tungsten deposits as shown in China and the world.

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Production of Ni-Cr Metal Powder by Selective Laser Melting for Dentistry to Observation of Characteristics (치과 SLM용 Ni-Cr 금속분말 특성 관찰)

  • Hong, Minho
    • Journal of Technologic Dentistry
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    • v.37 no.1
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    • pp.23-29
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    • 2015
  • Purpose: The selective laser melting (SLM) process for dentistry, which is one of the additive manufacturing technologies (AM) allows for rapid production of a three-dimensional model with complex shape by directly melting metal powder. This process generates detailed items of a three-dimensional model shape through consolidation of a thin powder layer by utilizing both selective melting and laser beam simultaneously. In regard to SLM process, Fe-base powder, Ti-6AI-4V powder, AI-base powder, etc. have been researched. It is believed that the aforementioned technologies will be widely utilized in manufacturing metal parts using metal powder of raw material. This study chose Ni-Cr-Mo metal powder in order to manufacture metal powder materials that would be used in the selective laser melting for dentistry. Methods: This study manufactured metal powder using mechanical alloying technique (MA) among those metal powder manufacturing techniques. Moreover, this study aimed to utilize the metal powder manufactured after observing the characteristics of powder as preliminary data of Ni-Cr-Mo metal powder. This study could obtain the following conclusions within the experimental limitations. Results: As a result of mechanically alloying Ni-Cr-Mo powder over time, its mean particle size was $66.93{\mu}m$ $54.4{\mu}m$ and $45.39{\mu}m$ at 10h, 20h and 30h, respectively. The gtain form of metal powder by mechanical alloying technique was a sponge-like shape of irregular plate; however, the gtain form manufactured by high-pressure water aromization process had the following three types: globular type, chain type and oval type. Conclusion: This study found $37.65{\mu}m$ as the mean particle size of Ni-Cr-Mo metal powder, which was manufactured using water atomization technique under the following conditions: water atomization flux of 300 liter/min, hydraulic pressure of $400kgf/cm^2$ and injection angle of $45^{\circ}$. This study confirmed that the grain form of powder (solid particle form) would vary depending on the manufacturing process.

Effects of Post-harvest Storage Duration and Variety on Nutrient Digestibility and Energy Content Wheat in Finishing Pigs

  • Guo, P.P.;Li, P.L.;Li, Z.C.;Stein, H.H.;Liu, L.;Xia, T.;Yang, Y.Y.;Ma, Y.X.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.10
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    • pp.1488-1495
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    • 2015
  • This study was conducted to investigate the effects of post-harvest storage duration and wheat variety on the digestibility and energy content of new season wheat fed to finishing pigs. Two wheat varieties (Shi and Zhong) were harvested in 2013 and stored in the warehouse of the Fengning Pig Experimental Base at China Agricultural University for 3, 6, 9, or 12 mo. For each storage period, 12 barrows were placed in metabolism crates and allotted to diets containing 1 of the 2 wheat varieties in a randomized complete block design. The experimental diets contained 97.34% wheat and 2.66% of a vitamin and trace mineral premix. With an extension of storage duration from 3 mo to 12 mo, the gross energy (GE) and crude protein (CP) of the wheat decreased by 2.0% and 12.01%, respectively, while the concentration of neutral detergent fiber (NDF), acid detergent fiber (ADF) and starch content increased by 30.26%, 19.08%, and 2.46%, respectively. Total non-starch polysaccharide, total arabinose, total xylose and total mannose contents decreased by 46.27%, 45.80%, 41.71%, and 75.66%, respectively. However, there were no significant differences in the chemical composition between the two wheat varieties with the exception of ADF which was approximately 13.37% lower in Shi. With an extension of storage duration from 3 mo to 12 mo, the digestible energy (DE), metabolizable energy (ME) content and the apparent total tract digestibility of GE, CP, dry matter, organic matter, ether extract, ADF and metabolizability of energy in wheat decreased linearly (p<0.01) by 5.74%, 7.60%, 3.75%, 3.88%, 3.50%, 2.47%, 26.22%, 27.62%, and 3.94%, respectively. But the digestibility of NDF changed quadratically (p<0.01). There was an interaction between wheat variety and storage time for CP digestibility (p<0.05), such that the CP digestibility of variety Zhong was stable during 9 mo of storage, while the CP digestibility of variety Shi decreased (p<0.05). In conclusion, the GE, DE, and ME of wheat was stable during the first 3 to 6 mo of post-harvest storage, and decreased during the following 6 to 12 mo of storage under the conditions of this study.

Geology and Mineralization of East Africa Rift System (동아프리카 열곡대의 지질 및 광화작용)

  • Koh, Sang-Mo;Lee, Gilljae;Kim, Eui-Jun;Ryoo, Chung-Ryul
    • Journal of the Mineralogical Society of Korea
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    • v.26 no.4
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    • pp.331-342
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    • 2013
  • 동아프리카 열곡대는 아라비아반도와 아프리카 북동부의 경계에서 부채꼴 형태로 남쪽으로 뻗은 대단층 함몰지구대이다. 아프리카 판 내부에 발달한 열곡대의 폭은 35~60 km이며 연장은 약 4,000km로 알려져 있다. 열곡대는 에티오피아에서 남서방향으로 발달하다 에티오피아 남부에서 동, 서 및 남서 열곡대로 나누어진다. 이 열곡대는 제3기초 올리고세(30~35 Ma)부터 에티오피아 북부 아파르 침강대를 중심으로 주 에티오피아 열곡대가 형성되고, 남쪽으로 확장되면서 마이오세에 활성화된다. 서부 열곡대는 동아프리카대지의 가장자리와 빅토리아 호의 서편을 따라 발달하며, 고각의 정단층에 의해 특징되는 전형적인 반지구대이다. 동부 열곡대(주 에티오피아 열곡대와 케냐 열곡대)는 30 Ma 전 화산활동과 지구조활동이 시작되었으나, 서부 열곡대는 Albert 호 북부에서 12 Ma 전에, Tanganyika 열곡에서는 7 Ma 전부터 시작되었다. 서부 열곡대의 남서 방향으로 분기된 남서 열곡대는 DR-콩고 남부와 잠비아의 Tanganyika 호에서부터 남서 방향으로 확장되어 보츠와나 Okavango 열곡대와 연결된다. 주 에티오피아 열곡대(MER)의 화산암류와 관련 퇴적암류는 지열, 소다회, 포타쉬(K), 천열수 금, 벤토나이트, 유황 및 부석자원으로 중요한 관련암으로 역할을 한다. 열곡관련 대표적인 광상으로는 Afar 열곡대에 분포하는 Danakhil K-광상과 Megenta 및 Blackrock 천열수 금광상이다. Danakhil K-광상은 제4기 화산활동과 높은 지열류에 의해 열곡대 내 분포하던 소금 선상지(salt fan)에서 증발작용에 의해 형성된 증발형 K-광상으로서 총 자원량은 약 12.6억톤으로 평가되었다. 이 광상에서는 4종의 K-광물인 실바이트, 카날라이트, 포리하라이트, 카이나이트가 산출한다. 아파르 침강대 내 분포하는 대표적인 천열수 금광상은 텐다호 지구대에 위치하는 Megenta 및 Blackrock 광상이다. 제4기에 EMR에서 산성의 과알칼리 화산활동에 의해 열수활동이 초래되어 현재까지도 활동하여 지열대가 형성되고, 저유황형금 광상들이 형성되었다. Megenta 저유황형 금 광상은 2009년 발견되었으며, 현재 영국의 Startex International사에 의해 탐사가 진행 중이다. 지금까지의 탐사 결과 옥수질 규화 변질암 분포지에서 5개의 광체가 분포하며, 그중 Hyena 광체에서는 규화 변질된 열수각력암에서 최고 16.75 g/t의 금 품위가 보고되었다. 동아프리카 열곡대의 서편인 부룬디에 분포하는 Gakara REE 광상은 카보너타이트 유형의 REE 광상이다. 이 광상은 $400km^2$ 면적 내 수 cm부터 수 m까지의 폭을 가지는 맥상 또는 망상세맥상의 광체를 형성한다. 주로 조립의 바스트너사이트와 모나자이트로 구성된다. 바스트너사이트의 형성시기는 $587{\pm}4Ma$인 신원생대로 알려져 있으며, 이 지역에 분포하는 카보너타이트와 알칼리암들이 신원생대에서 신생대까지의 광범위한 연대를 보이는 것은 동일한 구조선을 따라서 일어나는 반복되는 열곡활동으로 해석된다. 또한 REE, U, 인회석 자원의 관련암체로 생각되는 알카리 조면암(네펠린-조면암 포함)과 카보너타이트는 동아프리카 열곡대의 남동부 끝자락인 말라위와 모잠비크에 우세하게 분포한다.

A Study on The Principles and Philosophical Basis of 'Sa Sang Medicine' (사상의학(四象醫學)의 원리(原理)와 철학적(哲學的) 배경(背景)에 대(對)한 고찰(考察))

  • Song, Jeong-Mo
    • Journal of Sasang Constitutional Medicine
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    • v.4 no.1
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    • pp.5-29
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    • 1992
  • In this study, the author researched the process in which the philosophical basis of 'Sa Sang Medicine (四象醫學)' and its methodology build up the principles of Sa Sang Medicine, and then, examined how the principles were applied to the theoretical system of Sa Sang Medicine. The conclusion would be summarized as follows. 1. 'Nae Kyung Medicine (內經醫學)' was developed under the concept that the cosmos's order and its moving rule could be directly applied to that of human body, which corresponded to the 'Theory of Hwang-No (黃老之學)'. On the contrary, Sa Sang Medicine is a thoroughly human-oriented theory formed in the Confucianism system. 2. Lee Jae-Ma's Substantialism can be briefed into 'Mind 心' (Tae Keuk 太極), 'Mind-Body 心身' (Yang Eui 兩儀) and 'Activity-Mind-Body-Matter 事心身物' (Sa Sang 四象), which respectively represents one-elemented substance, two-elemented substance and four-elemented substance. Especially, Sa Sang was used as a basic framework in which he recognized all the objects and phenomena. So, most critical significance of his substantialism consists in the intention of Sa Sang type classifying. 3. By the method of Sa Sang type classifying, Lee Jae-Ma not only redefined the main concepts of confucianism and developed a unique philosophy of his own, but also, in the field of medical science, resystemized and re-explained the structure and function of human body. 4. From the recognition that Activity-Mind-body-Matter (Sa Sang) are four different existence forms of energy 氣 (or four variation types of energy), Yi Jae-Ma thinks that the viscera of human body have a vertical structure of 'four parts 四焦' (upper, mid-upper, mid-lower and lower parts) and its physiological function is operated by the rising and falling action of four energy presentations (sorrow 哀, anger 怒, joy 喜 and pleasure 樂). 5. In "Gyuk Chi Go 格致藁", Lee Jae-Ma understood the concept of joy, anger, sorrow and pleasure on the basis of nature-emotion theory 性情論 from the philosophical viewpoint. But, from the medical viewpoint of "Dong Eui Su Se Bo Won 東醫壽世保元", he understood them on the basis of vital energy theory. That is, sorrow, anger, joy and pleasure are expression of advance or reverse of nature vital-energy 性氣 and emotion vital-energy 情氣. 6. The rising and falling action principle of four energy presentations (sorrow, anger, joy and pleasure) which produces and helps each other is an identical principles of Sa Sang Medicine, distinguished from the Oh-Haeng 五行 circulating principle in Nae Kyung Medicine. Through this principle, Lee Jae-Ma explained the viscera physiology of human body, pathology & diagnosis and pharmacology.

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A Study on the Textile Terminologies in Kei Lim yu Sa(鷄林類事) I (鷄林類事의 織物關聯用語 硏究 I)

  • 김진구
    • The Research Journal of the Costume Culture
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    • v.7 no.2
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    • pp.211-219
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    • 1999
  • The purpose of this study was to trace and identify termilogies recorded im kei lim yu sa. ma(麻), kyun(絹), po(布), je(苧), and je-po(苧布) were included in this study. For the analysis of this research comparative analytical methods was employed. Some significant findings and results of this study can be summarized as follows : 1. Text : hemp is called san(麻曰三). The word san of Koryo was derived from Indian sann, san, sana, sunn, 2. Text : Kyun is called jyi or kib(絹曰及). The word jyi(及) of Koryo was from jyi or kib() of Silla. 3. Text : Hemp cloth is called bey(bei), pey(pei), bai(布曰背). Be (베) has two meanings of hemp cloth and cloth in Korean. In the text it is interpreted as hemp cloth. 4. Text : Ramie or China grass is called mar, maw, mao, mu (毛). (苧曰毛). It is considered that the word mau(mo in Korean) (毛) in text is correct and word mau(毛) meaning China grass of Koryho is derived from mah or mak that is an old Egyptian name for flax or linen. The word mau(mo) (毛) of Koryo seems to be a transliteration of mah(or mak) in Korean or a variety of it. 5. Raime cloth or China grass cloth is clalled mau shy (苧布曰毛施). Silmar words to mau shy(毛施) of Koryo were found in Chinese, Manchurian and japanese as well as in Ancient Hebrew.

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Selective Epoxidation and Reduction of Rigid Cyclic ${\alpha},{\beta}$-Unsaturated Carbonyl Compounds (환상 ${\alpha},{\beta}$-불포화 카르보닐 화합물의 선택적 에폭시화 및 환원)

  • Ma, Eun-Sook
    • YAKHAK HOEJI
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    • v.49 no.6
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    • pp.443-448
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    • 2005
  • Diosgenin (25 (R) - spirost-5-en-3$\beta$ -ol) was oxidized with 2,3-dichloro -5,6-dicyano-1,4-benzoquinone to form 25(R)-1,4,6-spirostatrien-3-one (1) as rigid cyclic $\alpha$,$\beta$-unsaturated carbonyl compound. This compound was reacted with $H_{2}O_{2}$, m-chloroperoxybenzoic acid (mCPBA), NaOCl in the presence with (R,R)- or (S,S)-Jacobsen catalyst, tert-butyl-hydroperoxide (TBHP) in Mo$(CO)_{6}$, and in VO $(acac)_{2}$ catalyst, respectively, 25(R) -1,4,6-spirostatrien -3-one (1) was reduced with $NaBH_{4}$ L-Selectride, $LiAIH_{4}$,$BH_{3}$ $\cdot$$(CH_{3})_{2}S$, Superhydride, Red-Al, and lithium tri-tert-butoxyaluminium hydride. And 25(R)-4,6-spirostadien-3$\beta$-ol (4) was treated with $H_{2}O_{2}$, mCPBA, TBHP in D - (-) - and L-(+)-diisopropyltar-trate and $Ti(OiPr)_{4}$ condition (Sharpless asymmetric epoxidation), TBHP in $Mo(CO)_{6}$, and in $VO(acac)_{2}$ catalyst, respectively.

The Effect of Animosity Type on Consumer Cognition and Consumption Behavior Direction : Based on the Moderating Role of Fear of Missing Out (국가간 적대감 유형이 소비자 인지와 소비행동 방향에 미치는 영향 : 고립공포감의 조절효과를 중심으로)

  • Il-Hwan Ma
    • Korea Trade Review
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    • v.47 no.5
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    • pp.321-336
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    • 2022
  • The purpose of this study aims to investigate how consumer awareness and purchasing behavior are affected by the type of animosity against the nation. This study classified animosity into three categories: sociocultural, economic, and war-based. Additionally, the consumer's cognition toward animosity was split into two categories-empathic concernt and personal distress-and the direction of consumption behavior was split into two categories-individual brand avoidance behavior and collective bandwagon behavior. The concept of Fear of Missing Out (FoMO) was introduced for the direction of consumption behavior, further validating the moderating impact. Structural equation modeling method was used to measure the general consumption behvior of Korean consumers' animosity. The results were analyzed using a total of 279 samples. As a result, animosity motivated by war and by economics had a substantial impact on empathic concern, while animosity motivated by socioculture had a significant impact on personal distress. Personal distress had a good impact on an individual's brand antipathy behavior, which in turn led to brand dislike and avoidance. Empathic concern also had a positive impact on the phenomena of group sympathy, which leads to identification of conduct and social conformity. Also, it was proven that the group that had a high level of FoMO reacted strongly to the phenomenon of group collective behavior.