• Title/Summary/Keyword: 부분 유입

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Application of Multiplex RT-PCR for Simultaneous Identification of Tomato Spotted Wilt Virus and Thrips Species in an Individual Thrips on Chrysanthemum (시설재배 국화에서 총채벌레의 종 동정 및 보독 바이러스 동시 검출을 위한 다중 진단법 적용)

  • Yoon, Ju-Yeon;Yoon, Jung-Beom;Seo, Mi-Hye;Choi, Seung-Kook;Cho, In-Sook;Chung, Bong-Nam;Yang, Chang Yeol;Gangireddygari, Venkata Subba Reddy
    • Research in Plant Disease
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    • v.26 no.4
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    • pp.264-271
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    • 2020
  • We have developed a simultaneous diagnostic method that can identify both the species of thrips and tomato spotted wilt virus (TSWV) that are problematic in chrysanthemum plants. This is a method of amplifying DNA by performing reverse transcription-polymerase chain reaction by simultaneously adding primers specific to TSWV coat protein (N) gene and primers specific to the internal transcribed spacer 2 region of Frankliniella occidentalis and F. intonsa using total nucleic acid extracted from one thrips. The sizes of DNA fragments for TSWV, F. occidentalis, and F. intonsa were 777, 287, and 367 bp, respectively. These results showed species identification of thrips and whether thrips carrying TSWV can be simultaneously confirmed. Further usefulness of the simultaneous diagnostic method was made from greenhouse survey at chrysanthemum greenhouses in Taean (Chungcheongnam-do) and Changwon (Gyeongsangnam-do) to investigate the identification of thrips species and the rate of thrips carrying TSWV. Of thrips collected from the greenhouses, 83.7% thrips was F. occidentalis and 72.9% F. occidentalis carried TSWV in Taean. Similarly, the diagnostic method showed that 92.2% thrips was F. occidentalis and 84.0% F. occidentalis carried TSWV in Changwon. These results confirm that F. occidentalis is a dominant thrips species and the thrips species plays a crucial role in the transmission of TSWV in chrysanthemum plants in the greenhouses. Taken together, this study showed a simple diagnostic method for thrips identification and epidemiological studies of the timing and spread of TSWV through thrips in chrysanthemum greenhouses in South Korea.

Design and Economic Analysis of Low Pressure Liquid Air Production Process using LNG cold energy (LNG 냉열을 활용한 저압 액화 공기 생산 공정 설계 및 경제성 평가)

  • Mun, Haneul;Jung, Geonho;Lee, Inkyu
    • Korean Chemical Engineering Research
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    • v.59 no.3
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    • pp.345-358
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    • 2021
  • This study focuses on the development of the liquid air production process that uses LNG (liquefied natural gas) cold energy which usually wasted during the regasification stage. The liquid air can be transported to the LNG exporter, and it can be utilized as the cold source to replace certain amount of refrigerant for the natural gas liquefaction. Therefore, the condition of the liquid air has to satisfy the available pressure of LNG storage tank. To satisfy pressure constraint of the membrane type LNG tank, proposed process is designed to produce liquid air at 1.3bar. In proposed process, the air is precooled by heat exchange with LNG and subcooled by nitrogen refrigeration cycle. When the amount of transported liquid air is as large as the capacity of the LNG carrier, it could be economical in terms of the transportation cost. In addition, larger liquid air can give more cold energy that can be used in natural gas liquefaction plant. To analyze the effect of the liquid air production amount, under the same LNG supply condition, the proposed process is simulated under 3 different air flow rate: 0.50 kg/s, 0.75 kg/s, 1.00 kg/s, correspond to Case1, Case2, and Case3, respectively. Each case was analyzed thermodynamically and economically. It shows a tendency that the more liquid air production, the more energy demanded per same mass of product as Case3 is 0.18kWh higher than Base case. In consequence the production cost per 1 kg liquid air in Case3 was $0.0172 higher. However, as liquid air production increases, the transportation cost per 1 kg liquid air has reduced by $0.0395. In terms of overall cost, Case 3 confirmed that liquid air can be produced and transported with $0.0223 less per kilogram than Base case.

A Changes in China's Landscape Scenic Sites System and Suggestions for Application of Major Policies to Scenic Sites of Korea (중국 풍경명승구 제도의 변천과 주요정책의 국내 명승 적용 제언)

  • Kim, Dong-Hyun;Lee, Jian-Feng;Shin, Hyun-Sil
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.41 no.2
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    • pp.11-18
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    • 2023
  • This study aims to distinguish what can be used in consideration of the national situation with Korea for Chinese Scenic and Historic Interest Areas, and the results are as follows; First, the Chinese Scenic and Historic Interest Areas expanded to the existing scenic cruise culture, travel, and tourism culture in the process of the influx of Western culture in the modern and contemporary era, and became popular as a travel destination. Accordingly, the Chinese government developed the tourism industry around the scenic sites, and thanks to the development of transportation and communication, the Scenic and Historic Interest Areas has become an important national heritage. This influenced the establishment of the system related to Scenic and Historic Interest Areas, and today, it is operated around the Scenic and Historic Interest Areas ordinance. Second, the designation of the Scenic and Historic Interest Areas is divided into the size of the site according to the area, and the process of selecting the Scenic and Historic Interest Areas classification, rating evaluation, and comprehensive value evaluation according to evaluation indicators and rating standards is carried out. Accordingly, according to the results of the classification, it is subdivided from the national level to the Scenic and Historic Interest Areas at the local level. Third, the central government is in charge of managing and supervising Scenic and Historic Interest Areas across the country, and the local government's construction department is in charge of supervising Scenic and Historic Interest Areas in the region. The management organization of Scenic and Historic Interest Areas established by local governments above the county level has a system that actually protects, utilizes, and manages Scenic and Historic Interest Areas. In addition, 14 detailed indicators are used to monitor Scenic and Historic Interest Areas. Based on these results, considering the application of the domestic scenic site policy, the method of developing the policy that has established the system from the perspective of the utilization of the people is worth considering. On the other hand, the evaluation of the designation and management system through the setting of various indicators has limitations in that it is difficult to secure objectivity in impressing or evaluating the landscape. Therefore, rather than blindly introducing quantified evaluation, it seems that guidance and promotion on how to expand consensus on scenic values and enjoy heritage should be prioritized.

An Economic Value for the First Precipitation Event during Changma Period (장마철 첫 강수의 경제적 가치)

  • Seo, Kyong-Hwan;Choi, Jin-Ho
    • Atmosphere
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    • v.32 no.1
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    • pp.61-70
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    • 2022
  • This study evaluates the economic values for the several first precipitation events during Changma period. The selected three years are 2015, 2019, and 2020, where average precipitation amounts across the 58 Korean stations are 12.8, 20.1 and 13.3 mm, respectively. The four categories are used to assess the values including air quality improvement, water resource acquisition/accumulation, drought mitigation, and forest fire prevention/recovery. Economic values for these three years are estimated 50~150 billion won. Among the four factors considered, the effect of air quality improvement is most highly valued, amounting to 70 to 90% of the total economic values. Wet decomposition of air pollution (PM10, NO2, CO, and SO2) is the primary reason. The next valuable element is water resource acquisition, which is estimated 9~15 billion won. Effects of drought mitigation and fire prevention are deemed relatively small. This study is the first to estimate the value of the precipitation events during Changma onset. An analysis for more Changma years will be performed to achieve a more reliable estimate.

Study on the Characteristics of the Slow-moving Landslide (Landcreep) in the Sanji Valley of Jinju (진주시 산지골 유역내 땅밀림지 특성에 관한 연구)

  • Park, Jae-Hyeon;Kim, Seon Yeop;Lee, Sang Hyeon;Kang, Han Byoel
    • Journal of Korean Society of Forest Science
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    • v.111 no.1
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    • pp.115-124
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    • 2022
  • This study was conducted to obtain basic data that could help prevent damage caused by slow-moving landslides (land-creep). Specifically, the geological, topographic, and physical characteristics of land-creep were analyzed in Jiphyeon-myeon, Jinju-si. The first and second analyzed land-creeps occurred in 1982 and 2019, respectively. The area damaged in the second land-creep was about 11.5-fold larger than that damaged in the first land-creep. The dominant constituent rock in the land-creep area was sedimentary rock, which seems to be weakly resistant to weathering. The areas that collapsed due to land-creep were related to the presence of separated rocks between the bedding plane in the estimated activity surface over the slope direction and the vertically developed joint surface. Thus, surface water and soil debris were introduced through the gaps of separated rocks. Additionally, the areas collapsed due to the combination of the bedding plane and joint surface shale and sandstone showed an onion structure of weathered outcrop from the edge to inner part caused by weathering from ground water. Consequently, core stones were formed. The study area was a typical area of land-creep in a mountain caused by ground water. Land-creep was classified into convex areas of colluvial land-creep. The landslide-risk rating in the study area was classified into three and five classes. The flow of ground water moved to the northeast and coincided with the direction of the collapse. Soil bulk density in the collapsed area was lower than that in ridge area, which was rarely affected by land-creep. Thus, soil bulk density was affected by the soil disturbance in the collapsed area.

An Oral History Study of Overseas Korean Astronomer: John D. R. Bahng's Case (한국천문연구원 원외 원로 구술사연구 - 방득룡 전임 노스웨스턴 대학교 천문학 교수 사례 -)

  • Choi, Youngsil;Seo, Yoon Kyung;Lee, Hyung Mok
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.73.4-74
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    • 2021
  • 한국천문연구원은 2017년 제1차 구술채록사업에 이어 2020년 제2차 사업을 진행하면서 최초로 원외 원로에 대한 구술채록을 시도하였다. 국가 대표 천문연구의 산실로서 연구원 존재 의의를 확립하기 위하여 원내 원로에 국한되었던 구술자 대상을 확장한 것이다. 그 첫 외부 구술 대상자로 방득룡 전임 노스웨스턴 천문학과 교수를 선정하여 2020년 7월부터 준비단계에 들어갔다. 방득룡 전(前)교수가 첫 번째 한국천문연구원 원외 인사 구술자로 선정된 이유는, 그가 우리나라 천문대1호 망원경 구매 선정에 개입한 서신(1972년)이 자료로 남아있었기 때문이다. 한국천문연구원에서 2017년에 수행한 제1차 구술채록사업에서 구술자로 참여한 오병렬 한국천문연구원 원로가 기증한 사료들은 대부분 연구원 태동기 국립천문대 구축과 망원경 구매 관련 자료였으며 이 가운데 1972년 당시 과학기술처 김선길 진흥국장에게 Boller and Chivesns(사(社))의 반사경을 추천한 방득룡 전(前)교수의 서신은 한국 천문학 발전사에서 중요한 사료였다. 연구진은 이 자료를 시작으로, 방득룡 전(前)교수의 생존 여부와 문서고의 공기록물들에서 그의 흔적을 찾아가기 시작했다. 놀랍게도 그는 실제 세계와 한국천문연구원 문서고 깊숙이 기록물들 모두에서 상존하고 있었다. 1927년생인 방득룡 전(前)교수, Dr. John D. R.은 미국 플로리다 한 실버타운에서 건강한 정신으로 생존하여 있었고 연구진의 인터뷰에 흔쾌히 응했다. 2020년 9월 16일에 한국천문연구원 본원 세종홀 2층 회의실에서 영상통신회의로 그와의 구술인터뷰가 진행되었다. 이 구술인터뷰는 원외 인사가 대상이란 점 외에도 방법적으로는 전형적인 대면 방식이 아닌 영상 인터뷰였다는 점에서 코로나 시대의 대안이 되는 실험적 시도였다. 현대 한국천문학 발전사의 재조명 측면에서도 의미가 있었다. 1960년대 초반부터 1992년 정년퇴임까지 30년을 미국 유수 대학교 천문학과 교수로 재직하며 활발한 활동을 해 온 한국계 천문학자가 우리나라 최초 반사망원경 구매 선정에 적극 개입하였던 역사는, 공문서 자료들과 서신 사료들에 이어 그의 육성으로 나머지 의구심의 간극이 채워졌다. 또 구술자 개인이 주관적으로 중요하다고 여기는 '기억'이 중요한 아카이빙 콘텐츠 확장의 단초가 될 수 있다는 것을 보여줌으로써 구술사 연구에 있어서도 중요한 관점을 주었다. 애초 연구진이 방득룡 전(前)교수의 공식 기록에서 아카이빙의 큰 줄기로 잡았던 것은 1948년 도미, 1957년 위스콘신 대학교 천문학 박사학위 취득, 1962년부터 노스웨스턴 대학(일리노이주 에반스턴)의 천문학 교수진, 1992년 은퇴로 이어진 생애였다. 그러나 그와의 구술 준비 서신 왕래와 구술을 통하여 알게 된 그가 인생에서 중요시 여겼던 지점은, 1948년 도미 무렵 한국의 전쟁 전 상황과 당시 비슷한 시기에 유학한 한국 천문학자들의 동태, 그리고 1957년부터 1962년까지 프린스턴 대학교에서 M. Schwarzschild 교수와 L. Spitzer 교수를 보조하며 Stratoscope Project를 연구하였던 경험이었다. 기록학적 의미에서도, 전자를 통해서 그와 함께 동시대 한국 천문학을 이끌었던 인재들의 맥락정보를 얻을 수 있었으며, 후자를 통해서는 세계 천문학사에 큰 영향을 미친 석학에 대한 아카이브 정보와의 연계 지점과 방득룡 전(前)교수의 연구 근원을 찾을 수 있었다. 이들은 추후 방득룡 콘텐츠 서비스 시에 AIP, NASM, Lyman Spitzer 콘텐츠, 평양천문대, 화천조경천문대, 서울대와 연세대, 그리고 한국천문연구원까지 연계되어 전 세계 폭넓은 이용자들의 유입을 유도할 수 있는 검색 도구가 될 수 있다. 이번 방득룡 구술사 연구에서 구술자 개인의 주관적인 소회가 공식 기록이 다가갈 수 없는 역사적 실체에 일정 부분 가까울 수 있다는 것, 그리고 이를 통하여 개인의 역사는 공동체의 역사로 확장될 수 있다는 사실을 발견할 수 있었다. 또 연구진은 방득룡 전(前)교수의 회상을 통하여 구술자 개인의 시각으로 한국과 미국 천문학계의 공동체 역사를 재조명할 수 있었고, 이것을 아카이브 콘텐츠 확장 서비스에 반영할 수 있다는 기대를 가지게 되었다. 무엇보다 이 연구를 통하여 다양한 주제의 아카이브로 연동될 수 있는 주제어와 검색도구를 구술자 개인의 회상으로부터 유효하게 도출할 수 있다는 것을 확인하였다. 그리고 향후 한국천문 구술아카이브의 확장을 통하여 보다 다양한 활용과 연구 재활용의 선순환이 가능하다는 것도 알 수 있었다. 이는 최근 기록학계에서 대두되고 있는 LOD(Linked Open Data)의 방향성과도 흡사하여 한국천문학 구술사연구의 차세대 통합형 기록관리의 미래모형을 기대케 하는 대목이다.

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The significance and structural improvement of burial mound in Geonwonneung and Heonneung in the early Joseon Dynasty - Focusing on the Byeongpungsadaeseok and Nanganseok - (조선초 건원릉과 헌릉의 봉릉 구조개선과 의의 - 병풍사대석과 난간석을 중심으로 -)

  • SHIN Jihye
    • Korean Journal of Heritage: History & Science
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    • v.55 no.4
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    • pp.118-135
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    • 2022
  • The primary purpose of this study is to estimate the structure of Byeongpungsadaseok (屛風莎臺石) and Nanganseok (欄干石) in Geonwonneung (建元陵) and Heonneung (獻陵), which were built in the early of 15th century, based on the Annals of King Sejong. In addition, the ultimate purpose of this study is to reveal structural changes and their significance by comparing the differences with the contents of the dismantlement survey. Geonwonneung, Jereung(齊陵), and Heonneung were repaired at the same time in 1442, and the structural changes were the similar. The purpose of the repair in 1442 was to prevent water from flowing into the underground palace with smooth drainage. As a result of estimating the structure of Geonwonneung and Heonneung according to the records of the Annals of King Sejong, it was created in a very similar form to the Hyeonneung and Jeongneung of Goryeo. And it was clearly recognized that the Royal Tomb of Goryeo was followed. However, as the structure was improved in 1442, the unique characteristics of the Royal Tomb of the Joseon Dynasty were formed. First is the appearance of the Bokbuhyeong lime (覆釜形石灰, which is a convex roof on the Byeongpungsadaseok that serves to prevent rainwater from penetrating into the burial mound. It also plays a role in connecting and fixing the Manseok (滿石) and the Inseok (引石), which are the upper structures of the Sadaseok (莎臺石). Second, the Bakseok (薄石) between the nanganseok and the sadaseok has been transformed into the Sangseok (裳石) with a slope. This plays a role in protecting the inner stone chamber by expanding the length of the bakseok, which forms an overall slope, like the eaves of the roof. After both of these features were first attempted in 1442, they were applied to all Royal Tombs of the Joseon Dynasty and became unique features of these Royal Tombs.

The formal and intrinsic characteristics of the Changgeuk album (1971) and the meaning of the material (음반 창극 <사명대사>(1971)의 형식적·내용적 특징과 자료의 의미)

  • Song, So-Ra
    • (The) Research of the performance art and culture
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    • no.39
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    • pp.457-507
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    • 2019
  • The purpose of this study is to explore the formal and content features of the material for the Changgeuk album , which was produced and released in 1971. Changgeuk album was produced and published as a headword for "Changgeuk". However, it differs from the style of Changgeuk which is treated as a stage drama in that the narrative is developed around the commentary and dialogue in the formal aspect and the Pansori is only partially used. The styles of Changgeuk, implemented through gramophone record, radio broadcasts and television broadcasts, varied widely, unlike those of Changgeuk established in the 1930s. Pansori music wasn't the only center, and traditional performers weren't even the main members of the play. The characteristic form of the Changgeuk album is an experiment of Changgeuk that emerged naturally with radio reading and the advent of radio dramas in the 1950s and 1960s. So it is necessary to pay attention to the Changgeuk album in that it shows diverse forms of experiments conducted by Changgeuk in the newly introduced culture and media in the middle and late 20th century As for the contents of the Changgeuk album , the work embraces Lee Jong ik 's novel (1957), but develops the narrative centering on the life of Saint Sa-myung(四溟大師). And it is faithfully portraying the life of a Buddhist monk and the national salvation hero who pursued the original work. This content composition can be understood in the will of singer Lee Yong bae, the soundman who produced the album, and in the flow of historical dramas that summon the historical hero of the old country of the time to the stage. Singer Lee Yong bae reflects on his life in the past when he was full of greed and conceit through his life as a monk of Saint Sa-myung(四溟大師) and is greatly impressed by the personal aspect of Saint Sa-myung(四溟大師), and these emotions encouraged his creative will. Also, the Changgeuk record is meaningful in that it is one of the specific materials that embodies the national hero as a record and a traditional play under the discourse of the people, the nation in the 1970s.

Stable Isotope and Fluid Inclusion Studies of the Daebong Gold-silver Deposit, Republic of Korea (대봉 금-은광상에 대한 유체포유물 및 안정동위원소 연구)

  • 유봉철;이현구;김상중
    • Economic and Environmental Geology
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    • v.36 no.6
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    • pp.391-405
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    • 2003
  • The Daebong gold-silver deposit consists of mesothermal massive quartz veins thar are filling the fractures along fault shear (NE, NW) Bones within banded or granitic gneiss of Precambrian Gyeonggi massif. Based on vein mineralogy, ore textures and paragenesis, ore mineralization of this deposits is composed of massive white quartz vein(stage I) which was formed in the same stage by multiple episodes of fracturing and healing, and transparent quartz vein(stage II) which is separated by a major faulting event. Stage I is divided into the 3 substages. Ore minerals of each substages are as follows: 1) early stage I=magnetite, pyrrhotite, arsenopyrite, pyrite, sphalerite, chalcopyrite, 2) middle stage I=pyrrhotite, arsenopyrite, pyrite, marcasite, sphalerite, chalcopyrite, galena, electrum and 3) late stage I=pyrite, sphalerite, chalcopyrite, galena, electrum, argentite, respectively. Ore minerals of the stage II are composed of pyrite, sphalerite, chalcopyrite, galena and electrum. Systematic studies (petrography and microthermometry) of fluid inclusions in stage I and II quartz veins show fluids from contrasting physical-chemical conditions: 1) $H_2O-CO_2-CH_4-NaCl{\pm}N-2$ fluid(early stage I=homogenization temperature: 203∼3$88^{\circ}C$, pressure: 1082∼2092 bar, salinity: 0.6∼13.4 wt.%, middle stage I=homogenization temperature: 215∼28$0^{\circ}C$, salinity: 0.2∼2.8 wt.%) related to the stage I sulfide deposition, 2) $H_2O-NaCl{\pm}CO_2$ fluid (late stage I=homogenization temperature: 205∼2$88^{\circ}C$, pressure: 670 bar, salinity: 4.5∼6.7 wt.%, stage II=homogenization temperature: 201-3$58^{\circ}C$, salinity: 0.4-4.2 wt.%) related to the late stage I and II sulfide deposition. $H_2O-CO_2-CH_4-NaCl{\pm}N_2$ fluid of early stage I is evolved to $H_2O-NaCl{\pm}CO_2$ fluid represented by the $CO_2$ unmixing due to decrease in fluid pressure and is diluted and cooled by the mixing of deep circulated meteoric waters ($H_2O$-NaCl fluid) possibly related to uplift and unloading of the mineralizing suites. $H_2O-NaCl{\pm}CO_2$ fluid of stage II was hotter than that of late stage I and occurred partly unmixing, mainly dilution and cooling for sulfide deposition. Calculated sulfur isotope compositions ({\gamma}^{34}S_{H2S}$) of hydrothermal fluids (3.5∼7.9%o) indicate that ore sulfur was derived from mainly an igneous source and partly sulfur of host rock. Measured and calculated oxygen and hydrogen isotope compositions ({\gamma}^{18}O_{H_2O}$, {\gamma}$D) of ore fluids (stage I: 1.1∼9.0$\textperthousand$, -92∼-86{\textperthansand}$, stage II: 0.3{\textperthansand}$, -93{\textperthansand}$) and ribbon-banded structure (graphitic lamination) indicate that mesothermal auriferous fluids of Daebong deposit were two different origin and their evolution. 1) Fluids of this deposit were likely mixtures of $H_2O$-rich, isotopically less evolved meteoric water and magmatic fluids and 2) were likely mixtures of $H_2O$-rich. isotopically heavier $\delta$D meteoric water and magmaticmetamorphic fluids.

The Spatio-temporal Distribution of Organic Matter on the Surface Sediment and Its Origin in Gamak Bay, Korea (가막만 표층퇴적물중 유기물량의 시.공간적 분포 특성)

  • Noh Il-Hyeon;Yoon Yang-Ho;Kim Dae-Il;Park Jong-Sick
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.9 no.1
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    • pp.1-13
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    • 2006
  • A field survey on the spatio-temporal distribution characteristics and origins of organic matter in surface sediments was carried out monthly at six stations in Gamak Bay, South Korea from April 2000 to March 2002. The range of ignition loss(IL) was $4.6{\sim}11.6%(7.1{\pm}1.6%)$, while chemical oxygen demand(CODs) ranged from $12.25{\sim}99.26mgO_2/g-dry(30.98{\pm}19.09mgO_2/g-dry)$, acid volatile sulfide(AVS) went from no detection(ND)${\sim}10.29mgS/g-dry(1.02{\pm}0.58mgS/g-dry)$, and phaeopigment was $6.84{\sim}116.18{\mu}g/g-dry(23.72{\pm}21.16{\mu}g/g-dry)$. The ranges of particulate organic carbon(POC) and particulate organic nitrogen(PON) were $5.45{\sim}23.24 mgC/g-dty(10.34{\pm}4.40C\;mgC/g-dry)$ and $0.71{\sim}2.99mgN/g-dry(1.37{\pm}0.58mgN/g-dry)$, respectively. Water content was in the range of $43.1{\sim}77.6%(55.8{\pm}5.6%)$, and mud content(silt+clay) was higher than 95% at all stations. The spatial distribution of organic matter in surface sediments was greatly divided between the northwestern, central and eastern areas, southern entrance area from the distribution characteristic of their organic matters. The concentrations of almost all items were greater at the northwestern and southern entrance area than at the other areas in Gamak Bay. In particular, sedimentary pollution was very serious at the northwestern area, because the area had an excessive supply of organic matter due to aquaculture activity and the inflow of sewage from the land. These materials stayed longer because of the topographical characteristics of such as basin and the anoxic conditions in the bottom seawater environment caused by thermocline in the summer. The tendency of temporal change was most prominently in the period of high-water temperatures than low-water ones at the northwestern and southern entrance areas. On the other hand, the central and eastern areas did not show a regular trend for changing the concentrations of each item but mainly showed a higher tendency during the low-water temperatures. This was observed for all but AVS concentrations which were higher during the period of high-water temperature at all stations. Especially, the central and eastern areas showed a large temporal increase of AVS concentration during those periods of high-water temperature where the concentration of CODs was in excess of $20mgO_2/g-dry$. The results show that the organic matters in surface sediments in Gamak Bay actually originated from autochthonous organic matters with eight or less in average C/N ratio including the organic matters generated by the use of ocean, rather than terrigenous organic matters. However, the formation of autochthonous organic matter was mainly derived from detritus than living phytoplankton, indicated the results of the POC/phaeopigment ratio. In addition, the CODs/IL ratio results demonstrate that the detritus was the product of artificial activities such as dregs feeding and fecal pellets of farm organisms caused by aquaculture activities rather than the dynamic of natural ocean activities.

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