• Geosciences Journal
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• 제22권6호
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• pp.989-1000
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• 2018

The provenance of the Central Yellow Sea Mud (CYSM) in the Yellow Sea has been attracted a great deal of attention over the last three decades, but a consensus is not yet reached. In this study, 101 surface sediment samples collected from the CYSM were investigated to determine provenance and transport mechanisms in the area using the clay minerals and major element components. The Huanghe sediments are characterized by higher smectite, but the Changjiang sediments are more abundant illite contents. Western Korean rivers contain more kaolinite and chlorite than do Chinese rivers. The Chinese rivers have higher $Fe_2O_3$, MgO, and CaO than the Korean rivers at the same $Al_2O_3$ concentration. Therefore, the clay minerals and major element concentrations can be useful indicator for the source. Based on our results, we suggest that the surface sediments in CYSM were composed mainly of Changjiang sediments, mixed a partly with sediments from the Huanghe and the western Korean rivers. Although the northwestern part of CYSM is proximate to the Huanghe, the contents of smectite and CaO were extremely low. It could be evidence that the Huanghe materials do not enter directly into the CYSM due to the Shandong Peninsula Front. Considering the oceanic circulation in the Yellow Sea, the Changjiang sediments could be transported eastward with the Changjiang Diluted Water and then mixed in CYSM via the Yellow Sea Warm Current (YSWC). Huanghe sediments could be provided by coastal currents (Shandong Coastal Current and Yellow Sea Coastal Current) and the YSWC. In addition, sediments from western Korean rivers might be supplied into the CYSM deposit via the Korean Coastal Current, Transversal Current, and YSWC.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2408-2412
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• 2013

We demonstrate herein the synthesis and modification of magnetic nanoparticles and its use in the immobilization of the lipase. Magnetic $Fe_3O_4$ nanoparticles (MNPs) were prepared by simple co-precipitation method in aqueous medium and then subsequently modified with tetraethyl orthosilicate (TEOS) and 3-aminopropyl triethylenesilane (APTES). Silanization magnetic nanoparticles (SMNP) and amino magnetic nanomicrosphere (AMNP) were synthesized successfully. The morphology, structure, magnetic property and chemical composition of the synthetic MNP and its derivatives were characterized using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) analysis, X-ray diffraction, superconducting quantum interference device (SQUID) and thermogravimetric analyses (TGA). All of these three nanoparticles exhibited good crystallization performance, apparent superparamagnetism, and the saturation magnetization of MNP, SMNP, AMNP were 47.9 emu/g, 33.0 emu/g and 19.5 emu/g, respectively. The amino content was 5.66%. The AMNP was used to immobilize lipase, and the maximum adsorption capacity of the protein was 26.3 mg/g. The maximum maintained activity (88 percent) was achieved while the amount of immobilized lipase was 23.7 mg $g^{-1}$. Immobilization of enzyme on the magnetic nanoparticles can facilitate the isolation of reaction products from reaction mixture and thus lowers the cost of enzyme application.

• ALGAE
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• 제26권1호
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• pp.41-50
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• 2011

Yellow Sea surface sediment samples collected on October 15-31, 2003 were analyzed using the palynological process to investigate the spatial distribution of dinoflagellate resting cysts. The sampling areas comprised four latitudinal transects, the northernmost of which was located off the Shandong Peninsula, China and the southernmost off Jeju Island, Korea. Each transect line was composed of six to nine stations, spanning the distance between the Chinese and Korean coasts. Twenty-five different types of dinoflagellate cysts were identified. Gonyaulax scrippsae, Alexandrium spp. (ellipsoidal type), and G. spinifera were the most dominant at all stations surveyed. Dinoflagellate cysts belonging to the Gonyaulacales comprised over 50% of all cysts collected. The latitudinal distribution trend showed that cyst concentrations along the two middle transects were much higher than those along the two northern and southern transects. Cyst concentrations in the offshore central areas reached their highest values within each transect and gradually decreased toward the Chinese and Korean coasts. Overall, cyst concentrations were markedly elevated in the offshore central Yellow Sea areas and gradually decreased outward in all four directions. This concentric cyst distribution pattern was consistent with the hydrographic features of the Yellow Sea, such as circular current systems, sedimentary properties, and water depth.

• 한국환경과학회지
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• 제23권12호
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• pp.1999-2014
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• 2014

A meteo-tsunami occurred along the coastline of South Korea on 31 March 2007, with an estimated maximum amplitude of 240 cm in Yeonggwang (YG). In this study, we investigated the synoptic weather systems around the Yellow sea including the Bohai Bay and Shandong Peninsula using a weather research and forecast model and weather charts of the surface pressure level, upper pressure level and auxiliary analysis. We found that 4-lows passed through the Yellow sea from the Shandung Peninsula to Korea during 5 days. Moreover, the passage of the cold front and the locally heavy rain with a sudden pressure change may make the resonance response in the near-shore and ocean with a regular time-lag. The sea-level pressure disturbance and absolute vorticity in 500 hPa projected over the Yellow sea was propagated with a similar velocity to the coastline of South Korea at the time that meteo-tsunami occurred.

• 수산해양기술연구
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• 제12권2호
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• pp.43-47
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• 1976

The large two-boat trawl is of importance in Korean fishery. It occupied 12.8% of total catches in 1974. The author analysed the reports of six large two-boat trawlers operated at the Yellow Sea and the East China Sea, in the term from September 1975 to March 1976. The results obtained are as follows; (1) 1,710 of total hauls are operated in the term, and the total catches amounted 559, 181kg. Then, 325kg of catch per unit effort (C. P. U. E) are obtained. The catches are specified into 28% of soles, 12% of shrimp, 8% of yellow corvenia, hair tail, kang-dari, and the rest of miscellanous fishes. (2) C. P. U. E. of the southern sectors of the Soheaksan Is. represented superior catches to compared with others sectors. (3) The monthly variation of C. P. U. E. between sea eel and yellow corvenia revealed positive correlation, whereas between sole and shlimp, between hair tail and rays revealed negative correlation respectively.

• Ocean and Polar Research
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• 제31권4호
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• pp.401-414
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• 2009

Yellow Sea Buoy (YSB) was moored in the center of the Yellow Sea at 35$^{\circ}$51'36"N, 124$^{\circ}$34'42"E, on 12 September 2007. YSB is a large buoy of 10 m diameter, and as such is more durable against collision by ships and less likely to be lost or removed by fishing nets compared to small ordinary buoys of 2.3 m diameter. YSB is equipped with 12 kinds of oceanic and meteorologic instruments, and transfers its realtime observation data to KORDI through ORBCOMM system every 1 hour. Data on ocean winds, air temperature, air pressure, and sea temperature appear to be accurate, while water property sensors (AAQ1183), which are sensitive to fouling, are producing errors. YSB (2007), Ieodo ocean research station (2003), and Gageocho ocean research station, which was completed in October 2009, will establish the 2 degrees interval by latitude in the Yellow Sea, and they will contribute though the 'Operational Oceanography System' as the important realtime observation network.

• 한국수산과학회지
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• 제30권4호
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• pp.601-607
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• 1997

해양오염의 진단을 위한 생화학적 오염지표 설정의 기초연구의 일환으로서 오염이 심각한 서해산 (황해) 도다리 (Pleuronichthys conutus)의 혈액의 지질성분을 분석 평가하였다. 서해안의 자연산 도다리의 혈액중의 헤모글로빈의 함량은 동해안 포항의 자연산 도다리 대비 $15\~30\%$의 현저한 감소현상이 나타나서 서해안의 내해 (內海) 뿐만 아니라 외해 (外海)의 오염도 상당히 심각함을 알 수 있었다. 서해안의 자연산 도다리의 혈청중의 중성지질 (TG)의 함량도 포항의 자연산 도다리의 혈청중의 TG의 함량 대비 $15\~50\%$나 유의적으로 높았다. 서해안 자연산 도다리의 혈청중의 총콜레스테롤의 함량은 포항의 자연산 도다리의 혈청중의 총콜레스테롤의 함량 대비 아산과 서산은 $20\~25\%$나 높았지만, 격포나 보령은 차이가 없었다. 서해안의 자연산 도다리의 혈청 중의 LDL-콜레스테롤의 함량도 각각 $15\~35\%$나 유의적으로 높았지만, HDL-콜레스테롤의 함량의 증가는 거의 인정할 수 없었다. 또한 서해안의 자연산 도다리의 동맥 경화지수는 포항의 자연산 도다리의 동맥경화지수 대비 각각 $10\~60\%$의 유의적인 증가효과가 인정되었다. 질병이나 노화와 함께 증가되는 것으로 알려진 인지질에 대한 총콜레스테롤의 함량비 (T-Chol/PL ratio)는 서해안의 자연산 도다리의 T-Chol/PL비가 포항의 자연산 도다리의 T-Chol/PL비와 거의 유사한 값을 나타내고 있었다. 이상의 결과에서 볼 때 서해안의 자연산 도다리의 오염도 서해안의 넙치와 마찬가지로 병적상태로 오염의 정도가 상당히 심각할 것으로 판단된다. 이러한 사실은 서해안의 수질환경이 공장폐수 및 육상오수의 유입, 그리고 농약 등의 오염원에 노출되어 있다는 사실을 알 수 있다.

• 환경영향평가
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• 제21권3호
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• pp.445-460
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• 2012

In order to evaluate and predict the environmental impact of the low-trophic-level ecosystem to environmental changes in the Yellow Sea and the East China Sea, an ecological modelling study was undertaken. Simulation results of average distribution patterns and concentrations of water quality factors during the summer by the model were acceptable. Phytoplankton and remineralization rate of organic matter were very important parameters by a sensitivity analysis. Water quality factors showed high values in the estuary of the Yangtze River and in the West and South Sea of Korea and low values in the central area of the Yellow Sea. There is a plume of high values, especially nutrients, off the mouth of the Yangtze that expands or contracts with changes in the discharge strength. Characteristics of responses of water quality factors vary for different scenarios of environmental change, such as land-based pollution sources and atmospheric forcing. It is suggested that changes of light intensity, discharges of input sources, and wind play an important role in the marine ecosystem.

• 수산해양기술연구
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• 제14권2호
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• pp.113-116
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• 1978

우리나라 근해의 열 에너지 이용 가능성을 알기 위하여 황해 동부해역의 연직온도차 분포상황 및 그 계절적 변동을 조사하였고, 이들과 해수유동과의 관련성에 관하여 고찰하였다. 하계에는 거안 약 40mile 해역인 125${\circ}$30'E 이서의 34${\circ}$N이북에 연직온도차가 16$^{\circ}C$ 이상 되는 곳이 존재하는 바, 이것은 따뜻한 황해 난류계수의 표면가열과 저층의 황해냉수에 기인하는 것으로 생각된다. 연안으로 갈수록 연직 온도차는 줄어지고, 거안 약 30mile 해역에서는 약 1$0^{\circ}C$이다. 이를 이용하여 온도차발전이 가능하다고 보아진다. 제주도 남부 및 서부해역은 연직 온도차가 약 14$^{\circ}C$ 이상을 보인다. 겨울에는 왕성한 대류혼합으로 연직 온도차는 거의 없어진다. 그러나 겨울에는 강한 계절풍이 계속 발전체계를 여름에는 온도차발전, 겨울에는 파력 및 풍력발전을 하는 방식으로 체계화하면 주년 계속 발전이 가능할 것이라 생각된다.

• 한국광물학회지
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• 제20권3호
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• pp.203-212
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• 2007

2001년 황해 2차 탐사에서 채취된 89개 표층 퇴적물 시료에 대하여 고분해능 X선 회절분석기와 Siroquant v.3.0 프로그램을 이용하여 광물조성을 구하였다. 황해 표층 퇴적물은 주구성광물(석영 57.8%, 사장석 16.0%, 알카리 장석 10.0%), 점토광물 및 방해석 등으로 구성되어 있다. 점토광물 중에는 일라이트(8.7%)가 가장 많고, 녹니석(2.6%)이 두번째로 많으며, 카올리나이트(0.6%)는 매우 소량들어 있고, 스멕타이트는 존재하지 않는 것으로 밝혀졌다. 석영 함량은 황해의 가장자리에 많고, 산동 반도 남동쪽에서 제주도 남서쪽을 연결하는 북서-남동 방향을 따른 해역에서 매우 낮다. 이런 분포 경향은 조립질 퇴적물인 모래의 분포 경향과 일치한다. 이를 통하여 조립질 퇴적물은 많은 양의 석영으로 구성되어 있으며, 황해의 동쪽과 남서쪽으로 많은 양이 유입되었을 가능성이 크다고 추정할 수 있다. 일라이트의 분포는 석영과 반대되며, 세립질 퇴적물과 비슷한 경향을 나타낸다. 이것은 세립질 퇴적물의 상당한 양이 황해의 북서쪽으로부터 공급되었을 가능성을 보여준다. 이번 연구 결과만 가지고 황해 퇴적물의 근원지를 정확하게 규명하는 것은 힘들기 때문에, 이와 비슷한 일련의 연구가 계속되어야 할 것으로 판단된다.