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41.
Jong Hyuk Park Jianhua Ma Laurence T. Yang Anind K. Dey 《Mathematical Geosciences》2009,41(8):955-956
Announcement
2008 Best Paper Award 相似文献42.
Young-Ji Han Pyung-Rae Kim Gang-San Lee Jae-In Lee Seam Noh Seok-Min Yu Kwang-Su Park Kwang-Seol Seok Hyuk Kim Young-Hee Kim 《Environmental Earth Sciences》2017,76(10):361
Mercury (Hg) concentrations in air, effluent water, landfill gas, leachate, groundwater, and soil at a hazardous solid waste landfill site in Korea were measured along with air–soil surface Hg exchange fluxes at the site. The concentrations and fluxes were considerably higher than have been found elsewhere in Korea. Gaseous Hg concentrations in the air peaked during the day, coinciding with Hg being released from the landfill surface. This suggests that air–soil exchange increased the Hg concentrations in the atmosphere. The air–soil exchange flux increased abruptly when solar radiation reached the soil surface. The Hg flux peaked about 3 h before the solar radiation peaked, possibly because reducible Hg was abundant at the soil surface. The Hg emission flux activation energy (E a) was low, indicating that the Hg species present and Hg–soil binding were probably not as important (because of the high Hg content of the soil) as in previous studies. The methylmercury to total Hg ratios in the discharged effluent, groundwater, and leachate was clearly higher than typically found in coastal water and freshwater, suggesting bacteria caused active methylation to occur under the reducing conditions in the anaerobic landfill. The results suggested that considerable amounts of Hg are probably transported from the landfill to nearby environmental media and that this will continue if waste with a high Hg content continues to be added to the landfill without being pretreated. 相似文献
43.
Sang-kon Kim Maeng-eon Park Seung-gyun Baek Kyu-youl Sung Sun-ok Kim Hee-yul Park 《世界地质(英文版)》2004,7(2)
Chemical composition, Raman microspectrometry, and Fourier transform infrared (FT-IR) and SEM-CL (Cathodluminescence) analyses are carried out for Tanzania and Madagascar garnets for locality identification. Inclusion study was sustained after electron probe microanalysis (EPMA). Needle-like illmenites, apatites and zircons were the most common solid inclusions in Tanzania garnets. Madagascar garnets revealed rutile needles and apatites were also observed, but differences in size, shape and distribution patterns were noticed compared to Tanzania garnets. Tanzania garnets exhibited all types of observable fluid inclusions such as "fingerprint" pattern, called Type Ⅰ-A, liquid-only (L) single phase fluid inclusion, called Type Ⅰ-B and Type Ⅱ-A (L + S), Type Ⅱ-B (L + V) and Type Ⅲ-A (L + Sylvite +S), Type Ⅲ-B (L+S+V), while no more than two phase fluid inclusions found in both Madagascar and Korea garnets even if all examined garnets from three localities retained "fingerprint" features, so called, partially healed fractures, in common. Chemical composition, Raman microspectrometry and Fourier transform infrared (FT-IR) analysis taken turned out to be useful methods for the purpose of this study. Using consequences of SEM-CL and inclusion study, accordingly,the locality identification of gem-quality garnets is capable of being available in further application for other kinds of gemstones. 相似文献
44.
伴随韩国雨季开始和结束早晚的关联场分析 总被引：4，自引：0，他引：4
分析了与韩国雨季开始和结束的年际变化相关联的一些要素场发生的变化。分别对雨季开始和结束早晚的个例进行了合成分析。６月月平均资料用来分析与雨季开始早晚相关联的要素场变化，而在分析与雨季结束早晚相关联的要素场变化时则利用７月月平均资料。结果表明，对应雨季开始（或结束）早晚，大气环流和表面温度等要素不仅在东亚地区、而且在远离东亚的地方具有显著的差异。在东亚地区的显著差异主要是高空急流和西太平佯副热带高压。远离东亚的显著差异主要是印度季风和ＥＮＳＯ现象。印度季风与韩国雨季开始和结束均有关联，但ＥＮＳＯ现象只与雨季开始显著相关、而与结束并没有显著的关联。 相似文献
45.
Butyl- and phenyltin residues in bivalves were quantified around the coast of Korean peninsula in 1995–1998 and 2001. Butyltin compounds were detected at all the sites surveyed, whereas phenyltins were detected at 41 out of 67 sites in 1995–1998. Tributyltin (TBT) concentrations in bivalves ranged 48–2800 ng Sn/g on dry weight basis. Triphenyltin (TPT) concentrations ranged <3–1820. The mean TPT concentration was 3.5 times less than that of TBT. Spatial distribution of TBT was closely related to boating and dry-docking activities. TPT concentration in bivalves showed significant correlation with TBT. Concentrations of TBT in bivalves, 2001 are not significantly changed compared to those in 1995–1998. However, TPT concentrations in bivalves steeply decreased in 2001. High concentration of TBT and lesser extent TPT and their nation-wide distribution indicate that organotins are one of major organic pollutants in the marine environment of Korea. 相似文献
46.
Mussels (Mytilus galloprovincialis) were transplanted to seven stations around a large shipyard for 126 days to evaluate tributyltin (TBT) contamination. Although the application of TBT-based paints to ships is totally banned in Korea, butyltin compounds were found to accumulate in mussels following transplantation. Concentrations of TBT and total butyltins in transplanted mussels near the shipyard were in the range of 40-350 ng Sn/g and 74-530 ng Sn/g on a dry weight basis, respectively. Obviously, low TBT concentrations (6.0-53 ng Sn/gdw) were determined in mussels at four stations outside the shipyard. A negative gradient of TBT concentrations and TBT portion to total butyltin concentrations were found in both the surface water and transplanted mussels according to distance from the shipyard. In addition, TBT concentrations in surface water and transplanted mussels showed significant correlation (r(2) = 0.71; p < 0.001). These results indicate that the shipyard still releases fresh TBT into surrounding waters even after TBT regulation in Korea, and mussel transplantation is useful in evaluating TBT contamination in shipyard area. 相似文献
47.
Lee Minji Kim Jin Ho Kim Yun-Bae Park Chan Hong Shin Kyoungsoon Baek Seung Ho 《海洋学报(英文版)》2020,39(2):107-122
The East Sea(Sea of Japan)is a marginal,semi-closed sea in the northwestern Pacific.The Ulleung Basin area,which is located near the subpolar front of the East Sea,is known to have high primary production and good fisheries in spring season.After episodic wind-driven events during the spring of 2017,horizontal and vertical profiles of physical chemical biological factors were investigated at 29 stations located in the Ulleung Basin area.In addition,growth responses of phytoplankton communities to nutrient additions were evaluated by bioassay experiments to understand the fluctuation of phytoplankton biomass.Because of strong northwestern wind,phytoplankton biomass was scattered and upwelling phenomenon might be suppressed in this season.The phytoplankton abundances in the coastal stations were significantly higher than offshore and island stations.In contrast,the nutrient and chlorophyll a(Chl a)concentrations and the phytoplankton biomass were quite low in all locations.Bacillariophyceae was dominated group(>75.1%for coastal,40.0%for offshore and 43.6%for island stations).In the algal bioassays,the phytoplankton production was stimulated by N availability.The in vivo Chl a values in the+N and+NP treatments were significantly higher than the values in the control and the+P treatments.Based on the field survey,the higher nutrients in coastal waters affected the growth of diatom assemblages,however,little prosperity of phytoplankton was observed in the offshore waters despite the injection of sufficient nutrients in bioassay experiments.The growth of phytoplankton depended on the initial cell density.All of results indicated that a dominant northwestern wind led to a limited nutrients condition at euphotic layers,and the low level of biomass supply from the coasts resulted in low primary production.Both supplying nutrients and introducing phytoplankton through the currents are critical to maintain the high productivity in the Ulleung Basin area of the East Sea. 相似文献
48.
Population Development of the DinoflagellatesCeratium furca andCeratium fusus during Spring and Early Summer in Iwa Harbor, Sagami Bay, Japan 总被引：2，自引：0，他引：2
To examine the population development of the dinoflagellates, Ceratium furca and Ceratium fusus, daily field monitoring was
conducted between April and July 2003 in the temperate coastal water of Sagami Bay, Japan. During the study period, the concentrations
of C. furca were always lower than those of C. fusus. A sharp increase in the densities of both species was recorded on 5
May showing the maximum cell concentrations (C. furca = 14,800 cells L-1, C. fusus = 49,600 cells L-1). In the 7 days prior to the May bloom of the Ceratium species (29 April to 1 May), the highest density of the heterotrophic
dinoflagellate Noctiluca scintillans was observed. Additionally, a second bloom of C. fusus occurred on 22 July. Here, two
causes of the significant increases in the Ceratium populations during the two blooming periods (first time; 1 to 8 May, second
time; 15 to 22 July) are presented. First, an increase in the nutrients of the surface layer regenerated by the breakdown
of blooms by N.scintillans could be considered as a major cause of the population increase of the two Ceratium species. Second,
a decrease in salinity (to 27 psu) was correlated with the later bloom ofC. fusus. These results suggest that the population development of the two Ceratium species requires nutrients regenerated after the
reduction of the diatom population byN. scintillans and, forC. fusus, continuous low salinity conditions, compared to other environmental factors during the rainy season. Key words: Ceratium
furca; Ceratium fusus; Noctiluca scintillans; Bloom process; Environmental factor 相似文献
49.
The SEMAPHORE (Structure des Echanges Mer-Atmosphère, Propriétés Océaniques/ Recherche Expérimentale) experiment, which took place between 04 Oct. and 17 Nov. 1993, was conducted over the oceanic Azores current located in the Azores basin. The SST (Sea Surface Temperature) field was characterized in the SEMAPHORE area (31°–38°N; 21°–28°W) by a large meander with a SST gradient of about 1°C per 100 km. In order to study the evolution of the MABL (Marine Atmospheric Boundary Layer) over the ocean, the mean and the turbulent data were evaluated by the measurement with two aircraft and a ship in different meteorological conditions. Three cases of low pressure and three cases of high pressure are mainly presented here. For the six cases, the satellite images (NOAA) did not show any relation between the SST field and the cloud cover. At each flight level, the decrease of the SST with the altitude due to the divergence of the infrared radiation flux from the ocean is 0.25°C per 100 m. For the comparison between the two aircraft, the mean thermodynamic and dynamic parameters show a good agreement except for the temperature. The dispersion of the sensible heat flux is larger than that of the latent heat flux due to the weak sensible heat flux over the ocean both in the intercomparison between two aircraft and in the comparison between the aircraft and the ship. 相似文献
50.
Antonio Rius Oleguer Nogués-Correig Serni Ribó Estel Cardellach Santi Oliveras Enric Valencia Hyuk Park José Miguel Tarongí Adriano Camps Hans van der Marel Roel van Bree Bas Altena Manuel Martín-Neira 《GPS Solutions》2012,16(2):231-241
The Global Navigation Satellite System Reflectometry (GNSS-R) concept was conceived as a means to densify radar altimeter measurements of the sea surface. Until now, the GNSS-R concept relied on open access to GNSS transmitted codes. Recently, it has been proposed that the ranging capability of the technique for ocean altimetric applications can be improved by using all the signals transmitted in the bandwidth allocated to GNSS, which includes open access as well as encrypted signals. The main objective of this study is to provide experimental proof of this enhancement through a 2-day experiment on the Zeeland Bridge (The Netherlands). In the experiment, we used a custom built GNSS-R system, composed of high gain GPS antennas, calibration subsystem, and an FPGA-based signal processor which implemented the new concepts, an X-band radar altimeter and a local geodetic network. The results obtained indicate that the new approach produces a significant improvement in GNSS-R altimetric performance. 相似文献