• 한국석유지질학회:학술대회논문집
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• spring
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• pp.22-28
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• 1998

Twenty species of calcareous nannofossils belonging to 11 genera are identified from the Seoguipo Formation in Cheju island, Korea. On the basis of the marker species, the Seoguipo Formation is biostratigraphically assigned to the Pseudoemiliania lacunosa Zone (NNl9), which corresponds to the combined zones of Emiliania annula - Emiliania ovata (CN13a-CN14a) of latest Pliocene and Early Pleistocene. Generally, cold-water species is dominant in the lower part, whereas warm-water one in the upper part. This is interpreted the palaeoceanographic condition has changed from cooling to warm phase. The change in floral composition and abundance of specific species allows the recognition of 4 ecostaratigraphic units in the Seoguipo Formation and the migration of oceanographic frontal boundary. According to nannofossil distribution in the study area, the position of an oceanographic boundary between warmer water and cooler water appeared to have oscillated north-south over the Korea Strait and Cheju island in response to glacial and interglacial cycles. The geologic time of the interpreted paleoceanographical changes determined by nannofossil biochronology is well agreed with the results obtained from the Japan Sea (East Sea) and Japan-Sea side of Japan.

• Asian Journal of Atmospheric Environment
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• v.9 no.1
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• pp.78-85
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• 2015

In the past several decades, biofuels have emerged as candidates to help mitigate the issues of global warming, fossil fuel depletion and, in some cases, atmospheric pollution. To date, the only biofuels that have achieved any significant penetration in the global transportation sector are ethanol and biodiesel. The global consumption of biodiesel was rapidly increased from 2005. The goal of this study was to examine the chemical composition on particulate pollutant emissions from a diesel engine operating on several different biodiesels. Tests were performed on non-road diesel engine. Experiments were performed on 5 different fuel blends at 2 different engine loading conditions (50% and 75%). 5 different fuel blends were ultra-low sulfur diesel (ULSD, 100%), soy biodiesel (Blend 20% and Blend 100%) and canola biodiesel (Blend 20% and Blend 100%). The chemical properties of particulate pollutants were characterized using an Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS). Organic matter and nitrate were generally the most abundant aerosol components and exhibited maximum concentration of $1207{\mu}g/m^3$ and $30{\mu}g/m^3$, respectively. On average, the oxidized fragment families ($C_xH_yO_1{^+}$, and $C_xH_yO_z{^+}$) account for ~13% of the three family sum, while ~87% comes from the $C_xH_y{^+}$ family. The two peaks of $C_2H_3O_2$ (m/z 59.01) and $C_3H_7O$ (m/z 59.04) located at approximately m/z 59 could be used to identify atmospheric particulate matter directly to biodiesel exhaust, as distinguished from that created by petroleum diesel in the AMS data.

• 한국석유지질학회:학술대회논문집
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• autumn
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• pp.50-67
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• 1999

Biostratigraphic and paleoenvironmental analyses are carried out on cutting samples from the Dolgorae wells drilled in the Ulleung basin. The clayey, silty, and sandy sediments of the wells yield various microfossil assemblages of relatively good preservation, among which five fossil groups are reported; a total of 97 foraminiferal species of 66 genera, 19 nannofossil species of 12 genera, 86 ostracod species of 41 genera, 107 diatom species of 44 genera, and 124 dinoflagellate cysts species of 45 genera. Based on microfossils the geologic ages of the Dolgorae wells are dated to be from late Early Miocene to Early Pleistocene. Several biohorizons are defined in Neogene successions by the LOD (Last Ocurrence Datum) and FOD (First Ocurrence Datum) of marker species including G. truncatulinoides (LOD: 1.9 Ma) of foraminifera; C. macintyeri (LOD: 1.64-1.60), G. oceanica (FOD: 1.65 Ma), G. caribbeanica (1.72 Ma), D. brouweri (LOD: 2 Ma), R. pseudoumbilica (LOD: 3.66 Ma), P. lacunosa (FOD: 4.2 Ma) of nannofossils; S. ellipsoideus (LOD: 4 Ma), S. palcacantha (LOD: 10.2), C. giusepei (LOD: 14 Ma) of dinocysts; D. seminae v. fossilis (FOD: 3.7 Ma), T. antiqua (LOD: 1.7 Ma), T. convexa (LOD: 2.4 Ma), N. kamtschatica (LOD: 2.58 Ma), T. oestrupii(FOD: 5.1 Ma) of diatoms. Abundance patterns of microfossils throughout the wells reflect changes in paleoenvironmental and sedimentological settings of the basin in relation to sea-level variations. According to these data the large-cycle and small-cycle changes of transgression and regression phases are observed in terrestrial to marine sediments. This high-resolution sequence biostratigraphy established by various fossil groups enabled more reliable correlation between strata and refined interpretation on deposition systems of the basin. It also proved to provide fundamental and precise informations regarding stratigraphic correlation, tectonic events, basin, and depositional history for hydrocarbon explorations, especially in collaboration with seismic-stratigrahic analyses.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.11
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• pp.1515-1520
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• 2012

Insulin-like growth factor binding protein-3 (IGFBP-3) gene is important for regulation of growth and development in mammals. The present investigation was carried out to study DNA polymorphism by PCR-RFLP of IGFBP-3 gene and its effect on fibre traits of Chinese Inner Mongolian cashmere goats. The fibre traits data investigated were cashmere fibre diameter, combed cashmere weight, cashmere fibre length and guard hair length. Four hundred and forty-four animals were used to detect polymorphisms in the hircine IGFBP-3 gene. A 316-bp fragment of the IGFBP-3 gene in exon 2 was amplified and digested with HaeIII restriction enzyme. Three patterns of restriction fragments were observed in the populations. The frequency of AA, AB and BB genotypes was 0.58, 0.33 and 0.09 respectively. The allelic frequency of the A and B allele was 0.75 and 0.25 respectively. Nucleotide sequencing revealed a C>G transition in the exon 2 region of the IGFBP-3 gene resulting in R158G change which caused the polymorphism. Least squares analysis revealed a significant effect of genotypes on cashmere weight (p<0.0001), cashmere fibre length (p<0.001) and hair length (p<0.05) of the animals. The effect of genotypes on cashmere fibre diameter was not statistically significant (p>0.05). The animals of AB and BB genotypes showed higher cashmere weight, cashmere fibre length and hair length than the animals possessing AA genotype. These results suggested that polymorphisms in the hircine IGFBP-3 gene might be a potential molecular marker for cashmere weight in cashmere goats.

• Economic and Environmental Geology
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• v.39 no.1 s.176
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• pp.83-93
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• 2006

The Kita-Yamato Trough is characterized by a SW-NE trending narrow graben between the Yamato Bank and the Kita-Yamato Bank in the central East Sea/Japan Sea (ES/JS). Core 20EEZ-1 was obtained in the flat summit of a small ridge from the southwest Kita-Yamato Trough. The sedimentation was mainly controlled by the supply of hemipelgic sediments and substantial tephras from explosive volcanic eruptions of the Quaternary volcanoes. The aim of this study is to reconstruct the tephrostratigraphy from the marine sediments collected from the Kita-Yamato Trough and to provide the atmosphere and ocean conditions during the explosive volcanic eruptions. According to the detailed tephrostratigraphy and lithofacies records, the core sediments were deposited during the last marine isotope stage (MIS) 7. The core consists of four lithofacies, idetified as, oxidized mud (OM), crudely laminated mud (CLM) and bioturbated mud (BM), interbedded with coarse-grained tephra (TP). The major element geochemistry and stratigraphic positions of seven tephra layers suggest that they originated from the Aira caldera in Kyushu area among the Japanese islands (AT tephra; 29.24 ka), unknown submarine volcano in the south Korea Plateau (SKP-I; MIS 3, SKP-II; MIS 4, SKP-IV; boundary between MIS 6 and MIS 5e, SKP-V; MIS 6, respectively), and the Baegdusan volcano in the Korean Peninsula (B-KY1; ca. 130 ka, B-KY2; ca. 196 ka). The absence of tephras originated trom Ulleung Island in core 20EEZ-l suggest that the tephras had not been transported into the Kita-Yamato Trough by atmosphere conditions during the eruptions. On the other hand, the B-KYI and the B-KY2 tephras derived from the Baegdusan volcano were founded in the Kita-Yamato Trough by a presence of prevailing westerly winds during the eruptions. Furthermore, the SKP tephras were characterized by the transport across the air-water interface, causing quickly thrust of raising eruption plumes from subaqueous explosive eruptions. Surface currents may play an important role in controlling the distribution patterns of the SKP tephras to distal areas. The tephrostratigraphic study in the Kita-Yamato Trough provides the important chronostratigraphic marker horizons and the detailed atmosphere and ocean conditions during the explosive eruptions.