• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.86-90
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• 2002

Cooling water sampled at Pohang Steel Company, Korea, was used to study the effect of biocide (NaOCl) on biofilm formation and metal corrosion. Planktonic microorganisms were killed in the presence of biocide (0.2％ NaOCl) within 1.5 h, but not sessile microorganisms in biofilms even after one week. Black color of biofilms, possibly due to the activity of sulfate reducing bacteria, were made with the natural cooling waters, while orange color of biofilms were formed when cooling waters were autoclaved or when 0.2％ NaOCl was added to the natural cooling waters. Microbially influenced corrosion rate in black color of biofilms was 2.3 fold higher than that in orange color of biofilms.

• Economic and Environmental Geology
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• v.31 no.3
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• pp.265-271
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• 1998

In the hydrologic and hydrochemical studies of natural waters, oxygen and hydrogen isotope compositions of waters are very important to elucidate the origin and circulation pattern of water in the hydrologic system. The hydrogen isotope analysis of waters usually has been undertaken through the reduction of water to form hydrogen gas using pure metals (in general, zinc and uranium). In 1996, a new apparatus (H/Device) was developed to prepare the water samples (by the reduction with Cr metal) without some intrinsic problems that may yield incorrect and/or inaccurate data, and was installed at 1997 in the Center for Mineral Resources Research (CMR) in Korea University. However, the optimistic conditions of preparation and analysis of samples has not been established. In this paper, we introduce the efficiency of H/Device to obtain accurate hydrogen isotope values of water, and discuss both the optimum conditions including the effective reduction time and the probable mixing (memory) effect between successive samples. We obtained large amounts of a laboratory working standard (KUW; Korea University Water) with the average ${\delta}D_{SMOW}$ value of $-42.1{\pm}1.0$‰ $(1{\sigma})$.

• Animal Systematics, Evolution and Diversity
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• v.26 no.3
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• pp.353-356
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• 2010

Two species in two genera of the family Salpidae were identified in Korean waters: Ihlea punctata (Forskal, 1775) and Salpa fusiformis Cuvier, 1804. I. punctata is a newly reported species in Korean fauna, while S. fusiformis is redescribed with unrecorded solitary zooid stage.

• Animal Systematics, Evolution and Diversity
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• v.25 no.2
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• pp.197-199
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• 2009

The alpheid shrimps collected from Jejudo Island turned out to be a species belonging to the genus Prionalpheus which is an unreported genus from Korean waters. In this paper, Prionalpheus sulu is reported for the first time from Korean waters with description and illustration.

• Animal Systematics, Evolution and Diversity
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• v.26 no.2
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• pp.161-163
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• 2010

One species of the family Salpidae in Korean waters, Iasis zonaria (Pallas, 1774), was identified and redescribed. This species is newly added in the Korean fauna.

• Animal Systematics, Evolution and Diversity
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• v.34 no.3
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• pp.152-158
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• 2018

Two new records of spionid polychaetes, Prionospio pulchra Imajima, 1990 and Scolelepis (Scolelepis) sagittaria Imajima, 1992, collected from Korean waters are reported here with detailed descriptions and illustrations. Prionospio pulchra can be distinguished from its relatives by remarkably long and apinnate branchiae, the first chaetiger with notopodial chaetae, and the presence of ventral sabre chaetae. Scolelepis (Scolelepis) sagittaria is characterized by a sagittate prostomium, an occipital tentacle, and bi- or tridentate hooded hooks. In this paper, photographs of scanning electron microscopy for characteristic features of each species are presented. Keys to Prionospio and Scolelepis species from Korean waters are also provided.

• Journal of environmental and Sanitary engineering
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• v.15 no.1
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• pp.88-94
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• 2000

The purpose of this study was to analyze and compare the contents of minerals and ionic components in domestic commercial natural mineral waters, and to investigate the relationship between water quality and characteristics of suspended and rocks there of its source. All mineral waters tested in this study met the korean mineral water quality guideline, although chemical components varied widely depending upon the geological characteristics and degree of urbanization of the source area or physical water treatment method. The water quality of commercial bottled water was different from that of source water, especially in cationic components, and showed a tendency to become worse with time elapsed. The water quality on the bottle was also different from the measured quality.

• Animal Systematics, Evolution and Diversity
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• v.30 no.4
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• pp.323-326
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• 2014

Colonial ascidian, Eusynstyela monotestis (Tokioka, 1953), is newly reported from Korean waters. The specimens of E. monotestis examined in this study were collected at subtidal zone of Beomseom, Munseom, Seopseom and Chagwido in Jeju-do by SCUBA diving. The genus Eusynstyela Michaelsen, 1904 is also new to Korean waters and it is distinct from other genera by having branchial sac with folds, longitudinal stigmata, hermaphrodite gonads on both sides, 1-2 male follicles in each gonad and body wall with endocarps. Eusynstyela monotestis is distinct from other species by having gonad with only single male follicle. In this paper, detailed descriptions and photographs of Eusynstyela monotestis (Tokioka, 1953) are provided.

• Animal Systematics, Evolution and Diversity
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• v.31 no.1
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• pp.1-7
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• 2015

Colonial ascidians, Clavelina elegans (Oka, 1927) and Clavelina miniata Watanabe & Tokioka, 1973 are reported for the first time in Korean waters. As a result of this study, three species of the genus Clavelina are now recorded in Korean fauna. Clavelina elegans and C. miniata have been reported only from Japan. We expanded the distribution range of these species to Korea. The specimens of C. elegans and C. miniata were collected from the subtidal zone of Beomseom and Chagwido in Jeju-do by SCUBA diving. Detailed descriptions, illustrations and photographs of these species are provided in this paper.

• Journal of Species Research
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• v.9 no.2
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• pp.131-146
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• 2020

Siphonophores are unique, gelatinous zooplankton, which many individuals gather and live like one "Superorganism". The role of individuals in the colony differs greatly depending on their morphological difference, making them more unique. In this study, we report four species belonging to Diphyidae Quoy and Gaimard, 1827 sampled from the South Sea and off Jeju Island, Korea. Two Chelophyes Totton, 1932 (C. appendiculata (Eschscholtz, 1829); C. contorta (Lens and van Riemsdijk, 1908)) and two Eudoxoides Huxley, 1859 (E. mitra (Huxley, 1859); E. spiralis (Bigelow, 1911)) species are described with multi-focus stacked digital images. Our findings update the confirmed order Siphonophorae Eschscholtz, 1829 in Korea to be three suborders, five families, eight genera, and 13 species. In addition, we summarize the synonyms and global distributions of these four newly recorded species in Korean waters.