• 한국지하수토양환경학회지:지하수토양환경
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• 제13권4호
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• pp.8-21
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• 2008

지질 매체의 층상 불균질성과 지하수 양수 방식이 해안 대수층 내에서의 지하수 유동과 염분 이동에 미치는 영향을 정량적으로 분석하기 위하여 수리동역학적 분산 수치 모델을 이용한 일련의 삼차원 수치 모델링이 수행되었다. 해수 침투에 대한 층상 불균질성의 영향을 평가하기 위하여 하부 사토층(대수층)과 상부 점토층(준대수층)으로 구성된 층상 불균질 해안 대수층과 이에 상응하는 등가의 물질로 구성된 균질 해안 대수층을 수치 모델링하였다. 또한 해수 침투에 대한 지하수 양수 방식의 영향을 평가하기 위하여 전체 수치 모델링 기간 동안에 동일한 양의 지하수를 양수하는 연속적인 지하수 양수 방식과 두 개의 주기적인 지하수 양수 방식을 상기한 두 해안 대수층에 적용하였다. 수치 모델링 결과는 주기적인 지하수 양수 방식이 층상 대수층의 하부 사토층뿐만 아니라 상부 점토층에서의 지하수 유동과 염분 이동에 보다 중대한 악영향을 끼치며, 주기적인 지하수 양수 시에 양수 강도가 클수록 지하수 염수화가 공간적 및 시간적으로 더욱 심화됨을 보여준다. 이는 해수 침투에 의한 지하수 염수화를 최소화하기 위해서는 지속적인 지하수 양수 방식이 보다 더 적합할 수 있음을 의미한다. 또한 수치 모델링 결과는 주기적인 지하수 양수시에 상부 점토층에서의 지하수 염수화 양상이 하부 사토층에서의 그것에 비해 매우 다르게 발생함을 보여준다. 이러한 두 지층 사이의 지하수 염수화 양상의 차이는 층상 해안 대수층의 층상 불균질성에 기인하는 것으로 해석된다.

• 한국양식학회지
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• 제13권4호
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• pp.317-323
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• 2000

숭어 치어의 담수 사육을 위한 저염분 순화방법과 이에 따른 적응 능력을 높이기 위하여 염분사료를 공급하여 이에 따른 성장, 생존율 및 어체의 생리상태를 비염분사료구와 비교하였다. 실험 종료시 전장과 체중의 성장률은 해수사육구(SWN), 순차적으로 담수로 옮긴 염분사료구(GFWS) 및 순차적으로 담수로 옮긴 비염분사료구(GFWN)에서 빠르게 담수로 옮긴 염분사료구(FWS) 및 빠르게 담수로 옮긴 비염분사료구(FWN) 순서로 나타났다. 비만도는 모든 실험구에서 서로 차이를 보이지 않았다. 실험어의 생존율은 순차적으로 담수로 옮긴 염분사료구가 92.2${\pm}$2.2%로 가장 높았으나, 다른 실험구와 차이가 없었다. 어체의 수분함량은 빠르게 담수로 옮긴 비염분사료구에서 해수구보다 높게 나타나 차이를 보였다. 체액의 삼투질 농도는 실험 종료시에 모든 실험구에서 차이를 보이지 않았다. $Na^+$ 농도는 실험 종료시 해수사육구, 순차적으로 담수로 옮긴 비염분사료구, 순차적으로 담수로 옮긴 염분사료구 및 빠르게 담수로 옮긴 비염분사료구에서 차이를 보이지 않았다. 체액의 K/$^+$ 농도는 실험 종료시 해수사육구가 다른 실험구에 비교해 높은 수준을 나타냈다.

• 터널과지하공간
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• 제20권5호
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• pp.378-389
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• 2010

해저에 시공되는 터널은 일반시공보다 환경에 더 많은 영향을 받는다. 특히 해수의 침입에 따른 염해의 위험에 노출되어 있으며, 이는 콘크리트에 포함된 철근과 강섬유의 부식에 큰 영향을 미친다. 해수 침투에 따른 염해 가능성이 염려되는 터널에서 최근 내부식성 섬유로 그 활용도가 증가하고 있는 폴리프로필렌섬유를 대상으로 강섬유와의 성능 비교를 통하여 적정 배합비를 결정하고, 원형패널 시험과 휨인성 시험을 통해 지보재로서의 성능을 평가하였다. 본 연구의 결과는 해저에 시공되는 터널에서 섬유보강재의 선택 및 섬유보강 숏크리트 설계에 활용될 수 있을 것으로 판단된다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.499-502
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• 2004

Groundwater chemistry in a coastal region having complex contaminant sources was investigated. Water analysis data for 197 groundwater samples collected from the uniformly distributed sixty-six wells were used. Chemical analysis rand results indicate that groundwaters show wide concentration ranges in major inorganic ions, reflecting complex hydrochemical processes of pollutants. Due to the complexity of groundwater chemistry, Results illustrate that thirty five percent of the wells do not fit for drinking based on nitrate and chloride concentration in the study area. the samples were classified into four groups based on Cl and NO$_3$ concentrations and the processes controlling water chemistry were evaluated based on the reaction stoichiometry. The results explained the importance of mineral weathering, anthropogenic activities (nitrification and oxidation of organic matters), and Cl-salt inputs (seawater, deicer, NaCl, etc.) on groundwater chemistry. It was revealed that mineral dissolution is the major process controlling the water chemistry of the low Cl and NO$_3$ group (Group 1). Groundwaters high in NO$_3$ (Groups 2 and 4) are acidic in nature, and their chemistry is largely influenced by nitrification, oxidation of organic matters and mineral dissolution. In the case of chloride rich waters (Group 3), groundwater chemistry is highly influenced by mineral weathering and seawater intrusion associated with cation-exchange reactions.

• 한국환경보건학회지
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• 제29권2호
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• pp.94-102
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• 2003

This study was carried out to investigated the distribution and characteristics of Vibrio spp. isolated from fish and shellfish, seawater and brackish water samples collected from Pohang, Uljin, Yeongduk and Gyeongju in Gyeongbuk Province from April 2000 to October 2000. Total 155 strains of genus Vibrio were isolated from 439 collected samples, and numbers of isolated strains of V. parahaemolyticus and V. vulnificus were 140 and 15, respectively. The isolation rate from the samples collected in Pohang was the highest as 41.5% (76 strains), and wat the highest as 71.4% (30 strains) in brackish water, and was the highest as 55.7% (34 strains) in August. And the optimal pH, temperature, and NaCl concentration for growth of V. parahaemolyticus and V. cholerae were 8.0, 3$0^{\circ}C$ and 2.0％, respectively. In a resistance test for environmental factors, heat and cold resistants of V. parahaemolyticus were higher than those of V. vulnificus, withstanding for 15 minutes at 6$0^{\circ}C$ and 6 days at -18$^{\circ}C$. The pH range for existence of V. parahaemolyticus and V. vulnificus were 4.5~l1.0 and 4.5~10.0, showing the similar resistance to pH. V. parahaemolyticus and V. vulnificus could grow in media containing up to 10.0% and 7.0% NaCl, respectively, Salt-tolerance of V. parahaemolyticus was higher than that of V. vulnificus. In an antibiotics sensitivity test against 16 strains of V. parahaemolyticus, twelve strains were resistant to ampicillin, eight strains were resistant to cephalothin. one strain was resistant to streptomycin, and one strain was resistant to ticarcillin.

• Journal of Microbiology and Biotechnology
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• 제26권11호
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• pp.1891-1907
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• 2016

Yeasts that are present in marine environments have evolved to survive hostile environments that are characterized by high exogenous salt content, high concentrations of inhibitory compounds, and low soluble carbon and nitrogen levels. Therefore, yeasts isolated from marine environments could have interesting characteristics for industrial applications. However, the application of marine yeast in research or industry is currently very limited owing to the lack of a suitable isolation method. Current methods for isolation suffer from fungal interference and/or low number of yeast isolates. In this paper, an efficient and non-laborious isolation method has been developed and successfully isolated large numbers of yeasts without bacterial or fungal growth. The new method includes a three-cycle enrichment step followed by an isolation step and a confirmation step. Using this method, 116 marine yeast strains were isolated from 14 marine samples collected in the UK, Egypt, and the USA. These strains were further evaluated for the utilization of fermentable sugars (glucose, xylose, mannitol, and galactose) using a phenotypic microarray assay. Seventeen strains with higher sugar utilization capacity than the reference terrestrial yeast Saccharomyces cerevisiae NCYC 2592 were selected for identification by sequencing of the ITS and D1/D2 domains. These strains belonged to six species: S. cerevisiae, Candida tropicalis, Candida viswanathii, Wickerhamomyces anomalus, Candida glabrata, and Pichia kudriavzevii. The ability of these strains for improved sugar utilization using seawater-based media was confirmed and, therefore, they could potentially be utilized in fermentations using marine biomass in seawater media, particularly for the production of bioethanol and other biochemical products.

• Conservation and Restoration of Cultural Heritage
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• 제1권1호
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• pp.29-37
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• 2012

The West Stone Pagoda at Gameunsaji Temple Site constructed in the 7th century is mainly composed of dark grey dacitic tuff bearing small numerous dioritic xenoliths. These xenoliths resulted in small holes due to differential weathering process from the host rocks. Physical strength of the pagoda was decreased due to weathering and damage caused by petrological, biological and coastal environmental factors. The southeastern part of the pagoda was extremely deteriorated that the rock surface showed exfoliation, fracture, open cavity, granular decomposition of minerals and salt crystallization by seawater spray from the eastern coast. The stone blocks were intersected by numerous cracks and contaminated by subsequent material such as cement mortar and iron plates. Also, the pagoda was colonized by algae, fungi, lichen and bryophytes on the roof rock surface and the gaps between the blocks. As a result of ultrasonic test, the rock materials fell under Highly Weathered Grade (HW) or Completely Weathered Grade (CW). Thus, conservational intervention is essentially required to prevent further weakening of the rock materials.

• 한국환경과학회지
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• 제29권4호
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• pp.383-393
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• 2020

To increase electrolysis performance, the applicability of seawater to the iron-fed electro-Fenton process was considered. Three kinds of graphite electrodes (activated carbon fiber-ACF, carbon felt, graphite) and dimensionally stable anode (DSA) electrode were used to select a cathode having excellent hydrogen peroxide generation and organic decomposition ability. The concentration of hydrogen peroxide produced by ACF was 11.2 mg/L and those of DSA, graphite, and carbon felt cathodes were 12.9 ~ 13.9 mg/L. In consideration of durability, the DSA electrode was selected as the cathode. The optimum current density was found to be 0.11 A/㎠, the optimal Fe²⁺ dose was 10 mg/L, and the optimal ratio of Fe²⁺ dose and hydrogen peroxide was determined to be 1:1. The optimum air supply for hydrogen peroxide production and Rhodamine B (RhB) degradation was determined to be 1 L/min. The electro-Fenton process of adding iron salt to the electrolysis reaction may be shown to be more advantageous for RhB degradation than when using iron electrode to produce hydrogen peroxide and iron ion, or electro-Fenton reaction with DSA electrode after generating iron ions using an iron electrode.

• 한국가축번식학회지
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• 제16권4호
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• pp.363-376
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• 1993

This study was taken to examine serum components concentrations and electrophoretic patterns of female tilapia(Oreochromis niloticus) living in 0$\textperthousand$, 10$\textperthousand$, 20$\textperthousand$, and 30$\textperthousand$ salt concentrations, respectively. The results obtained in these experiments were summarized as follows. The level of albumin and total protein showed changes in each salinity, but didn't significantly(P<0.05) change in Oreochromis niloticus. The level of BUN didn't significantly(P<0.05) change. When fish were adapted from 0$\textperthousand$ to 10$\textperthousand$, 20$\textperthousand$ and 30$\textperthousand$, each calcium level in every salinity groups showed less than that of control, and didn't significantly change in 10$\textperthousand$, 20$\textperthousand$, 30$\textperthousand$ salinity. The level of calcium didn't significantly(P<0.05) change in each salinity. In 20$\textperthousand$ salinity, the level of cholesterol was at the highest peak. When fish were adapted from 0$\textperthousand$ to 10$\textperthousand$, 20$\textperthousand$ and 30$\textperthousand$, each glucose level gradually decreased. When fish were adapted from 0$\textperthousand$ to 10$\textperthousand$, 20$\textperthousand$ and 30$\textperthousand$, each glucose level gradually decreased. When fish were adapted from 0$\textperthousand$ to 10$\textperthousand$, 20$\textperthousand$ and 30$\textperthousand$. In 30$\textperthousand$ salinity, the level of alkaline phosphatase was at the highest peak. The level of serum enzyme such as SGOT and SGPT was higher in seawater-adapted group than in freshwater group. The level of phosphorus chnage significantly(P<0.05) in each salinity. Correlation coefficient between serum albumin and glucose in 0$\textperthousand$ was ＋0.924. Correlation coefficient between serum SGOT and SGPT of individuals in 0$\textperthousand$ was ＋0.917. Fraction 1 of transferrin patterns of tilapia(Oreochromis niloticus) adapted in seawater was much thicker than that of transferrin patterns of individuals adapted in freshwater. Also fraction No. a wasn't observed in some individuals adapted in freshwater. These results showed that transferrin adapted in seawater relatively increased. Slight differences, that is, showed to be observed in total iron binding capacityand iron saturatin rate between tilapia adapted in freshwater and in seawater. The increase in total iron binding capacity was attributed to a rise in transferrin pressent in the first fraction of serum protein adapted in seawater. Accordingly, the serum iron levles seemed to be related to salinity($\textperthousand$).

• 한국식생활문화학회지
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• 제34권2호
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• pp.129-141
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• 2019

The modernization process of Korea, which can be considered westernization, has influenced Korean folk culture. In this process the kimchi culture could be destroyed. However the kimchi culture has survived very well to date. This study was conducted to investigate the cause of this survival of the kimchi culture. To accomplish this, the enormous influence of modernization on kimchi culture and the cause of its successful survival was investigated in the middle region of the Korean peninsula. We think that the kimchi culture can survive because of the inherent system and structure. Kimchi is composed of vegetables, salt, seasoning, and salted seafood (jeotgal), which are systemized. We also described the kimchi ethnography in this region to study the regional characteristics. The eastern coast uses a different method to salt the cabbage during the production of Kimchi, namely it uses seawater to accomplish this. Additionally, pollak broth is used instead of jeotgal. However nowadays the regional uniqueness of kimchi culture has greatly disappeared in large part, and Korean kimchi is standardized in this region.