• 한국산업보건학회지
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• 제19권4호
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• pp.381-389
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• 2009

Confined spaces are inherently dangerous workplace and many fatal and nonfatal accidents have been reported. Even though these accidents occur in various kinds of confined spaces, there has rarely been reported on the health hazard agent, i.e., the types of gases and their concentration ranges. Therefore in this study, we evaluated several toxic and asphyxiating gas concentrations in various confined spaces. We surveyed 57 manholes, 3 sewage treatment plants, 2 yellow radish manufacturing companies and 7 barges to measure the concentrations of oxygen($O_2$), hydrogen sulfide($H_2S$), carbon monoxide(CO), ammonia($NH_3$). Lower Explosion Limits(LEL) and Volatile Organic Compounds (VOCs). Those four types of confined spaces occupies 56% of accidents during last 9 years in Korea. In 57 manholes, the concentration varied according to the types of manholes; rainfall and sewage, and by location; residential and industrial areas. Sewage manhole in industrial area was evaluated as the most hazardous than other types of manhole like rainfall manholes, residential sewage manholes. The highest $H_2S$ concentration and the lowest $O_2$ concentration at sewage manhole in industrial area were 300 ppm, 8.7% respectively. In 3 sewage treatment plants, $H_2S$ and $NH_3$ concentrations were reached up to the 500 ppm and 200 ppm respectively. Two yellow radish manufacturing companies showed the concentrations of 316 ppm, 505.2 ppm, 90 ppm and 15.7% for $H_2S$, CO, VOCs and $O_2$, respectively. Seven barges showed 15.9%~20.9% oxygen concentration. Gas species and concentration ranges varied by the types and location of confined spaces; CO, $H_2S$, $O_2$ could be hazardous in manhole, especially manhole connected to sewage plants. CO, $H_2S$, LEL, $O_2$, $NH_3$ should be controlled in sludge silo and sluge pumping confined spaces in sewage treatment plant. The activity of lifting out radish from the storage tank was evaluated more hazardous rather than the other activities in yellow radish manufacturing industry. The employers must conduct the survey to identify all possible confined spaces in their local workplace prior to performing the tasks. At the national level to reduce the accidents in the confined spaces, we suggest that systemic approach and active education program including possible hazards, standard operation procedures, ventilation plan, and personal protective equipment in confined spaces should be implemented.

• Journal of Microbiology and Biotechnology
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• 제15권2호
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• pp.287-295
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• 2005

In order to compare bacteria] community structure and diversity in activated sludges, terminal restriction fragment length polymorphism (T-RFLP) of PCR-amplified 16s rDNAs was analyzed for 31 domestic and industrial wastewater treatment plants (WTPs). Regardless of the characteristics of the wastewaters, the bacteria] community structures of activated sludges appeared diverse and complex. In particular, activated sludges in domestic WTPs contained higher bacterial diversity than those in industrial WTPs. It was also found that terminal restriction fragment (T-RF) profiles derived from domestic WTPs were very similar with each other, although activated sludges were collected from different plants at different locations. Interestingly, activated sludges of a WTP where restaurant and toilet sewages of a company were managed showed a bacterial community structure similar to that of domestic WTPs. Activated sludges in leather industria] WTPs also showed a high similarity. However, other wastewaters possessed different bacterial communities, so that overall similarity was as low as about $30\%$. Since activated sludges from WTPs for domestic wastewaters and a company sewage appeared to hold similar bacterial communities, it was necessary to confirm if similar wastewaters induce a similar bacterial community. To answer this question, analysis of T-RFs for activated sludges, taken from another 12 domestic WTPs, was conducted by using a 6­FAM$^{TM}$-Iabeled primer and an automated DNA sequencer for higher sensitivity. Among 12 samples, it was again found that T-RF profiles of activated sludges from Yongin, Sungnam, Suwon, and Tancheon domestic WTPs in Kyonggi-do were very similar with each other. On the other hand, T-RF profiles of activated sludges from Shihwa and Ansan WTPs were quite different from each other. It was thought that this deviation was caused by wastewaters, since Ansan and Shihwa WTPs receive both domestic and industrial wastewaters. From these results, it was tentatively concluded that similar bacterial communities might be developed in activated sludges, if WTPs treat similar wastewaters.

• 대한환경공학회지
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• 제37권10호
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• pp.590-595
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• 2015

본 연구는 국내 산업단지 폐수종말처리장의 유입수 및 방류수에 존재하는 특정수질유해물질 농도분포 현황을 조사하여 폐수종말처리장으로부터 수계로 배출되는 특정수질유해물질의 효율적인 관리방안을 마련하는 기초자료를 확보하기 위해 수행되었다. 실태조사는 산업단지에 위치하고 실제 처리 및 방류량 기준 $2,000m^3$/일 이상 규모인 27개 폐수종말처리장을 대상으로 진행하였다. 시료채취는 2012년 7~9월에 걸쳐 각 처리장별로 3회(월 1회) 실시하였고, 관리대상 특정수질유해물질 28개 항목 중 22개에 대하여 분석하였다. 산업단지 폐수종말처리장 유입수에서는 수은, 비소, 1,1-디클로로에틸렌, 벤젠 등이 특례지역기준대비 높은 농도로 검출되었고, 방류수에서는 수은, 비소 등이 청정지역기준대비 높은 농도로 검출되었다. 폐수종말처리장의 특정수질유해물질 평균 제거율(상전이 포함)은 셀레늄(30%), 1,4-다이옥산(18%)을 제외하고는 60%이상을 나타냈다.

• 한국약용작물학회지
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• 제12권3호
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• pp.191-202
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• 2004

한국에 분포하고 있는 82종의 약용식물에 대하여 환경내성 및 기능성 소재의 개발을 위한 탐색을 위하여 항산화효소와 관련된 첫 번째 방어기작인 SOD 효소활성과 Phenol 화합물의 함량정도를 검정하여 본 결과 SOD 효소활성은 원지 (P. tenuifolia Willd.), 백편두 (D. lablab L.), 백개자 (S. alba L.), 대황 (R. palmatum L.), 감초 (G. uralensis Fisch), 연자육 (N. nucifera Gaertn), 지황 [R. glutinosa (Gaertner) Liboshitz], 현삼 (S. buergeriana Miq.), 인진 (A. capillaris Thb.)등에서 다른 약용작물보다 비교적 높은 SOD 효소 활성 능력을 나타냈다. Total phenol함량은 $(3{\sim}249.731\;{\mu}g/g)$의 범위를 보였으며 지유(S. officinalis L.), 대황 (R. palmatum L.), 복분자 (R. chingii Hu)에서 각각 $249.731\;{\mu}g/g,\;209.546\;{\mu}g/g,\;170.333\;{\mu}g/g$으로 가장 높은 함량을 나타냈다. 16종의 phenol 화합물의 경우에서는 82종의 약용식물이 각기 매우 상이한 농도의 분포를 나타내었다. 앞으로의 연구에서는, 항산화 효소 및 phenol 화합물이 많이 함유하여 우수한 기능성을 가지고 있는 것을 확인된 약용식물에 대해 그들의 이용성을 증대시킬 수 있는 구체적인 연구가 수행되어져야 할 것으로 사료된다. 또한 phenol성 물질을 많이 함유하는 약용식물 추출물을 이용한 기능성 식품, 화장품, 천연 보존재 및 의약품 등으로 개발 (Cook & Samman, 1996)할 수 있을 것으로 판단되어진다.

• 식물분류학회지
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• 제41권4호
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• pp.415-428
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• 2011

강원도 평창군의 청태산 지역에 자생하는 관속식물상 조사를 2008년 4월부터 2011년 10월까지 총 14회에 걸쳐 실시하였다. 조사 결과, 청태산 지역의 관속식물은 89과 342속 577종 6아종 73변종 7품종 총 663분류군으로 조사되었다. 이 중 19분류군이 한반도 특산식물이었고, 24분류군은 희귀 및 멸종위기식물이었다. 식물구계학적 특정종은 5등급 4분류군, 4등급 16분류군, 3등급 31분류군, 2등급 41분류군 그리고 1등급 44분류군 등 136분류군이 발견되었다. 귀화식물은 37분류군이었으며, 또한 조사된 식물들을 용도별로 구분하면 식용식물 240분류군, 섬유용식물 8분류군, 약용식물 177분류군, 관상용식물 60분류군, 목초용식물 245분류군, 공업용식물 2분류군, 염료용식물 12분류군, 용재용식물 16분류군 등 485분류군이 자원식물로 나타났다.

• Journal of Ecology and Environment
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• 제32권4호
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• pp.267-275
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• 2009

To investigate the possible applications of plants to remediate heavy-metal-contaminated soil, a pilot experiment was performed for four years in a reclaimed dredging area using two Alnus species, i.e., Alnus firma and Alnus hirsuta. In a comparison of phytomass of the two species at two different planting densities, the phytomass of Alnus planted at low density was twice as high as that of Alnus planted at high density after four years. The Alnus species showed active acclimation to the heavy-metal-contaminated soil in a reclaimed dredging area. A. hirsuta showed greater accumulation of phytomass than A. firma, indicating that it is the better candidate for the phytoremediation of heavy-metal-contaminated soils. In the pilot system, Alnus plants took metals up from the soil in the following order; Pb > Zn > Cu > Cr > As > Cd. Uptake rates of heavy metals per individual phytomass was higher for Alnus spp. planted at low density than those planted at high density in the pilot system. Low plant density resulted in higher heavy metal uptake per plant, but the total heavy metal concentration was not different for plants planted at low and high density, suggesting that the plant density effect might not be important with regard to total uptake by plants. The quantity of leached heavy metals below ground was far in excess of that taken up by plants, indicating that an alternative measurement is required for the removal of heavy metals that have leached into ground water and deeper soil. We conclude that Alnus species are potential candidates for phytoremediation of heavy-metal- contaminated surface soil in a reclaimed dredging area.

• Plant Resources
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• 제1권1호
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• pp.53-59
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• 1998

Laboratory experiments for the removal efficiency of heavy metals in land application of sludge, the accumulation and translocation of heavy metals in x plants after transplanting, and the responses of Minari growth with different ratio of land application of sludge were conducted to determine the potential ability of bioremediation with Minari plants. The removal rate and translocation of copper. zinc. lead. and cadmium in soil and plants were compared after transplanting the Minari plants to soil treated with different ratio of sludge. The removal efficiency of heavy metals in soil incorporated with sludge was different with application ratio, but increased with growing periods of Minari plants. The removal efficiency of Cu, Zn, Pb, and Cd ranged from 67 to 74% from 51% to 63%, from 37% to 71%. and from 15% to 25% after 45 days of transplanting. respectively. The amount removed the copper value. 65.9 mg/kg, observed to be highest in soil incorporated 3% sludge after 45 days. The translocation of Cu. Zn. Pb. and Cd from shoots to roots ranged from 18 to 53%, from 17 to 32%, from 14 to 49%, and from 23 to 38% over growing periods. respectively. In plant responses it appeared to be inhibited the plant growth in the treatment compared with the control at early stage of growth. However, the fresh weights of Minari plant increased from 12.5 to 62.5% in the sludge application after 45 days relative to the control. Therefore the Minari might play a useful role in bioremediation of Cu, Zn, Pb, and Cd in the land application of sludge.

• 한국초지조사료학회지
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• 제12권2호
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• pp.85-88
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• 1992

목초의 재생에 따른 칼륨(K)및 마그네슘(Mg)함량의 변화를 알아보기 위해 6가지 목초에 대해 수정액중의 $K_2O$농도를 10 ppm및 300ppm으로 하여 수경재배실험을 수행했다. 약간의 예외가 있었으나 2처리구 모두 예취회수가 늘어갈수록 목초중 칼륨함량이 낮아졌으며, 이러한 경향은 콩과보다 화본과목초에서 두드러졌다.한편 목초중 마그네슘 량은 예취회수가 많아질수록 증가했다. 제 1차 예취때 높은 칼륨함량과 낮은 마그네슘함량으로 인해 K/Mg 함량비가 가장 높았다.6종류의 목초가운데 이탈리안라이그라스의 함량비가 $K_2$O 10ppm처리구에서 가장 낮았으나, 300ppm구에서는 이와 반대로 가장 높았다. 이상의 결과로부터 다른 예취때보다 제 1차 예취때에 목초중 칼륨함량은 높고 마그네슘함량은 낮게 된다는 것과 온도가 급격하게 올라갈 때는 소량의 칼륨비료질 사용과 다량시용 사이에 K/Mg 함량비에 큰 차이가 생길 수 있음을 알았다.음을 알았다.

• The Plant Pathology Journal
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• 제38권6호
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• pp.583-592
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• 2022

Root-knot nematode disease is a widespread and catastrophic disease of tobacco. However, little is known about the relationship between rhizosphere bacterial community and root-knot nematode disease. This study used 16S rRNA gene sequencing and PICRUSt to assess bacterial community structure and function changes in rhizosphere soil from Meloidogyne incognita-infected tobacco plants. We studied the rhizosphere bacterial community structure of M. incognita-infected and uninfected tobacco plants through a paired comparison design in two regions of tobacco planting area, Yuxi and Jiuxiang of Yunnan Province, southwest China. According to the findings, M. incognita infection can alter the bacterial population in the soil. Uninfested soil has more operational taxonomic unit numbers and richness than infested soil. Principal Coordinate Analysis revealed clear separations between bacterial communities from infested and uninfested soil, indicating that different infection conditions resulted in significantly different bacterial community structures in soils. Firmicutes was prevalent in infested soil, but Chloroflexi and Acidobacteria were prevalent in uninfested soil. Sphingomonas, Streptomyces, and Bradyrhizobium were the dominant bacteria genera, and their abundance were higher in infested soil. By PICRUSt analysis, some metabolism-related functions and signal transduction functions of the rhizosphere bacterial community in the M. incognita infection-tobacco plants had a higher relative abundance than those uninfected. As a result, rhizosphere soils from tobacco plants infected with M. incognita showed considerable bacterial community structure and function alterations.

• 한국환경과학회지
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• 제31권3호
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• pp.247-254
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• 2022

This study investigated the effect of vegetation mat on plant growth and salt reduction in the soil treated with high concentration deicing salt. In order to measure soil chemical characteristics and plant growth, three native groundcover plants (Dendranthema zawadskii var. latilobum, Dendranthema boreale, and Kalimeris yomena) were grown in each of the three plastic containers (50.0 cm width × 35.0 cm length × 8.5 cm deep) with a high concentration treatment of calcium chloride deicing salt. There were two treatments: control, and BVM that combines B (blanket) and VM (vegetation mat). 1,600 g of soil was placed on the top of the drainage layer with 290 g of perlite, 100 seeds each of the three native plants with three repetitions were sowed, and 10 g/L of calcium chloride deicing salt was added in the treatment. As a result of the chemical properties of soil, soil in control treatment was acidic and soil electrical conductivity in BVM was the lowest. Also, exchangeable cations (K⁺, Ca²⁺, Na⁺, and Mg²⁺) in soil and all the three plants were significantly decreased in the BVM treatment. Meanwhile, the germination rate of Dendranthema zawadskii var. latilobum was the highest under high concentration deicing salt in compared to the two plants. Overall, three native groundcover plant growth was higher in the BVM than control treatment significantly. These results suggest that the treatment of blanket vegetation mat has a positive effect on soil and plant growth in soil damaged by deicing salt.