• Title/Summary/Keyword: Water sampling

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Bactericidal Effect of Waterless Alcohol Gel Hand Washing Agent (물 없이 사용하는 알코올 젤의 손소독 효과에 관한 연구)

  • Jeong, Jae-Sim;Kim, Duck-Hee;Kim, Mi-Na;Choe, Myoung-Ae
    • Journal of Korean Biological Nursing Science
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    • v.4 no.2
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    • pp.127-137
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    • 2002
  • The purpose of this study was to compare the hand disinfection effect of waterless alcohol gel hand washing agent with that of soap and water, 4% chlorhexidine gluconate, and 10% povidone-iodine. Hands of fourty subjects were artificially contaminated with Acinetobacter baumannii $5m{\ell}$ and randomly distributed to each hand washing methods. Samples were collected from gloved hand by glove juice sampling procedure. Mean log reduction after hand washing were compared with baseline values. Number of microorganisms were converted to log and tested by ANOVA in SPSSWIN 10.0. Mean log reduction of soap and water, alcohol gel, 4% chlorhexidine gluconate, 10% povidone-iodine were $2.76{\pm}0.62$, $2.97{\pm}0.56$, $4.66{\pm}1.70$, $4.60{\pm}0.91$, respectively. The bactericidal effect of alcohol gel was similar to that of soap and water, but the effect was much less than chlorhexidine gluconate and povidone-iodine(p<0.001). In terms of microorganism reduction, the efficacy of waterless alcohol gel was almost the same as soap and water hand washing. Further evaluation of the bactericidal effect of waterless alcohol gel is needed because waterless alcohol gel is simple, convenient, and non-irritating hand washing agent and also very effective in busy hospital environment.

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Transformation of dissolved organic matter in a constructed wetland: A molecular-level composition analysis using pyrolysis-gas chromatography mass spectrometry

  • Park, Jongkwan;Choi, Mijin;Cho, Jaeweon;Chon, Kyongmi
    • Environmental Engineering Research
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    • v.23 no.4
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    • pp.390-396
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    • 2018
  • This study investigated the transformation of dissolved organic matter (DOM) in a free-water surface flow constructed wetland. Pyrolysis gas chromatography-mass spectrometry (Py-GC/MS) coupled with preparative high-performance liquid chromatography (prep-HPLC) was used to analyze the compositions of biopolymers (polysaccharides, amino sugars, proteins, polyhydroxy aromatics, lipids and lignin) in DOM according to the molecular size at three sampling points of the water flow: inflow, midflow, and outflow. The prep-HPLC results verified the decomposition of DOM through the decrease in the number of peaks from three to one in the chromatograms of the sampling points. The Py-GC/MS results for the degradable peaks indicated that biopolymers relating to polysaccharides and proteins gradually biodegraded with the water flow. On the other hand, the recalcitrant organic fraction (the remaining peak) in the outflow showed a relatively high concentration of aromatic compounds. Therefore, the ecological processes in the constructed wetland caused DOM to become more aromatic and homogeneous. This indicated that the constructed wetland can be an effective buffer area for releasing biochemically stable DOM, which has less influence on biological water quality indicators, e.g., biochemical oxygen demand, into an aquatic ecosystem.

The Effects of the Exercise Commitment of University Water Sport Participants on Leisure Satisfaction.

  • Hur, Seung Eun;OH, Yun Chae;SONG, Youn Sang;MOON, Hwang Woon
    • Journal of Sport and Applied Science
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    • v.3 no.2
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    • pp.1-10
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    • 2019
  • Purpose: With an increase of concerns towards leisure activities, water sport participation is constantly increasing. The purpose of this study is to examine the effects of exercise commitment on leisure satisfaction. Research design, data, and methodology: To accomplish the purpose, the study collected data from undergraduate students who participated water sports class in University. The sample was extracted by purposive sampling of nonprobability sampling. 281 students participated in the survey. Data were computed via correlation test, factor analysis, Cronbach's α test, one way ANOVA, and regression. Significance of all results was set to p<.05. Results: The results are like below. Frist, in terms of differences by demographics, the results indicated that significant difference between exercise commitment and leisure satisfaction by gender was shown only in psychological factor in leisure satisfaction. Second, in terms of the relationship between commitment and satisfaction, the findings pointed out that significant difference between exercise commitment and leisure satisfaction by grade was observed only in leisure satisfaction, especially on the educational part. Third, the study revealed that no significant difference by participation level was shown. Conclusions: In conclusion, the study posits that exercise commitment play a function in increasing the leisure satisfaction. Further implications were discussed.

A Review on the Application of Stable Water Vapor Isotope Data to the Water Cycle Interpretation (수증기안정동위원소의 물순환 해석에의 적용에 대한 고찰)

  • Lee, Jeonghoon;Han, Yeongcheol;Koh, Dong-Chan;Kim, Songyi;Na, Un-Sung
    • Journal of Soil and Groundwater Environment
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    • v.20 no.3
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    • pp.34-40
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    • 2015
  • Studies using stable water vapor isotopes have been recently conducted over the past two decades because of difficulties in analysis and sample collection in the past. Stable water vapor isotope data provide information of the moisture transport from ocean to continent, which are also used to validate an isotope enabled general circulation model for paleoclimate reconstructions. The isotopic compositions of groundwater and water vapor also provide a clue to how moisture moves from soil to atmosphere by evapotranspiration. International Atomic Energy Agency designates the stations over the world to observe the water vapor isotopes. To analyze the water vapor isotopes, a cryogenic sampling method has been used over the past two decades. Recently, two types of laser-based spectroscopy have been developed and remotely sensed data from satellites have the global coverage. In this review, measurements of isotopic compositions of water vapor will be introduced and some studies using the water vapor isotopes will also be introduced. Finally, we will suggest the future study in Korea.

Occurrence of Organophosphorus Flame Retardants (OPFRs) in Nakdong River Basin : Mainstreams, Tributaries and STP Effluents (낙동강 수계에서의 유기인계 난연제류 검출 현황 : 본류, 지류 및 하수처리장 방류수)

  • Seo, Chang-Dong;Son, Hee-Jong;Choi, Jin-Taek;Ryu, Dong-Choon;Yoo, Pyung-Jong
    • Journal of Korean Society of Environmental Engineers
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    • v.37 no.7
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    • pp.396-403
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    • 2015
  • This study was investigated occurrence and distribution patterns of organophosphorus flame retardants (OPFRs) in Nakdong River basin (mainstream, tributaries and sewage treatment plant (STP) effluents). 3 (TCEP, TCPP and TBEP) out of 9 OPFRs were detected in 6 out of 20 sampling sites (mainstream and tributaries), The TCPP and TBEP concentration levels in mainstream samples were ND~114.9 ng/L ng/L and ND~49.1 ng/L, respectively. And the TCEP, TCPP and TBEP concentration levels in tributary samples were ND~1,865.3 ng/L, ND~519.2 ng/L and ND~210.4 ng/L, respectively. 4 (TBP, TCEP, TCPP and TBEP) out of 9 OPFRs were detected in effluents of 11 STPs around the Nakdong River basin. The TBP, TCEP, TCPP and TBEP concentration levels in 11 STP effluents were ND~458.5 ng/L, ND~2,932.7 ng/L, ND~1,320.7 ng/L and ND~655.2 ng/L, respectively. According to the sampling season, change ranges of distribution patterns and detected concentrations of OPFRs were highly variable in the same sampling sites.

Comparison of sampling method of phytoplankton for type approval of ballast water management system (선박평형수처리장치 형식승인을 위한 식물플랑크톤 샘플링 방법 비교)

  • Jang, Pung-Guk;Hyun, Bonggil;Lee, Woo-Jin;Choi, Keun-Hyung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.12
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    • pp.426-433
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    • 2020
  • This study aimed to compare the pretreatment methods of phytoplankton for type approval of the Ballast Water Treatment System (BWMS). The International Maritime Organization (IMO) and the United States Maritime Police (USCG) use two different test methods for this purpose. To compare the two methods, a test for concentration and non-concentration was performed with cultured and natural phytoplankton, and samples from the land-based BWMS test. The extent of damages caused by the process of concentration varied between cultured and natural species, indicating differences depending on the physiological and morphological characteristics of the species. In the land-based test, in the control water with a high biological population, the number of non-concentrated samples was about twice as high as that of the concentrated samples. There was no distinct difference between the two methods in the treated water with a low biological population. Thus, although there is a difference between concentration and non-concentration for phytoplankton sampling, the concentration method can be applied as a method of evaluating BWMS performance. However, a method for evaluating whether live species in treated water may be lost or damaged during the concentration process of sampling should be developed and validated.

Development of DNA-Based Assessment Method for Mold in Floor Dust of Dwellings in Korea (바닥 먼지내에서 DNA 기반 곰팡이 분석기법 개발)

  • Lee, Jeong-Sub;Kim, Sung Yeon;Choi, Kil Yong;Ryu, Jungmin;Hwang, Eun Seol;Lee, Juyeong;Kwon, Myunghee;Chung, Hyenmi;Seo, SungChul
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.27 no.4
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    • pp.324-332
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    • 2017
  • Objectives: Much scientific evidence indicate a positive association between moldy environments and respiratory illnesses and/or symptoms. However, few comprehensive assessments of mold have been performed for such settings. Spore counts or microscopic enumeration only may not be sufficient for evaluating fungal exposure. Recently, Mold Specific QPCR technology developed by the US EPA (Environmental Relative Moldiness Index, ERMI) has been widely used worldwide and great performance for assessing fungal exposure has been shown. Methods: We aimed to develop a Korean version of ERMI suitable for the distribution of fungal flora in Korea. Thirty dwellings in the Seoul and Incheon area were selected for sampling, and each was classified as 'Flooded, 'Water-damaged' or 'Non-water-damaged'. Results: Dust on the floor and airborne sampling were collected using an MAS100 and a 'Dustream' collector. Samples were analyzed by quantitative polymerase chain reaction(QPCR) for the 36 molds belonging to ERMI. Student t-test and ANOVA tests were carried out using SAS software. The median ERMI values of flooded, water damaged, and non-water damaged dwellings were 8.24(range: -5.6 to 27.9), 5.47(-25. 4 to 32.7), and -15.30(-24.6 to 14.8), respectively. Significant differences were observed between flooded and non-water damaged dwellings (P=0.001) and between water-damaged and non-water damaged dwellings (P=0.032). Conclusion: Our findings indicate that ERMI values attributed to dust samples in Korea could be applicable for the identification of flooded or water damaged buildings. However, much data is needed for continuously developing the Korean version of ERMI values.

Characteristics and Combined Sewer Overflows (합류식 하수관거의 유출 특성 분석 조사)

  • An, Ki-Sun;Jang, Sung-Ryong;Kwon, Young-Ho
    • Journal of Environmental Science International
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    • v.19 no.6
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    • pp.747-753
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    • 2010
  • It follows in quality and sewage exclusion method of the investigation objective sector and the Combined Sewer Overflows which is suitable in regional characteristics and the confluence area against the rainfall initially a flow and the medulla and measurement - it analyzes the initial rainfall outflow possibility control plan which is suitable in the domestic actual condition and it proposes the monitor ring plan for the long-term flow and pollution load data accumulation. From the research which it sees the Infiltration water/Influent water and CSOs investigation it passes by the phase of hazard chain and Namwon right time 4 it does not hold reverse under selecting, Measurement it used the hazard automatic flow joint seal Sigma 910 machine and in case 15 minute interval of the I/I, it measured a flow at case 5, 15 minute standing of the CSOs. The water quality investigation for the water leakage investigation of the I/I and the sewage from the point which is identical with flow measurement during on-the-spot inspection duration against 6 items which include the BOD sampling and an analysis, when the rainfall analysis for CSOs fundamental investigation analyzed against 18 items which include the BOD sampling. Consequently, for the optimum interpretation invasion water / inflow water of the this investigation area day average the lowest flow - water quality assessment veterinarian optimum interpretation hazard average per day - lowest flow - it averages a medulla evaluation law department one lowest flow evaluation technique and it selects, it presentation collectively from here it gets, position result with base flow analysis of invasion water / inflow water.

Potential Effect of Increased Water Temperature on Fish Habitats in Han River Watershed (수온 증가가 한강 수계의 어류 서식지에 미치는 영향)

  • Chung, Namil;Park, Baekyung;Kim, Kyunghyun
    • Journal of Korean Society on Water Environment
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    • v.27 no.3
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    • pp.314-321
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    • 2011
  • The potential effects of increased water temperature on fish assemblages and their habitats were studied in the streams of the Han River watershed when the water temperature was supposed to increase by $1^{\circ}C$, $2^{\circ}C$, and $3^{\circ}C$ in each sampling site. The percent changes in suitable habitats for each species and in species number within a site were determined, based on the estimated maximum thermal tolerances of 51 fish species whose habitats were classified into four reaches: upstream, up-/midstream, midstream, and mid-/downstream. The maximum thermal tolerance ranged between $25.0^{\circ}C$ and $31.0^{\circ}C$ and significantly increased as the habitat reaches move from upstream to mid-/downstream. With the increases in water temperature, the average suitable habitats for all 51 species were decreased by 31% ($+1^{\circ}C$), 46% ($+2^{\circ}C$), and 60% ($+3^{\circ}C$). The increased water temperature, however, did not induce significant differences in the changes in suitable habitats among four reaches within each level of temperature increase. The relative frequencies of the sampling sites classified into six levels according to the percent change in the number of species in each site were significantly different among three levels of water temperature increase, with relatively greater changes in the sites where 0~20% and 61~100% of species were affected.