• 제목/요약/키워드: Higher Concentration

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전남지역 일부 대학생 모발 중 수은 농도에 관한 연구 (A Study on Mercury Concentration in the Hair of University Students in Jeon-nam Area)

  • 송미라;조태진;전혜리;김종오;손부순
    • 한국환경보건학회지
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    • 제35권4호
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    • pp.287-294
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    • 2009
  • This study analysed the mercury concentration in the hair of 62 students (male : 21, female : 41) of D university in Najusi, Jeon-Nam area. Also, questionnaire, which developed by NIES, were completed by the students. According to the questionnaire, most of the students had a higher intake of meat than that of fish. Also, among the students, there were many smokes and many had dental treatment with amalgam. Based on the gender, female showed 1.024 ${\mu}g/g$ and male showed 0.882 ${\mu}g/g$ of the mercury concentration. This means that female students had higher level of mercury in their hair, but it was not a significant statistic difference. Comparing by the intake frequency of meat, processed food stuffs, protein foods, it shows the more they at the higher mercury concentration was observed. According to the intake frequency of fish, when the number of times they intake increased, the mercury concentration was higher. Under one time was 0.857 ${\mu}g/g$ and twice or more times were 1.152 ${\mu}g/g$, which showed a significant statistical difference (p<0.05). Depending on the Life style, the mercury concentration in the hair was high with workout, outdoor activities, and direct smoking. The mercury concentration in the hair showed no difference for whether they received amalgam treatment but the personal dietary habit and the Living condition affects strongly on the mercury concentration level.

버어리종 담배의 염소에 관한 연구 I. 버어리종 담배산지의 토양과 잎담배의 염소함량 실태 (STUDIES ON THE CHLORINE OF BURLEY TOBACCO PLANTS I. CHLORINE CONTENT OF THE SOIL AND CURED LEAF IN BURLEY TOBACCO GROWING AREA)

  • 김상범;배길관
    • 한국연초학회지
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    • 제8권1호
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    • pp.49-56
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    • 1986
  • To obtain the information of low chlorine leaf production, the chlorine content of the soil and cured leaf in Burley tobacco growing area was investigated. The results obtained are as follows. 1. The chlorine concentration in soil at transplanting time in Kwang-ju growing area was higher than in Jeon-ju(1983), and paddy field sell showed higher concentration of chlorine than upland field in Jeon-ju(1984). The chlorine concentration in soil was different between years, locations, and cultivated land (paddy field and upland field), but the concentration, on the whole, was under the levels that might effect the leaf quality. 2. The chlorine concentration In soil was highest around todays after transplanting, and after harvesting, the concentration decreased to half of transplanting time. 3. The distribution of chlorine through the parts of tobacco plant showed remarkable difference between years, locations, cultivated land and growing stages. 4. There was significant positive correlation between chlorine concentration in top soil and chlorine content of cured leaf. 5. Chlorine content of cured leaf in Kwang-ju area(1.79%) was higher than that of Jeon-ju area(O.79%), relatively. 6. It was considered that the accumulation of salt from the sea by sea. wind did not main factor of high leaf chlorine content in seaside district.

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돼지 수정란의 급속 동결 융해법에 관한 연구 - 돼지 동결 수정란에 대한 1단계 Straw법이 배의 생존성에 미치는 영향 (Studies on Rapid Freezing and Thawing of Porcine Embryos III. Factors affecting the survival rate of porcine embryos cryopreserved and diluted by one-step straw method)

  • 김상근;김무강;서길웅
    • 한국수정란이식학회지
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    • 제7권1호
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    • pp.13-19
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    • 1992
  • This study were carried out to investigate the effective concentration of cryoprotective agents and sucrose by one-step straw method, and to determine the optimum thawing temperature and equilibration time of frozen porcine embryos. The porcine embryos foflowing dehydration by cryoprotective agents and a various concentration of sucrose were directly plunged into liquid nitrogen and thawed in 3$0^{\circ}C$ water. Survival rate was defined by FDA test. The results are sunnnarized as follows : 1. The survival rates of porcine embryos after ultrarapid frozen4hawing in the freezing medium with a various concentration of glycerol, DMSO and propanediol added 0.25M sucrose were higher survival rate than those of sucrose concentration of 0.50M. 2. The survival rates of porcine embryos after ultrarapid ftozen4hawing in the freezing medium added 0.25M and 0.SOM sucrose were higher survival rate than those of sucrose concentration of 0.75M and 1.00M. 3. The temperature thawed at 2$0^{\circ}C$ and 3$0^{\circ}C$ resulted in a significantly higher embryos survival rate after 72 hrs in culture than did at 35$^{\circ}C$. 4. The equilibration time on the survival rate of porcine embryos was attained after short period of time(2.5~5 min.) in the freezing medium higher than long period of time(10~20 min.).

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폐금속광산지역의 하천퇴적물에서 중금속이 식물에 미치는 영향에 관한 연구 (Influence of Heavy Metal on Riparian Vegetation in Downstream Areas of Disused Metal Mines)

  • 안태웅;이정안;오종민
    • 환경영향평가
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    • 제18권4호
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    • pp.209-218
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    • 2009
  • The purpose of this study was to accumulation of the heavy metals by riparian vegetation throughout analysis of the heavy metal concentration in riparian vegetation, water, and sediment near mine drainage. According to analyzing concentration of the heavy metals in riparian vegetation, water, and sediment the heavy metal was indicated at the leaf significantly. Compared with the concentration of sediment soil, the maximum concentration of the As, Cd, CN, Pb, Zn was higher 2.6, 2.6, 25, non-detect, and 15 times in leaf. Also those concentration have 9.6, 16.6, 25, 1.6, and 25 times in root. As the results, the author can know the sediment has a very relative to vegetation in mine drainage. because, the increasing of concentration of heavy metal in sediment gives the more accumulative concentration of heavy metal in vegetation. Compared with the concentration of conta minated site and non-contaminated site. As, Cd, CN, Pb, Zn the maximum concentration in sediment soil was higher 5.7, 258.1, 10.9, 370.0, and 298.3 times respectively. In case of vegetation, the maximum concentration of the As, Cd, CN, Pb, Zn was higher 5.6, 62.3, 5.0, non-detect, and 30.6 times in leaf. Also those concentration have 8.5, 63.3, 2.6, 60.7, and 62.1 times in root. In this study, the author can surmise that there indicated a lot of adsorption with the heavy metal concentration in contaminated mine drainage.

서울에서의 VOCs의 히드록실 및 페록시 라디칼 농도에 대한 상대적 기여도 연구 (Relative Contribution of the Oxidation of VOCs to the Concentrations of Hydroxyl (OH) and Peroxy Radicals in the Air of Seoul Metropolitan Area)

  • 손장호
    • 한국대기환경학회지
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    • 제22권6호
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    • pp.779-790
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    • 2006
  • This study examines relative contributions of volatile organic compounds (VOCs) to the formation of hydroxyl (OH) and peroxy radicals such as $HO_2$ and $RO_2$ during the intensive sampling period (Jun. $1{\sim}30$, 2004) in the air of Seoul metropolitan area. As to the contribution of VOCs to $HO_x$ levels, the impact of individual VOC concentration change on $HO_2$ concentration change was more than an order of magnitude higher than that on OH concentration change during the study period. The contribution of change in isoprene concentration to $HO_2$ concentration change was 38 times higher than OH and that in the concentration of alkene compounds to $HO_2$ concentration change was 31 times higher than OH. Moreover, the concentration changes of isoprene and aromatic compounds (AROM) played significant roles in $HO_x$ concentration changes. On the other hands, aldehydes (ALD2) and alkanes (ALKA) showed anti-correlation (negative) in $HO_x$ concentration changes with low contribution ($-4{\times}10^{-3}$ pptv/ppbv (OH) and $-58{\times}10^{-3}$ ($HO_2$) for ALD2; $-1{\times}10^{-3}$ (OH) and $-15{\times}10^{-3}$ ($HO_2$) for ALKA). Unlike other VOCs, $C_2H_6$ and $C_3H_8$ showed positive or negative contribution to peroxy radicals, depending on ambient air conditions. The contribution of VOC concentration changes to changes in $CH_3O_2$ and $RO_2$ concentration showed similar pattern to $HO_x$ contribution.

잔디밭에서 기온과 이산화탄소 농도의 연직 변동 분석 (Vertical Variations Analysis of Air Temperature and CO2 Concentration in the Grassplots)

  • 소윤환;강동환;김일규;김병우;윤환진;김시현;손용석;신정현;안정우
    • 한국환경과학회지
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    • 제26권2호
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    • pp.147-157
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    • 2017
  • This study investigated the characteristics of variations in carbon dioxide concentration and air temperature with the vertical change of surface in a grassplot. Field observations were carried out at a grassplot in Gyeongnam Science High School, over four days in August and November, 2015. Continuous observation equipment (GMP343, VAISALA) was installed at the LP (0.1 m from the surface) and UP (1.1 m from the surface) points, and the carbon dioxide concentration and air temperature were measured simultaneously at 1-min intervals. To summarize the results of the observation, August had higher than average concentrations of carbon dioxide, while November showed average air temperatures. Moreover, the concentration of carbon dioxide was higher at the UP point, while the air temperature was higher at the LP point. The correlation coefficient of carbon dioxide concentration between the UP and LP points was 0.80 in August across all the four days, while it was higher in November at 0.58-0.95. The results of the regression analysis of carbon dioxide concentration with air temperature changes for both August and November showed a distinct change at the LP point (R2=0.36-0.76), as compared to the UP point (R2=0.1-0.57). Between the UP and LP points, the carbon dioxide concentration and air temperature regression analysis results indicated that an active exchange was taking place between the two points.

소형 직화식 커피 로스터 이용 시 발생하는 미세먼지 특성 연구 (Characteristics of Particulate Matter Generated during the Operation of a Small Directly Fired Coffee Roaster)

  • 유다은;김승원
    • 한국산업보건학회지
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    • 제30권2호
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    • pp.236-248
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    • 2020
  • Objectives: The purpose of this study was to evaluate the concentrations of particulate matter generated during coffee roasting and to study various factors affecting the concentrations. Methods: Differences in concentration levels were investigated based on various factors to understand the emission rates of particulate matter over time and to compare the mass and number concentrations according to their size. Sampling was performed in closed laboratories without the operation of air conditioning or ventilation. Optical Particle Sizer(OPS) was used as a measuring device. An OPS measures using a light-scattering method. Sampling was performed for sixty minutes at one-minute intervals. The background concentration was measured for about 30 minutes before starting of coffee roasting. The concentrations of particulate matter generated during coffee roasting were monitored until roasted coffee beans were removed from the roaster and cooled down. Several factors affecting the concentrations of particulate matter were investigated, which includes the origins of green beans, the roasting level, and the input amount of green beans. Results: The results of this study may be summarized as follows: 1) There was no difference in particulate matter concentration levels by the origin of the green beans, but a statistically significant difference in concentration levels by roasting level and the input amount of green beans; The higher the roasting level, the higher was the particulate matter concentration. The more green beans we put in the roaster, the higher were the concentrations; 2) The PM10 mass concentrations increased over time. The average concentration after roasting was higher than the average concentration during roasting; 3) In the distribution of mass and number concentration by particle diameter, the majority of particles was below 2.5 ㎛. Conclusions: Persons who work in roastery cafes can be exposed to high concentrations of particulate matter. Therefore, personal exposure and risk assessment should be conducted for roastery cafe workers.

Medium compositions reveal potential organogenesis in the diploid and tetrploid Codonopsis lanceolata

  • Kwon, Soo Jeong;Hwang, Ha Nule;Moon, Young Ja;Cho, Gab Yeon;Boo, Hee Ock;Lee, Moon Soon;Woo, Sun Hee;Kim, Hag Hyun
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.169-169
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    • 2017
  • Medium composition plays a key role on influencing organogenesis in plant tissue culture. This study was carried out to examine the effects of medium composition on organogenesis in diploid and tetraploid Codonopsis lanceolata and obtain in-vitro mass propagation of superior species of C. lanceolata. Diploid C. lanceolata was found to be declined regarding MS medium composition for each concentration. However, shoot and adventitious root formation were suppressed with higher mineral salt concentration, and active growth of shoot and adventitious root was exhibited as 4.9 cm and 3.2 cm respectively in 1/2 MS medium. While in tetraploid C. lanceolata, it showed 2.9 cm and 3.2 cm respectively in 1/4 MS medium. In the case of sucrose concentration, no consistent decrease was observed for growth of shoot and the adventitious root of diploid both at high and low concentration. The growth of shoot (at 3% concentration) and adventitious root (at 7% concentration) was 2.3 cm and 2.0 cm respectively. Although there was no difference in shoot formation of tetraploid C. lanceolata in all concentrations with the range of 1.7~1.8, there was a slight decrease in shoot growth at high concentration. Results revealed that the adventitious root formation was suppressed at high concentration. The concentration of agar exhibited no significant difference in shoot formation of diploid C. lanceolata at all concentrations. The maximum result of adventitious growth (4.1 cm) was observed at 0.8% concentration. Slight inhibition of shoot formation and root formation of tetraploid C. lanceolata was observed at higher concentration. Shoot formation of diploid C. lanceolata also exhibited inhibition at higher concentration. Shoot formation of diploid C. lanceolata was increased at lower pH and shoot growth was the highest (2.3 cm) at pH 3.8. Adventitious root formation was higher at lower pH. However, both the adventitious root formation and growth exhibited comparatively higher result at pH 5.8. Taken together, the levels of pH had an effect on shoot and root formation in diploid and tetraploid of C. lanceolata

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폐의 편평세포 암종 조직내 SCC항원 및 EGFr치에 대한 연구 (A Study of SCC Antigen and EGFr in Tissues of Squamous Cell Carcinoma of Lung)

  • 이창민;조성래
    • Journal of Chest Surgery
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    • 제31권4호
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    • pp.362-368
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    • 1998
  • 편평세포폐암 환자 혈청내 SCC항원(squamous cell carcinoma antigen)의 암표지자로서의 유용성을 검정하고 암종이 성장함으로써 정상조직으로 침범하는 기전을 규명하기 위하여 폐암수술후 절제해 낸 폐암조직의 중심부와 말초부 그리고 암세포가 없는 정상 폐조직을 채취하여 SCC항원 농도와 DNA합성을 통해 세포성장과 분화에 관련이 있는 것으로 알려진 EGFr(epidermal growth factor receptor)의 농도를 측정하였다. 편평세포폐암종 조직내 SCC항원의 농도는 69+25 ng/ml로 정상 폐조직 34+7 ng/ml, 폐선암 35+25 ng/ml보다 높았으며(p<0.05), EGFr의 농도는 폐암조직, 즉 편평세포암 47+6 pmol/min, 선암 69+20 pmol/min으로 정상 폐조직 34+5 pmol/min, 39+8 pmol/min보다 각각 높게는 나타났으나 유의성은 없었다. 암종의 크기에 따른 부위별 SCC항원의 농도는 암종이 직경이 3cm이하인 경우는 암종의 중심부(100+82 ng/ml)가 말초부(55+24 ng/ml)보다 높게 나타났으나(p>0.05), 5cm이상인 경우는 암종의 말초부(324+92 ng/ml)가 중심부(34+18 ng/ml)보다 현저히 높았다.(p<0.05) 그러나 부위별 EGFr의 농도는 암종의 크기에 따라 차이가 없었다. 암병기에 따른 부위별 SCC항원의 농도는 암중심부에서는 1, 2병기에서 3, 4병기로 암병기가 높아짐에 따라 감소하는 경향을 보였으나 통계적 유의성은 없었고(p>0.05), 암말초부에서는 1, 2병기 68+37 ng/ml, 87+35 ng/ml에서 3,4병기414+87 ng/ml, 473+226 ng/ml로 병기가 높아짐에 따라 현저하게 증가하였다.(p<0.05) 그러나 EGFr은 암중심부에서 1병기에서 2, 3, 4병기로 병기가 높아짐에 따라 증가하는 경향을 보였으나 통계적 유의성이 없었고(p<0.05), 암말초부에서는 병기에 따른 농도의 특이한 변화를 관찰할 수 없었다. 이상의 결과로 편평세포폐암종 조직내 SCC항원의 농도는 정상 폐조직이나 폐선암조직에서 보다 높게 나타나 혈청내 SCC항원의 농도가 편평세포폐암의 진단 및 치료효과를 예측하는데 유용한 암표지자로 생각되나, 암종내 부위별 SCC항원의 농도와 EGFr의 농도가 일치하지 않음으로써 암종이 성장함으로써 주위조직으로의 침범과 SCC항원의 농도와의 관계에 대해서는 보다 더 많은 연구가 필요할 것으로 사료된다.

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미세먼지 농도의 공간적 현황 및 잠재영향인자를 고려한 환경계획적 대응 방향 (Environmental Planning Contermeasures Considering Spatial Distribution and Potential Factors of Particulate Matters Concentration)

  • 성선용
    • 한국환경복원기술학회지
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    • 제23권1호
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    • pp.89-96
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    • 2020
  • Adverse impact of Particulate Matters(PM10, PM2.5; PMs) significantly affects daily lives. Major countermeasures for reducing concentration of PMs were focused on emission source without considering spatial difference of PMs concentration. Thus, this study analyzed spatial·temporal distribution of PMs with observation data as well as potential contributing factors on PMs concentration. The annual average concentration of PMs have been decreased while the particulate matter warnings and alerts were significantly increased in 2018. The average concentration of PMs in spring and winter was higher than the other seasons. Also, the spatial distribution of PMs were also showed seasonality while concentration of PMs were higher in Seoul-metropolitan areas in all seasons. Climate variables, emission source, spatial structure and potential PM sinks were selected major factors which could affects on ambient concentrations of PMs. This paper suggest that countermeasures for mitigating PM concentration should consider characteristics of area. Climatic variables(temperature, pressure, wind speed etc.) affects concentrations of PMs. The effects of spatial structure of cities(terrain, ventilation corridor) and biological sinks(green infrastructure, urban forests) on concentration of PMs should be analyzed in further studies. Also, seasonality of PMs concentration should be considered for establishing effective countermeasures to reduce ambient PMs concentration.