• 한국해양학회지:바다
• /
• 제21권4호
• /
• pp.125-133
• /
• 2016

본 연구는 통영연안의 오염 현황을 파악하기 위하여 표층퇴적물의 유기물 분포 특성, 미량금속의 공간적인 분포 특성과 오염도 및 생태계 위해성평가를 하였다. 총질소(Total nitrogen, TN), 총유기탄소(Total organic carbon, TOC)와 산 휘발성 황화물(Acid volatile sulfide, AVS)은 협수로에 위치한 정점 35-38에서 높은 농도를 나타내었다. Cd, Cr, Ni, Co, Hg, Zn의 공간적 분포양상은 유사하였으며, 이와 달리 Cu는 협수로에서 높은 농도를 나타내었다. 미량금속 원소의 오염도를 농축계수(Enrichment Factor, EF)로 평가한 결과, Cd이 모든 정점에서 오염되지 않은 상태(No enrichment), Pb, Cr, Ni, Co, Zn, Hg이 약간 오염상태(Minor enrichment), Cu가 약간~중간 오염상태(minor-moderate enrichment)의 오염도를 나타냈다. 미량금속에 의한 생태위해성 수준은 오비도와 미륵도 사이의 협수로 정점에서 국지적으로 생태계에 잠재적 위해성이 있는 것으로 나타났다.

• 자원환경지질
• /
• 제42권3호
• /
• pp.195-206
• /
• 2009

함양-산청지역 하상퇴적물의 자연배경치와 부화특성을 알아보고, 지구화학적 재해에 대해 예견하였다. 오염의 우려가 없고, 집수분지를 대표할 수 있는 하상퇴적물 시료를 채취하였다. XRF, ICP-AES와 NAA 분석을 이용하여 주성분원소와 유해원소 함량을 얻었다. 산분해법은 1차로 $HClO_4$와 HF를 혼합하여 $200^{\circ}C$에서 분해시킨 후, 2차로 $HClO_4$, HF 및 HCl를 혼합한 후 $200^{\circ}C$에서 분해시켜 이를 1% $HNO_3$용액으로 만들었다. 상관분석에서 하상퇴적물의 $SiO_2$ 함량이 증가할수록 Cu와 Co의 함량이 감소하는 특징을 보임을 알 수 있었다. 함양-산청내 환경유해원소 대부분 부화지수 2 이하로 부화되어 있었으며, 함양지역 하상퇴적물은 Pb>Th>Cr>V>Co>Cu순으로, 산청지역 하상퇴적물은 Pb>Th>Cr>Co>V>Cu순으로 부화되어 있었다. Pb, Cr, Co 및 V의 부화지수는 함양지역과 산청지역에서 거의 비슷한 부화특성을 보였으나, Th의 부화지수는 함양지역 지역에서, Cu의 부화지수는 산청지역에서 높은 부화특성을 보였다. Pb의 부화지수는 각각 2.24(함양), 2.57(산청) 이상으로 부화되어 있었지만, 토양 및 환경오염 허용 한계치(tolerable level)를 이용하여 살펴본 결과에서는 오염에 특별히 노출되지 않은 것으로 판단된다.

• 한국미생물·생명공학회지
• /
• 제24권6호
• /
• pp.647-651
• /
• 1996

The development of an enrichment method for the rapid and effective identification of Salmonella spp. in sewage or food was studied. As a growth factor for Salmonella, 10 mM cyclic adenosine monophosphate (cAMP) in trypticase soy broth with 0.6% yeast extract (TSBYE) increased cell number five-folds and 0.6% yeast extract in selenite broth increased cell number ten-folds of control. Bile salts in selenite broth was tested for the selection of S. enteritidis in a mixture with Staphylococcus aureus, Pseudomonas aeruginosa, Lactobacillus plantarum and Escherichia coli. The latter four strains were effectively inhibited at 0.1% bile salt. A two-step culture method was used to enrich Salmonella spp.; a primary-enrichment and secondary- enrichment culture. At a primary-enrichment step, selenite broth with 0.6% yeast extract and 10 mM cAMP was used, and at a secondary-enrichment step, 0.1% bile salt was additionally used. Culture times of a primary- enrichment and a secondary-enrichment step were 8 hr and 6 hr, respectively. In this procedure, cell number increased from 10$^{0.3}$ to 10$^{8.5}$ with inhibition of other strains within 14 hr. In the case of an initial cell concentrarion as low as 10$^{-2}$ cfu/ml, a cell number increased to 10$^{7}$ cfu/ml by using a 10 hr primary-enrichment and 6 hr secondary-enrichment procedure.

• 한국지반환경공학회 논문집
• /
• 제19권11호
• /
• pp.15-22
• /
• 2018

본 연구는 광안대교 인근의 해저퇴적토에 포함된 중금속을 분석하여 퇴적토의 오염도를 평가하고자 하였다. 오염도 평가를 위해 Enrichment Factor(EF), Geoaccumulation index, Potential ecological risk factor(PERF), mean PEL quotient와 같은 평가방법을 사용하였다. 각 평가방법에 따라 대상 지역의 중금속 오염 정도를 확인하였고 이를 종합적으로 고려하여 어떤 지역에서 어떤 중금속이 문제가 되는지를 확인하였다. Cr, Cu, Ni, Pb, Zn의 경우 전 지역에서 비오염 혹은 영향없음으로 판별되었으나(EF<1) Cd의 경우에는 모든 지역에서 외부영향으로 인한 농도증가 양상을 보여주었다(1$I_{geo}$에 의한 평가에서는 Cd의 경우 G4에서 다소 오염으로 분류되었으나 다른 지역에서는 모두 비오염으로 평가되었다. 각 평가방법에 의한 결과를 요약하면 Cd의 경우 전 지역에서 높게 검출되었고 지역별로는 G4와 G5 지역에서 Cd를 비롯하여 Pb와 Zn의 농도가 다른 지역보다 다소 높은 것으로 확인되었다.

• The Journal of Korean Physical Therapy
• /
• 제19권4호
• /
• pp.33-41
• /
• 2007

Purpose: To investigate environmental enrichment and nerve stimulation follows in application times with the change of BDNF & Trk-B receptor in the motor cortex and spinal cord. Methods: Experimental groups were divided into the five groups. Group I: normal control group, Group II: experiment control group, Group III: sciatic never electrical stimulation after MCAO, Group IV: application of only environmental enrichment after MCAO, Group V: never electrical stimulation with environmental enrichment after MCAO. Histologic observation and coronal sections were processed individually in goat polyclonal antibody phosphorylated BDNF and rabbit polyclonal antibody Trk-B receptor. Results: In immunohistochemistric response of BDNF and Trk-B, group II were showed that lower response effect at postischemic 1 days, 3 days, and 7 days. Group V were showed that increase response effect at postischemic 3 days, 7 days and 14 days. Specially showed that the most response effect at postischemic 14 days. In neurobehavioral assessment, group V were significantly difference from other groups on between-subject effects. Conclusion: The above results suggest that combined environmental enrichment with peripheral nerve electrical stimulation in focal ischemic brain injury were more improved that the change of BDNF & Trk-B receptor expression than non treatment.

• Bulletin of the Korean Chemical Society
• /
• 제19권7호
• /
• pp.766-770
• /
• 1998

On-line preconcentration by direct precipitation with hydroxide has been developed and applied for the analysis of Cd in Inductively Coupled Plasma Atomic Emission Spectrometry. Cadmium is continuously precipitated with hydroxide and dissolved by nitric acid in on-line mode. Currently, the enrichment factor is more than 90 times for 20.0 mL of sample and could be further increased very easily. For a large sample throughput, 1.0 mL of sample loop is used and the enrichment factor is 4.5 with the sampling speed of 15/hr. The method has been applied to the analysis of NIST reference sample and has yielded good results with the certified value.

• 영재교육연구
• /
• 제8권1호
• /
• pp.7-38
• /
• 1998

In order to explore the science enrichment learning program for the science gifted in general elemetary and secondary schoo1,the identification of the science gifted, gifted education methods and science education cumculums were investigated through literature survey. Admitting the Renzulli's enrichment triad model and three dmensional scienctific factors as context, process and content, the snow ball program was explored. Identification methods and science education cumculum of enrichment learning for the science gifted were presented. In the snow ball program, it was presented that each factor of three dimensional scienctific factors was focused in the different ways due to the levels or the ages of students. The examples of the snow ball program and science education cumculum of enrichment learning for the science gifted were illustrated.

• 한국병원경영학회지
• /
• 제26권1호
• /
• pp.26-41
• /
• 2021

Purpose: This study is to identify the relationship among married nurses' social support, work-family conflict and work-family enrichment and to examine the influence of social support on work-family conflict and work-family enrichment. Methods: Data were collected from married nurses working at three hospitals with more than 100 beds in J Province and analyzed by descriptive statistics, t-test, ANOVA, Mann-Whitney U test, Kruskal-Wallis H test, Pearson's correlation analysis and hierarchical regression analysis using SPSS 21 program. Findings: In the correlation analysis only social support and work-family enrichment showed positive correlation. As a result of hierarchical multiple regression analysis, social support still acted as a significant influence factor on work-family conflict and work-family enrichment even in the state of considering the effect of control variables. Conclusion: In order to lower work-family conflict and to enhance work-family enrichment of married nurses, it is necessary to introduce and implement welfare policies for work-family reconciliation at the workplace level and at home level it is necessary to provide concrete measures so that married nurses can find the value of life as workers while house working and nurturing.

• 한국환경보건학회지
• /
• 제29권1호
• /
• pp.67-73
• /
• 2003

This study was carried out to characterize the behavior and sources of particulate trace metal in Daegu city. TSP (Total Suspended Particulate matter) was collected by filters on High Volume Air Sampler from the four areal (reference, residential, commercial, industrial area). The moult were analyzed by AAS after preliminary treatment. The average centration trend of trace metals contained in TSP was shown as follows : Fe > Cu > Pb > Mn > Ni > Cr > Cd. The trace metals showed the highest concentration in the industrial area. This study showed the seasonal variation of trace metals. Fe and Mn showed high concentration in spring, whereas Cr, Ni, Cd and Pb showed high concentration in winter. Also this study showed the regional variation of trace metals. The order of the average concentration of trace metals was : industrial > commercial > residential > reference area. Using Mn as a reference element, the enrichment factor analysis were used for identifying the trace element contributors. The enrichment factors of Cr, Fe < 10 were considered to have a significant dust and soil source and termed nonenriched. Pb, Cd, Cu >>10 were enriched and had a significant fraction which was contributed by anthropogenic sources.

• 한국환경과학회지
• /
• 제21권11호
• /
• pp.1339-1348
• /
• 2012

The versatile aerosol concentration enrichment system (VACES) have proven useful for providing elevated levels of atmospheric aerosol to human and animal exposures. In this study, we describe a VACES and tests conducted to both optimize the enhancement factor (EF) and characterize how it depends on experiment conditions. Particle number concentrations were measured from upstream and downstream of the system by scanning mobility particle sizer (SMPS) with a long differential mobility analyzer (DMA) in combination with a condensation particle counter (CPC). SMPS was used for to determine VACES particle EF. Particle EF tends to increase for higher the saturator temperature ($T_{Sat}$) and lower the condenser temperature ($T_{Con}$). $T_{Con}$ higher than $0^{\circ}C$ and $T_{Sat}$ lower than $50^{\circ}C$ was the best to obtain the most increase in particle concentration. Correlation analysis of EF with factor variables of $T_{Sat}$ and $T_{Con}$ resulted in correlation 0.662 and 0.416, respectively. With all five predictor variables included in a multiple regression model, the EF had a liner correlation with $R^2=0.643$.