• 생태와환경
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• 제43권4호
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• pp.492-502
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• 2010

The study objects were to analyze long-term and seasonal variations of nutrients (N, P), suspended solids, N:P ratios, algal chlorophyll, and trophic state along with general water quality parameters in four sampling sites including two intake tower sites supplying drinking water in Daechung Reservoir. For the analysis, we used water quality long-term data sampled during 1998~2007 by the Ministry of Environment, Korea. Interannual and seasonal trends in inflow and discharge near the intake tower facilities over the ten years were directly influenced by rainfall pattern. The distinct difference between wet year (2003) and dry year (2001) produced marked differences in water temperature, pH, dissolved oxygen, organic matter contents, nutrients, and these variables influenced algal biomass and trophic state. Values of TP varied depending on the year and locations sampled, but monthly mean TP always peaked during July~August when river inflow and precipitation were maxima. In contrast, TN varied little compared to TP, indicating lower influence by seasonal flow compared to phosphorus. The number of E. coli were highest in Site 2 (Chudong intake tower) and varied largely, whereas at other sites, the numbers were low and low variations. Contents of chlorophyll-${\alpha}$ (CHL), as an estimation of primary productivity, varied largely depending on the year and season. The maximum of CHL occurred at Muneu intake tower (S4) during 2006 when the precipitation and inflow were lowest. In contrast, another CHL peak was observed in Site 2 (Chudong intake tower) in 2006 when one of the largest typoons (Ewinia) occurred and river runoff were maximum. So the CHL maxima were associated with both wet year (high flow, high nutrient supply) and dry year (low flow, nutrient supply by littoral zone). Such conditions influenced trophic states, based on Trophic State Index of nutrients and CHL. Based on all analyses, we can provide some clues for management and protection strategies of two intake tower sites.

• 공업화학
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• 제31권5호
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• pp.481-486
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• 2020

삼척항 내 표층 퇴적물에 대한 지화학적 특성을 파악하기 위하여 입도, 유기물 및 중금속 분포 특성을 조사하였다. 삼척항 퇴적물은 sand, silt, clay가 혼재된 특성을 보였으며, 내항에는 세립질이 우세하였고, 외항에는 조립질이 우세한 것으로 나타났다. 표층 퇴적물의 유기물(COD, TOC, IL) 오염정도는 내항이 외항보다 더 심한 것으로 나타났으며, 총질소 및 총인 농도도 내항이 더 높은 것으로 나타나고 있다. 또한 중금속 농도도 외항보다 내항에서 더 높았다(As 제외). 내항 표층 퇴적물의 높은 유기물 농도 및 C/N비로 보아 육상 유래 유기물의 오염 기여가 큰 것으로 판단된다. 표층 퇴적물의 입도, 이화학적 성분, 중금속 간의 상관성 분석에서 silt-clay는 중금속과 높은 상관성을 보였고, 유기물 지표와 중금속간의 상관성도 대체적으로 높게 나타났다. 중금속 연속추출결과에 따르면 Ni, Zn, Cu, Pb, Cd 및 As는 이온교환, 탄산염, 산화물 형태를 합한 평균 존재비가 각각 14.8, 49.8, 39.1, 32.2, 51.8 및 26.6%이었다.

• 한국양식학회지
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• 제16권3호
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• pp.171-178
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• 2003

Inorganic nutrients such as nitrogen and phosphate compounds accumulate in recirculating aquaculture systems. These nutrients must be removed from the system before they affect pH and fish health. For this purpose, aquatic plants are a simple and inexpensive method of removal. There are four commonly used aquatic plants: Eichhornia crassipes (water hyacinth), Pistia stratiotes (water lettuce), Hygrophila angustifolia, and Hydrocotyle leucocephala in freshwater recirculating aquaculture systems in Korea, but their efficiencies are not known. Therefore, removal efficiencies of inorganic nutrients from a freshwater recirculating aquaculture water with four commonly used aquatic plants were tested. Removing efficiencies of TAN, N $O_2$$^{[-10]}$ -N, and N $O_3$$^{[-10]}$ -N of the plants in 210 L aquaria for 48-hour period were tested. The removing efficiencies of TAN, N $O_3$$^{[-10]}$ -N, and P $O_4$$^{3-}$-P of the two most effective plants, water hyacinth and water lettuce, were also tested in 690 L (surface area of 1.55 $m^2$) tanks under 2 different initial stocking densities, 4 kg and 6 kg, for 22 days. Proximate analysis major nutrients and N and P contents of the all plants were analyzed for calculating net removal weight of N and P by the plants. Water lettuce was the most effective for removing TAN, N $O_2$$^{[-10]}$ -N, and N $O_3$$^{[-10]}$ -N from the water for 48-hour period tested followed by water hyacinth and Hygrophila angustifolia. Water lettuce reduced TAN, N $O_2$$^{[-10]}$ -N, and N $O_3$$^{[-10]}$ -N concentration from 2.3 mg/L, 0.197 mg/L, and 21.4 mg/L to 0.4 mg/L, 0.024 mg/L and 17.4 mg/L, respectively while water hyacinth reduced them down to 0.6 mg/L, 0.029 mg/L and 17.9 mg/L, respectively. The concentrations of TAN, N $O_2$$^{[-10]}$ -N, and N $O_3$$^{[-10]}$ -N in Hydrocotyle leucocephala group were rather increased up to 3.7 mg/L, 5.7 mg/L and 48.2 mg/L, respectively. This is because the creeping stem of Hydrocotyle leucocephala had to be cut to meet stocking weight resulting in decaying of the stem in the aquaria during experiment. The net growth in weight of water hycinth and water lettuce of 4 kg each in the 1.55 $m^2$ tanks for 22 days were 9.768 kg and 10.803 kg respectively, and those at initial weight of 6 kg each were 8.393 kg and 9.433 kg, respectively. The reason of lower net growth in the later group was restricted growth space. Nitrogen and phosphorus contents in water hyacinth were 2.89% and 0.27%, and those in water lettuce were 3.87% and 0.36%, respectively. Average quantities of removed N and P from 1.55 $m^2$ tanks by water hyacinth for 22 days were 18.9 g and 1.75 g, while those by water lettuce were 36.8 g and 3.5 g, respectively. Therefore water lettuce showed much higher efficiencies for removing both N and P from recirculating aquaculture water than water hyacinth.

• 대한영양사협회학술지
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• 제12권4호
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• pp.378-389
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• 2006

The purpose of this study was to investigate the status of magnesium, iron, copper and zinc nutrition in 28 normal and 28 obese male elementary school students who have over 30% obesity index. The anthropometric measurements, dietary intakes and serum levels of magnesium, iron, copper and zinc were determined by 24-hr recall method and blood analysis, respectively. The mean age, height, weight, and obesity index were 10.9years, 147.4cm, 61.1kg, and 50.5% in obese group and 10.8years, 145.4cm, 40.2kg, and 3.3% in normal group. There was no significant difference in average daily food intake between obese and normal group, but meats(p＜0.05) intake of obese group was significantly lower than that of normal group. The intakes of energy, magnesium, iron, copper were not significantly difference between obese and normal group, but heme iron(p＜0.05) intake of obese group was significantly lower than that of normal group. Zinc(p＜0.05) intake of obese group was significantly higher than that of normal group. Serum magnesium(p＜0.001) level of obese group was significantly higher than that of normal group, but there were no significant differences in serum iron, copper, zinc levels between obese and normal group. There was a significantly positive correlation between serum magnesium and weight(p＜0.05), and obesity index(p＜0.05). There was a significantly positive correlation between serum magnesium and energy intake(p＜0.05), protein intake(p＜0.05), animal protein intake(p＜0.05), phosphorus intake(p＜0.05) and animal iron intake(p＜0.05). There was a significantly positive correlation between serum magnesium and seaweeds intake(p＜0.05), milks intake(p＜0.001). Also, there was significantly positive correlation between serum copper and oils and fat intake(p＜0.05). These results suggest that there should be careful considerations for micronutrients nutrition status among male obese elementary school students.

• 대한환경공학회지
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• 제34권6호
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• pp.421-429
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• 2012

본 연구는 화포천 수질 현황을 제시하여 특성을 분석하고 향후 관련연구에 활용할 목적으로 수행되었다. 상류에서는 step-pool 형태의 14개의 보로 인해 하천수가 저류되었고 주거단지 및 농경지를 지나면서 생활하수와 관개용수 등의 오염물 유입이 있었다. 이러한 이유로 정체구역의 하상에서 사상성 남조류인 Oscillatoria 군락이 번무하였으며 하천의 중 하류에서는 고모천(T3), 용덕천(T8)과 같이 N, P가 높은 고농도 지류가 유입되는 등 본류 수질을 악화시켰다. 화포천은 하류로 갈수록 DO가 감소하고 SS가 증가한 것이 특징적이었다. 상관관계 분석결과 긴 체류시간과 SS, COD, $NH_4{^+}$가 화포천에서 중요한 수질인자임을 나타내었다. 또한, 습지에서 하상 유기물 농도가 높고 부착조류가 풍부한 점도 본류 수질에 영향을 줄 것으로 판단되었다. 화포천 수질은 공간적으로 보가 있는 구간에서 농도가 상승하였고 하류의 습지에서는 일정하거나 소폭 감소하였다. 계절적으로는 겨울에 영양염 농도가 높았으나 여름에는 유기물 농도가 높았다. 식물플랑크톤은 6월에 보와 습지 등 정체구간에서 높게 나타난 점을 제외하면 전 구간에서 $40{\mu}g\;chl-{\alpha}/L$ 이하로 나타났다.

• 한국식품과학회지
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• 제36권5호
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• pp.800-803
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• 2004

도토리 가루를 이용하여 기능성 식품개발을 목적으로 도토리 가루의 화학성분, 항산화 활성을 조사하였다. 일반성분은 탄수화물이 87.29%, 수분 10.57%, 조지방 1.18%, 조단백 0.84%, 회분 0.12% 순으로 나타났다. 도토리 가루에 가장 많은 무기성분으로는 K이 40.68mg/100g으로 나타났으며, 그 외 P(8.95mg/100g), Ca(8.64mg/100g), Mg(4.67mg/100g), Na(3.94mg/100g), Fe(1.41mg/100g) 순으로 나타났다. 구성당은 총 7종이 분리 동정되었으며, 그 중 glucose가 대부분으로 나타났고 rhamnose, galactose, arabinose, mannose, fucose, xylose 순으로 함유되어 있었다. 주요 지방산 조성은 oleic acid(C18:1)가 31.87%로 가장 높았고, linoleic acid(C18:2)는 18.72%, linolenic acid(C18:3)는 16.67% 그리고 palmitic acid(C16:0)가 11.32% 순으로 나타났다. 항산화 효과는 물 추출물에서 $IC_{50}$가 $19.0{\mu}g/mL$로 가장 높게 측정되었고 75% 에탄올 추출물$(IC_{50}:\;21.4{\mu}g/mL)$ 및 메탄올 추출물$(IC_{50}:\;45.2{\mu}g/mL)$순으로 항산화 효과가 측정되었다.

• 한국산림과학회지
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• 제102권2호
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• pp.255-263
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• 2013

이 연구는 지리산 지역 둘레길의 토양물리성 및 화학성 변화를 분석하여 둘레길 노면토양의 피해 저감 및 관리를 위한 기초적인 자료를 마련하기 위하여 수행하였다. 지리산 둘레길과 주변 산림지역의 평균적인 토양의 특성을 분석한 결과 둘레길 노면의 토양은 사양토이었으며, 산림지역의 토성은 양토로 분석되었다. 토양용적밀도의 값은 산림지역 1.00 g/$cm^3$과 둘레길 노면 토양 1.15 g/$cm^3$로 산림지역과 둘레길 노면 토양 사이의 토양용적밀도는 유의적인 차이가 있는 것으로(P<0.05) 나타났다. 산림지역과 둘레길 노면토양의 평균토양공극률을 비교한 결과 산림지역의 평균토양공극률은 62.4%로 둘레길 노면 토양의 평균토양공극률 56.6%에 비해 산림지역의 평균토양공극률이 5.8% 높은 값을 나타내었다. 토양 내 수분함유율의 경우 산림지역에서 11.3%, 둘레길 노면 토양에서 13.3%로 둘레길 노면토양의 평균토양수분함유율이 약 2.0% 높게 나타났으며, 두 지역 간 유의적 차이는 없는 것으로(P>0.05) 나타났다. 인위적 답압에 의한 영향이 높은 토양깊이 5 cm에서의 토양경도는 조사구간의 10 cm에서보다 높게 나타나 이용자의 답압에 의한 둘레길길 영향은 현재까지 토양 5 cm 정도까지 미치는 것으로 분석되었다. 또한 토양깊이 30cm 이상에서 토양경도는 산림지역과 둘레길의 차이가 없는 것으로 나타났다. 둘레길 노면토양의 화학성을 분석한 결과, 유기물, 전질소, 유효인산, 치환성양이온($K^+$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$) 모두 적정함량에 부족한 값을 나타내었는데, 이는 둘레길의 이용객의 증가에 따른 토양침식 등으로 인한 것으로 사료되며, 이를 억지하기 위해서는 이용자의 과도한 집중화 및 분산을 유도할 수 있는 방법을 강구할 필요가 있다고 사료된다.

• Journal of Radiation Protection and Research
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• 제41권4호
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• pp.359-367
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• 2016

Background: As new legislation has come into force implementing radiation safety management for the use of naturally occurring radioactive materials (NORM), it is necessary to establish a rapid and accurate measurement technique. Measurement of $^{238}U$ and $^{232}Th$ using conventional methods encounter the most significant difficulties for pretreatment (e.g., purification, speciation, and dilution/enrichment) or require time-consuming processes. Therefore, in this study, the applicability of ED-XRF as a non-destructive and rapid screening method was validated for raw materials and by-product samples. Materials and Methods: A series of experiments was conducted to test the applicability for rapid screening of XRF measurement to determine activity of $^{238}U$ and $^{232}Th$ based on certified reference materials (e.g., soil, rock, phosphorus rock, bauxite, zircon, and coal ash) and NORM samples commercially used in Korea. Statistical methods were used to compare the analytical results of ED-XRF to those of certified values of certified reference materials (CRM) and inductively coupled plasma mass spectrometry (ICP-MS). Results and Discussion: Results of the XRF measurement for $^{238}U$ and $^{232}Th$ showed under 20% relative error and standard deviation. The results of the U-test were statistically significant except for the case of U in coal fly ash samples. In addition, analytical results of $^{238}U$ and $^{232}Th$ in the raw material and by-product samples using XRF and the analytical results of those using ICP-MS ($R^2{\geq}0.95$) were consistent with each other. Thus, the analytical results rapidly derived using ED-XRF were fairly reliable. Conclusion: Based on the validation results, it can be concluded that the ED-XRF analysis may be applied to rapid screening of radioactivities ($^{238}U$ and $^{232}Th$) in NORM samples.

• 동아시아식생활학회지
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• 제9권3호
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• pp.302-314
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• 1999

This study was conducted to evaluate nutrient intake, indices of anemia, serum lipids, and their correlations in 40 Korean female college students aged 21 to 25 years. Fasting blood samples were collected in October. 1997 Nutrient intake was investigated by 24-hour recall method for three days. Anthropometric measurements, blood pressure, iron status and serum lipids of the subjects were determined. The mean values for age. height, weight, BMI and blood pressure of the subjects were 22.1 years, 160.6cm, 54.4kg and 109.1/66.9mmHg, respectively. According to the body composition analysis, total body water, % body fat, lean body mass and WHR were 26.7L. 29.5%, 36.5kg and 0.8, respectively. Average daily intake of energy was 1,858.4kcal. Protein, phosphorus, vitamin B$_1$, vitamin B$_2$, niacin and vitamin C intakes were higher than the Korean recommended dietary allowence(RDA), whereas calcium, iron, vitamin A intakes were tower than that. Hemoglobin(Hb), hematocrit(Hct), serum iron(SI) and total iron binding capacity(TIBC) were measured and transferrin saturation (TS%) was calculated from serum. The mean values for Hb, Hct, SI, TIBC and TS were 13.6$\mu\textrm{g}$/㎗, 41.6%,97.8$\mu\textrm{g}$/㎗, 319.6$\mu\textrm{g}$/㎗ and 31.9%, respectively. The Prevalence rates of iron deficiency assessed by Hb and Hct were found to be 10% and 2.5%, respectively. However, when assessed with TIBC, the prevalence rate of iron deficiency was increased to 32.5%. The mean values for serum triglyceride(TG), total cholesterol(TC), HDL-Chol, LDL-Chol concentrations and atherogenic index(AI) were 154.7mg/㎗, 80.0mg/㎗, 47.4mg/㎗, 91.3mg/㎗ and 2.6, respectively. Correlations among indices of anemia. there were positive correlations between Hb and Hct, between SI and TS : negative correlations between TIBC and TS or SI. Correlations among serum lipids, there were positive correlations between TC and TG or LDL-cholesterol. Energy intakes were correlated positively with TIBC(p＜0.05), and vitamin C intakes negatively correlated with Hb(P＜0.05). And vitamin A intakes were negatively correlated with TG(p＜0.01). TC(p＜0.05) and LDL-Chol(p＜0.01). Hb negatively correlated with TG(P＜0.05). Body weights(p＜0.05), lean body mass(p＜0.05) and total body water(p＜0.01) werenegatively correlated with Hb. BMI and WHR correlated with TG and TC(p＜0.01). These results indicated that subjects with higher energy intake and overweight had a tendency to have iron deficiency. Increases in BMI and WHR were related to increases in serum lipids levels and decreases in TIBC. The results also showed that serum lipids were decreased when vitamin A and iron intakes were sufficient.

• 한국버섯학회지
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• 제9권3호
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• pp.116-122
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• 2011

식용버섯으로서 버들송이버섯의 우수성을 검증하고 재배면적과 소비의 확대보급을 위하여 일반성분, 무기성분, 총 폴리페놀 함량 그리고 전자공여능 등 몇가지 생리활성을 측정하였다. 일반성분은 조단백질이 38.3%로 높게 나타났으며, 무기성분은 K, P, Mg, Mn 및 Na 순으로 높게 나타났다. 총 폴리페놀 함량은 열수추출물은 $65.2{\mu}g/m{\ell}$, 에탄올 추출물은 $46.0{\mu}g/m{\ell}$ 이었으며, 플라보노이드 함량은 열수추출물에서 $12.5{\mu}g/m{\ell}$, 에탄올 추출물에서 $7.1{\mu}g/m{\ell}$ 이었다. DPPH radical 제거 활성은 열수추출물에서 58.2%, 에탄올 추출물에서 79.2%의 free radical 제거활성을 보여 열수 추출물보다는 에탄올 추출물에서 항산화활성이 높았다. 버들송이버섯 추출물의 총 폴리페놀함량, 플라보노이드 함량 그리고 DPPH radical 제거 활성은 큰느타리버섯 또는 느타리버섯보다 함량이 많고 항산화활성이 높은 것으로 조사되었다. Tyrosinase 저해활성은 열수 추출물은 63.2%, 에탄올 추출물에서는 65.0%의 저해활성을 나타내어 추출용매에 따른 큰 차이는 보이지 않았다. ACE 저해활성은 열수 추출물은 78.7%, 에탄올 추출물은 75.0%의 저해활성을 나타내어 열수 추출물에서 다소 높은 경향이었다. 이러한 결과로 볼 때 버들송이 버섯은 큰느타리버섯이나 느타리버섯 보다 폴리페놀 물질과 같은 항산화성분이 많고, 생리활성이 우수하여 식용버섯으로의 가치가 충분한 것으로 나타났다.