• 한국환경과학회지
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• 제8권4호
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• pp.443-449
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• 1999

This paper describe the working of algal culture system under batch and continuous feeding effluents in biological treatment process. The main objective of this study was the determination of fundamental opeating parameters such as dilution rates, light intensity, biomass concentration, nutrients contents, which engender an effective nutrient and organic waste removal process. The results of this research indicate that the algae system will remove effectively nutrient and organic waste. In batch cultures, 91.8% dissolved orthophosphate and 83.3% ammonia nitrogen were removed from the sewage in ten days. In continuous flow systems, a detention time of 2.5 days was found adequate to remove 91% T-P, 87% T-N and 95% $NH_3-N$. At 22-28$^{\circ}C$, 60 rpm, with an intensity of 3500 Lux, the specific growth rate, k was 0.59/day in batch experiments. The optimal growth temperature and nutrients rate (N/P) were respectively $25^{\circ}C$ and 3~5. With an abundant supply of untrients, it was possible to sustain substantial population densities in the temperature range of 22~28$^{\circ}C$.

• 생물환경조절학회지
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• 제8권2호
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• pp.90-98
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• 1999

양액재배시 적합한 배지와 배양액농도를 선발하고자 본 실험을 수행하였으며, 공시작물은 백리향(Thymus vulgaris L.)으로 하였다. 배양액의 농도는 European Vegetable R&D Center에서 개발한 herb 배양액(EC=2.4)을 0.5, 1, 2, 3배로 조제하여 사용하였다. 배지는 고형배지로 펄라이트 단용, 코코피트 단용 그리고 펄라이트와 코코피트 혼용(50:50 v/v)을 사용하였고, 비고형배지로는 DFT를 사용하여 총 4처리로 하였다. 생육은 다른 배지 처리구보다 담액수경에서 가장 좋았다. 펄라이트와 담액수경에서는 배양액농도가 높을수록 생육이 감소하였으나 코코피트는 1배, 혼용 배지는 2배 처리구에서 가장 높은 생체중을 보였다. 엽록소와 비타민 C의 함량 또한 다른 배지 처리구보다 담액수경에서 더 높은 함량을 보였다. 배지의 종류에 따른 무기물 함량은 NO$_{3}$-N과 Mg를 제외하고 모두 코코피트에서 가장 높은 함량을 나타내었다. NO$_{3}$-N의 함량은 담액 수경에서 1000 ppm 내외의 낮은 함량을 보였다. 따라서 본 실험의 결과, 백리향의 생육은 DFT를 사용하여 herb배양액 0.5배(EC =1.2mS/cm)농도로 재배한 처리구에서 가장 좋은 생육을 보였다.

• 대한지역사회영양학회지
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• 제11권5호
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• pp.587-597
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• 2006

This study was performed in order to identify nutritional factors affecting on skin sebum content with 131 female university undergraduates in 2003. We measured the sebum contents of 4 facial spots to classify their skin types. Daily energy and nutrient intakes of the subjects were not deficient except in calcium and iron, which were 466.2 mg (66.6% RDA) and 8.5 mg (53.4% RDA) relatively. We observed no significant difference of energy and nutrient intakes among the 3 skin types. But significantly higher consumption of grains and slightly higher frequencies of several food groups (excepting starches) were shown in oily skin types, so they might have higher nutrient intakes. Serum indices and food preferences mostly revealed no difference among the 3 skin types. But in the oily skin type, serum phosphorus levels were significantly lower than others, suggesting phosphorus-rich food consumption like soft drinks and pains could lead to a dry skin type rather than an oily one. Also in the oily skin type, sweet taste preference was slightly tower than others; more-over, sweet intake was lower samely significantly. There was mostly no significant relationship between facial sebum contents and nutrient intakes, dietary behavior, food frequency and food preference except in some factors. Animal protein intake showed a significant negative relationship toward facial sebum content. On the other hand, in normal skin type, Fishes consumed was slightly higher than others, so that higher animal protein consumption presumably leads to normal skin type. Frequency of fried food and bacon and preference of fried foods showed slightly negative relationships toward facial sebum content. Regular meal times showed significantly increased facial sebum content.

• Journal of Ecology and Environment
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• 제29권5호
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• pp.469-478
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• 2006

The composition changes of litters were investigated to figure out the effects of the decomposition of Humulus japonicus on nutrient circulation and decomposition process in the riverine wetlands: Tan stream and Amsa-dong. Litterbags (mesh size 1 mm and 5 mm) were installed to monitor mass and nutrient changes of 5 types of litters: H. japanicus only, Miscanthus sacchariflarus only, Phragmites communis only, mixed litters including H. japonicus, and mixed litters without H. japonicus for 7 months. It was shown that k (decay rate) of the H. japanicus ($2.68{\sim}3.12$) was higher than that of M. sacchariflorus ($1.83{\sim}2.16$) and P. communis ($0.02{\sim}1.18$). The mass and organic remainings of the mixed litters including H. japonicus at Tan stream were $47.0{\sim}55.1%\;and\;47.0{\sim}54.9%$ and those of the litterbags without H. japanicus were $49.2{\sim}65.4%\;and\;47.1{\sim}57.5%$, respectively. This result indicated that the nutrient circulation was faster at H. japanicus community than others. Ca, Na, Mg, K, P, C, N and H contents reduced to around $40{\sim}80%$ of original. However, Na concentration increased up to $407{\sim}584%$ at 100 days and decreased to $248{\sim}498%$ at the end of the experiment. Decomposition rates were similar between 1 mm and 5mm mesh size litterbags and this implies that plant litters in studied areas decomposed mainly by microbes rather than small animals. This study revealed that the fast growth of H. japonicus was resulted from fast decomposition in part: positive feedback of nutrient cycling.

• 농업과학연구
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• 제49권3호
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• pp.629-641
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• 2022

This research was conducted to secure fundamental data for development of a recirculating hydroponic system. To achieve this, Lycopersicum esculentum var. 'Dafnis' and 'TY Tiny' were grown with Yamazaki hydroponic solution and the inorganic element concentrations of plant leaves and nutrient solution of supplied and drained were analyzed periodically. The T-N and P contents in both varieties of tomato leaves showed gradual decreasing tendencies with the passage of time. The 'TY Tiny' tomato had higher contents of those two nutrients than 'Dafnis' tomato in the late stage. The K content of 'Dafnis' tomato was high in the early growth stage, but low in the late stage. However, that of 'TY Tiny' tomatoes rose in the late stage. The Ca content gradually increased in both varieties of tomato in the latter stages. The EC of the drained nutrient solution in both varieties of tomato showed increasing tendencies as time had passed, but the pH was get lowered in the drained solution. The concentrations of NO₃-N, K, Ca, Mg, Na, Fe, and B, except PO₄-P in the drained nutrient solution were generally higher than those in the supplied solution, especially in the period of October through December. The above results can be used for controlling of nutrient concentrations in the recirculated hydroponic cultivation of tomato.

• 현장농수산연구지
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• 제18권1호
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• pp.37-45
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• 2016

In order to obtain the optimum application time of liquid pig manure (LPM) for growth and nutrient contents of green manure crops (GMCs), the growth and nutrient characteristics of GMCs were evaluated under different application times of LPM in pot experiment. GMCs were sown in Sept. 1, 2012. LPM was treated in soil surface at 15 days before sowing (15DBS), at 0 days after sowing (ASD) and at 25 days after sowing (25DAS). At 60 days after seeding, plant heights of barley and hairy vetch were higher in 15DBS treatment than those in other treatments. Biomass of barley was higher in the order of 15DBS (50.2g plant^-1) > ASD (49.8g plant^-1) > 25DAS (48.5g plant^-1) > control treatment (37.5g plant^-1). Biomass of hairy vetch in 15DBS treatment was higher than that in other treatments. Nutrient contents of barley and hairy vetch were not different regardless of LPM application times. On the other hand, the amounts of nutrients uptake in 15DBS treatment were higher than those in other treatments. Therefore, in considering growth status and nutrient contributions of GMC, the optimum application time of LPM was 15DBS.

• 대한영양사협회학술지
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• 제11권1호
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• pp.114-124
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• 2005

The nutritional status of pre-school children is important for both physical growth and functional development. This study investigated the anthropometric, nutrient intakes and dietary quality of the pre-school children living in Asan for planning nutritional education program. The dietary intakes were measured by 2-day 24 hr recall recorded by children's mothers and the anthropometric data were collected by measuring children's weights, heights, and percent body fat at Asan Public Health Center. The children were 161 boys and 129 girls aged 5 and 6 years. When children's nutritional status was determined by their anthropometric status (underweight, normal weight and overweight) determined by z-score (normal range between -1.00 and 1.00), only 1.4% of the children belonged to underweight group while 55.7% and 42.9% belonged to normal and overweight groups, respectively. Significantly higher number of children belonged to overweight group for 5 year-olds. No differences were observed in nutrient intakes, nutrient adequacy ratio (NAR) and index of nutritional quality (INQ) values among nutritional status groups. Intakes of the most nutrients were adequate, but NAR and INQ of calcium and zinc were low. When nutrient intakes, NAR and INQ were compared by sex or age, all nutrient intakes were appropriate except calcium and zinc intakes of 6 year-olds. Nutrient intakes of 5 years were higher than those of 6 years. The mean of nutrient adequacy ratio (MAR) was 0.85 and mean INQ was 1.51 for all participants. The nutritional management program for pre-school children in Asan would be directed differently by age groups and education material should contain contents educating to consume moderate amount of food for 5 year-olds and to increase intake of foods with mineral nutrients such as calcium and zinc for 6 year-olds.

• Asian-Australasian Journal of Animal Sciences
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• 제29권4호
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• pp.549-554
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• 2016

The present study was conducted to investigate whether dietary essential oils could affect growth performance, relative organ weights, cecal microflora, immune responses and blood profiles of broiler chickens fed on diets containing different nutrient densities. A total of eight hundred-forty 1-d-old male broiler chicks were randomly allotted into twenty-eight pens (7 pens per treatment, 30 chicks per pen). There were four experimental diets containing two different nutrient densities and supplemented with or without essential oils. Experimental period lasted for 35 days. No clear interaction between nutrient density and essential oils on any of growth performance-related parameters was observed. Live body weights were affected (p<0.05) by nutrient density at 21 days and by dietary essential oils at 35 days. Essential oils significantly (p<0.05) increased daily body weight gain and feed conversion ratio during the periods of 22 to 35 and 1 to 35 days, but failed to affect feed intake during the entire experimental period. Daily weight gain at 1 to 21 days and feed intake at 1 to 21 and 1 to 35 days were significantly impaired (p<0.05) by nutrient density. There were significant treatment interactions (p<0.05) on relative weights of bursa of Fabricius and abdominal fat contents. Finally, either essential oil or nutrient density did not influence the relative percentages of breast and leg meats, the population of cecal microflora, blood parameters and antibody titers against Newcastle disease and infectious bronchitis in broiler chickens. It was concluded that dietary essential oils, independent to nutrient density, failed to stimulate feed intake, but increased growth performance in broiler chickens.

• 한국수산과학회지
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• 제51권3호
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• pp.221-229
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• 2018

Various types of dried laver Pyropia yezoensis have been produced in response to increasing demand and other laver goods manufactured using different processing methods are continuously being developed. The dried laver used in this experiment was initially heated at $165^{\circ}C$ for 3 seconds, followed by second heating at a high temperature ($340-350^{\circ}C$) to increase the storage period and enhance taste and flavor. Nutrient analysis of each sample heated under three conditions revealed that the protein and lipid contents were highest in samples from D company, while the carbohydrate contents remained relatively stable. After storage for 10 weeks at room temperature, changes in the composition were evaluated. The results showed decrease in protein (30%-49%) and essential amino acid contents. During storage, the major unsaturated fatty acids contained in dried laver slightly changed to 53.4%-56.0% in the form of EPA, while saturated fatty acids slightly increased to 18.4%-22.6% in the form of palmitic acid. The variables derived from fatty acid composition, such as atherogenic and thrombogenic, and hypocholesterolemic/hypercholesterolemic dietary indices, and polyunsaturated fatty acids/saturated fatty acids ratio, also indicated reasonable levels of stability. However, the laver should be consumed within 2 months.

• 생물환경조절학회지
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• 제5권2호
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• pp.236-247
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• 1996

본 실험은 양액의 종류와 배지의 종류, 그리고 양액의 농도가 20일 무의 생육과 몇가지 품질에 미치는 영향을 알아보고자 실시하였다. 20일 무의 양액재배시 적절한 양액의 구명을 위하여 기존의 Cooper, Hoagland, Yamazaki양액의 비교실험을 실시한 결과, YamaBaki양액이 엽장, 엽수, 지상부와 지하부 생체중 등 전반적으로 Hoagland와 Cooper 양액보다 좋은 결과를 나타내었다. 근형지수는 모든 처리구에서 약 0.66으로 비교적 낮은 수치를 보였다. 14가지 조합의 배지를 이용하여 고형배지경을 실시하였다. 그 결과 모래 배지가 가장 균일하고도 좋은 생육의 20일 무를 배출하였고, 피트모스는 반대의 생육을 보였다. 근형지수의 경우 전반적으로 고형배지경이 순수수경재배보다 높은 수치를 나타내었다. Yamazaki 양액의 적정농도 수준을 구명을 위하여 모래를 배지로 하여 20일 무의 생육과 품질을 비교 조사한 결과, 1.0mS/cm 이상의 농도에서는 전반적으로 20일 무의 생육이 좋았으며, 특히 1.5mS/cm가 가장 좋은 생육을 보였다. 비타민 C의 함량과 티오시아네이트 함량은 1.0mS/cm이상의 처리구에서는 현저한 차이가 없었으나, 0.5mS/cm는 상당히 높은 수치를 보였다. 또한 무기물 함량의 경우는 모든 처리구에서 통계적 유의성이 없었으나, 칼륨이 1.5mS/cm에서 비교적 높은 함량을 나타내었다.