• Journal of Environmental Science International
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• v.9 no.3
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• pp.267-273
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• 2000

In order to understand the impact for decomposition of blue-green algae Microcystis on water quality, the algae were cultivated with collection of natural population during approximately one month, when water-bloom of Microcystis dominated at August 31, 1999 in the lower part of the Okchon Stream. The enrichment of inorganic NㆍP nutrients didn't in algal assay and the effect of Microcystis on water duality was assessed from the variation of nutrients by algal senescence. Microcystis population seemed to play a temporary role of sink for nutrients in the water body. Initial algal density of Microcystis was 2.3×10/sup 6/ cells/㎖. When Microcystis population died out under light condition, algal NㆍP nutrients between 9∼12 days affected to increase of biomass after reuse by other algal growth as soon as release to the ambient water. However, cellular nutrients under dark condition were almost moved into the water during algal cultivation. NH₄, NO₃ and SRP concentration were highly increased with 160, 17 and 79 folds, respectively relative to the early. As a result, the senescence of Microcystis population seemed to be an important biological factor in which cause more eutrophy and increase of explosive algal development by a lot of nutrients transfer to water body. There are significantly observed an effort of reduce for production of inner organic matters such a phytoplankton as well as load pollutants from watershed in side of the water quality management of reservoir.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.1
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• pp.99-104
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• 2016

This study was performed to develop a new process technology for advanced wastewater treatment using a modified Rotating Activated Bacillus Contactor (RABC) process that adopts anoxic-oxic suspended biomass tanks to enhance nutrients removal. A modified lab-scale RABC process was applied to examine its applicability and to obtain the design factors for the optimum operation of the system. The modified RABC process showed a little more stable and high nutrients removal efficiency than the prototype RABC process: about 70% of nitrogen and 55% of phosphorous removal when the low organic loading (influent COD 200mg/L). However, the processing efficiency of nutrients removal rates was enhanced to great extent when high organic loading: nitrogen 90% and phosphorous 85% (influent COD 500mg/L). High organic loading stimulated extremely good biomass attachment on the reticular carrier RABC stage and the excellent nutrients removal, nevertheless with almost no offensive odor.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.3
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• pp.53-59
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• 2018

When manufacturing self-healing concrete using bacteria, nutrients are added to increase the activity of the bacteria. Although many researches have focused on the effects of nutrients containing bacterial healing agent on concrete, few have studied the effects of sole nutrient on self-healing of cement composites. Bacterial nutrients, like commercial chemical admixtures, affect hydration characteristics such as flow, setting, hydration heat, mechanical strength of cement composites and also affect the self healing of cement composites by hydration of unhydrated particles. In this study, effect of the four nutrient commonly used in the existing literature on the hydration characteristics of cement composites by its addition was investigated. Flow, setting time, hydration heat, compressive strength have studied for each nutrients added by 1.5% and 3% of cement weight. Experimental results shows that urea and calcium-nitrate can be used up to 3% without significant detrimental effect on cement composites. Addition of calcium-lactate up to 1.5% show better compressive strength than control, but addition of 3% show almost non-hydration. Yeast extract shows detrimental effects on the composites regardless of the amount added.

• Journal of Environmental Science International
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• v.6 no.2
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• pp.141-152
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• 1997

The pilot plant had been made so as to be an association system from the various items managed to have degrees of efficiency and It have been done to consider the experimental result with irradiance period and pH influence of all major things to treatment function of Waste Stabilization Pond. The results are as following. The attained results for continuous & cyclic irradiance 1. 24L.-reactor was prior to 12L.-12D.-reactor on oxygen generation & algal production ability. 2. 24L.-reactor was prior to 12L.-12D.-reactor on nutrients removal efficiency. 3. In 24L.-reactor it maintained 5mg/L∼6mg/L, DO concent enough to a fish's survival. The attained results for pH condition 1. Oxygen generation ^ algal production in pH 4-reactor were higher than those in pH 10-reactor. 2. The acidic condition at pH 4 and alkalic condition at pH 10 did not so much affect an algal growth and nutrients removal. The attained results for whole 1. In view of the results appeared as [(NH3-N)+(NO3-N)] removal efficiency, 89.1%∼93.9% and PO4-P removal efficiency, 34.3%∼83.7% & COD removal efficiency, 88.5%∼93.9%. It is possible to treat the wastewater with starch and pH which have been known as thedifficult problem. 2. At the point of non using methanol to nitrificate NO3-N, the nutrients removal method by using an algal growth is the most economical method in the whole nutrients removal methods. 3. The nutrients removal method by using an algal growth contributes to natural ecosystem. 4. The nutrients removal method by using an algal growth is excellant in the prevention against the eutrophication.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.833-843
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• 1998

It is noted that the red tides and the oxygen-deficient water mass are extensively developed in Masan Bay during summer. The nutrients mass balance was calculated in Masan Bay, using the three-dimensional numerical hydrodynamic model and the material cycle model. The material cycle model was calibrated with the data obtained on the field of the study area in June 1993. The nutrients mass balance calculated by the combination of the residual currents and material cycle model results showed nutrients of surface and middle levels to be transported from the inner part to the outer part of Masan Bay, and nutrients of bottom level to be transported from outer part to inner part of Masan Bay. The uptake rate of DIN in the box A1(surface level of inner part) was found to be 337. 5mg/$m^3$ㆍday, the largest value in all 9 boxes and that of DIP was found to be 18.6mg/$m^3$ㆍday in box A1, and the regeneration rate of DIN was found to be 78.2mg/$m^3$ㆍday in the box A3(bottom level of inner part), and that of DIP was found to be 18.6mg/$m^3$ㆍday in box A1. The regenerations of DIN and DIP in the water column of the entire Bay were found to be 7.66ton/day and 760kg/day, respectively. And the releases of DIN and DIP from the sediments of the entire Bay were found to be 2.86ton/day and 634kg/day, respectively. The regeneration rate was 2.5 times as high as the release rate in DIN, and 1.2 times in DIP. The results of mass balance calculation showed not only the nutrients released from the sediments but the nutrients regenerated in water column to be important in the control and management of water quality in Masan Bay.

• Ocean Science Journal
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• v.41 no.3
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• pp.125-137
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• 2006

Nutrients, chlorophyll-a, particulate organic carbon (POC), and environmental conditions were extensively investigated in the northern East China Sea (ECS) near Cheju Island during three seasonal cruises from 2003 to 2005. In spring and autumn, relatively high concentrations of nitrate ($2.6{\sim}12.4\;{\mu}mol\;kg^{-1}$) and phosphate ($0.17{\sim}0.61\;{\mu}mol\;kg^{-1}$) were observed in the surface waters in the western part of the study area because of the large supply of nutrients from deep waters by vertical mixing. The surface concentrations of nitrate and phosphate in summer were much lower than those in spring and autumn, which is ascribed to a reduced nutrient supply from the deep waters in summer because of surface layer stratification. While previous studies indicate that upwellings of the Kuroshio Current and the Changjiang (Yangtze River) are main sources of nutrients in the ECS, these two inputs seem not to have contributed significantly to the build-up of nutrients in the northern ECS during the time of this study. The lower nitrate:phosphate (N:P) ratio in the surface waters and the positive correlation between the surface N:P ratio and nitrate concentration indicate that nitrate acts as a main nutrient limiting phytoplankton growth in the northern ECS, contrary to previous reports of phosphate-limited phytoplankton growth in the ECS. This difference arises because most surface water nutrients are supplied by vertical mixing from deep waters with low N:P ratios and are not directly influenced by the Changjiang, which has a high N:P ratio. Surface chlorophyll-a levels showed large seasonal variation, with high concentrations ($0.38{\sim}4.14\;mg\;m^{-3}$) in spring and autumn and low concentrations ($0.22{\sim}1.05\;mg\;m^{-3}$) in summer. The surface distribution of chlorophyll-a coincided fairly well with that of nitrate in the northern ECS, implying that nitrate is an important nutrient controlling phytoplankton biomass. The POC:chlorophyll-a ratio was $4{\sim}6$ times higher in summer than in spring and autumn, presumably because of the high summer phytoplankton death rate caused by nutrient depletion in the surface waters.

• Journal of Nutrition and Health
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• v.33 no.4
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• pp.438-453
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• 2000

The purposes of this study were to estimate nutritional intakes of the long-lived elderly and to obtain the data for establishing dietary guidelines that may be recommended for the general population for the sake of longevity. The subjects of the study were 300 elederly people of age over 85 years living in Kyungpook Sung-Ju area who had no problem in daily living. Four times of food consumption survey were carried out seasonally by the repeated 24-hr recall method for one year. Mean daily energy intakes and RDA percentage of energy intakes of the male and female subjects were estimated as 1222 kcal(67.9%) and 1047 kcal(65.4%) respectively. Mean daily intakes of nutrients were estimated as 38.3g for protein, 287mg for calcium, 5.8mg for iron, 314R.E. for vitamin A, 0.6mg for vitamin B1 and 0.43mg for vitamin B2 The mean RDA percentages of nutrients intake were 64.4% and 59.8% for protein in male and female, 39.8% for Ca, 48.3% for Fe, 44.9% for vitamin A, 60% for vitamin B1, and 35.8% for B2. The average PFC ratio of energy-yielding nutrients throughout the year in male and female were 15.1 : 15.2 : 69.7 and 13.8 : 13.2 : 73.0 respectively. The mean daily intakes of energy and most of nutreints were significantly high in winter season. The contribution of plant food sources to nutrient intakes were over 60% for protein and fat, 50% for calcium, and 70% for iron. Long-lived elderly people an Sung-Ju, Kyungpook showed considerably smaller physiques compared to the avergae Korean elderly, however their average BMI fell in normal range. The subjects were consuming much less energy and nutrients compared to the present Korean RDA for the elderly over age 75. The subject showed relatively good health state in spite of low intakes of energy and nutrients. Therefore it seems to be necessary to establish a set of new RDA for the elderly over age 8.5.

• Journal of Korean Home Economics Education Association
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• v.12 no.3
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• pp.53-63
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• 2000

The purpose of this study was quantitative and qualitative contents analysis of food and nutrition section in middle school textbooks of home economics, physical education and science. As a quantitative approach numbers of sentence lines tables, figures, photos, activities, and exercises were counted. As a qualitative approach, types of explanations were categorized by 7 criteria, and commons and differences of the contents of those subjects were compared. The conclusions of this study were summarized as follows: 1) Contents of food and nutrition section were divided into nutrients. water. energy, food groups, and nutritional problems. When average sentence lines of each were compared, those of nutrients were the longest in all 3 subjects. 2) When compared the numbers of tables, figures, and photos in 3 subjects of textbooks, there were more figures in home economics and science, and more tables in physical education. 3) There were more activities and exercises in home economics an science than in physical education. 4) The D(sentences with table) or E type(sentences with figure) was adapted for the explanation of nutrients functions, recommended dietary allowance, food sources, food groups, eating habits, and weight control in home economics: nutritions functions and energy metabolism in physical education : and digestion, body constituents, energy metabolism, and detection of nutrients in science. 5) Contents about classification and functions of nutrients. food sources deficiency water, energy contents of nutrients and obesity were shown in all 3 subjects. Food groups and eating habits were explained in detail in home economics whereas digestion of nutrients in the digestive tracts were explained in detail in science. Recommended dietary allowance for Koreans and basic food groups revised in 1995 were presented in home economics, whereas those revised in 1989 were presented in physical education. To avoid confusion, recommended dietary allowance for Koreans and food groups presented in physical education tex should be updated.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.115-120
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• 1997

The purpose of thesis was to investigate the removal efficiency of surfactants and commercial detergents by Oenanthe javanica that is one of aquatic plants in Korea. The experiment is concerned with measuring the concentrations of surfactants and commercial detergents in different media: 1) in pure water, 2) in water containing Oenanthe javanica, 3) in water containing Oenanthe javanica and commercial nutrients. The surfactants used in this research include linear alkylbenzene sulfonates (LAS), $\alpha$-sulfo fatty acid methyl esters(MES), and alkylbenzene sulfonates(ABS). Two commercial detergents designated as A and B were in the forms of power and liquid. The results showed that LAS and MES were more effectively removed by Oenanthe javanica probably because these have a chain of linear carbon than on ABS with a branched carbon structure. In the case of commercial detergents, when the except was performed on the basis of surfactants proportion, the removal trends were similar to LAS and MES. The 5-day cultivating test with initial concentration of 0.5-1.0 ppm surfactants showed that less than 10% was removed if no nutrients an Oenanthe javanica were added. When Oenanthe javanica was added into the sample solution containing surfactants, the removal efficiency was increased 100% for the solution containing 0.5-1.0 ppm 60-70% for 5-10 ppm. In addition, chlorisis on Oenanthe javanica was observed due to surfactants and commercial detergents for all three cases. To test the dependence of population density on nutrients, the initial population density was made 300 g/0.4 m$^2$. Throughout the 5-day experiment, the on Oenanthe javanica grew 20-25% with 0.5-1.0 ppm without the synthetic nutrients but by 5% with a high concentrations of 5-10 ppm. The population density was appeared to be independent of synthetic nutrients. The leaves were to be grown with synthetic nutrients, while roots were grown without synthetic nutrients. Based on this research, the fundamental data concerning cultivation and an adequate adjustment of the water condition can provide for the utilization of Oenanthe javanica in real water treatment system.

• Journal of Nutrition and Health
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• v.10 no.3
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• pp.10-24
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• 1977

The effects of dietary cellulose to utilize the intake nutrients in the albino rats were investigated by the two consecutive experiments in this study. The author wanted to observe the effects of the age of animals and different level of dietary cellulose, high and low in the first experiment and the effects of dietary cellulose from three different sources, rice bran, vegetable and pure-cellulose at high level in the second experiment. The results were summarized as follows. (1) The obvious effect of dietary cellulose caused to increase feces weight. Consequently apparent digestibilities of intake nutrients in the diet decreased. It was noteworthy that fecal glucose excretion was significantly affected by cellulose intake. Since three nutrients, protein, fat and carbohydrate serve as energy sources in the body, this result can be interpreted to be lowered in the efficiency of energy utilization out of intake from the diet. (2) The nutrients loss due to dietary cellulose resulted in reduction of skeletal muscle and bone weights which lead eventually to affect in reduction of body weight. (3) The effects of dietary cellulose showed differently according to the amount of cellulose ingested, dietary nutrients composition, the kinds of dietary cellulose supplemented and the age of experimental animals. When the intake diet was proportionately imbalanced in three different energy sources, carbohydrate, fat and protein, the cellulose intake was adversely affected in the utilization of the nutrients in the body. Cellulose from rice bran decreased body weight gain, cellulose from vegetable maintained medium level in body weight and pure-cellulose increased body weight. Growing rats showed more sensitive effects of cellulose tolerance in the body than grown rats in every concerns of this experiment.