• Journal of Environmental Health Sciences
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• v.27 no.3
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• pp.81-85
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• 2001

The aim of this study was to evaluate on the removal effect of total nitrogen and posphorus in municipal wastewater by decreasing hydraulic retention time(HRT) from 6 hour to 4 hour on CNR process using influent as a Carbon Source. CNR(Cilium Nutrient Romoval) is the process combining $A^2$/O process with cilium media of H2L corporation. The removal efficiencies for BOD$_{5}$, T-N and T-P were 81.1%, 61.4%, 61.4%, respectively. The removal efficiency of nitrogen and posphorus were low by decreasing hydraulic retention time(HRT) from 6 hour to 4 hour on CNR process.s.

• Journal of Veterinary Clinics
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• v.18 no.1
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• pp.18-21
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• 2001

In this study, we assessed the efficacy of a novel B. amyloliquefacience DS11 phytase (DS11 phytase) and that of a commercial Aspergillus ficcum phytase (AF phytase) through their bioavailabilities of phytin-posphorus and -calcium in the diet using cannulated pigs. For the purpose of evaluating the efficacy of the phytases in pigs, we determined phosphorous concentrations from serum and feces, in addition to ingesta obtained from the cannula at the terminal ileum. As results, phosphorus concentration was lower in feces from DS11 group and BASF group by 17% and 10%, and higher in serum from the respective groups by 34% and 20%, as compared to the control group. Both phytases are evaluated to enhance phosphorus availability to the great extent. Calcium concentration of feces were lower in DS11 group and BASF group by 31% and 10%, than that in the control. Calcium concentration of serum was higher in DS11 phytase group by 4% but lower in AF phyase group by 3%, then that in the control group.

• Journal of the Korean Vacuum Society
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• v.4 no.3
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• pp.293-300
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• 1995

p-doped poly-Si/SiO2/Si 기판위에 저압 화학증착법(LPCVD)으로 증착한 텅스텐 실리사이드(WS2.7)막을$ 850^{\circ}C$에서 20분 동안 N2 분위기에서 열처리한 후에 건식 분위기에서 열산화하였다. 다결정 실리콘의 인도핑(doping)레벨에 따른 텅스텐 폴리사이드(WSi2.5/poly-Si)막의 산화 성장률과 텅스텐 폴리사이드막의 산화 메카니즘에 대하여 연구하였다. 텅스텐 폴리사이드막의 산화 성장률은 다결정 실리콘의 인(p) 도핑 레벨이 증가함에 따라 증가하였다. 텅스텐 폴리사이드막의 산화는 텅스텐 실리사이드층의 과잉(excess)Si가 초기 산화과정 동안 소모된 후에 다결정 실리콘층의 Si가 소모되었다. 산화막과 산화막을 식각(etching)한 후에 텅스텐 실리사이드막의 표면 거칠기는 다결정 실리？의 인 농도가 적을수록 평탄하였다.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05b
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• pp.129-132
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• 2001

The purpose of this research was to understand possibility of foodwaste treatment by hybrid anaerobic reactor(HAR). The Possibility of methane utility and applicability of hybrid reactor system using foodwaste as substrate was investigated. The maximum loading rate and optimized operational conditions were determined. Hybrid anaerobic reactor was filled with packing material 50% of its total volume between the tube and the outer surface. The packing material used was randomly packed open-pore synthesis activated ceramic(SAC) media as support media for microbial attachment, growth, and chemical stability protected bacteria from effect of organic acid accumulation. In this research, although foodwaste has high concentrations C $l^{[-10]}$ and S $O_{4}$$^{2-}$ concentration the possibility of foodwaste anaerobic treatment was when foodwaste is treated by anaerobic digestion, this study focused on the possibility using C $H_4$ gas made under the anaerobic treatment as an alternative energy source. Other objective of this research is to study struvite formation and crystal forms in anaerobic digester. HAR is used to investigate phosphate crystallization without the addition of chemicals.

• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.319-324
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• 2014

An 8 weeks feeding trial was carried out to evaluate the effects of dietary microbial phytase (P) supplementation on nutrient digestibility, and body composition in juvenile olive flounder Paralichthys olivaceus fed soybean meal-based diets. Seven experimental diets were formulated to be isonitrogenous and isocaloric to contain 50.0% crude protein (CP) and 16.7 kJ of available energy/g with or without dietary phytase supplementation. White fish meal (FM) provided 92.4% of the total protein in the basal diet ($S_0$), in the other 6 diets, 30% or 40% FM protein was replaced by soybean meal: 70% FM + 30% soybean meal ($S_{30}$); 70% FM + 30% SM + 1000 U phytase/kg diet ($S_{30}P_{1000}$); 70% FM + 30% SM + 2000 U phytase/kg diet ($S_{30}P_{2000}$); 60% FM + 40% SM ($S_{40}$); 60% FM + 40% SM + 1000 U phytase/kg diet ($S_{40}P_{1000}$); and 60% FM + 40% SM + 2000 U phytase/kg diet ($S_{40}P_{2000}$). After two weeks of the conditioning period, triplicate groups of 25 fish initially averaging $6.15{\pm}0.04g$ ($mean{\pm}S.D.$) were randomly distributed into the aquarium and were fed one of the experimental diets for 8 weeks. After feeding trial, supplementation of phytase significantly improved the apparent digestibility coefficients of phosphorus in flounder diets (P<0.05) containing 30% and 40% soybean meal regardless the levels. However, phytase had no significant influence on growth performance and whole body composition of fish. Based on the experimental results, we conclude that dietary supplementation of phytase could improve the apparent digestibility coefficient of phosphorus in olive flounder.

• Korean Journal of Soil Science and Fertilizer
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• v.2 no.1
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• pp.53-68
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• 1969

The nutriophysiological response of rice plant to root environment was investigated with eye observation of root development and rhizosphere in situation. The results may be summarized as follows: 1) The quick decomposition of organic matter, added in low yield soil, caused that the origainal organic matter content was reached very quickly, in spite of it low value. In high yield soil the reverse was seen. 2) In low yield soil root development, root activity and T/R value were very low, whereas addition of organic matter lowered them still wore. This might be contributed to gas bubbles around the root by the decomposition of organic matter. 3) Varietal difference in the response to root environment was clear. Suwon 82 was more susceptible to growth-inhibitine conditions on low-yield soil than Norin 25. 4) Potassium uptake was mostly hindered by organic matter, while some factors in soil hindered mostly posphorus uptake. When the organic matter was added to such soil, the effect of them resulted in multiple interaction. 5) The root activity showed a correlation coeffieient of 0.839, 0.834 and 0.948 at 1% level with the number of root, yield of aerial part and root yield, respectively. At 5% level the root-activity showed correlation-coefficient of 0.751, 0.670 and 0.769 with the uptake of the aerial part of respectively. N, P and K and a correlation-coefficient of 0.729, 0.742 and 0.815 with the uptake of the root of respectively N.P. and K. So especially for K-uptake a high correlation with the root-activity was found. 6) The nitrogen content of the roots in low-yield soil was higher than in high-yield soil, while the content in the upper part showed the reverse. It may suggest ammonium toxicity in the root. In low-yield soil Potassium and Phosphorus content was low in both the root and aerial part, and in the latter particularly in the culm and leaf sheath. 7) The content of reducing sugar, non-recuding sugar, starh and eugar, total carbohydrates in the aerial part of plants in low yield soil was higher than in high yield soil. The content of them, especially of reducing sugar in the roots was lower. It may be caused by abnormal metabolic consumption of sugar in the root. 8) Sulfur content was very high in the aerial part, especially in leaf blade of plants on low yield soil and $P_2O_5/S$ value of the leaf blade was one fifth of that in high yield soil. It suggests a possible toxic effect of sulfate ion on photophosphorization. 9) The high value of $Fe/P_2O_5$ of the aerial part of plants in low yield soil suggests the possible formation of solid $Fe/PO_4$ as a mechanical hindrance for the translocation of nutrients. 10) Translocation of nutrients in the plant was very poor and most nutrients were accumulated in the root in low yield soil. That might contributed to the lack of energy sources and mechanical hindrance. 11) The amount of roots in high yield soil, was greater than that in low yield soil. The in high-yield soil was deep, distribution of the roots whereas in the low-yield soil the root-distribution was mainly in the top-layer. Without application of Nitrogen fertilizer the roots were mainly distributed in the upper 7cm. of topsoil. With 120 kg N/ha. root were more concentrated in the layer between 7cm. and 14cm. depth. The amount of roots increased with the amount of fertilizer applied.