• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.628-634
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• 1998

The properties of the n-type impurities nitrogen and phosphorus in diamond have been investigated by means of electronic band structure calculations within the framework of the semiempirical extended Huckel tight-binding method. For diamond with the nitrogen and phosphorus substitutional impurities, calculated density of states shows the impurity level deep in the band gap. This property can be derived from the substantial <111> relaxation of the impurity and nearest-neighbor carbon atoms, which is associated with the population of an antibonding orbital between them. The passivated donor property of the P-vacancy complex which lies deep in the gap is also discussed.

• Korean Journal of Community Nutrition
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• v.25 no.6
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• pp.485-501
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• 2020

Objectives: The purpose of this study was to examine the biochemical characteristics and dietary intake of adolescents aged 12 to 18 years according to the frequency of milk consumption. Methods: Data from the 2010~2011 Korea National Health and Nutrition Examination Survey was used for the study. The study examined adolescents' (12~18 years) demographic characteristics (house income level, residence region, skipping or not-skipping of breakfast/lunch/dinner, eating-out frequency), anthropometric characteristics (height, weight, weight status), biochemical characteristics (fasting plasma glucose, blood urea nitrogen, creatine, triglycerides, cholesterol, HDL-cholesterol, hemoglobin, hematocrit) and nutrient intakes through quantitative and qualitative evaluation using the Korean Dietary Reference Intakes (KDRI), index of nutrition quality (INQ), nutrition adequacy ratio (NAR) of 3 groups (< 1/week, 1~6/week, ≥ 1/day) according to the frequency of milk consumption. Results: There were significant differences in gender and income levels among the 3 groups. There were no differences in height, weight, and weight status among groups. There were differences in biochemical characteristics and nutrient intake. In boys, there were differences in the mean of BUN and HDL-cholesterol, in quantitative intakes of riboflavin, calcium, phosphorus, potassium by KDRI levels, in qualitative intakes of riboflavin, calcium, phosphorus by INQ and riboflavin, calcium, phosphorus by NAR among 3 groups. In girls, there were differences in the mean of blood urea nitrogen, creatine, HDL-cholesterol, in quantitative intakes of protein, riboflavin, calcium, phosphorus by KDRI levels, in qualitative intakes of riboflavin, calcium, phosphorus by INQ and riboflavin, calcium, phosphorus by NAR among the 3 groups. Conclusions: In Korean adolescents, boys had a higher frequency of milk consumption than girls, and higher the income level, higher the frequency of milk consumption. Consumption of milk appeared to have a positive association with triglycerides, HDL-cholesterol, and indices related to muscle mass. Regular consumption of milk is an important factor in enhancing the intake of riboflavin, calcium, and phosphorus, which adolescents lack. The results of the study indicate a need to prepare an environment and education program to increase milk consumption in adolescents at home and school.

• Journal of radiological science and technology
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• v.9 no.1
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• pp.137-143
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• 1986

This study was undertaken to analyze the changes of radiographical image in avian (chicken) by using scanner and ${\gamma}-camera$ with $Tc^{99m}-MDP$. Experiment was aimed also to observe the changes of calcium, phosphorus and alkaline phosphatase activity in serum after experimental fracture. The results obtained are summerized as follows. 1. 10 chickens grown 6 weeks were scanned within 48 hours after experimental fracture, showed localized increase in uptake. The earlist increased local uptake was observed after 7 hours from experimental fracture at the fracture site. 2. Serum alkaline phosphatase level was increasing continuously during the fracture healing process in comparison with control group and serum alkaline phosphatase activity showed a peak after 2 weeks following the fracture. 3. The change of Ca. amount in serum trended to decrease from 1st day after fracture and it was in the lowest level at the 7 day's group following the fracture. 4. Serum phosphorus level trended to increase after fracture and it was in the highest level at the 7 day's group and showed similar level in comparison with control group.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.120.1-120.1
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• 2015

We investigate the degradation pattern of Black phosphorus (BP) field effect transistor (FETs) investigated by using an mechanically exfoliated BP that react O2 and water vapor in ambient condition, degradation. The BP FETs was electrically measured every 20 minutes (1cycle) in the air, the total cycle is 100. We show electrical changes with Mobility, On/off ratio, Current and a significant positive shift in the threshold voltage. We extracted the current level at Vgs-Vth = 0, -10, -20 and fitting with Swiss-cheese model. This model suggested that Swiss-cheese model is well fitted with degradation pattern of BP FETs.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.167.1-167.1
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• 2015

We investigate the degradation pattern of Black phosphorus (BP) field effect transistor (FETs) was investigated by using an mechanically exfoliated BP that react O2 and water vapor in ambient condition, degradation. The BP FETs was electrically measured every 20 minutes (1cycle) in the air, the total cycle is 100. We show electrical changes with Mobility, On/off ratio, Current and a significant positive shift in the threshold voltage. We extracted the current level at Vgs-Vth = 0, -10, -20 and fitting with Swiss-cheese model. This model suggested that Swiss-cheese model is well fitted with degradation pattern of BP FETs.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.124-135
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• 2003

In order to prevent pollution from animal waste, the excretion of nutrients should be reduced through proper nutritional management. Among the many nutrients of concern, such as N, P, Cu, Zn and K, P is one of the most concerned nutrients to be managed. Seven feeding trials, three with layers and four with broilers, were conducted to determine if microbial phytase supplementation can reduce non-phytate phosphorus (NPP) level in diets and results in concomitant reductions of P excretion. The results showed that microbial phytase can be successfully used to achieve these purposes. Activity of natural phytase in certain plant feedstuffs is high enough to be considered in feed formulation. Three experiments have been conducted to study the characteristics of plant phytase and its application to feeding of broilers. Selected brands of wheat bran could be successfully used as a source of phytase in broiler feeding.

• Korean Journal of Ecology and Environment
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• v.40 no.4
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• pp.511-519
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• 2007

It is known that phytoplankton biomass or turbidity are lower in waters with submerged macrophytes than those without submerged plants at a given nutrient level. We hypothesize that presence of submerged macrophytes would lower phytoplankton biomass below levels expected by total phosphorus levels through various mechanisms and that phytoplankton biomass would decrease more as the biomass increase of the submerged macrophytes. To find submerged macrophytes effectively lowering phytoplankton growth, we conducted spatial field surveys at 21 water bodies and a temporal monitoring at Seung-un 1 Reservoir, Anmyyeondo Island. We measured chlorophyll ${\alpha}$ concentrations and total phosphorus (TP) concentrations from waters in patches of submerged macrophytes with measurements of submerged plant biomass. Majority of our sites with submerged macrophytes showed much less chlorophyll a concentrations than the predicted ones from literature. Among submerged macrophytes studied, Myriophyllum spicatum and Hydrilla verticillata showed patterns of lowering chlorophyll ${\alpha}/TP$ ratios with increase of their biomass in both spatial and temporal surveys.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.4
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• pp.181-190
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• 2001

This study was conducted to investigate the effect of swine liquid manure(SLM) and phosphorus fertilizer from September, 1998 to July, 1999 on the soil fertility on Italian ryegrass field, Cheju volcanic ash soil. pH(lst investigated), Mg (2nd investigated) and Cu content (2nd investigated) on soil grown by Italian ryegrass were significantly increased by an increase of fertilizer P(P

• Korean Journal of Environmental Biology
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• v.27 no.3
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• pp.306-313
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• 2009

In the Upo wetland, physico-chemical factors were observed during the period from March 2005 to December 2007 on a monthly basis. In the Upo wetland, water temperatures ranged $3.4{\sim}34.5^{\circ}C$. Conductivities were in the range of 133~806 ${\mu}S\;cm^{-1}$, which showed about 140 ${\mu}S\;cm^{-1}$ below in comparison with the precedent studies. The pH levels were between 6.7~9.1 with lower level in summertime. The dissolved oxygens were between 0.06~18.23 mg $L^{-1}$. COD ranged 4.9~20.8 mg $L^{-1}$, and showed a tendency to decrease every year. Nitrogen nutrients such as nitrate nitrogen ($NO_3-N$), ammonia nitrogen ($NH_3-N$) and total nitrogen (T-P) showed that they were generally decreased in comparison with those in the precedent studies. However the total nitrogen (T-N) is still considerably higher than the standard concentration level of eutrophication and algal blooming. Phosphate phosphorus ($PO_4-P$) and total phosphorus (T-P) were also shown as to be reduced considerably comparing with the values in the precedent studies. However, It was found out that total phosphorus (T-P) was dissolved over the criteria concentration of eutrophication. The average of TN/TP ratio was 18 in the Upo wetland, which proved that phosphorus was the limiting factor to the growth of phytoplankton in the Upo wetland. The chl-$\alpha$ was the highest in wintertime and the lowest in summertime, and especially in 2006 summer when the cyanobacterial bloom developed, it showed extremely high concentration.

• Korean Journal of Medicinal Crop Science
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• v.18 no.4
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• pp.273-279
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• 2010

The study result survey platycodon cultivation regions of Jinju(2), Sacheon(4), Hapcheon(3), Haman(3), and Sancheong(3) of Gyongnam regarding chemical properties of soil, inorganic nitrogen phosphorus by type of composition is as follows: pH and EC value were highest where platycodon cultivated for under 3 years in soils. Content of O.M equal to or less than 25 mg $kg^{-1}$, the average value for platycodoncultivation in korea. Content of exchangeable calcium in soils were 12, 14 $cmol^+kg^{-1}$ in Hapcheon and Haman regions where platycodon was cultivated for two years which is 2~3 time higher level compared with the average upland soil of korea. Water solution boron confirmed approximated level of 3.0 mg $kg^{-1}$ in all survey regions, and the finding is about five times higher than average upland soil of korea which is 0.5 mg $kg^{-1}$. In the case of nitrogen, a significant difference was found depending on cultivation regions and continuous culture. Content of nitrogen in soils were difference according to cultivation area and continuous culture. The composition ratio according to the type of inorganic phosphorus showed the highest in order of Al-P > Ca-P > Fe-P > Saloid-P in all survey regions except for Hapcheon (five, seven years cultivated soils). The correlation showed high significance between available phosphate and inorganic phosphorus.