• Proceedings of the KAIS Fall Conference
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• 2005.05a
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• pp.45-47
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• 2005

전기, 전자, 우주, 자동차, 무기 등의 여러 분야에서 응용되고 있는 고정밀, 고저항체 박막인 TaNx 다층박막을 반응성 마그네트론 스퍼터링법으로 제조하여 질소분압에 따른 TCR 특성 변화를 조사하고, XRD와 SEM 관찰을 통하여 미세조직이 전기적 성질에 미치는 영향을 알아보았다. 제조된 TaNx 박막의 전기저항은 질소분율이 증가함에 따라 저온보다 고온에서 전기저항이 감소함을 보여 뚜렷한 (-)TCR 특성을 나타내었다. XRD 분석 결과, $Ar/N_2$ 비가 0.05에서 TaN 상이 형성되고 0.1에서 우수한 결정성을 나타내었으며, $N_2$의 양이 증가할수록 비정질이 형성되었다. 박막의 표면 형상은 미세하고 불연속 아일랜드 형태로 변화하였다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.155-158
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• 2002

질산성질소 및 탁도로 오염된 지하수공에 대하여 환경성 복원을 위한 오염방지 시설을 시범 설치하였다. 지하수공에 대한 오염 정도를 조사한 결과 PS-1, CW-1, 그리고 CW-2 공이 질산성질소로 오염되어 먹는물 수질기준을 초과하였고, CW-3 공은 탁도가 먹는물 수질기준을 초과하였다. 오염원은 지하수공 개발시 수량 확보를 위하여 그라우팅을 제대로 하지 않은 불량시공으로 인한 오염된 지표수의 유입으로 기인되었다. 금번 연구는 오염된 지하수의 환경성 복원을 위한 것으로, 오염원과 지하수를 격리시켜 오염물질의 지하수 내 유입을 방지할 수 있도록 패커 그라우팅을 완벽하게 다시 실시하였으며, 오염방지시설을 설치하였다. 이 연구를 위하여 먼저 대수층의 분포 및 특성팍악, 지하수공내 지표수의 유입구간 규명, 지하수 오염원, 오염실태, 오염경로 등을 파악하였다 오염방지시설을 설치한 후, 설치 전,후의 질산성질소와 탁도의 함량을 비교하기 위하여 수질 분석을 실시하였다. PS-1의 경우, 오염방지시설 설치전의 질산성질소 함량은 16.1 mg/L 이었으나, 설치후에는 8.1 mg/L, 7.9 mg/L로써 설치전에 비하여 51% 감소되었으며, CW-1은 10.3 mg/L에서 6.3mg/L으로 39%, 그리고 CW-2는 14.9 mg/L에서 9.0 mg/L 으로 40% 감소되었다. CW-3 공의 탁도는 157 NTU에서 0.97 NTU로 완벽하게 복원되었다.

• Journal of Ginseng Research
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• v.2 no.1
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• pp.59-66
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• 1977

Mineral contents of sail in two-year-old ginseng plantation. of the top-dressings for ginseng and of the green grasses (Chung-Cho) were analyzed in order to clarify budget of inorganic nutrients of ginseng Plant. The amount of mineral nutrients contained in soil of two-year-old ginseng plantation had 56 times of nitrogen, 1.2 times of phosphorus and 20 times of potassium as compared with the requisition of two to sin-year-old ginseng plants per $\textrm{m}^2$. In consideration of the lack of phosphorus, it is recommendable to use bone mill as top dressing, which contains higher content of Phosphorus than ether top-dressings.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.136-136
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• 2010

$Ge_2Sb_2Te_5$ (GST)는 광학 스토리지 및 PRAM(Phase-change Random Access Memory)에 적용 가능한 대표적인 상변화 물질이며 상변화 거동에 대한 다양한 연구가 진행되고 있다. 차세대 비휘발성 메모리로 각광을 받고 있는 PRAM의 경우 저전력 그러나 향후 고집적, 고성능 PRAM 소자구현을 위해서는 Reset 전류 감소를 통한 소비 전력 감소, 인접 셀간의 'cross talking'을 방지할 수 있는 열적 안정성 개선 등의 문제점들을 해결해야 한다. GST 물질의 전기적, 열적 특성을 조절하여 이러한 문제를 해결하기 위하여 GST 물질에 이종의 원소를 첨가하는 연구가 활발히 진행되고 있으며, 특히 질소 첨가에 의해 결정 성장 억제를 통한 결정화 온도 증가, 결정질의 저항 증가 등의 보고가 있었다. 본 연구에서는 질소를 첨가한 N-doped $Ge_2Sb_2Te_5$ (NGST) 박막의 상변화 거동을 규명하고 GST 박막과 비교하여 첨가된 질소의 영향을 분석하고자 한다. D.C Magnetron sputtering 방법으로 증착된 GST와 NGST 박막을 등온으로 유지하여 각 온도별로 열처리 시간 증가에 따른 비저항을 실시간으로 측정하여 GST와 NGST 박막의 상분율을 계산하고 Kissinger 모델을 이용하여 effective activation energy ($E_a$)를 구하였다. GST와 NGST 박막의 $E_a$는 각각 $2.08\;{\pm}\;0.11\;eV$와 $2.66\;{\pm}\;0.12\;eV$로 계산되었다. 따라서 첨가된 질소에 의해 NGST 박막의 결정화를 위하여 GST 박막의 경우보다 더 큰 활성화 에너지가 필요하다.

• Plant Journal
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• v.15 no.2
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• pp.46-55
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• 2019

This paper presents a LNG Liquefaction cycle configuration using two stages of methane expansion (i.e. spliting into two stages as warm & cold to generate an additional inflection point within a cold composite curve) and a single stage of nitrogen expansion to improve the efficiency of the conventional Methane & Nitrogen Expansion Cycle. In comparison with Double Nitrogen Expansion Cycel and Methane & Nitrogen Expansion Cycle, the cycle efficiency has increased approximately from 13.92 and 13.13 to 12.08 kW/ton/day (8~15% efficiency increase). A Life Cycle Cost (LCC) analysis based on Net Present Value (NPV) also show an improvement in therms of project NPV, against a minor increment of a CAPEX.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.25-31
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• 2000

In order to investigate the composition, seasonal and regional variation of extractive nitrogenous components in the raw anchovy (Engraulis japonica) harvested from June 1991 to June 1992 at Nam-hae and Ki-jang in the southern coast of Korea, the contents of extractive nitrogen (EN), free amino acids (FAA), oligopeptides (OP), ATP and its related compounds (ARC), quaternary ammonium bases, and guanidino compounds were measured. The EN contents of raw anchovy were $444{\~}773\;mg/100\;g$. Thirty-four kinds of FAA were found and their total amount were $1,049{\~}2,079\;mg/100\;g$. Histidine, taurine, alanine, leucine and glutamic acid were the major free amino acids in the anchovy extracts. The amount of ARC was average $5.02\;{\mu}mol/g$, and IMP was the major compound among them, who and creatine contents in the extracts or raw anchovy were average 164 and 229 mg/100 g, respectively. The contents of glycinebetaine,${\brta}-alaninebetaine,\;{\gamma}-burobetaine$, homarine, TMA, and creatinine were extremely small. As for the regional and seasonal disparities, the Nam-hae samples contained more EN, FAA, OP, betaines and creatine than the Ki-jang samples. On the other hand the Ki-jang samples contained more ARC and TMAO. The spring samples contained more EN, FAA, OP, ARC and betaines than the autumn samples. On the other side the autumn samples contained more TAMO and creatine.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.353-359
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• 1996

Micro plot study was conducted to elucidate the behavior of nitrogen derived from animal manure in soil and to obtain the fundamental information on animal waste management. Soils used in this experiment were sandy loam and loam. Soil water samplers (1m length ceramic cup tube) were installed at 90cm depth of soil to collect the percolate. Fresh and fermented pig manure were applied at the rate of 0, 50, 100 ton per ha. Maize was grown to evaluate the effect of crop on nitrogen behavior through soil profile. Concentration of nitrate nitrogen in percolate increased by application of pig manure. This trend was more obvious at the loam with fermented pig manure than sandy loam with fresh pig manure treatment. The concentration of nitrate nitrogen was lower under the maize cultivation than bare soil condition by 64.6-68.9%. Concentration of Ca, Mg and Na of soil and percolate increased as nitrate nitrogen concentration increased. The equivalent ratio of cation to nitrate nitrogen of percolate was increased by application of pig manure. This result showed that canon leaching was accompanied by nitrate nitrogen. Concentration of nitrate nitrogen of subsurface soil was increased by pig manure application.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.217-222
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• 2011

Professional turfgrass applicators have reduced or eliminated phosphorus from their fertilization programs based on the assumption that soil phosphorus levels are supplying adequate amounts of phosphorus to the turfgrass. The previous researchers found that there were no P effects for turfgrass growth especially for mature turf. No effects may result from high P level in heavy thatch layer. The research was conducted for one year to investigate the effects of phosphorus fertilization programs on turfgrass performance, and monitor soil and plant tissue nutrient levels to determine the impact of the programs on a newly seeded Kentucky bluegrass. The nitrogen treatments were 20, 30 and $40g\;m^{-2}\;yr^{-1}$. The low, medium, and high nitrogen treatments were applied over 2, 4 and 6 applications, respectively. Nitrogen was applied using a formulation containing 30% of slow and 70% of fast release nitrogen sources that are representative of typical home lawn fertilizers. The phosphorus treatments were 0, 10 and $20g\;m^{-2}\;yr^{-1}$. Phosphorus was applied according to the application schedule for the nitrogen treatments. Kentucky bluegrass was seeded in May, 2010. The thickness of thatch layer was less than 1 cm and the first treatment was applied to Kentucky bluegrass in April, 2011. The low N rate treatment had acceptable color and quality ratings without high clipping yields. The high N rate treatment consistently had the highest color and quality ratings but also had very high clipping yields in comparison to the low and medium N rate treatments. Although there are significant differences in tissue P, Overall, there was no effect of phosphorus on color, quality, or clipping weights.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.1
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• pp.23-27
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• 1990

To elucidate the influence of nitrogen application rate on cool tolerance at the booting stage and respiratory activity of anther at the heading stage in the rice plants, the relationships among nitrogen content in the leaf blade and leaf sheath+culm at young microspore stage, cool tolerance at the booting stage and respiratory activity of anther at the heading stage were investigated for 3 rice cultivars-Yeomyungbyeo, Unbongbyeo and Milyang 23. Nitrogen content in the leaf blade at the young microspore stage was negatively correlated with respiratory rate of anther at the heading stage and fertility index, respectively. Respiratory activity of anther at the heading stage with 10ppm nitrogen application was higher than that of anther with 100ppm nitrogen application. On the Arrhenius plot of respiratory activity of anther at the heading stage, Yeomyungbyeo and Unbongbyeo showed a break at 18$^{\circ}C$ and 18.5$^{\circ}C$, respectively, with 100ppm nitrogen application, but did not show a break in respiratory activity of anther with 10ppm nitrogen application, while Milyang 23 showed a break at 20.5$^{\circ}C$ and 21$^{\circ}C$ with 10ppm and 100ppm nitrogen application, respectively. The highest correlation coefficient between fertility and respiratory rate of anther at the heading stage was shown at 20$^{\circ}C$ in the temperature range of 15$^{\circ}C$-30$^{\circ}C$.

• Journal of the Korean Applied Science and Technology
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• v.33 no.4
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• pp.795-801
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• 2016

This study is on the denitrification process using the sodium alginate and $CaCl_2$ as a flocculant. Removal techniques of nitrate nitrogen from waste water are reverse osmosis, ion exchange, electro dialysis and biological method etc. We tried to remove nitrate nitrogen with flocculation and sedimentation method in the present study. Calcium alginate is expected to form a chelate bond with nitrate nitrogen in the solution. So the effects of flocculantt component, flocculation reaction time, molar ratio of the flocculant, flocculant injection rate are studied to determine the best removal rate of nitrate nitrogen. In addition, we tried to determine the nitrate nitrogen removal mechanism by analyzing the structure and component ratio of the configuration after the agglutination precipitate by FE-SEM and EDS. As a result, the nitrate nitrogen removal mechanism is turned out to form calcium-nitro-alginate, and the best mole ratio of flocculating agent is 1 : 1, the injection rate of the flocculant was up to 2%, the removal rate of the nitrate nitrogen to be 56.7% in the synthetic wastewater.