• 한국토양비료학회지
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• 제42권4호
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• pp.301-306
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• 2009

이 연구의 목적은 건강한 작물과 시들은 식물의 질소대사와 아스코리빈산 함량의 차이를 비교하는것에 있다. 시듬은 인공적으로 유도되었으며, 그방은 질소과다 시비 및 저칼륨 시비에 의한 것으로4개의 처리구를 두었다. 1N-1P-1K (control), 6N-1P-0K (0K), 6N-1P-0.5K (0.5K), and 6N-1P-2K (2K). 시듬 정도는 control, 0%; 2K, 10%; 0.5K, 40%; and 0K, 70%. 식물 생장에는 고질소 저 칼륨 처리구에서는 그리 큰 차이가 없었으며 질산태질소의 함량은 control 구와 비교하여 고 질소 처리구가 높았으며, 아스코리빈 산 함량은 고질소 처리구가 control구에 비하여 낮았음을 확인 할수 있었다.

• 한국토양비료학회지
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• 제8권2호
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• pp.105-111
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• 1975

질소(窒素)의 정조생산효율(正租生産効率)(E)과 수량(收量)(Y) 수확지수(收穫指數)(HI) 질소전이율(窒素轉移率)(T) 질소흡수량(窒素吸收量)(N) 정조중(正租中)N농도(濃度)(GN%) 고중농도(藁中濃度)(SN%) 전건물생산량(全乾物生産量)(TY) 간(間)의 관계(關係)를 4개질소영양환경(個窒素營養環境)(고위지(高位地)와 저위지(低位地)에서 6 및 12kg 시비수준(施肥水準))에서 수도품종(水稻品種)(구(舊) 및 신품종(新品種)) 간(間)에 단순상관분석(單純相關分析)으로 조사(調査)하였다. 질소(窒素)의 전건물(全乾物) 생산효율(生産効率) (TE)을 포함 이상(以上)의 두 인자(因子)들간(間)의 관계(關係)를 분석(分析)하였다. 1. E는 T, Y, HI와 유의정상관(有意正相關), SN%, N 및 GN와는 행의상관(行意相關)을, TY와는 부상관(負相關) 경향(傾向)을 보였다. 2. T는 GN% 및 Y와 유의정상과나(有意正相關)을, SN%와는 유의부상관(有意負相關)을 보였다. 3. TE는 TY와 유의정상관(有意正相關)을 N와는 유의부상관(有意負相關)을 보였다. 4. 품종간(品種間) E의 순위(順位)는 서로 다른 질소영양(窒素營養) 환경(環境)에서 일정성(一定性)을 보였다. 5. 이상(以上)의 결과(結果)들로 다수품종(多收品種)은 고전이율(高轉移率)에 기인(基因)한 고질소효율(高窒素効率)을 갖고 띠라서 고중(藁中) N농도(濃度)가 낮으며 자실(子實)로 전류(轉流)된 N는 광합성산물(光合成産物)에 의(依)하여 크게 희석(稀析)되는 것으로 결론(結論)된다. 6. 최근육종(最近育種)된 이수성(多收性) IR 계통(系統)의 기보(旣報)된 생리적(生理的) 특성(特性)은 이 계통(系統)의 고질소효율(高窒素効率)과 잘 일치(一致)하였으며 수도육종(水稻育種)은 질소효율(窒素効率)에 기반(基盤)한 선발(選拔)로 진행(進行)되어왔다. 7. 고질소효율(高窒素効率) 품종(品種)은 생육후기(生育後期)에 효율(効率)이 큰 토양질소(土壤窒素)를 흡수(吸收)할 수 있도록 생육초기(生育初期)에 근생장(根生長)에 질소효율(窒素効率)이 클 것으로 추정(推定)된다.

• Journal of Crop Science and Biotechnology
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• 제10권2호
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• pp.57-63
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• 2007

Due to the strong influence of nitrogen(N) on plant productivity, a vast amount of N fertilizers is used to maximize crop yield. Over-use of N fertilizers leads to severe pollution of the environment, especially the aquatic ecosystem, as well as reducing farmer's income. Growing of N-efficient cultivars is an important prerequisite for integrated nutrient management strategies in both low- and high-input agriculture. Taking maize as a sample crop, this paper reviews the response of plants to low N stress, the physiological processes which may control N-use efficiency in low-N input conditions, and the genetic and molecular biological aspects of N-use efficiency. Since the harvest index(HI) of modern cultivars is quite high, further improvement of these cultivars to adapt to low N soils should aim to increase their capacity to accumulate N at low N levels. To achieve this goal, establishment and maintenance of a large root system during the growth period may be essential. To reduce the cost of N and carbon for root growth, a strong response of lateral root growth to nitrate-rich patches may be desired. Furthermore, a large proportion of N accumulated in roots at early growth stages should be remobilized for grain growth in the late filling stage to increase N-utilization efficiency. Some QTLs and genes related to maize yield as well as root traits have been identified. However, their significance in improving maize NUE at low N inputs in the field need to be elucidated.

• Animal Bioscience
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• 제34권10호
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• pp.1600-1606
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• 2021

Objective: This study was conducted to enhance our understanding of nitrogen (N) metabolism and mammary amino acid (AA) utilization in lactating cows with divergent phenotypes of residual feed intake (RFI). Methods: Fifty-three multiparous mid-lactation Holstein dairy cows were selected for RFI measurements over a 50-d experimental period. The 26 cows with the most extreme RFI values were classified into the high RFI (n = 13) and low RFI (n = 13) groups, respectively, for analysis of N metabolism and AA utilization. Results: Compared with the high RFI cows, the low RFI animals had lower dry matter intake (p<0.01) with no difference observed in milk yield between the two groups (p>0.10). However, higher ratios of milk yield to dry matter intake (p<0.01) were found in the low RFI cows than in the high RFI cows. The low RFI cows had significant greater ratios of milk protein to metabolizable protein (p = 0.02) and milk protein to crude protein intake than the high RFI cows (p = 0.01). The arterial concentration and mammary uptake of essential AA (p<0.10), branched-chain AA (p<0.10), and total AA (p<0.10) tended to be lower in the low RFI cows. Additionally, the low RFI cows tended to have a lower ratio of AA uptake to milk output for essential AA (p = 0.08), branched-chain AA (p = 0.07) and total AA (p = 0.09) than the high RFI cows. Conclusion: In summary, both utilization of metabolizable protein for milk protein and mammary AA utilization are more efficient in cows with lower RFI than in the high RFI cows. Our results provide new insight into the protein metabolic processes (related to N and AA) involved in feed efficiency.

• 한국가금학회지
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• 제42권1호
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• pp.87-100
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• 2015

It is well known that dietary protein affects the growth performance and carcass composition of poultry. Over the last several decades, numerous studies have been carried out to investigate to optimize the level of dietary protein since the protein is an important and expensive constituent in poultry feed. It is generally accepted that dietary protein should represent a balance of amino acids supporting the requirements for growth and maintenance of birds. A protein with balanced essential amino acids that matches a bird's requirement and sufficient non-essential amino acid nitrogen to enable the synthesis of all of the non-essential amino acids, is referred to as an 'ideal protein'. Feeding of excess protein or amino acids may result in an amount of nitrogen emission. Most common method to reduce nitrogen emission is using diet formulation which has lower dietary crude protein level and higher concentration of amino acid supplements. However, there are conflicting reports whether low protein diets supplemented with synthetic amino acids can obtain the growth performance equal to high protein diets. Excessive nitrogen excretion caused by amino acid imbalance also may influence the environment of poultry house due to ammonia production from uric acid. These environmental conditions may increase the incidence of skin problem or respiratory diseases of chickens. Various strategies based on comprehensive understanding should be tested to optimize nitrogen utilization and reduce nitrogen emission while maintaining the performance in poultry production.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.351-355
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• 2003

Screening 실험을 통하여 결정된 주요인자인 sucrose, nitrogen, 배양온도로 인자의 최적수준을 결정하는 표면반응법중 하나인 Box-Behnken design을 수행하였다. 각 인자의 상관관계를 통하여 sucrose는 90 g/L, nitrogen은 41 mM, 온도는 $22^{\circ}C$가 최적수준으로 결정이 되었으며 확인실험을 통하여 대조구보다 세포생장이 증가하였을 뿐만 아니라 hGM-CSF의 생산도 약 2배 정도 증가되었음을 확인하였다. 이것은 고농도의 sucrose로 인해 배지내로의 hGM-CSF의 분비가 촉진되었기 때문이며 또한 저온으로 인해 분비된 hGM-CSF를 분해하는 protease 활성이 감소되었기 때문인 것으로 사료된다.

• 열처리공학회지
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• 제13권5호
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• pp.337-345
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• 2000

As a case hardening process for stainless steels, nitriding is more preferred and widely used than carburizing which deterioates corrosion resistance severely. In order to add the nitrogen into the stainless steels, passive film on the surface must be removed effectively before nitriding. Conventional gas nitriding process is performed in the temperature range of 500 to $600^{\circ}C$ with $NH_3$ gas, which often leads to sensitization of stainless steels. In this study, we tried to activate passive film of austenitic stainless steels by heating at low pressure. ($900^{\circ}C$, $5{\times}10^{-2}$ Torr.) Nitriding was performed at the solution treatment temperature of $1100^{\circ}C$ with nitrogen molecules instead of $NH_3$ gas. An attainable nitrogen content in a case depends on the nitrogen gas pressure at constant nitriding temperature. A case depth is proportional to the square root of solution time, which suggests that inward diffusion of nitrogen follows the Fick's 2nd law. Surface nitrogen atoms are dissolved as interstitial solutes, or precipitated in the form of MN, $M_2N$ nitrides, which increase the case hardeness. Dissolved nitrogen in the case enhances the cavitation resistance of austenitic stainless steels dramatically.

• 한국작물학회지
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• 제44권2호
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• pp.97-101
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• 1999

No-till direct seeding cultivation of rice has major advantages such as saving of labor and cost by eliminating tillage, preparation of seed bed and trans-planting procedure compared to the conventional transplanting cultivation. A field experiment was conducted to evaluate the effects of straw treatment and nitrogen levels on the rice growth in no-till direct-seeding cultivation. Rice straw, vetch straw, and the mixture of both of the straws were mulched on the surface of soil before seeding while 4 levels of nitrogen fertilizer, 0, 7, 9, and 11 kkg/10a respectively, were applied at 3 split times, 3-weeks after sowing, 5-weeks after sowing and the panicle initiation stage. Mulching of vetch straw significantly reduced seedling establishment of rice which may be attributed to low oxidation-reduction potential of soil by vetch mulching treatment. Vetch straw increased the concentration of soil ammonium leading to an extension of the greenish leaf to panicle initiation stage. Agronomic nitrogen use efficiency (AD $E_{N}$) in heavy-mixed straw mulching plots was lower than other treatments. Grain yield and AU $E_{N}$ in the vetch treatment were less affected by fertilized N levels. Conclusively, it is suggested that heavy straw mulching was not efficient for rice seedling establishment and nitrogen usage.e.

• 미생물과산업
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• 제26권1호
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• pp.18-30
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• 2000

질소 고정능이 있는 Nostoc pruniforme를 재료로, 3종의 유기물, glucose, oxalic, 및 ethanol을 N-free medium과 NO$^{[-993]}$ riched medium에 처리해 주었을 때 다음과 같은 효과를 얻었다. 1)N-free medium과 NO$^{[-993]}$ riched medium에서 위의 유기물 모두가 질소 고정과정의 energy원으로서 또는 substrate로서의 유효한 결과를 얻었다. 3)oxalic acid를 처리한 실험에서는NO$^{[-993]}$ richedmedium의 경우 고농도 처리구에서 질소고정량이 많았고 N-free medium은 그 반대의 결과였다. 4)비교구인 control의 질소 고정량은 일예를 제회하고는 전반적으로 고농도 처리구와 저농도 처리구의 중간에 위치했다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.106-106
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• 2022

An appropriate amount of nitrogen fertilizer input during rice cultivation is essential for rice growth, quality control, and reduction of greenhouse gases in paddy fields. Therefore, it is necessary to develop a technology that can check whether an appropriate amount of fertilizer is applied in paddy fields. In this study, we tried to derive a method for diagnosing nitrogen fertilization level using spectroscopic diagnosis, physiological analysis, and molecular indicator genes. Nitrogen fertilization treatment was performed in a greenhouse by dividing into five treatment conditions: no fertilization (N0), low fertilization (N0.5), standard fertilization (N1.0), excessive fertilization (N1.5), and double fertilization (N2.0), respectively. Growth characteristics analysis was investigated by nitrogen fertilization conditions and growth stages, and the height of the canopy was analyzed using a laser scanner. Physiological and spectroscopic analyses were performed by analyzing chlorophyll and sugar contents and measuring SPAD and leaf spectrometer on rice leaves. In addition, real-time PCR experiment was performed to check the relative expression levels of several known nitrogen metabolism related genes. These results suggest that spectroscopic techniques can be helpful in diagnosing the level of nitrogen fertilization in rice paddy fields.