• Title/Summary/Keyword: Nitrogen

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A Study on the Effects of N , $P_2O_5$ and $K_2O$ Application on the Vegetation and Dry Matter Yield in the Mixed Sward of Oechardrass and Crabgrass ( Digitaria sanguinalis [L.] Scop.) (Orchargrass와 바랭이 ( Digitaria sanguinalis [ L. ] Scop ) 혼생초지에 있어서 질소 , 인산 및 가리시용이 식생 및 건물수량에 미치는 영향)

  • 김창주
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.15 no.2
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    • pp.93-100
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    • 1995
  • This experiment was carried out to investigate how to effect the application of nitrogen, phosphate and potassium on the vegetation and dry matter yield in the mixed sward of orchardgrass and crabgrass (Digitaria sanguinalis [L.] Scop.). The experimental sward wa5 consisted of eight plots of non-application, P, K, PK, N. NK, NP and NPK. These plots were sown with seeds mixture of orchardgrass 17.5 kglha and crabgrass 17.5 kg/ ha on 22 April 1975 in the forage experimental field of Kangwon National University, Chunchon, Korea, and were cut four times from 6 July to 18 November 1975. The results obtained were summarized as follows: 1. In orchardgrass density measured after summering, the plot of nitrogen applied without phosphate marked only 3 1.0% of the plot of nitrogen applied with phosphate while in crabgrass density measured at that time the plot of nitrogen applied without phosphate marked as high as 112.5% of the plot of nitrogen applied with phosphate. 2. Application of phosphate and potassium improved wintering record of orchardgrass. In orchardgrass density measured after wintering, the plot of nitrogen applied without phosphate marked only 9.7% of the plot of nitrogen applied with phosphate, and the plot of NP applied without K marked 63.6% of the plot of NP applied with K. 3. In surface coverage of orchardgrass, in midsummer any plot applied with nitrogen regardless of accompanying with or not with phosphate wa5 0%, but in autumn the plot of nitrogen applied with phosphate was 56-58% and the plot of nitrogen applied without phosphate was 5%. While after wintering the plot of nitrogen applied with phosphate was 28-37% though the plot of nitrogen applied without phosphate was only 0.3-0.6%; the application of phosphate improved summering and wintering record of orchardgrass. 4. Application of phosphate demonstrated remarkable effect on increasing dry matter yield in orchardgrass. In year total yield of orchardgrass, the plot of nitrogen applied without phosphate marked as low as 11.3% of the plot of nitrogen applied with phosphate, but in crabgrass the plot of nitrogen applied without phosphate was almost equal to the plot of nitrogen applied with phosphate showing 97.5% of this plot. 5. Application of potassium was not effective on increasing dry matter yield of orchardgrass but its application was effective on increasing dry matter yield of crabgrass. In dry matter yield of orchardgrass significant difference was not found between NP plot and NPK plot, but in dry matter yield of crabgrass NPK plot recorded significantly higher yield compared with NP plot (p<0.05). 6. In botanical composition of the plot of nitrogen applied with phosphate, crabgrass recorded 46.5-50.5% in early summer (July) but in midsummer (August) it dominated the plot recording 85.6-91.2%. 7. In botanical composition based on the year total yield, in the plot of nitrogen applied with phosphate orchardgrass marked 21.7-26.2% and crabgrass recorded 73.8-78.370, but in the plot of nitrogen applied without phosphate orchardgrass marked only 3.5% being overwhelmingly dominated by crabgrass which recorded 96.5%. 8. Application of nitrogen not accompanied with phosphate strengthened competitive power of the crabgrass unilaterally, making orchardgrass be oppressed fatally by the crabgrass.

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The Response of Nitrogen Deposition to Methane Oxidation Availability and Microbial Enzyme Activities in Forest Soils

  • Jang, In-Young;Lee, Hyoung-Min;Kang, Ho-Jeong
    • Environmental Engineering Research
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    • v.15 no.3
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    • pp.157-161
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    • 2010
  • Forest soils are often nitrogen-limited, and nitrogen input to forest soils can cause substantial changes in the structure and functions of a soil ecosystem. To determine the effects of nitrogen input on methane oxidation and the microbial enzyme activities, manipulation experiments were conducted using nitrogen addition to soil samples from Mt. Jumbong. Our findings suggested that the addition of nitrogen to the soil system of Mt. Jumbong did not affect the microbial enzyme activities. Conversely, the addition of nitrogen affected the rate of methane oxidation. Inorganic nitrogen in soils can inhibit methane oxidation via several mechanisms, such as substrate competition, toxic effects, and competition with other microbes, but the inhibitory effects are not always the same. In this research, seasonal changes were found to produce different inhibitory factors, and these different responses may be caused from differences in the methantrophic bacteria community structure.

Effects of Cecectomy on Nitrogen Utilization and Nitrogen Excretion in Chickens Fed a Low Protein Diet Supplied with Urea

  • Son, J.H.;Karasawa, Y.;Nahm, K.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.3
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    • pp.274-276
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    • 1997
  • The effects of cecectomy on nitrogen utilization and nitrogen excretion were examined in single comb white leghorn (SCWL) cockerels fed a 5% protein diet supplied with urea. The cecectomy tended to increase nitrogen balance and nitrogen utilization and significantly decreased uric acid excretion (p < 0.01). Urea and ammonia excretion tended to be about 60% increased and decreased by cecectomy in SCWL cockerels, respectively, but blood ammonia, urea and uric acid concentrations were not affected. The results are in good agreement with those obtained previously in cecum-ligated chickens. It is concluded that the improvement of nitrogen utilization and decreases in urinary uric acid excretion in cecectomized chickens do not result from the modification of cecal fermentation.

Effects of Nitrogen on the Microstructure and Toughness of HAZ in Ti-Containing Steel (Ti 첨가강 열영향부 조직과 인성에 미치는 질소의 영향)

  • 김병철;방국수
    • Journal of Welding and Joining
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    • v.20 no.3
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    • pp.91-97
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    • 2002
  • Variation of HAZ toughness of Ti-containing steel with nitrogen content was investigated and interpreted in terms of its microstructure and the amount of soluble nitrogen present. The amounts of Ti and Al combined in TiN and AlN, respectively, in HAZ at $1400^{\circ}C$ peak temperature were less than those in base plate; 55~88% in TiN and 21~28% in AlN, indicating the dissolution of nitrifies in HAZ. The calculated amounts of soluble nitrogen using the thermodynamic analysis showed a good agreement with the measured values in other experiment. Therefore, the analysis can be used to estimate the amount of soluble nitrogen in HAZ. Simulated HAZ toughness was influenced not only by its microstructure but also by the amount of soluble nitrogen present after the formation of BN during the cooling cycle of welding. It showed maximum value when the nitrogen content is in stoichiometric ratio with titanium content, showing that soluble nitrogen in HAZ is detrimental to its toughness.

Development of cooling system with sub-cooled nitrogen for DC Reactor of 6.6 ㎸-200A class HTS fault current limiter (6.6 ㎸-200A급 HTS 한류기 DC Reactor용 과냉질소 냉각시스템의 개발)

  • 김형진;권기범;강형구;배덕권;안민철;정은수;장호명;고태국
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2003.10a
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    • pp.171-175
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    • 2003
  • The sub-cooled nitrogen cooling system at 65 K with GM cryo-cooler is developed for cooling down the DC reactor of 6.6 ㎸-200 A class HTS Fault Current Limiter(SFCL). The sub-cooled nitrogen cooling is more economic than saturated nitrogen cooling, because the length of HTS wire is reduced in the same capacity, as well as, more stable. The cooling system with the GM cryo-cooler installed on the cryostat is not only compact but also efficient for energy saving. In the nitrogen vessel, after evacuating with vacuum pump to saturated nitrogen at 65 K, sub-cooled nitrogen at 65 K is made by putting in gas helium to 1 atm. During the short circuit test occurring the fault current of 1000 A, the sub-cooled nitrogen cooled DC reactor for SFCL is kept the state of sub-cooled nitrogen at 65 K.

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The Energy Flow and Mineral Cycles in a Zoysia japonica and a Miscanthus sinensis Ecosystem on Mt. Kwanak 3. The Cycles of Nitrogen (관악산의 잔디와 억새 생태계에 있어서 에너지의 흐름과 무기물의 순환 3.질소의 순환)

  • 장남기;김정석;강경미
    • Asian Journal of Turfgrass Science
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    • v.9 no.4
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    • pp.265-273
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    • 1995
  • This investigation is carried out to clarify the cycles of nitrogen in the grassland ecosystems of Zoysia japonica and a Miscanthus sinensis on Mt. Kwanak. The hasic differential equation for the rate of change of nitrogen storage is illustrated hy huild-up and turnover of organic nitrogen, particularly in the ecosystems. The turnover velocity fractions of nitrogen for the Z. japonica and M .sinensis grasslands were k= 0. 181 and k=0. 166, respectively. The times required to reach 50, 95 and 99 percent of the steady state levels and turnover values of nitrogen on the grassland floors were 3.85, 16.67 and 27.78 years in the Z japonica grassland and 4.08, 17.65 and 29.41 years in the M sinensis grassland. The amount of annual cycles of nitrogen are 560.2 g /$m^2$ in the Z.japonica grassland and 654.1 g /$m^2$ in the M. sinensis grassland. Key words : Zsysia japonica Alisca nthus sinensis, Mt. Kivanak, Nitrogen cycle.

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Microstructure and Properties of High Nitrogen Sintered Stainless Steel

  • Pieczonka, Tadeusz;Stoytchev, Marin
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.568-569
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    • 2006
  • The use of the nickel free, high nitrogen stainless steel powder and nitriding during sintering of iron based materials have been shown as an alternative way to the conventional PM stainless steels containing nickel. Nitrogen as an alloying element for iron improves in an effective way the properties of sintered alloyed steels. The powder metallurgy route is a suitable way to introduce nitrogen into these alloys and, in particular, to produce high nitrogen (close to the solubility limit) stainless steels. The paper presents and discusses the nitriding behavior of nickel-free stainless steels produced by powder metallurgy method. Alloyed melt was atomized by nitrogen and in this way nitrogen was introduced into the powder. Further nitriding occurred during sintering in a nitrogen atmosphere. For comparison, compacts having the same composition as an alloyed powder were produced from elemental powders mixture. Sintering-nitriding behaviour of investigated materials has been controlled by dilatometry, chemical and X-Ray phase analysis and metallography. Mechanical properties of sintered compacts were also measured.

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Effect of Forms and Levels of Nitrogen Fertilizer on Plant Growth and Essential Oil Content of Agastache rugosa

  • Ohk, Hyun-Choong;Song, Ji-Sook;Chae, Young-Am
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.45 no.2
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    • pp.128-133
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    • 2000
  • This study was carried out to investigate the effect of forms and levels of nitrogen fertilizer on plant growth and essential oil production of Agastache rugosa. Calcium nitrate had more influenced on length and width of leaves and lateral branch length than did urea. When nitrogen fertilizer level was increased from 12 kgN/I0a to 24kgN/I0a, plant growth was stimulated and dry matter of leaf and inflorescence were increased. Top dry matter of plant with calcium nitrate treatment (38.4 g) was heavier than that of urea treatment (32.8 g). Interactions among accession and nitrogen form and nitrogen rate were not significantly different for top dry matter. The forms and rate of nitrogen fertilizer did not affect estragole content. The estragole contents was higher in leaf (91.8%) than that of inflorescence (81.3%). While the essential oil content was not affected by different nitrogen forms, nitrogen level affected the essential oil contents positively by increasing dry matter. Essential oil yield was not affected by accession or nitrogen form, but by nitrogen rate. With increasing N application from 12kgN/I0a to 24 kgN/I0a, essential oil yield was increased by 95.8 %.

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Yield and Free Sugar Contents of Burdock (Arctium lappa L.) depending on Nitrogen Levels

  • Lee, Ye-Jin;Sung, Jwa-Kyung;Lee, Seul-Bi;Lim, Jung-Eun;Song, Yo-Sung;Lee, Deog-Bae
    • Korean Journal of Soil Science and Fertilizer
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    • v.49 no.6
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    • pp.677-681
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    • 2016
  • Excessive nitrogen fertilization influences crop yields and quality as well as environmental pollution. In this study, yields, nitrogen use efficiency and free sugar contents of burdock (Arctium lappa L.) were evaluated at different levels of nitrogen fertilization. Nitrogen fertilizer was applied at 5 levels (0, 50, 100, 150, 200%) based on the conventional fertilization ($N=230kg\;ha^{-1}$), and phosphate and potassium fertilizer were treated by conventional P and K fertilization ($P_2O_5-K_2O=140-210kg\;ha^{-1}$) in all plots. The root yields of burdock were the highest in N 100~150% treatment plots. Nitrogen use efficiency and nitrogen recovery decreased from over N 150% treatment. Nitrogen uptake of root was greater than that of shoot in N 50~200% treatments. Fructose contents in root were inversely proportional to the level of nitrogen fertilization. As considering nitrogen recovery and root quality, economical burdock yield was obtained in N $230kg\;ha^{-1}$.

Characterization of a Nitrogen Fixing Bacteria Mycobacterium hominis sp. AKC-10 Isolated from the Wetland (습지에서 분리한 질소고정 세균인 Mycobacterium hominis sp. AKC-10의 특성)

  • Hong, Sun-Hwa;Shin, Ki-Chul;Lee, Eun-Young
    • Microbiology and Biotechnology Letters
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    • v.38 no.3
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    • pp.302-307
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    • 2010
  • Nitrogen is an element need to grow plants growth. Plants take up nitrogen in the form of nitrate or ammonium. Most of plants absorb nitrogen source as fertilizers. But from 50 to 70% of fertilizers applied were washed away. This study was conducted to isolate free-living nitrogen fixing bacteria from reed and to examine its beneficial traits for developing sustainable biofertilizers. Enriched consortium obtained from a reed in Ansan was developed for the fixing of nitrogen. Nitrogen fixing bacteria isolated from an enriched culture in Congo Red Medium was analyzed by 16s rDNA sequencing. AKC-10 was isolated and shown to have excellent nitrogen fixing ability. The optimum conditions of nitrogen fixing ability were $25^{\circ}C$ ($237.50{\pm}39.65\;nmole{\cdot}mg-protein^{-1}{\cdot}h^{-1}$ and pH 7 ($168.335{\pm}12.84$ nmole/hr mg-protein). It was identified as Microbacterium hominis [(AKC-10 (similarity : 99%)]. This strain was had to IAA (indole-3-acetic acid) productivity and ACC(1-aminocyclopropane-1-carboxylic acid) deaminase activity. Therefore, Microbacterium hominis AKC-10 stimulated plant development in the soil, enhancing the efficiency of remediation.