• Korean Journal of Environmental Agriculture
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• v.26 no.3
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• pp.223-227
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• 2007

This study was carried out to establish the reasonable level of nitrogen (N) fertilization based on soil nitrate nitrogen $(NO_3-N)$ content for cucumber (Cucumis sativus L.) under plastic film house. Cucumber plants were cultivated with standard and free N fertilization in eight soils which had various amount of $NO_3-N$ ranging from 67 to 343 mg/kg. The yield of cucumber was in the range of 1006 to 2369 g/plant depending on the nitrogen supplying capability of soils. The amount of $NO_3-N$ in the soil was negatively correlated with agronomic efficiency (AE) and N use efficiency (NUE). The critical level of soil $NO_3-N$ content for cucumber in N free fertilization was found to be about 260 mg/kg in Cate-Nelson analysis of variance between soil $NO_3-N$ and AE or NUE. Also the same critical soil $NO_3-N$ content was found in the yield and amount of N uptake of cucumber under N free fertilization. A standard N fertilization was required when soil $NO_3-N$ content was below 70 mg/kg. The optimal application rate of N fertilizer for cucumber in the soils containing $NO_3-N$ between 260-70 mg/kg could be recommended by the equation Y=-1.032X+269.2 (Y: N fertilization rate, kg/ha; X : soil $NO_3-N$ content mg/kg).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.5
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• pp.474-481
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• 2019

This study evaluated the chronic effects of $NO_3-N$ on juvenile blackhead seabream Acanthopagrus schlegelii. The experiment used six identically configured recirculating aquaculture systems (435 L), with three tanks (70 L) each. The $NO_3-N$ concentrations studied were 0 (control), 62.5, 125, 250, 500, and 1,000 mg/L $NO_3-N/L$. Thirty juvenile blackhead seabream ($18.8{\pm}2.2g$) were stocked in each tank. Growth and hematological changes were evaluated after 120 days. At the end of the experiment, the growth, survival, and cortisol levels indicated that blackhead seabream were healthy in 500 mg $NO_3-N/L$. However, insulin-like growth factor I (IGF-1) and the IGF-1 receptor were significantly lower at 250, 500, and 1,000 mg $NO_3-N/L$ than in controls (62.5 and 125 mg $NO_3-N/L$). Juveniles were likely affected at a much lower $NO_3-N$ concentration than 250 mg/L $NO_3-N/L$ in terms of IGF-1 and the IGF-1 receptor. Therefore, for the sake of long-term fish welfare, the $NO_3-N$ should be maintained at lower than 250 mg/L for blackhead seabream in recirculating aquaculture systems.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.151-152
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• 2003

대기중에는 토양입자나 해양입자와 같이 직접적으로 방출되는 입자상 물질 이외에 자연적으로 생성되거나 인간의 활동에 의하여 배출되는 유황, 질소산화물 및 유기물의 가스상 물질이 대기 화학 반응에 의하여 입자상 물질로 변환된 이차입자가 혼재되어 있다. 이러한 입자상물질은 $K^{＋}$, $Na^{＋}$, $Mg^{2+}$, NH$_4$$^{+}$, $Ca^{2+}$ 등의 양이온과 Cl$^{-}$, NO$_3$$^{-}$, SO$_4$$^{2-}$ 등의 음이온 성분으로 구성되어 있다. (중략)

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.307-308
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• 2000

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2149-2155
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• 2012

A metal-free and efficient procedure for the oxidation of alcohols into the corresponding carbonyl compounds has been described using ammonium nitrate in the presence of silica sulfuric acid under mild and heterogeneous conditions. The use of non-toxic and inexpensive materials, simple and clean work-up, short reaction times and good yields of the products are among the advantages of this method.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.6
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• pp.807-813
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• 2016

Two experiments were conducted assessing the effects of presence or absence of rumen protozoa and dietary nitrate addition on rumen fermentation characteristics and in vitro methane production in Brahman heifers. The first experiment assessed changes in rumen fermentation pattern and in vitro methane production post-refaunation and the second experiment investigated whether addition of nitrate to the incubation would give rise to methane mitigation additional to that contributed by defaunation. Ten Brahman heifers were progressively adapted to a diet containing 4.5% coconut oil distillate for 18 d and then all heifers were defaunated using sodium 1-(2-sulfonatooxyethoxy) dodecane (Empicol). After 15 d, the heifers were given a second dose of Empicol. Fifteen days after the second dosing, all heifers were allocated to defaunated or refaunated groups by stratified randomisation, and the experiment commenced (d 0). On d 0, an oral dose of rumen fluid collected from unrelated faunated cattle was used to inoculate 5 heifers and form a refaunated group so that the effects of re-establishment of protozoa on fermentation characteristics could be investigated. Samples of rumen fluid collected from each animal using oesophageal intubation before feeding on d 0, 7, 14, and 21 were incubated for in vitro methane production. On d 35, 2% nitrate (as $NaNO_3$) was included in in vitro incubations to test for additivity of nitrate and absence of protozoa effects on fermentation and methane production. It was concluded that increasing protozoal numbers were associated with increased methane production in refaunated heifers 7, 14, and 21 d after refaunation. Methane production rate was significantly higher from refaunated heifers than from defaunated heifers 35 d after refaunation. Concentration and proportions of major volatile fatty acids, however, were not affected by protozoal treatments. There is scope for further reducing methane output through combining defaunation and dietary nitrate as the addition of nitrate in the defaunated heifers resulted in 86% reduction in methane production in vitro.

• Journal of Hydrogen and New Energy
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• v.24 no.1
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• pp.29-35
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• 2013

A dense mixed ionic and electronic conducting ceramic membrane is one of the most promising materials because it can be used for separation of oxygen from the mixture gas. The $ABO_3$ perovskite structure shows high chemical stability at high temperatures under reduction and oxidation atmospheres. $BaCo_{1-x-y}Fe_xZr_yO_{3-{\delta}}$ (BCFZ) was well-known material as high mechanical strength, low thermal conductivity and stability in the high valence state. Glycine Nitrate Process (GNP) is rapid and effective method for powder synthesis using glycine as a fuel and show higher product crystallinity compared to solid state reaction and citrate-EDTA method. BCFZ was fabricated by modified glycine nitrate process. In order to control the burn-up reaction, $NH_4NO_3$ was used as extra nitrate. According to X-Ray Diffraction (XRD) results, BCFZ was single phase regardless of Zr dopants from y=0.1 to 0.3 on B sites. The green compacts were sintered at $1200^{\circ}C$ for 2 hours. Oxygen permeability, methane partial oxidation rate and hydrogen production ability of the membranes were characterized by using Micro Gas Chromatography (Micro GC) under various condition. The high oxygen permeation flux of BCFZ 1-451 was about $1ml{\cdot}cm^{-2}s^{-1}$. Using the humidified Argon gas, BCFZ 1-433 produced hydrogen about $1ml{\cdot}cm^{-2}s^{-1}$.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2158-2162
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• 2010

Studies on the molecular construction and structures of $M(NO_3)_2$ (M = Cu(II), Ni(II)) complexes with 1,2-bis(dimethyl-3-pyridylsilyl)ethane (L) have been carried out. Formation of each molecular skeleton appears to be primarily associated with a suitable combination of bidentate N-donors of L and coordinating nature of octahedral metal(II) ions: [$Cu(NO_3)_2(L)_2$] yields a 2-dimensional sheet structure consisting of 44-membered $Cu_4L_4$ skeleton whereas $[Ni(L)_2(H_2O)_2](NO_3)_2$ produces an interpenetrated 3-dimensional structure consisting of 66-membered cyclohexanoid ($M_6L_6$) skeleton. The Cu(II) ion prefers nitrate whereas the Ni(II) ion prefers water molecules as the fifth and the sixth ligands.

• Carbon letters
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• v.5 no.4
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• pp.180-185
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• 2004

Thermolysis of $Cu(NO_3)_2{\cdot}3H_2O$ impregnated activated carbon fiber (ACF) was studied by means of XRD analysis to obtain Cu-impregnated ACF. $Cu(NO_3)_2{\cdot}3H_2O$ was converted into $Cu_2O$ around $230^{\circ}C$. The $Cu_2O$ was reduced to Cu at $400^{\circ}C$, resulting in ACF-C(Cu). Some Cu particles have a tendency to aggregate through the heat treatment, resulting in the ununiform distribution in ACF. Catalytic decomposition of NO gas has been performed by Cu-impregnated ACF in a column reactor at $400^{\circ}C$. Initial NO concentration was 1300 ppm diluted in helium gas. NO gas was effectively decomposed by 5~10 wt% Cu-impregnated ACF at $400^{\circ}C$. The concentration of NO was maintained less than 200 ppm for 6 hours in this system. The ACF-C(Cu) deoxidized NO to $N_2$ and was reduced to ACF-$C(Cu_2O)$ in the initial stage. The ACF-$C(Cu_2O)$ also deoxidized NO to $N_2$ and reduced to ACF-C(CuO). This ACF-C(CuO) was converted again into ACF-C(Cu) by heating. There was no consumption of ACF in mass during thermolysis and catalytic decomposition of NO to $N_2$ by copper. The catalytic decomposition was accelerated with increase of the reaction temperature.

• Journal of Applied Biological Chemistry
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• v.44 no.3
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• pp.135-139
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• 2001

To observe the changes in isotopic composition (${\delta}^{15}N$) of $NO_3{^-}$ during denitrification, an incubation experiment using soil treated with nitrification inhibitor (2-chloro-6-trichloromethyl-pyridine) under water-saturated condition was conducted for 153 h. The $NO_3-N$ concentration decreased from 73.3 to $20.6mg\;kg^{-1}$ during the incubation period, with denitrification rate constant of $0.00905h^{-1}$, and ${\delta}^{15}N$ values of $NO_3-N$ increased from +0.9 to +25.5‰ with decreasing the $NO_3-N$ concentration. The increase in the ${\delta}^{15}N$ values of $NO_3-N$ is due to kinetic isotope fractionation, which always results in $^{15}N$ enrichment of the substrate. The isotopic fractionation factor calculated in this study was 1.0196, an indication that 1.96% more $^{14}NO_3{^-}$ reacted at a given time interval than a comparable number of $^{15}NO_3{^-}$. The ${\delta}^{15}N$ values measured through the incubation study showed a good agreement with the results calculated from the Fochts isotope fractionation model. Our results suggest that when the ${\delta}^{15}N$ of $NO_3{^-}$ is used for tracing the fate of N, the kinetic isotope fractionation associated with denitrification must be taken into consideration.