• Korean Journal of Soil Science and Fertilizer
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• v.34 no.6
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• pp.401-406
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• 2001

This study was conducted to find out the effect of slow-release nitrogen fertilizer, such as latex coated urea(LCU) and Meister10(MS10) on direct seeded rice in flooded soil(FS). Junghwabyeo, and early maturity rice cultivar grown on the plots which were treated with None-nitrogen, urea, LCU and MS10 plot. Growth characteristic, yield and yield components were investigated. Nitrogen uptake-efficiency and physico-chemical properties of soil before-after experiment were analyzed. Plant height and number of tillers $m^{-2}$ in LCU and MS10 plot at early grow stages were higher than those of Urea plot. MS10 and LCU plot showed similar tendency on the plant height but MS10 plot was higher than LCU plot on the number of tillers $m^{-2}$. The number of seedling $m^{-2}$ were no significant differences among None-N, urea, and MS10 plot. Heading date and leaf color were no significant differences among None-N, urea, and MS10 plot. Culm length in LCU and Ms10 plot were longer compared with urea plot, but panicle length were similar among with Urea, LCU and MS10 plot. Number of panicles $m^{-2}$ was highest in MS10 plot and it was similar between LCU and Urea plot. Yield were greater in order of Ms10 > LCU > Urea plot. Nitrogen uptake and nitrogen efficiency were greater in order of MS10 > LCU > urea plot. After the experiment, total content of nitrogen in soil was not changed at all treatments, but pH, P and K of soil were lower than that of before experiment at all treatments.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.2
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• pp.123-130
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• 2000

This study was carried out to examine the effects of animal manure on efficiency of the nitrogen utilization of silage corn (Zea mays L.) and soil fertility. The experiment was conducted on the field plot at Gongiam, Kwangju, Kyunggi-Do for 3 years, from 1996 to 1998, and arranged in split-plot design with three replications. The main plots were two kinds of composts such as swine manure fermented with sawdust (SMFWS) and swine manure fermented without sawdust (SMF). Subplots were the nitrogen fertilization rate (0, 100, 200, 300 and 400kgNhalyear). The nitrogen (N) yield increased as the nitrogen fertilization rate increased up to a rate of 300 kg Nha, but decreased at rate of 400 kg Nlha. Nitrogen yield in SMF treatments was higher than that of SMFWS treatments. But there were no significant differences between SMFWS and SMF treatments. Organic matter (OM) content of the soils in SMFWS was higher than that of SMF, &d was not significantly different between SMFWS and SMF treatments. OM content increased with increasing the nitrogen fertilization rate. Total nitrogen (TN) content of the soils increased as the nitrogen fertilization rate increased. No difference of TN content was found between SMFWS and SMF treatments. (Key words : Swine manure, Compost, Corn, Sawdust, Nutritive value)

• Korean journal of applied entomology
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• v.9 no.1
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• pp.15-20
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• 1970

An investigation was carried out to know the relationship between resistance of rice varieties to blast disease and the chemical components, especially total nitrogen and total sugars, in the rice plants. The results sic summarized as follow: 1) The nitrogen contents in the resistant variety were less than those of susceptible one, and sugar contents were reversed. Accordingly, the C/N ratio in the resistant variety was higher than that obtained by susceptible one. 2) The free amino acids contents, especially, Glutamine, Valine, Leusine and Iso-leusine, in the resistant varieties were more than those of the susceptible varieties. 3) The starch synthetic activity of rice leaves in the resistant varieties was higher than that of susceptible one in fructose and glucose solutions, but it was reversed in sucrose solution. 4) When more nitrogen was dressed, the total nitrogen content of rice leaves was increased than the ordinary dressing. The rate of increase in nitrogen content in resistant variety was lower than those of the susceptible. The total sugar content of rice plants dressed more nitrogen was decreased at early tillering stage, but increased at maximum tillering stage. It seemed that the rate of increase of total sugar in the resistant variety was higher than those of the susceptible.

• Corrosion Science and Technology
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• v.15 no.6
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• pp.281-289
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• 2016

The effect of nitrogen on the electrochemical corrosion and nanomechanical behaviors of martensitic stainless steel was examined using potentiodynamic polarization and nanoindentation test methods. The results indicate that partial replacement of carbon with nitrogen effectively improved the passivation and pitting corrosion resistance of conventional high-carbon and high- chromium martensitic steels. Post-test observation of the samples after a potentiodynamic test revealed a severe pitting attacks in conventional martensitic steel compared with nitrogen- containing martensitic stainless steel. This was shown to be due to (i) microstructural refinement results in retaining a high-chromium content in the matrix, and (ii) the presence of reversed austenite formed during the tempering process. Since nitrogen addition also resulted in the formation of a $Cr_2N$ phase as a process of secondary hardening, the hardness of the nitrogen- containing steel is slightly higher than the conventional martensitic stainless steel under tempered conditions, even though the carbon content is lowered. The added nitrogen also improved the wear resistance of the steel as the critical load (Lc2) is less, along with a lower scratch friction coefficient (SFC) when compared to conventional martensitic stainless steel such as AISI 440C.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.1
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• pp.75-81
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• 1997

This study was wnducte to investigate the effects of treatment level and seasons of sluny hm bovine feces on the productivity of rye, N efficiency and improvement of soil fertility under the Korean climate condition. The results obtained fiom this study summarized as follows ; 1. The highest dry matter yield of rye was obtained in the partial fertilization of sluny in spring or autumn. There is no differences of dry matter yield between spring and autumn application. 2. With increasing the amount of slurry-N, the dry matter yield of rye was signigicantly increased up to 100Kg sluny Nha. As the level of slurry-N rises above about 100Kg N/ha, the maximal yield of dry matter was unchanged or declined. 3. As the level of sluny fertilization rises, the crude protein content of rye increases significantly. However the contents of crude protein was less affected by the application seasons. 4. The amount of nitrogen which produced 6om rye is dependent upon the level of slurry-N. The highest nitrogen yield of rye was obtained by the partial fertilization of sluny-N. 5. The season or amount of slurry treatments did not affect the organic matter content in soil. N-content in soil was the lowest by the partial fertilization of slurry in spring or autumn. However, N-content was increased with the higher level of sluny-N.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.108-115
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• 2002

The effects of long-term fertilization on soil properties and nutrient availability are not well documented for cassava cultivation in Vietnam. In 1990, a field research plots were established with 12 treatments to test the effect of different rates of nitrogen (N), phosphorus (P) and potassium (K) on soil properties in Acrisols at Thai Nguyen University in Northern Vietnam. In 1999, composite soil samples (0 to 20cm depth) were collected from eight selected plots for measurements of nutrient supply rates by ion exchange membrane probes and for growing corn and canola in a growth chamber with and without added lime. Generally, long-term nitrogen (N) fertilization increased available N supply rates but decreased available potassium (K) and magnesium (Mg). Long-term phosphorus(P) applications increased canola N, calcium (Ca) and Mg uptake. Canola P uptake increased with increased P rates only when lime was added. Long-term K applications increased canola N, K, Ca, Mg uptake but only significantly increased corn N uptake. Liming significantly increased uptake of N, P, K, Ca, Mg and S for both corn and canola. However, N $H_{4-}$N, K and Mg soil supply rates were reduced when lime was added, due to competition between Ca from the added lime and other nutrients.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.4
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• pp.551-558
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• 2011

The aim of this study was to know whether leaf nitrate can be a substitute of total leaf N to justify plant N status and how nitrate influences macro elements uptake and physiological parameters of tomato plants under different nitrogen levels. Leaf nitrate content decreased in low N, while showed similar value with the control in high N, ranging from 55 to $70mg\;g^{-1}$. Differences in nitrate supply led to nitrate-dependent increases in macro elements, particularly cations, while gradual decrease in P. Physiological parameters, photosynthesis rates and antioxidants, greatly responded in N deficient conditions rather than high N, which didn't show any significant differences compared the control. Considering nitrogen forms and physiological parameters, total-N in tomato plants represented positive relation with growth (shoot dry weight), nitrate and $CO_2$ assimilation, whereas negative relation with lipid peroxidation.

• Analytical Science and Technology
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• v.18 no.5
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• pp.386-390
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• 2005

The zinc(II) complex, $Zn(NCS)_2(C_3H_4N_2S)_2$, I, has been synthesized and characterized by single crystal X-ray diffraction, thermal analysis and infrared spectroscopy. The complex I crystallizes in the triclinic system, $P\bar{1}$ space group with a = 7.587(1), b = 8.815(1), $c=12.432(2){\AA}$, ${\alpha}=75.584(8)$, ${\beta}=83.533(9)$, ${\gamma}=68.686(8)^{\circ}$, $V=750.0(2){\AA}^3$, Z = 2, $R_1=0.036$ and ${\omega}R_2=0.101$. The central Zn(II) atom has a tetrahedral coordination geometry, with the heterocyclic nitrogen atoms of 2-aminothiazole ligands and the nitrogen atoms of isothiocyanate ligands. The crystal structure is stabilized by one-dimensional networks of the intermolecular $N-H{\cdots}S$ hydrogen bonds between the amino group of 2-aminothiazole ligands and the sulfur atom of isothiocyanate ligands. Based on the results of thermal analysis, the thermal decomposition reaction of complex I was analyzed to have three distinctive stages such as the loss of 2-aminothiazole, the decomposition of isothiocyanate and the formation of metal oxide.

• Journal of the Korean institute of surface engineering
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• v.40 no.1
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• pp.39-43
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• 2007

The pure CrN powders oxidized to $Cr_2O_3$ noticeably above $850^{\circ}C$ in air. When these powders were sintered into bulk samples at $1500^{\circ}C$ under 40 atm of $N_2$ pressure, the CrN phase partly changed into the $Cr_2N$ phase, owing to the partial loss of nitrogen from CrN. When the bulk sample was heated at $1000-1200^{\circ}C$ for 100 hr under vacuum, the CrN phase also progressively changed into $Cr_2N$. At the same time, a relatively thin $Cr_2O_3$ layer formed on the bulk sample due to the reaction of chromium with residual oxygen in vacuum.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.1
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• pp.1-6
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• 1994

This experiment was carried out to study the effect of cutting frequencies(2, 3: one time grazed after 2 cuts, 3, 4, 6 cuts per year) and nitrogen fertilization(0 and 120 kg per ha and year) on botanical composition of permanent grassland at the "Federal Research Institute for Agriculture in Alpine Regions(Gumpenstein)," Austria The results are summarized as follows: 1. With only fertilizing phosphorus(P) and potassium(K),mean annual dry matter yields were 6.9 - 8.4 ton per ha and highest when only one time grazed after 2 cuts, but fell progressively with increase in cutting frequency and additonal fertilization of nitrogen. The average nitrogen efficiences expensed as dry matter yieldsfig) per feltilized nitrogenfig per ha) were 10.3 kg. 2. When N fertilizer was applied, the proportion of tall and medium grasses in the mixed swards increased by 30 - 50% compared with only fertilizing PK. Whereas swards with fertilizing only PK generally stimulated composition of the legumes at the expense of the grasses(30 - 50%). 3. Although the proportion of tall and medium grasses(Trisetum flavescens and Dachlis glomerara) and tall herbs(hntodon hispidus, Taraxacum oflcinale and Aegopodium podagraria) increased by infrequent cutting, frequently cutting plots helped increase the proportion of short grasses(Poa pratensis and Poa trivialis), especially where plots both had been applied with nitrogen fertilizer. 4. Nitrogen fertilization resulted in higher existence of herbs and weeds such as Taramcum oficinale. Aegopodium podagraria, Galium mllugo, Anthriscus silvestris and Lamium album. 5. Due to unusually high or low cutting frequencies such as 4 cuts or 2 cuts per year increased botanical compostion of Heracleum sphondylium.hondylium.