• Korean Journal of Soil Science and Fertilizer
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• v.10 no.2
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• pp.85-92
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• 1977

The six soybean cultivars (Lee, Hill, Harosoy, Clark-63 Chippewa and R56-49) different in phosphorus sensitivity were cultured with $NH_4-N$, $NO_3-N$ or urea-N under water culture condition. Free sugars and organic chrematogram. Three peaks (unknown x, y and sucrose) were appeared as considerable main peaks. The X compound appeared as trace in the nitrate fed plant while unexpectedly high in ammonium or urea fed plant. The Y compound tend to decrase in urea fed plant. Sucrose was trace in ammonium fed plant but it was greater in urea onethan in nitrate one. The X was assumed a four carbon sugar acid derived from erythrose or a ring compound derived from purine or pyrimidine. While Y was assumed a hexose derived from glycolysis path. Since Y/x ratio is a good index of phosphorus sensitivity (inve rserelation) these compounds appears keycompounds to elucidate phosphorus sensitivity and ammonium toxicity.

• Korean Journal of Materials Research
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• v.16 no.11
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• pp.681-686
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• 2006

Plasma nitrocarburising and plasma post oxidation were performed to improve the wear and corrosion resistance of S45C and SCM440 steel by a plasma ion nitriding system. Plasma nitrocarburizing was conducted for 3h at $570^{\circ}C$ in the nitrogen, hydrogen and methane atmosphere to produce the ${\varepsilon}-Fe_{2-3}$(N, C) phase. Plasma post oxidation was performed on the nitrocarburized samples with various oxygen/hydrogen ratio at constant temperature of $500^{\circ}C$ for 1 hour. The very thin magnetite ($Fe_3O_4$) layer $1-2{\mu}m$ in thickness on top of the $15{\sim}25{\mu}m$ ${\varepsilon}-Fe_{2-3}$(N, C) compound layer was obtained by plasma post oxidation. A salt spray test and electrochemical testing revealed that in the tested 5% NaCl solution, the corrosion characteristics of the nitrocarburized compound layer could be further improved by the application of the superficial magnetite layer. Throttle valve shafts were treated under optimum plasma processing conditions. Accelerated life time test results, using throttle body assembled with shaft treated by plasma nitrocarburising and post oxidation, showed that plasma nitrocarburizing and plasma post oxidation processes could be a viable technology in the very near future which can replace $Cr^{6+}$ plating.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.405-411
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• 2012

This study was conducted to evaluate short-term effects on soil properties and leaf characteristics after various treatments of soil amendments (organic fertilizer: 20 kg tree-1; compound fertilizer+wood-char: compound fertilizer 4 kg tree-1+wood-char 2 kg tree-1; lime fertilizer: 3 kg tree-1; mixed fertilizer: compound fertilizer 1 kg tree-1+organic fertilizer 10 kg tree-1+wood-char 1 kg tree-1; control) in chestnut (Castanea crenata S. et Z.) orchards of Jinju and Sancheong, Gyeongsangnam-do. Soil bulk density, soil pH, soil organic carbon, total nitrogen, exchangeable Ca2+ and Mg2+ in chestnut orchards were not significantly affected by soil amendment treatments. However, leaf weight was significantly higher in the lime fertilizer ($0.65\;g\;leaf^{-1}$) in Jinju and the organic fertilizer ($0.68\;g\;leaf^{-1}$) in Sancheong than in the control treatments (Jinju: $0.46\;g\;leaf^{-1}$; Sancheong: $0.53\;g\;leaf^{-1}$). Leaf area was also significantly higher in the lime fertilizer ($79.1\;cm^2\;leaf^{-1}$) in Jinju and the soil amendments ($70.4\;cm^2\;leaf^{-1}{\sim}78.2\;cm^2\;leaf^{-1}$) in Sancheong than in the control treatments (Jinju: $56.2\;cm^2\;leaf^{-1}$; Sancheong: $60.5\;cm^2\;leaf^{-1}$). Nitrogen concentration of leaf increased significantly in the mixed fertilizer (2.51%) and the compound fertilizer+wood-char (2.50%) compared with the control (1.98%) treatments. The results suggest that soil properties were not affected by soil amendment treatments during short-term period, but leaf characteristics and nitrogen concentration can be an indicator of soil nutrient improvements in chestnut orchards.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.283-289
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• 1998

A bacterial strain KH-95 producing a high concentration of red pigment was isolated from the soil. The strain KH-95 was identified as a strain of Serratia sp. based on morphological and physiological characteristics. The optimal temperature and initial pH range for the production of pigment were 28$^{\circ}C$ and 7.0-8.0, respectively. The red pigment was purified through solvent extraction and silica gel column chromatography. Analyzing the structure of this pigment by instrumental analysis, it was identified as prodigiosin-like compound. In optimization of carbon and nitrogen sources, all carbon sources tested in this work inhibited the production of pigment except oils. Casein fumed out to be the most suitable nitrogen source for pigment production. Other nitrogen sources such as yeast extract, beef extract and peptone showed good cell growth but potently inhibited the production of pigment.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.396-400
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• 2002

This study was conducted to evaluate the dry matter (DM) yield, quality and utilization of nutrients in Korean lespedeza (Lespedeza stipulacea Maxim.) swards as a roughage source. DM yield in various stages, chemical composition, and DM digestibility were observed, and DM intake, digestibility and utilization of nitrogen and energy by Korean native goat were determined. Experimental diets include three treatments: mixture hay (MH) 100%, MH (80%)+wild Korean lespedeza hay (LH) 20% and MH (60%)+LH (40%). As growth stage advanced, the DM yield of Korean lespedeza tended to increase significantly (p<0.05). The mean DM yield of all growing stages was observed as 7,336 kg/ha. Crude protein (CP) content of Korean lespedeza tended to decrease, but fibrous contents tended to increase when the growth stage advanced. The tannin content of Korean lespedeza was the highest at the bud stage (64.7 mg/g). However, it showed a tendency to decrease as the growth stage advanced, and thus it was the lowest at the ripe seed stage (26.8 mg/g) (p<0.05). With increasing level of LH, voluntary DM intake by Korean native goats slightly increased, but no differences were observed between diets. The digestibility of DM, cellular constituents and NDF was slightly higher in LH containing diets than that of MH 100% diet (p<0.05). There was no significant difference in apparently digested N% among all diets, but retained N% and retained N% of the absorbed were higher in MH (60%)+LH (40%) than those of other diets (p<0.05). A difference in the utilization of energy was not detected. In conclusion, Juvenile LH improved the digestibility of nutrients, presumably due to its high CP content and low fibrous compound. Especially, tannin in LH did not affect in DM intake, but increased the nitrogen utilization of Korean native goats. Accordingly, it could be suggested that Korean lespedeza has a potential to be provided as a roughage source for Korean native goats.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.3
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• pp.134-139
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• 2004

A study was made on the synthesis of a carbonate base nitrogen-free deliming agent using a non-phosgene compound applicable to the deliming process, which is one of the biggest sources of pollutant increasing the T-N concentration in the effluent from the leather making processes. And also studied on the possibility of using the agent in the deliming process. Through measurement of T-N, BOD, COD and SS in the effluent after the agent is used, contents of Ca and Cr and TS in the leather after the deliming process were measured, by which deliming efficiency, influences to the physical properties of the chromium tanned leather and reducing effects of T-N, BOD, COD and SS concentrations in the effluent could be confirmed. Thus an eco-friendly study has been conducted.

• Mycobiology
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• v.39 no.2
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• pp.103-108
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• 2011

Amylases and cellulases are important enzymes that can be utilized for various biological activities. Ten different wild Nigerian mushrooms (Agaricus blazei, Agaricus sp., Corilopsis occidentalis, Coriolus versicolor, Termitomyces clypeatus, Termitomyces globulus, Pleurotus tuber-regium, Podoscypha bolleana, Pogonomyces hydnoides, and Nothopanus hygrophanus) were assayed for production of these secondary metabolites. The results revealed that most of the tested wild fungi demonstrated very good amylase and cellulase activities. With the incorporation of carboxymethyl-cellulose (a carbon source) into the culture medium, Agaricus blazei had the highest amylolytic activity of 0.60 unit/mL (at $25^{\circ}C$, pH 6.8). This was followed in order by P. tuber-regium and Agaricus sp. with 0.42 and 0.39 unit/mL, respectively ($p {\leq} 0.05$). Maltose and sucrose supplementation into the submerged liquid medium made N. hygrophanus and P. hydnoides to exhibit very low amylase activities of 0.09 and 0.11 unit/mL, respectively. Introducing peptone (an organic nitrogen source) into the basal medium enhanced the ability of C. versicolor to produce a cellulase value of 0.74 unit/mL. Other organic nitrogen sources that supported good cellulase activities were yeast extract and urea. Sodium nitrate (inorganic nitrogen source) generally inhibited cellulase production in all mushrooms. The best carbon source was carboxymethyl-cellulose, which promoted very high cellulase activity of 0.67 unit/mL in C. versicolor, which was followed in order by P. tuber-regium, T. chypeatus, and C. occidentalis ($p {\leq} 0.05$). Sucrose was the poorest carbon compound, supporting the lowest values of 0.01, 0.01, and 0.14 unit/mL in P. hydnoides, A. blazei, and Agaricus sp., respectively.

• Transactions of Materials Processing
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• v.28 no.1
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• pp.43-48
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• 2019

Aluminum nitride (AlN) is used by the semiconductor industry, and is a compound that is required when manufacturing high thermal conductivity. The AlN films with c-axis orientation and thermal conductivity characteristic were deposited by using the Pulsed Laser Deposition (PLD). The AlN thin films were characterized by changing the deposition conditions. In particular, we have researched the AlN thin film deposited under optimal conditions for growth atmosphere. The epitaxial AlN films were grown on sapphire ($c-Al_2O_3$) single crystals by PLD with AlN target. The AlN films were deposited at a fixed temperature of $650^{\circ}C$, while conditions of nitrogen ($N_2$) pressure were varied between 0.1 mTorr and 10 mTorr. The quality of the AlN films was found to depend strongly on the $N_2$ partial pressure that was exerted during deposition. The X-ray diffraction studies revealed that the integrated intensity of the AlN (002) peak increases as a function the corresponding Full width at half maximum (FWHM) values decreases with lowering of the nitrogen partial pressure. We found that highly c-axis orientated AlN films can be deposited at a substrate temperature of $650^{\circ}C$ and a base pressure of $2{\times}10^{-7}Torr$ in the $N_2$ partial pressure of 0.1 mTorr. Also, it is noted that as the $N_2$ partial pressure decreased, the thermal conductivity increased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.2
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• pp.157-166
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• 1995

The fate and use efficiency of applied nitrogen were evaluated in a pot experiment with different fertilizers and water management practices during 30days after fertilizer application. N-P-K compound fertilizers, 13-10-1l(F-l) for upland Crop use and 15-10-10(F-3) for rice Crop use, and mixed fertilizer, 21-17-17(F-2) for basal dressing in rice were used. Fertilizers corresponding to 1.8g N were mixed thoroughly with the whole volume of sandy loam soil in a pot. The pots were flooded upto 3cm above soil surface for O(0dF), 10(10dF), 20(20dF), and 30(30dF) days after fertilizer application and all the treatments were flooded continuously from 30 days after fertilizer application. During the flooding period water percolation rate was adjusted to 2.5mm/day. Rice seedlings were transplanted 40 days after fertilizer application. The pH of infiltrated water increased with increasing duration of flooding. The pH of F-2 was higher than those of F-1 and F-3 between which there were no differences. The applied nitrogen remained 23% in F-1, 29% in F-2, and 29.1 % in F-3, and 45.0% in 0dF, 26.6% in 10dF, 24.8% in 20dF, and 20.3% in 30dF as inorganic nitrogen at 63 days after fertilizer application. Nitrogen losses by leaching amounted to 51.3%, 32.1% and 48.1% of applied nitrogen in F-1, F-2 and F-3, respectively. Nitrogen leaching losses increased with increasing duration of flood- ing, amounting to 25.7%, 29.8%, 32.7%, and 35.8% in 0dF, 10dF, 20dF and 30dF, respectively. Gaseous loss of applied nitrogen was greatest in F-2, followed by F-1 and F-3. Total loss of nitrogen due to gaseous volatilization and leaching was greatest in F -1, followed by F -2 and F-3, and were greater in the treatments with longer flooding after fertilizer application. Nitrogen recovery by rice shoot until 72 days after transplanting were 23.2%, 24.7% and 27.4% of applied nitrogen in F-1, F-2 and F-3, respectively and 34.1%, 25.5%, 21.1%, and 21.2% in 0dF, 10dF, 20dF and 30dF, respectively.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.101-110
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• 2009

This study was conducted to investigate the effect of compound fertilizer contained slow release nitrogen such as isobutylidene diurea(IBDU) and methylene urea(MU) on kentucky bluegrasss and the change of nitrogen in the root zone after supplying these at AM turfgrass research institute with soil analysis, chlorophyll content index, leaf area index and dry weight during 6 months from July to December in 2007 year. Fertilizer treatments were designed as following; non-fertilizer(NF), straight fertilizer(CF), methylene urea(MU), isobutylidene diurea(IBDU). The every treatments were arranged a randomized complete block with three replications. Results obtained were summarized as follows: As relative to time after N fertilizers application, ammonium and nitrate in soil were increased, but T-N was decrease. The change of ratio of available Nand T-N by elapsed time after fertilizing was decreased in CF from 30days but increased until 45days. Compared with NF, the turf color index in CF, MU and IBDU was increased 1.5%, 2.5% and 2.3%, respectively, the chlorophyll content 16%, 25% and 26%, the dry weight 31%, 62% and 46% and shoot number 104%, 185% and 148%. The chlorophyll content index of MU and IBDU was increased 7.5% and 8.8% than that of CF, shoot number 40% and 22%, and dry weight 24% and 12% but turf color index was similar to that of CF. These results showed that the MU and IBDU application was supplied nitrogen for a long time in root zone by increasing an available nitrogen, and so promote turf grass growth such as chlorophyll content and shoot number in kentucky bluegrass.