• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.381-389
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• 2013

In order to study the effect of organic fertilizer on dry matter (DM) yield, nitrogen fixation and transfer from pea to barley, an experiment was carried out from May to June in 2008 in Incheon. A completely randomized block design with three replications was used for the experiment and one reference plot assigned each treatment for nitrogen fixation evaluation. Seeding mixture was 40kg barley and 80kg pea per ha. N rate of 40, 80 and 120kg/ha as organic fertilizer was applied at seeding. The equivalent of 1kg per ha as $(15NH_4)_2SO_4$ Solution at 99.8 atom N was applied to the plots ($30{\times}20cm$) at mid April. Forage was harvested from each plot in ripening stage at ground level and separated into barley and pea. Nitrogen fixation was 32.4%, 23.4% and 0% at three different organic N levels. Transfer rate were from 47.6% to 21.8% in difference method and 24.6% and 21.4% on $^{15}N$ dilution method. N Transfer amount were from 92.8kg/ha to 41.9kg/ha on difference method and 47.3kg in the 40kg N plots and 49.7kg in the 80kg N plots on $^{15}N$ dilution method but there was no N transfer in 120kg N organic fertilizer plots. Benefit from increased organic fertilizer was not clear in terms of nitrogen fixation and transfer from pea to barley in barley and pea mixtures.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.73-78
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• 2000

This study was conducted for 2 years at Chinju region to establish suitable seeding rate and fertilizing levels of nitrogen, phosphorous and potassium in spring-sown Jinyangbori. Heading and maturing were delayed by increasing fertilizers, especially nitrogen. Number of spikes per were secured by much seeding and increased application of nitrogen. One thousand grain weight reduced with increasing fertilization at any seeding rate. Relatively high harvest indices were observed with 12-10-4 at 10kg. 10a$^{-l}$ seeds planted, followed by 6-10-8 at 15 kgㆍ 10a$^{-1}$, and 6-10-4kgㆍ 10a$^{-l}$ at 20kg ㆍ 10a$^{-l}$ of N-P-K fertilizing combinations, respectively. There was no distinct differences on yield for various seeding rates in spring-sown barley. When seeding rate increased up to 15kgㆍ10a$^{-1}$, the positive effect of fertilizers was recognized as the function of balanced-application. It was possible to recommend 10kgㆍ10a$^{-1}$ as seeding rate and 6-5-4(N-P-K)kgㆍ10a$^{-1}$ as fertilizing combination in spring-time seeding considering low input and sustainable agriculture. There was no significant difference of protein content in grain by seeding rate. Increase of nitrogen fertilizer enhanced protein content in grain.

• Korean Journal of Materials Research
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• v.15 no.8
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• pp.514-517
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• 2005

Effects of nitrogen and oxygen annealing on the carrier concentration, carrier mobility, electrical resistivity and PL characteristics as well as the crystallinity of ZnO films deposited on sapphire substrates by atomic layer deposition (ALD). X-ray diffraction (XRD), Scanning electron microscope (SEM), photoluminescence (PL) analyses, and Hall measurement were performed to investigate the crystallinity, optical properties and electrical properties of the ZnO thin films, respectively. According to the XRD analysis results the crystallinity of the ZnO film annealed in an oxygen atmosphere is better than that of the ZnO film annealed in a nitrogen atmosphere. Annealing undoped ZnO films grown by ALD at a high temperature above $600^{\circ}C$ improves the crystallinity and enhances W emission but deteriorates the electrical conductivity of the flms. The resistivity of the ZnO film annealed particularly at $800^[\circ}C$ in a nitrogen atmosphere is much higher than that annealed at the same temperature in an oxygen atmosphere.

• Korean Journal of Weed Science
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• v.7 no.2
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• pp.171-178
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• 1987

This study was conducted to examine the possibility of complete lodging. prevention, the growth and yield of the paddy rice plant by paciobutrazol 0.6%G application at 15 days before heading under the several levels (0, 5, 10, 15, 20, 25, 30, 35, 40, 45 kg/10a) of nitrogen fertilizer in 1986. Culm length was shortened 10-15% by paclobutrazol application. The shortened rate of internode was very extreme on the 3rd and 4th internode in paclobutrazol application. Moment the height of center gravity and lodging index turned higher with increasing nitrogen fertilizer, on the other hand, those of paclobutrazol application were smaller than control. Lodging degree (0~4) was 1~3 above 25kg/10a level of nitrogen fertilizer in control, however, no more than 1 at 45kg/10a level of nitrogen fertilizer in paclobutrazol application. Ripened grain ratio and grain weight of paclobutrazol application were larger than those of control. Yield increased more 15-26% in paclobutrazol application than control. The nitrogen level of maximum yield was about 25kg/10a in control, but was 31kg/10a in paclobutrazol application.

• Journal of Mushroom
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• v.3 no.2
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• pp.75-78
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• 2005

The results of studies for determining the nutrients sources of mycelial growth for optimal condition of Pleurotus cornucopiae are as follows; 1) Optimal carbon source of mycelial growth of Pleurotus cornucopiae is maltose(357mg/25ml/15d); 2) Optimal nitrogen source of mycelial growth of Pleurotus cornucopiae is peptone(347mg/25ml/15d); 3) Optimal organic acid source of mycelial growth of Pleurotus cornucopiae is glutamic acid(389mg/25ml/15d); 4) Optimal vitamin source of mycelial growth of Pleurotus cornucopiae is biotin(399mg/15d); and 5) Optimal C/N ratio for mycelial growth for determining the condition of Pleurotus cornucopiae is 40(398mg/15d).

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.548-549
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• 1989

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.249-252
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• 2001

The green algae, Botryococcus braunii, has an unusually high hydrocarbon content, ranging from 15 to 75% of dry weight, as a long-chain unsaturated hydrocarbon. It has a potential as a renewable source of chemical feedstocks or fuels. The commercial production of hydrocarbon by B. braunii has not been achieved mainly due to their economic and several technical barriers. The B. braunii cultivation with piggery wastewater could alleviate to economic problems by the reduction of inorganic nutrients, mainly nitrogen and phosphorus from wastewater. We have been studying cultivation of B. braunii in the pretreated piggery wastewater by a MBR(membrane bioreactod, containing about 3000 mg $NO^3$ /L, 15 mg $NH_4\;^+/L$, 3 mg P/L, and others. The purpose of this study was to develop a continuous culture system in piggery wastewater and nitrogen-limited chemostat.

• Transactions of Materials Processing
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• v.15 no.2 s.83
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• pp.112-117
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• 2006

Sliding wear mechanism of a high nitrogen austenitic 18Cr-18Mn-2Mo-0.9N steel has been investigated. Dry sliding wear tests of the steel were carried out at various loads of IN-10N under a constant sliding speed condition of 0.15m/s against AISI 52100 bearing steel balls. Solution ($1050^{\circ}C$) and isothermal aging ($900^{\circ}C$) heat treatments were performed on the steel and the effect of the heat treatments on the wear was investigated. Wear rates of the solution-treated steel specimen remained low until 5N load, and then increased abruptly at loads above 5N. The rates of isothermally aged specimens were low and increased gradually with the applied load. Worn surfaces, their cross sections, and wear debris of the steel specimens were examined with a scanning electron microscopy. Phases of the heat-treated specimen and the wear debris were identified using XRD. The transformed phase underneath a sliding track was investigated and analyzed using a TEM. Effects of the phase transformation during the wear and $Cr_{2}N$ precipitates formed during the isothermal aging on the wear of the austenitic steel were discussed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.6
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• pp.918-924
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• 2020

This study investigated diurnal fasting and postprandial total ammonia nitrogen (TAN) excretion rates in juvenile Oplegnathus fasciatus (rock bream; mean body weight 45.8±1.1 g) at three temperatures (15, 20, and 25℃) in a recirculating system (three replicates). The fish were hand-fed twice daily (09:00 and 17:00 h) with commercial food (46.7% protein) until satiation. The results showed that the fasting and postprandial TAN excretion rates were temperature-dependent. The mean hourly rates were 7.7 (15℃), 10.2 (20℃), and 11.9 (25℃) mg kg fish-1 h-1 for fasting and 34.0 (15℃), 47.8 (20℃), and 60.2 (25℃) mg kg fish-1 h-1 for postprandial. At each temperature, two postprandial TAN excretion peaks were observed 2-4 h after feeding; the second peak was always higher. The TAN loss to nitrogen consumption ratio was 41.1-46.8 % and increased significantly with increasing temperature. Temperature affected fasting and postprandial TAN excretion in juvenile rock bream, providing insight for culture management.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.6
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• pp.697-701
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• 1998

In order to improve silage quality and utilization of napier grass (Pennisetum purpureum Schum.) by goats, the grass was ensiled with molasses (MOL) and/or defatted rice bran (DRB). Napier grass was harvested at the growing stage in July and cut into 3 cm length. The grass was mixed with 4% MOL and/or 15% DRB, ensiled 15 kg each into plastic bags and stored for 9 months. Dry matter content of the silage ensiled with MOL (MOL-silage) was 13.4%, but increased to 20% with DRB addition. The addition of MOL decreased pH value and ammonia nitrogen content, but increased lactic acid content. MOL-silage contained about 6% spoilage, but addition of DRB decreased spoilage to less than 1%. Goats were fed the silage at a level of 2.25% (DM basis) of their body weight. Goats fed DRB- or MOL/DRB-silages maintained nitrogen retention, but goats fed MOL-silage did not. The rumen fluid of goats fed DRB-silage tended to be higher in acetic acid and lower in propionic acid than those fed the other silages. Ammonia in the rumen fluids, urea nitrogen in the blood and the urinary nitrogen excretion were the lowest in goats fed MOL/DRB-silage. As the result, the ratio of retained nitrogen to nitrogen intake was the highest in goats fed MOL/DRB-silage. In conclusion, addition of DRB to napier grass increased DM of silage and decreased the volume of spoilage. The combination of MOL and DRB can improve the fermentation quality and thus enhance the utilization of the silage by goats, more than the MOL or DRB being as a single treatment.