• Bulletin of the Korean Chemical Society
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• v.23 no.12
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• pp.1790-1800
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• 2002

The DNA nucleosides(dA, dC, dG, dT)bound to gold nanoparticles (~13 nm) in aqueous solution has been studied as a probe by the SERS and their coordination structures have been proposed on the basis of them. According to UV-Visible absorption of gold nanoparticles after modifying with DNA nucleosides, the rates of absorption of dA, dC, and dG were much faster than that of dT as monitored by the aggregation kinetics at 700 nm. These data indicated that the nucleosides dA, dC, and dG had a higher affinity for the gold nanoparticles surface than nucleoside dT. As the result of SERS spectra, the binding modes of each of the nucleosides on gold nanoparticles have been assigned. A dA binds to gold nanoparticles via a N(7) nitrogen atom of the imidazole ring, which the C(6)-$NH_2$ group also participates in the coordination process. In the case of dC, it binds to the gold surface via a N(3) nitrogen atom of the pyrimidine ring with a partial contribution from the oxygen of C(2)=O group. A coordination of dG to the gold surfaces is also proposed. Although the dG has the two different nitrogens of a pyrimidine ring and the amino group, the N(1) nitrogen atom of a pyrimidine ring has a higher affinity after the hydrogen migrates to the amino group. Conversely, dT binds via the oxygen of the C(4)=O group of the pyrimidine ring. Accordingly, these data suggest that the nitrogen atom of the imidazole or the pyrimidine ring in the DNA nucleosides will bind more fast to the gold nanoparticles surfaces than the oxygen atom of the carbonyl group.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.4
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• pp.280-286
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• 2021

The objective of this study was to prove the effect of pig slurry application with charcoal on nitrogen use efficiency (NUE), feed value and ammonia (NH₃) emission from maize forage. The four treatments were applied: 1) non-pig slurry (only water as a control), 2) only pig slurry application (PS), 3) pig slurry application with large particle charcoal (LC), 4) pig slurry application with small particle charcoal (SC). The pig slurry was applied at a rate of 150 kg N ha^-1, and the charcoal was applied at a rate of 300 kg ha-1 regardless of the size. To determine the feed value of maize, crude protein, dry matter intake, digestible dry matter, total digestible nutrient, and relative feed value were investigated. All feed value was increased by charcoal treatment compared to water and PS treatment. Also, the NUE for plant N was significantly higher in charcoal treatments (LC and SC) compared to PS treatment. On the other hand, there is no significant difference for feed value and NUE between LC and SC. The NH₃ emission was significantly reduced 15.2% and 27.9% by LC and SC, respectively, compared to PS. Especially, SC significantly decreased NH₃ emission by 15% compared to LC. The present study clearly showed that charcoal application exhibited positive potential in nitrogen use efficiency, feed value and reducing N losses through NH₃ emission.

• The Korean Journal of Mycology
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• v.22 no.2
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• pp.153-159
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• 1994

Effects of some sources on the vegetative growth of Naematoloma sublateritium (Fr.) Karst. were investigated using liquid and solid culture media. Temperature, pH, carbohydrates as carbon sources, amino acids as nitrogen sources, the optimal carbon/nitrogen ratio, mineral element and organic acids were studied for good mycelial growth. We could improve a new semisynthetic medium for mycelial growth in N. sublateritium.

• Journal of the Korean institute of surface engineering
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• v.30 no.4
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• pp.255-261
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• 1997

Thin film batteries can be used as a micro power source for electronic in which minute power is needed. In this study, lithium phosphorous oxynitride(LIPON) thin films were deposited as an eletrolyte for lithium ion batteries using RF magentron sputtering of lithium phosphate in N2. Ti was also added into the LIPON films as a second network former to enhance the ioinc conductivity of the films. The optimum conditions for LIPON film deposition were sought and the electrolyte with the conductivity of $2.5 \times 10^{-6}$S/cm was obtained at the condition of RF power 4.4 W/$\textrm{cm}^2$, process pressure 10 mtorr and pure nitrogen ambience. Furthermore, the conductivity of LIPON films was increased from $2.5 \times 10^{-6}$S/cm to $8.6 \times 10^{-6}$S/cm by the doping of 2.4at.% Ti. It was also found that by adding Ti to LIPON films, Li content was increased and nitrogen content that reported having the cross-linking effect on LIPON films was also increased as confirmed XPS.

• Journal of the Korean Vacuum Society
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• v.6 no.S1
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• pp.75-79
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• 1997

Optical and mechanical characteristics of $TiO-2, ZrO_2 \;and\; SiO_xN_y$ thin films prepared by ion assisted deposition (IAD) were investigated. IAD films were bombarded by Ar or nitrogen ion beam from a Kaufman ion source while they were grown in as e-beam evaporator. The result shows that the Ae IAD increases the refractive index and packing density of $TiO_2 films close to those of the bulk. For $ZrO_2$ films the Ar IAD increases the average refractive index decreases the negative inhomogeneity of refractive index and reverses to the positive inhomogeneity. The optical properties result from improved packing density and denser outer layer next to air The Ar-ion bombardment also induces the changes in microstructure of $ZrO_2$ films such as the preferred (111) orientation of cubic phase increase in compressive stress and reduction of surface roughness. Inhomogeneous refractive index SiOxNy films were also prepared by nitrogen IAD and variable refractive index of $SiO_xN_y$ film was applied to fabricate a rugate filter.

• Korean Journal of Soil Science and Fertilizer
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• v.11 no.1
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• pp.1-7
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• 1978

Laboratory and pot experiment were carried out to find the symbiotic nitrogen fixing activities and the yield of dry matter on the several selected wild soybean plant. 1. Very high acetylene reducing(nitrogen fixing)activities were observed in isolated strains of Rhinchosis volubilies Lour. (924 nmole), Desmodium oldhami Oliver (844 nmole) and Glycine soja s. et z. (271 nmole/test tube/hr) while Rhizobium japonicum was only 0.6 nmole/test tube/hr. 2. On the serological reaction, eight isolated Rhizobium strains were sufficiently different to distinguish from the Rhizobium japonicum. 3. On the pot experiment with Glycine soja s. et z., A. Number of total nodules were higher in NPK+rice straw+Ca+Mo than in NoPK. However, little differences were observed in mumber of effective nodules. B. Yield of dry matter was increased with increasing of nitrogen content in plants. C. Estimated amount of fixed nitrogen in plant by an individual nodule was higher in NoPK than in NPK+rice straw+Ca+Mo.

• Journal of Animal Environmental Science
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• v.15 no.3
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• pp.263-270
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• 2009

A study was conducted to determine the effects of seed mixture and nitrogen application levels on botanical composition and forage productivity in grazing pasture. Legume forage have the ability to take nitrogen from the atmosphere and convert it into a form usable by plants. Including legumes in mixtures with grass lowers the amount of nitrogen fertilizer required to produce forages. Dry matter (DM) yield of grass-legume mixtures was more than that of grass mono-cultivated and grass+white clover+red clover mixtures was the highest as 17,391 kg/ha in legume mixture (P<0.01). The highest DM yield was in N-200 kg/ha, but it was similar between N-100 kg/ha(15,128) and N-200 kg/ha (16,017). The large decline in the proportion of grass during April to June in 2004 probably was due to the drought and summer depression in grass-legume mixtures. Grass proportions decreased by 8.2% after 2 year, and white clover was dominated in grass-white clover mixture by May 2005. Crud protein (CP) content tends to increase with increased nitrogen application level.

• Journal of the Korean Vacuum Society
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• v.19 no.1
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• pp.14-21
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• 2010

Ge is one of the attractive channel materials for the next generation high speed metal oxide semiconductor field effect transistors (MOSFETs) due to its higher carrier mobility than Si. But the absence of a chemically stable thermal oxide has been the main obstacle hindering the use of Ge channels in MOS devices. Especially, the fabrication of gate oxide on Ge with high quality interface is essential requirement. In this study, $HfO_xN_y$ thin films were prepared by plasma-enhanced atomic layer deposition on Ge substrate. The nitrogen was incorporated in situ during PE-ALD by using the mixture of nitrogen and oxygen plasma as a reactant. The effects of nitrogen to oxygen gas ratio were studied focusing on the improvements on the electrical and interface properties. When the nitrogen to oxygen gas flow ratio was 1, we obtained good quality with 10% EOT reduction. Additional analysis techniques including X-ray photoemission spectroscopy and high resolution transmission electron microscopy were used for chemical and microstructural analysis.

• Korean Journal of Environmental Agriculture
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• v.31 no.4
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• pp.308-312
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• 2012

BACKGROUND: The nutrient balance in Korea during 1985-2006 had continually increased and maintained the highest levels among OECD countries. The use of green manure crops such as barley and hairy vetch is common practice for reducing chemical fertilizer application and maintaining soil fertility. However, green manure crops can also be used as a livestock feeding material which may reduce nutrient balance in the national scale. We calculated nitrogen and phosphate balance under green manure-rice cultivating system where all green manure was removed and used for feeding livestock. METHODS AND RESULTS: The barley and hairy vetch grown in pure stands or in mixtures with different sowing rates were tested for rice cultivation without chemical fertilization. The conventional fertilization (NPK) for rice cultivation was selected to compare nutrient balance with green manure-rice cultivation. Nitrogen and phosphate balance were calculated according to the surface balance method of the PARCOM guidelines. Total aboveground biomass of mixture (barley and hairy vetch) was higher compared to that of pure barley or hairy vetch. Among the mixture with barley and hairy vetch, the highest aboveground biomass was observed in B75H25 (barley 75%+hairy vetch 25%). The nitrogen and phosphate balance in the B75H25 mixture was-104 kg N/ha and-50.3 kg P/ha, respectively. CONCLUSION(S): The barley and hairy vetch mixture proved to be a very effective strategy for biomass production of green manure. The amount of nitrogen and phosphate fertilizer to be applied is estimated to be 104 kg N/ha and 50.3 kg P/ha in order to maintain soil fertility if all green manure and rice straw were removed from rice field for livestock feeding.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.2
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• pp.169-176
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• 1985

Six analytial methods for determing the available nitrogen in soils were tested to predict the optimum fertilizer rate for the flue-cured tobacco and to test the fertility level of soils for tobacco. All methods, nitrifiable $NO_3-N$ value for 2 and 4 weeks incubation, UV absorption value at 260nm and N-value in acid digestion of 0.01 M-$NaHCO_3$ extracts, N-value extracted in boiling with $CaCl_2$ solution, and autoclave-extractable $NH_4-N$ value in 0.01 M-$CaCl_2$, were closely correlated with total nitrogen uptake as well as yield. Therefore available nitrogen indices determined from above 6 analysis method could be used for the predicting of tobacco yield without fertilizer, criteria for fertility class, and recommendable range of optimum fertilization.