• Journal of Korean Society for Atmospheric Environment
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• 제19권E3호
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• pp.129-136
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• 2003

Effects of inorganic aerosols on the kinetics of the hydroxyl radical reactions with selected aliphatic alkanes have been investigated using the relative rate technique. The relative rates in the absence and presence of aerosols were determined for n-butane, n-pentane, n-hexane, n-octane, and n-decane. P-xylene was used as a reference compound. Inorganic aerosols including (NH$_4$)$_2$SO$_4$, NH$_4$NO$_3$, and NaCl aerosols at two different aerosol concentrations that are typical of polluted urban conditions were tested. Total surface areas of aerosols were 1400 (Condition I) and 3400 $\mu$$m^2$ cm$^{-3}$ (Condition II). Significant changes in the relative rates in the presence of the inorganic aerosols were not observed for the n-butanel/$.$OH, n-pentanel/$.$OH, n-hexanel/$.$OH, n-octanel/$.$OH, and n-decanel/$.$OH reactions versus p-xylenel/$.$OH reaction. These results suggest that the promoting effects depend on the semiconducting property of the aerosols and the nature of the organic compounds.

• Bulletin of the Korean Chemical Society
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• 제15권8호
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• pp.669-673
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• 1994

Coordination isomers of cis-(N-N)Pt(Glu) prepared by reaction of cis-(N-N)Pt($SO_4$) (N-N=2$NH_3$, ethylenediamine(en),(R,R)-1,2-diaminocyclohexane (DACH), N,N,N',N'-tetramethylethylenediamine (TMEDA)) with barium glutamate in water have been monitored and characterized by $^1H-NMR$, $^{13}C-NMR$, IR, and mass spectra. The reaction at room temperature affords the mixture of O,O'-and N, ${\alpha}$ O-chelated platinum(II) complexes. The O,O'-chelate initially formed isomerized to N,${\alpha}$O-chelate on standing for a long time or increasing temperature. The ratio of the two isomers at room temperature depends on the nature of the nitrogen donor coligand (N-N).

• 한국토양비료학회지
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• 제50권2호
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• pp.100-105
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• 2017

Various methods for assessing soil total nitrogen (TN) and inorganic N content have been developed to manage nutrient and to understand N cycle in soil. This paper address the technical procedures in arable soil samples to conduct soil sampling, sample preparation, and measuring total N and inorganic N. Among various methods for measuring soil total nitrogen contents, Kjeldahl distillation and Indophenol blue method have widely used due to reliability and economic advances. Also, two methods can analyze more samples at the same time compared with other nitrogen measuring methods. For evaluating inorganic N content, mainly in forms of nitrate-N ($NO_3{^-}-N$) and ammonium-N ($NH_4{^+}-N$), extraction with a single reagent such as 2M KCl has been employed, followed by Kjeldahl distillation or indophenol blue methods.

• Bulletin of the Korean Chemical Society
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• 제15권8호
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• pp.641-643
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• 1994

Studies of Co(N-N)(3,6-DBSQ)(3,6-DBCat)(N-N=4,7-dimethyl-1 ,10-phenanthroline, 5-chloro-1,10-phenanthroline; DBSQ=di-tert-butylsemiquinonato; DBCat=di-tert-butylcatecholato) have been carried out on the bistability by intramolecular cobalt-quinone electron transfer in solid state. The title complexes dominantly exist as $Co^{III}$(N-N)(3,6-DBSQ)(3,6-DBCat) at room temperature and display a significant bistability on temperature variation. Subtle change in optical spectra and magnetic properties is observed when diimine ligands are changed.

• 한국토양비료학회지
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• 제19권2호
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• pp.139-145
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• 1986

담배식물이 흡수한 질산태질소가 조직중(組織中)에서 환원 되므로서 양(陽)이온과 음(陰)이온성분간(成分間)의 평형(平衡)에 미치는 영향을 구명하기 위하여 질소원(窒素源)을 달리한 배양액(培養液)으로 재배(栽培)하면서 무기(無機) 양음(陽陰)이온총량차이(總量差異)를 조사하고 질소환원(窒素還元) 및 유기산함량(有機酸含量)의 변화(變化)와 이온총량차이(總量差異)와의 관계(關係)를 검토(檢討)한 결과(結果) 1. $NO_3-N$ 배양액에서 자란 식물은 $NH_4-N$ 배양액의 것보다 양(陽)이온총량(總量)이 높았다. 무기음(無機陰)이온총량(總量)은 $NO_3+NH_4$혼합배양액(混合培養液)에서 가장 높게 나타났으나 $NO_3-N$ 배양액에서 가장 낮아서 무기 양음(陽陰)이온총량차이(總量差異)가 가장 컸고 $NH_4{^+}$가 함유된 배양액에서는 무기양음이온 총량차이가 비슷하여 무기이온으로서 거의 이온균형(均衡)이 유지(維持)되었다. 2. 식물체중(植物體中) 유기산(有機酸)은 malic acid의 분포가 가장 컸으며 $NO_3-N$ 배양액식물은 유기산(有機酸)이 다량함유(多量含有)되어 있으나 $NH_4-N$ 또는 혼합배양액(混合培養液)의 것은 거의 검출(檢出)되지 않았다. $NO_3-N$ 배양액식물(培養液植物)은 유기산총량(有機酸總量)이 무기음(無機陰)이온 총량(總量)보다 초과(超過)되어 유기산(有機酸)에 의한 이온균형(均衡)비율이 크나 $NH_4-N$ 배양액식물은 이온균형(均衡)에 차지하는 유기산(有機酸)비율이 극히 소량이었다. 3. $NO_3-N$식물(植物)은 질산환원(窒酸還元)이 왕성하게 진행되므로서 유리(遊離)된 양(陽)이온과의 이온균형(均衡)을 위하여 유기산(有機酸)이 다량(多量) 함유(含有)되었다.

• The Korean Journal of Ceramics
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• 제3권2호
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• pp.124-128
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• 1997

An attempt was made to understand the dissolution and reprecipitation behavior of the constituent phases such as TiC, TiN, and Ti(CN) in TiC-TiN-Ni system. During the liquid-phase sintering the TiC phase was found to dissolve preferentially in Ni binder. The solid-solution phase, Ti(CN), formed around the TiN phase, resulting in a core/rim structure. This result was reproduced when large TiC particles were used with fine TiN particles. The path for the microstructural change in TiC-TiN-Ni system was largely controlled by the difference in the interfacial energy of each phase with the liquid binder phase. The results were discussed with thermodynamic principles.

• The Korean Journal of Ceramics
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• 제4권3호
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• pp.222-226
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• 1998

$Cu_3N$ film deposited on silicon oxide substrate by r.f. reactive sputtering technique. Synthesis and properties of copper nitride film were investigated for its possible application to Cu metallization as adhesive interlayer between copper and $SiO_2. Cu_3N$ film was synthesized at the substrate temperature ranging from $100^{\circ}C$ to $200^{\circ}C$ and at nitrogen gas ratio above $X_{N2}=0.4. Cu_3N, CuN_x$, and FGM-structured $Cu/CuN_x$ films prepared in this work passed Scotch-tape test and showed improved adhesion property to silicon oxide substrate compared with Cu film. Electrical resistivity of copper nitride film had a dependency on its lattice constant and was ranged from 10-7 to 10-1 $\Omega$cm. Copper nitride film was, however, unstable when it was annealed at the temperature above $400^{\circ}C$.

• 한국세라믹학회지
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• 제49권4호
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• pp.325-327
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• 2012

Europium-doped $LaSi_3N_5$ phosphor was synthesized from LaSi/Si/$Si_3N_4/Eu_2O_3$ mixture by nitridation at $1390^{\circ}C$ and additional annealing at $1650^{\circ}C$ for 4 h. The phosphor shows emissions in the green light region with a maximum at 560 nm. With increasing europium content in the general formula $La_{1-z}Eu_zSi_3N_{5-z}O_{1.5z}$ from z = 0.01 to 0.06 there was a maximum emission for z = 0.04 followed by concentration quenching for the highest europium content (z = 0.06).

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.114-114
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• 2011

We report a high-performance and air-stable flexible and invisible semiconductor which can be substitute for the n-type organic semiconductors. N-type organic-inorganic nanohybrid superlattices were developed for active semiconducting channel layers of thin film transistors at low temperature of $150^{\circ}C$ by using molecular layer deposition with atomic layer deposition. In these nanohybrid superlattices, self-assembled organic layers (SAOLs) offer structural flexibility, whereas ZnO inorganic layers provide the potential for semiconducting properties, and thermal and mechanical stability. The prepared SAOLs-ZnO nanohybrid thin films exhibited good flexibility, transparent in the visible range, and excellent field effect mobility (> 7cm2/$V{\cdot}s$) under low voltage operation (from -1 to 3V). The nanohybrid semiconductor is also compatible with pentacene in p-n junction diodes.

• 한국초지조사료학회지
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• 제41권2호
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• pp.84-95
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• 2021

The purpose of this study was to assess the forage productivity and nutritive value of kenaf at different fertilizer application amounts and various stages of maturity. The experiment was conducted from May to September 2020, the amount of 80 kg of kenaf seed/ha was supplied with different types and amounts of nitrogen fertilizer and the plants were harvested at 10-day intervals from different harvesting dates (24^th August and 3^rd, 13^th, 23^rd September). According to the different fertilizer types and application amounts, the highest kenaf height was recorded in the inorganic fertilizer amounts of 200 and 250 kg N/ha and the fresh and DM yield were significantly improved in the inorganic nitrogen amount of 250 kg N/ha. The highest CP and TDN content in the leaf was achieved in the inorganic fertilizer amounts of 150 and 200 kg N/ha, respectively; and the highest TDN content in the stem was also found in the inorganic fertilizer amount of 200 kg N/ha. According to the different harvesting dates, the highest DM ratio was found in the harvesting date of 13th September, the leaf ratio increased with advanced maturity, whereas the stem ratio decreased significantly and the highest DM yield of kenaf was recorded in the harvesting dates of 13^th and 23^rd September. Besides, the highest CP, CF, CA, ADF, NDF and TDN content in the leaf as influenced by different harvesting dates was 15.4, 31.8, 10.2, 22.1, 34.7 and 76.5%, respectively, and the CP, CA, ADF and TDN in stem decreased significantly with advanced maturity of kenaf. In conclusion, the optimal fertilizer amounts and the appropriate harvesting dates for a high forage yield and high-quality kenaf as livestock feed were the inorganic fertilizer application amounts of 200-250 kg N/ha and from 13^th and 23^rd September, respectively.