• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.5
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• pp.483-491
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• 1992

Plasma silicon oxynitride film has been applied as a final passivation layer for semiconductor devices, because it has high resistance to humidity and prevents from alkali ion's penetration, and has low film stress. Structure properties of plasma silicon oxynitride film have been studied experimentally by the use of FT-IR, AES, stress gauge and ellipsometry. In this experiment,Si-N bonds increase as NS12TO/(NS12TO+NHS13T) gas ratio increases. Peaks of Si-N bond, Si-H bond and N-H bond were shifted to high wavenumber according to NS12TO/(NS12TO+NHS13T) gas ratio increase. Absorption peaks of Si-H bond were decreased by furnace anneal at 90$0^{\circ}C$. The atomic composition of film represents that oxygen atoms increase as NS12TO/(NS12TO+NHS13T) gas ratio increases, to the contrary, nitrogen atoms decrease.

• Journal of Photoscience
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• v.11 no.3
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• pp.107-113
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• 2004

Synthesis, absorption and fluorescence properties of 3-methyl indole (1), N-(benzenesulfonyl)-3-(3-oxo-but-1-enyl)-indole (2) and 1H-3-(3-oxo-but-1-enyl)-indole (3) are described. Extended conjugation at C-3 of indole as in 3 causes moderate resolution of $^1L_a$ and $^1L_b$ bands. However, 2 having an electron-withdrawing group at indolic nitrogen shows only the $^1L_a$ band. While the $^1L_b$ band largely remains solvent polarity independent, the $^1L_a$ band undergoes moderate red shift in polar solvents. The fluorescence in 2 and 3 originates from the $L_b$ transition. Additionally, interaction of 2 and 3 with BSA indicates that these compounds bind to the hydrophobic site of BSA with the formation of a highly fluorescent BSA-probe complex.

• Journal of the Optical Society of Korea
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• v.16 no.4
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• pp.325-330
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• 2012

Differential absorption LIDAR (DIAL) is frequently used for atmospheric gas monitoring to detect impurities such as nitrogen dioxide, sulfur dioxide, iodine, and ozone. However, large differences in the on- and off-line laser wavelengths can cause serious errors owing to differential aerosol scattering. To resolve this problem, we have developed a new DIAL system for iodine vapor measurements in particular. The suggested DIAL system uses only one laser under seeded and unseeded conditions. To check the detection-sensitivity and error effects, we compared the results from a system using two seeded lasers with those from a system using a seeded and an unseeded laser. We demonstrate that the iodine concentration sensitivity of our system is improved in comparison to the conventional two seeded or two unseeded laser combinations.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.103-107
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• 2016

This study aims to select the most appropriate poplar clones for planting on short rotation coppice poplar plantations in a riparian area. The research investigated biomass production, nitrogen and carbon absorption with 2-year-old poplar (Populus spp.) clones including P. euramericana clone Eco28, P. deltoides hybrid clone 97-18, and P. alba ${\times}$ P. glandulosa hybrid clone 72-30. The average number of stems per stump was five and P. euramericana clone Eco28 had the greatest average number of live stems per stump with 5.9. The average stem diameter was 23.2 mm, and P. deltoides hybrid clone 97-18 achieved the largest average diameter with 25.4 mm. The average annual above-ground biomass production of Populus deltoides hybrid clone 97-18 was 16.1 ton/ha/year, followed by P. alba ${\times}$ P. glandulosa hybrid clone 72-30 and P. euramericana clone Eco28, 12.3 and 5.4 ton/ha/year, respectively. The average annual nitrogen uptake of poplar clones was 46.5 kg/ha/year. P. alba ${\times}$ P. glandulosa hybrid clone 72-30 had the highest average, 63.1 kg/ha/year. The average of annual carbon absorption was estimated 5.3 ton/ha/year and Populus deltoides hybrid clone 97-18 showed the best results with 7.7 ton/ha/year. Based on the results given above, P. deltoides hybrid aspen clone 97-18 is considered as the most suitable poplar clones for wood biomass production on riparian areas.

• Journal of the Korean Magnetics Society
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• v.15 no.2
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• pp.142-147
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• 2005

The embrittlement of fast neutron-irradiated reactor pressure vessel (RPV) steels was investigated by X-ray diffraction patterns at room temperature and $M\ddot{o}ssbauer$ spectroscopy at room- and liquid nitrogen-temperature. Neutron fluence on the samples were $10^{12},\;10^{13},\;10^{14},\;10^{15},\;10^{16},\;10^{17},\;10^{18}\;n/cm^2$. The X-ray diffraction patterns showed that the structure of the neutron unirradiated sample was bcc type, where as but the neutron irradiated samples with the fluence higher than $10^{17}\;n/{\cal}cm^2$ were so severely damaged, that bcc type structure disappeared. The $M\ddot{o}ssbauer$ spectra of all samples showed superposition of two or more sextets. In this paper all $M\ddot{o}ssbauer$ spectra were fitted by three set of sextet. The isomer shift and quadrupole splitting values were found around zero. At liquid nitrogen temperature, magnetic hyperfine field and absorption area increase rapidly S 1 sextet in the samples of $10^{17}\~10^{18}\;n/{\cal}cm^2$ neutron fluences. And at room temperature, magnetic hyperfine field and absorption increased rapidly at SI sextet in the samples of $10^{17}\~10^{18}\;n/{\cal}cm^2$ neutron fluences. This rapid increase of magnetic hyperfine field and absorption area were inferred to be caused by the change of $^{56}Fe,\;^{55}Mn$ into $^{57}Fe$ due to by neutron irradiation.

• Journal of Ginseng Research
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• v.44 no.4
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• pp.627-636
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• 2020

Background: Cultivation of medicinal crops, which synthesize hundreds of substances for curative functions, was focused on the synthesis of secondary metabolites rather than biomass accumulation. Nutrition is an important restrict factor for plant growth and secondary metabolites, but little attention has been given to the plasticity of nutrient uptake and secondary metabolites synthesis response to soil nitrogen (N) change. Methods: Two year-field experiments of Sanqi (Panax notoginseng), which can synthesize a high level of saponin in cells, were conducted to study the effects of N application on the temporal dynamics of biomass, nutrient absorption, root architecture and the relationships between these parameters and saponin synthesis. Results: Increasing N fertilizer rates could improve the dry matter yields and nutrient absorption ability through increasing the maximum daily growth (or nutrient uptake) rate. Under suitable N level (225 kg/ha N), Sanqi restricted the root length and surface and enhanced the root diameter and N uptake rate per root length (NURI) to promote nutrient absorption, but the opposite status of Sanqi root architecture and NURI was found when soil N was deficient. Furthermore, increasing N rates could promote the accumulation of saponin in roots through improving the NURI, which showed a significant positive relationship with the content of saponin in the taproots. Conclusion: Appropriate N fertilizer rates could optimize both root architecture and nutrient uptake efficiency, then promote both the accumulation of dry matter and the synthesis of saponins.

• Journal of Photoscience
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• v.11 no.1
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• pp.19-23
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• 2004

The sharp-line absorption spectrum of microcrystalline samples of cis-[Cr(cycb)$Cl_2$]Cl (cycb=rac-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) has been measured between 13000 and $16000 cm^{-1}$ at temperatures down to 5K. The 77K emission and excitation spectra, and 298 K infrared and visible absorption spectra have also been measured. The nine electronic bands due to spin-allowed and spin-forbidden transitions were assigned. Using the observed transitions, a ligand field analysis has been performed to probe the ligand field properties of coordinated atoms in the title chromium(III) complex. The zero-phonon line in the sharp-line absorption spectrum splits into two components by $240 cm^{-1}$ , and the $large ^2$$_E{g}$ splitting can be reproduced by the modem ligand field theory. It is confirmed that nitrogen atoms of the macrocyclic cycb ligand have a strong $\sigma$-donor character, but chloride ligand has weak $\sigma$- nd $\pi$-donor properties toward chromium(III) ion.n.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.3
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• pp.385-392
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• 2000

The adsorption ability of dyes on chitin, a natural polymer was investigated for decolorization of dye wastewater. Chitin was manufactured in lab by decalcification in dilute aqueous HCI solution and deproteination in dilute aqueous NaOH solution with shrimp shells. Absorbance of residue solution of dyebaths after dye adsorptions of chitin were measured in varieties of dye concentration and dipping periods. Four kinds of dyestuffs were used, C.I.Acid Blue 29. C.I.Direct Blue 6, C.I.Reactive Orange 12 and C.I.Basic Red 18. When chtin 1g was dipped in 0.05% of dyebath with stirring, maximum adsorption ratio of each kind of dyes was exhibited as 91.6% for C.I.Acid Blue 29, 95% for C.I.Direct Blue 6, 58.2% for C.I.Reactive Orange 13 and 75.8% for C.I.Basic Red 19. It shows that chitin has better adsorption abilities of ionic dyes of acid, direct and basic dye than non-ionic reactive dye. And chitin has better adsorption abilities of anionic acid direct dyes than cationic basic dye because of the presence of nitrogen atoms. All kinds of dyestuffs used showed speedy absorption effects by chitin, so chitin can absorb much amount of dyes in 5 mimutes reach to equilibrium of adsorption in 2 hours after dipping. Basic dye was absorbed the most speedily in 5 minutes, although maximum adsorption ratio is not high. That reason can be thought that chitin surface is essentially negatively charged due to polar funtional groups.

• Bulletin of the Korean Chemical Society
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• v.26 no.6
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• pp.903-908
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• 2005

The sharp-line absorption and emission spectra of $(H_{13}O_6)${$trans-[Cr(Me_2tn)_2Br_2]$}$_2Br_2(ClO_4)\;(Me_2$tn = 2,2-dimethyl-1,3-diaminopropane) have been measured between 13000 $cm^{-1}$ and 16000 $cm^{-1}$ at 5 K. The 298 K infrared and visible absorption spectra have also been measured. The nine electronic bands due to spin-allowed and spin-forbidden transitions were assigned. Using observed transitions, a ligand field analysis has been performed to probe the ligand field properties of coordinated atoms in the title chromium(III) complex ion. The zero-phonon line in the sharp-line absorption spectrum splits into two components by 286 $cm^{-1}$, and the large $^2E_g$ splitting can be reproduced by the modern ligand field theory. It is confirmed that nitrogen atoms of the Me2tn ligand have a strong $\sigma$-donor character, but the bromide has weak $\sigma$- and $\pi$-donor properties toward chromium(III) ion.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.198.2-198.2
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• 2016

Reactive oxygen and nitrogen species (RONS) can be generated by using non-thermal atmospheric pressure plasma jet which have profound biomedical applications [1, 2]. In this work, reactive oxygen species like hydroxyl radical (OH) are generated by using non-thermal direct plasma jet above water surface using Ar gas and their properties have been studied using ultraviolet absorption spectroscopy. OH radicals are found to be generated simultaneously with the discharge current with concentration of $2.7{\times}1015/cm3$ at 7mm above water surface while their persistence time have been measured to be $2.8{\mu}S$. In addition, it has been shown that plasma initiated ultraviolets play a major role to generate RONS inside water. Further works are going on to measure the temporal behavior of OH and $O2^*-$.