• Applied Biological Chemistry
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• v.48 no.4
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• pp.418-420
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• 2005

In order to search for biologically active compounds from edible plant sources, the aerial parts of Sajabalssuk (Artemisia herba) were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$, successively. From the EtOAc fraction, four compounds were isolated through the repeated silica gel and ODS column chromatographies. From the results of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as eupatilin (1), jaceosidin (2), apigenin (3) and eupafolin (4). Among them, compounds 3 and 4 were isolated for the first time from Sajabalssuk (Artemisia herba).

• Clean Technology
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• v.26 no.1
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• pp.7-12
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• 2020

Ti-SBA-15 catalysts doped with lanthanide ions (Ln/Ti-SBA-15) were successfully synthesized using conventional hydrothermal method. In addition, they were characterized by XRD, FT-IR, DRS, BET, and PL. The activity of these materials on the photocatalytic decomposition of methylene blue under ultraviolet light irradiation was also examined. Ti-SBA-15 catalysts doped with various lanthanide ions maintained their mesoporous structure. The pore size and pore volume of Ln/Ti-SBA-15 materials decreased but their surface area increased upon the doping of lanthanide ion. Ln/Ti-SBA-15 materials exhibited the type IV nitrogen isotherm with desorption hysteresis loop type H2, which was characteristic of mesoporous materials. The size of hysteresis increased in the doping of lanthanide ions on Ti-SBA-15 material. There was no absorption in the visible region (> 400 nm) regardless of the doping of lanthanide ions to TiO₂ particles, while the broad bands at 220 nm appeared at the Ln/Ti-SBA-15 samples, indicating the framework incorporation of titanium into SBA-15. 1 mol% Pr/ Ti-SBA-15 catalysts showed the highest photocatalytic activity on the decomposition of methylene blue but the Ti-SBA-15 catalysts doped with Eu, Er, and Nd ions showed lower activity compared to pure Ti-SBA-15 catalyst. The PL peaks appeared at about 410 nm at all catalysts while the excitonic PL signal was proportional to the photocatalytic activity for the decomposition of methylene blue.

• Clean Technology
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• v.26 no.4
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• pp.293-303
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• 2020

According to the World Health Organization (WHO), air pollution is a typical health hazard, resulting in about 7 million premature deaths each year. Sulfur dioxide (SO2) is one of the major air pollutants, and the combustion process with sulfur-containing fuels generates it. Measuring SO2 generation in large combustion environments in real time and optimizing reduction facilities based on measured values are necessary to reduce the compound's presence. This paper describes the concentration measurement for SO2, a particulate matter precursor, using a wavelength modulation spectroscopy (WMS) of tunable diode laser absorption spectroscopy (TDLAS). This study employed a quantum cascade laser operating at 7.6 ㎛ as a light source. It demonstrated concentration measurement possibility using 64 multi-absorption lines between 7623.7 and 7626.0 nm. The experiments were conducted in a multi-pass cell with a total path length of 28 and 76 m at 1 atm, 296 K. The SO2 concentration was tested in two types: high concentration (1000 to 5000 ppm) and low concentration (10 ppm or less). Additionally, the effect of H2O interference in the atmosphere on the measurement of SO2 was confirmed by N2 purging the laser's path. The detection limit for SO2 was 3 ppm, and results were compared with the electronic chemical sensor and nondispersive infrared (NDIR) sensor.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3321-3330
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• 2012

The complexation characteristics of mixed [2 + 2'] calix[4]aryl derivatives (3 and 4) with alkali metal cations were investigated by the mPW1PW91 (hybrid HF-DF) calculation method. The total electronic and Gibbs free energies of the various complexes (cone, partial-cone, 1,2-alternate, and 1,3-alternate) of sodium and potassium cations with 3 and 4 were analyzed and compared. The structures of the endo- or exo-complexes of the alkali metal cation with the host 3 were optimized using the mPW1PW91/6-31G(d) method, followed by mPW1PW91/6-311+G(d) calculations. The structures of the endo- or exo-complexes of the alkali metal cation with the host 4 were optimized using the mPW1PW91/6-31G(d,p) method. The mPW1PW91 calculated relative energies of the various conformations of the free hosts (3 and 4) suggest that the cone conformers of 3 and 4 are the most stable. The mPW1PW91calculations also suggest that the complexation efficiencies of the sodium ion with hosts 3 and 4 are about 24 and 27 kcal/mol better than those of the potassium ion, respectively. These trends are in good agreement with the experimental results. The exo-complexation efficiencies of the sodium ion toward the conformers of hosts 3 and 4 are roughly 14 and 17 kcal/mol better than those for the endo-$Na^+$-complexes of 3 and 4, respectively. The exo-complexation of the cone isomer of 3 with cation could be confirmed by the differences of the diagnostic C=O bands in the free host and its complex's IR spectra.

• Journal of the Korean Ceramic Society
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• v.44 no.2 s.297
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• pp.124-131
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• 2007

In this study, first the ADU gel particle, an intermediate for final $UO_2$ kernel of a HTGR nuclear fuel, was prepared from sol-gel method using the broth solution which was made by mixing of the uranyl nitrate, poly vinyl alcohol and tetra-hydrofurfuryl alcohol. The prepared dried-ADU gel particles were converted to the $UO_2\;via\;UO_3$ from thermal treatment with the 4% $H_2$ atmosphere. The sizes of the spherical liquid droplets appeared $1900{\sim}2100{\mu}m$, and the harmony between the flow rate of the broth solution and the frequency and the amplitude of a vibrating system are important factors for the spherical ADU gel particles via the mono size spherical droplets. From the XRD and FT-IR analyses, the prepared ADU gel particles were judged to be a $UO_3{\cdot}xNH_3{\cdot}yH_2O$ form, and the most important factor during the thermal treatment of the dried-ADU gel particle must be avoided a rapidly heating rate in the range of $180{\sim}400^{\circ}C$, and the heating rate should be kept below $5^{\circ}C/min$.

• Journal of the Korean Applied Science and Technology
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• v.7 no.2
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• pp.19-32
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• 1990

Lipid levels in the tissues of liver and intestines of O.bartrami amounted to 40.0% and 1.5%. The new compounds was found to be ethyl acylates, from a deduction of their detailed $^1H-nuclear$ magnetic resonance(NMR) and $^{13}C-NMR$ as well as infra red spectra (IR). The fatty acid composition of total lipids were mainly composed of C16:0(19.0%), C18:1(16.2%) and $C22:6{\omega}3$(15.7%), followed by C20:1(9.4%), C22:1(6.4%) and C18:0(5.4%). New compound A and B were seemed to derived from the cleavage of glycerol moieties of triglycerides by microbial activities during storage in a frozen state. Compound A contained C16:0(38.2%), C18:1(13:4%), C20:1(13.3%) and C22:1(11.7%) as major components, while compound B predominantly comprised polyunsaturated fatty acid such as $C20:5{\omega}3$ (41.2%) and $C22:6{\omega}3$(36.1%). In both compounds small amounts of odd numbered fatty acids were also detected ($3.8{\sim}2.2%$).

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2523-2528
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• 2014

In the present study, at first, azo Schiff base ligand of (N,N'-bis(5-phenylazosalicylaldehyde)-ethylenediamine) ($H_2L$) has been synthesized by condensation reaction of 5-phenylazosalicylaldehyde and ethylenediamine in 2:1 molar ratio, respectively. Then, its cobalt complex (CoL) was synthesized by reaction of $Co(OAc)_2{\cdot}4H_2O$ with ligand ($H_2L$) in 1:1 molar ratio in ethanol solvent. This ligand and its cobalt complex containing azo functional groups were characterized using elemental analysis, $^1H$-NMR, UV-vis and IR spectroscopies. Subsequently, the interaction between native calf thymus deoxyribonucleic acid (ct-DNA) and CoL complex was investigated in 10 mM Tris/HCl buffer solution, pH = 7 using UV-vis absorption, thermal denaturation technique and viscosity measurements. From spectrophotometric titration experiments, the binding constant of CoL complex with ct-DNA was found to be $(2.4{\pm}0.2){\times}10^4M^{-1}$. The thermodynamic parameters were calculated by van't Hoff equation.The enthalpy and entropy changes were $5753.94{\pm}172.66kcal/mol$ and $43.93{\pm}1.18cal/mol{\cdot}K$ at $25^{\circ}C$, respectively. Thermal denaturation experiments represent the increasing of melting temperature of ct-DNA (about $0.93^{\circ}C$) due to binding of CoL complex. The results indicate that the process is entropy-driven and suggest that hydrophobic interactions are the main driving force for the complex formation.

• Journal of the Korean Chemical Society
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• v.57 no.2
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• pp.246-251
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• 2013

With -$OCH_2CO$- as a linker, a non ${\beta}$-substituted cationic bisporphyrin (4a) and a ${\beta}$-substituted cationic bisporphyrin (4b) were prepared through methylation of the intermediate which was obtained from ${\beta}$-amino-5,10,15,20-tetra (4-cyanophenyl) porphyrin or 5-hydroxylphenyl-10,15,20-tris(4-cyanophenyl) reacting with 5-hydroxy-10,15,20-trispyridinylporphyrin. Their structures were confirmed by $^1H$ NMR, IR, UV-vis, MS and elemental analysis. DNA photocleavage ability and the singlet oxygen ability of those cationic bisporphyrins were investigated. DNA photocleavage activity of ${\beta}$-substituted cationic bisporphyrin was significantly weaker than that of $H_2TMPyP$, but similar to that of non ${\beta}$-substituted cationic bisporphyrin. While 4a and 4b showed substantial photocleavage activities toward DNA, with 68% and 66% observed at 10 ${\mu}M$. The assessment of indirectly measured $^1O_2$ production rates against $H_2TMPyP$ were described and the relative singlet oxygen production yields were: free cationic bisporphyrins > $H_2TMPyP$. The results showed the cationic bisporphyrins with ${\beta}$-substitution and non ${\beta}$-substitution could be developed as potential photodynamic agents.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1527-1527
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• 2001

Glucose, fructose and sucrose being the main sugars that can be found in natural fruit juice. Many instrumental methods, such as GC, LC, electrochemical or spectrometric methods provide information about both the total content of sugars and the specific concentration of each carbohydrate[1]. The simplicity of sample handling and measurement in the near IR(NIR) wavelength region, which allows the use of long pathlength, optical glass cells and optical fibers, makes NIR a good alternative for sugar determination [2]. In the present study, six varieties of persian grapes were harvested at intervals through august to october and analysed for sugars by NIR. The results were processed by principal component regression (PCR) and partial least squares (PLS) analysis. Sample juice was prepared by squeezing through gauze from crashed grape. This solution was treated by zinc ferrocyanide prior to analysis in order to eliminate colored compounds and all optically active nonsugar substances. For glucose and fructose the most characteristic wavelengths were 1456nm corresponding to the first harmonic O-H stretching and the second at 2062nm corresponding to O-H stretching and deformation; secondary characteristic combination bands were also seen at 2265 nm (O-H and C-C stretching) and at 2240 nm (C-H and C-C stretching). However these spectra were taken over a wavelength range from 1100-2500nm at room temperature of 25-$30^{\circ}C$. To test the accuracy of the described procedure, samples of six varieties of grape were analysed by the proposed NIR and a standard method[2]. Good agreement were found between these two sets of the results. To perform the recovery studies , samples of grape juices previously analysed by the proposed method, were spiked with known amounts of each individual sugars and then analysed again. Relative standard deviations varied from 1.4 to 1.8% for six independent measurements of individual and total sugar concentration. In the analysis of real and synthetic samples, precise and accurate results were obtained , providing accuracy errors lower than 1.9% in all cases. Average recoveries of ${97}{\pm}{4%}$ for total sugar and between ${95}{\pm}{5%}$ and ${99}{\pm}{2%}$ for sing1e sugars demonstrate the applicability of the methodology developed to the direct analysis of grape Juice.

• Applied Biological Chemistry
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• v.48 no.4
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• pp.382-387
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• 2005

The aim of this study was to identify binding properties of germanium (Ge) in Germanium-fortified Yeast using optimum manufacturing process. The ratio of yeast cell and germanium solution was 1 : 0.5 (50%), and pH 6.5, $35^{\circ}C$ and 20 h during fermentation, and Germanium-fortified Yeast produced. In results of the XRD, NMR and FT-IR analysis, it was different adding inorganic Ge $(GeO_2)$ during fermentation process from transformed into germanium in Germanium-fortified Yeast. And germanium concentration was not shown any difference before and after in the dialysis test with SGF (simulated gastric fluids). Therefore, Germanium-fortified Yeast of Geranti made by using biosynthetic technology was considered that transformed into organic properties during fermentation process. And, this result showed that Germanium-fortified Yeast was not dissociated under SGF (simulated gastric fluids) condition because of its structural binding safety. Thus, Germanium-fortified Yeast was transformed into organic germanium during biosynthetic cultivation. It is expected that this Germanium-fortified Yeast can be applied as a new dietary functional materials for cellular immunity, recovery of injured cells and immune system, and possible anticancer activities by activation immune cells like macrophage.