• The Korean Journal of Food And Nutrition
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• v.3 no.2
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• pp.169-176
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• 1990

Effects of metal chelating agents and metal ions on the volatile substance of cooked oil with chicken and pork mixture meat were examined by chemical analysis and sensory test. The addition of Na-tripolyphosphate(Na-TPP) to chicken and pork mixture meat increased the amount of H2S among volatiles evolved during cooking but decreased that of volatile carbonyl compounds(VCC) This treatment enhanced meat flavor in cooked oil with chicken and pork mixture. It was recognized that the increase in Ha5 evolution was caused by the rise of pH value. On the contrary cupric ion produced a negative effect on the production of chicken and pork mixture meat flavor and this addition increased VCC and TBA value. Other metal chelating agents such as citric acid, phytic acid and EDTA, provided the same results as Na-TPP. It was supposed that these phenomena were attributable to the chelating action to metal prooxidant in mixture meat at could be concluded that a proper evolution of H2S and protection against lipid oxidation during cooking were important to produce an excellent chicken and pork mixture meat flavor.

• Journal of the Korean Ceramic Society
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• v.55 no.4
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• pp.307-324
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• 2018

Rechargeable lithium-ion batteries (LIBs) have been rapidly expanding from IT based applications to uses in electric vehicles (EVs), smart grids, and energy storage systems (ESSs), all of which require low cost, high energy density and high power density. The increasing demand for LIBs has resulted in increasing price of the lithium source, which is a major obstacle to wider application. To date, the possible depletion of lithium resources has become relevant, giving rise to the interest in Na-ion batteries (NIBs) as promising alternatives to LIBs. A lot of transition metal compounds based on conversion-alloying reaction have been extensively investigated to meet the requirement for the anodes with high energy density and long life-time. In-depth understanding the electrochemical reaction mechanisms for the transition metal compounds makes it promising negative anode for NIBs and provides feasible strategy for low cost and large-scale energy storage system in the near future.

• Bulletin of the Korean Chemical Society
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• v.7 no.3
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• pp.201-204
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• 1986

Reduction of N-arylpyridinium compounds by $NaBH_4$ gave mixtures of the corresponding 1,2-dihydropyridine(major) and 1,4-dihydropyridine(minor), whereas similar reduction by $Na_2S_2O_4$ produced 1,4-dihydropyridines regioselectively. The proportion of 1,4-isomer in the product by $NaBH_4$ reduction appeared to increase with the electron-donating ability of N-aryl groups. When the N-aryl group is p-methylphenyl, p-ethylphenyl or p-methoxyphenyl, the 1,2-dihydropyridines in ethanol-water (4:1) solutions isomerized to the corresponding 1,4-dihydropyridines. N-(p-methylphenyl)-1,2-dihydropyridine and N-(p-ethylphenyl)-1,2-dihydropyridine in solid state also isomerized to the corresponding 1,4-dihydropyridines. The different behaviors of reduction among N-arylpyridiniums and isomerization of the reduction products depending on the substituent in N-aryl group were explained in terms of difference in the electronic effects of the substituents.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.208-210
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• 2002

Baker's yeast was cultured with $Na_2SeO_3$. Selenium compounds in yeast were extracted and analyzed by size exclusion chromatography. Selenium was broadly distributed in the fraction of protein. For the inhibition test of MMP-l induction, selenium containing compounds was fractioned by ultrafiltration

• Analytical Science and Technology
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• v.13 no.1
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• pp.72-80
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• 2000

The HS/GC/MS method was performed to analyze the volatile organic compounds in waste sludge samples. This study was performed to establish the fundamental data by studying the effects of salt, equilibrium temperature and time in the volatile organic compounds analysis. The presence of salts have been found to increase the sensitivity. The peak area is increased from 1.07 to 2.61 times by adding the salts to the water sample, compared with a salt tree sample. The recoveries of target compounds have found between 90% and 127% at sample temperature of $85^{\circ}C$ for 30 min. This HS/GC/MS method can be applied to analyze the volatile organic compounds and organohalo compounds in the environmental matrix.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.6
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• pp.674-681
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• 2008

Silver as a metal catalyst has been used to remove odorous compounds. In this study, silver particles in nano sizes ($5{\sim}30nm$) were prepared on the surface of $NaHCO_3$, the supporting material, using a sputtering method. The silver nano-particles were dispersed by dissolving $Ag-NaHCO_3$ into water, and the dispersed silver nano-particles in the aqueous phase was applied to remove inorganic odor compounds, $NH_3$ and ${H_2}O$, in a scrubbing reactor. Since ammonia has high solubility, it was removed from the gas phase even by spraying water in the scrubber. However, the concentration of nitrate (${NO_3}^-$) ion increased only in the silver nano-particle solution, implying that the silver nano-particles oxidized ammonia. Hydrogen sulfide in the gas phase was rapidly removed by the silver nano-particles, and the concentration of sulfate (${SO_4}^{2-}$) ion increased with time due to the oxidation reaction by silver. As a result, the silver nano-particles in the aqueous solution can be successfully applied to remove odorous compounds without adding additional energy sources and producing any harmful byproducts.

• Journal of the Korean Chemical Society
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• v.35 no.5
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• pp.534-538
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• 1991

A procedure for spectrophotometric determination of traces of boron in high-purity trichlorosilane (TCS) is proposed utilizing an adsorptive separation. NaCl is chosen as an Lewis base adsorbent which forms a complex with boron compounds in TCS, and is well dissolved in sulfuric acid-quinalizarin color-forming agent without causing an interference in colorimetric measurements. The proposed adsorptive separation method is free from the formation of silica gel and gas bubbles during the analysis of TCS. The method reveals that the boron concentration in a semiconductor grade TCS is 6.1 ${\mu}$g/l within the standard deviation of ${\pm}$20%. On the other hand, the boron concentration of the purified TCS which is separated from NaCl-boron compounds complex is reduced to 0.2 ${\mu}$g/l, showing the efficient applicability of NaCl to the adsorptive separation. The effectiveness of NaCl for the removal of boron in TCS purification is also described in comparison with other well-known adsorbents.

• The Korean Journal of Food And Nutrition
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• v.35 no.3
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• pp.213-222
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• 2022

Sprouts have various health benefits. Specifically, wheat sprouts are rich in bioactive compounds, such as vitamins and polyphenols. Elicitation induces and enhances secondary metabolite biosynthesis in plants. Therefore, in this study, we investigated the effects of sodium chloride (NaCl) treatments on the growth profile, free amino acid content, and antioxidant activity of germinated wheat (Triticum aestivum). Wheat seeds were germinated at 20℃ for 10 days and treated with 0, 2, 4, 7.5, and 10 mM of NaCl 10 days before harvesting. Treating the soil bed with NaCl increased the nutritional component amounts, such as free amino acids and γ-aminobutyric acid. The chlorophyll a and b concentrations were the highest in the hydroponic system treated with 7.5 mM NaCl. In addition, the polyphenol and flavonoid contents of sprouts treated with 2 and 7.5 mM NaCl were 1.94 and 1.34 times higher than that of the control sprouts (0 mM NaCl, water only), respectively. These results suggest that 2 to 4 mM NaCl treatments improve the nutritional and food quality of wheat sprouts more than water only.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.345-349
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• 2009

This study measured the amounts of uronic acid, total sugars, non-cellulosic neutral sugars, phenolic compounds as well as antioxidants activity in cell wall materials (CWM) derived from different parts of deodeok (Codonopsis lanceolata). The values of the uronic acid (UA): neutral sugars (NS) ratio in polymers extracted from the CWM of the flesh and skin were 4 and 6, respectively. The total sugar contents of the flesh and skin were 788.6 and 824.9 ${mu}g/mg$ of CWM, respectively. Galactose and arabinose were the main noncellulosic neutral sugars. The chemical structure of five phenolic compounds from the CWM were analyzed and identified as vanillic acid, p-OH-benzaldehyde, vanillin, ferulic acid, and 8-O-4' diferulic acid by HPLC spectral data. Among them, p-OH-benzaldehyde, vanillin, and 8-O-4' diferulic acid were the first compounds identified from the deodeok. The content of 8-O-4' diferulic acid in the skin CWM was 56.1 ${mu}g/g$ AIR (alcohol insoluble residue). The ethanol-NaOH fractions from CWM had the highest oxygen radical absorbance capacity (ORAC) activities, followed by the AIR fractions and ethanol fractions.

• Bulletin of the Korean Chemical Society
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• v.8 no.1
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• pp.6-9
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• 1987

The study of the $Na_3YSi_3O_9$ structure, by x-ray diffraction and infrared spectrum, showed that $Na_3YSi_3O_9$ is similar to $Na_4CaSi_3O_9$ except for its being pseudo-cubic instead of cubic. The peaks in the x-ray diffraction pattern of $Na_3YSi_3O_9$ could therefore be indexed on the basis of the $Na_4CaSi_3O_9$ cell. Also, modified $Na_3MSi_3O_9$ (M = Lu, Yb, Tm, Er, Y, Ho, Dy, Gd, Eu, and Sm) type compounds were synthesized by introducing excess sodium, decreasing M(III) concentration, and substituting small amount of phosphorus for silicon. The unit cell parameters of the composition $Na_{3.2}M_{0.7}Si_{2.9}P_{0.1}O_{8.7}$ were estimated from x-ray powder diffraction patterns using the Cohen method.