• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.3
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• pp.55-64
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• 2023

This batch experiment was conducted to investigate the patterns of major plant nutrients in the leachates from the soil that was incorporated with rice hull biochar adjusted pH with dry fish powder utilizing rice hull biochar for loading the soil microorganisms. The rice hull biochar adjusted pH between 6.0 and 7.0, and the mixture ratio of rice hull biochar and dry fish powder was 4:6. The treatments consisted of three; the soil incorporated with rice hull biochar non-adjusted pH with dry fish powder as control (RB + DF), the soil incorporated with rice hull biochar adjusted pH by pyroligneous acid solution and dry fish powder (RBP+DF), and the soil incorporated with rice hull biochar adjusted pH by citric acid solution and dry fish powder (RBC+DF). NH₄-N, NO₃-N, PO₄-P, and K concentrations in the leachates were analyzed during incubation. The accumulated NH₄-N and PO₄-P concentrations in the leachates from the RBC+DF treatment were the highest during leaching periods. The highest accumulated NO₃-N and K concentrations in the leachates from the RBP+DF treatment were observed. It observed that NH₄-N and PO₄-P were more released in the adjusted citric acid solution, but NO₃-N and K were less released than those in the pyroligneous acid solution due to their low absorption capacity. Furthermore, it is necessary to investigate crop growth responses to the soil incorporated with adjusted pH rice hull biochar and dry fish powder for loading soil microorganisms.

• The Korean Journal of Community Living Science
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• v.22 no.4
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• pp.549-556
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• 2011

The objective of this study was to develop a food material and, examination of fermented juice using turnips. The highest yield of fermented juice was with the mixture ratio of 60% turnip, 20% rice-nuruk and 20% sugar. The total acidity and turbidity increased depending on the adding rate of rice-nuruk. By reducing sugar concentration by 24.9%, 22.6% and 25.3% resulted in samples containing 5%, 20% and 35% of rice-nuruk. The reduced sugar concentration was the highest at 35% rice-nuruk and 5% sugar. As a result of enzyme activity, ${\alpha}$-amylaze was the highest at 5% rice-nuruk and 35% sugar, and glucoamylase was increased by depending on the rice-nuruk concentration. The main organic acids in fermented turnip juice were succinic acid, acetic acid and lactic acid, and were increased during fermentation. DPPH free radical scavenging activity of fermented turnip juice was higher than that of non fermented turnip juice. Also, the nitrite scavenging ability was the highest($89.58{\pm}0.00$) in 35% rice-nuruk at pH 3.0.

• Bulletin of the Korean Chemical Society
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• v.8 no.4
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• pp.285-291
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• 1987

The approximate rates, stoichiometries and products of the reaction of potassium triethylborohydride $(KEt_3BH)$ with selected organic compounds containing representative functional groups under the standard condition $(0^{\circ}C,$ THF) were examined in order to explore the reducing characteristics of this reagent as a selective reducing agent. Primary alcohols, phenols and thiols evolve hydrogen rapidly whereas secondary and tertiary alcohols evolve very slowly. n-Hexylamine is inert to this reagent. Aldehydes and ketones are reduced rapidly and quantitatively to the corresponding alcohols. Reduction of noncamphor gives 3% exo- and 97% endo-norboneol. Anthraquinone is cleanly reduced to 9,10-dihydro-9,10-dihydroxyanthracene stage. Carboxylic acids liberate hydrogen rapidly and quantitatively but further reduction does not occur. Anhydrides utilize 2 equiv of hydride to give an equimolar mixture of acid and alcohol. Acid chlorides, esters and lactones are rapidly and quantitatively reduced to the corresponding alcohols. Epoxides are reduced at moderate rates with Markovnikov ring opening to give the more substituted alcohols. Primary amides liberate 1 equiv of hydrogen rapidly. Further reduction of caproamide is slow whereas benzamide is not reduced. Tertiary amides are reduced slowly. Benzonitrile utilizes 2 equiv of hydride in 3 h to go to the amine stage whereas capronitrile takes only 1 equiv. The reaction of nitro compounds undergo rapidly whereas azobenzene and azoxybenzene are reduced slowly. Cyclohexanone oxime rapidly evolves hydrogen without reduction. Phenyl isocyanate utilizes 1 equiv of hydride to proceed to formanilide stage. Pyridine N-oxide and pyridine is reduced rapidly. Disulfides are rapidly reduced to the thiol stage whereas sulfoxide, sulfonic acid are practically inert to this reagent. Sulfones and cyclohexyl tosylate are slowly reduced. Octyl bromide is reduced rapidly but octyl chloride and cyclohexyl bromide are reduced slowly.

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.629-646
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• 2013

This study was conducted to investigate effects of terpenoids-rich plant extracts (TRPE) on the in vitro ruminal fermentation characteristics and methane production. The ruminal fluid was collected from a cannulated Hanwoo cow fed concentrate and timothy in the ratio of 6 to 4. The TRPE as Mint (Mentha arvensis var. piperascens), Pine (Pinus densiflora), Japan cedar (Cryptomeria japonica), Sichuan pepper (Zanthoxylum piperitum), Hinoki cypress (Chamaecyparis obtuse) and Japanese black pine (Pinus thunbergii) were used in this study. The 15 mL of mixture, contains McDougall buffer and rumen fluid in the ratio of 2 to 1. The mixture was dispensed anaerobically 50 mL serum bottles and it is contained 0.3 g timothy substrate and 5% TRPE. The bottles were incubated at $39^{\circ}C$ for 3, 6, 9, 12, 24, 48 and 72 hours. The pH value decrease by increased incubation times and the pH values at all times were significantly (p<0.05) higher in treatments than in control. The digestibility of dry matter at 3 hours was significantly (p<0.05) higher in mint treatment than in control. Productions of total gas and carbon dioxide at before 12 hours was significantly lower (p<0.05) in treatments than in control. The methane production at 24 hours was significantly (p<0.05) lower in treatments than in control. The concentrations of acetic acid and propionic acid at 24 hours were significantly higher (p<0.05) in mint and pine treatments than in control. In conclusion, the terpenoid-rich plant extracts were shown to decreased methane emission and without adversely affected ruminal fermentation. Therefore, the terpenoid-rich plant extracts as mint and pine were shown to decreased methane production and it has potential possibility for ruminal fermentations.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.386-395
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• 2016

To develop a functional fermentation food from Rubus coreanus Miquel (Bokbunja) and chlorella mixtures, optimal lactic acid fermentation conditions were established, and quality properties based on physicochemical evaluation such as chemical compositions, free sugars, organic acids, and antibacterial activities were investigated. Regarding optimal fermentation strain selection, formation of lactic acid was best in Lactobacillus plantarum among the experimental strains (10 kinds), and the optimal fermentation temperature was $37^{\circ}C$. In addition, overall acceptability in the sensory evaluation was highest in the 5% chlorella mixture sample. Therefore, quality properties of the prepared sample under the established optimal fermentation conditions were investigated. Moisture, total sugar (dry basis), crude fiber (dry basis), and pH of fermented Rubus coreanus Miquel juice (RCM) with 5% chlorella mixture (RCM-C5) were reduced by 4.90%, 14.15%, and 0.32%, respectively, as compared with non-fermented RCM. Meanwhile, crude protein, crude fat, and crude ash (dry basis) of RCM-C5 were elevated by 13.75%, 0.18%, and 0.73%, respectively, as compared with RCM. The yellowness (b value) of color values was greater in RCM-C5 compared to RCM. The free sugar and organic acid contents of RCM-C5 were elevated by 0.97% and 616.30 mg%, respectively, as compared with RCM. In addition, the gram positive bacterium Staphylococcus aureus was elevated by 5.83% while gram negative bacteria Escherichia coli and Salmonella Typhimurium were elevated by 2.94% and 4.67%, respectively, as compared with RCM. In conclusion, the quality properties of RCM and chlorella lactic acid fermentation mixtures were improved compared with the general RCM product. Consequently, it is possible to apply fermented RCM as a functional fermentation food.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.266-271
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• 1994

The curd yogurt (total solid content: 14%) was prepared from milk added with skim milk powder and potato puree. Potato puree comprised 9.5. 13,8 and 17.9% (dry basis) of the milk-potato mixture, and the effect of potato on the quality of yogurt was investigated. Addition of potato remarkably stimulated acid production and propagation of lactic acid bacteria, and viable cells reached above $3.9{\times}10^{10}$ CFU/ml after 12 hours. As potato content increased, the ratio of lactic acid content to total acidity decreased, while citric acid increased. The major organic acids of yogurt were lactic acid, citric acid, and acetic acid. Viscosity of yogurt was increased in proportion to the increment of the potato content. After 24 hours of incubation, the sensory score of yogurt containing 13.8% (dry basis) potato showed better sensory acceptability. When curd yogurt added with potato was kept at $5^{\circ}C$ for 15 day, its keeping quality was relatively good. Viable cells of lactic acid bacteria and ${\beta}-galactosidase$ activity decreased rapidly at pH 1.5, and 2.5, but the group added with potato was more stable than control.

• Food Science and Preservation
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• v.24 no.6
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• pp.827-833
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• 2017

This study was investigated the effects of various commercial sanitizers on microbial characteristics in fresh-cut iceberg lettuce during storage. For screening sanitizer, lettuce was cut and dipped in chlorine water ($0.2ml{\cdot}L^{-1}$), solution of organic acids such as ascorbic acid, citric acid, acetic acid, mixture of ascorbic acid and acetic acid (1-6%), and solutions of commercial sanitizers such as Formula 4$^{TM}$ (1,3,4%), Fresh produce wash$^{TM}$ (1,3,4%), Cleancol$^{TM}$ (1%), Chitochol$^{TM}$ (1%) and Natural Ca$^{TM}$ (0.1%) for 3 min, respectively. Washing lettuce with selected sanitizers resulted in reduction of aerobic bacteria of more than 2 log CFU/g. Initial pH of lettuce was related with the pH of sanitizers. pH ranged from 4.7 to 6.1 in Formula 4 (4%, pH 1.7) and Natural Ca (0.1%, pH 12.0), respectively. Chlorine water showed consistent and significant inhibition effect in all of microorganisms except total coliform. Over 3% of Formula 4 and Fresh produce wash were found to have high bactericidal activity among sanitizers. The sanitizers of chlorine water, Fresh produce wash, Chitochol and Natural Ca were effective in reducing yeast and mould populations. As coliform and E. coli, Formula 4 (4%) showed the highest bactericidal activity. The bactericidal effect of commercial sanitizers during storage varied with the kinds and concentrations of tested sanitizers. Although inhibition effect was not showed during storage, these results suggest that commercial sanitizers could be an alternative to chlorine for washing fresh-cut produce.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.1
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• pp.103-108
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• 2012

Nuruk is a fermented ingredient used for production of traditional Korean rice wine. In this study, quality characteristics of mixed-grain nuruk was made by brewing with different fungal strains was analyzed. Quality elements including enzyme activity and organic acids constituents were measured. The fermentation time of the nuruk did not make a significant difference in terms of its pH, but the acidity and amino acid content for nuruk made from a mixture of two fungal strains was higher than that seen with a single fungal strain. Overall, the enzyme activity for two fungal strain nuruk was higher than that observed for single fungal strain nuruk, with ${\alpha}$-amylase and acidic protease activity in the mixed strain nuruk observed to be more than twice that of the single strain. The major organic acids observed in the manufactured nuruk were identified as acetic, citric, formic, fumaric, lactic, malic and oxalic acids. The total amount of organic acids contained in the nuruk made with the two fungal strain was (2,116.3 mg%). The fungal strains used were A. kawachii SC60 nuruk (1,608.5 mg%) and A. oryzae RIB1353 nuruk (1,146.7 mg%).

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.482-488
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• 2001

Platinum group metals (pgm) are useful to many industries such as chemical, dental and medical, petroleum, refining, electrical and electronic, and automotive. Researchers at the South Dakota School of Mines and Technology and PGM Recovery Ltd. have developed jointly an environmentally sound and metallurgically efficient process for extracting these metals from secondary sources. Once these metals have been dissolved in the leach liquor, the individual metals mainly platinum, palladium, and rhodium, should be separated in order to recover the individual metals with high purity. During this investigation, solvent extraction has been chosen as the method used to achieve the separation and extraction of platinum, palladium, and rhodium from the leach liquor. There were three solutions used throughout this procedure: 1) Synthetic solution (200 ppm Pt 80 ppm Pd 20 ppm Rh; 300 ppm Pt, 180 ppm Pd 50 ppm Rh), and 2) Auto catalyst leach liquors (100 ppm Pt, 30 ppm Pd, 20 ppm Rh). The solvents investigated included Lix 84(2-hydroxy-5-nonylacetonphenone oxime in a mixture with 5-dodecylsalicyloxime), Lix 84-I, ACORGA CLX-50 (diester of pyridine 3,5 dicarboxylic acid), and di-hexyl sulfide. The extraction values achieved using ACORGA CLX-50, Lix 84, and Lix 84-I were respectively Pt (25%, 0% 0%), Pd (100%, 99.8%, 95.3%), and Rh (99.1%, 35.5%, 4.25%). The stripping processes for the Lix 84, and Lix 84-I were proven to be more involved than others. The solutions were required to be simultaneously heated and stirred. The percentages acquired through these processes yielded unsatisfactory results. The stripping procedure for the ACORGA CLX-50 was easier to execute, yet the percentage recovered from this process was also unsatisfactory. Overall the di-hexyl sulfide has proved to be the most successful organic for this procedure. The average percent extracted for palladium was excellent with 99.9% - 100% with very little Platinum and rhodium extracted. The ability of stripping palladium in ammonia solution was also found to be excellent.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.333-333
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• 2013

The poor conductivity of poly (3,4-ethylene dioxythiophene): poly (styrenesulfonate) (PEDOT:PSS) film hinders to use for a flexible electrode in solar cells. In this report we demonstrate that the conductivity of PEDOT:PSS film can be enhanced by modifying structures in a mixture of PEDOT: PSS aqueous solution and various organic solvents such as polar protic (2-propanol, methanol, ethanol, formic acid) and aprotic solvents (acetone and acetonitrile). To comparatively study the structural effects on the resulted electrical properties, the films are spin-coated on glasses and ITO. At the same time, a contact angle goniometer is used for clarifying a mechanism of wettability of PEDOT (hydrophobic) and PSS (hydrophilic) on the observed conductivity. The structures and electrical properties are investigated by FE-SEM (Field Emission Scanning Electron Microscopy), AFM (Atomic Force Microscopy), and 4-point probe, respectively.