• Nuclear Engineering and Technology
• /
• v.41 no.3
• /
• pp.319-326
• /
• 2009

This study was carried out to investigate the high-acidity co-separation of Am and RE from a simulated radwaste solution by a solvent extraction using a mixture of Dimethyldibutyltetradecylmalonamide (DMDBTDMA, as an extractant) and dihexyl octanamide (DHOA, as a phase modifier) diluted with n-dodecane (NDD). All the experiments were conducted as a batch type. First, the environmentally friendly DMDBTDMA and DHOA composed of only CHON atoms were self-synthesized. Then, the conditions for the prevention of a third phase, generated in the organic phase were examined. In addition, the effects of the concentration of nitric acid, DHOA, oxalic acid and $H_2O_2$ on the co-extraction of Am and RE were elucidated. Consequently, the optimum condition of (0.5M DMDBTDMA+0.5M DHOA)/NDD-0.3M $C_2H_2O_4-4.5M$ $HNO_3$ and O/A=2 was obtained through experimental work. Under this condition, the extraction yields were found to be about 80% for Am, more than 70% for RE such as La, Eu, Nd, Ce, etc., 3% for Cs and Sr, 69% for Fe and less than 11% for Mo and Ru. For the co-extraction of Am and RE, Fe should be removed in advance or prevented from a co-extraction with Am by controlling the different extraction rates of Am and Fe. About 95% of the Am and RE in the organic phase were stripped using a 0.5M $HNO_3$.

• Bulletin of the Korean Chemical Society
• /
• v.13 no.5
• /
• pp.531-537
• /
• 1992

The approximate rates and stoichiometry of the reaction of excess potassium 2-thexyl-1,3,2-dioxaborinane hydride(KTDBNH) with 55 selected compounds containing representative functional groups under standardized conditions (tetrahydrofuran, TEX>$0^{\circ}C$, reagent : compound=4 : 1) was examined in order to define the characteristics of the reagent for selective reductions. Benzyl alcohol and phenol evolve hydrogen immediately. However, primary, secondary and tertiary alcohols evolve hydrogen slowly, and the rate of hydrogen evolution is in order of $1^{\circ}$> $2^{\circ}$> $3^{\circ}$. n-Hexylamine is inert toward the reagent, whereas the thiols examined evolve hydrogen rapidly. Aldehydes and ketones are reduced rapidly and quantitatively to give the corresponding alcohols. Cinnamaldehyde is rapidly reduced to cinnamyl alcohol, and further reduction is slow under these conditions. The reaction with p-benzoquinone dose not show a clean reduction, but anthraquinone is cleanly reduced to 9,10-dihydro-9,10-anthracenediol. Carboxylic acids liberate hydrogen immediately, further reduction is very slow. Cyclic anhydrides slowly consume 2 equiv of hydride, corresponding to reduction to the caboxylic acid and alcohol stages. Acid chlorides, esters, and lactones are rapidly and quantitatively reduced to the corresponding carbinols. Epoxides consume 1 equiv hydride slowly. Primary amides evolve 1 equiv of hydrogen readily, but further reduction is slow. Tertiary amides are also reduced slowly. Both aliphatic and aromatic nitriles consume 1 equiv of hydride rapidly, but further hydride uptake is slow. Analysis of the reaction mixture with 2,4-dinitrophenylhydrazine yields 64% of caproaldehyde and 87% of benzaldehyde, respectively. 1-Nitropropane utilizes 2 equiv of hydride, one for hydrogen evolution and the other for reduction. Other nitrogen compounds examined are also reduced slowly. Cyclohexanone oxime undergoes slow reduction to N-cyclohexylhydroxyamine. Pyridine ring is slowly attacked. Disulfides examined are reduced readily to the correponding thiols with rapid evolution of 1 equiv hydrogen. Dimethyl sulfoxide is reduced slowly to dimethyl sulfide, whereas the reduction of diphenyl sulfone is very slow. Sulfonic acids only liberate hydrogen quantitatively without any reduction. Finally, cyclohexyl tosylate is inert to this reagent. Consequently, potassium 2-thexyl-1,3,2-dioxaborinane hydride, a monoalkyldialkoxyborohydride, shows a unique reducing characteristics. The reducing power of this reagent exists somewhere between trialkylborohydrides and trialkoxyborohydride. Therefore, the reagent should find a useful application in organic synthesis, especially in the field of selective reduction.

• Journal of the East Asian Society of Dietary Life
• /
• v.20 no.6
• /
• pp.896-902
• /
• 2010

Omija contains high organic acid content (5~7%) that must be reduced in order to produce high quality wine for consumption. In this study, we used pear, which has low total acid but plenty of sugar, to relieve the sourness of Omija material. Our group mixed Omija and pear at a ratio of 1:9 to 1:15 in order to attain a 0.5~0.7% total acid level, similar to commercial wine. As Omija was mixed with pear, the red color of Omija changed to a lighter red color. Alcohol fermentation solution of Bokbunja and Gaeryangmeoru were used to make up for the light red color of Omija pear wine. The red color of Bokbunja was confirmed to be similar to the original red color of Omija. It was proven that addition of 3~5% Bokbunja to Omija pear mixture wine produced replicated the red color image of Omija. Our results show that addition of 2~5% xylitol to Omija pear mixture wine was good by sensory test.

• Journal of Life Science
• /
• v.27 no.12
• /
• pp.1430-1436
• /
• 2017

This study assessed the effects of treatment with sap extract from onion residues postharvest and purslane on the quality and quantity of organic onions. At the bending stage, onions treated with the sap extract showed vigorous growth, with higher plant heights, more leaves, and longer sheath lengths than untreated onions. The onion yield was significantly increased when the plant was treated with extracted sap as compared with that of untreated plants (p<0.05). The bulb weight distribution of onions in the mixed onion and purslane treatment was also significantly increased (~300 g) as compared with that of the other treatment (p<0.05). Except for CaO and S, the mineral content of the onions produced from plants treated with the onion and purslane extract mixture was higher than those of onions in the other treatment. The hardness of onions produced from plants treated with the onion and purslane extract was significantly increased (8% and 20%, respectively) as compared with that of onions produced from plants treated with the onion extract only or no treatment (p<0.05). However, there was no significant difference in the sugar contents of the onions produced from extract-treated and nonextract-treated plants. Postharvest, the content of inorganic components (phosphate, calcium, sulfuric acid, and manganese) was higher in soil treated with the onion extract than in soil treated with the onion and purslane extract and non-treated soil. It can be concluded that residues left after onion harvests and purslane extract can be used as natural and environmentally friendly materials for the cultivation of organic onions.

• Korean Journal of Food Science and Technology
• /
• v.25 no.6
• /
• pp.666-671
• /
• 1993

Mixtures (total solid content: 15%) prepared with whole milk added with skim milk powder and/or sweet potato and/or pumpkin were fermented with 0.205% gelatin, 2% sugar and yogurt bacteria. The fermented mixtures (curd yogurt) were evaluated for acid production (pH, titratable acidity), number of viable cell, sensory property and keeping quality. The acid production of all mixtures remarkably increased for the first 12 hours and there is no significant difference among the mixtures. The lactic acid bacteria counts in the all products after 24 hours incubation were above $6.4{\times}10^{9}cfu/ml$. In organic acids, the mixture added with skim milk powder was higher ratio of lactic acid content to total acidity than those added with sweet potato and/or pumpkin. The sensory score of mixture containing sweet potato was best but curd yogurt containing pumpkin reduced the sensory property. When each mixtures were kept at $5^{\circ}C$ for 15 days, pH, titratable acidity, and number of viable tells of yogurt were not changed.

• Food Science and Preservation
• /
• v.30 no.3
• /
• pp.514-525
• /
• 2023

New types of vinegar drinks are being processed and developed using various raw materials. In this study, a beverage containing a mixture of 0.25% red ginseng extract and 5% Prunus mume fruit vinegar (RPV) was evaluated for its anti-fatigue effect on high-intensity exercised rats. RPV administration markedly enhanced running endurance and significantly decreased fatigue-related serum biomarkers, such as inorganic phosphate, ammonia, and L-lactate, compared to the other groups. In addition, RPV administration increased glycogen contents in the liver and muscles and decreased creatine kinase activity in the serum and muscles. RPV administration also remarkedly increased the activity of lactate in the muscles. Furthermore, HPLC analysis revealed that main organic acids in RPV were acetic acid, malic acid, and citric acids. Overall, the results indicate that RPV improved fatigue recovery in exhausted rats, thus proving a promising material of functional food to attenuate fatigue.

• Korean Chemical Engineering Research
• /
• v.54 no.6
• /
• pp.806-811
• /
• 2016

Organosolv pretreatment is the process to frationation of lignocellulosic feedstocks to enhancement of enzymatic hydrolysis. This process has advantages that organic solvents are always easy to recover by distillation and recycled for pretreatment. The chemical recovery in organosolv pretreatment can isolate lignin as a solid material and carbohydrates as fermentable sugars. For the economic considerations, using of low-molecular-weight alcohols such as ethanol and methanol have been favored. When acid catalysts are added in organic solvent, the rate of delignification could be increased. Mineral acids (hydrochloric acid, sulfuric acid, and phosphoric acid) are good catalysts to accelerate delignification and xylan degradation. In this study, the biomass was pretreated using 40~50 wt% ethanol at $170{\sim}180^{\circ}C$ during 20~60 min. As a results, the enzymatic digestibility of 2-stage pretreatment of rigida using 50 wt% ethanol at $180^{\circ}C$ was 40.6% but that of 1-stage pretreatment was 55.4% on same conditions, therefore it is shown that the pretreatment using mixture of the organosolv and catalyst was effective than using them separately.

• Culinary science and hospitality research
• /
• v.23 no.5
• /
• pp.25-33
• /
• 2017

This study was to investigate the effects of enzyme on quality characteristics and antioxidant activities of wild peach (Prunus persica L.) juice. pH levels and S.S (soluble solid) values in all samples ranged from 3.86 to 4.13 and from 48.0 to $55.0^{\circ}Brix$, respectively. The TA (total acidity) values of control (not treatment enzyme) were higher than those of the others. The highest 'L', 'a' and 'b' values were observed on PWP (preserved wild peach (Prunus persica L.) juice of cellulase/pectinase (1:1, w/w) sample. Glucose (26.65 g/100 g) and fructose (17.42 g/100 g) in PWP product were determined, however sucrose and maltose were not detected. The predominating organic acid components analyzed in PWP sample were tartaric (32.36 g/100 g) and lactc acids (209.34 g/100 g), whereas citric acid, acetic acid and malic acid were not detected. Higher scores for taste, flavor, color and overall acceptance were found for PWP products compared to other samples. The total phenolic content (13.31 mg GAE/mg dry weight) analyzed using Folin-Ciocalteu's reagent, of PWP sample was higher than those of the others and the total flavonoid concentrations were also 10.95 mg CE/mg dry weight. The DPPH radical scavenging and ABTS radical scavenging activities in all samples ranged from 55.16 to 74.29% and from 39.59 to 82.79%, respectively. The antioxidant activities were affected by addition of enzyme. These results indicate that the use of the mixture of cellulase and pectinase could increase the quality, and antioxidant potentials of sugar preserved wild peach (Prunus persica L.) juice by enzymatic treatment.

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.8
• /
• pp.1273-1283
• /
• 2020

Objective: This study investigated a method of preparing corn stover for Irpex lacteus (I. lacteus) treatment to improve its in vitro rumen degradability under non-sterile conditions. Methods: Corn stover was inoculated with Lactobacillus plantarum (L. plantarum), Lactobacillus buchneri (L. buchneri), and an equal mixture of these strains, and ensiled for 0, 3, 7, 14, and 28 days. After each period, a portion of the silage was sampled to assess the silage quality, and another portion of the silage was further treated with I. lacteus at 28℃ for 28 d. All the samples were analyzed for fermentation quality, chemical composition, and in vitro gas production (IVGP) as a measure of rumen fermentation capacity. Results: Lactic acid bacteria (LAB) was found to improve the silage quality of the corn stover, and the corn stover silage inoculated with L. plantarum produced more lactic acid and higher IVGP than other silage groups. The I. lacteus colonies flourished in the early stage of corn stover silage, especially on the 3-d corn stover silage inoculated with both L. plantarum and L. buchneri. This led to an 18% decrease in the acid detergent lignin content, and a 49.6% increase in IVGP compared with the raw stover. Conclusion: The combination of ensiling with the mixed LAB inoculation and I. lacteus treatment provided a cost-effective method for the improvement of the IVGP of corn stover from 164.8 mL/g organic matter (OM) to 246.6 mL/g OM.

• The Korean Journal of Food And Nutrition
• /
• v.30 no.4
• /
• pp.813-822
• /
• 2017

To investigate the aroma and quality characteristics of wine bestowed by the degree of ripening of Cheongporang grapes, the general quality composition, color, organic acid, physiological activity, aroma component and sensory evaluation were analyzed. The general characteristics of the wine assessed were pH 3.34~3.50, total acidity 0.46~0.67%, color intensity 0.074~0.116, lightness 98.99~99.74, redness -0.39~0.01, and yellowness was 1.52~3.10. Malolactic fermentation was not relative to the contents of malic acid and lactic acid. The total polyphenol content and antioxidant activity were lowest in C3 wines made with ripe grapes and highest in C4 wines made with mixed grapes. Aroma analysis identified 6 alcohols, 15 esters and 5 miscellaneous compounds. Compounds with higher odor activity value (OAV) were 3-methyl-1-butanol, ethyl butanoate, isopentyl acetate, ethyl hexanoate, ethyl octanoate, ethyl decanoate and octanoic acid. The C4 wine, a mixture of grapes with different degrees of ripening, had the highest ester content and ratio. The lowest values were found in the C3 wine made with ripe grapes. Results of the sensory evaluation related the C4 wine, containing a large amount of ester compounds having high OAV values as the aroma component, as the best and most preferred wine.