• International Journal of Industrial Entomology and Biomaterials
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• v.12 no.1
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• pp.1-5
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• 2006

Cordyceps, one of the well-known traditional Chinese medicines, consists of the dried fungus C. sinensis growing on the larva of caterpillar. It is commonly used as a tonic of restoring vital body functions. In order to evaluate the pharmacological effects of C. militaris, the anti-oxidation and antiaging effect of cultured C. militaris growing on pupa of silkworm Bombyx mori, were investigated. The results showed! that the contents of lipofusin in myocardium were reduced and the SOD activity in the liver were elevated in a dose-dependent manner while no effect was observed for blood GSH-Px activity and liver MDA content in mice perfused with the cultured C. militaris compared to those untreated mice. Furthermore, the average life span, maximum life span and 50% death time of the fruit flies treated with cultured C. militaris were markedly prolonged. The results suggest that the cultured C. militaris growing on pupa of silkworm possesses anti-oxidation and delay senescence activity.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1196-1202
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• 2018

The objective of this study was to determine the antioxidant activity of gamma-irradiated Asparagus cochinchinensis (Asparagi radix) (Lour.) Merr. Extract (ARE) and its inhibition effect on food lipid oxidation using emulsion-type pork sausage as a model. ARE was prepared from dried Asparagi radix root and ARE solution (1.0 g/mL) was gamma-irradiated with designated doses at 5, 10, and 20 kGy. Antioxidant activity of ARE solution was determined by measuring 1,1-diphenyl-e-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-9-sulphonic acid) (ABTS) radicals. Activities of DPPH and ABTS radicals were decreased, whereas total phenolic contents increased after gamma irradiation with a dose dependence. Addition of gamma-irradiated ARE dose-dependently retarded lipid oxidation of emulsion-type pork sausage during storage at $4^{\circ}C$. These results indicated that gamma-irradiated ARE might have antioxidant activity more than non-irradiated ARE due to increase of the content of polyphenolic compounds by ionizing radiation.

• Journal of the Korean Society of Food Culture
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• v.22 no.1
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• pp.83-90
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• 2007

The changes of the color, texture and volatile flavor compounds of Yu-gwa were investigated that affected by the oxidation during storage to characteristic Yu-gwa quality. Among the proximate compositions, carbohydrate was the most abundant component, and followed by lipid and moisture. Although the change of the color showed different pattern by the packaging materials during the storage period, the value of yellowness(b) increased but that of lightness(L) decreased dramatically after 3 month storage. In the textural properties reported closely related with the moisture content, hardness was fairly affected on the period of the storage rather than the type of packaging materials. The flavor compounds of Yu-gwa were analyzed to evaluate the change of distinct volatile compounds during storage. Of the twenty one separated volatile compounds, major volatiles were aldehydes, alcohols and alkenes. The results also showed that polyethylene(PE) contained less volatiles than polypropylene(PP) by the oxidation process during storage.2,4-Decadienal was gradually increased with the period of the storage, whereas octane and furan were decreased. The results provided that the change of the flavor distribution during the storage, and also the possibility of the volatiles such as hexanal, nonanal and 2,4-decadienal as the indicator for the oxidation process.

• Food Science of Animal Resources
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• v.34 no.3
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• pp.273-279
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• 2014

The objective of this study was to investigate the effects of the packaging method on the lipid and protein oxidation, and color in aged top round from Hanwoo (Korean native cattle) for 14 d at $4^{\circ}C$. Catalase activity was the highest (p<0.05) in vacuum packaging (VP) treatment during storage, and was higher (p<0.05) in 50% Ox-MAP and 50% Ox-MAP+vacuum skin packaging (VSP) treatments than in other treatments at d 14. Superoxide dismutase activity was higher (p<0.05) in VP, 50% Ox-MAP, and 50% Ox-MAP+VSP treatments than in other treatments at d 14. During storage, total antioxidant activity was the highest (p<0.05) in VP treatment and was higher (p<0.05) in 50% Ox-MAP+VSP treatment than in 80% Ox-MAP treatment. TBARS value was the lowest (p<0.05) in VP treatment during storage and was lower (p<0.05) in 50% Ox-MAP and Ox-MAP+VSP treatments than in 80% Ox-MAP and Ox-MAP treatments, respectively. Carbonyl content was the lowest (p<0.05) in VP treatment from 10 d. From 7 d, the $a^*$ value was the highest (p<0.05) in VP treatment and was higher (p<0.05) in 50% Ox-MAP and 50% Ox-MAP+VSP treatments than in other treatments. The $b^*$ value was the highest (p<0.05) in VP treatment from 3 d, and was higher (p<0.05) in 80% Ox-MAP+VSP, 50% Ox-MAP, and 50% Ox-MAP+ VSP treatments than in 80% Ox-MAP treatment at d 14. Therefore, VP improved the oxidation and red color stabilities in stored-aged top round compared with Ox-MAP. In addition, 50% Ox-MAP improved the lipid oxidation and red color stabilities compared with 80% Ox-MAP, and its inhibitory effect on lipid oxidation was enhanced by combination with VSP.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.4
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• pp.239-244
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• 2004

In order to enhance an oxidation resistance of the pure uranium metal under air condition, a small quantity of niobium(Nb) which is known to mitigate metal oxidation is added into uranium metal as an alloying element. A simulated metallic uranium alloy, U-Nb has been fabricated and then oxidized in the range of 200 to $300^{\circ}C$ under the environment of the pure oxygen gas. The oxidized quantity in terms of the weight gain(wt%) has been measured with the help of a thermogravimetric analyzer. The results show that the oxidation resistance of the U-Nb alloy is considerably enhanced in comparison with that of the pure uranium metal. It is revealed that the oxidation resistance of the former with the niobium content of 1, 2, 3, and 4 wt% is : 1) 1.61, 7.78, 11.76 and 20.14 times at the temperature of $200^{\circ}C$ ; 2) 1.45, 5.98, 10.08 and 11.15 times at $250^{\circ}C$ ; and 3) 1.33, 4.82, 8.87 and 6.84 times at $300^{\circ}C$ higher than that of the latter, respectively. Besides, it is shown that the activation energy attributable to the oxidation is 17.13~21.92 kcal/mol.

• Resources Recycling
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• v.29 no.5
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• pp.64-72
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• 2020

When the multi-stage combustion process is applied to the cement kiln to reduce nitrogen oxide emissions in the cement industry, oxidation/reduction section that can increase combustion efficiency by reducing NO_x to NO and completely burning unburned materials is essential In this study, when applied the oxidation/reduction system of the cement kiln preheater and calciner, the optimal oxidation/reduction calcination crisis that can secure the quality stability of the final product, cement clinker, was to be observed macroscopically, and the mass change of raw materials according to the burning conditions, decarbonation rate, and calcination rate were investigated. The results showed that the thermal decomposition of raw materials tends to be promoted in the oxidation condition rather than in the reduction condition, and that the thermal decomposition of limestone, which has a relatively high CaO content, is carried out later than that of cement raw meal, which is thought to be caused by the CO₂ fractionation in the kiln. The thermal decomposition properties of raw materials according to oxidation/reducing burning condition showed a relatively large difference in temperature range lower than normal limestone themal decomposition temperature, which is thought to be expected to improve the thermal efficiency of raw materials according to the formation of oxidation condition in the section 750℃ of burning temperature. However, for this study, lab scale. Because there is a difference from the field process as a scale study, it is deemed necessary to verify the actual test results of the pilot scale.

• Textile Coloration and Finishing
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• v.13 no.5
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• pp.1-1
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• 2001

As the basic study to investigate the mechanism of improvement in the dyeing fastness of natural dyes on silk fabrics the optical behavior of tannin solution, the optimal condition of tannin treatment and the changes of the physical structure of silk fabrics were studied in the treatment of tannin. Results obtained were as follows ; 1.The K/S values of tannin-treated silk fabrics were not changed by tannin content on silk fabrics but yellowing of tannin in treatment condition. 2. As the concentration of tannin was increased in its treating condition, the tannin content and K/S vague of tannin-treated silk fabrics were increased. 3. Because tannin gave rise to yellowing by hydrolysis and oxidation at high temperature, the higher tannin-treating temperature was, the lower the tannin content and K/S values of silk fabrics 4. The tannin content of silk fabric was higher in acidic treating condition and the highest K/S value was showed at pH 5. 5. As the tannin content of silk fabric was increased, the value of ζ -potential of it became negative. 6. As the tannin content of silk fabric was increased, the crystallinity and crystallite size of it were decreased. This meant that the fraction of amorphous region in the fibers increased. And the degree of orientation of it was decreased with the tannin treatment.

• Textile Coloration and Finishing
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• v.13 no.5
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• pp.289-297
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• 2001

As the basic study to investigate the mechanism of improvement in the dyeing fastness of natural dyes on silk fabrics the optical behavior of tannin solution, the optimal condition of tannin treatment and the changes of the physical structure of silk fabrics were studied in the treatment of tannin. Results obtained were as follows ; 1 The K/S values of tannin-treated silk fabrics were not changed by tannin content on silk fabrics but yellowing of tannin in treatment condition. 2. As the concentration of tannin was increased in its treating condition, the tannin content and K/S vague of tannin-treated silk fabrics were increased. 3. Because tannin gave rise to yellowing by hydrolysis and oxidation at high temperature, the higher tannin-treating temperature was, the lower the tannin content and K/S values of silk fabrics 4. The tannin content of silk fabric was higher in acidic treating condition and the highest K/S value was showed at pH 5. 5. As the tannin content of silk fabric was increased, the value of $\xi$ -potential of it became negative. 6. As the tannin content of silk fabric was increased, the crystallinity and crystallite size of it were decreased. This meant that the fraction of amorphous region in the fibers increased. And the degree of orientation of it was decreased with the tannin treatment.

• Korean journal of food and cookery science
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• v.28 no.2
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• pp.123-131
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• 2012

This study was carried out for the purpose of inquiring into the effects on shelf-life, quality characteristics and antioxidative activities of Majakgwa with regard to the use turmeric powder at varying concentrations in the recipe. Chemical composition analysis showed that the contents of crude fat, crude protein and carbohydrates are high in turmeric powder. With an increase of the amount of turmeric powder used in Majakgwa recipes, dough pH was higher than that of the control group. Antioxidative activities were the highest in the groups with 3% and 9% turmeric powder content, and the value increased largely after 12 days of storage. Excellent antioxidative activities were observed in the 6% turmeric content group. For recipes with turmeric contents of more than 15%, oxidation was accelerated from early on in storage. The hardness, brittleness and bitterness increased significantly with the increase of the turmeric content. The intensity, chromaticity, crunch and intensity of the surface colors, all increased significantly with the increase of turmeric content. The general preference ratings for Majakgwa with added turmeric was highest for the 9% content recipe. Over all Majakgwa recipes with 6~9% turmeric powder content were found to ideal.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2494-2498
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• 2012

Preparation of several new spirocyclic mercapto derivatives is described. Thiol protection on multi-carbonyl compounds allows of high sulfur content necessary to induce high refractive index. Condensation of 1,3-dimercapto-2-propanol and cyclohexanone followed by successive oxidation and thioacetalization affords a dispirocycle with four sulfurs. Selective S,S-protection of cyclohexane-1,4-dione is achieved with 1,3-dimercapto-2-propanol and 2,3-dimercapto-1-propanol to provide dispirocycles with four sulfurs. Olefine-oxidation of norbornene gives a useful dialdehyde intermediate which is transformed to 1,3-dithiolane for a linearly-bound-cyclic molecule. Refractive index of linearly-bound-cycles was below 1.60 and dispirocycles exhibited high refractive index of 1.57-1.69.