• International Journal of Industrial Entomology and Biomaterials
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• 제12권1호
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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.

• 한국축산식품학회지
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• 제38권6호
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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.

• 한국식생활문화학회지
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• 제22권1호
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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.

• 한국축산식품학회지
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• 제34권3호
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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.

• 방사성폐기물학회지
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• 제2권4호
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• pp.239-244
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• 2004

사용후핵연료 금속전환체의 저장 안정성을 높이기 위해 금속전환체의 주성분인 금속우라늄과 산화 안정화물질로 알려져 있는 Nb을 첨가하여 모의 금속전환체 합금을 제작하였다. 모의 금속전환체 합금을 $200{\sim}300^{\circ}C$ 온도구간에서 순수 산소분위기로 산화시험을 수행하고 무게증가(wt%)를 열중량 분석기(TGA)로 측정하였다. 산화 실험결과 U-Nb 모의 금속전환체는 순수 금속우라늄에 비하여 상당한 산화 저항성을 가졌다. U-Nb 합금의 경우 Nb의 함량 1, 2, 3, 4 wt%에 따라 각각 온도가 $200^{\circ}C$일 경우에는 1.61, 7.78, 11.76, 20.14배 , $250^{\circ}C$에서 1.45, 5.98, 10.08, 11.15배, $300^{\circ}C$에서 1.33, 4.82, 8.87, 6.84배 순수 금속우라늄에 비해 산화저항성이 향상되는 것으로 나타났다. 또한 U-1~4 wt%Nb 합금에 대한 활성화에너지는 17.13~21.92 kcal/mol 로 나타났다.

• 자원리싸이클링
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• 제29권5호
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• pp.64-72
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• 2020

시멘트 산업의 질소산화물 배출량 감축을 위해 소성로에 다단연소공정을 적용할 경우, 질소산화물을 질소로 환원시키고 미연소 물질을 완전히 연소시켜 연소효율을 증대할 수 있는 산화/환원 구간이 필수적이다. 이에 본 연구에서는 시멘트 소성로 calciner에 산화/환원 구간 설정 시 최종 생산품인 시멘트 클링커의 품질안정성을 확보할 수 있는 최적 산화/환원 소성분위기를 거시적으로 관찰하고자 하였으며, 소성조건에 따른 원료물질의 질량변화, 탈탄산률, 소성완료율 등을 조사하였다. 실험결과, 대체로 환원분위기보다 산화분위기에서 원료물질의 열분해가 촉진되는 경향을 나타내며, 원료물질 자체 성분특성에 따라 비교적 CaO 함량이 높은 석회석의 열분해가 시멘트 조합원료보다 늦게 진행되는 것을 알 수 있었는데 이는 소성로 내 CO₂ 분압에 의한 현상으로 생각된다. 산화/환원 소성분위기에 따른 원료물질의 열분해 특성은 일반적인 석회석 열분해 온도보다 낮은 온도범위에서 비교적 큰 차이를 보였는데, 소성온도 750℃ 구간에 산화분위기 형성에 따라 원료물질의 열효율 향상을 기대할 수 있을 것으로 생각된다. 다만, 본 연구의 경우 실험실 규모의 연구로서 현장공정과는 차이가 있기 때문에, pilot plant 규모의 실검증결과가 필요한 것으로 판단된다.

• 한국염색가공학회지
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• 제13권5호
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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.

• 한국염색가공학회지
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• 제13권5호
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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.

• 한국식품조리과학회지
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• 제28권2호
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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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• 제33권8호
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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.