• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2002년도 학술.기술논문발표회
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• pp.59-62
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• 2002

Recently, advanced system for water and wastewater treatment is introduced and operated because of water pollution and etc. One of this System makes use of O3(Ozone) for water and wastewater treatment. In airtight concrete structure, waterproofing phase as well as water are affected by strong oxidative O3 in the long-term. For this reason, material stability against O3 is examined. Consequently, the purpose of this study is to find out material stability an object of epoxy resin by way of accelerated O3 testing.

• Journal of Pharmaceutical Investigation
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• 제2권1호
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• pp.52-57
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• 1972

There are many reports on the stability of drugs in powders and various dosage forms. The author studied on the stability of ascorbic acid mixed with talcs. From the result of this experiment, it was considered that talcs markedly accelerated oxidative degredation of ascorbic acid in powders and the acceleration rate depends on the varieties of crude talcs. Iron salts seem to be the principal factor influencing the degradation of ascorbic acid Degradation rate of ascorbic acid mixed with purified talc is significantly slower than that with the crnde talcs. The more the concetration of ascorbic acid is diluted, the faster the degradation rate and degredation rate of Ascorbic acid is the function of tme.

• Preventive Nutrition and Food Science
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• 제9권1호
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• pp.1-6
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• 2004

Fresh ground beef was mixed with ascorbic acid, basil essential oil, majoram essential oil, or each essential oil combined with ascorbic acid and stored at 1 $\pm$ 1$^{\circ}C$ for 7 days. Color, lipid oxidation (TBARS formation), aerobic bacterial counts and pH were determined. Basil and majoram essential oils were effective in inhibiting color deterioration, lipid oxidation and bacterial growth. The combined addition of basil and ascorbic acid showed the highest protection against color fading, followed by majoram + ascorbic acid, and ascorbic acid alone. Basil and majoram essential oils were most effective in delaying TBARS formation (p < ().01). Ascorbic acid did not exert an antioxidative effect and even exhibited a pro-oxidant effect. The pH values of all samples increased slightly, but no significant differences were observed, either among treatments or throughout the storage time (p > 0.05).

• 기술사
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• 제31권5호
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• pp.110-120
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• 1998

The effect of heat treatment and the order of antioxidants treatment toward the thermally oxidized palm oil which has been stored at 60 $^{\circ}C$ was studied. The summerized results of this study are as follows; 1. In the accelerated autoxidation condition, tocopherol showed no distinct effect on the changes of peroxide of value between added tocopherol samples pre-and post treatment by heating. But, rosemary extract showed opposite result. It was supposed that rosemary extract had lower thermostability then tocopherol, because rosemary extract lost it's antioxidative activity during heating process. 2. The changes of acid value and anisidine value were more affected by heat treatment than the order of antioxidant treatment. 3. The oxidative stability measured by OSI showed same tendency as peroxide value. That is, the antioxidative activity of tocopherol in palm oil was more dependent on addition of antioxidants than heat treatment, but the rosemary extract had opposite character for antioxidative action in palm oil.

• Food Science and Biotechnology
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• 제18권1호
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• pp.185-189
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• 2009

Microencapsulation of flavor was carried out by molecular inclusion process using $\beta$-cyclodextrin (${\beta}CD$). ${\beta}CD$-flavor complex was prepared at various flavor-to-${\beta}CD$ ratios (1:6-1:12) to determine the effect of ${\beta}CD$ concentration on the inclusion efficiency. Maximum total oil retention and minimal surface oil content were obtained at flavors to ${\beta}CD$ ratio of 1:10. The physical properties and controlled release pattern of flavors from ${\beta}CD$-flavor complex were measured and compared with spray-dried microcapsules prepared using carbohydrate wall system. ${\beta}CD$-flavor complex showed higher total oil retention and surface oil contents, smaller mean particle size, lower moisture uptake, and higher oxidation stability than spray-dried microcapsule. Oxidative stability of flavor was correlated with hygroscopicity of wall materials. The controlled release mechanism was highly affected by temperature and characteristics of wall materials.

• 유변학
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• 제10권2호
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• pp.106-112
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• 1998

항공기용 소재로 개발된 에폭시/탄소섬유 복합재료가 매트릭스의 유리전이온도에 육 박하는 온도주기를 경험할 때 발생하는 복합재료의 구조 및 물성변화를 실험과 모델링을 통 하여 연구하였다. 복합재료의 표준 경화온도인 177$^{\circ}C$에서 2시간 체류시킨후 냉각시키는 바 복 열주기는 복합재료를 취약하게 하여 결국 표면에서부터 미세크랙이발생한다는 것을 알수 있었다. 이러한 열주기에 따른 미세크랙 현상은 매트릭스의 분해반응이 발생할수 있는 유효 표면적을 증가시키고 크랙을 통하여 산소의투과를 용이하게 함으로서 산화반응을 가속화하 여 복합재료시편의 무게감소를 가속화시키는 것으로 판단된다. 특히 본 연구에서는 등온과 등속도 승온조건을 주기적으로 반복하는 열주기 조건을 해석하기 위하여 열주기 조건을 특 정온도에서의 등오시간으로 전환할 수 있는 e-quivalent cycle time(ECT)를 제안하였고 이 를 이용하여 열주기에 의한 복합재료 손상의 가속/감속 현상을 규명할수있었다.

• 한국축산식품학회지
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• 제36권3호
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• pp.343-351
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• 2016

The objective of this study was to evaluate the effects of a short-term/extreme temperature abuse (STA) on color characteristics and oxidative stability of aged beef muscles during simulated retail display. Two beef muscles (longissimus lumborum, LL and semitendinosus, ST) were aged for 7 (A7), 14 (A14), 21 (A21), and 28 d (A28), and further displayed at 2℃ for 7 d. The STA was induced by placing steak samples at 20℃ for 1 h on the 4th d of display. Instrumental and visual color evaluations, ferric ion reducing capacity (FRC) and 2-thiobarbituric acid reactive substances (TBARS) assay were performed. Initially, redness, yellowness and hue angle of all beef muscles were similar, regardless of aging time before display (p>0.05). An increase in postmortem aging time increased lipid oxidation and caused a rapid discoloration after STA during display (p<0.05). ST muscle was more sharply discolored and oxidized after STA, when compared to LL muscle (p<0.05). The FRC value of beef muscles was decreased after 7 d of display (p<0.05). The results from the current study indicate adverse impacts of postmortem aging on color and oxidative stabilities of beef muscles, particularly under temperature abusing conditions during retail display. Thus, developing a specific post-harvest strategy to control quality attributes in retail levels for different muscle types and aging conditions would be required.

• 대한영양사협회학술지
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• 제19권3호
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• pp.195-208
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• 2013

The purpose of this study was to evaluate the quality characteristics of chicken sausage prepared with turmeric (Curcuma longa L.) powder (T) during storage at $4^{\circ}C$ for 20 days. The pH and color values (a and b values) of sausage containing turmeric powder were significantly higher (P<0.05) than the control for both uncooked and cooked sausage. The hardness, chewiness, and gumminess of control sausage significantly changed after 15 days of storage, while the hardness and gumminess of turmeric-supplemented sausages (T) significantly increased after 5 days (until 15 days) for cooked sausages. The total phenolic content and DPPH radical scavenging activity of turmeric-supplemented sausages was significantly higher (P<0.01) than the control for both uncooked and cooked sausage during storage. On the other hand, the acid value of the control was higher than the turmeric-supplemented sausages and the peroxide value of the control was significantly higher (P<0.05) than the turmeric-supplemented sausages after 15 days of storage. Microorganism analysis revealed that total plate counts of uncooked and cooked control sausages were significantly higher (P<0.05) than turmeric-supplemented sausages at 20 days of storage. As a result, sausages prepared with turmeric powder demonstrate antioxidative activity and lipid oxidative stability during storage.

• 한국식품위생안전성학회지
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• 제23권1호
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• pp.85-89
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• 2008

가열 조리된 냉장 돼지고기 패티에 사용된 상업용 유통 ${\gamma}$-oryzanol과 ${\alpha}$-tocopherol의 항산화 효과가 돼지고기 육질 내의 지질 산화로부터 기인되는 warmed-over flavor(WOF) 값과 콜레스테롤 산화로부터 기인되는 이차 산화물인 7-ketocholesterol의 생성 추이 변화로 비교 분석되었다. 지질산화로부터 측정된 파라미터는 이화학 데이터인 TBARs 값과 관능 데이터인 WOF 값에 의해 비교 분석되었으며, 콜레스테롤 산화로부터 유래된 측정 파라미터는 산화 유도기간에 따른 가열 조리된 돼지고기의 콜레스테롤 함량 변화 정도와 주요 콜레스테롤 산화물인 7-ketocholesterol 생성 정도에 의해 비교 분석 되었다. 콜레스테롤과 롤레스테롤 산화물은 cold saponification 추출 기법과 고속액체크로마토그래프 (HPLC) 테크닉을 이용하여 정량적으로 분석되었다. 아울러, 측정된 각 파라미터 변수들 간의 통계적 상관관계가 검토되었으며, 가열 조리된 돼지고기 패티의 산화로부터 기인되는 이차 산화물에 대한 ${\gamma}$-oryzanol과 ${\alpha}$-tocopherol의 항 산화력이 비교 분석되었다. 분석 결과 모든 파라미터 변수들은 서로 간에 유의적인 상관관계를 나타내었으며, 특히, ${\gamma}$-oryzanol처리 군에서 유의적인 지질 및 콜레스테롤 항 산화 효과를 보였다.

• 한국축산식품학회지
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• 제35권3호
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• pp.330-338
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• 2015

The effects of dietary supplementation of processed sulfur in pigs according to the level provided during the fattening phase were examined. The pigs were divided into three groups: control (CON), non-sulfur fed pigs; T1, 0.1% processed sulfur fed pigs; T2, 0.3% processed sulfur fed pigs. Physicochemical and sensory properties, as well as meat quality and oxidative stability of the Longissimus dorsi muscle were investigated. The feeding of processed sulfur did not affect moisture and protein contents (p>0.05). However, the crude fat content of T2 was significantly decreased compared to CON (p<0.05), while the pH value of T2 was significantly higher than those of both CON and T1 (p<0.05). Cooking loss and expressible drip of T2 were also significantly lower than that of CON (p<0.05). The redness of meat from T1 was significantly higher than both CON and T2 (p<0.01). During storage, lipid oxidation of the meat from sulfur fed pigs (T1 and T2) was inhibited compared to CON. Examination of omega-3 polyunsaturated fatty acids revealed T2 to have significantly higher content than CON (p<0.05). In the sensory test, the juiciness and overall acceptability of T2 recorded higher scores than CON. This study demonstrated that meat from 0.3% processed sulfur fed pigs had improved nutrition and quality, with extended shelf-life.