• 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).

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.1079-1081
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• 1998

This paper describes the dissipation factor measuring device for insulating oil in operating pole transformer by DSP(digital signal processor). After applying voltage to the sensor which is installed in a transformer, acquire source voltage and current of sensor using FFT techniques, then we could evaluate the dissipation factor of insulating oil. To improve measuring accuracy and processing speed, we use TMS320C31 DSP, FFT and data analysis techniques. Also we suggest deterioration criterion of insulating oil and compared the developed diagnosis device with schering bridge on deteriorated insulating oil. The result of this paper show that the developed measuring device can be used as diagnosis device for the pole transformers.

• 동아시아식생활학회지
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• 제16권6호
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• pp.717-723
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• 2006

Chemical characteristics of soybean oil after deep-frying with potato sticks (200 g, 10% w/w of soybean oil) were studied according to the 34 deep-frying times. After consecutive 34 deep-frying, total polyunsaturated FA contents was gradually decreased while the total saturated FA and trans FA were increased. Acid value and peroxide value were increased while iodine value decreased, respectively. The Hunter $L^{\ast}$ value decreased while each $a^{\ast}\;and \;b^{\ast}b$ value were gradually increased. Electronic nose equipped with 12 metal oxide sensors was used for the discrimination of odor pattern of frying oils against the times of deep-trying. The proportions of 1st and 2nd principal component analysis showed 75.97% and 21.23%, respectively. While 6 among total 12 sensors well responded to discrimination of odor in the repented frying oils, suggesting that the odor pattern of each oil after deep-frying would be discriminated against fresh soybean oil, especially after 14 times. From the results, electronic nose could differentiate the degree of quality deterioration of the repeated deep-frying oils.

• 한국응용과학기술학회지
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• 제4권1호
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• pp.19-22
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• 1987

To investigate the protective action of various antioxidants on the photooxidation of rice bran oil, it was irradiated with red and visible light in presence and absence antioxidants with or without sensitizer (methylene blue). 1. Rice bran oil with and without sensitizer in chloroform-ethanol (4:1, v/v) media was largely oxidized under visible light irradiation. on the other hand, rice bran oil without sensitizer was hardly oxidized under red light irradiation. 2. Rice bran oil with sensitizer was oxidized much faster than that without. And the absorbance of it irradiated with visible was increased more than that with red light. 3. The effectiveness of antioxidants on the rice bran oil photooxidation was same order as follows: Irradiation with visible light, no addition of sensitizer ${\beta}$-carotene > dl-{$\alpha}$-tocopherol > BHT > BHA Irradiation with visible light, addition of sensitizer ${\beta}$-carotene > BHT > dl-${\alpha}$tocopherol > BHA Irradiation with red light, addition of sensitizer ${\beta}$-carotene > BHA > BHT > dl-${\alpha}$-tocopherol From these results, we concluded that rice bran oil was largely oxidized under visible light irradiation, therefore it must be protected from photooxidative deterioration by the addition of antioxidants.

• 전기의세계
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• 제22권4호
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• pp.30-34
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• 1973

The main purporse of this paper is to study on the influence of temperature effect on electrical-properties, i.e., dielectric breakdown voltage, dielectric constant and resitivity of homemade insulating oil containing antioxidant. Transformer oil manufactured in Korea is taken for a sample, and this sample is classified into seven samples in which antioxidant is contained and not contained, and antioxidant is divided into three kinds of amount: 0.3%, 0.5%, 0.8%. Changing the tempe5rature of the samples by oil bath, the electric properties measured from the samples are as follows: (1) the variation of either the dielectric breakdown voltage or the resistivity are considerably large, but the dielectric constants are almost unchanging. (2) In view of electrical characteristic, the deterioration rate of the samples containing antioxidant is somewhat lower than that of other samples. (3) Nearly the same value is shown in the dielectric-breakdown voltage of the samples, in which contained the different amount of antioxidant: 0.3%, 0.5%, 0.8%, but the decrease rate of resitivity is lowest, 0.3%, of all. As the result of the experiment, This study can suggest that 0.3% be the optimum amount of antioxidant which will be added transformer oil manufactured in Korea and is useful for the understanding about the electrical properties of transformer oil containing antioxidant.

• 한국자동차공학회논문집
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• 제22권3호
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• pp.166-170
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• 2014

In this paper, we investigate the electric and magnetic properties of the engine oil, and estimate its changing time in transport truck. The four diesel trucks are selected, and the capacitance and inductance are investigated with parallel capacitor and induction coil, respectively. The measured capacitance gradually increases up to 10,000~14,000 km due to the activation of antioxidant, and then decreasing phenomena happen. The inductance decreases and the saturation began in 10,000~14,000 km range. Although the behavior of inductance is different from that of capacitance, but changing points are similar. From those results, we can estimate the changing time of engine oil is around 10,000~14,000 km and the inductance can be used for monitoring of engine oil in transport trucks.

• 보존과학회지
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• 제28권4호
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• pp.395-401
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• 2012

정유 상태의 세신(Asarum sieboldii) 추출물이 유기질 문화재 보존을 위한 천연 살생물제로써의 적합성 여부를 탐색하기 위하여 목재부후균과 궐련벌레에 대한 항진균활성 및 살충활성을 조사하였다. 목재부후균 4종에 대한 세신 정유추출물의 항진균활성($IC_{50}$)을 측정한 결과 $1.50{\sim}2.84{\mu}l/disc$으로 나타났으며, 이 중 L. lepideus에서 활성이 가장 우수하였다. 궐련벌레 성충에서는 50%(v/w)과 100%(v/w)의 농도로 처리했을 때 약 90% 이상의 살충활성을 보였다. 가스크로마토그래피-질량분석기를 이용하여 정유추출물의 성분을 분석한 결과 총 35종의 화학성분이 검출되었으며, 주성분은 methyleugenol(56.32%), eucarvone(11.53%), safrole(5.79%), ${\delta}$-3-carene(2.09%) 순으로 나타났다. 따라서 세신 정유추출물은 목재부후균과 궐련벌레 등 곤충에 의해 야기되는 생물학적 열화로부터 유기질 문화재를 보존할 수 있는 천연 살생물제로써 활용 가능성을 확인하였다.

• 보존과학연구
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• 통권31호
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• pp.89-102
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• 2010

This study evaluated the activity of biocidal compounds isolated from natural products and confirmed applicable possibility as conservative agents for orgainic cultural heritages damaged by biological degradation. we used methanol extracts of 11 Korean trees and 17 medicinal plants as natural resources. Among these extracts, Phellodendron amurense was investigated on antifungal activity against Coniophora puteana, Lentinus lepideus, Tyromyces palustris and Aspergillus niger. Asarum sieboldii was investigated on insecticidal activity against adult of Lasioderma serricorne. First, the extract of Phellodendron amurense was partitioned into hexane, dichloromethan and ethylacetate fraction. Among them, the ethylacetate fraction had the most significant antifungal activity. In addition, Asarum sieboldii essential oil showed an effective antifungal and insecticidal activity. As a result, the extract of Phellodendron amurense and Asarum sieboldii essential oil could be useful for conservation of organic cultural heritage against biological deterioration by wood rot fungi and Lasioderma serricorne.

• Applied Biological Chemistry
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• 제6권
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• pp.25-28
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• 1965

진해만산(鎭海灣産) 마른멸치제조(製造)에 있어서, BHA의 처리(處理)가 산패방지(酸敗防止)에 미치는 효과(效果)에 관(關)한 실험(實驗)을 하여, 다음과 같은 결과(結果)를 얻었다. 1. 진해만산(鎭海灣産) 마른멸치(중형(中型))제조(製造)에 있어 BHA 처리농도(處理濃度)는 자숙액(煮熟液)에 대하여 5/10,000(g/cc)가 가장 적당(適當)하다고 보아진다. 2. BHA 5/10,000 이상(以上) 고농도(高濃度)로 처리(處理)하여도 산패방지효과(酸敗防止效果)는 증대(增大)하지 않는다. 3. 2개월이내(個月以內)의 단기간저장(短期間貯藏)에는 BHA 1/10,000로 처리(處理)하여도 좋다. 4. BHA 5/10,000로 처리(處理)한것은 약(約) 9개월간제품(個月間製品)에 큰 손색없이 보장(保藏) 가능(可能)하였다.

• Journal of Nutrition and Health
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• 제34권8호
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• pp.843-849
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• 2001

This study was performed to investigate the effect of n-3 fatty acids and dietary protein levels on renal function. Fifteen-month old male Sprague-Dawley rats were divided into 4 diet groups. Two-month old rats were used as a control group. The experimental diets contained either a% or 25% casein and lipid levels of the diets were 20% by weight. For the control group, the lipid was composed of beef tallow and corn oil on a 1:1 basis, and fish oil was comprised 75% of the fat mixture for the fish oil group. Rats were fed the diets ad libitum for 8 weeks. GFR and urinary protein excretion were higher in high protein groups, while fish oil exhibited no effects. Renal medulla TXB$_2$and PGE$_2$ concentrations tended to be higher in high protein groups and lower in fish oil groups. Light microscopic examinations showed that glomerulosclerosis, tubular atrophy, tubular cast, interstitial inflammation and interstitial fibrosis fended to be higher in aged rats and in high protein groups and lower in fish oil groups. Serum levels of total lipid, triglyceride and total cholesterol were higher in aged rats and lower in fish oil groups while serum HDL-cholesterol level was higher in young rats and in fish oil groups. However, dietary protein level had no effect on serum lipid levels. Serum TBARS concentration was higher in aged rats and in fish oil groups. In conclusion, fish oil caused changes in serum lipid concentrations and eicosanoids metabolism. The effect of fish oil on renal function was less obvious than dietary protein. However, fish oil seemed to be effective in lessening deterioration of renal function due to aging and/or high protein diets through changes in lipid and eicosanoids metabolism.