• 한국분무공학회지
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• 제14권3호
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• pp.122-130
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• 2009

Vegetable oil and its derivatives as an alternative diesel fuel have become more attractive recently because of its environmental benefits and the fact that they are made from renewable resources. Viscosity is the most significant property to affect the utilization of vegetable oil and its derivatives in the compression ignition engines. This paper presents the existing correlations for predicting the viscosity of vegetable oil and its derivatives for compression ignition engines. According to the parameter considered in the correlations, the empirical correlations can be divided into six groups: correlations as a function of temperature, of proportion, of composition, of temperature and composition, of temperature and proportion, and of fuel properties. Out of physical properties of fuel, there exist in the literature several parameters for giving the influence on kinematic viscosity such as density, specific gravity, the ratio of iodine value over the saponification value, higher heating value, flash point and pressure. The study for the verification of applicability of existing correlations to non-edible vegetable oil and its derivatives is required.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 제23차 추계총회 및 국제학술심포지움
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• pp.164.2-165
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• 2003

Structured lipids (SLs) are defined as triacylglycerols to change the fatty acid composition in the glycerol backbone and lipases are known as a powerful tool for the syntheses of SLs. Structured lipid from corn oil, capric acid, and conjugated linoleic acid (CLA) by transesterification reaction and using several amounts of immobilized lipase RM IM (from Rhizomucor miehei) was studied, and 4% of lipase amount was selected for further study as the optimal amount. Comparison the chemical properties (free fatty acid value, iodine value, saponification value, tocopherols, and color analysis), solidification behavior, and volatile fractions (from headspace SPME GC-MS) between com oil and SL com oil was obtained.

• 대한가정학회지
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• 제18권1호
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• pp.41-46
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• 1980

In order to verify to what extent the rancidity of the soybean oil is occurred and how the various metal ions effect on the rancidity-as a result of applying heat to the soybean oil-the followings are obtained through experiments : 1. From analyzing the refractive index of soybean oil, The results are: the specific gravity-0.925 refractive index-1.475, saponification value-190, acetyl value-5.0, iodine value-120, peroxide value-5.0. 2. The degree of expediting rancidity take the following order : $Cu^{++}$/$Fe^{++}$/$Cr^{++}$/$Zn^{++}$/$Ni^{++}$/$Al^{+++}$. 3. The degree of expediting rancidity of $Cu^{++}$and $Fe^{++}$ is showed the abrubt increase of peroxide value in accordance with the increase of densidity. The most abrubt increase of peroxide show when the duration of heating reaches to the range between 20 minutes and 30 minutes. After heating for 60 minutes no definite variation is showed. 4. The degree of rancidity in heating the soybean oil added $Cu^{++}$, Fe and BHA shows the decrease of peroxide value by 2, 3 after adding $Cu^{++}$0.5 ppm. and heating for 30 minutes. As the result of measuring the value of peroxide after adding $Cu^{++}$ by 1.0 ppm and BHA by 0.01% and heating, peroxide shows the decrease by 7.8 when adding anti-oxidant. $Fe^{++}$ as well as $Cu^{++}$ shows that BHA prevents the metal ions from the expedition of rancidity.

• 한국식품과학회지
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• 제4권4호
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• pp.259-264
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• 1972

국산(國産) 라면제품을 형광등조사구(螢光燈照射區) 고온암소구(高溫暗所區) 자외선조사구(紫外線照射區) 등의 처리구(處理區)로 나누어 20주(週)동안 저장하고, 경시적(經時的)으로 산가(酸價) 과산화물가(過酸化物價) carbonyl가(價) TBA가(價) 지방산조성(脂肪酸組成) 옥도가(沃度價) 등의 지방산화현상(脂肪酸化現象)을 살펴 본 바 다음과 같은 결과를 얻었다. 전반적으로 형광등조사구(螢光燈照射區) 및 고온암소구(高溫暗所區)의 라면은 완만한 산화현상(酸化現象)을 보였으며, 저장 16주(週)에 변패취(變敗臭)를 확인하였고, 자외선조사구(紫外線照射區)의 라면은 저장초(初)부터 급격한 산화(酸化)가 일어났으며, 저장 4주(週)에 변패취(變敗臭)를 확인하였다. 2) 산가(酸價) 과산화물가(過酸化物價) TBA가(價)등은 각처리구(名處理區) 공(共)히 전실험기간동안 증가하였으며 자외선조사구(紫外線照射區)에서 그 증가현상(增加現象)은 현저하였다. 특히 TBA가(價)는 자외선조사구(紫外線照射區)에서 저장 4주(週)이후 급격히 증가하여 10주(週)에 그 정점(頂點)을 이루고 다시 감소하였다. 이 때의 bound malonaldehyde는 14주(週)까지 증가하다가 그 이후 완만히 변화하였다. 3) 저장초(貯藏初) 그리고 저장(貯藏) 12주(週)의 고온암소구(高溫暗所區) 및 자외선조사구(紫外線照射區)의 라면유지(油脂)에 대한 지방산조성(脂肪酸組成)을 살펴 본 결과 고온암소구(高溫暗所區)에선 큰 변화가 없었으며, 자외선조사구(紫外線照射區)에선 저장초(貯藏初)의 지방산조성(脂肪酸組成)에 비(比)하여 linoleic acid 등 불포화 지방산의 상대적(相對的)인 감소현상을 볼 수 있었으며 저장 중 옥도가(沃度價)의 감소(減少)가 이러한 사실(事實)을 뒷받침하고 있다.

• 신재생에너지
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• 제9권3호
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• pp.36-42
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• 2013

To secure raw materials of biodiesel production, the possibility of camellia (C. japonica L.) and tea (C. sinensis L.) seed oil was studied to produce biodiesel. In this research, crude oil contents and fatty acid compositions of seeds were analyzed by Solxlet and Gas chromatography (GC). The oil contents in the seeds of camellia were 69.8%~73.8%, and tea were 26.3%~29.4%. Among the fatty acids of camellia and tea oil, oleic acid was dominant. The unsaturated fatty acids accounted for 88.4% and 80.2% of the whole fatty acids of camellia and tea seed oil. Total seed oil content and fatty acid composition of tea seed were influenced by collecting date. Across maturation period, oil content of tea seed averaged 18.3% on $6^{th}$ September increasing to 27.9% by $11^{th}$ October. For largest seed yield and oil content, the optimum time to harvest tea is in middle october, and camellia is late september and thereafter. The extraction efficiency of oil from seeds by extraction methods was determined. Biodiesel were synthesized in 92.1~92.8% yields from camellia and tea oils by transesterification. The biodiesel was characterized by its physical and fuel properties including oxidation stability, iodine value and cold filter plugging point (CFPP). Oxidation stability of camellia was 8.6~8.8 hours and tea was 2.9~3.6 at $110^{\circ}C$. Camellia oil had considerably better oxidation stability and CFPP than tea oil.

• 한국식품과학회지
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• 제42권1호
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• pp.115-118
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• 2010

메조 전분의 청가와 요오드 친화도는 각각 0.304와 4.22%로 일반 메 전분과 비슷하였으나 기장 전분은 각각 0.098과 1.07%로 찰 전분에 가까운 성질을 보였다. 차조와 찰기장 전분의 청가는 각각 0.056과 0.037, 요오드 친화도는 각각 0.49와 0.21%이었다. 전분의 평균중합도는 메조 전분이 1830이었으며, 나머지 세 전분은 3880-4660으로 비슷하였다. 생전분의 알파 아밀라아제 소화율은 찰기장 전분이 제일 커 35.6% 이었으며, 기장 전분이 제일 적어 18.2% 이었다. 전분 입자의 평균 크기는 기장이 $8.25\;{\mu}m$로 제일 작았으며, 나머지 세 전분은 $10.33-11.53\;{\mu}m$이었다. 입자 분포에서도 기장 전분만 $1.9\;{\mu}m$ 이하와 $20.0\;{\mu}m$ 이상의 크기를 갖는 입자가 없어 좁은 분포도를 보였다. 기장 전분의 호화개시온도가 다른 전분보다 $3.5-4.9^{\circ}C$ 높았으며, 최고 점도와 노화정도를 나타내는 Setback 점도는 메조 전분이 제일 컸다. 메조 전분을 제외하고는 12% 농도에서 겔을 형성하지 못하였으며, 25% 농도에서의 겔 강도는 차조, 기장, 찰기장 순이었다.

• 자원리싸이클링
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• 제17권1호
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• pp.20-28
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• 2008

신평장림 공단에서 배출되는 피혁폐기물은 46.3%의 탄소를 함유하고 있으며 열중량분석에 의하면 $500^{\circ}C$에서 중량손실이 약 50%이었다. $K_2CO_3$을 이용한 화학적 활성화법으로 $800^{\circ}C$에서 약 30분간 질소분위기 중에서 피혁폐기물을 원료로 한 피혁폐기물 활성탄[leather waste chemically activated carbon, LW4AC]을 제조하였다. 피혁폐기물 활성탄의 요오드 값, 메틸렌블루 탈색력은 각각 968 mg/g, 158 mL/g이었다. $K_2CO_3$와 피혁폐기물 혼합비 $[K_2CO_3/LW]$가 증가할수록 세공부피가 발달함을 알 수 있었다.

• Korean Journal of Radiology
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• 제19권6호
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• pp.1021-1030
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• 2018

Objective: We evaluated the effect of various patient characteristics and time-density curve (TDC)-factors on the test bolus-affected vessel enhancement on coronary computed tomography angiography (CCTA). We also assessed the value of generalized linear regression models (GLMs) for predicting enhancement on CCTA. Materials and Methods: We performed univariate and multivariate regression analysis to evaluate the effect of patient characteristics and to compare contrast enhancement per gram of iodine on test bolus (${\Delta}HUTEST$) and CCTA (${\Delta}HUCCTA$). We developed GLMs to predict ${\Delta}HUCCTA$. GLMs including independent variables were validated with 6-fold cross-validation using the correlation coefficient and Bland-Altman analysis. Results: In multivariate analysis, only total body weight (TBW) and ${\Delta}HUTEST$ maintained their independent predictive value (p < 0.001). In validation analysis, the highest correlation coefficient between ${\Delta}HUCCTA$ and the prediction values was seen in the GLM (r = 0.75), followed by TDC (r = 0.69) and TBW (r = 0.62). The lowest Bland-Altman limit of agreement was observed with GLM-3 (mean difference, $-0.0{\pm}5.1$ Hounsfield units/grams of iodine [HU/gI]; 95% confidence interval [CI], -10.1, 10.1), followed by ${\Delta}HUCCTA$ ($-0.0{\pm}5.9HU/gI$; 95% CI, -11.9, 11.9) and TBW ($1.1{\pm}6.2HU/gI$; 95% CI, -11.2, 13.4). Conclusion: We demonstrated that the patient's TBW and ${\Delta}HUTEST$ significantly affected contrast enhancement on CCTA images and that the combined use of clinical information and test bolus results is useful for predicting aortic enhancement.

• 한국식품과학회지
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• 제4권1호
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• pp.18-23
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• 1972

인스턴트라면을 태양광선군(太陽光線群), 포장지제거군(包裝紙除去群), 실내보존군(室內保存群), 항온기보존군(恒溫器保存群), 골판지상자 포장군등(包裝群等), 각각(各各)의 조건하(條件下)에서 오개월간(五個月間) 저장(貯藏)하고 함유유지(含有油脂)의 경시변화(經時變化)를 조사(調査)하여 다음과 같은 결론(結論)을 얻었다. 1) Orange 색(色)으로 착색(着色)한 polycello 포장지(包裝紙)로 밀봉(密封)하고 골판지상자에 넣어 실온(室溫) 암소(暗所)에서 저장(貯藏)하면 과산화(過酸化) 물가(物價)(P.O.V.), 산가(酸價)는 Fig. 1과 2와 같이 완만하게 증가(增加)하여 150일(日) 경과후(經過後)에도 안정(安定)한 품질(品質)을 보였다. 관능검사(官能檢査)에 있어서의 변패취(變敗臭)도 150일(日) 경과후(經過後)까지 인정(認定)되지 않았다. 2) 태양광선(太陽光線)을 조사(照射)하거나 포장지(包裝紙)를 제거(除去)하고 실내(室內)에서 방치(放置) 저장(貯藏)하면 P.O.V. 및 A.V.는 Fig 1과 2와 같이 급격(急激)한 증가(增加)를 보였으며 30일이내(日以內)에 변패취(變敗臭)가 인정(認定)되었다. 3) Polycello 포장지(包裝紙)로 밀봉(密封)하고 실내산광하(室內散光下)에 저장(貯藏)하거나 또는 항온기내(恒溫器內)에서 $30^{\circ}C$ 정도(程度)(하절기(夏節期) 평균기온(平均氣溫)에 상당(相當))로 가온(加溫) 저장(貯藏)하면 P.O.V.의 변화(變化)는 비교적(比較的) 완만하였으나 변패취(變敗臭)는 $90{\sim}120$일경과후(日經過後)에 발생(發生)하였다. 4) P.O.V., A.V. 및 굴절률(屈折率)이 증가(增加)됨에 따라서 iodine value는 Fig. 3과 같이 점차 감소(減少)하였다. 5) 관능검사(官能檢査)에 있어서 변패취(變敗臭)의 발생(發生)은 P.O.V. 함량(含量)과 어느정도 상관관계(相關關係)가 인정되었으나 반드시 일치(一致)하지는 않았다.

• 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.