• Bulletin of the Korean Chemical Society
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• 제32권6호
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• pp.1965-1969
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• 2011

1,2,4,5-tetraoxane, mono and dinitrate glycerol carbonate ester derivatives of stearic acid were synthesized along with the known 9(10)-keto methyl sterate, methoxy mono-nitrate and dinitrate of methyl stearate. Their cetane numbers (CNs) were investigated to evaluate their viability for use as CN improvers. The CN performances of tetraoxane and all of the nitrate derivatives were investigated at 500 and 1000 ppm concentrations and compared to that of a traditional CN improver 2-ethylhexyl nitrate (2-EHN). The experimental results suggest that all derivatives evaluated in this study showed better CN improvement than base diesel fuel. Specifically, the 1,2,4,5-tetraoxane derivative of stearic methyl ester was superior to all derivatives studied, also being superior to 2-EHN. We also discussed the correlations between the observed CN trends and thermo-analytical data resulted from thermo gravimetric analysis curves (TGA) and differential scanning calorimetry (DSC).

• 한국인구학
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• 제15권2호
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• pp.70-89
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• 1992

• 한국위성정보통신학회논문지
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• 제12권2호
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• pp.51-55
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• 2017

본 논문에서는 RF 에너지 하비스팅 네트워크에서 최대 전송 파워량 제한 및 최소 채널 용량 달성에 관한 제약조건을 만족시키며 에너지 하비스팅율과 채널 용량을 최대화 시키는 연구를 진행하였다. 전력 분할 기법 (power-splitting scheme) 기반 안테나로 구성된 주파수 분할 다중접속 환경에서 하나의 액세스 포인트 (access point)로부터 무선 에너지와 정보를 사용자들에게 동시에 송수신하는 모델을 가정하였다. 네트워크 성능 지표로서 에너지 효율 (energy efficiency)을 정의하고 이를 최대화 시킬 수 있는 Lagrange 이중 분해 기반의 최적화 솔루션을 제안하였다. 모의실험 결과를 통해 제안한 솔루션이 설정된 제한조건들을 만족하면서 효과적으로 에너지 효율을 최대화시키는 것을 확인하였다.

• 대한두경부종양학회지
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• 제12권2호
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• pp.230-234
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• 1996

Benign nonepithelial tumors of the thyroid gland are very rare and include lesions such as vascular tumors, smooth muscle tumors and neurogenic tumors. Schwannoma and neurofibroma are benign neoplasms of mesenchymal origin which frequently occur in the head and neck, but their origin within the thyroid gland has rarely been reported. Recently, we encountered two cases of neurogenic tumor of thyroid gland(l schwannoma, 1 neurofibroma) and report them to support the view that Schwannoma and neurofibroma may occur in thyroid gland, which is an unusual site, and are recognizable entities.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 춘계학술대회 논문집
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• pp.60-61
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• 2003

Effects of repeated treatment with butylated hydroxyanisole (BRA) on the induction of glutathione S-transferases (GSTs) and teratogenicity of cyclophosphamide were investigated in rats. Pregnant rats were orally treated with BRA (50 mg/kg) for 7 days, from days 6 to 12 of gestation, and subcutaneously challenged with cyclophosphamide (15 mg/kg) 2 hr after the final treatment. On day 20 of gestation, the maternal and fetal abnormalities were examined.(omitted)

• 한국수의병리학회:학술대회논문집
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• 한국수의병리학회 2003년도 추계학술대회초록집
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• pp.45-45
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• 2003

Carbon tetrachloride (CCl4) is known to cause liver injury characterized by centrilobular necrosis. The toxicity is thought to be exerted via cytochrome P-450-mediated metabolism of $CCl_4$ to trichloromethyl and trichloro-methylperoxy radicals, which initiates lipid peroxidation, leading to hepatocellular membrane damage [l, 2]. Our study demonstrates a therapeutic efficacy of YCY, extract of a cricket, Gryllus bimaculatus, on liver injuries induced by $CCl_4$. (omitted)

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.172-172
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• 2001

This study was to evaluate oral toxicity of meat originated from cloned cows in 7-week-old Sprague-Dawley rats. The meats were mixed with 2%, 10%. and 50% in basal diet and were fed to SD rats for 28 days, respectively. There were no changes in clinical signs, blood and urine analyses, change of body weight, and feed intake or water consumption in all animals treated with the meat mixtures.(omitted)

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.168-168
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• 2001

To investigate the safety and toxicity of a recombinant human erythropoietin, YHB216, we performed 4-week repeated dose toxicity test in 4-month-old Beagle dogs. We injected intravenously everyday for 28 days with dosages of 0, 500, 2,500 and 12,500 I.U/kg body weight. There were not observed clinical signs or motality in the animals treated with YHB216. There were no significant changes in body weight, feed, or water consumption.(omitted)

• 대한기계학회논문집B
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• 제38권6호
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• pp.501-511
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• 2014

바이오매스 원료로부터 급속열분해 반응을 통하여 생산되는 바이오 오일은 화석연료를 대체할 수 있는 잠재력을 가지고 있다. 하지만, 바이오 오일은 에너지 밀도와 세탄가가 낮고 점성도가 높은 연료의 한계성이 있으므로 디젤엔진에 적용하기에는 제한적이다. 따라서, 안정적인 연소를 얻기 위해서는 바이오 오일을 세탄가가 높은 연료와 유화하거나 혼합하여 사용하여야 한다. 하지만 바이오 오일과 화석연료는 극성이 달라서 서로 혼합되지 않으며 가장 손쉽게 혼합되는 연료는 알코올계 연료이다. 본 연구에서는 바이오 오일의 연료특성을 향상시키기 위하여 에탄올 연료와 혼합하였으며, 연료의 자발화 특성을 향상시키기 위하여 세탄가 향상제인 PEG 400, 2-EHN 도 첨가하였다. 또한 최대 15%의 바이오 오일이 혼합된 혼합연료를 디젤엔진에서 안정적으로 연소시키기 위하여 고압축비 피스톤도 적용하였다.

• 한국수의병리학회:학술대회논문집
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• 한국수의병리학회 2003년도 추계학술대회초록집
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• pp.46-46
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• 2003

Polychlorinated dibenzo-p-dioxins (PCDDs) are widespread, persistant, and highly toxic environmental pollutants. TCDD is the most potent congener among PCDDs and the most thoroughly investigated model compound of this class of chemicals. These compounds elicit a variety of common biochemical and toxic response, including specific binding to the cytosolic AHR [1] and induces a variety of biological response ranging from induction of cytochrome P-450 1A (CYP1A) to liver damage and cancer [2]. This study was carried out to investigate the protective effects of YCY, extract of a cricket, Gryllus bimaculatus, on hepatotoxicity in 6-week-old SD rat exposured to TCDD (omitted)