• Bulletin of the Korean Chemical Society
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• v.32 no.6
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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).

• Korea journal of population studies
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• v.15 no.2
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• pp.70-89
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• 1992

• Journal of Satellite, Information and Communications
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• v.12 no.2
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• pp.51-55
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• 2017

This paper aims to maximize the energy harvesting rate and channel capacity in RF-energy harvesting networks (RF-EHNs) under the constraints of maximum transmit power and minimum quality of service (QoS) in terms of rate capacity for each user. We study a multi-user RF-EHN with frequency division multiple access (FDMA) in a Rayleigh channel. An access point (AP) simultaneously transmitting wireless information and power in the RF-EHN serves a subset of active users which have a power-splitting antenna. To gauge the network performance, we define energy efficiency (EE) and propose an optimization solution for maximizing EE with Lagrangian dual decomposition theory. In simulation results, we confirm that the EE is effectively maximized by the proposed solution with satisfying the given constraints.

• Korean Journal of Head & Neck Oncology
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• v.12 no.2
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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.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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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)

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2003.10a
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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)

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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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)

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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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)

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.6
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• pp.501-511
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• 2014

Bio-oil derived from biomass through fast pyrolysis process has the potential to displace a significant amount of petroleum fuels. However, the use of bio-oil in a diesel engine is very limited because of its poor properties, e.g., its low energy density, low cetane number, and high viscosity. Therefore, bio-oil should be emulsified or blended with other fuels that have high centane numbers. Because bio-oil has poor miscibility with petroleum fuels, the most suitable candidate fuels for direct mixing are alcohol fuels. In this study, bio-oil was blended with ethanol, and two types of cetane improvers were added to a blended fuel to improve the self-ignition property. The two types of cetane improvers, PEG 400 and 2-EHN, made it possible for bio-oil blended fuels to combust in a diesel engine with a maximum bio-oil content of 15 wt%. A high-compression-ratio piston is also proposed for the combustion of bio-oil in a diesel engine.

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2003.10a
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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)