• Journal of Environmental Health Sciences
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• v.29 no.3
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• pp.79-85
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• 2003

The purpose of this study was to disclose the manufacturing process of activated carbon using coal. It investigated the influences on the physical properties that were manufactured activated carbon by using anthracite coal, bituminous coal under carbonizated and activated condition. The adsorption capacities of organic material were superior when the ash content was lower 5∼10%, and the iodine value was about 1,000 mg/g, the adsorption capacity decreased rapidly when ash content was over 15%. The manufactured activated carbon were found characteristics such as the iodine value was over 1,031 mg/g, the specific surface area was over 1,032 $m^2$/g and the hardness was over 95% under manufacturing conditions which were carbonizated temperature of $600^{\circ}C$( 180 minute), activated temperature of 95$0^{\circ}C$(210 minute) and steam weight of 6 $m\ell$/min.100 g coal.

• Journal of the Korean Chemical Society
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• v.67 no.1
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• pp.28-32
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• 2023

The reaction conditions optimization, including the temperature of the reaction, amount of catalyst required, and reaction time for the linoleic acids (LAs) and conjugated linoleic acids (CLAs) production by catalytic dehydration of castor oil via saponification was investigated by response surface methodology (RSM). It was confirmed that all three parameters (temperature, time, and amount of catalyst) were influential factors in isolating LAs and CLAs. When the temperature was increased, the iodine value increased, and the reaction time and catalyst amount increased. The optimal reaction conditions were: 240 ℃, 2.2 h reaction time, and 7 wt% catalyst amount. The maximum iodine value reached 156.25 with 91.69% conversion to the essential fatty acids.

• Journal of Korea Foresty Energy
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• v.22 no.1
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• pp.17-23
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• 2003

Three different aged Chinese bamboo (Phyllostachys pubescense; 3, 5, and 7 years) was carbonized using three different types of kilns (special, improved and simple kiln) and their physicochemical charcoal properties were investigated. The fixed carbon of the bamboo charcoal prepared from the special kiln (800 - $1,000^{\circ}C$) tended to be decreased, while the specific surface area tended to be increased, according to the increase of bamboo ages. The bamboo charcoal prepared from the 5-year-aged showed the highest value in iodine value. In the improved kiln (600 - $700^{\circ}C$), the specific surface area and the iodine value increased with the growth period. In the simple kiln (400 - $500^{\circ}C$), the amount of volatile matter of the bamboo charcoal was approximately two times higher than that obtained from the special and improved kilns. Despite of the high amount of volatile matter in the simple kiln, the fixed carbon was more than 80%. The 5-year-aged bamboo charcoal showed the highest levels in specific surface area and iodine value. The physical properties of the bamboo charcoals prepared from the 3- and 5-year-aged Chinese bamboo were relatively worse those of Korean bamboo of the same ages. It was probably thought caused by less dense structure of the Chinese bamboo of 3- and 5-year-aged than the domestic in morphological aspects.

• Preventive Nutrition and Food Science
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• v.2 no.3
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• pp.202-206
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• 1997

To develop mil fat fractions with desirable physico-chemical properties, anhydrous milk fat (AMF) was fractionated by one- and two-stage extractions using supercritical $CO_2$(SC-$CO_2$). Tow-stage extraction of AMF was performed by first producing tow fractions, an extract and a residue at 4$0^{\circ}C$/241bar, which were subsequently used as the feed for an extraction at 6$0^{\circ}C$/241bar and 4$0^{\circ}C$/345bar, and separated into five and four fractions, respectively, based one extraction time. These fractions were quantified and analyzed for fatty acids and physico-chemical properties. SHort-chain (C4~C8) fatty acids in extract fractions from an extract were 200~150% compared with those of the original AF. Long-chain (C14~C18) fatty acids in extract fractions from a residue were 118~141%. The ratio of unsaturated fatty acids in the residue fraction was 131%. Melting point ranged from 22 to 43$^{\circ}C$, iodine value 21.8 to 36.9, and saponification value 255 to 221 in the extract and residue fractions. SC-$CO_2$ fractionation of AMF by two-stage extraction offers the possibility of developing ractions with discrete fatty acid compositions and physico-chemical properties such as melting point, iodine value and saponification value.

• Korean journal of food and cookery science
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• v.12 no.3
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• pp.367-371
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• 1996

Camellia oil refined under laboratory conditions had a lower content of linoleic acid, higher oleic acid and lower iodine value than soybean oil. The oxidative stability of camellia oil from POV and AV was much higher than that of soybean oil during autoxidation. The acid values of both oils increased with frequency of frying whereas iodine value decreased. The significant decrease of iodine value of soybean oil compared to camellia oil is thought to be because more double bonds are present in soybean oil than in camellia oil. The result of sensory evaluation for taste, color, odor and total acceptance of potato chips fried with camellia, soy-bean and corn oil revealed that the potato chips prepared from camellia oil was the most favorable.

• Journal of the Korean Society of Radiology
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• v.17 no.1
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• pp.1-9
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• 2023

For optimal image quality of computer tomography angiography (CTA), different iodine concentrations and scan parameters were applied to quantitatively evaluate the image quality characteristics of filtered back projection (FBP), hybrid-iterative reconstruction (hybrid-IR), and deep learning reconstruction (DLR). A 320-row-detector CT scanner scanned a phantom with various iodine concentrations (1.2, 2.9, 4.9, 6.9, 10.4, 14.3, 18.4, and 25.9 mg/mL) located at the edge of a cylindrical water phantom with a diameter of 19 cm. Data obtained using each reconstruction technique was analyzed through noise, coefficient of variation (COV), and root mean square error (RMSE). As the iodine concentration increased, the CT number value increased, but the noise change did not show any special characteristics. COV decreased with increasing iodine concentration for FBP, adaptive iterative dose reduction (AIDR) 3D, and advanced intelligent clear-IQ engine (AiCE) at various tube voltages and tube currents. In addition, when the iodine concentration was low, there was a slight difference in COV between the reconstitution techniques, but there was little difference as the iodine concentration increased. AiCE showed the characteristic that RMSE decreased as the iodine concentration increased but rather increased after a specific concentration (4.9 mg/mL). Therefore, the user will have to consider the characteristics of scan parameters such as tube current and tube voltage as well as iodine concentration according to the reconstruction technique for optimal CTA image acquisition.

• The Korean Journal of Food And Nutrition
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• v.35 no.1
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• pp.62-73
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• 2022

Omija seed oil was extracted from Omija seeds, a by-product of Omija, using an eco-friendly pressed extraction method. Physicochemical properties and antioxidant activities of 12 extracts using different combinations of seed moisture content (5, 7.5, and 10%) and extraction temperature (25, 49, 75, and 100℃) were then investigated. The highest extraction yield was 31.33% at moisture of 5% and temperature of 75℃. The lowest acid value was 4.18±0.25 at moisture of 5% and temperature of 49℃or moisture of 7.5% and temperature of 25℃. Peroxide value, iodine value, and saponification value were the lowest at 0.64±0.56 meq/kg, 159.38± 6.03, and 57.60±9.40, respectively, at moisture of 5% and temperature of 25℃. The content of total polyphenolics was the highest at 4,413±125 mg TAE/100 g when the moisture content was 10% and the extraction temperature was 25℃. DPPH radical scavenging activities of oil extracts at 20~100 mg/mL were 28.68±7.30~87.65±2.20%. The maximum antioxidant activity and IC₅₀ were 87.65±2.20% and <20 mg/mL, respectively, for extract obtained at moisture of 10% and temperature at 100℃. As a result, the extraction yield, acid value, peroxide value, iodine value, saponification value, and so on were excellent at moisture content of 5% and extraction temperature of 25℃ or 49℃. However, the content of total polyphenolic compounds and antioxidant activity were the highest at moisture of 10% and extraction temperature of 100℃. In conclusion, extracting Omija seed oil from Omija seeds, a by-product of Omija, is effective with a pressed extraction method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.654-659
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• 1994

To elucidate the relationship between physical and chemical properties of frying vegetable oils, soybean oil and cottonseed oil were heated in air temperatures from $160^{\circ}C\;to\;220^{\circ}C$ for 60 hours. Acid value, carbonyl value, iodine value, viscosity and content of polymer were remarkably changed as higher heating temperature and/or longer heating time. Correlation coefficient of viscosity to acid value was 0.9843 for soybean oil and 0.9819 for cottonseed oil. In case of viscosity and carbonyl value, viscosity also showed good relationship to carbonyl value as 0.9779 for soybean oil and 0.9797 for cottonseed oil. And correlation coefficient of viscosity to iodine value of soybean oil was 0.9852 and cottonseed oil was 0.9948.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.87-90
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• 2006

The experimental study has been done for two kinds of pelletized RDFs to Investigate the carbonization effect to the chlorine concentrations, the heating value and the yield of Produced char in variable conditions of the carbonizing temperature and reaction time. One(RDF-1) is made of 100% wasted plastics and the other(RDF-2) is made of 60% wasted paper with 40% wasted plastics. The screw type carbonizer heated Indirectly by oil burner was used for the experiment and RDF feeding rate was 3kg/hr. The carbonizing temperature was 300, 350 400 and $45^{\circ}C$ and the reaction tine was 5, 10 and 15 minutes respectively. As the increase of carbonizing reaction time and temperature, the chlorine reduction rate was increased and oppositely the yield of char was decreased At the temperature of $400^{\circ}C$ and reaction time of 10 minutes the chlorine reduction rate was 60% and the char yield rate was 80% for the RDF-1 and those of RDF-2 were 80% and 75%, respectively. Additional activation experiment to the char produced from RDF-2 was done in the activation reactor by hot steam supply. As the increase of activation time the iodine number was increased. At the activation time of 20 minutes the iodine number was 552mg/g and the yield of activated carbon was 16%.

• Journal of the Korean Ceramic Society
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• v.46 no.6
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• pp.568-573
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• 2009

In this study, we used coal based activated carbons as starting material and phenolic resin (PR) as a bonding agent to prepare spherical shaped activated carbons. The textural properties of SAC were characterized by BET surface area, XRD, SEM, iodine adsorption, strength intensity and pressure drop. According to the results, the spherical activated carbon prepared with activated carbon and PR at a ratio of 60:40 was found to have the best formation of spherical shape, which was found in sample SAC40. After activation, SAC40 has high BET surface area, iodine adsorption capability and strength value, and lowest pressure drop.