• Applied Chemistry for Engineering
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• v.24 no.3
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• pp.219-226
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• 2013

Organic semiconductor-based soft electronics has potential advantages for next-generation electronics and displays, which request mobile convenience, flexibility, light-weight, large area, etc. Organic field-effect transistors (OFET) are core elements for soft electronic applications, such as e-paper, e-book, smart card, RFID tag, photovoltaics, portable computer, sensor, memory, etc. An optimal multi-layered structure of organic semiconductor, insulator, and electrodes is required to achieve high-performance OFET. Since most organic semiconductors are self-assembled structures with weak van der Waals forces during film formation, their crystalline structures and orientation are significantly affected by environmental conditions, specifically, substrate properties of surface energy and roughness, changing the corresponding OFET. Organo-compatible insulators and surface treatments can induce the crystal structure and orientation of solution- or vacuum-processable organic semiconductors preferential to the charge-carrier transport in OFET.

• Applied Chemistry for Engineering
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• v.29 no.2
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• pp.225-228
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• 2018

Plasticizers added to thermoplastic polymers are known to shorten the life of products due to the elution to outside, and some of them are harmful to our environment and human body. Since the use of phthalate plasticizers suspected of being carcinogens has been gradually prohibited, there is a need for environmentally friendly plasticizers that can replace them. Most of the substances have a low compatibility with resin, high cost and lack of safety verification. Therefore, in this study, four kinds of norbornene dialkyl ester compounds possessing excellent physical properties, which are also reported as safe compounds from the toxicity evaluation, were added to PVC resin to evaluate the possibility of human exposure by leaching, and also the potential usage as plasticizer candidates alternative to commercial ones including DEHP, DINCH and DOTP. The test was carried out according to the American standard test method (ASTM). The results showed that di-2-ethylhexyl-5-norbornene-2,3-dicarboxylate (DEHN) in aqueous solvents and diisopentyl-5-norbornene-2,3-dicarboxylate (DIPN) compounds in oil solvents were superior or equivalent to DEHP. In addition, all four norbornene compounds showed lower values than 100 ppm, which is considered to have an influence on the environment, indicating that the polar norbornene structure affects the elution.

• Korean Journal of Poultry Science
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• v.37 no.2
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• pp.151-158
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• 2010

TCM-KWG (tissue culture medium waste after harvest of Korean wild ginseng) (panax ginseng) is left over of tissue culture medium used to grow Korean wild ginseng (KWG). The present study was conducted to investigate the effect of TCM-KWG on meat quality and the possible of application as additives in broiler chickens. A day old broiler chickens randomized in 6 groups (n=60/groups) were administered orally with 2, 4, 8, 16, 32 mL/L TCM-KWG through drinking water with one untreated control group. After administration for five weeks, we analyzed chemical composition and meat quality. Crude ash increased approximately 20% in TCM-KWG treatment groups as compared to control group whereas the concentration of moisture, crude protein and crude fat did not show any significant difference. Crude ash is essential to enhance skeleton formation and physiological function. TCM-KWG treatment gradually decreased the pH value of breast meat whereas it did not change the purge loss and cooking loss. The pH value of meat is important for preservation of meat for longer periods and high durability strength. These results suggest that TCM-KWG treatment may improve the quality of meat and can be apply as food additives in chickens.

• Journal of the Korean Institute of Gas
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• v.23 no.6
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• pp.1-7
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• 2019

Most oil refineries and chemical plants have flare systems designed to mitigate pressure rises in process facilities in case of emergencies that require the release of large amounts of gas due to sudden process shutdowns such as power outages. However, the rise of the flame of the flare system causes civil complaints from residents around the factory due to visible pollution, and economic loss occurs in the company, which requires constant management. In this study, two items were diagnosed and analyzed in order to derive the optimal operation method of flare system. First, to detect the cause of the rise in flame height, the acoustic leak detector was used to check gas leaks in safety valves and pressure control valves. Second, to identify the cause of flame instability, the pulsation phenomenon was diagnosed through the CFD simulation and modeling experiments of the sealing drum. By confirming the leak at 4.3% of the safety valve and 10% of the pressure control valve, the cause of abnormal sparking was derived. The information presented in this study can be easily applied to any company that has a flare system, and is expected to prevent complaints and product loss.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.7
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• pp.970-974
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• 2012

Prunus mume is said to aid in the recovery of fatigue and improvement of liver and stomach functions. To obtain the best benefits of the whole fruit, fresh green Prunus mume was de-seeded and the fruit pulp was vacuum dried. The vacuum-dried pulp was powdered and sieved through a 250 ${\mu}m$ sieve. Then the sieved green Prunus mume powder (GPP) was granulated with water (GPPGW) and with Prunus mume extract (GPPGE) with a fluid bed coater. The physicochemical and sensory properties of GPP, GPPGW, and GPPGE were then evaluated. As a result, the water dispersibility (dispersible time) of GPP, GPPGW, and GPPGE was 21.19 sec, 6.46 sec, and 4.85 sec, respectively. The powder fluency (angle of repose) of GPP, GPPGW, and GPPGE was $11.25^{\circ}$, $8.65^{\circ}$, and $9.52^{\circ}$, respectively. The overall consumer acceptance of GPP, GPPGW, and GPPGE was 3.50, 4.62 and 5.00, respectively. Inconclusion, Prunus mume can be used as granulated whole fruit pulp with good powder fluency and dispersibility.

• Resources Recycling
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• v.17 no.5
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• pp.66-75
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• 2008

Using a pinus koraiensis and pinus rigida which are normally being discarded in South Korea, the optimal condition of producing charcoals has been studied to develop activated carbons which can be recycled as a higher value-added product. A study on manufacture of activated carbons from a discarded timber consists of two processes, the production process of charcoals from a discarded timber by low temperature pyrolysis process and the production process of activated carbons from the charcoals by chemical activation reaction. This study deals with the production process of charcoals from a discarded timber by low temperature pyrolysis process. As a results of experiment, it was investigated that charcoals produced through drying at $150^{\circ}C$ for 6hr and pyrolysis process at $500^{\circ}C$ for 1hr had the highest values in physical properties such as iodine number and BET surface area. Furthermore, through observing SEM images, the maximum development of porosity had been founded in this condition. It was confirmed that values of physical properties on using a pinus koraiensis are superior to the ones when using a pinus rigida. When charcoals were produced from a pinus koraiensis in this condition, BET surface area was approx. $640m^2/g$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.732-738
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• 2015

Quality characteristics of Korean cabbage treated with red clay-processed materials (RCPM) were evaluated. Two different types of RCPM treatments including a control were applied for the cultivation of cabbage. General components, nutrients, antioxidant activities, textures, and sensory evaluation were assessed. For the nutrition components analysis, RCPM-treated cabbage showed higher contents of potassium and riboflavin along with lower content of sodium compared to the control. RCPM-treated cabbage exhibited higher total polyphenol contents than those of the control, indicating higher antioxidant activities. For the textural analysis under refrigeration over 4 weeks, RCPM-treated samples showed more stable textures based on higher hardness values than the control and RC. Results of this study indicate that RCPM would be of benefit to produce high-value added cabbage of premium quality.

• Journal of Conservation Science
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• v.27 no.4
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• pp.431-440
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• 2011

The thermal expansion coefficient of epoxy/inorganic additives composites was controlled by changing the amount of the inorganic additives such as talc and fused silica. The epoxy resin comprises hydrogenated bisphenol A (HBA)-based epoxide, difunctional polyglycidyl epoxide (DPE) as a diluent and isophorone-diamine (IPDA) as a crosslinking agent, which was subsequently mixed with inorganic additives (talc and fused silica). The thermal expansion coefficient was decreased by increasing amount of inorganic additives, nearly to fresh granite. Fused silica was more effective than talc in lowering the thermal expansion coefficient. Additionally, lexural and tensile strengths of the composites were getting lower and higher with the amount of the inorganic fillers, respectively. It was thus concluded that an epoxy composite containing inorganic fillers was developed to show much lower thermal expansion coefficient, similar to fresh granite, than the neat epoxy resin, and also proper mechanical strengths for applications.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.223-229
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• 2014

The objective of this study was to evaluate quality properties including amylose, alkali digestion value (ADV), texture and GABA (Gamma Amino-Butyric Acid) of brown rice and 1~5 mm germinated brown rice of Keunnun and Samkwang culitvars. The protein content of germinated brown rice showed increasing tendency according to shoot length, however, the difference was not statistically significant. The amylose content of all samples ranged from 15.0% to 16.0% in Keunnun and 17.0% to 18.0% in Samkwang, without significant differences. Compared to regular brown rice, germinated brown rice from both cultivars demonstrated reduced gel consistency, which contributed to the improved cooked rice texture. Especially, germinated brown rice had significantly lower setback values, which is correlated with high palatability of cooked rice. However, there was no significant difference in gel consistency between 1 mm and 2~5 mm germinated brown rice. GABA content in Keunnun increased by 3~5 times after germination process. In Samkwang, GABA content increased by 50 times (from $0.005{\mu}g/g$ to $0.243{\sim}0.247{\mu}g/g$) after germination. The hardness of germinated brown rice was significantly lower than that of brown rice. However, there was no significant difference in hardness according to shoot length. Consequently, when processing germinate brown rice, it is recommended to maximize functional ingredients by germination while maintaining shoot length less than 2 mm.

• The Korean Journal of Pesticide Science
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• v.9 no.3
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• pp.243-249
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• 2005

The chemical and toxicological studies were conducted with acetamiprid 2% granules including different controlling agents for development of controlled-release acetamiprid 2% granule. The fundamental formulation recipe of acetamiprid 2% granule was prepared by the insoluble matrix using polyethylene wax. Starch, cellulose and mineral (calcium carbonate) were used as controlling agents. As a result of studies, release rate of active ingredient from granules into water static condition at $25^{\circ}C$ was increased by addition of starch and cellulose, but was decreased by addition of calcium carbonate. We could select calcium carbonate as controlling agent and make three granules which there were difference in release profiles of active ingredient according to contents of polyethylene wax. 24 hours-release rates of acetamiprid from three granules into water static condition at $25^{\circ}C$ were respectively 75, 50 and 25% when contents of wax were 2, 10 and 20%. The granule which 24 hours-release rate was 25% showed lower acute toxicity against mice and rats.