• 설비공학논문집
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• 제7권4호
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• pp.600-610
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• 1995

When combustion gas is cooled down below the dew point of sulfuric acid vapor in the heat recovery systems, condensation occurs. Since the condensed sulfuric acid solution causes low-temperature corrosion in materials, it is important to measure the SOx dew point by electric measurement. In this study, two kinds of probes having electric gaps of 1mm or 2mm were used. and experiments were carried out by the parameters of sulfuric acid vapor and water vapor concentration. The changes of electric current caused by sulfuric acid condensed on the surface of probe according to the cooling rate and the probe head surface temperature were sudied. The opimum cooling rate was decreased with the increasing of water vaper concentration regardless of sulfuric acid concentration. The sensitivity of electric current is improved for the narrower gap(1mm) of ring electrodes, but it rarely affects the SOx dew point measuring of different probes according to the change of cooling rate.

• 약학회지
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• 제25권4호
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• pp.137-143
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• 1981

In order to confirm the exact antipyretic component in the earthworm, etherial extract of American earthworm(Red Worm) was fractionated into five fractions by using silica gel column chromatography and thin layer chromatography. The fraction including free fatty acids was found to possess artipyretic response and standard arachidonic acid showed marked antipyretic response on typhoid vaccinated rabbits. Arachidonic acid was identified from the free fatty acid fraction of the earthworm by using gas liquid chromatography. Thus it was considered that the antipyretic activity of the free fatty acid may be due to the presence of arachidonic acid. Lipid-free earthworm powder was extracted with phosphate buffer (pH, 8.0, 0.1M) and all the proteins was salted out by ammonium sulfate. The crude precipitate was dialyzed and the impure proteins were eliminated at pH 5.4 and 4.6. The remaining protein solution was fractionated with various concentrations of acetone. The acetone fractions were identified by using S.D.S. polyacrylamide gel electrophoresis and disc gel electrophoresis. The precipitate at 85% acetone concentration and the remaining proteins in the supernatant did not exhibit the antipyretic activity.

• 한국환경과학회지
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• 제30권10호
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• pp.879-889
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• 2021

This study characterizes the volatile aromatic and metabolite components of domestic native Apocynum lancifolium blossom. The accurate characterization of fragrances collected from the blossom was carried out using gas chromatography-mass. A total of 70 chemical components were identified, including ketones of acetophenone (29.22%), phenylethyl alcohol (10.54%), methyl-benzenemethanol (8.43%), benzyl alcohol (7.97%), natural bicyclic sesquiterpene types of caryophyllene (6.08%), gurjunene (6.20%), humulene (1.90%), and ocimene (1.04%). Overall, the content of ketones, alcohols, and terpenes was higher than that of others. The major metabolite components were pentanoic acid, malic acid, fructofuranoside, quinic acid, tagatose, sorbose, galactose, inositol, galactaric acid, glucopyranoside, and octadecenoic acid.

• 한국식품저장유통학회지
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• 제30권5호
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• pp.758-769
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• 2023

The main aim of this study was to determine python fat's several physicochemical properties, including dimensions, color, structure, acid value (AV), saponification value (SV), density, and recovery efficiency. The optimum yield obtained was approximately 80.40% at 180℃ for 60 min with an AV of 0.3366 and SV of 179.56 mg KOH/g. Fatty acids, comprising oleic acid (72.462%), palmitic acid (26.243%), linolenic acid (0.835%), and myristic acid (0.459%), were identified using gas chromatography-mass spectrometry (GC-MS). The python fat had a very weak antioxidant capacity and almost no antibacterial ability with gram-positive (Staphylococcus aureus - ATCC 25923 and Bacillus cereus - ATCC 10876) and gram-negative (Escherichia coli - ATCC 25922 and Salmonella enterica - ATCC 35664) bacteria (used the paper disc diffusion method for antibiotic susceptibility testing). Moreover, python fat is considered to be very resistant to high temperatures.

• 한국식품위생안전성학회지
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• 제13권2호
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• pp.149-154
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• 1998

Vibrio cholerae non-O1 49균주와 V. Vibrio cholerae non-O1, V. mimicus, V. vulnificus와 V. parahaemolyticus의 균체 지방산(fatty acid methyl ester; FAME)을 gas liquid chromatogrphy로 분석하였다. 이들 분석자료를 통계학적으로 처리하여 Vibrio 종과 V. cholerae의 혈청형별 유연성을 비교 검토하였다. 검출된 지방산은 모두 41종이었고 분포량이 많은 것은 16:0, 16:1 cis 9, 18:1 trans 9/16/cis 11과 15:0 iso 2 OH/16:1 cis 9였다. 검출된 지방산 중에서 35종은 V. cholerae를 동정하는데 주요한 인자로 작용되었다 지방산분포를 UPGMA(비가중수리분석)으로 dendrogram을 작성한 결과 V. cholerae non-O!은 V. cholerae O1보다 V. choleare non-O1 중에서 O2, O5, O8, O10, O14, O27, O37, O39, O45와 O69의 총 10종류 혈청을 대상으로 지방산 조성에 의한 유사성을 검토한 결과 유사도가 92% 이상 수준에서 7개의 아종을 형성하여 혈청형과 지방산 조성간에는 유의할 만한 상관관계가 있었다. 따라서 V. cholerae non-O1의 동정 및 역학적인 조사시 지방산 분석은 유용하게 활용될수 있음을 알 수 있다.

• 한국식품영양과학회지
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• 제21권1호
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• pp.17-22
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• 1992

탈지된 산쑥(Artemisia montana Pampan)으로부터 물 추출물 및 에테르 추출물인 유리형 페놀산, 에스터형 및 불용성 페놀산을 추출하였다. 각 추출물들은 시판용 식용 대두유를 기질로 하여 $45^{\circ}C{\pm}1^{\circ}C$, 빛이 없는 항온기에서 32일간 저장하였으며, 매 4일 간격으로 과산화물가와 TBA치를 측정하였다. 물 추출물을 첨가한 시험구에서 항산화 효력이 모두 대조구보다 높게 나타나 BHA와 유사한 효력을 보였으나 BHT보다는 모두 항산화 효과가 낮게 나타났다. 에테르 추출물인 유리형, 에스터형 및 불용성 페놀산을 첨가한 시험구에서는 대조구보다 항산화 효력이 높았으며 유리형은 항산화 효력이 BHA와 유사했고 에스터형은 BHA보다 높고 BHT보다 낮게 나타난 반면 불용성 페놀산은 BHT보다 항산화 효력이 높게 나타남을 보여 주었다. 그리고 세가지 페놀산 추출물 중에서는 불용성 페놀산이 가장 강한 항산화 효과를 나타내었고 에스터형, 유리형 순이었다. Gas chromatography 로 부터 분리 동정된 페놀산은 catechol, vanillin, umbellinferone, protocatechuic acid, ferulic acid, caffeic acid였다. 이상의 결과들을 종합해 볼때 약용으로 사용하고 있는 산쑥은 caffeic acid, catechol, protocatechuic acid등의 항산화 효력이 강한 성분이 많이 함유되어 있으므로 식용대두유 기질에서 좋은 항산화 효력를 나타낸다고 생각된다.

• Journal of Animal Science and Technology
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• 제66권2호
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• pp.310-325
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• 2024

Glyconutrients help in the body's cell communication. Glyconutrients and synbiotics are promising options for improving immune function. Therefore, we hypothesized that combining synbiotics and glyconutrients will enhance pig nutrient utilization. 150 pigs (Landrace × Yorkshire × Duroc), initially weighing 58.85 ± 3.30 kg of live body weight (BW) were utilized to determine the effects of synbiotics-glyconutrients (SGN) on the pigs' performance, feed efficiency, gas emission, pork traits, and composition of fatty acids. The pigs were matched by BW and sex and chosen at random to 1 of 3 diet treatments: control = Basal diet; TRT1 = Basal diet + SGN 0.15%; TRT2 = Basal diet + SGN 0.30%%. The trials were conducted in two phases (weeks 1-5 and weeks 5-10). The average daily gain was increased in pigs fed a basal diet with SGN (p = 0.036) in weeks 5-10. However, the apparent total tract digestibility of dry matter, nitrogen, and gross energy did not differ among the treatments (p > 0.05). Dietary treatments had no effect on NH₃, H₂S, methyl mercaptans, acetic acids, and CO₂ emissions (p > 0.05). Improvement in drip loss on day 7 (p = 0.053) and tendency in the cooking loss were observed (p = 0.070) in a group fed basal diets and SGN at 0.30% inclusion level. The group supplemented with 0.30% of SGN had higher levels of palmitoleic acid (C16:1), margaric acid (C17:0), omega-3 fatty acid, omega-6 fatty acid, and ω-6: ω-3 ratio (p = 0.034, 0.020, 0.025, 0.007, and 0.003, respectively) in the fat of finishing pigs. Furthermore, group supplemented with 0.30% of SGN improved margaric acid (C17:0), linoleic acid (C18:2n6c), arachidic acid (C20:0), omega 6 fatty acid, omega-6 to omega-3 ratio, unsaturated fatty acid, and monounsaturated fatty acid (p = 0.037, 0.05, 0.0142, 0.036, 0.033, 0.020, and 0.045, respectively) in the lean tissues of finishing pigs compared to pigs fed with the control diets. In conclusion, the combination of probiotics, prebiotics, and glyconutrients led to higher average daily gain, improved the quality of pork, and more favorable fatty acid composition. Therefore, these results contributed to a better understanding of the potential of SGN combinations as a feed additive for pigs.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.377-382
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• 2004

This paper presents a novel optimization method for the air- and gas-supplying network comprised of several air compression systems and air and gas streams in an industrial chemical plant. The optimization is based on the hybrid model developed by Han and $Han^1$ for predicting the power consumption of a compression system. A constrained optimization problem was formulated to minimize the total electric power consumption of all the compression systems in the air- and gas-supplying network under various operating constraints and was solved using a successive quadratic optimization algorithm. The optimization approach was applied to an industrial terephthalic acid manufacturing plant to achieve about 10% reduction in the total electric power consumption under varying ambient conditions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.1073-1075
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• 2001

The nitrogen oxides, NO and NO2, abbreviated usually as NOx, emitted from combustion facilities such as power plants and automobiles are the typical air-pollutants causing acid rain and photochemical smog. In order to solve the NOx-related pollution problems effectively, we need efficient techniques to monitor NOx in the combustion exhausts and in environments. Development of solid-state electrochemical devices for detecting NOx is demonstrated based on various combination of solid electrolytes and auxiliary sensing materials. The object of this research is to develop various sensor performance for solid state amperometric sensor, and to test gas sensor performance manufactured. So we try to present a guidance for developing amperometric gas sensor. We concentrated on development of manufacturing process and performance test.

• 한국막학회:학술대회논문집
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• 한국막학회 1995년도 제3회 심포지움 (분리막 연구의 최신동향)
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• pp.21-22
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• 1995

Gas separation science and technology is among the most rapidly growing areas involving membrane-based processes. Nitrogen enrichment of air, hydrogen recovery from a broad array of stream types, and removal of acid gases from natural gases are typical of the applications in this field. Great progress has been made in the discovery of guidelines optimization of polymer structures with simultaneously high permeabilities and selectivities for these important gas pairs. The development of thin-skinned asymmetric hollow fibers have also provided structures with extremely high permeation fluxes. Especially in the case of O$_{2}$/N$_{2}$ separations, the rate of improvements in new polymeric materials for gas separations appears to be slowing to a halt. Evidence will be presented, however, that the practical tradeoff between membrane permeability and selectivity has not been reached.