• 제목/요약/키워드: boiling point

검색결과 329건 처리시간 0.023초

Studies on the Film forming Yeasts Isolated from Commercial Soy Sauce (제품(製品)간장에서 분리(分離)한 산막효모(産膜酵母)에 관(關)한 연구(硏究))

  • Chu, Young-Ha;Yu, Tai-Jong;Yu, Ju-Hyun
    • Korean Journal of Food Science and Technology
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    • 제7권2호
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    • pp.61-68
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    • 1975
  • This study was conducted (1) to isolate the film-forming yeast from the commercially available soy sauce, (2) to identify the state of soy sauce fermentation by the use of yeasts, (3) to confirm characteristics of yeasts. The result were as follows. 1. These yeast strains in the soy sauce fermentation test showed full fermentation of whole sugar content, reduction of the pure extract and relative reduction in total nitrogen. Soy sauce color was somehow faded to lower the stability of soy sauce. 2. In anti-fungal activity test butylparaben at a higher level 60 ppm., sodium propionate 2,400 ppm, sodium benzoate 800 ppm., menadion 165 ppm, showed their anti-fungal effect, while alcohol did not show the effect in the 3% additive group. 3. The optimum sodium chloride concentration for these strains in the 2% G.Y.P. medium was 5% and optimum temperature was $30^{\circ}C$. The extinction temperature was $62^{\circ}C$ for strain No-1 and No-3, and was $65^{\circ}C$ for No-2 and No-4. 4. The film-forming soy sauce turned out in the gas chromatogram to possess much flavor of low boiling point as compared with the standard. These flavors were considered due to flavor spoilage of the soy sauce. 5. These isolated yeasts were identified Saccharomyces rouxii (film-forming yeast) in the Lodder's taxanomic study.

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Proximate Compositions and Sensory Attributes of Soybean Sprouts with Recommended Soybean Cultivars (장려품종 나물콩으로 재배한 콩나물의 일반성분 및 관능적 특성)

  • Lee, Kyong-Ae;Kim, Yong-Ho;Kim, Hee-Sun
    • Journal of the East Asian Society of Dietary Life
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    • 제26권4호
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    • pp.325-333
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    • 2016
  • This study investigated the proximate compositions and sensory attributes of fresh and boiled soybean sprouts. The sensory attributes of cooked soybean sprouts (Kongnamulmuchim) were also assessed after boiling and seasoning. Proximate compositions were analyzed from the total sprout, cotyledon and hypocotyl without hair root. Soybean sprouts cultivated with four recommended soybean cultivars (Nokchae bean, Dawon bean, Seonam bean and Pungsannamul bean) in a lab and then used for analysis. Carbohydrate, protein, lipid and ash contents were lower, while moisture was lower, in the cotyledon than in the hypocotyl of fresh soybean sprouts, regardless of the bean type. Each soybean sprout showed different contents of chemical constituents in total sprout, cotyledon, and hypocotyl parts. Sensory attributes such as odor, flavor, and overall acceptability were evaluated. Each panels showed a response on a 9-point rating scale. The acceptability of fresh soybean sprouts was negatively correlated with beany and grassy tastes, but positively correlated with nutty and sweet tastes. The acceptability of boiled soybean sprouts was negatively correlated with beany and grassy flavors, and positively correlated with nutty odor and flavor. In addition, acceptability of cooked soybean sprouts (Kongnamulmuchim) was positively correlated with nutty and sweet flavors. The beany and grassy flavors limited acceptability of fresh soybean sprouts, whereas the prominence of nutty flavor might contribute to acceptance of boiled and cooked soybean sprouts.

Design of Naphtha Cracker Gas Splitter Process in Petlyuk Column (납사열분해 가스분리공정에서의 Petlyuk Column 설계)

  • Lee, Ju Yeong
    • Journal of the Korean Institute of Gas
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    • 제24권1호
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    • pp.17-22
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    • 2020
  • Light Naphtha is distillated from crude oil unit and separated into the methane, ethylene and propylene by boiling point difference in sequence. This separation is conducted using a series of binary-like columns. This separation method is known that the energy consumed in the reboiler is used to separate the heaviest components and most of this energy is discarded as vapor condensation in the overhead cooler. In this study, the first two columns of the separation process are replaced with the Petlyuk column. A structural design was exercised by the stage computation with ideal tray efficiency in equilibrium condition. Compared with the performance of a conventional system of 3-column model, The design outcome shows that the procedure is simple and efficient because the composition of the liquid component in the column tray was designed to be similar to the equilibrium distillation curve. The performance of the new process indicates that an energy saving of 12.1% is obtained and the cost savings of 44 million won per day based on gross domestic product is reduced under same total number of trays and the initial investment cost is saved.

Separation of $SF_6$ from $SF_6/N_2$ Mixtures Using Polymeric Membranes (고분자 분리막을 이용하여 $SF_6/N_2$ 혼합 기체에서 $SF_6$ 분리)

  • Ko, Young-deok;Lee, Hyung-Keun;Hong, Seong-Uk
    • Membrane Journal
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    • 제22권1호
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    • pp.72-76
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    • 2012
  • $SF_6$ has an extremely high global worming potential (GWP). Therefore, there has been an effort to reduce the use of $SF_6$ and its emission into atmosphere. One possible solution for minimizing the use of $SF_6$ in electrical equipments is utilization of gas mixtures such as $SF_6/N_2$. The $SF_6$ concentration in the gas mixture varies from 10 to 60%. However, when the apparatus is repaired or dismantled, we have to recover $SF_6$ from the gas mixture. Since the boiling point of $SF_6$is low (${\sim}-60^{\circ}C$), the liquefaction method is difficult to apply. One possible alternative is the membrane separation technology. In this study, we investigated the $SF_6$ and $N_2$ permeation properties of 5 polymeric membranes. For example, permeability of $N_2$ in BOPP membrane at $25^{\circ}C$was 0.19 barrer, whereas that of $SF_6$ was only 0.0012 barrer, resulting in the selectivity of 158. An upper bound for $SF_6/N_2$ gas pair was suggested for the first time with n = -1.33 and k = 160 (barrer).

Structural Analysis of Volatile Matters and Heavy Oil Fractions from Pyrolysis Fuel Oil by the Heat Treatment Temperature (열처리 온도에 따른 열분해 연료유 내 휘발유분 및 잔류 중질유분의 구조 분석)

  • An, Donghae;Kim, Kyung Hoon;Kim, Jong Gu;Lee, Young-Seak
    • Applied Chemistry for Engineering
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    • 제30권3호
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    • pp.297-302
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    • 2019
  • In order to investigate structural changes of the pyrolysis fuel oil (PFO), the volatile matters and heavy oil fractions were separated from PFO by heat treatment temperature. As a result of $^1H-NMR$ analysis of volatile matters, 1~2 ring aromatic compounds contained in the petroleum residue were mostly removed at a temperature before $340^{\circ}C$. Moreover, new peaks corresponding to aliphatic hydrocarbons were detected at the chemical shift of 2.0~2.4 ppm. It is attributed that the aliphatic hydrocarbon sidechain was cracked from the aromatic compound by the cracking reaction occurred at $320^{\circ}C$. The C/H mole ratio and aromaticity increased with increasing the heat treatment temperature. Therefore, from the structural analysis results of heavy oil fractions and volatile matters from PFO, the decomposition of the aliphatic sidechain by cracking reaction and the separation of volatile matters by boiling point of components were mostly affected structure changes of the PFO.

Characteristics of Low Temperature Desorption of Volatile Organic Compounds from Waste Activated Carbon in Cylindrical Cartridge (원통형 활성탄 카트리지 내 폐활성탄의 휘발성 유기화합물 저온 탈착 특성)

  • Kang, Sin-Wook;Lee, Seongwoo;Son, Doojeong;Han, Moonjo;Lee, Tae Ho;Hong, Sungoh
    • Clean Technology
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    • 제27권1호
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    • pp.79-84
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    • 2021
  • In this study, the waste activated carbon used in the painting process was filled into a cylindrical cartridge and the characteristics of desorption by low temperature gas were investigated. Adsorption and desorption experiments of toluene with activated carbon were conducted to determine the flow rate of desorption. In an experiment where desorption was performed while changing conditions at flow rates of 1, 2 and 4 ㎥ min-1, it was determined that 2 ㎥ min-1 was appropriate due to the high THC concentration and desorption time. In the early stage of the desorption of waste activated carbon, 2-butanone and MIBK (methyl isobutyl ketone) with a low boiling point were generated at a high rate in the gas component, and after that, the concentration of THC decreased and the BTX was desorbed at a high rate. The total calorific value of the gas component generated during the desorption of waste activated carbon was 316 kcal kg-1. From repeating the regeneration of waste activated carbon with toluene five times, it was observed that the iodine value and the specific surface area were relatively lower than that of new activated carbon. In the desorption experiment where two cylindrical cartridges were connected in series, the maximum THC concentration was about 470 ppm.

Comparison Analysis on Characteristics and Components of Various Waste Plastic Pyrolysis Oils by Vacuum Distillation Method (감압증류를 통해 분획된 폐플라스틱 열분해유의 특성평가와 구성성분 비교분석 연구)

  • Hwayeon Jeon;Cheol Hwan Jeon;Sung Joon Park;Jae Woo Lee;Jae-kon Kim
    • Clean Technology
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    • 제29권4호
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    • pp.262-271
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    • 2023
  • Globally, the amount of waste plastics has been occurring to environmental problems. As a result, it is necessary to research methods that utilize waste plastic pyrolysis oil (WPPO) produced by pyrolysis. One such method being studied is utilizing WPPO as a naphtha feedstock. In this study, five types of WPPO were analyzed to determine whether they can be used as raw materials for naphtha. Because of their wide boiling point range, the WPPOs were fractionated into light and heavy fractions through vacuum distillation, and the separation and purification techniques were analyzed using GC-VUV to determine the content of paraffin, olefin, and other compounds. All WPPOs showed high olefin content regardless of the source and fraction. Aromatic and paraffin content varied depending on the source, and oxygen and other compounds also varied significantly by source and fraction. In addition, the light fraction showed a carbon distribution similar to that of naphtha, whereas the heavy fraction showed a carbon distribution of C11 ~ C14. In conclusion, additional processes and raw material selection are required to utilize waste plastic pyrolysis oil as a raw material for naphtha.

Application of the Latest European Standard(EN 15522-2) for Marine Oil Spill Analysis: A Study on its Effectiveness in Analyzing Samples from Korean Incidents (해양 기름유출사고 분석을 위한 최신 유럽표준(EN 15522-2) 적용: 한국 사고 샘플 분석의 효율성에 관한 연구)

  • Youjeong Park;Duwon Lee;Heejin Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • 제30권1호
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    • pp.58-64
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    • 2024
  • Approximately 250 marine oil spill accidents have occurred in Korea, with profound impact on local communities and the environment. The restoration process necessitates significant resources and costs to return affected areas to their pre-accident state. In accordance with the polluter pays principle, compensation is demanded from polluter, as stipulated in both international conventions and national laws. Consequently, investigations are conducted to determine civil and criminal liability. As the importance of investigation actors in oil spill accidents increases, standards such as CEN 15522-2 and ASTM D 3248 are employed to determine the similarity between the spilled oil and the oil of the suspected ship. Among these standards, CEN 15522-2, the most actively used European standard, underwent its third revision and is now known as EN 15522-2, as of 2023. This study used EN 15522-2 to analyze samples from marine oil spill accidents that occurred in Korea. The results indicated that, considering the characteristics of domestic spills where light fuel oil spills account for more than 40%, the application of EN 15522-2, which includes low-boiling point substances such as Adamantanes, was confirmed to be highly effective.

Study on the viewpoint of the balance(平衡觀) on the 'Sanghan prescription(傷寒方) throughout the academic sources of 'Sang Han Lon' (상한론(傷寒論)의 학술연원(學術淵源)을 통(通)한 상한방(傷寒方)의 평형관 고찰)

  • Kim, Ji-hyung;Park, Sun-Dong
    • The Journal of Dong Guk Oriental Medicine
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    • 제4권
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    • pp.25-52
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    • 1995
  • 'Sang Han Lon' became the sources for treatment and prescription in the Oriental medicine. After that, for some 1800 years the various writings for studying in many ways more than 1000 books which many old sages really intended to inquire into and study the value of books. It is considered that it is the result which the old sages tried to grope for many-sided directions in order to understand 'Sang Han Lon'. In this study, I tried to inquire into prescription and its relevant medicinal substances, that is to say, the crystalization of the physiology, pathology and treating method on the basis of the academic sources of his thoughts. The method to approach is "from what basis of thought system was 'Sang Han Lon' derived first of all?" Secondly, how was the thought system, which became the basis of 'Sang Han Lon', applied to concretely? I studied on the basis of the above important two problems. It is well known to everybody that 'Sang Han Lon' succeeded to the tradition of Naekyung(內經) as well as Cwuyek(周易, Chinese classic on divination). Besides, I inquired into and arrived at conclusion as follows that how the viewpoint on the balance(平衡觀), which was one of the common point between. Cwuyek(周易) and medical science in case of the 'Sanghan prescription'(傷寒方), was applied to concretely. 1. In naming, it is considered that from the same interconnection which the common point with Cwuyek(周易) was the same as obtaining the imigination(取象), the imagination was obtained and was named. 2. In case of being concerned in the gastro-intestinal track, namely, the core of the balance and harmony with the balance and harmony being emphasized, '理中'(It implies 'taking care of gasstro-intestinal track')" and '建中'(It implies 'establishing of gastro-intestinal track'), that is to say, '中'(It implies 'taking care of' & 'establishing of gastro-intestinal track') was emphasized much more. 3. In case of treatment taking advantage of three kinds of medicine in draught, powder and pills in the prescription, while treating during adjusting the slowness and fastness, I maintained the harmony not to damage the righteousness(正氣). 4. In case of the prescription, when exhaling(發散), astringing(收斂), loosing bowels, protecting the gastro-intestinal track and vomitting, he used the medicinal sustances in order to protect the gastro-intestinal track and treated not to damage the righteousness. 5. Especially, in case of the prescription in order to adjust the negative and positive principle of inside-outside(素囊陰陽), he composed of medicinal substances relevant to hot, cold, spicy and sour(寒熱辛酸) in conformity with the prescription and I paid much more attention to the one-sided treatment. Considering the various prescriptions, it is regarded that the adjusting prescription is kept its balance. 6. In the way of processing the medicinal substances in order to change effect of medicine in conformity with the reenactment, he tried to plan the balance of '一升一降' with the decrease of RHEI RADIX ET RHIZOMA(大黃) and increase of wine. 7. In boiling the medicine, he boiled the composed medicine in the time sequence for the purpose of adjusting the slowness and fastness and adapted to harmony of the negative and positive principle(陰陽調和) on the essence function(體峻用純). 8. In taking medicine, he tried to reduce the time of taking the medicine in case of being boiled slowly and tried to increase the dosage and eventually he planned the balance of one time slowness and one time fastness. As I inquired into the above result, a few steps for protecting method to boil the relevant medicinal substances, how to take the medicine and how to process the composed medicinal substances in order to change the effect of medicine can make the human body, which the disease penetrate into, go forward to the righteousness(正氣) and what is much beter, it is considered that this protecting method can be a carefully considerable one in order to protect the righteousness and can subdue the disease, not to damage the gastro-intestinal track and there can exist the viewpoint of balance(平衡觀) on its core.

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Mass Production Process for Flour Noodles Containing Perilla Leaves and Their Antioxidant Effects (깻잎 첨가 국수 대량 생산 공정 개발 및 이의 항산화 효과)

  • Hyun, Hyo-Eun;Lee, Eun-Hwa;Noh, Jeong-Sook;Song, Yeong-Ok
    • Journal of the Korean Society of Food Science and Nutrition
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    • 제40권12호
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    • pp.1688-1693
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    • 2011
  • This study was evaluated mass production processes for flour noodles containing perilla leaf (FNPL) and to examine the antioxidant properties of FNPL. The processes for perilla leaf preparation before dough making were the main focus. The sensory evaluation was used as a tool to determine the optimal conditions for each step in the process. The appearance, taste, flavor, texture and overall acceptability were evaluated using a 9 point scale sensory evaluation. Eight minutes blanching of perilla leaf in boiling water (1:30, w/v) was found to be a suitable time to remove the unpleasant leaf flavor remaining in the final noodle product when fresh perilla leaf was used. The appearance, taste, texture and overall acceptability of FNPL were significantly different from FNPLs prepared with other blanching times. The appearance of FNPL containing 40% (w/v) perilla leaf homogenates was the best. In the dough making process, additional water was not required when 6 portions of 40% perilla leaf homogenate were added to 10 portions of flour, suggesting that the water adding step in the dough preparation process can be skipped. The antioxidant activity of FNPL was expressed as the radical scavenging activity. The DPPH ($IC_{50}$; 0.56 mg/mL), super oxide radical ($IC_{50}$; 9.53 mg/mL) and hydroxy radical scavenging activities ($IC_{50}$; 169.2 ${\mu}g$/mL) of FNPL were increased 19.6 (p<0.001), 1.4 (p<0.01) and 17.8 fold, respectively, compared to those for flour noodle (p<0.001). In conclusion, perilla leaf added to noodles at a final concentration of 19% (w/w) can increase the sensory and antioxidant properties of flour noodles.