• Title/Summary/Keyword: $O_2$ Consumption

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Optimal Conditions for Chitinase Production by Serratia marcescens

  • Cha, Jin-Myeong;Cheong, Kyung-Hoon;Cha, Wol-Suk;Choi, Du-Bok;Roh, Sung-Hee;Kim, Sun-Il
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.9 no.4
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    • pp.297-302
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    • 2004
  • A chitinase-producing bacterium was isolated from seashore mud around Beobseongpo in Chunmam province through the use of a selective enrichment culture. The best chitinase producing strain was isolated and identified as Serratia marcescens KY from its characteristics. For effective production of chitinase, optimum pH, temperature, and agitation speed were investigated in flask cultures. The optimum pH using Serratia marcescens KY was between pH 6 and 7 and the chitinase produced was 37.9 unit/mL. On the other hand, the optimal pH of the Serratia marcescens ATCC 27117 was 7.5, and the produced amount of chitinase was 35.2 unit/mL. The optimal temperature for chitinase production for Serratia marcescens KY and Serratia marcescens ATCC 27117 was $30^{\circ}$. The cell growth pattern at different temperature was almost identical to the chitinase production. To investigate the optimal shaking speed under optimal culture, speeds were varied in the range of 0∼300 rpm. The maximum production of chitinase was carried at 200 rpm although the cell growth was the highest at 150 rpm. It indicates that oxygen adjustment is required for the maximum chitinase production. Using optimal conditions, batch cultures for comparing Serratia marcescens KY and Serratia marcescens ATCC 27117 were carried out in a 5 L fermentor. The oxygen consumption was increased with the increase of culture. Especially, at 120 h of culture Serratia marcescens KY and Serratia marcescens ATCC 27117 produced 38.3 unit/mL, and 33.5 unit/mL, respectively.

Electrodeposition of Silicon in Ionic Liquid of [bmpy]$Tf_2N$

  • Park, Je-Sik;Lee, Cheol-Gyeong
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.10a
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    • pp.30.1-30.1
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    • 2011
  • Silicon is one of useful materials in various industry such as semiconductor, solar cell, and secondary battery. The metallic silicon produces generally melting process for ingot type or chemical vapor deposition (CVD) for thin film type. However, these methods have disadvantages of high cost, complicated process, and consumption of much energy. Electrodeposition has been known as a powerful synthesis method for obtaining metallic species by relatively simple operation with current and voltage control. Unfortunately, the electrodeposition of the silicon is impossible in aqueous electrolyte solution due to its low oxidation-reduction equilibrium potential. Ionic liquids are simply defined as ionic melts with a melting point below $100^{\circ}C$. Characteristics of the ionic liquids are high ionic conductivities, low vapour pressures, chemical stability, and wide electrochemical windows. The ionic liquids enable the electrochemically active elements, such as silicon, titanium, and aluminum, to be reduced to their metallic states without vigorous hydrogen gas evolution. In this study, the electrodeposion of silicon has been investigated in ionic liquid of 1-butyl-3-methylpyrolidinium bis (trifluoromethylsulfonyl) imide ([bmpy]$Tf_2N$) saturated with $SiCl_4$ at room temperature. Also, the effect of electrode materials on the electrodeposition and morphological characteristics of the silicon electrodeposited were analyzed The silicon electrodeposited on gold substrate was composed of the metallic Si with single crystalline size between 100~200nm. The silicon content by XPS analysis was detected in 31.3 wt% and the others were oxygen, gold, and carbon. The oxygen was detected much in edge area of th electrode due to $SiO_2$ from a partial oxidation of the metallic Si.

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A study on the vehicle fire property using the large scale calorimeter (대형칼로리미터를 이용한 차량 화재 특성에 관한 연구)

  • Yoo, Yong-Ho;Kim, Heung-Youl;Shin, Hyun-Jun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.9 no.4
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    • pp.343-349
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    • 2007
  • The reduced scale fire test provides basic data but it is not enough to analysis real fire problem directly because there is no exact analogy theory between a real fire and the reduced scale model. Therefore we have developed the large scale calorimeter in order to the real scale fire test. This advanced large scale calorimeter used for physical properties such as a heat release rate, based upon consumption of $O_2$ method. Using this large scale calorimeter, we cameo out the real scale vehicle fire test in order to evaluation for heat release rate. We obtained the calculated result for HRR $2.3{\sim}3.4\;MW$ and this result is very similar to the PIARC candidate HRR. It is approve that this facility has the reliability and it is capable of applying to the advance fire research in the future.

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EFFECT OF SILT AND SALINITY ON THE MORTALITY OF MERETRIX LUSORIA $(R\ddot{O}DING)$ (이질과 염분이 백합의 폐사에 미치는 영향)

  • CHANG Sun-duck;CHIN Pyung;SUNG Byung-oun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.9 no.1
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    • pp.69-73
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    • 1976
  • Mortality of clam, Meretrix lusoria was measured during the experimental cultures in different sediments compositions and in different salinities of sea water. Experimental groups maintained in silt and clay showed significant mortality, while those treated in sand and in sand-silt showed little mortality. In the groups cultured in silt and clay, young groups of approximately 2.5cm in shell length were subjected to early and high mortality (approximately eighty-five per cent in foully-one days). The larger the shell size was, the later and the lower the mortality occurred. In different salinity, the groups maintained in silt and clay showed different mortalities. It is observed that the survival rate of the shell in the sea water of low salinity was higher than that in the high salinity water. Oxygen consumption of isolated gill tissue showed a little difference between the groups maintained in silt and clay and those in sand (the control-group). Consequently, it may be stated that the mortality results mainly from the deposition of silt and clay, although the survival rate of Meretrix lusoria depends also on water temperature, salinity, dissolved oxygen, body size ana other factors.

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Comparison of Textural Properties in Various Types of Brown Rice (품종별 현미밥의 조직감 특성 비교)

  • Yoon, Mi-Ra;Lee, Jeom-Sig;Lee, Jeong-Heui;Kwak, Jieun;Chun, Areum;Won, Yong-Jae;Kim, Bo-Kyeong
    • The Korean Journal of Food And Nutrition
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    • v.27 no.2
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    • pp.294-301
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    • 2014
  • Rice (Oryza sativa L.) is one of the most important staple foods in Korea and the consumption of brown rice is increasing annually. The objective of this study is to investigate the physicochemical, hydration and textural properties related to eating quality of cooked brown rice by using glutinous, semi-glutinous, four non-glutinous and four colored varieties. The moisture, protein and total dietary fiber contents of brown rice are shown in the range of 11.1~12.6%, 6.6~8.7% and 6.28~12.40%, respectively. The amount of water uptakes for brown rice during the hydration has shown significant differences. The glutinous variety of Boseogchal indicate the highest water absorption levels by reaching $0.38gH_2O/g$. The hardness of hydration for Seolgaeng is distinctively lower than those of the other brown rice varieties. According to the textural characteristics of cooked brown rice when using the Tensipresser, the hardness of Boseogchal, Baegjinju and Seolgaeng all exhibit the lowest values out of ten varieties and the highest levels of adhesiveness.

Analyses of Formulas in "Key to Therapeutics of Children's Diseases (小兒藥證直訣)" (소아약증직결(小兒藥證直訣)의 처방분석(處方分析))

  • Cho, Hyun-Jin;Park, Ki-Jeong;Park, Sun-Dong
    • Herbal Formula Science
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    • v.19 no.2
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    • pp.119-133
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    • 2011
  • Objectives : This study aimed to reveal the characteristics of formulas in "Key to Therapeutics of Children's Diseases" by analysis of crude drugs that constitute formulas. Methods : To analyze the formulas, We classified the formulas to presenting symptom classification. And within that categories, the crude drugs in formulas were diagrammatized. Results : After those analyses, we brought a conclusion as like these. 1. The formulas classified into some categories that include chronic consumption disease, parasitization, digestive system disease, febricity, infectious disease, respiratory disease, skin disease, infirmity and etc. 2. We analyzed the characteristic of formulas by categorization of crude drug combination. In this way, we recognized that Qian Yi(錢乙) frequently used cold crude drugs unlike the trend of S$\grave{o}$ng(宋) dynasty doctors. 3. The prescription that described in "Key to Therapeutics of Children's Diseases" can be found in "Treasured Mirror of Eastern Medicine(東醫寶鑑)" and the other books on posterity. Conclusions : Through these researches, we verified that Qian Yi affect cold herbal and mineral drugs. This tendency of Qian Yi have an effect on the Nourish yin school. And several decades of formulas of "Key to Therapeutics of Children's Diseases" contain in part of pediatrics on "Treasured Mirror of Eastern Medicine". We reconfirmed that Qian Yi affected profound influence on the development of pediatrics and Nourish yin school.

Microwave hybrid sintering of NTC themistor (마이크로파 하이브리드 소결법에 의한 NTC 서미스터의 제조)

  • 최영락;안진용;안주삼;백동규;최승철
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.8 no.3
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    • pp.508-512
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    • 1998
  • The NTC thermistors were sintered by using microwave hybrid heating method at $1100^{\circ}C$~$1300^{\circ}C$ and those electrical properties were investigated. The obtained $B_{25^{\circ}C/85^{\circ}C}$ values from temperature dependence of electrical resisitivity were around 3100~3200 K which were almost the same values as conventionally sintered ones. Compared with conventional sintering process, this process could complete whole sintering process within 20 minutes. This the processing time and energy consumption could be reduced through this rapid heating by using microwave hybrid heating.t there were showed only two peaks, glycolide melting peak and lower molecular weight melting peak without lauryl alcohol. Conversion increased slowly with the reaction time up to 50 minutes, and then gave a sudden increase above that. The reaction time to disappear in glycolide melting peak during polymerization was shortened with the increase of lauryl alcohol content. Zero-shear viscosity of polyglycolic acid decreased with the increase of free acid content in glycolide.ssional energy and bending hysteresis increased. \circled3 Surface characteristics such as friction coefficient and thickness variation of highly shrinkage fabrics became relatively roughened state. \circled4 Since stiffened and roughened characteristics of highly shrinkage fabrics, drapabilities of them were significantly lowered. Additionally thermal insulation property of high shrinkage fabric was higher than that of low shrinkage fabric due to bulky and thickened feature. From the results, it is considered that the silk fabrics with high filling shrinkage have the good bulkiness and heat keeping properties and thus they have the suitable characteristics for high quality men's and women's formal garments.

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People Participation Towards Opisthorchis viverrini Prevention and Control in Chaiyaphum Province, Northeastern Thailand

  • Phongsiripapat, Rutjirapat;Chimplee, Kanokporn;Rujirakul, Ratana;Kaewpitoon, Soraya;Keawpitoon, Natthawut
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.1
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    • pp.177-181
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    • 2016
  • This cross-sectional descriptive and qualitative study was aimed to study the people participation and their approaches toward the human carcinogenic liver fluke, Opisthorchis viverrini, prevention and control in Ban Chaun sub-district administrative organization (BCSAO) and Bamnet Narong sub-district municipality (BNSM), Bamnet Narong district, Chaiyaphum Province, Thailand between June 2013 and February 2014. Participants were purposive selected, included chiefs of sub-district administrative organizations, sub-district municipalities, sub-district health promotion hospitals (SHPHs), heads of village, and a further sample was selected with a multi-stage random sampling for public health volunteers, and villagers. The pre-designed questionnaire contained items for individualized status and the participatory steps of sharing ideas, decision-making, and planning, procession, evaluation, and mutual benefit, for the project O. viverrini prevention and control (POPC). In-depth interviews were used for collection of need approaches to POPC. With 375 participants who completed the questionnaire, it was found that people had a high level regarding to participate in the POPC, particularly in the process stage ($\bar{X}=3.78$, S.D. = 0.56), but the lowest level was found in sharing ideas, decision making, and planning step ($\bar{X}=3.65$, S.D. = 0.63). By comparison, participant status and organization did not significantly differ with people participation. In each step, Ban Chaun sub-district had a high level of participation in the step of sharing ideas, decision making, and planning toward POPC, more than Bamnet Narong sub-district municipality (t=2.20, p=0.028). Approaches for POPC in Ban Chaun sub-district and Bamnet Narong sub-district municipality included requirements for budget support, annual campaigns for liver fluke prevention and control, campaign promotion, risk group observation, home visiting, community rules regarding reducing raw fish consumption in their communities, and a professional public health officer for working in their communities, BCSAO, BNSM, and SHPH, for O. viverrini prevention and control. This study indicates that people realize that eradication of the liver fluke needs a continuous people participation for O. viverrini prevention and control in their communities.

Investigation of Microbial Contamination Levels of Leafy Greens and Its Distributing Conditions at Different Time - Focused on Perilla leaf and Lettuce - (시기별 엽채류의 미생물 오염도와 유통 조건 조사 - 들깻잎과 상추를 중심으로 -)

  • Kim, Won-Il;Jung, Hyang-Mi;Kim, Se-Ri;Park, Kyeong-Hun;Kim, Byung-Seok;Yun, Jong-Chul;Ryu, Kyoung-Yul
    • Journal of Food Hygiene and Safety
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    • v.27 no.3
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    • pp.277-284
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    • 2012
  • The objective of this study was to investigate and evaluate microbial contamination levels of leafy greens (perilla leaf and lettuce) and its distributing conditions at different seasons (Feb, May, Aug, and Nov of the year 2011) in order to provide insight into any potential health hazards associated with consumption of these commodities. Leafy greens were collected from a farm located in Geumsan, Chungnam and wholesale markets (WM) and traditional markets (TM) located in Suwon. At the same time, temperature and relative humidity fluctuations experienced by the leafy greens during distribution from the farm to the distribution center were measured by a data logger. The contamination levels of perilla leaf and lettuce were determined by analyzing total plate count. Coliform groups, Bacillus cereus, Escherichia coli, Escherichia coli O157:H7, Salmonella spp., Listeria monocytogenes and Staphylococcus aureus were determined. The contamination levels of total aerobic bacteria, coliform groups and B. cereus in both vegetables sampled during May and August found to be higher than those sampled during February and November. E. coli O157:H7, Salmonella spp., L. monocytogenes were not detected in the vegetables analyzed in this study. There were no significant trends between samples at WM and TM in the contamination levels. Relative humidity of vegetables distributed from the farm to the distribution center showed over 90% during distribution regardless of measured seasons. In the case of background microflora on leafy greens, the density was significantly increased at 20, 30 and $37^{\circ}C$ during storage of 24h. E. coli O157:H7 and B. cereus inoculated on the leaves also showed similar increases in the storage tests. The microbial contamination levels determined in this study may be used as the fundamental data for microbial risk assessment.

Variation of organic matter and rice yield in in continuous forage use of barley and rice straw

  • Ku, Bon-Il;Hwang, Jae-Bok;Choi, In-Bea;Bae, Hui-Su;Kim, Hag-Sin;Park, Tae-Seon;Park, Hong-Kyu;Lee, Geon-Hwi
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.184-184
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    • 2017
  • Organic matter is very important and essential factor to maintain productivity of paddy field. But as meat consumption and the demand of grain increase, the demand of forage also increased gradually in Korea. So the amount of organic matter in paddy field have been declined gradually by the reduction of return of rice straw for the forage use for cattle. There is not enough alternative resources for forage, we guess this trend of organic matter decline in paddy field would continue for the time being in Korea. So this study was performed to confirm the variation of organic matter and change of rice yield to select suitable rice cultivars which yield reduction is small in condition of organic matter decrease in paddy field. To confirm the change of rice growth and yield in condition of organic matter decrease in paddy field, we transplanted 10 rice cultivars which yield reduction are small in low fertilizer condition. We transplanted it Buan where double cropping of winter barley continues several years on June 10. Planting density were $70plants/3.3m^2$ Fertilizer amount was $N-P_2O_5-K_2O=9-4.5-5.7kg/10a$ and fertilizer split application of nitrogen was basal-tillering stage-panicle initiation = 50-20-30%. And in the other cultivation management, we observed rice standard culture of NICS. In paddy field where withdraw straws of barley and rice, the organic matter content showed tendency to decrease as the years go on. During rice cultivation season, organic matter decreased little by little, but it increased again after rice harvest season. Rice yield was more in order of Sodami, Chunghaejinmi and Saenuri. We judge that there is an advantage in rice yield of rice cultivars which have later heading date because of suitable ripening temperature. Although Sobibyeo and Shindongjinbyeo showed high yield, head rice yield decreased severely owing to chalky and cracked rice.

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