• Title/Summary/Keyword: optimum storage time

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Studies on Microbial Penicillin Amidase (II) Characteristics and the Reactor Performance of Whole Cell Immobilized Penicillin Amidase of Escherichia coli (미생물 페니실린 아미다제에 관한 연구 (II) E. coli의 균체 고정화 페니실린 아미다제의 특성 및 반응조에 관한 연구)

  • Seong, Baik-Lin;Kim, Bong-Hee;Mheen, Tae-Iek;Moon H. Han
    • Microbiology and Biotechnology Letters
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    • v.9 no.1
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    • pp.35-44
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    • 1981
  • Whole cell penicillin amidase of Escherichia coli was immobilized by entrapment in gelatin followed by extrusion and crosslinking with glutaraldehyde. The immobilized engyme preparation demonstrated the recovery yield of activity up to 70% and good stability during storage and operation. The half life of activity decay during the operation was estimated to be about 50 days. The optimum pH and temperature for both of immobilized and soluble enzyme are 8.5 and 5$0^{\circ}C$, respectively. No significant change was demonstrated in the effect of pH and temperature, but the increase in heat stability at high temperature was observed in the case of the immobilized enzyme. It was found that the plug flow reactor could be operated favorably since the pH drop along the column path due to tile reaction product was minimized by employing substrate solution with moderate buffer strength. The optimal condition of reactor operation was discussed with regard to the effect of substrate concentration and the residence time on the conversion efficiency and productivity.

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Practical Application of Sn-3.0Ag-0.5Cu Lead Free Solder in Electronic Production

  • Chae Kyu-Sang;Min Jae-Sang;Kim Ik-Joo;Cho Il-Je
    • Journal of the Microelectronics and Packaging Society
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    • v.12 no.1 s.34
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    • pp.65-71
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    • 2005
  • At present, Electronic industries push ahead to eliminate the Pb(Lead) -a hazardous material-from all products. Especially, we have performed to select the optimum standard composition of lead free alloy for the application to products for about 3 years from 2000. These days, we have the chance for applying to the mass-production. This project constructed the system for applying the lead free solders on consumer electronic products, which is one of the major products of the LG Electronics. To select the lead free solders with corresponding to the product features, we have passed through the test and applied with Sn-3.0Ag-0.5Cu alloy system to our products, and for the application to the high melting temperature composition, we secured the thermal resistance of the many parts and substrate and optimized the processing conditions. We have operated the temperature cycling test and the high temperature storage test under the standards to confirm the reliability of the products. On these samples, we considered the consequence of our decision by the operating test. For the long life time of the product, we have operated the temperature cycling test at $-45^{\circ}C\;-\;+125^{\circ}C$, 1 cycle/hour, 1000 cycles. Also we have tested the tin whisker growth about lead free plating on lead finish. We have analyzed with the SEM, EDS and any other equipment for confirming the failure mode at the joint and the tin whisker growth on lead free finish.

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A study of baking properties depending on soybean flour and calcium added (발효 대두분 및 칼슘을 첨가한 혼합소맥분의 제빵적성에 관한 연구)

  • 김현혜;이정훈;윤미숙
    • Culinary science and hospitality research
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    • v.7 no.3
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    • pp.263-273
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    • 2001
  • This study was to investigate the effect of 5~20% soybean flout(SBF) and/or 0.5~5% calcium on the quality of bread. pH of bread was increased with increasing an amount of SBF and calcium. pH of bread was higher than that of dough. The scores of specific volume and sensory evaluation for the bread quality were shown higher and increased its relative volume in the group of added both of 5~15%, SBF and 0.5~2%, calcium Endothermic peak for a thermal property of bread was increased with increasing the storage time of bread. The bread staling was progressed rapidly in control and calcium added groups only. with increasing an amount of SBF, L values of bread was decreased, but a and b values were increased. However, L, a and b values were shown no difference in the group of calcium added only. Therefore, the optimum blending ratios of SBF and calcium for the quality of bread were 5~10%, SBF and 0.5~1% calcium, respectively.

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Factors affecting the vertical distribution of Betula platyphylla var. japonica and Betula ermanii on Mt. Neko in Nagano Prefecture, Japan

  • Jiro, Otsubo;Shigeru, Mariko;Ichiroku, Hayashi
    • Journal of Ecology and Environment
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    • v.33 no.2
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    • pp.121-131
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    • 2010
  • Betula platyphylla var. japonica and Betula ermanii segregate vertically at an elevation of approximately 1,850 m on Mt. Neko in Nagano Prefecture, Japan. B. platyphylla var. japonica and B. ermanii were the dominant species below and above this altitude, at which the mean-annual and growing-season air temperatures were $4^{\circ}C$ and $14.1^{\circ}C$, respectively. Based on a modification of Kira's warmth index which employs cumulative temperature represented as $^{\circ}C$ day, leaf unfolding in both species was observed to be initiated at $58^{\circ}C$ day and $169^{\circ}C$ day, respectively. In 1996, leaf unfolding was initiated on 18 May in B. platyphylla var. japonica (+/-6 days) and on 5 June in B. ermanii (+/-8 days), shortly after the last frost which occurred on 5 May 1995 above 1,850 m; below this elevation there was no risk of frost at the time. At elevations above 1,850 m, the unfolded leaves of B. platyphylla were damaged by late frost, while B. ermanii escaped injury because the leaves were still protected by winter buds. The optimum temperature for seed germination in both B. platyphylla and B. ermanii was $30^{\circ}C$. Temperature alternation from 10 to $30^{\circ}C$ and moist storage of seeds at $4^{\circ}C$ (stratification) prior to incubation increased germination rates in both species. The seedlings of B. ermanii had a greater survival rates than those of B. platyphylla var. japonica when planted above 1,850 m. Comparisons of the timing of leaf unfolding and the latest frost at a site appeared to be the main factors affecting the vertical distribution of these species.

A Study on the Calcium Ion Extraction for PCC Production (PCC 제조를 위한 칼슘이온 추출 조건에 관한 연구)

  • Lee, Ye-Hwan;Lee, Sang Hyun;Hwang, In-Hyuck;Choi, Sung-Yeol;Lee, Sang Moon;Kim, Sung Su
    • Applied Chemistry for Engineering
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    • v.29 no.1
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    • pp.43-48
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    • 2018
  • In this study, we performed various extraction condition experiments such as types and concentrations of extractants, amounts of extraction sources, pretreatment processes, to optimize the calcium ion extraction for precipitated calcium carbonate (PCC) production. CaO was used as a calcium extraction source, The extraction amount of calcium ions and the particle size of CaO were determined by ICP and SEM results. As a result, 100% calcium ion was extracted when 2 M hydrochloric acid was used as an extractant, and the optimum amount of the extraction source was 6 g. On the other hand, it was confirmed that the reaction time, reaction temperature, particle milling and heat treatment process had no significant effect on the calcium ion extraction amount.

A Study on the pattern of energy consumption of apartment in winter with Automatic Meter Reading Systems (원격검침시스템을 활용한 공동주택의 동절기 에너지 소비패턴 분석)

  • Shin, Juho;Kim, Hongseok;Lee, Donghwan;Park, Seunghee
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.3
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    • pp.1225-1234
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    • 2013
  • According to the importance of greenhouse gas emissions, it grows day by day, the goverment is promoting to prepare the specific policy implementation to enhance building energy-saving design standars as the development agenda. In this study, the statistical analysis was performed by Descriptive statistics, Regression analysis, and Hypothesis testing to collect to generate and storage energy usage data in real time to settle parameter setting to affect energy consumption under energy-guzzling apartment not single building. This study is expected to be utilized as the basis for the optimum energy-saving design of the future of the building or facility energy costs rise and the demand for energy-efficient and stable management.

Similar Trajectory Store Scheme for Efficient Store of Vehicle Historical Data (효율적인 차량 이력 데이터 저장을 위한 유사 궤적 저장 기법)

  • Kwak Ho-Young;Han Kyoung-Bok
    • The Journal of the Korea Contents Association
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    • v.6 no.1
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    • pp.114-125
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    • 2006
  • Since wireless Internet services and small mobile communication devices come into wide use as well as the use of GPS is rapidly growing, researches on moving object, whose location information shifts sequently in accordance with time interval, are being carried out actively. Especially, the researches on vehicle moving object are applied to Advanced traveler information system, vehicle tracking system, and distribution transport system. These systems are very useful in searching previous positions, predicted future positions, the optimum course, and the shortest course of a vehicle by managing historical data of the vehicle movement. In addition, vehicle historical data are used for distribution transport plan and vehicle allocation. Vehicle historical data are stored at regular intervals, which can have a pattern. For example, a vehicle going repeatedly around a specific section follows a route very similar to another. If historical data of the vehicle with a repeated route course are stored at regular intervals, many redundant data occur, which result in much waste of storage. Therefore this thesis suggest a vehicle historical data store scheme for vehicles with a repeated route course using similar trajectory which efficiently store vehicle historical data.

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Properties of an Extracellular 5-Fluorocytosine Deaminase (세포외 5-Fluorocytosine Deaminase의 특성)

  • Yeeh, Yeehn;Jun, Hong-Ki;Yoon, Yong-Kyun
    • Microbiology and Biotechnology Letters
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    • v.20 no.2
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    • pp.150-155
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    • 1992
  • - Some properties of an extracellular cytosine deaminase excreted from an isolate from soil samples were examined after 20~80%' ammonium sulfate fractionation. The enzyme catalyzed the conversion of cytosine and 5-fluorocytosine into uracil and 5-fluorouracil by substrate specificity, respectively. The optimum temperature and storage time on the stability of the enzvme preparation were below $50^{\circ}C$ keeping above 90% of the residual activity and near 4 days keeping above 80% of the residual one in Tris-HCI buffer. The maximum activity was also obtained at 8.0 in pH and 37'C in temperature. The pHs and temperatures for enzyme activity ranged from 8.0~8.5 and from 37~$45^{\circ}C$. respectively. The presence of $Ag^-,Hg^{2-}, Zn^{2-}, Cu^{2-}, Sn^{2-}, \; or\; Pb^{2-}$ in the reaction mixture resulted in the marked inhibition in enzyme activity, but 1 mM of $K^+, Fe^[3+}, Mg^{2+}, \; or \; Na^+$. slightly increased the activity. The enzyme preparation was heavily affected by most of inhibitors tested such as 1 mM of EIITA, NaCN and pentachlorophenol, and completely inactivated by p-CMB and TCA of 1 mM, or 10 mM.

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A Study on Development and Utilization of Automatic Parking Survey System (자동주차조사 시스템 개발 및 활용에 관한 연구)

  • Lee, Young Woo;Kwon, Hyuck Jun
    • Journal of Korean Society of Transportation
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    • v.32 no.5
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    • pp.452-461
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    • 2014
  • Conventional parking survey has been usually performed by a person, which has a lot of problems such as decreased mobility, data input error, longer time and expensiveness. Therefore, this study attempted to develop an automatic parking survey method using lately commercialized equipments that were highly efficient imagery interpretation equipments, GPS, and infrared lighting fixtures. In addition, this study developed a parking analysis software that enables to modify and save data, and analyze survey data by the automatic parking survey method. When parking survey is conducted using automatic parking survey method, surveying accuracy is influenced by the running speed of a surveying vehicle, the photographing angle of an imagery interpretation equipment, the gap between parking vehicles and the distance of a surveying vehicle to parking vehicles. Therefore, this study drew optimum conditions by testing on each items for accuracy improvement, and developed a parking analysis software for systematic storage and management of parking survey data, supporting the parking analysis and output the parking analysis result.

Development of Soybean Sprouter Using Principle of Siphoning (싸이폰원리를 이용한 콩나물 자동재배기 개발)

  • Kim, Joong-Man;Choi, Yong-Bae;Yang, Dong-Kun
    • Korean Journal of Food Science and Technology
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    • v.29 no.3
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    • pp.460-463
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    • 1997
  • One of the major problems in automation of soybean sprouter is watering method. This study was conducted solve this problem. The soybean sprouter consisted of three parts: water-receiving chamber with siphon, water spraying bowl and sprout cultivating bowl. It functions as automatic-watering without manpower and electric power, and is not noisy and has duration. Watering interval, watering time and amount could be controlled by regulation of dropping times/min from a tap. Chlorine contained in tap water is naturally decreased during its (water) storage in the water receiving chamber. Among three types of sprouter (siphon type, wet paper type and water pump type) the siphon type can be used at $25{\sim}30^{\circ}C$ that is the optimum temperature for soybean sprout.

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