• 제목/요약/키워드: Lab scale

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고등학교 화학II 수업에 적용한 Small-Scale Chemistry 실험의 효과 (The Effects of Small-Scale Chemistry Laboratoty Programs in High School Chemistry II Class)

  • 홍지혜;박종윤
    • 한국과학교육학회지
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    • 제27권4호
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    • pp.318-327
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    • 2007
  • 본 연구의 목적은 고등학교 화학II 교과에서 Small Scale Chemistry(SSC)를 적용한 수업이 학생들의 과학 탐구 능력과 과학관련 태도에 미치는 효과를 알아보는데 있다. 연구 대상은 인문계 고등학교 3학년 학생 112명이며, 실험 집단과 비교 집단으로 나누었다. 화학II 교과서의 기존 실험을 대치할 수 있는 SSC 실험을 7개 선정하여 이를 실험 집단에 적용하고, 비교 집단에는 교과서에 제시된 기존 실험을 적용하였다. 연구 결과 두 집단 간에 과학 탐구 능력의 향상에는 유의미한 차이가 있었으나, 과학관련 태도의 향상에는 유의미한 차이가 없었다. 세부 분석 결과 과학 탐구 능력의 차이는 기초 탐구 능력의 차이에 의한 것으로 나타났다. 실험 집단 학생들은 SSC 실험이 기존 실험에 비해 많은 장점(예를 들면, 개별 실험, 실험과 이론의 동시 학습, 짧은 실험 시간, 안전성, 친환경성 등)이 있음을 인식하고 있었다. 이러한 결과는 고등학교 화학 과목에 SSC 실험을 적용할 가치가 있음을 나타내며 현 교과서의 기존 실험을 대치할 수 있는 다양한 SSC 실험을 개발하여 보급할 필요가 있음을 시사한다.

실험실 규모 입상 혐기성 암모늄 산화 연속회분식 반응조 내의 신종 사상균 동시 농화 배양에 관한 연구 (Simultaneous Enrichment of Novel Filamentous-Like Bacterial Population in Lab-Scale Granular Anaerobic Ammonia Oxidation (Anammox) Sequencing Batch Reactor)

  • 박홍근
    • 한국물환경학회지
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    • 제29권3호
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    • pp.377-382
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    • 2013
  • Enriching anammox bacteria (AMX) in a lab-scale granular sequencing batch reactor using local digester centrate, we observed the significant enrichment of the filamentous-like bacterial population. These bacteria were revealed as novel bacterial species (termed CHL) belonging to Chlorobi/Bacteroidetes phyla via Denaturing Gradient Gel Electrophoresis (DGGE). Further, niche differentiation of AMX and CHL quantification was observed in granule and filament biomass, suggesting AMX was dominant in the granule and CHL was dominant in the filament. Therefore, it was confirmed the structural role of CHL was indeed to aid the granule formation of the AMX. In parallel, the physiological role of CHL was suspected to degrade biopolymers in the digester centrate using nitrate as an electron acceptor.

담수조건에 따른 토양 내 중금속 용출특성과 안정화공법의 효과 검토 (An Investigation on the Effect of Stabilization Methods and Leaching characteristics of Heavy Metals in Paddy Soils contaminated by Heavy Metal under Submerged Condition)

  • 유찬;윤성욱;강신일;진혜근
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 추계 학술발표회
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    • pp.1201-1212
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    • 2010
  • In order to investigate on the effect of stabilization methods for rice paddies contaminated by heavy metals, a series of lab-scale model test was carried out by applying the characteristics of submerged Paddy soil. To perform the lab-scale model test, columns were made by acrylic with the dimension of diameter=10cm, thickness=0.5cm and were filled with soils which was contaminated were mixed with stabilization agents(lime stone 5% and steel refining slag 5% respectively). To manipulate the reduction condition, soils in the columns were submerged with distilled water. And then soil water and subsurface water in each column were sampled in the regular term and analysed the various physical and chemical properties.

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Vision-based technique for bolt-loosening detection in wind turbine tower

  • Park, Jae-Hyung;Huynh, Thanh-Canh;Choi, Sang-Hoon;Kim, Jeong-Tae
    • Wind and Structures
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    • 제21권6호
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    • pp.709-726
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    • 2015
  • In this study, a novel vision-based bolt-loosening monitoring technique is proposed for bolted joints connecting tubular steel segments of the wind turbine tower (WTT) structure. Firstly, a bolt-loosening detection algorithm based on image processing techniques is developed. The algorithm consists of five steps: image acquisition, segmentation of each nut, line detection of each nut, nut angle estimation, and bolt-loosening detection. Secondly, experimental tests are conducted on a lab-scale bolted joint model under various bolt-loosening scenarios. The bolted joint model, which is consisted of a ring flange and 32 sets of bolt and nut, is used for simulating the real bolted joint connecting steel tower segments in the WTT. Finally, the feasibility of the proposed vision-based technique is evaluated by bolt-loosening monitoring in the lab-scale bolted joint model.

실험실규모 순환유동층에서 RDF와 RPF의 연소 특성에 관한 연구 (Combustion of RDF and RPF in a Lab-Scale Circulating Fluidized Bed)

  • 이재성;이응록;안민하;박상욱;신동훈;황정호
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2004년도 제28회 KOSCO SYMPOSIUM 논문집
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    • pp.173-179
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    • 2004
  • Combustion of refuse derived fuel(RDF) and refuse plastic fuel (RPF) was carried out in a lab-scale circulating fluidized bed. Experiment was investigated cold flow visualization. RDF was made by C & tech and RPF was made by KRS. The results include distribution of temperature in the combustion chamber, and concentrations of flue gas such as $O_2$, $CO_2$, CO, $NO_x$ and HCs Micro G.C(gas chromatograph) was employed to find out concentration of He Temperature distribution was different when RDF and RPF were burnt respectably. As air ratio became increased, $CO_2$, CO, and total of HCs emissions were decreased. According to the number of carbon atom of HCs, HC were classified as five kinds of HC.

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Performance of a Foam Fractionator in a Lab-scale Seawater Recirculating Aquaculture System

  • Peng Lei;Jo Jae-Yoon
    • Fisheries and Aquatic Sciences
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    • 제6권4호
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    • pp.187-193
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    • 2003
  • The performance of a foam fractionator to remove TAN, $NO_2,\;NO_3$, TSS, protein, and $PO_4-P$ at different superficial air velocities and foam overflow heights was evaluated in a lab-scale seawater recirculating system for culture of Korean rockfish (Sebastes schlegeli). The foam overflow rates increased with the increase of superficial air velocities, but decreased with the increase of foam overflow heights. Concentrations of all the water quality variables in the foam condensates increased with the increase of foam overflow height, but decreased with the increase of superficial air velocities. TSS, protein, and phosphate enrichment factors were within the range of 6.4-39.4, 1.6-7.3 and 1.2-3.9, respectively. Low values of TAN, $NO_2,\;and\;NO_3$ enrichment factors were obtained and they indicate that foam fractionation is rot an effective way to remove dissolved inorganic nitrogen. The calculated maximum daily removal values for TSS and protein were 10.9 and 1.4g, respectively.

Characterization of Microbial Community in Biological Wastewater Treatment System Using Respiratory Quinone Profiles

  • Lim Byung-Ran;Ahn Kyu-Hong;Lee Yonghun
    • 한국미생물학회:학술대회논문집
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    • 한국미생물학회 2003년도 International Meeting of the Microbiological Society of Korea
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    • pp.111-114
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    • 2003
  • The dynamics of microbial community structure of the various domestic wastewater treatment processes were examined using a novel approach of quinone profiles. The compositions of microbial quinone of 5 sites fer plant and lab-scale activated sludge were analyzed. More than 14 kinds of quinones were observed in the activated sludges tested in this study. The microbial community structure of the plant activated sludge processes a little differed from that of the lab-scale submerged MBR systems. The dominant quinones were UQ-8, UQ-10 followed $MK-8(H_4)$, MK-7 and MK-6. The molar ratio of ubiquinones to menaquinones (UQ/MK) changed from 0.81 to 1.9, indicating that aerobic bacteria dominated the microbial community of the activated sludge examined. The microbial diversity of the activated sludges calculated from the all quinone compositions was 9.5-11.9 and the microbial equability of the activated sludges was 0.64-0.79.

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입자와 액적간의 정전기적 응집을 통한 미세입자의 효율적인 제어 (Effective Control of fine Particles Using an Electrostatic Coagulation Between Particle and Water Droplet)

  • 이명화;김상범;황유성;김종호;김경수
    • 한국분무공학회지
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    • 제11권2호
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    • pp.98-104
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    • 2006
  • A charged droplet scrubber was introduced to remove visible smokes generated in many industrial facilities. Lab-scale and field tests were conducted in this study. The system consists of a corona discharger to effectively charge the fine particles, fellowed by an electrostatic chamber to promote coagulation between charged fine particles and oppositely charged droplets and a demister to remove resultant particles. Overall collection efficiency, 98.4% was obtained from a lab-scale test, when a high voltage was applied to an ionizer and a charged droplet scrubber. Field tests also show the high collection efficiencies, 93.5% with one stage and 99.4% with two stage system. This system can be used to increase the collection efficiency of the conventional air pollution control devices to satisfy the national emission standard.

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생물학적 하수처리시스템에 적용된 Proportional, Integral 및 P-I 조절 시스템에 대한 비교 (Comparison of Proportional, Integral, and P-I Control Systems in Biological Wastewater Treatment Plants)

  • 김성표
    • 한국물환경학회지
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    • 제21권4호
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    • pp.410-415
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    • 2005
  • The main purpose of this study is to evaluate the characteristics of three sets of traditional control methods (proportional, integral, and proportional - integral controls) through lab-scale biological reactor experiments. An increase in proportional gain ($K_c$) resulted in reduced dissolved oxygen (DO) offset under proportional control. An increase in integral time ($T_i$) resulted in a slower response in DO concentration with less oscillation, but took longer to get to the set point. P-I control showed more stable and efficient control of DO and airflow rates compared to either proportional control or integral control. Developed P-I control system was successfully applied to lab-scale Sequencing Batch Reactor (SBR) for treating industrial wastewater with high organic strength.

Lab-Scale Biosparging Study to Remediate Diesel-Contaminated Soil and Groundwater : the effect of air injection rate and pattern

  • 조수형;이시진;권순열;장순웅
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 추계학술발표회
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    • pp.462-466
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    • 2003
  • This study was conducted to examine the potential of biosparging process in removing diesel contaminated soil and groundwater. The experiment was carried out lab-scale biosparging reactor and the biodegradation rate of diesel was evaluated as function of air injection rate and pattern. When renter was operated as air injection rate of 1000$m\ell$/min and pulsed air injection(15min pulse, 15min downtime), DO concentration in the renter was higher than another operating condition. The evidence for biodegradation of diesel was the $O_2$ utilization and $CO_2$ product following the cessation of sparging. Especially, air injection rate of 2000$m\ell$/min and pulsed air injection(15min pulse, 15min downtime) enhanced the diesel biodegradation during the operating. After 120day, the biodegradation rate of diesel was decreased as the lack of carbon source.

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