• 제목/요약/키워드: in-situ experiments

검색결과 334건 처리시간 0.024초

An experimental procedure for evaluating the consolidation state of marine clay deposits using shear wave velocity

  • Chang, Ilhan;Kwon, Tae-Hyuk;Cho, Gye-Chun
    • Smart Structures and Systems
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    • 제7권4호
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    • pp.289-302
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    • 2011
  • In marine clay deposits, naturally formed or artificially reclaimed, the evaluation and monitoring of the consolidation process has been a critical issue in civil engineering practices due to the time frame required for completing the consolidation process, which range from several days to several years. While complementing the conventional iconographic method suggested by Casagrande and recently developed in-situ techniques that measure the shear wave, this study suggests an alternative experimental procedure that can be used to evaluate the consolidation state of marine clay deposits using the shear wave velocity. A laboratory consolidation testing apparatus was implemented with bimorph-type piezoelectric bender elements to determine the effective stress-shear wave velocity (${\sigma}^{\prime}-V_s$) relationship with the marine clays of interest. The in-situ consolidation state was then evaluated by comparing the in-situ shear wave velocity data with the effective stress-shear wave velocity relationships obtained from laboratory experiments. The suggested methodology was applied and verified at three different sites in South Korea, i.e., a foreshore site in Incheon, a submarine deposit in Busan, and an estuary delta deposit in Busan. It is found that the shear wave-based experimental procedure presented in this paper can be effectively and reliably used to evaluate the consolidation state of marine clay deposits.

Effect of Several Adsorbents on The Gastrointestinal Absorption of Paraquat

  • Machijima, Hiraku;Nakamura, Hiroyuki;Hatanaka, Tomomi;Sugibayashi, Kenji;Morimoto, Yasunori
    • Archives of Pharmacal Research
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    • 제17권5호
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    • pp.287-293
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    • 1994
  • The effect of several adsorbents on paraquat poisohing was investigated (1) by measuring the saturatd amount of the poison adhered on the adsorbents in vitro and (2) by assaying the blood level of paraquat in the rat in in situ intestinal absorption experiments. Activated charcoal powder, natural aluminum silifonate) were used as adorbents. The steady-state blood level of paraquat in its absorption experiment with the cationic exchange resins was markedly lower than those without the resins or with other adsorbents. A good relationship was achieved between the calculated AUC or adsorptioin rate (in situ) and the saturated adsorption amount (in vitro). The rank order of the effect was sodium polystyene sulfonate > calcium polystyene sulfonate>natural aluminum silicate>activated charcoal powder. The effect of sodium polystyrene sulfonate after intestinal washing with physiological saline ws also measured, and a synergistic effect (marked decrease in blood paraquat level0 was found as compared with the intestinal washing alone. The simultaneous use of G.I. weshing and powerful adsorbent was scientifically proven to be most benefical.

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회분식 발효에서의 전기투석에 의한 젖산의 동시분리 (In situ Separation of Lactic Acid by Electrodialysis in Batch Culture)

  • 이은교;장용근;장호남;김인호
    • 한국미생물·생명공학회지
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    • 제23권5호
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    • pp.609-616
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    • 1995
  • Effects of lactate concentration, temperature, counter ions, pH as well as voltage (current) in batch electrodialysis (ED) experiments with a 3-compartment unit were investigated. The applied voltage was found to be the most critical factor as expected. The electrodialysis rate increased with the lactate concentration of the source solution. The amount of lactate transferred was limited by the lactate concentration difference between cathode and permeate compartments. The electrodialysis rate did not heavily depend on temperature change. The electrodialysis rate of NH$_{4}$-lactate was faster than that of Na-lactate and both lactates showed the highest electrodialysis rate at a pH of 4.0. A little amount of non-ionic glucose diffused through the anionic membrane to the permeate compartment. To test the effectiveness of the in situ recovery of lactic acid from fermentation broth by ED, three cases of batch culture were carried out; pH control only, ED only, and pH control and ED. The case with both pH control and ED was more efficient than that with pH control only in the aspects of productivity and product yield.

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Field Experiments Using In Situ Bioremediation to Treat Trichloroethylene (TCE)-Contaminated Groundwater

  • Goltz, Mark N.;Gandhi, Rahul K.;Gorelick, Steven M.;Hopkins, Gary D.;McCarty, Perry L.
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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    • pp.261-266
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    • 2001
  • Three innovative technologies to remediate trichloroethylene (TCE) in situ were (or currently are being) evaluated at a TCE-contaminated groundwater site at Edwards Air Force Base (AFB), California. The three technologies all make use of groundwater recirculation to obviate the need to pump contaminated groundwater to the surface fer treatment. The first technology, which implements aerobic cometabolic bioremediation to destroy TCE in situ, successfully reduced dissolved TCE concentrations from above 1 mg/L to 20-30 $\mu\textrm{g}$/L. The second technology, in-well vapor stripping (IWVS), is capable of treating dissolved TCE at concentrations in the tens to hundreds of mg/L. Finally, the third technology, bioenhanced in-well vapor stripping (BEHIVS): is a combination of the first two technologies, and is designed to reduce very high levels of TCE (tens to hundreds of mg/L) to concentrations that meet regulatory requirements 5 $\mu\textrm{g}$/L). Results of field evaluations of tile first two technologies are presented, and the design of the BEHIVS system. as well as model predictions of BEHIVS performance and the current status of the technology field evaluation. is discussed.

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Development of a Time-selective Self-triggering Water Sampler and Its Application to In-situ Calibration of a Turbidity Sensor

  • Jin, Jae-Youll;Hwang, Keun-Choon;Park, Jin-Soon;Yum, Ki-Dai;Oh, Jae-Kyung
    • Journal of the korean society of oceanography
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    • 제34권4호
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    • pp.200-206
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    • 1999
  • Seawater sampling is the primary task for the study of the marine environmental parameters that require shipboard or laboratory experiments for their analyses, and is also required for the calibration of some instruments for in situ measurement. A new automatic bottle (AUTTLE) is developed for seawater sampling at any desired time and water depth by self-triggering. Both any type of single or assembled mooring for 15 days and manual actuation by using a remote messenger as existing instantaneous single point water samplers are possible. Its sampling capacity and the resolution of time setting are 2 liters and 1 second, respectively. The result of a field experiment with an optical backscattering sensor (OBS) and a total of 14 AUTTLES for the in situ calibration of the OBS shows that the AUTTLE must improve our understanding on the behavior of the sand/mud mixtures in the environments with high waves and strong tides. The AUTTLE will serve as a valuable instrument in the various fields of oceanography, especially where synchronized seawater sampling at several sites is required and/or the information in storm period is important.

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Temperature Calibration of a Specimen-heating Holder for Transmission Electron Microscopy

  • Kim, Tae-Hoon;Bae, Jee-Hwan;Lee, Jae-Wook;Shin, Keesam;Lee, Joon-Hwan;Kim, Mi-Yang;Yang, Cheol-Woong
    • Applied Microscopy
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    • 제45권2호
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    • pp.95-100
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    • 2015
  • The in-situ heating transmission electron microscopy experiment allows us to observe the time- and temperature-dependent dynamic processes in nanoscale materials by examining the same specimen. The temperature, which is a major experimental parameter, must be measured accurately during in-situ heating experiments. Therefore, calibrating the thermocouple readout of the heating holder prior to the experiment is essential. The calibration can be performed using reference materials whose phase-transformation (melting, oxidation, reduction, etc.) temperatures are well-established. In this study, the calibration experiment was performed with four reference materials, i.e., pure Sn, Al-95 wt%Zn eutectic alloy, NiO/carbon nanotube composite, and pure Al, and the calibration curve and formula were obtained. The thermocouple readout of the holder used in this study provided a reliable temperature value with a relative error of <4%.

In situ 나일론백 그리고 모바일백 방법을 이용한 국내 부존사료자원의 반추가축용 사료 가치 평가 (Evaluation of non-conventional feeds for ruminants using in situ nylon bag and the mobile bag technique)

  • 백열창;최혁
    • 한국산학기술학회논문지
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    • 제18권7호
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    • pp.73-83
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    • 2017
  • 본 연구는 반추동물 사료로서 한국에서 생산된 부존사료자원 15종의 화학적 조성, 소화율 그리고 에너지 가를 평가하기 위하여 실시하였다. 반추위 그리고 십이지장 캐뉼라가 장착된 거세한우 3두(평균체중 $520{\pm}20.20kg$)를 개별 계류식우사에 공시한 후 14일의 순치기간과 3일간의 시험기간을 두었다. 실험 방법으로는 화학조성 분석법, in situ 나일론백과 모바일백 방법을 이용하였다. 사료 내 화학적 조성을 분석한 결과, 엿밥, 깻묵, 장유박 및 두유박의 조단백질 함량은 30% 이상이었다. In situ 나일론백을 이용한 사료의 분해 특성을 분석한 결과, 비트펄프, 맥주박, 커피박, 엿밥, 수수겨, 임자박, 라면박 및 두유박의 반추위 미분해 단백질 함량은 50% 이상이었다. In situ 모바일백을 이용한 사료 내 가소화 영양소총량(TDN)의 분석은 비트펄프, 맥주박, 막걸리박, 수수겨, 깻묵, 라면박, 미강, 장유박, 비지, 두유박 및 밀기울이 50% 이상인 것으로 관찰되었다. 요약하자면, 상기 부존사료자원은 배합사료 또는 조사료를 대체할 수 있는 훌륭한 사료자원으로서의 높은 잠재적 가치를 가지고 있음을 시사하고 있다. 따라서 본 연구에서 얻은 부존사료자원의 화학적 조성, 소화율 및 에너지 가를 반추동물 섬유질배합사료 제조를 위한 기초 자료로 활용하고 이를 통해 사료효율 향상, 사료비용 절감 및 환경오염 감소에 기여하고자 한다.

TTF-1 Expression in PACAP-expressing Retinal Ganglion Cells

  • Son, Young June;Park, Jeong Woo;Lee, Byung Ju
    • Molecules and Cells
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    • 제23권2호
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    • pp.215-219
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    • 2007
  • In mammals light input resets the central clock of the suprachiasmatic nucleus by inducing secretion of pituitary adenylate cyclase-activating polypeptide (PACAP) from retinal ganglion cells (RGCs). We previously showed that thyroid transcription factor 1 (TTF-1), a homeodomain-containing transcription factor, specifically regulates PACAP gene expression in the rat hypothalamus. In the present study we examined the expression of TTF-1 in PACAP-synthesizing retinal cells. Fluorescence in situ hybridization (FISH) showed that it is abundantly expressed in RGCs of the superior region of the retina, but in only a small subset of RGCs in the inferior region. Double FISH experiments revealed that TTF-1 is exclusively expressed in PACAP-producing RGCs. These results suggest that TTF-1 plays a regulatory role in PACAP-expressing retinal ganglion cells.

낙동강 하구역 사주 주변에서의 퇴적물질의 유압거동 해석 (The Analysis of Inflowing Sediments Behavior around the Sandbar in Nakdong River Estuary)

  • 김경희;이인철
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2004년도 학술대회지
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    • pp.133-136
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    • 2004
  • In-situ collection experiments were performed to analyze inflowing sedilnents behavior as a basic study of topographical change in Nakdong River Estuary. Sediment rate and bed load flux ranged from 0.0004 to $0.472\;g/cm^2/day\;and\;0.0005\~1.7579\;g/cm^2/day$, respectively. The settling velocity of suspended particulate matter was estimated in tire range of $0.339\~1.010\;cm/sec$, The grain size analysis shows that surface sediments in backside of sandbar and bed load in front of dike have a similar grain size distribution. It is considered that the source of surface sediments in backside of sandbar were flowed in from Nakdong River. In order to verify the characteristics of inflowing sediments behavior, detailed surveys around Nakdong River Estuary need to be carried out, continuously.

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불포화 토양내에서 가스상 오존 이동특성에 대한 Multiphase liquids의 영향

  • 정해룡;최희철
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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    • pp.124-127
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    • 2003
  • Laboratory scale experiments on in-situ ozonation were carried out to delineate the effects of liquid phases, such as soil water and nonaqeous phase liquid (NAPL) on the transport of gaseous ozone in unsaturated soil. Soil water enhanced the transport of ozone due to water film effect, which prevent direct reaction between soil particles and gaseous ozone, and increased water content reduced the breakthrough time of ozone because of increased average linear velocity of ozone and decreased air-water interface area. Diesel fuel as NAPL also played a similar role with water film, so the breakthrough time of ozone in diesel-contaminated soil was significantly reduced compared with uncontaminated soil. However, ozone breakthrough time was retarded with increased diesel concentration, because of high reactivity of diesel fuel with ozone. In multiphase liquid system of unsaturated soil, the ozone transport was mainly Influenced by nonwetting fluid, diesel fuel in this study.

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