• Title/Summary/Keyword: Mist1

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The Transcription Factor Mist1 Regulates the Cellular Polarity in Mouse Pancreatic Acinar Cells

  • Yang, Yu-Mi;Lee, Syng-Ill;Shin, Dong-Min
    • International Journal of Oral Biology
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    • v.37 no.1
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    • pp.37-41
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    • 2012
  • Pancreatic acinar cells exhibit a polarity that is characterized by the localization of secretory granules at the apical membrane. However, the factors that regulate cellular polarity in these cells are not well understood. In this study, we investigated the effect of Mist1, a basic helix-loop-helix transcription factor, on the cellular architecture of pancreatic acinar cells. Mist1-null mice displayed secretory granules that were diffuse throughout the pancreatic acinar cells, from the apical to basolateral membranes, whereas Mist1 heterozygote mice showed apical localization of secretory granules. Deletion of the Mist1 gene decreased the expression of type 3 inositol 1,4,5-triphosphate receptors ($IP_3R$) but did not affect apical localization and expression of $IP_3R2$. Mist1-null mice also displayed an increase in luminal areas and an increase in the expression of zymogen granules in pancreatic acinar cells. These results suggest that Mist1 plays a critical role in polar localization of cellular organelles and in maintaining cellular architecture in mouse pancreatic acinar cells.

Optimal Conditions for Mist Sensing and Removal in Automobile (자동차 내부의 김서림 감지 및 제거를 위한 최적의 조건)

  • You, Do-Hyun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.5
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    • pp.763-769
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    • 2012
  • For mist sensing, temperature-humidity sensor is attached on six positions of front glass and rearview mirror in automobile. Bottom-left side of front glass is the best position where mist is sensing. For mist removal, air conditioner is turned on intensity 1, 3 and is set the temperature at 17[$^{\circ}C$], 25[$^{\circ}C$]. And heater is turned on intensity 1, 3 and is set the temperature at 25[$^{\circ}C$], 32[$^{\circ}C$]. The best condition which mist is removed is temperature at 17[$^{\circ}C$] and intensity 3 of air conditioner mode. At this condition, total average value of humidity output voltage difference is 0.561[V]. Also, air conditioner mode is effective than heater mode for mist sensing and removal.

Determining Factors to Enhanced Oil Mist Filter Efficiency Using CFD Modeling (CFD모델링을 통한 오일 미스트필터효율 향상 결정요소에 관한 연구)

  • Shin, Hee-Jae
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.20 no.10
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    • pp.119-127
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    • 2021
  • Small drops in gas cause some problems for downstream equipments such as turbine, compressor and etc. In some cases, we are obliged to remove hazardous liquid mist from gas. In order to remove water or other liquids from the gas, there are some equipments like mesh mist eliminator and vane-plate mist eliminator. oil mist filter is a kind of liquid eliminator equipments used to remove the liquid with 1-10um droplet diameter from the gas. In this paper is determine the factors affecting the oil mist filter efficiency using CFD. length and angle of the filter were considered and the results and compare the results of the efficiency tests, showed error of less than 3%. optimum filter can remove more than 87.3% between 1 and 10um of oil mist.

The Effects of Water Mist on the Compartment Fire

  • Ryou, Hong-Sun;Kim, Sung-Chan
    • International Journal of Air-Conditioning and Refrigeration
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    • v.12 no.1
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    • pp.30-36
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    • 2004
  • The present study investigates the fire suppression characteristics using a water mist fire suppression system. Numerical simulations of fire suppression with water mist are performed with considering the interaction of fire plume and water spray. The predicted temperature fields of smoke layer are compared with those of measured data. Numerical results agree with the experimental results within $10^{\circ}C$ in the case without water mist. In the case of fire suppression with water mist, numerical results do not predict well for temperature field in the gradual cooling region after water mist injection. But the predicted results of initial fire suppression are in good agreement with those of measured data. The reason for the discrepancy between predicted and measured data is due to the poor combustion modeling during the injection of water mist. More elaborate models for numerical simulation are required for better predictions of the fire suppression characteristics using water mist.

A study on the Water Mist Fire Suppression Performance (미세 물 분무 소화 성능에 관한 연구)

  • 김봉환;김용판;문철진;홍철현;이형욱
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2002.05a
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    • pp.61-65
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    • 2002
  • The present study was numerically and experimentally performed to investigate the fire suppression performance of water mist spray subjected to thermal radiation in closed space. Downward-directed water mist sprays to interact with an under kerosine pool fire were investigated in test facility. The mass mean diameters of water mist droplet were measured by PMAS under various flow conditions. The developed water mist spray nozzle was satisfied to the criteria of NFPA 750, Class 1. The mechanism of the fire suppression by water mist was concluded to be cooling of the fire surface which lead to suppressed of fuel evaporation. It was proved that the water mist spray system under lower pressures could be applied to underground fire protection system.

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A Study on the Performance of Water Mist Spray Fire Protection System (미세물분무 소화성능에 관한 연구)

  • 김봉환;김용판;문철진;홍철현;이형욱;최현호
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.7
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    • pp.572-578
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    • 2003
  • The present study was numerically and experimentally performed to investigate the fire suppression performance of water mist spray subjected to thermal radiation in closed space. Downward-directed water mist sprays to interact with an under kerosine pool fire were investigated in test facility The mass mean diameters of water mist droplet were measured by PMAS under various flow conditions. The developed water mist spray nozzle was satisfied to the criteria of NFPA 750, Class 1. The mechanism of the fire suppression by water mist was attributed to the cooling of the fire surface which lead to suppressed of fuel evaporation. It was proved that the water mist spray system under lower pressures could be applied to underground fire protection system.

Performance Evaluation on Water-mist Extinguishing System of Railway Vehicles (철도차량 미분무수 소화설비 성능 평가)

  • Park, Won-Hee;Eum, Pu-Reun-Byul;Yoon, Kyung-Beom;Lee, Duck-Hee
    • The KSFM Journal of Fluid Machinery
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    • v.17 no.1
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    • pp.22-27
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    • 2014
  • The test system for the performance of the water-mist extinguishing system in the railway vehicle is equipped and the details of the system are introduced. The three scenarios using different fire sources and performance criteria for the water-mist systems on railway vehicles are also introduced. Three different type of the nozzle at same operating pressure are evaluated. Amount of water-mist distribution is measured by many baskets on the bottom of the test room. Temperature on the ceil and the tree of the test room is measured during the tests that are used for the judgement of the performance on the water-mist extinguishing system.

A Study on Spray Characteristics of Water Mist Nozzle with Mid-low Pressure for Fire Suppression (화재용 중저압 물분무 노즐의 분무특성에 관한 연구)

  • 김성찬;유홍선;박현태;방기영
    • Journal of the Korean Society of Safety
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    • v.18 no.1
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    • pp.28-32
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    • 2003
  • The present study investigates the spray characteristics of water mist nozzle with mid-low pressure for fire suppression. The examined nozzle types are swirl and spiral nozzle. The result shows that K factor of water mist nozzle is much smaller than those of general sprinkler. Spray angle of spiral nozzle is largest and more than $150^{\circ}$. SMD(Sauter Mean Diameter) of water mist nozzles is ranged between 100 and 200$\mu\textrm{m}$through measuring by image processing method. The spray pattern of spiral nozzle represent that water flux of first stream is 2 times larger than that of second stream. This study will contribute better understandings of the water-mist spray characteristics and useful daia for developing the water-mist nozzles.

Spray Flow Characteristics of Twin-fluid Water Mist Nozzle for Fire Suppression (2유체 미세 물분무 소화노즐의 분무유동 특성)

  • Kim, Bong-Hwan;Choi, Hyo-Sung;Kim, Dong-Keon
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.3
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    • pp.60-66
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    • 2011
  • In the present investigation, experimental studies were conducted on the fire suppression performance of twin-fluid water mist spray which is subjected to thermal radiation in a closed space. Downward-directed water-mist sprays, interacting with an under kerosene pool fire, were investigated in a test facility. The mass mean diameter of water-mist droplets were measured by PMAS under various flow conditions. The developed twin-fluid water mit spray nozzle satisfied the criteria of NFPA 750, Class 1. The mechanism of fire suppression by fine water mist was concluded to be the cooling of the fire surface which leads to the suppression of fuel evaporation. It was proved that the automatic twin-fluid water mist spray system under lower pressures could be applied to an industrial facilities.

Extinguishing of Oil Fire by Water Mist Suppression System Using Compressed Inert Gas (불활성 압축가스를 이용한 미세물분무 소화시스템의 유류화재 소화특성)

  • Shin, Chang-Sub;Jeon, Go-Un;Kim, Ki-Whan
    • Journal of the Korean Society of Safety
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    • v.25 no.6
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    • pp.109-114
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    • 2010
  • Water mist fire suppression system is environmental system and needs a flange pump to jet water. In this research, high pressure Nitrogen cylinder is used as a pressurizing source instead of flange pump, and also we tried to find the possibility of using compressed Nitrogen as a fire suppression agent. As a result, it was possible to design water mist fire suppression system with Nitrogen cylinder and suppress oil fire effectively. With DK1.58 nozzle, the optimum Nitrogen pressure was 80bar and the pressure was stable during water mist spray. However, jet of Nitrogen was not effective fire suppression agent when it was dually used with water mist because water mist has blown away, and it is efficient way to use compressed Nitrogen as a pressurizing source only.