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Title: High resolution gas volume change sensor

Abstract

Changes of gas quantity in a system can be measured either by measuring pressure changes or by measuring volume changes. As sensitive pressure sensors are readily available, pressure change is the commonly used technique. In many physiologic systems, however, buildup of pressure influences the gas exchange mechanisms, thus changing the gas quantity change rate. If one wants to study the gas flow in or out of a biological gas pocket, measurements need to be done at constant pressure. In this article we present a highly sensitive sensor for quantitative measurements of gas volume change at constant pressure. The sensor is based on optical detection of the movement of a droplet of fluid enclosed in a capillary. The device is easy to use and delivers gas volume data at a rate of more than 15 measurements/s and a resolution better than 0.06 {mu}l. At the onset of a gas quantity change the sensor shows a small pressure artifact of less than 15 Pa, and at constant change rates the pressure artifact is smaller than 10 Pa or 0.01% of ambient pressure.

Authors:
; ;  [1]
  1. Laboratory of Biomedical Physics, University of Antwerp, Groenenborgerlaan 171, Antwerp, Flanders B-2020 (Belgium)
Publication Date:
OSTI Identifier:
20953456
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 78; Journal Issue: 5; Other Information: DOI: 10.1063/1.2737778; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; BUILDUP; DETECTION; DROPLETS; EQUIPMENT; FLUIDS; GAS FLOW; RESOLUTION; SENSORS

Citation Formats

Dirckx, Joris J. J., Aernouts, Jef E. F., and Aerts, Johan R. M. High resolution gas volume change sensor. United States: N. p., 2007. Web. doi:10.1063/1.2737778.
Dirckx, Joris J. J., Aernouts, Jef E. F., & Aerts, Johan R. M. High resolution gas volume change sensor. United States. doi:10.1063/1.2737778.
Dirckx, Joris J. J., Aernouts, Jef E. F., and Aerts, Johan R. M. Tue . "High resolution gas volume change sensor". United States. doi:10.1063/1.2737778.
@article{osti_20953456,
title = {High resolution gas volume change sensor},
author = {Dirckx, Joris J. J. and Aernouts, Jef E. F. and Aerts, Johan R. M.},
abstractNote = {Changes of gas quantity in a system can be measured either by measuring pressure changes or by measuring volume changes. As sensitive pressure sensors are readily available, pressure change is the commonly used technique. In many physiologic systems, however, buildup of pressure influences the gas exchange mechanisms, thus changing the gas quantity change rate. If one wants to study the gas flow in or out of a biological gas pocket, measurements need to be done at constant pressure. In this article we present a highly sensitive sensor for quantitative measurements of gas volume change at constant pressure. The sensor is based on optical detection of the movement of a droplet of fluid enclosed in a capillary. The device is easy to use and delivers gas volume data at a rate of more than 15 measurements/s and a resolution better than 0.06 {mu}l. At the onset of a gas quantity change the sensor shows a small pressure artifact of less than 15 Pa, and at constant change rates the pressure artifact is smaller than 10 Pa or 0.01% of ambient pressure.},
doi = {10.1063/1.2737778},
journal = {Review of Scientific Instruments},
number = 5,
volume = 78,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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