আপেক্ষিক গুরুত্ব: সংশোধিত সংস্করণের মধ্যে পার্থক্য
বিষয়বস্তু বিয়োগ হয়েছে বিষয়বস্তু যোগ হয়েছে
১টি উৎস উদ্ধার করা হল ও ০টি অকার্যকর হিসেবে চিহ্নিত করা হল। #IABot (v2.0beta15) |
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৭৯ নং লাইন:
;Ultrasonic transducer : Ultrasonic waves are passed from a source, through the fluid of interest, and into a detector which measures the acoustic spectroscopy of the waves. Fluid properties such as density and viscosity can be inferred from the spectrum.
;Radiation-based gauge : Radiation is passed from a source, through the fluid of interest, and into a scintillation detector, or counter. As the fluid density increases, the detected radiation "counts" will decrease. The source is typically the radioactive isotope [[cesium-137]], with a half-life of about 30 years. A key advantage for this technology is that the instrument is not required to be in contact with the fluid – typically the source and detector are mounted on the outside of tanks or piping. .<ref>[http://www.ohmartvega.com/en/nuclear_density_DSG.htm Density – VEGA Americas, Inc] {{ওয়েব আর্কাইভ|ইউআরএল=https://web.archive.org/web/20121106105338/http://www.ohmartvega.com/en/nuclear_density_DSG.htm |তারিখ=৬ নভেম্বর ২০১২ }}. Ohmartvega.com. Retrieved on 2011-11-18.</ref>
;Buoyant force transducer : The buoyancy force produced by a float in a homogeneous liquid is equal to the weight of the liquid that is displaced by the float. Since buoyancy force is linear with respect to the density of the liquid within which the float is submerged, the measure of the buoyancy force yields a measure of the density of the liquid. One commercially available unit claims the instrument is capable of measuring specific gravity with an accuracy of ±0.005 SG units. The submersible probe head contains a mathematically characterized spring-float system. When the head is immersed vertically in the liquid, the float moves vertically and the position of the float controls the position of a permanent magnet whose displacement is sensed by a concentric array of Hall-effect linear displacement sensors. The output signals of the sensors are mixed in a dedicated electronics module that provides an output voltage whose magnitude is a direct linear measure of the quantity to be measured.<ref>[http://www.gardco.com/pages/density/electric_hydrometer.cfm Process Control Digital Electronic Hydrometer]. Gardco. Retrieved on 2011-11-18.</ref>
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