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Aurore F. Quelennec, Jason J. Gorman, Darwin Reyes-Hernandez
We present a label-free SAW-based flow sensor with enhanced precision and repeatability. This sensor improves the signal-to-noise ratio by one order of magnitude (dB scale) at an optimized frequency, and lowers the measurable flow rate to 5 μL/min (from
Nikita Podobedov, Matthew DiSalvo, Jason A. Hsu, Paul Patrone, Gregory A. Cooksey
Flow cytometers are indispensable for clinical studies, yet are hindered by inherent uncertainties. We have developed an optofluidic device capable of multiple measurements along a microfluidic channel, whereby many of the uncertainty components can be
Microfluidics are increasingly used to develop flow cytometers with novel functionalities. Although various approaches exist to control particle positioning within microfluidics, the magnitude and mechanisms of measurement uncertainties that arise from
Gregory A. Cooksey, Paul Patrone, James R. Hands, Stephen E. Meek, Anthony J. Kearsley
This work describes a new method for continuous measurement of flow in a microchannel from 1 nL/min to 1000 nL/min using an optofluidic device with waveguides that deliver and collect light from small regions of a microfluidic channel. By relating the
Coriolis mass flowmeters are known to be stable, have low uncertainty (± 0.1 %), and are insensitive to fluid properties. This meter type is used for many applications, including as transfer standards for proficiency testing and liquified natural gas (LNG)
Boyang Qin, Ranjiangshang Ran, Paul Salipante, Steven Hudson, Paulo E. Arratia
Using holographic particle tracking, we report the three-dimensional flow structure organizing the viscoelastic instability in cross-channel flow. Beyond a critical Wi, the advective core flow undergoes an out-of-plane instability marked by the emergence
Paul Salipante, Vishnu Dharmaraj, Steven D. Hudson
The viscosity of a shear-banding wormlike micelle solution at high shear rates is investigated using capillary rheology and particle streak velocimetry. Measurements of the flow profile and pressure gradient show an extended entrance region, which exceeds
Nicos Martys, William L. George, Ryan P Murphy, Kathleen M Weigandt
Measurement and prediction of suspension flow properties in cylindrical geometries represents a significant challenge for both the experimentalist and modeller. In this paper, results of a computational study of suspension flow in a pipe geometry using a
Aaron N. Johnson, Iosif I. Shinder, Bernard J. Filla, Joey T. Boyd, Rodney A. Bryant, Michael R. Moldover, Thomaa D. Martz, Matthew Gentry
Exhaust flows from coal-fired electricity-generating-plants are determined by measuring the flue gas velocity at prescribed points in the stack cross section. These velocity measurements are made using EPA-approved differential pressure probes such as the
The orthogonal superposition (OSP) technique is advantageous for measuring structural dynamics in complex fluids subjected to a primary shear flow. This technique superimposes a small amplitude oscillation orthogonal to a primary shear flow to measure the
Boyang Qin, Paul Salipante, Steven Hudson, Paulo E. Arratia
The flow of viscoelastic fluids in channels and pipes remain poorly understood, particularly at low Reynolds numbers. Here, we investigate the flow of polymeric solutions in straight channels using pressure measurements and particle tracking. The law of
A longstanding goal in polymer rheology is to develop a physical picture that relates the growth of mechanical moduli during polymer crystallization to that of structure. Here we utilize simultaneous mechanical rheology and optical microscopy, with
Aurore F. Quelennec, Jason J. Gorman, Darwin Reyes-Hernandez
This paper presents a calibration/label-free flow sensor embedded in a microfluidic system. This sensor is based on surface acoustic waves, where the acoustic intensity is dependent on the flow rate of the propagating medium. The range of flow rates
Gregory A. Cooksey, Paul N. Patrone, James R. Hands, Stephen E. Meek, Anthony J. Kearsley
The ultimate performance of flow-based measurements in microfluidic systems is limited by their accuracy at the nanoliter-per-minute scale. But improving such measurements (especially in contexts that require continuous monitoring) is challenging because
Jodie Gail Pope, Keith A. Gillis, Michael R. Moldover, Eric Harman, James Mehl
We describe our progress in the development of a novel gas flow standard using the acoustic and microwave resonances of a 1.85 m3, nearly-spherical, steel vessel at pressures up to 7 MPa. For flow calibrations using pressure and acoustic frequency
Aaron N. Johnson, Iosif I. Shinder, Bernard J. Filla, Joey T. Boyd, Rodney A. Bryant, Michael R. Moldover
Exhaust flows from coal-fired stacks are determined by measuring the flue gas velocity at prescribed points in the stack cross section. During the last 30+ years these velocity measurements have been made predominantly using S-type pitot probes. These
The custody transfer of petroleum worth $1 × 10 12 / year is traced to the volume delivered from provers and liquid test measures. Mistakes as small as 0.02 % in a custody meter calibration can lead to multi-million dollar corrections in bills. NIST
New applications in biology, medicine, and manufacturing require reliable measurements of liquid flows smaller than 100 υL/min. NIST addressed this requirement by improving the reliability and ease of use of NISTs Dynamic Gravimetric Micro-Flow Standard
This publication contains Good Measurement Procedures (GMP), Good Laboratory Procedures (GLP), and Standard Operating Procedures (SOP) for use in calibration laboratories performing volumetric calibrations. It includes procedures for Volume Transfer and
Ran Tao, Kirk D. Rice, Aaron M. Forster, Randy A. Mrozek, Shawn T. Cole, Reygan M. Freeney, Anicet Djakeu Samen
Roma Plastilina No. 1 (RP1), a ballistic clay, is essential for establishing injury limits in standards-based ballistic resistance testing of body armor. It serves as a ballistic witness material (BWM), behind the armor, where the magnitude of plastic
Arno D. Laesecke, Clemens Junker, Damian S. Lauria
The viscosities of three pentaerythritol tetraalkanoate ester base oils and one fully formulated lubricant were measured with an oscillating piston viscometer in the combined temperature range from 275 K to 450 K with pressures to 137 MPa. The alkanoates
Boyang Qin, Paul Salipante, Steven Hudson, Paulo E. Arratia
The viscoelastic flow past cylinder is a classic benchmark problem that is not completely understood. Using novel holographic particle velocimetry, we report two main discoveries of the elastic instability upstream of a single cylinder in confined channel
Yoav Kessler, Robert Ilic, Slava Krylov, Alexander Liberzon
We report on a flow velocity measurement technique based on snap-through detection of an electrostatically actuated, bistable micromechanical beam. We show that induced elecro-thermal Joule heating and the convective air cooling change the beam curvature