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Paul Salipante, Michael Cromer, Gerardo Pradillo Macias, Steven Hudson
Viscoelastic flow instabilities limit polymer processing rates. High-speed optical measurements of stress and flow are used to provide insight into the relationships between polymer orientation and flow field that lead to viscoelastic fluctuations and
Elizabeth Benham, Kristen Dill, Dinelka Jagoda, Maryanne Amanze, Yoon Thwel
The metric system (International System of Units, SI) is easy to use and learn. The Metric System Estimation Game is a fun, hands-on activity that helps participants become familiar with SI measurements by practicing estimation skills. During this activity
Paul Salipante, Ryan Murphy, Steve Kuei, Jeffrey Fagan, Christopher Sims, Kathleen Weigandt, Steven Hudson
Rod-like particles are efficient rheology modifiers and are commonly found in a variety of biological and industrially relevant suspensions, from biofilaments to worm-like surfactant micelles. These suspensions display strong shear-thinning behavior, and
Christopher Crowley, Iosif Isaakovich Shinder, Michael R. Moldover, Joey Boyd, James Filla, Aaron Johnson
Laser Doppler anemometers (LDAs) use scattered light to determine velocity components of a flowing fluid. The operating principal of LDAs is simple conceptually; however, it is impractical to trace the LDA-determined velocities to the SI by characterizing
Applications often expose wormlike micelle solutions to a very wide range of shear and temperature conditions. The two-species model presented in Part I [Salipante et al., J. Rheol. 68 (2024)] describes the nonlinear rheology over a wide range of shear
We investigate the universality of entanglement kinetics in polymer melts. We compare predictions of a recently developed constitutive equation for disentanglement to molecular dynamics simulations of both united-atom polyethylene and Kremer-Grest models
Stian Romberg, Paul Roberts, Chad R. Snyder, Anthony Kotula
Simultaneous rheology and conversion measurements of neat and composite epoxy resins reveal that conventional models neither accurately nor fully describe the relationship between rheology and conversion. We find that models predicting thermoset conversion
Nicholas Drachman, Paul Patrone, Gregory A. Cooksey
Accuracy and temporal resolution of flow meters are often unacceptable below the microliter per minute scale, limiting their ability to evaluate the real-time performance of many microfluidic devices. For conventional flow meters, this problem arises from
The NIST Neutron Source, or NNS, is a proposed reactor designed to eventually replace the aging National Bureau of Standards Reactor at the NIST Center for Neutron Research (NCNR). The NNS is a light water moderated and cooled, compact reactor used to
Iosif Isaakovich Shinder, Aaron Johnson, James Filla, Vladimir B. Khromchenko, Michael R. Moldover, Joey Boyd, John D. Wright, John R. Stoup
We present protocols for making fast, accurate, 3-D velocity measurements in the stacks of coal-fired power plants. The measurements are traceable to internationally-recognized standards; therefore, they provide a rigorous basis for measuring and/or
Thermoset composites are excellent candidates for material extrusion because they shear thin during extrusion but retain their shape once deposited via a yield stress. However, thermal post-curing is often required to solidify these materials, which can
Jodie Gail Pope, Keith A. Gillis, James W. Schmidt
We measured gas flows exiting large, un-thermostated, gas-filled, pressure vessels by tracking the time-dependent pressure P(t) and resonance frequency fN(t) of an acoustic mode N of the gas remaining in each vessel. This is a proof-of-principle
The use of microfluidics to make mechanical property measurements is increasingly common. Fabrication of microfluidic devices has enabled various types of flow control and sensor integration at micrometer length scales to interrogate biological materials
John D. Wright, Aaron Johnson, Michael R. Moldover, Shin-ichi Nakao
We review diverse types of gas flow standards that are used to calibrate other gas flow meters. For each type of standard, we describe the principles of its operation and at least one hardware example. We identify the practical limits of the example's
Jin Yang, Yue Yin, Alexander Landauer, Selda Buyukozturk, Jing Zhang, Luke Summey, Alexander McGhee, Matthew Fu, John Dabiri, Christian Franck
We present a new particle tracking algorithm to accurately resolve large deformation and rotational motion fields, which takes advantage of both local and global particle tracking algorithms. We call this method the ScalE and Rotation Invariant Augmented
Selda Buyukozturk, Alexander Landauer, Jing Zhang, Luke Summey, Angel Chukwu, Christian Franck
Background: High strain-rate deformations of soft materials have several applications which presents an experimental need to measure at-rate 3D volumetric spatial information. While 2D- and 3D-digital image correlation, digital volume correlation, and
Vania Silverio, Suvajyoti Guha, Armelle Keiser, Rucha Natu, Darwin Reyes-Hernandez, Henne van Heeren, Nicolas Verplanck, Luke Herbertson
The miniaturization of laboratory procedures for Lab-on-Chip (LoC) devices and translation to various platforms such as single cell analysis or Organ-on-Chip (OoC) systems are revolutionizing the life sciences and biomedical fields. As a result
We demonstrate a capillary device used to measure the shear rate dependent viscosity of microliter scale volumes. Liquid samples are driven pneumatically to fill a microcapillary and partially fill a larger glass capillary. The glass capillary is mounted
Dianne L. Poster, Matthew Hardwick, C Cameron Miller, Michael A. Riley, W. W. Shanaka I. Rodrigo, Andras E. Vladar, John D. Wright, Christopher D. Zangmeister, Clarence Zarobila, Jeremy Starkweather, John Wynne, Jason Yilzarde
Data for interpreting virus inactivation on N95 face filtering respirators (FFRs) by ultraviolet (UV) radiation are important in developing UV strategies for N95 FFR disinfection and reuse for any situation, whether it be everyday practices, contingency
Jalal Sadeghi, Paul Patrone, Anthony J. Kearsley, Gregory A. Cooksey
Performance improvements in microfluidic systems depend on accurate measurement and control of fluids on the micro- and nanoscale, and new applications are continuously moving the needle to lower volumetric flow rates. This work focuses on improving an
John D. Wright, Aaron Johnson, Michael R. Moldover, Woong Kang, Liang Zhang, Bodo Mickan
We improve the usefulness of small (diameter 10 mm) critical flow venturis (CFVs) as transfer standards for gas flow by measuring and explaining how their discharge coefficients depend on the temperature T of their environment. At Reynolds numbers Re 2.5
Oil and gas production industries use large (diameter > 0.8 m) ultrasonic flow meters (USMs) to measure exhaust gas from flare stacks, emissions from smokestacks, flow of natural gas, etc. Since most flow laboratories do not have compressors with
Darwin R. Reyes-Hernandez, Henne van Heeren, Suvajyoti Guha, Luke Herbertson, Alexios P. Tzannis, Jens Ducr?e, Hugo Bissig, Holger Becker
The microfluidics industry has grown steadily over the last 5 years worldwide, with the market for microfluidic medical devices experiencing a compound growth rate of 18%. The number of submissions to regulatory agencies such as the U.S. Food & Drug
Orthogonal superposition (OSP) rheology is an advanced rheological technique that involves superimposing a small-amplitude oscillatory shear deformation orthogonal to a primary shear flow. This technique allows the measurement of structural dynamics of