Nearly 70 years old, hydraulic fracturing is a core technique for stimulating hydrocarbon production in a majority of oil and gas reservoirs. Complex fluids are implemented in nearly every step of the fracturing process, most significantly to generate and sustain fractures, and transport and distribute proppant particles during and following fluid injection. An extremely wide range of complex fluids are used: naturally occurring polysaccharide and synthetic polymer solutions, aqueous physical and chemical gels, organic gels, micellar surfactant solutions, emulsions, and foams. These fluids are loaded over a wide range of concentration with particles of varying size, and aspect ratio, and are subjected to a extreme mechanical and environmental conditions. We describe the settings of hydraulic fracturing (framed by geology), fracturing mechanics and physics, and the critical role that non-Newtonian fluid dynamics and complex fluids plays in the hydraulic fracturing process.

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The isolation and capture of rare cells is a problem uniquely suited to microfluidic devices, in which geometries on the cellular length scale can be engineered and a wide range of chemical functionalizations can be implemented. The performance of such devices is primarily affected by the chemical interaction between the cell and the capture surface and the mechanics of cell– surface collision and adhesion. As rare cell capture technology has been summarized elsewhere [1], this article focuses on the fundamental adhesion and transport mechanisms in rare cell capture microdevices, and explores modern device design strategies in a transport context. The biorheology and engineering parameters of cell adhesion are defined; adhesion models and reaction kinetics briefly reviewed. Transport at the microscale, including diffusion and steric interactions that result in cell motion across streamlines, is discussed. The review concludes by discussing design strategies with a focus on leveraging the underlying transport phenomena to maximize device performance.

It is well known that the perceived texture and consistency of liquid foods are strong drivers of consumer preference, yet quantification of these parameters is made complicated by the absence of a concise mathematical framework. In this paper, we demonstrate that fractional rheological models, including the fractional Maxwell model (FMM) and the fractional Jeffreys model (FJM), are potential candidates to fill this void as a result of their ability to succinctly and accurately predict the linear and nonlinear viscoelastic response of a range of liquid food solutions. These include a benchmark

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