PURPOSE Membrane-based Tangential Flow Filtration (TFF) unit operations are used for clarifying, concentrating, and purifying proteins. This technical brief is a practical introduction to protein processing using tangential flow filtration. It is intended to help scientists and engineers achieve their protein processing objectives by discussing how the choice of key components and operating par...

We provide a brief overview of the Discrete Element Method (DEM) for modeling large frictional contact problems in granular flow dynamics and quasi-static geomechanics applications. In terms of contact, DEM can be divided into two approaches: the Constraint Method (CM) or rigid-body approach, and the Penalty Method (PM) or soft-body approach. We give a detailed presentation of a DEM-PM contact ...

Metasurfaces formed by monopole and dipole resonators are studied theoretically. The Helmholtz or membranes vibrating on the first eigenfrequency; ones spheres springs second eigenfrequency. It is shown that acoustic properties of metasurface built-in can be described an equivalent impedance, which characterizes a normal forcing to surface, whereas this impedance not suitable for resonators, be...