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A modulated metamaterial that exhibits both time-periodic stiffness and mass simultaneously is presented. The metamaterial element includes a primary body that undergoes infinitesimal motion, and is connected to a dynamic-mechanism structure, involving a rotational body, and spring with a large-scale motion, which is designed to produce a time-modulated linear momentum and elastic constraint for the primary body. The non-reciprocal wave propagation is then investigated in a space-time lattice metamaterial that is constructed by coupling doubly time-modulated elements with linear springs of constant stiffness. The dispersion property shows the frequency degeneracy occurring at the center or edge of the Brillouin zone, and the unidirectional bandgap at certain frequencies. This phenomenon represents a unique property of the doubly modulated metamaterials compared to the singly modulated ones, thus may provide more promising applications to the design of non-reciprocal devices. [ABSTRACT FROM AUTHOR]

Thermosolutocapillary convection within a rectangular cavity with dynamic free surface is numerically investigated in the absence of gravitational effects. Both the temperature and solute concentration gradients are applied horizontally. The free surface deformation is captured by the level set method. Two cases of the ratio of thermal to solutal Marangoni number Rσ < -1 and Rσ = -1 are considered. For Rσ < -1, the free surface bulges out near the left wall and bulges in near the right wall; with the increase of Marangoni number, the free surface deformation decreases and with the increase of capillary number and aspect ratio, it increases. For Rσ = -1, the free surface bulges out near the left and right walls and bulges in at the central zone; with the increase of Marangoni number, the free surface deformation mode is changed and with the increase of capillary number and aspect ratio, the free surface deformation increases. [ABSTRACT FROM AUTHOR]

Hollow fiber modules are commonly used to conveniently and efficiently remove cryoprotective agents (CPAs) from cryopreserved cell suspensions. In this paper, a steady-state model coupling mass transfers across cell and hollow fiber membranes is theoretically developed to evaluate the removal of CPAs from cryopreserved blood using hollow fiber modules. This steady-state model complements the unsteady-state model, which was presented in our previous study. The steady-state model, unlike the unsteady-state model, can be used to evaluate the effect of ultrafiltration flow rates on the clearance of CPAs. The steady-state model is validated by experimental results, and then is compared with the unsteady-state model. Using the steady-state model, the effects of ultrafiltration flow rates, NaCI concentrations in dialysate, blood flow rates and dialysate flow rates on CPA concentration variation and cell volume response are investigated in detail. According to the simulative results, the osmotic damage of red blood cells can easily be reduced by increasing ultrafiltration flow rates, increasing NaCl concentrations in dialysate, increasing blood flow rates, or decreasing dialysate flow rates. [ABSTRACT FROM AUTHOR]