Collagen gels are widely used in experiments on cell mechanics because they mimic the extracellular matrix in physiological conditions. Collagen gels are often characterized by their bulk rheology; however, variations in the collagen fiber microstructure and cell adhesion forces cause the mechanical properties to be inhomogeneous at the cellular scale....
Liquefaction of saturated granular material due to cyclic loading can result in catastrophic damage to the built environment. The mechanics of liquefaction have been previously studied through field testing, physical modeling, laboratory experiments, and numerical simulations. However, significant questions remain with respect to the particle-scale behavior of granular materials during...
Micro-fluid mixing is an important aspect of many of the various micro-fluidic systems used in biochemical production, biomedical industries, micro-energy systems and some electronic devices. Typically, because of size constraints and laminar flow conditions, different fluids may only have the opportunity to mix by diffusion, which is extremely rate limited....
The effect of unsteady thermocapillary convection on the mass transfer rate of a solute between two immiscible liquids within a rectangular microscale channel with differentially heated sidewalls was numerically investigated. A computational fluid dynamic code in Fortran77 was developed using the finite volume method with Marker and Cell (MAC) technique...
Microscale fluid processes are an increasingly important subgroup of fluid mechanics. Applications for heat transfer and micro-electro-mechanical devices use flows on the scale of less than one hundred microns. This study is part of a larger work in which a multiphase, high shear environment is studied in a microchannel that...
A two-dimensional model was developed to predict concentration profiles from passive, laminar mixing of concentration layers formed in a fractal-like merging channel network. Both flat and parabolic velocity profiles were used in the model. A physical experiment was used to confirm the results of the model. Concentration profiles were acquired...
Several 316 stainless steel meso-scopic devices were made using a diffusion
soldering process. Tensile strength and pressure drop of the devices were
measured and metallurgical examinations were made of the joints. Continuous
bonds were observed in the sample cross-section specimens. Strengths of the
diffusion soldered joints were up to 56%...
A novel design, material, and fabrication method are presented to fabricate a passive micro-ball valve. Microvalves are critical components in microflow control devices used to control the fluid flows in microchannels. These microflow control devices can be integrated with microsensors to form micro analysis systems. Glass/silicon-based fabrication is complicated and...
Stress analysis was performed to determine the maximum stress acting on a railcar coal support-bed, using COSMOS finite element and WFM micromechanics models. The fracture strength of polyurethane impregnated Kevlar 29 fabric, proposed for integration with the railcar structure, was determined experimentally by loading the impregnated coupons in a microcomputer...
The structure and mechanics of tissues affect many important cellular functions such as migration, differentiation, and growth. Mechanical interactions between cells and the extracellular matrix (ECM), as well as ECM-mediated mechanical communication between cells, plays a part in coordinating collective cellular dy- namics during critical processes such as morphogenesis, tissue...