Conventional endotracheal tubes have high intrinsic resistive properties due to their high outer-to-inner diameter ratio. This has significant disadvantages in the treatment of the small neonatal or pediatric patient as work of breathing increases with decreasing internal radius. Diagnostic and therapeutic procedures, including suctioning, may be very difficult in patients with small endotrache...

this paper investigates axial compression process of multi-layered tubes with circular cross-section under the axial loading in the quasi-static condition using experimental method. some specimens are prepared in seven different groups, namely; empty carbon/epoxy composite tubes, solid carbon/epoxy composite rods, empty copper tubes, composite tubes with silicon sealant filler, concentrically s...

We investigated the fabrication of highly porous scaffolds made of three different materials [poly(propylene fumarate) (PPF) polymer, an ultra-short single-walled carbon nanotube (US-tube) nanocomposite, and a dodecylated US-tube (F-US-tube) nanocomposite] in order to evaluate the effects of material composition and porosity on scaffold pore structure, mechanical properties, and marrow stromal ...

This study investigates the effects of nanostructure size and surface area on the rheological properties of un-cross-linked poly(propylene fumarate) (PPF) nanocomposites and the mechanical properties of cross-linked nanocomposites as a function of the nanostructure loading. Three model carbon nanostructures were examined, C(60) fullerenes, ultra-short single-walled carbon nanotubes (US-tubes) a...

Laminar and Turbulent Flow. If a fluid flows through a long, smooth-walled, narrow tube at a low flow rate, flow is likely to be “laminar.” Here the particles of fluid travel parallel to the sides of the tube. This is often the case for blood flowing in veins. Flow is proportional to the pressure difference (Figure 2A). The viscosity of the fluid is an important determinant of the relationship ...

Using predesigned trains of femtosecond optical pulses, we have selectively excited coherent phonons of the radial breathing mode of specific-chirality single-walled carbon nanotubes within an ensemble sample. By analyzing the initial phase of the phonon oscillations, we prove that the tube diameter initially increases in response to ultrafast photoexcitation. Furthermore, from excitation profi...

Metallic single-walled carbon nanotubes have been proposed to be good one-dimensional conductors. However, the finite curvature of the graphene sheet that forms the nanotubes and the broken symmetry due to the local environment may modify their electronic properties. We used low-temperature atomically resolved scanning tunneling microscopy to investigate zigzag and armchair nanotubes, both thou...