Concentrated Polymer Brush as Reciprocating Seal Material for Low Leakage and Low Friction

Note: A low leakage liquid seal for micromachined gas valves.

We report a method for addressing gas leakage in micromachined valves. The valves used for evaluating the proposed concept utilize a silicon valve seat that is bonded to a glass substrate and actuated by a piezoelectric stack, all of which are assembled within a ceramic package. The sealing method uses the capillary forces of a liquid sealant on the valve seat to reduce gas leakage below measur...

Bioinspired bottle-brush polymer exhibits low friction and Amontons-like behavior.

We report the design of a bottle-brush polymer whose architecture closely mimics the lubricating protein lubricin. Interaction forces, assessed using a Surface Forces Apparatus (SFA), between two mica surfaces fully covered by the polymer demonstrate that the polymer adopts a loop conformation giving rise to a weak and long-range repulsive interaction force between the surfaces. Under high comp...

Mouse Oocytes and Embryos Cryotop-vitrification Using Low Concentrated Solutions: Effects on Meiotic Spindle, Genetic Material Array and Developmental Ability

Effect of a ring type barrier and rotational speed on leakage flow of gas turbine brush seal

This paper investigates the effect of inserting a ring type barrier on leakage flow of brush seals with different bristles clearances (the distance between bristle pack tip and rotor surface). The ring is placed on both upstream and downstream sides of the bristles. An axisymmetric CFD model is employed to calculate radial pressure distribution along backing plate, axial pressure variation on r...

Low-leakage with Attenuated Material Loss Hybrid Coaxial Cable

We investigate a new mean of decreasing leakage and material loss from coaxial cables using different metallic shield and central conducting part geometries. The suggested model is composed of a central conductor surrounded by 40 metallic wires circularly disposed. The proposed cable is also a hybrid one allowing simultaneous transmission of optical as well as radio frequency (RF) signals. The ...