Abstract:
Polymeric sheets having interconnected microporous networks are generated by contacting the sheets with a composition including solvent and non-solvent in an appropriate ratio and removing the composition from the sheet. Such sheets may be advantageously used in microfluidic devices for a variety of purposes.
Abstract:
The present invention provides a ceramic precursor batch composition comprising inorganic ceramic-forming ingredients, a binder, an aqueous solvent and a chaotropic agent. The presence of the chaotropic agent provides a composition with a lower viscosity and/or a greater batch stiffening temperature allowing for increased extrusion feedrates. Methods for producing a ceramic honeycomb body using the ceramic precursor batch composition of the present invention are also provided.
Abstract:
An optical signal limiter (1) is provided for limiting transmission of a continuous wave optical signal that exceeds a preselected threshold power level. The limiter (1) includes a body (3) having input and output ends (5a, 5b) that is formed at least in part from a material having a negative thermal index coefficient of between about -.5 x 10 &cir& -4 DEG C &cir& -1 and -4.0 x 10 &cir& -4 DEG C &cir& -1 and an absorption coefficient of between 1.0 to 5.0 dB/cm at wavelengths between 980-1650 nm. The limiter (1) also includes collimating fibers (11a, 11b) mounted on the input and output ends (5a, 5b) to minimize low power signal losses across the limiter body (3). It may be installed at a junction between two optical fibers (7, 9) and is preferably formed from a curable adhesive having the aforementioned negative thermal index coefficient to obviate the need for separate bonding materials and joining steps during the installation of the limiter (1). The optical limiter (1) is reusable and with a recovery time of 1-5 milliseconds advantageously prevents power surges in optical circuits from damaging sensitive optical components by limiting the amplitude of such surges within 0.2-0.5 milliseconds.
Abstract:
A method for fabricating an optical device that uses a robust purified adhesive as a bonding agent is disclosed. Impurity particles greater than or equal to 0.1 microns are removed from liquid precursor materials prior to polymerization or cross-linking. The impurity particles are separated from the precursor by applying a high gravitational centrifugal force. The purified adhesive is used to bond together optical components disposed in the optical path of the device. The purified adhesive resists damage from high-powered lasers because impurity particles that would otherwise absorb and scatter laser light are removed from the adhesive.