Abstract:
Techniques and compositions are described for reflective coatings and pigments for reflecting electromagnetic radiation, such as visible and solar near-infrared light. In one aspect, a reflective coating includes a base layer having a reflective surface, and an absorber layer formed on the reflective surface of the base layer, in which the reflective coating provides an average reflectance of electromagnetic radiation for wavelengths in the range of 900 nm to 2500 nm irradiated upon the reflective coating greater than substantially 70%, and provides an average reflectance of electromagnetic radiation for wavelengths in the range of 400 nm to 700 nm irradiated upon the reflective coating of less than 40%.
Abstract:
Some embodiments provide apparatuses configured to deploy a landing gear of an aircraft, comprising: a landing gear coupler configured to couple with the landing gear; a release link configured to cooperate the landing gear coupler with a drive shaft that is configured to drive the landing gear between a stowed position and a deployed position; an override driver cooperated with the landing gear coupler; wherein the release link is configured to releasably maintain a relative position of landing gear coupler relative to the drive shaft, and the release link is configured to disengage a coupling between the drive shaft and the landing gear coupler such that the landing gear coupler is configured to move independent of the drive shaft; and wherein the override driver is configured to drive the landing gear coupler to the deployed position.
Abstract:
Embodiments of the present invention provide high durability joints between ceramic articles, particularly between beta-silicon carbide (β-SiC) articles, and methods of making and using the same. In one embodiment, a joint between first and second articles each comprising a ceramic polymorph comprises a matrix comprising the ceramic polymorph and extending between the first and second articles; a plurality of inclusions comprising the ceramic polymorph and being distributed throughout the matrix; and a sealing layer comprising the ceramic polymorph and being respectively disposed on the first and second articles and the matrix.
Abstract:
The present invention provides novel methods for determining the presence or amount of a hydrolytic enzyme in a sample, based on novel substrates for the enzymes, and also provides compositions and methods that provide highly sensitive assay methods for such hydrolytic enzymes.
Abstract:
A method for preparing plutonium-238 (Pu-238) using reactor may include irradiating a liquid containing a neptunium-237 (Np-237) based compounds with neutrons to convert a portion of the Np-237 based compound to a Np-238 based compound; retaining the liquid containing the resulting mixture for a sufficient amount of time for the Np-238 based compound to at least partially convert to a plutonium-238 (Pu-238) based compound. The method further may include separating the Pu-238 based compound from the neptunium based compounds using distillation or chemical method.
Abstract:
A homopolar machine produces an axial counter force on the rotating shaft to compensate for the load on the shaft's thrust bearing to reduce wear and noise and prolong bearing life. The counter force is produced through magnetic interaction between the shaft and the machine's field coils and is created by changing the current excitation of the field coils, which results in a magnetic flux asymmetry in an inner flux return coupled to the shaft. The homopolar machine may also have a configuration that uses current collectors that maintain substantially constant contact pressure in the presence of high magnetic fields to improve current collector performance. The current collectors are flexible and may be made from either electrically conductive fibers or stacked strips such that they bear up against the armature so that the pressure is maintained by the spring constant of the current collector material. The homopolar machine may also have a configuration where the brushes are oriented so that the current is aligned as much as is practical with the local magnetic field lines so as to reduce the lateral electromagnetic forces on the brushes.
Abstract:
An electromagnetic gun and rotating pulsed network system that includes a gun barrel coupled to a gun mount coupled on a rotating deck of a navel ship. A pulse forming network provides pulsed energy to the electromagnetic gun, and the pulse forming network is cylindrical in shape so as to be rotatable within a cylindrical bulkhead within the ship. The pulse forming network may rotate in unison with the gun barrel allowing cables to couple the pulse forming network and the cable barrel. The pulse forming network includes wedge shaped capacitors that, when positioned sided by side, collectively form a substantially circular shape.
Abstract:
A method and apparatus for operation in a multi-frequency band wideband system in the presence of an interference, the method comprising the steps: receiving signaling in a plurality of wideband frequency sub-bands, each wideband frequency sub-band having a different center frequency, wherein a bandwidth of each wideband frequency sub-band is at least 2 percent of a center frequency of the wideband frequency sub-band; detecting an interfering signal having signal energy in a portion of a respective sub-band of the wideband frequency sub-bands; modifying at least one of a center frequency and a bandwidth of the respective sub-band in order to operate in the presence of the interfering signal; and instructing a transmitting device transmitting the signaling to transmit subsequent signaling accounting for the modification of the center frequency of the respective sub-band.
Abstract:
An apparatus for producing a stable, high pressure plasma column with long length, and high axial uniformity. Rotating a gas-filled tube about an horizontal axis creates a vortex with minimal, or no shear flow. Such a vortex provides a stable equilibrium for a central column of high temperature gas and plasma when, for a given rotation speed, the centrifugal force dominates over the gravitational force inside the smallest radial dimension of the containment envelope. For gas pressures sufficiently high that the particle mean free path is short compared with the thickness of the gas layer between the central plasma column and the wall, thermal transport across this sheath layer is small and its temperature is low. High pressure discharges inside a rotating envelope may be sustained by a variety of means, including electrical, electromagnetic and chemical; they may find application in plasma torches, light sources, etc. One preferred embodiment used direct current between co-rotating electrodes to sustain a one-meter-long plasma column less than 5 mm in diameter. Another preferred embodiment employed microwave heating to produce a perfectly centered plasma flame 0.5 meters long into which tens of kilowatts of power can be coupled.
Abstract:
A battery system may include multiple battery cells grouped into modules. Each battery module may have a diffuser plate to direct the hot gases and molten material that are ejected during cell failure. The gas and material may be directed away from the nearest neighboring cells in the event of a single cell thermal runaway. Residual thermal energy is wicked away, absorbed or contained to keep heat away from the neighboring cells. These and other features may manage the blast energy and residual thermal energy of a single cell failure event. This may prevent a cascading failure of the larger battery system, thereby mitigating the risk of injury to personnel and property.