United States of America As Represented by the Administrator of Nasa

Other

Dennis Stephen Tucker

Michael D Harold

Terry D Rolin

Curtis W Hill

Jeremy A Tucker

Pedro A Capó-Lugo

Michael R LaPointe

Shin-Ping Liu

Nano-sized particles of barium-titanate are heated as a gas mixture of 25% hydrogen and 75% nitrogen is passed there through yielding particles of barium-titanate having oxygen vacancies therein. The particles of barium-titanate having oxygen vacancies therein are coated with silica yielding silica-coated particles having a silica coating thickness in a range of 2-5 nanometers. The silica-coated particles are sintered by application of pressure in a range of 35-50 megapascals and temperature in a range of 950-1050&#xb0; C. The sintered quantity of material is cooled at a cooling rate in a range of 1-3&#xb0; C. per minute at least until the temperature thereof is less than 120&#xb0; C.

Method of fabricating high-permittivity dielectric material

In a unit gravity environment, a glass preform is encased in a material to generate an encased glass preform. The material remains solid at the glass preform's crystal melting temperature and is inert with respect to the glass preform. The encased glass preform is placed in a microgravity environment and heated to a temperature above the crystal melting temperature until the glass preform melts and is free of crystals, wherein a crystallite-free glass preform is encased within the material. The crystallite-free glass preform is then cooled in the microgravity environment to generate a solid crystallite-free glass preform encased within the material. While still in the microgravity environment, the material encasing the solid crystallite-free glass preform is removed in the microgravity environment and the solid crystallite-free glass preform is polished. A glass optical fiber is then drawn from the solid crystallite-free glass preform in the microgravity environment.

Microgravity-based method and system for fabricating optical fibers

A vibrating gyroscope includes a piezoelectric strip having length and width dimensions. The piezoelectric strip includes a piezoelectric material and carbon nanotubes (CNTs) substantially aligned and polled along the strip's length dimension. A spindle having an axis of rotation is coupled to the piezoelectric strip. The axis of rotation is parallel to the strip's width dimension. A first capacitance sensor is mechanically coupled to the spindle for rotation therewith. The first capacitance sensor is positioned at one of the strip's opposing ends and is spaced apart from one of the strip's opposing faces. A second capacitance sensor is mechanically coupled to the spindle for rotation therewith. The second capacitance sensor is positioned at another of the strip's opposing ends and is spaced apart from another of the strip's opposing faces. A voltage source applies an AC voltage to the piezoelectric strip.

Carbon nanotube tape vibrating gyroscope

A single-axis accelerometer includes a housing defining a sleeve. An object/mass is disposed in the sleeve for sliding movement therein in a direction aligned with the sleeve's longitudinal axis. A first piezoelectric strip, attached to a first side of the object and to the housing, is longitudinally aligned with the sleeve's longitudinal axis. The first piezoelectric strip includes a first strip of a piezoelectric material with carbon nanotubes substantially aligned along a length thereof. A second piezoelectric strip, attached to a second side of the object and to the housing, is longitudinally aligned with the sleeve's longitudinal axis. The second piezoelectric strip includes a second strip of the piezoelectric material with carbon nanotubes substantially aligned along a length thereof. A voltage sensor is electrically coupled to at least one of the first and second piezoelectric strips.

Single-axis accelerometer

A method is provided for eliminating crystals in non-oxide optical fiber preforms as well as optical fibers drawn therefrom. The optical-fiber-drawing axis of the preform is aligned with the force of gravity. A magnetic field is applied to the preform as it is heated to at least a melting temperature thereof. The magnetic field is applied in a direction that is parallel to the preform's optical-fiber-drawing axis. The preform is then cooled to a temperature that is less than a glass transition temperature of the preform while the preform is maintained in the magnetic field. When the processed preform is to have an optical fiber drawn therefrom, the preform's optical-fiber-drawing axis is again aligned with the force of gravity and a magnetic field is again applied along the axis as the optical fiber is drawn from the preform.

Eliminating crystals in non-oxide optical fiber preforms and optical fibers

A process for producing foamed aluminum in space comprising the steps of: heating aluminum until it is molten; applying the force of gravity to the molten aluminum; injecting gas into the molten aluminum to produce molten foamed aluminum; and allowing the molten foamed aluminum to cool to below melting temperature. The apparatus for carrying out this invention comprises: a furnace which rotates to simulate the force of gravity and heats the aluminum until it is molten; a door on the furnace, which is opened for charging the aluminum into the furnace, closed for processing and opened again for removal of the foamed aluminum; a gas injection apparatus for injecting gas into the molten aluminum within the furnace; and an extraction apparatus adjacent the door for removing the foamed aluminum from the furnace.

Orbital fabrication of aluminum foam and apparatus therefore

This invention is a process for producing foamed material in space comprising the steps of: rotating the material to simulate the force of gravity; heating the rotating material until it is molten; extruding the rotating, molten material; injecting gas into the extruded, rotating, molten material to produce molten foamed material; allowing the molten foamed material to cool to below melting temperature to produce the foamed material. The surface of the extruded foam may be heated to above melting temperature and allowed to cool to below melting temperature. The extruded foam may also be cut to predetermined length. The starting material may be metal or glass. Heating may be accomplished by electrical heating elements or by solar heating.

Orbital foamed material extruder

A system, method and algorithm for performing statistical analysis on an input data source to determine an optimal token size resulting in an increased ratio value is described. Changes to the values of the tokens prior to compression may result in an overall compression increase even if the data source has been previously compressed. Specific techniques for modifying the tokens include varying the base size, rearrangement of the tokens, and modifications by matrix multiplication. After modification of the tokens, compression of the data using one or more lossless compression methods may be performed. The technique may be repeated by using the output of previous compression processes as input to additional entropy and compression optimization.

Growing community of inventors

Huntsville, AL, United States of America

Dennis Stephen Tucker