Xerox Corporation

Sandia Corporation

National Technology & Engineering Solutions of Sandia, LLC

Other

Kevin R Zavadil

Paul Charles Galambos

George J Roller

Arthur M Gooray

Joseph Michael Crowley

Frank J Peter

Richard C Givler

Leonard M Carreira

Donald B King

Laura Biedermann

Marcel Philippe Breton

Raymond W Wong

David R Wheeler

Jeffry Joseph Sniegowski

Randy J Shul

Gregory A Vawter

Christine E Bedford

Stanley H Kravitz

Michael Hibbs

Chris P Tigges

William M Lindenfelser

Brian P Dwyer

Albert C Marshall

Judith A Ruffner

D Russell Humphreys

Frederick J Glasscott

Charles P Morrow

Christi Willison Gober

Phillip I Pohl

Paul Crozier

Joseph M Crowley, Jr

A membrane assembly is provided. The membrane assembly includes a non-metallic, porous substrate. A graphene oxide membrane is formed over the non-metallic, porous substrate. A chemical linker interface covalently binds the graphene oxide membrane to the non-metallic, porous substrate.

Filtration membranes

A heat exchanger that includes a membrane of graphene oxide is disclosed, as is a heat exchange system employing such a heat exchanger. The heat exchanger permits the use of water from non-traditional sources, such as waste water, brackish and sea water, in a cooling loop. Clean water and sensible heat permeate through the membrane, simultaneously cooling and purifying water in the cooling loop.

System and method for cooling using a heat exchanger having a membrane

The present invention relates to an ink composition including water, a solvent, a solvent-soluble dye, and a surfactant, where the ink exhibits a stable liquid microemulsion phase at a first temperature and a second temperature higher than the first temperature and has a conductivity of at most about 200 &#x3bc;S/cm and a dielectric constant of at least about 60, and methods of making such ink compositions. The present invention also relates to a method of making an ink composition for use in a microelectromechanical system-based fluid ejector. The method involves providing a solution or dispersion including a dye or a pigment and adding to the solution or dispersion an additive which includes a material that enhances dielectric permittivity and/or reduces conductivity under conditions effective to produce an ink composition having a conductivity of at most about 200 &#x3bc;S/cm and a dielectric constant of at least about 60.

Tailored ink for piston driven electrostatic liquid drop modulator

A self-powered microthermionic converter having an internal thermal power source integrated into the microthermionic converter. These converters can have high energy-conversion efficiencies over a range of operating temperatures. Microengineering techniques are used to manufacture the converter. The utilization of an internal thermal power source increases potential for mobility and incorporation into small devices. High energy efficiency is obtained by utilization of micron-scale interelectrode gap spacing. Alpha-particle emitting radioisotopes can be used for the internal thermal power source, such as curium and polonium isotopes.

Self-powered microthermionic converter

Low work function materials are disclosed together with methods for their manufacture and integration with electrodes used in thermionic conversion applications (specifically microminiature thermionic conversion applications). The materials include a mixed oxide system and metal in a compositionally modulated structure comprised of localized discontinuous structures of material that are deposited using techniques suited to IC manufacture, such as rf sputtering or CVD. The structures, which can include layers are then heated to coalescence yielding a thin film that is both durable and capable of electron emission under thermionic conversion conditions used for microminiature thermionic converters. Using the principles of the invention, thin film electrodes (emitters and collectors) required for microconverter technology are manufactured using a single process deposition so as to allow for full fabrication integration consistent with batch processing, and tailoring of emission/collection properties. In the preferred embodiment, the individual layers include mixed BaSrCaO, scandium oxide and tungsten.

Low work function materials for microminiature energy conversion and recovery applications

Structures for use in conjunction with surface micromachined structures are formed using a two-step etching process. In various exemplary embodiments, the two-step etching process comprises a modified Bosch etch. According to various exemplary embodiments of the two-step etch, first mask and second masks are used to prepare a layer for etching one or more desired structures. The first mask is used to define at least one large feature. The second mask is used to define at least one small feature (small as compared to the at least one large feature). The second mask is formed over the first mask which is formed over the layer. In the first etching step, the at least one small feature is etched into the layer. Then, the second mask is removed using the chemical rinsing agent. In the second etching step, the at least one large feature is etched into the layer such that the at least one small feature propagates further into the layer ahead of the at least one large feature. The first mask is then removed. Other surface micromachined methods and structures are provided as well.

Surface micromachined structure fabrication methods for a fluid ejection device

An electronic drive system applies a drive signal to an electrostatically actuated device such that a resulting electric field has a constant force. In various exemplary embodiments, the electronic drive system applies a drive signal to an electrostatically actuated fluid ejector that has a piston and a faceplate including a nozzle hole. A dielectric fluid to be ejected is supplied between the piston and the faceplate. The drive signal is applied to one of the piston and the faceplate. The drive signal generates an electric field across the fluid between the piston and the faceplate. The electric field causes the piston to be electrostatically attracted towards the faceplate so that a jet or drop of fluid is ejected through the nozzle hole of the faceplate. According to exemplary embodiments, the drive signal is from a constant current source or is reduced over the course of its lifetime. Further, according to various exemplary embodiments, the drive signal is of a suitable high frequency to reduce the potential of electrochemical reactions or electrical breakdown, or both. The drive signal may also be a bi-polar drive signal to reduce the possibility of electrochemical reactions.

Electronic drive systems and methods

A piston structure is movably mounted within a fluid chamber. Movement of the piston structure towards a faceplate causes a portion of the fluid between the piston and the faceplate to be forced out of the nozzle hole in the faceplate, forming a drop or jet of the fluid. Viscous forces that are generated by the flow of fluid along a working surface of the piston structure toward and away from the nozzle hole generate a force that resists the movement of the piston structure. This resistance force tends to slow the piston motion, and prevents the piston from contacting the faceplate. In various embodiments, the fluid chamber is defined by a cylinder structure. The piston structure moves within the cylinder structure. The cylinder structure and the faceplate define the fluid chamber. The cylinder structure and the piston structure are designed to cooperate so that the movement of the piston structure within the cylinder structure ejects fluid according to various design criteria. In various embodiments, a free space is provided between the faceplate and the piston structure at its maximum displacement towards the faceplate.

Micromachined fluid ejector systems and methods having improved response characteristics

A bi-directional fluid ejector according to the systems and methods of this invention operates on the principle of electrostatic attraction. In various exemplary embodiments, the fluid ejector includes a sealed dual diaphragm arrangement, an electrode arrangement that is parallel and opposite to the sealed diaphragms, and a structure which contains the fluid to be ejected. A diaphragm chamber containing a relatively incompressible fluid is situated behind, and is sealed by, the diaphragms. At least one nozzle hole is formed in a faceplate of the ejector over one of the diaphragms. A drive signal is applied to at least one electrode of the electrode arrangement to generate an electrostatic field between the electrode and a first one of the diaphragms. The first diaphragm is attracted towards the electrode by an electrostatic force into a deformed shape due to the electrostatic field. Upon deforming, pressure is transmitted to a second one of the sealed diaphragms. The transmitted pressure and the relatively incompressible nature of the fluid contained within the sealed diaphragm chamber causes the second diaphragm to deflect in the opposite direction to force fluid through at least one of the at least one nozzle hole. After a drop is ejected, the movement is reversed, either through normal resilient restoration actions of the deformed diaphragm and/or through an applied force.

Bi-directional fluid ejection systems and methods

A fluid ejection system according to this invention operates on the principle of electrostatic or magnetic attraction. In various exemplary embodiments, the fluid ejection system includes a sealed diaphragm arrangement having at least one diaphragm portion and a diaphragm chamber defined at least partially by the at least one diaphragm portion, a nozzle hole located over the at least one diaphragm portion, an ejection chamber defined between the nozzle hole and the least one diaphragm portion and a secondary dielectric fluid reservoir containing a secondary dielectric fluid. The ejection chamber receives a primary fluid to be ejected. The secondary dielectric fluid reservoir is in fluid communication with the diaphragm chamber to supply the secondary dielectric fluid to the diaphragm chamber. In various exemplary embodiments, the secondary dielectric fluid is a liquid, a substantially incompressible fluid, and/or a high performance dielectric fluid having a dielectric constant greater than 1.

Fluid ejection systems and methods with secondary dielectric fluid

An electrostatic microelectromechanical system (MEMS) based fluid ejector comprises a movable piston structure and a stationary faceplate. A fluid chamber is defined between the piston structure and a substrate. The piston structure may be resiliently mounted on the substrate by one or more spring elements. A fluid to be ejected is supplied in the fluid chamber from a fluid reservoir through a fluid refill hole formed in the substrate. The faceplate includes a nozzle hole through which a fluid jet or drop is ejected. In various exemplary embodiments, the piston structure moves towards the faceplate by electrostatic attraction between the piston structure and the faceplate. As a result of the movement of the piston structure, a portion of the fluid between the piston structure and the faceplate is forced out of the nozzle hole, forming a jet or drop of the fluid.

Micromachined fluid ejector systems and methods

The systems and methods of the present invention operate by magnetically driving a fluid ejector. In various exemplary embodiments, a primary coil and a secondary coil are situated in the ejector. The ejector has a movable piston usable to eject fluid through a nozzle hole. The piston may be resiliently mounted and biased to an at-rest position. A drive signal is applied to cause current to flow in the primary coil. The current flow generates a magnetic field that induces a current in the secondary coil. Either the primary coil or the secondary coil or associated with the piston and the other is associated with a fixed structure of the ejector. As a result, a magnetic force is generated that pushes the piston either toward a faceplate so that a drop of fluid is ejected through the nozzle hole in the faceplate or away from the faceplate so that fluid fills in a fluid chamber between the piston and the faceplate. When the drive signal is turned off, the piston resiliently returns to its at-rest position, thereby either refilling the ejected fluid or ejecting a drop of fluid through the nozzle hole in the faceplate. In various other embodiments, the faceplate is made of a magnetic material, such as a ferrous material, or is coated with or connected to a magnetic material. A second primary coil or a permanent magnet may be included in various other embodiments. In various embodiments, switching the direction of the current changes the magnetic force between attraction and repulsion.

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Bernalillo, NM, United States of America

Kevin R Zavadil