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Dirk, Shawn M.

Publications and source records attributed to Dirk, Shawn M..

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Switchable antifouling coatings and uses thereof

The present invention relates to antifouling coatings capable of being switched by using heat or ultraviolet light. Prior to switching, the coating includes an onium cation component having antimicrobial and antibacterial properties. Upon switching, the coating is converted to a conjugated polymer state, and the cationic component is released with any adsorbed biofilm layer. Thus, the coatings herein have switchable and releasable properties. Methods of making and using such coatings are also described.

Denton, Michele L. Baca↗
DOE OSTI2018

Sandia National Laboratories

Sandia National Laboratories is a multimission laboratory managed by National Technology & Engineering Solutions of Sandia, LLC a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration. Sandia has a long history of pioneering AM technology development. In the mid 1990s, Sandia developed laser-engineered net shaping (LENS), one of the first direct metal AM technologies, which was commercialized by Optomec. Robocast, an extrusion-based direct-write process for 3D ceramic parts, is another technology developed at Sandia. It was commercialized by Robocast Enterprises, LLC. As of January, 2019, Sandia was conducting AM R&D projects valued at about $25 million, with an emphasis on: 1) analysis-driven design, 2) materials reliability, and 3) multi-material AM.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2017

Switchable antifouling coatings and uses thereof

The present invention relates to antifouling coatings capable of being switched by using heat or ultraviolet light. Prior to switching, the coating includes an onium cation component having antimicrobial and antibacterial properties. Upon switching, the coating is converted to a conjugated polymer state, and the cationic component is released with any adsorbed biofilm layer. Thus, the coatings herein have switchable and releasable properties. Methods of making and using such coatings are also described.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2015

Method for the electro-addressable functionalization of electrode arrays

A method for preparing an electrochemical biosensor uses bias-assisted assembly of unreactive -onium molecules on an electrode array followed by post-assembly electro-addressable conversion of the unreactive group to a chemical or biological recognition group. Electro-addressable functionalization of electrode arrays enables the multi-target electrochemical sensing of biological and chemical analytes.

42 ENGINEERING↗
DOE OSTI2015

Multifunctional thin film surface

A thin film with multiple binding functionality can be prepared on an electrode surface via consecutive electroreduction of two or more aryl-onium salts with different functional groups. This versatile and simple method for forming multifunctional surfaces provides an effective means for immobilization of diverse molecules at close proximities. The multifunctional thin film has applications in bioelectronics, molecular electronics, clinical diagnostics, and chemical and biological sensing.

47 OTHER INSTRUMENTATION↗
DOE OSTI2015

Lignin nanoparticle synthesis

A method including reducing a particle size of lignin particles to an average particle size less than 40 nanometers; after reducing the particle size, combining the lignin particles with a polymeric material; and forming a structure of the combination. A method including exposing lignin to a diazonium precursor including a functional group; modifying the lignin by introducing the functional group to the lignin; and combining the modified lignin with a polymeric material to form a composite. An apparatus including a composite of a polymer and lignin wherein the lignin has an average particle size less than 100 micrometers.

36 MATERIALS SCIENCE↗
DOE OSTI2013

Thermally switchable dielectrics

Precursor polymers to conjugated polymers, such as poly(phenylene vinylene), poly(poly(thiophene vinylene), poly(aniline vinylene), and poly(pyrrole vinylene), can be used as thermally switchable capacitor dielectrics that fail at a specific temperature due to the non-conjugated precursor polymer irreversibly switching from an insulator to the conjugated polymer, which serves as a bleed resistor. The precursor polymer is a good dielectric until it reaches a specific temperature determined by the stability of the leaving groups. Conjugation of the polymer backbone at high temperature effectively disables the capacitor, providing a `built-in` safety mechanism for electronic devices.

36 MATERIALS SCIENCE↗