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Duoss, Eric

Publications and source records attributed to Duoss, Eric.

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Micro-architected flow through electrodes for energy storage

Disclosed are electrochemical reactors with electrodes that have variable porosity across the electrode. The electrodes are designed and micro-architected to have variable porosity and 3D flow. In one aspect, an electrochemical cell apparatus is disclosed. The apparatus includes an electrochemical vessel and an electrochemical fluid contained in the electrochemical vessel. The apparatus further includes a porous electrode submerged in the electrochemical fluid in the electrochemical vessel, the porous electrode having different porosities in different areas of the porous electrode. The different porosities inhibit electrochemical fluid flow and increase electrical conductivity in first areas of the porous electrode with decreased porosity compared to second areas, and enable increased electrochemical fluid flow and decrease electrical conductivity in the second areas of the porous electrode with increased porosity compared to the first areas.

Beck, Victor Alfred↗
DOE OSTI2024

Additive manufacturing of hierarchical three- dimensional micro-architected aerogels

Disclosed here is a method for making a three-dimensional micro-architected aerogel, comprising: (a) curing a reaction mixture comprising a co-sol-gel material (e.g., graphene oxide (GO)) and at least one catalyst to obtain a crosslinked co-sol-gel (e.g., GO hydrogel); (b) providing a photoresin comprising a solvent, a photoinitiator, a crosslinkable polymer precursor, and a dispersion of the crosslinked co-sol-gel (e.g., GO hydrogel); (c) curing the photoresin using projection microstereolithography layer-by-layer to produce a wet gel having a pre-designed three-dimensional structure; (d) drying the wet gel to produce a dry gel; and (e) pyrolyzing the dry gel to produce a three-dimensional micro-architected aerogel (e.g., graphene aerogel). Also disclosed is a photoresin for projection microstereolithography, comprising a solvent, a photoinitiator, a crosslinkable polymer precursor, and a dispersion of a crosslinked co-sol-gel.

Worsley, Marcus A.↗
DOE OSTI2024

Elastomeric shape memory polymer composites

In accordance with one aspect of the presently disclosed inventive concepts, a product includes a porous three-dimensional (3D) printed polymer structure having elastomeric shape memory, where the structure includes a material comprising a plurality of gas-filled microballoons. The 3D printed polymer structure has hierarchical porosity.

Wu, Amanda↗
DOE OSTI2023

Tailored particles for powder-based additive manufacturing

The present disclosure relates to a plurality of powder particles configured to be joined in an additive manufacturing process to form a part. Each one of the powder particles has a determined three dimensional, non-spherical shape. The plurality of powder particles are further of dimensions enabling fitting individual ones of the powder particles in abutting relationship with one another. At least a subplurality of the powder particles each have a functionalized surface feature to enhance at least one of clustering or separation of the subplurality of powder particles.

Watts, Seth Evan↗
DOE OSTI2023

Three-dimensional printed porous silicone matrix using leachable porogen

The silicone-based ink for additive manufacturing includes a siloxane macromer, and a porogen mixture comprising a water-soluble porogen and a surfactant. The product of additive manufacturing with a silicone-based ink includes a three-dimensional printed structure including a plurality of continuous filaments arranged in a predefined pattern and a plurality of inter-filament pores defined by the predefined pattern of the continuous filaments. In addition, each continuous filament of the three-dimensional printed structure includes a silicone matrix having an open cell structure with a plurality of intra-filament pores, and the intra-filament pores form continuous channels through the silicone matrix.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Swab Testing Results

1. All 3D printed swabs bend to at least 90° without breaking. 2. All 3D printed swabs are at least as strong under tensile testing as their commercial counterparts. a. The Abiogenix FAST Spiral NP and EnvisionTEC swabs retain their tensile strength after sterilization and after 7 days of aging. b. For the Formlabs swabs, steam sterilization significantly reduces their tensile strength, which mostly recovers after 7 days of aging. However, the swabs are stronger than commercial ones at all times. c. The Resolution Medical Lattice swabs retain their tensile strength after 5 days of aging. Five different swab types were tested: 1. Abiogenix FAST Spiral NP Swab; 2. Formlabs NP Swab; 3. EnvisionTEC NP Swab; 4. Resolution Medical Lattice Swab; and 5. Fosun Pharma NP Swab The Abiogenix FAST Spiral NP, EnvisionTEC NP, Resolution Medical Lattice, and Fosun Pharma NP swabs were provided by their respective suppliers. The Formlabs NP swabs were printed at LLNL using the Form 3B Printer and Formlabs Surgical Guide resin

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Silicone formulations for 3D printing

In one embodiment, a silicone-based ink for additive manufacturing includes a vinyl-terminated siloxane macromer, a hydrophobic reinforcing filler, and a rheology modifying additive. In another embodiment, a method of additive manufacturing with silicone-based ink includes adding a mixture that includes a vinyl-terminated siloxane macromer, a hydrophobic reinforcing filler, and a rheology modifying additive to a cartridge for additive manufacturing, extruding the mixture through the cartridge to form a structure, and curing the mixture to at least a predefined extent.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Swab Testing Results Summary

Swabs Tested: 1. FAST Spiral NP Swab, designed and supplied by Abiogenix, printed from polyamide 11 (Nylon) using HP Multi Jet Fusion printers. 2. NP Swab designed by USF Health and Northwell Health in collaboration with Formlabs. Printed at LLNL using the Form 3B stereolithography printer in Formlabs Surgical Guide resin.

42 ENGINEERING↗
DOE OSTI2020

Swab Tensile Testing Results and Procedures - PA11 Rev. 10 Swabs

This tensile test is to mimic the worst-case scenario of the swab being caught on an obstruction when being pulled out of the nasopharyngeal space. It is to determine how much tensile force the swab can withstand without breaking. All swabs were provided by HP and were the PA11 material and Rev 10 design. All of the swabs were tested using the protocol outlined in Section 2 (Tensile Testing Procedure). Not all of the swabs were pre-treated using the Autoclave. For those swabs that were pre-treated using the Autoclave, the tensile tests were performed within 6 hours of completion of the Autoclave pre-treatment, with the exception of the “Aged” swabs. For the “Aged” swabs, the tensile tests were performed 7 days after the Autoclave pre -treatment. The “Aged” swabs that were not pre-treated using the Autoclave, were tested 7 days after those that were not “Aged.”

36 MATERIALS SCIENCE↗
DOE OSTI2020

Swab Tensile Testing Results and Procedures

This tensile test is to mimic the worst-case scenario of the swab being caught on an obstruction when being pulled out of the nasopharyngeal space. It is to determine how much tensile force the swab can withstand without breaking. A variety of different swabs (different materials and different geometries) were tested using the protocol outlined in Section 2 (Tensile Testing Procedure). Not all of the swabs were pre-treated using the Autoclave. For those swabs that were pre-treated using the Autoclave, the tensile tests were performed within 6 hours of completion of the Autoclave pre-treatment, with the exception of the “Aged” swabs. For the “Aged” swabs, the tensile tests were performed 7 days after the Autoclave pre -treatment. All swabs were provided by HP.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Swab Tensile Testing - HP Rev 10 Summary

This tensile test is to mimic the worst-case scenario of the swab being caught on an obstruction when being pulled out of the nasopharyngeal space. It is to determine how much tensile force the swab can withstand without breaking.

42 ENGINEERING↗
DOE OSTI2020

Swab Testing Results- HP PA11 Rev 8 Summary

This tensile test is to mimic the worst-case scenario of the swab being caught on an obstruction when being pulled out of the nasopharyngeal space. It is to determine how much tensile force the swab can withstand without breaking.

42 ENGINEERING↗
DOE OSTI2020

Swab Tensile Testing and Procedures

This tensile test is to mimic the worst-case scenario of the swab being caught on an obstruction when being pulled out of the nasopharyngeal space. It is to determine how much tensile force the swab can withstand without breaking. A variety of different swabs (different materials and different geometries) were tested using the protocol outlined in Section 2 (Tensile Testing Procedure). Not all of the swabs were pre-treated using the Autoclave. For those swabs that were pre-treated using the Autoclave, the tensile tests were performed within 6 hours of completion of the Autoclave pre-treatment, unless otherwise noted. The FormLabs-USF and FormLabs-Northwell were printed at LLNL using FormLabs Surgical Grade V1 Resin on a Form 3B Printer. Results Summary: All FormLabs design and treatment variations (e.g. autoclaving and “aging”) had higher tensile strength compared commercial swabs. Autoclaving degraded the tensile strength. “Aging” after autoclaving improved the tensile strength. “Aging” without autoclaving degraded the tensile strength. No differences were observed in tensile strength with different autoclaving protocols. No significant differences were observed in tensile strength for different batches.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Swab Tensile Testing Results [Slides]

HP PA11 material swabs predominantly broke at the joint between the head and the neck, although there was significant variation in the break locations. HP PA12, Injection Molded, and FormLabs (Surgical Guide V1 Resin) material swabs predominately broke in the neck region.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Swab Tensile Testing Results and Procedures

This tensile test is to mimic the worst-case scenario of the swab being caught on an obstruction when being pulled out of the nasopharyngeal space. It is to determine how much tensile force the swab can withstand without breaking. A variety of different swabs (different materials and different geometries) were tested using the protocol outlined in Section 2 (Tensile Testing Procedure). Not all of the swabs were pre-treated using the Autoclave. For those swabs that were pre-treated using the Autoclave, the tensile tests were performed within 6 hours of completion of the Autoclave pre-treatment, with the exception of the Injection Molded samples. For the Injection Molded samples, the tensile tests were performed within 24 hours of the completion of the Autoclave pre-treatment. The FormLabs-USF and FormLabs-Northwell were printed at LLNL using FormLabs Surgical Grade V1 Resin on a Form 3B Printer. All other samples were provided by HP.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Metamaterials for Mechanically Directing Cell Phenotype

Recently, abundant research has begun to reveal how microscale surface topography can influence a wide range of cell phenotypes in vitro, such as cell mobility, cell size and cell viability (Flemming et al. 1999, Nikkhah et al. 2012, Wang et al. 2016). However, while these studies shed some light on cell interactions with 2D surfaces of different length scales, cells in vivo experience their surroundings in 3D. Therefore, investigations into cell interactions with varying 3D microstructures are needed to gain biologically relevant insight into how microarchitecture and feature size influences cell behavior. Understanding this relationship between 3D microstructure and cell behavior will have a huge impact on tissue engineering and mechanobiology. Until now, the ability to fabricate complex 3D microstructures for cell behavior studies has been limited. This study harnessed LLNL’s Projection Micro-Stereolithography (PμSL) capability to probe the effects of micron-scale changes in 3D architecture on cell phenotype. Furthermore, our studies explored the application of external forces—such as cyclic loading and flow-induced shear stress—to cell-seeded 3D microstructures to further examine cell behavior.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Metal-containing photopolymer resins generated by reduction of dissolved metal salts

According to one embodiment, a three-dimensional structure includes: at least one photopolymer having at least one metal dispersed throughout at least portions of a bulk of the structure. The structure is characterized by features having a horizontal and/or vertical feature resolution in a range from several hundred nanometers to several hundred microns. The portions of the bulk throughout which metal is dispersed may optionally be selectively determined. In more embodiments, the structure may have electroless plated metal formed on surfaces thereof, alternatively or in addition to the metal dispersed throughout the bulk of the structure. The electroless plating may be achieved without the use of a surface activation bath. Corresponding methods for forming various embodiments of such three dimensional structures are also disclosed.

36 MATERIALS SCIENCE↗