Encapsulation, Electronics, Eccofoam
Polyurethane foam and casting resin for encapsulation, reinforcement, and sealing electronic equipment
REINFORCEMENT↗
SEARCH · Engineering Papers
Results for “ENCAPSULATION”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Fabrication and encapsulation of transistors and computation of voltage capability and current gain Second quarterly report, Oct. - Dec. 1965
Fabrication and encapsulation of epitaxial surface transistor
EPITAXIAL DEPOSITION↗
Design guide for use of polyurethane foam as an encapsulant for high voltage devices
Design guide for use of polyurethane foam as encapsulant for high voltage devices in space environment
ENCAPSULATION↗
Plastic Encapsulated Microcircuits (PEMs) Reliability Guide
It is reported by some users and has been demonstrated by others via testing and qualification that the quality and reliability of plastic-encapsulated microcircuits (PEMs) manufactured today are excellent in commercial applications and closely equivalent, and in some cases superior to their hemetic counterparts.
plastic encapsulated microcircuits reliability gui↗
Building America Top Innovations 2013 Profile – Buried and Encapsulated Ducts
In this innovation profile, CARB research shows HVAC ducts that are encapsulated in closed-cell spray foam and buried in blown insulation in a vented attic meet the code requirements for ducts in conditioned space.
BEDs↗
Degradation in PV Encapsulation Strength of Attachment: An Interlaboratory Study Towards a Climate-Specific Test
Reduced strength of attachment of the encapsulant resulting from the outdoor environment, including ultraviolet (UV) radiation, may decrease photovoltaic (PV) module lifetime by enabling widespread corrosion of internal components. To date, few studies exist showing how the adhesion of PV components varies with environmental stress. We have conducted an interlaboratory experiment to provide an understanding that will be used to develop climatic specific module tests. Factors examined in the study included the UV light source (lamp type), temperature, and humidity to be proposed for use in accelerated aging tests. A poly (ethylene-co-vinyl acetate) (EVA) formulation often used in veteran PV installations was studied using a compressive shear test - to quantify the strength of attachment at the EVA/glass interface. Replicate laminated glass/polymer/glass coupon specimens were weathered at 12 institutions using a variety of indoor chambers or field aging. Shear strength, shear strain, and toughness were measured using a mechanical load-frame for the compressive shear test, with subsequent optical imaging and electron microscopy of the separated surfaces.
14 SOLAR ENERGY↗
Hybrid Encapsulated Ionic Liquids for Post-Combustion Carbon Dioxide (CO2) Capture
Presentation of Summary of Progress for the NETL Sponsored project, "Hybrid Encapsulated Ionic Liquids for Post- Combustion Carbon Dioxide (CO2) Capture." Presented at annual CO2 Capture Review, NETL, Pittsburgh, August 14, 2018
20 FOSSIL-FUELED POWER PLANTS↗
Macro-encapsulation as Manufactured Components for Disposal at the Nevada National Security Site (NNSS) - 16213
Macro-encapsulation as Manufactured is a relatively new terminology that supports the disposal of classified legacy weapon components at the Area 5 Disposal Cell at the Nevada National Security Site (NNSS). These components are composed of hundreds and sometimes thousands of parts. Examples of this type of item include firing sets, trainers, radar assemblies, neutron generators and other similar components. Sometimes there are hazardous Resource Conservation and Recovery Act-regulated (RCRA) metals involved in the parts that make up the components. The typical regulated metals in the components can be lead and silver from circuit boards and wiring, cadmium or chromium from plating operations of the parts. To perform the Toxicity Characteristic Leaching Procedure (TCLP) components have to be completely disassembled and sanitized prior to being sent to laboratories for analysis. The results vary but the majority of times there are regulated metals present in these samples. The levels are relatively low and since analysis has been performed then a disposal process needs to be followed. A process needed to be developed and approved by governing boards to allow disposal of these items as long as this material meets the Waste Acceptance Criteria (WAC) (No liquids, compressed gases, explosives, SNM, etc.) before being sent to the Nevada desert for disposal. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Revision of the Branch Technical Position on Concentration Averaging and Encapsulation - 16315
On February 25, 2015, the U.S. Nuclear Regulatory Commission (NRC) issued Revision 1 of the Branch Technical Position on Concentration Averaging and Encapsulation (CA BTP), culminating a six-year process. This revision provides updated guidance on the interpretation of paragraph 61.55(a)(8) of Title 10 of the Code of Federal Regulations, 'Determination of concentrations in wastes', as it applies to the classification of a variety of different types and forms of low-level radioactive waste (LLW) as Class A, B, or C waste. The waste class determines the minimum safety measures to be applied in order to provide reasonable assurance of safe disposal of the waste. The CA BTP is used by thousands of LLW generators, by the waste processing industry, by all operating LLW disposal sites in the U.S. and by Agreement States. The previous version of the CA BTP, published in 1995, was issued before the NRC adopted its risk-informed and performance-based regulatory policy. The revised CA BTP has been informed by that policy. The revised CA BTP also contains new guidance on acceptable methods that can be used to perform concentration averaging of LLW for the purpose of determining its waste class for disposal. This paper provides background information on why the CA BTP was issued and subsequently updated. This paper summarizes the new guidance found in the revised CA BTP. This paper also explains some of the key issues that required NRC's resolution, and the reasoning that underpins the major decisions reflected in Revision 1 of the CA BTP. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Waste Encapsulation and Storage Facility Stabilization and Ventilation Project-18121
Department of Energy contractor CH2M HILL Plateau Remediation Company (CH2M) is responsible for the safe and compliant operation of the Waste Encapsulation and Storage Facility (WESF), a nuclear materials storage facility at Hanford containing 1,936 highly radioactive capsules containing cesium and strontium. The capsules are currently stored under approximately 4 m (13 ft) of water. The water shields workers from radiation and helps cool the capsules. WESF is a large, concrete structure nominally 48 m (160 ft) long, 30 m (98 ft) wide and 12 m (40 ft) high with the pool cells being approximately 4 m (13 ft) below grade level. It is a robust facility with walls ranging from 0.3 m to 1 m (1 ft to 3 ft) thick. While the capsules are currently in a safe configuration, WESF is an aging facility, and DOE and CH2M are modifying the facility to ensure continued safe and compliant operations and to support the eventual transfer of capsules to dry storage. Dry storage would eliminate the possibility of a release of radioactive material in the unlikely event of a major earthquake that might result in loss of pool storage water and overheating and breach of one or more capsules. The project was divided into two major deliverables: 1) Ventilation: replacement of the existing ventilation system which included a below-grade high efficiency particulate air (HEPA) filter pit with an above grade HEPA filter skid and new fans and ducting. 2) Stabilization: grouting deactivated facility hot cells and other void spaces to the maximum extent practical to reduce material at risk from legacy contamination. The aging ventilation system relied on HEPA filters that exceeded their operational life. Due to the high levels of radionuclide contamination, replacing the filters was impractical and highly hazardous. CH2M installed a new ventilation system to provide safe and compliant ventilation for future operations. The project used an existing, unused ventilation skid that was designed for another project. Repurposing the unused skid presented additional technical challenges to modify the system for the project specific requirements. The new system is above ground, easier to maintain and is built to current standards. New connections inside the facility were installed to allow the new ventilation to operate effectively. The stabilization project is unique in that core drilling and grouting was performed in an operating Hazard Category 2 nuclear facility, which brought forth safety basis and environmental regulatory challenges. The hot cells were isolated from all existing support utilities including electrical, process chemicals, manipulator ports, instrument air, etc. to seal the hot cells and prevent highly contaminated supernate or grout from leaking into adjacent galleries. A high flow grout was used to maximize the distance between injection ports. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Encapsulation of Wastes Using Adapted Geopolymer Formulations - 20272
A geopolymer formulation characterized by a low initial viscosity, suitable to immobilise a wide range of waste types such as oils, chemicals and solid waste, is introduced and characterized. The role of the specific surface area of magnesium oxide additions to the reference formulation is presented. Moreover, its capability to encapsulate different volume fractions of oil via the preparation of oil in activator solution emulsions is introduced. Lastly, the effect of oil incorporation on the density, the mechanical strength and the leaching properties of the compositions is presented and discussed. (authors)
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Dendrimer-Encapsulated Ruthenium Nanoparticles as Catalysts for Lithium-O2 Batteries
Dendrimer-encapsulated ruthenium nanoparticles (DEN-Ru) have been used as catalysts in lithium-O2 batteries for the first time. Results obtained from UV-vis spectroscopy, electron microscopy and X-ray photoelectron spectroscopy show that the nanoparticles synthesized by the dendrimer template method are ruthenium oxide instead of metallic ruthenium reported earlier by other groups. The DEN-Ru significantly improve the cycling stability of lithium (Li)-O2 batteries with carbon black electrodes and decrease the charging potential even at low catalyst loading. The monodispersity, porosity and large number of surface functionalities of the dendrimer template prevent the aggregation of the ruthenium nanoparticles making their entire surface area available for catalysis. The potential of using DEN-Ru as stand-alone cathode materials for Li-O2 batteries is also explored.
Environmental Molecular Sciences Laboratory↗
Encapsulation of Nanoparticle Organic Hybrid Materials within Electrospun Hydrophobic Polymer/Ceramic Fibers for Enhanced CO 2 Capture
Liquid-like nanoparticle organic hybrid materials (NOHMs) consisting of a silica core with ionically grafted branched polyethyleneimine chains (referred to as NIPEI) are encapsulated within submicron-scale polyacrylonitrile (PAN)/polymer-derived-ceramic electrospun fibers. The addition of a room-temperature curable, liquid-phase organopolysilazane (OPSZ) ceramic precursor to the PAN/NOHM solution enhances the internal dispersion of NOHMs and forms a thin ceramic sheath layer on the fiber exterior, shielding the hydrophilic NIPEI to produce near-superhydrophobic non-woven fiber mats with contact angles exceeding 140°. 60:40 loadings of NOHMs to PAN/OPSZ can be reliably achieved with low OPSZ percentages required, and up to 4:1 NOHM:polymer loadings are possible before losing hydrophobicity. These fibers demonstrate up to ≈2 mmol CO 2 g -1 fiber capture capacities in a pure CO 2 atmosphere through the nonwoven fibrous networks and the permeability of the OPSZ shell. In conclusion, the hybrid fibers additionally show enhanced capture kinetics under pure CO 2 and 400 ppm CO 2 conditions, indicating their promising application as a direct air capture platform.
36 MATERIALS SCIENCE↗
Graphitic‐Shell Encapsulation of Metal Electrocatalysts for Oxygen Evolution, Oxygen Reduction, and Hydrogen Evolution in Alkaline Solution
Abstract Developing highly efficient, cost effective, and environmentally friendly electrocatalysts for the oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and hydrogen evolution reaction (HER) is of interest for sustainable and clean energy technologies, including metal–air batteries and fuel cells. In this work, the screening of electrocatalytic activities of a series of single metallic iron, cobalt, and nickel nanoparticles and their binary and ternary alloys encapsulated in a graphitic carbon shell toward the OER, ORR, and HER in alkaline media is reported. Synthesis of these compounds proceeds by a two‐step sol–gel and carbothermal reduction procedure. Various ex situ characterizations show that with harsh electrochemical activation, the graphitic shell undergoes an electrochemical exfoliation. The modified electronic properties of the remaining graphene layers prevent their exfoliation, protect the bulk of the metallic cores, and participate in the electrocatalysis. The amount of near‐surface, higher‐oxidation‐state metals in the as‐prepared samples increases with electrochemical cycling, indicating that some metallic nanoparticles are not adequately encased within the graphite shell. Such surface oxide species provide secondary active sites for the electrocatalytic activities. The Ni–Fe binary system gives the most promising results for the OER, and the Co–Fe binary system shows the most promise for the ORR and HER.
Khani, Hadi↗
Encapsulation of a Cr III Single‐Ion Magnet within an Fe II Spin‐Crossover Supramolecular Host
Abstract Single functional molecules are regarded as future components of nanoscale spintronic devices. Supramolecular coordination chemistry provides unlimited resources to implement multiple functions to individual molecules. A novel coordination [Fe 2 ] helicate exhibiting spin‐crossover is demonstrated to be ideally suited to encapsulate a [Cr(ox) 3 ] 3− complex anion (ox=oxalate), unveiling for the first‐time single ion slow relaxation of the magnetization for this metal. A possibility of tuning the dynamics of this relaxation as well as the performance of the Cr III center as qubit arises from the observation that metastable high spin Fe II centers from the host can be generated by irradiation with green light at low temperature.
Darawsheh, Mohanad↗
Enhanced Drug Delivery by Dissolution of Amorphous Drug Encapsulated in a Water Unstable Metal–Organic Framework (MOF)
Abstract Encapsulating a drug molecule into a water‐reactive metal–organic framework (MOF) leads to amorphous drug confined within the nanoscale pores. Rapid release of drug occurs upon hydrolytic decomposition of MOF in dissolution media. Application to improve dissolution and solubility for the hydrophobic small drug molecules curcumin, sulindac, and triamterene is demonstrated. The drug@MOF composites exhibit significantly enhanced dissolution and achieves high supersaturation in simulated gastric and/or phosphate buffer saline media. This combination strategy where MOF inhibits crystallization of the amorphous phase and then releases drug upon MOF irreversible structural collapse represents a novel and generalizable approach for drug delivery of poorly soluble compounds while overcoming the traditional weakness of amorphous drug delivery: physical instability of the amorphous form.
Suresh, Kuthuru↗
Atomically Dispersed Nickel(I) on an Alloy‐Encapsulated Nitrogen‐Doped Carbon Nanotube Array for High‐Performance Electrochemical CO 2 Reduction Reaction
Abstract Single‐atom catalysts (SACs) show great promise for electrochemical CO 2 reduction reaction (CRR), but the low density of active sites and the poor electrical conduction and mass transport of the single‐atom electrode greatly limit their performance. Herein, we prepared a nickel single‐atom electrode consisting of isolated, high‐density and low‐valent nickel(I) sites anchored on a self‐standing N‐doped carbon nanotube array with nickel–copper alloy encapsulation on a carbon‐fiber paper. The combination of single‐atom nickel(I) sites and self‐standing array structure gives rise to an excellent electrocatalytic CO 2 reduction performance. The introduction of copper tunes the d‐band electron configuration and enhances the adsorption of hydrogen, which impedes the hydrogen evolution reaction. The single‐nickel‐atom electrode exhibits a specific current density of −32.87 mA cm −2 and turnover frequency of 1962 h −1 at a mild overpotential of 620 mV for CO formation with 97 % Faradic efficiency.
Zhang, Tianyu↗
Encapsulation of a Cr III Single‐Ion Magnet within an Fe II Spin‐Crossover Supramolecular Host
Abstract Single functional molecules are regarded as future components of nanoscale spintronic devices. Supramolecular coordination chemistry provides unlimited resources to implement multiple functions to individual molecules. A novel coordination [Fe 2 ] helicate exhibiting spin‐crossover is demonstrated to be ideally suited to encapsulate a [Cr(ox) 3 ] 3− complex anion (ox=oxalate), unveiling for the first‐time single ion slow relaxation of the magnetization for this metal. A possibility of tuning the dynamics of this relaxation as well as the performance of the Cr III center as qubit arises from the observation that metastable high spin Fe II centers from the host can be generated by irradiation with green light at low temperature.
Darawsheh, Mohanad↗