Search NASA⌕ Search

SEARCH · Search NASA

Results for “encapsulated”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 451 records · Page 25

Toward Wireless Smart Grid Communications: An Evaluation of Protocol Latencies in an Open-Source 5G Testbed

Fifth-generation networks promise wide availability of wireless communication with inherent security features. The 5G standards also outline access for different applications requiring low latency, machine-to-machine communication, or mobile broadband. These networks can be advantageous to numerous applications that require widespread and diverse communications. One such application is found in smart grids. Smart grid networks, and Operational Technology (OT) networks in general, utilize a variety of communication protocols for low-latency control, data monitoring, and reporting at every level. Transitioning these network communications from wired Wide Area Networks (WANs) to wireless communication through 5G can provide additional benefits to their security and network configurability. However, introducing these wireless capabilities may also result in a degradation of network latency. In this paper, we propose utilizing 5G for smart grid communications, and we evaluate the latency impacts of encapsulating GOOSE, Modbus, and DNP3 for transmission over a 5G network. The OpenAirInterface open-source library is utilized to deploy an in-lab 5G Core Network and gNB for testing with off-the-shelf User Equipment (UE). This creates an effective 5G test platform for experimenting with different OT protocols such as GOOSE. The results are validated by measuring two different Intelligent Electronic Devices’ contact closure times for each network configuration. These tests are also conducted for varying packet sizes in order to isolate different sources of network latency. Our study outlines the latency impact of communication over 5G for time-critical and non-critical applications regarding their transition toward private 5G-based OT network implementations. The conducted experiments illustrate that in the case of GOOSE packets, simple encapsulation may exceed the protocol’s time-critical nature, and, therefore, additional measures must be taken to ensure a viable transition of GOOSE to 5G services. However, non-critical applications are shown to be viable for migration to 5G.

42 ENGINEERING↗

Discovery and characterization of a novel family of prokaryotic nanocompartments involved in sulfur metabolism

Prokaryotic nanocompartments, also known as encapsulins, are a recently discovered proteinaceous organelle-like compartment in prokaryotes that compartmentalize cargo enzymes. While initial studies have begun to elucidate the structure and physiological roles of encapsulins, bioinformatic evidence suggests that a great diversity of encapsulin nanocompartments remains unexplored. Here, we describe a novel encapsulin in the freshwater cyanobacterium Synechococcus elongatus PCC 7942. This nanocompartment is upregulated upon sulfate starvation and encapsulates a cysteine desulfurase enzyme via an N-terminal targeting sequence. Using cryo-electron microscopy, we have determined the structure of the nanocompartment complex to 2.2 Å resolution. Lastly, biochemical characterization of the complex demonstrated that the activity of the cysteine desulfurase is enhanced upon encapsulation. Taken together, our discovery, structural analysis, and enzymatic characterization of this prokaryotic nanocompartment provide a foundation for future studies seeking to understand the physiological role of this encapsulin in various bacteria.

59 BASIC BIOLOGICAL SCIENCES↗

Vaccination with mycobacterial lipid loaded nanoparticle leads to lipid antigen persistence and memory differentiation of antigen-specific T cells

Mycobacterium tuberculosis (Mtb) infection elicits both protein and lipid antigen-specific T cell responses. However, the incorporation of lipid antigens into subunit vaccine strategies and formulations has been underexplored, and the characteristics of vaccine-induced Mtb lipid-specific memory T cells have remained elusive. Mycolic acid (MA), a major lipid component of the Mtb cell wall, is presented by human CD1b molecules to unconventional T cell subsets. These MA-specific CD1b-restricted T cells have been detected in the blood and disease sites of Mtb-infected individuals, suggesting that MA is a promising lipid antigen for incorporation into multicomponent subunit vaccines. In this study, we utilized the enhanced stability of bicontinuous nanospheres (BCN) to efficiently encapsulate MA for in vivo delivery to MA-specific T cells, both alone and in combination with an immunodominant Mtb protein antigen (Ag85B). Pulmonary administration of MA-loaded BCN (MA-BCN) elicited MA-specific T cell responses in humanized CD1 transgenic mice. Simultaneous delivery of MA and Ag85B within BCN activated both MA- and Ag85B-specific T cells. Notably, pulmonary vaccination with MA-Ag85B-BCN resulted in the persistence of MA, but not Ag85B, within alveolar macrophages in the lung. Vaccination of MA-BCN through intravenous or subcutaneous route, or with attenuated Mtb likewise reproduced MA persistence. Moreover, MA-specific T cells in MA-BCN-vaccinated mice differentiated into a T follicular helper-like phenotype. Overall, the BCN platform allows for the dual encapsulation and in vivo activation of lipid and protein antigen-specific T cells and leads to persistent lipid depots that could offer long-lasting immune responses.

59 BASIC BIOLOGICAL SCIENCES↗

Glass/Glass Photovoltaic Module Reliability and Degradation: A Review - Figures

Glass/glass (G/G) photovoltaic (PV) module construction is quickly rising in popularity due to increased demand for bifacial PV modules, with additional applications for thin-film and building-integrated PV technologies. G/G modules are expected to withstand harsh environmental conditions and extend the installed module lifespan to greater than 30 years compared to conventional glass/backsheet (G/B) modules. With the rapid growth of G/G deployment, understanding the outdoor performance, degradation, and reliability of this PV module construction becomes highly valuable. In this review, we present the history of G/G modules that have existed in the field for the past 20 years, their subsequent reliability issues under different climates, and methods for accelerated testing and characterization of both cells and packaging materials. We highlight some general trends of G/G modules, such as greater degradation when using poly(ethylene-co-vinyl acetate) (EVA) encapsulants, causing the industry to move toward polyolefin-based encapsulants. Transparent backsheets have also been introduced as an alternative to the rear glass for decreasing the module weight and aiding the effusion of trapped gaseous degradation products in the laminate. New amendments to IEC 61215 standard protocols for G/G bifacial modules have also been proposed so that the rear side power generation and UV exposure will be standardized. We further summarize a suite of destructive and non-destructive characterization techniques, such as current-voltage scans, module electro-optical imaging, adhesion tests, nanoscale structural/chemical investigation, and forensic analysis, to provide deeper insights into the fundamental properties of the module materials degradation and how it can be monitored in the G/G construction. This will set the groundwork for future research and product development.

transparent backsheet↗

Graphene oxide/metal nanocrystal multilaminates the atomic limit for safe, selective hydrogen storage

Various embodiments of the invention describe an environmentally stable, and exceptionally dense hydrogen storage (6.5 wt % and 0.105 kg H2/L in the total composite, 7.56 wt % in Mg) using atomically thin and gas-selective reduced graphene oxide sheets as encapsulants. Other approaches to protecting reactive materials involve energy intensive introduction of considerable amounts of inactive, protective matrix which compromises energy density. However, these multilaminates are able to deliver exceptionally dense hydrogen storage far-exceeding 2020 DOE target metrics for gravimetric capacity (5.5 wt %), and ultimate full-fleet volumetric targets (0.070 kg H 2 /L) for fuel cell electric vehicles. Methods of stabilizing reactive nanocrystalline metals in zero-valency also has wide-ranging applications for batteries, catalysis, encapsulants, and energetic materials.

Urban, Jeffrey J.↗

In vitro assembly of bacterial microcompartments

The present disclosure is related to a BMC fusion protein that is capable of in vitro assembly, comprising a constituent BMC shell protein subunit and a sterically hindering protein domain that is cleavable. The BMC fusion protein is capable of in vitro assembly triggered by removal of the fused sterically hindering domain. The present disclosure is also related to a means to produce BMC shells in vitro, triggered by removal of a fused sterically hindering domain from one or more constituent BMC shell protein subunits. The BMC fusion protein enables encapsulation of broad classes of materials and biophysical studies of shell assembly, encapsulation, and permeability that would otherwise be unavailable from BMCs assembled in vivo.

Hagen, Andrew Ronald↗

Field Reliability of Glass/Glass Modules

A review of literature indicates that there will be a 20% increase in utilization of glass/glass PV modules by 2023. Common degradation modes reported in literature of glass/glass modules are: Encapsulant delamination, Encapsulant browning, corrosion and glass cracks. There is a strong need to investigate the reliability of glass/glass modules in detail to identify and overcome any potential failures in the future constructions. This work presents a preliminary literature review on the reliability of old generation glass/glass modules in the field.

14 SOLAR ENERGY↗

Silicon sealing for high performance battery anode materials

A battery electrode is provided that includes a porous silicon microstructure precursor, a silicon shell coating deposited on the silicon microstructure precursor, and a graphene coating deposited on the silicon shell coating, where the graphene coating encapsulates the silicon shell coating forming a graphene-encapsulated silicon-shell-protected porous silicon microstructure precursor battery electrode.

Cui, Yi↗

Integrated Thermal Energy Storage System for Air-Conditioners with Phase-Change Composites

Thermal energy storage (TES) is a promising solution to store and dispatch energy and shave peak electric load, reducing the operational cost of HVAC systems. We present results of a TES system using phase-change materials (PCM) integrated with an air conditioner. The proposed system uses an organic PCM (tetradecane) encapsulated within compressed expanded natural graphite foams referred to as phase-change composite. The graphite foam encapsulates the PCM eliminating the need for expensive storage vessels, reduces installation costs, and provides higher thermal conductivity that can lead to faster charge/discharge rates. Two serpentines, multi-pass circuits, operating as a heat source and a sink, exchange heat to and from the phase-change composite. These two circuits are embedded in multiple slabs of this material. The "charge" circuit contains the refrigerant that is directly coupled to a vapor compression system, and the "discharge" circuit removes heat from an airstream and releases it into the PCM composite through a water-glycol liquid coupling. This configuration allows for multiple modes of operation depending on the state of charge of the thermal energy storage module, the building air-conditioning load, and the current electricity and demand charges. This flexible operation allows variable air volume capacity control without the need to have a variable capacity refrigeration system. We developed a 21 kW-hr (6 RT-hr) prototype TES system coupled with a commercial air-conditioner to characterize the component-and system-level performance.

air-conditioning↗

Metal nanoparticles as lubricant additives

A lubricant composition comprising: (i) silver or gold nanoparticles, each of which is encapsulated by a layer of alkylthiol or alkylamine molecules; (ii) palladium or platinum nanoparticles, each of which is encapsulated by a layer of alkylthiol or alkylamine molecules; and (iii) a fluid in which components (i) and (ii) are present. Further described are methods for applying the lubricant composition onto a mechanical device for which lubrication is beneficial, with resulting improvement in friction and wear reduction and/or corrosion inhibition.

Ihala Gamaralalage, Chanaka Kapila Kumara↗

Evaluation of Bifacial Modules and PV Technologies with Combined-Accelerated Stress Testing

In view of the increasing interest and market share of bifacial cells and modules, suitable substrates such as glass and transparent backsheets along with ethylene vinyl acetate (EVA) and polyolefin elastomer (POE) encapsulants were examined in combined-accelerated stress testing (C-AST) to evaluate and compare degradation modes. Testing with both monofacial and bifacial cells, we found glass-glass modules with monofacial cells led to greater grid finger breakage than those with polymeric backsheets. This is attributed to previous x-ray topography work showing higher stress in cells in glass-glass modules than glass backsheet modules. Consistent with the objectives of C-AST, which stresses modules at levels corresponding to the limits seen in the natural environment, we observed the UV-fluorescence signatures of modules tested in C-AST (considering the degradation associated with developing chromophores, moisture penetration and photobleaching effects) to be like those in fielded modules, more so than other chamber stress testing implemented for comparison. Finally, among multiple cell degradation modes that we observed such as light-induced degradation (LID), we differentiated susceptibility to potential-induced degradation (PID) on the back of the bifacial Passivated Emitter Back Cells (PERC) in C-AST. Confirming with ex-situ tests, we found polarization-type PID most prevalent in glass/glass modules with EVA as would be anticipated considering the greater leakage current through such module encapsulation. Unlike PID tests performed in the dark, which can lead to false positive PID test results, field-representative illumination is experienced by the modules on the front and back side while -1200 V system voltage is applied in C-AST, supporting the conclusion that this module type would be susceptible to PID in the field.

bifacial modules↗

Carbon-based volatile and non-volatile memristors

An ultrathin, carbon-based memristor with a moiré superlattice potential shows prominent ferroelectric resistance switching. The memristor includes a bilayer material, such as Bernal-stacked bilayer graphene, encapsulated between two layers of a layered material, such as hexagonal boron nitride. At least one of the encapsulating layers is rotationally aligned with the bilayer to create the moiré superlattice potential. The memristor exhibits ultrafast and robust resistance switching between multiple resistance states at high temperatures. The memristor, which may be volatile or nonvolatile, may be suitable for neuromorphic computing.

Jarillo-Herrero, Pablo↗

Solar mirrors and methods of making solar mirrors having improved properties

An article for reflecting solar energy includes a coating stack having solar reflecting films and metal oxide films, the coating stack applied on a major surface of a glass substrate, and a protective overcoat comprising a first and a second surface, wherein the first surface of the protective overcoat is disposed toward the solar reflective films and metal oxide films; and a polymer encapsulant over outer wall surfaces of the coating stack, the second surface of the protective overcoat and over peripheral edges of the coated article, the encapsulant having a base layer, a top layer and metallic corrosion-inhibitive material in the base layer.

14 SOLAR ENERGY↗

Wavelength-selective specularly reflecting photovoltaic module and manufacture thereof

A photovoltaic module comprises a plurality of photovoltaic cells, and a polymeric film positioned on an incident light side of the plurality of photovoltaic cells, wherein the polymeric film transmits a range of wavelengths of the incident light spectrum and specularly reflects wavelengths outside of the range. An encapsulant layer is in contact with the polymeric film. The polymeric film may have a first surface area larger than a second surface area of the layer of photovoltaic cells. The polymeric film may have one or more through-holes so that encapsulant can penetrate through the through-holes at elevated temperature during lamination thereby bonding to a front glass of the photovoltaic module.

14 SOLAR ENERGY↗

Electronic and Optical Properties of NV Center in Diamonds for Sensing Applications: Experimental and First Principles Density Functional Theory Approach

The nitrogen-vacancy (NV) center in a nanodiamond (ND) crystal is one of the best candidate materials for quantum sensing and metrology applications at elevated environmental conditions. The NV center can be used to achieve an unprecedented level of sensitivity for sensing applications at high temperatures and pressures. The NV center is also proven to be useful for magnetic field sensing. Furthermore, it can be used for applications in the sensing of valuable minerals such as rare earth elements (REEs) from the crude and waste subsurface materials. This work presents computational and experimental studies on electronic and optical properties of bulk diamond with N and NV defects. ND in MOF/polymer materials will be experimentally encapsulated. The transverse spin relaxation time of the NV center will be measured in bare and encapsulated ND. Different doping elements will be introduced on the surfaces and present surface electronic properties to study the surfaces with shallow NV center for quantum sensing applications.

Paudel, Hari P.↗

Isolated data processing modules

This disclosure relates to computer systems that isolate data processing modules and methods of operating the same. In one embodiment of a method, a computer system receives a first data processing request for a first data file. The computer system may determine that a first data type of the first data file is supported by an encapsulated data processing module and determine a first communication protocol from a set of communication protocols that can be used to receive the first data file. The computer system can then receive the first data file from the first storage location in accordance with the first communication protocol and the encapsulated data processing module may be executed to convert the first data file in the first data format into second data in a second data format.

Penton, Joshua Michael↗

Crosslinked polymers with tunable coefficients of thermal expansion

Curatives and their resulting thermosets and other crosslinked polymers can reduce thermal expansion mismatch between an encapsulant and objects that are encapsulated. This can be accomplished by incorporating a negative CTE moiety into the thermoset resin or polymer backbone. The negative CTE moiety can be a thermal contractile unit that shrinks as a result of thermally induced conversion from a twist-boat to chair or cis/trans isomerization upon heating. Beyond CTE matching, other potential uses for these crosslinked polymers and thermosets include passive energy generation, energy absorption at high strain rates, mechanophores, actuators, and piezoelectric applications.

Redline, Erica Marie↗

Overview of Quantum Sensing Materials and Techniques for Energy Sector Applications

The energy sector has become increasingly dependent upon highly sensitive sensing devices for a wide range of applications. Variables such as temperature, pH, electromagnetic fields, ions, and pressure must be measured with high precision, often in harsh conditions (e.g. highly corrosive environments due to high temperature, pressure and humidity). These sensors are deployed in infrastructure such as transformers, pipelines, mines, nuclear power plants, and other areas to ensure safe operating conditions and uninterrupted, optimized service. Moreover, new opportunities for sensors have emerged due to the expansion of smart grids/meters, driverless vehicles, and the discovery of new oil, gas, and critical mineral deposits. The continued maturation of quantum sensing technologies offers exciting opportunities for quantum-enhanced measurements within the energy sector that may provide significant improvements in sensitivity beyond the classical limit. Here, an overview of established and emerging quantum materials for sensing applications will be provided, from trapped ions to color centers in diamond and silicon carbide. Associated quantum sensing methods for these materials will be discussed, with an emphasis on platforms that are nearing commercial viability. Specific application opportunities within the energy sector for quantum sensors will then be analyzed, including oil/gas discovery, greenhouse gas emission monitoring, pH and ion sensing, current measurement in electric vehicle batteries, and quantum-enhanced spectroscopy. Remaining barriers, such as quantum sensor platform miniaturization and ruggedization, will also be analyzed. A specific project at the National Energy Technology Laboratory involving the functionalization of qubits using metal-organic frameworks for enhanced quantum sensing will also be highlighted. Here, nitrogen vacancy centers (NV) in nanodiamonds, a commercially available qubit with long coherence times and utilizable quantum properties at room temperature, are encapsulated in a controlled way using the metal-organic framework ZIF-8. The ZIF-8 provides a well-defined, porous scaffold that can be controlled to promote the selective uptake of specific target analytes, such as gas molecules or ions. The quantum sensing performance of this composite material is either preserved or enhanced following ZIF-8 encapsulation; the optically detected magnetic resonance response of the NV nanodiamonds with and without the ZIF-8 coating are identical, while the ZIF-8 coating increases the longitudinal spin relaxation lifetime (T1) of the NV centers, an important parameter for spin relaxometry-based quantum sensing experiments. Taken together, these results demonstrate the importance of qubit functionalization as a crucial step for rationally designing high performance quantum sensors.

Crawford, Scott↗