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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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At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

YAP/TAZ Related BioMechano Signal Transduction and Cancer Metastasis

Mechanoreciprocity refers to a cell’s ability to maintain tensional homeostasis in response to various types of forces. Physical forces are continually being exerted upon cells of various tissue types, even those considered static, such as the brain. Through mechanoreceptors, cells sense and subsequently respond to these stimuli. These forces and their respective cellular responses are prevalent in regulating everything from embryogenic tissue-specific differentiation, programmed cell death, and disease progression, the last of which being the subject of extensive attention. Abnormal mechanical remodeling of cells can provide clues as to the pathological status of tissues. This becomes particularly important in cancer cells, where cellular stiffness has been recently accepted as a novel biomarker for cancer metastasis. Several studies have also elucidated the importance of cell stiffness in cancer metastasis, with data highlighting that a reversal of tumor stiffness has the capacity to revert the metastatic properties of cancer. In this review, we summarize our current understanding of extracellular matrix (ECM) homeostasis, which plays a prominent role in tissue mechanics. We also describe pathological disruption of the ECM, and the subsequent implications toward cancer and cancer metastasis. In addition, we highlight the most novel approaches toward understanding the mechanisms which generate pathogenic cell stiffness and provide potential new strategies which have the capacity to advance our understanding of one of human-kinds’ most clinically significant medical pathologies. These new strategies include video-based techniques for structural dynamics, which have shown great potential for identifying full-field, high-resolution modal properties, in this case, as a novel application.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2026

Achieving Phase Control of Polymorphic Tungsten Carbide Catalysts

The polymorphism of tungsten carbide (W x C) and the challenge of selectively synthesizing pure phases have impeded a precise understanding of catalytic structure−property relationships. This study establishes a framework for phase-selective synthesis of W x C through controlling carburization kinetics. By maintaining particle sizes below 10 nm, β-W 2 C is selectively synthesized using gaseous carbon precursors (CH 4 /H 2 ) via temperature-programmed carburization (TPC). Our findings reveal that W 2 C stabilization is predominantly dictated by particle size and carburization kinetics rather than support interactions, providing a tunable approach to synthesize tungsten carbide catalysts. We elucidate the mechanistic pathway of WO x carburization, demonstrating that CH 4 activation occurs at mild temperatures via lattice oxygen. Our reactor studies establish ex situ synthesized β- W 2 C as an active and stable catalyst for the reverse water-gas shift (RWGS) reaction. However, the need for passivation and reduction pretreatment leads to a complex surface structure with diminished intrinsic activity. In contrast, our in situ synthesis protocol for β-W 2 C eliminates the need for passivation and exhibits increased CO STY during RWGS, illustrating the intrinsically higher activity compared to metallic W, WC 1−x (0.5 < x < 1), and stoichiometric WC.

CO2 conversion↗
DOE OSTI2024

Discovering neutrino tridents at the Large Hadron Collider

Neutrino trident production of dilepton pairs is well recognized as a sensitive probe of both electroweak physics and physics beyond the Standard Model. Although a rare process, it could be significantly boosted by such new physics, and it also allows the electroweak theory to be tested in a new regime. We demonstrate that the forward neutrino physics program at the Large Hadron Collider offers a promising opportunity to measure for the first time, dimuon neutrino tridents with a statistical significance exceeding 5 σ , improving on the previous claims at the ∼ 3 σ level by the CHARM-II and CCFR collaborations while accounting for additional backgrounds later identified by the NuTeV collaboration. We present predictions for various proposed experiments and outline a specific experimental strategy to identify the signal and mitigate backgrounds, based on “reverse tracking” dimuon pairs in the FASER ν 2 detector. We also discuss prospects for constraining beyond Standard Model contributions to neutrino trident rates at high energies. Published by the American Physical Society 2024

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2024

Inhibition of the eukaryotic initiation factor-2α kinase PERK decreases risk of autoimmune diabetes in mice

Preventing the onset of autoimmune type 1 diabetes (T1D) is feasible through pharmacological interventions that target molecular stress–responsive mechanisms. Cellular stresses, such as nutrient deficiency, viral infection, or unfolded proteins, trigger the integrated stress response (ISR), which curtails protein synthesis by phosphorylating eukaryotic translation initiation factor-2α (eIF2α). In T1D, maladaptive unfolded protein response (UPR) in insulin-producing β cells renders these cells susceptible to autoimmunity. We found that inhibition of the eIF2α kinase PKR-like ER kinase (PERK), a common component of the UPR and ISR, reversed the mRNA translation block in stressed human islets and delayed the onset of diabetes, reduced islet inflammation, and preserved β cell mass in T1D-susceptible mice. Single-cell RNA-Seq of islets from PERK-inhibited mice showed reductions in the UPR and PERK signaling pathways and alterations in antigen-processing and presentation pathways in β cells. Spatial proteomics of islets from these mice showed an increase in the immune checkpoint protein programmed death-ligand 1 (PD-L1) in β cells. Golgi membrane protein 1, whose levels increased following PERK inhibition in human islets and EndoC-βH1 human β cells, interacted with and stabilized PD-L1. Collectively, our studies show that PERK activity enhances β cell immunogenicity and that inhibition of PERK may offer a strategy for preventing or delaying the development of T1D.

Research & Experimental Medicine↗
DOE OSTI2023

CRISPR/Cas9 Directed Reprogramming of iPSC for Accelerated Motor Neuron Differentiation Leads to Dysregulation of Neuronal Fate Patterning and Function

Neurodegeneration causes a significant disease burden and there are few therapeutic interventions available for reversing or slowing the disease progression. Induced pluripotent stem cells (iPSCs) hold significant potential since they are sourced from adult tissue and have the capacity to be differentiated into numerous cell lineages, including motor neurons. This differentiation process traditionally relies on cell lineage patterning factors to be supplied in the differentiation media. Genetic engineering of iPSC with the introduction of recombinant master regulators of motor neuron (MN) differentiation has the potential to shorten and streamline cell developmental programs. We have established stable iPSC cell lines with transient induction of exogenous LHX3 and ISL1 from the Tet-activator regulatory region and have demonstrated that induction of the transgenes is not sufficient for the development of mature MNs in the absence of neuron patterning factors. Comparative global transcriptome analysis of MN development from native and Lhx-ISL1 modified iPSC cultures demonstrated that the genetic manipulation helped to streamline the neuronal patterning process. However, leaky gene expression of the exogenous MN master regulators in iPSC resulted in the premature activation of genetic pathways characteristic of the mature MN function. Dysregulation of metabolic and regulatory pathways within the developmental process affected the MN electrophysiological responses.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2018

Adsorption and decomposition of dimethyl methylphosphonate on size-selected (MoO 3 ) 3 clusters

The adsorption and decomposition of dimethyl methylphosphonate (DMMP), a chemical warfare agent (CWA) simulant, on size-selected molybdenum oxide trimer clusters, i.e. (MoO3)3, was studied both experimentally and theoretically. X-ray photoelectron spectroscopy (XPS), temperature programmed reaction (TPR), and density functional theory (DFT)-based simulations were utilized in this study. The XPS and TPR results showed both, desorption of intact DMMP, and decomposition of DMMP through the elimination of methanol at elevated temperatures on (MoO3)3 clusters. Theoretical investigation of DMMP on (MoO3)3 clusters suggested that, in addition to pure (MoO3)3 clusters, reduced molybdenum oxide clusters and hydroxylated molybdenum oxide clusters also play an important role in decomposing DMMP via a “reverse Mars–van Krevelen mechanism”. The present study, which focused on oxide clusters, underlines the importance of surface defects, e.g., the oxygen vacancies and surface hydroxyls, in determining the reaction pathway of DMMP, in agreement with previous studies on thin films. In addition, the structural fluxionality and the Lewis acidity of molybdenum oxide clusters, i.e. (MoO3)3, may make them good candidates for adsorption and decomposition of chemical warfare agents with similar structures to DMMP.

Tang, Xin↗
DOE OSTI2019

Carbon Life Cycle Analysis of CO 2 -EOR for Net Carbon Negative Oil (NCNO) Classification (Final Report)

This final report summarizes the work that was conducted to achieve the project’s general objective of developing a clear and repeatable methodology to determine whether the oil produced in a conventional CO 2 enhanced oil recovery (CO 2 -EOR) operation can be classified as Net Carbon Negative Oil (NCNO). The report also summarizes the reservoir mass accounting methodology and the monitoring, verification, and accounting (MVA) methodology, which are critical elements that support the general objective and were conceived as project goals. Because the purpose is to classify the EOR product (crude oil) and not the EOR project itself, and as the rate of crude oil production varies significantly with time, the methodology uses a novel dynamic carbon lifecycle analysis (d-LCA) that links instant energy demand and associated greenhouse gas (GHG) emissions to instant operational performance. The EOR operational performance is assessed through CO 2 utilization rates, which relate usage of CO 2 to oil production This dynamic method provides a better understanding of the evolution of the environmental impact (CO 2 emissions) and mitigation (geologic CO 2 storage) associated with an expanded carbon capture, utilization and storage (CCUS) system, from start to closure of operations. The dynamic interplay between operational and environmental performance forms the basis of our CCUS technology analysis. The LCA part of the work is meant to complement previous NETL LCA work, and so it focused on EOR/storage efficiency, its variability through time, and the impact of this variability on LCA results. The environmental impact of the CCUS system was assessed for 3 system boundaries: (1) gate-to-gate, (2) gate-to-grave, and (3) cradle-to-grave. The environmental impact was also assessed considering the electricity displacement from other generation facilities. Another goal of our study was to use results to make recommendations on EOR field development strategies that are conducive to producing NCNO. Because field operational strategies have a significant impact on reservoir engineering parameters that affect both CO 2 storage and oil production (e.g., sweep efficiency, flood conformance, fluid saturation distribution), we conducted a scenario analysis that assesses the operational and environmental performance of four common and novel CO 2 -EOR field development strategies. Results show that all CO 2 -EOR evaluated scenarios start operating with a negative carbon footprint and, years into the project, transition into operating with a positive carbon footprint. Having achieved a result that proves that all CO 2 -EOR operations produce NCNO during the first years of production is critical in the context of the urgency of climate change mitigation. Transition points are significantly different in each scenario. ii In a cradle-to-grave CCUS system, if the capture facility displaces a conventional power source and credits are added for displacement, the adverse impact caused by the system expansion not only is reversed but transformed into a significant environmental benefit. The effect of the displacement more than compensates the emissions associated with the electricity generation requirements for the production of CO 2 , as much more electricity will be displaced. Results provide an understanding of the evolution of the system’s net carbon balance of all four field development strategies studied. This information can be useful to CO 2 -EOR operators seeking value in storing more CO 2 through a carbon credit program (e.g., the 45Q federal carbon credit program). Most importantly, this study serves as confirmation that CO 2 -EOR can be operationally designed to both enhance oil production and reduce greenhouse gas emissions to the atmosphere.

02 PETROLEUM↗
DOE OSTI2026

Current ramp-up studies for NSTX-U in support of the development of non-inductive current ramp-up scenarios in STs

The Spherical Tokamak (ST) is a low-aspect-ratio tokamak projected to enable simultaneous operation at high normalized toroidal beta and high bootstrap current fraction. However, a compact ST reactor cannot be built with a full-sized solenoid. The remaining current required for sustained operation must be ramped up non-inductively. Sustained 100% non-inductive current drive at the MA level has not yet been demonstrated on an ST. Non-inductive current ramp-up is therefore a more challenging objective that the NSTX-U research program aims to address. In support of this development, free-boundary TRANSP simulations have been used to develop a current ramp-up scenario in which a significant fraction of the current is driven non-inductively by a combination of neutral-beam and bootstrap current drive. The resulting discharge has properties favorable for non-inductive current drive, such as a low normalized internal plasma inductance of approximately 0.45, a minimum safety factor exceeding 2, and a slightly reversed-shear q-profile. In these discharges, the plasma current ramps to 900 kA within 250 ms in an L-mode configuration, with varying electron density and density profiles. These discharges should be suitable for next-step NSTX-U experiments aimed at generating a robust L-mode fiducial scenario with low central solenoid flux consumption, which could be progressively improved as new NSTX-U experimental discharges are developed.

Raman, Roger [Univ. of Washington, Seattle, WA (Un↗
DOE OSTI2015

Engineering management challenges of the CIGeO Project - 15576

After being involved for years in the conceptual studies on the French Deep Geological Repository's (DGR) design for ANDRA, INGeROP (www.ingerop.com) is carrying out since 2012 the global project management and the technical integration of the preliminary, basic and detailed design of the Cigeo project, within the framework of GAIYA consortium. The article presents some particular organizational aspects that turned out to be more challenging than foreseen in the course of our activities. Starting from the presentation of real examples, some lessons learned are derived as well as practices of interest in solving analogue issues in similar projects, with focus on their application to the engineering phase of geological repositories in different countries. Finally, the paper concludes with some avenues for reflection on the 'reversibility' - including 'retrievability' - requirement asked for by the French public and government and its consequences on the engineering choices, on the expected lifetime of components and structures and on the (increased) complexity of CIGeO systems. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Investigation of reactions in a fluidized bed reactor during chemical looping combustion of coal/steam with copper oxide-iron oxide-alumina oxygen carrier

This paper presents data on conversion of two different coals with a chemical looping oxygen carrier, CuO-Fe 2 O 3 -alumina, and over a range of conditions including steam and various levels of reduction of the oxygen carrier. Reactions of coal/steam/CuO-Fe 2 O 3 -alumina oxygen carrier and coal/steam/partially reduced CuO-Fe 2 O 3 -alumina oxygen carrier were investigated with Wyodak coal and Illinois #6 coal in a fluidized bed reactor. Temperature programmed reaction studies indicated that the oxygen carrier enhanced the steam gasification/combustion rates of both coals. Rates of gasification/combustion were higher with Wyodak coal (sub bituminous) than that with Illinois #6 coal (bituminous). In addition to the increase in reaction rates, the total moles of carbon that were gasified and combusted from coal/steam increased in the presence of the oxygen carrier. The reduced oxygen carrier promoted the water-gas shift reaction when reacted with synthesis gas in the presence of steam, but the reverse water gas shift reaction was observed when steam was not present. The partially reduced oxygen carrier enhanced the production of H 2 from coal/steam, which was different from the observations with un-reduced oxygen carrier. Water splitting reaction to produce H 2 was also observed with the reduced oxygen carrier. CuO-Fe 2 O 3 -alumina reacted with coal during the temperature ramp to 850 °C even in the absence of steam due to the chemical-looping oxygen uncoupling (CLOU) reaction. Here, the fourier transform infra-red (FTIR) analysis indicated the presence of volatile aromatics during the temperature ramp and these may have also contributed to the reactions with the oxygen carrier in the absence of steam. Increasing steam concentration had a negative effect on the CLOU reaction.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2024

Miniaturized Magnetoelastic Sensor System

This article describes the design, assembly, and implementation of a hand-held, magnetic-field-based sensor system that can be adapted for a variety of sensing applications. The miniaturized system is based on Chemical Identification by Magneto-Elastic Sensing (ChIMES) technology, which uses three concentric solenoid coils to wirelessly interrogate a sensor body comprised of a response material coupled to a magnetoelastic wire. The response material expands when it encounters a target, imposing mechanical stress on the wire and altering its magnetic permeability. The sensor bodies are passive, requiring no external power source, and they are small, measuring about 15 mm in length and 3.0 mm in diameter. Up to four sensor bodies can be configured as an evenly-spaced linear array. The sensor system operates by applying a low-frequency, current-stabilized, filtered triangle wave to a uniform-density excitation coil to switch the magnetic domains within the wire. Further, the responses from the sensors are picked up by a detection coil as stress-induced changes in the Faraday voltage, and the strong magnetic field induced by the excitation coil in the detection coil is nullified by a cancellation coil reverse-wound in series with the detection coil. The responses of the sensors in an array are separated in time by a linear gradient dc biasing coil. The sensors can be interrogated through metallic and nonmetallic barriers. The signals from the detection coil and the excitation coil are digitized by a pair of bipolar analog-to-digital converters (ADCs). A Raspberry Pi single-board computer (SBC) and associated software perform data acquisition and control all aspects of the sensor system hardware. The program allows the user to select the number of sensors in the array, the type of signal that is being collected, and the number of samples to take. The program also allows for signal processing of the sensor data, such as baseline correction. The program can differentiate sensor peaks from each other and calculate the magnitude of each sensor response with less than 1% error. The data are then displayed along with a graph of the signal.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2019

Automated Reconstruction of Control Logic for Programmable Logic Controller Forensics

This paper presents Similo, an automated scalable framework for control logic forensics in industrial control systems. Similo is designed to investigate denial of engineering operations (DEO) attacks, recently demonstrated to hide malicious control logic in a programmable logic controller (PLC) at field sites from an engineering software (at control center). The network traffic (if captured) contains substantial evidence to investigate DEO attacks including manipulation of control logic. Laddis, a state-of-the-art forensic approach for DEO attacks, is a binary-logic decompiler for the Allen-Bradley’s RSLogix engineering software and MicroLogix 1400 PLC. It is developed with extensive manual reverse engineering effort of the underlying proprietary network protocol and the binary control logic. Unfortunately, Laddis is not scalable and requires similar efforts to extend on other engineering software/PLCs. The proposed solution, Similo, is based on the observation that engineering software of different vendors are equipped with decompilers. Similo is a virtual-PLC framework that integrates the decompilers with their respective (previously-captured) ICS network traffic of control logic. It recovers the binary logic into a high-level source code (of the programming languages defined by IEC 61131-3 standard) automatically. Similo can work with both proprietary/open protocols without requiring protocol specifications and the binary formats of control logic. Thus, it is scalable to different ICS vendors. We evaluate Similo on three PLCs of two ICS vendors, i.e. MicroLogix 1400, MicroLogix 1100, and Modicon M221. These PLCs support proprietary protocols and the control logics written in two programming languages: Ladder Logic and Instruction List. The evaluation results show that Similo can accurately reconstruct a control logic from an ICS network traffic and can be used to investigate the DEO attacks effectively.

Ali qasim, Syed↗
DOE OSTI2024

De novo design of modular protein hydrogels with programmable intra- and extracellular viscoelasticity

Relating the macroscopic properties of protein-based materials to their underlying component microstructure is an outstanding challenge. Here, we exploit computational design to specify the size, flexibility, and valency of de novo protein building blocks, as well as the interaction dynamics between them, to investigate how molecular parameters govern the macroscopic viscoelasticity of the resultant protein hydrogels. We construct gel systems from pairs of symmetric protein homo-oligomers, each comprising 2, 5, 24, or 120 individual protein components, that are crosslinked either physically or covalently into idealized step-growth biopolymer networks. Through rheological assessment, we find that the covalent linkage of multifunctional precursors yields hydrogels whose viscoelasticity depends on the crosslink length between the constituent building blocks. In contrast, reversibly crosslinking the homo-oligomeric components with a computationally designed heterodimer results in viscoelastic biomaterials exhibiting fluid-like properties under rest and low shear, but solid-like behavior at higher frequencies. Exploiting the unique genetic encodability of these materials, we demonstrate the assembly of protein networks within living mammalian cells and show via fluorescence recovery after photobleaching (FRAP) that mechanical properties can be tuned intracellularly in a manner similar to formulations formed extracellularly. We anticipate that the ability to modularly construct and systematically program the viscoelastic properties of designer protein-based materials could have broad utility in biomedicine, with applications in tissue engineering, therapeutic delivery, and synthetic biology.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Field responsive mechanical metamaterials

Typically, mechanical metamaterial properties are programmed and set when the architecture is designed and constructed, and do not change in response to shifting environmental conditions or application requirements. Here, we present a new class of architected materials called field responsive mechanical metamaterials (FRMMs) that exhibit dynamic control and on-the-fly tunability enabled by careful design and selection of both material composition and architecture. To demonstrate the FRMM concept, we print complex structures composed of polymeric tubes infilled with magnetorheological fluid suspensions. Modulating remotely applied magnetic fields results in rapid, reversible, and sizable changes of the effective stiffness of our metamaterial motifs.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Dynamic modeling and simulation of pressure swing adsorption processes using toPSAil

Pressure swing adsorption (PSA) has attracted significant recent interest for chemical process intensification due to its potential for high energy efficiency and amenability to small, modular designs. However, the lack of simulation tools that are readily available, transparent, and trusted, has been identified as a serious impediment to widespread adoption of PSA, as well as to further research on PSA modeling, numerical solution, optimization, and control. This paper presents a complete framework for dynamic modeling and simulation of PSA processes and its implementation in an open-source simulator called toPSAil. Further, the presentation is tutorial and includes many modeling and implementation details often overlooked in existing literature. Novel methods are presented for handling flow reversals and implementing various pressure–flow relationships, along with controlled boundary conditions. Finally, the code contains several innovations designed to improve efficiency and reduce the extensive trial-and-error tuning often required to produce a working PSA cycle.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

TEAMER: Biofouling Analysis for Wave Energy Piston Design - Load Cell Data

Biofouling and corrosion are a major concern for all ocean-deployed components, especially when mechanical motion is involved. Triton has developed the concept of a biofouling mitigation seal as part of the piston sealing assembly for the Triton Wave Energy Converter (TSI-WEC). This mitigation seal has the purpose of preventing the formation of a biofilm on the inside of the piston cylinder. It is hypothesized that the prevention of a biofilm will reduce the amount of macro-biofouling that can occur in the piston assembly. The mitigation seal can also reduce the wear on the main dynamic seal, helping to maintain smooth operation and water-tightness. The cylinder is made from a thermoset composite epoxy, which is resistant to corrosion. However, no studies have researched the material's performance with biofouling. Triton placed two prototype Power Take-Off (PTO) assemblies in a PNNL biofouling tank, one with a biofouling mitigation seal and one without, allowing for an evaluation of seal effectiveness at the prevention of biofouling. In actual WEC operation, wave action would react against the piston, which would drive the linear actuator and electric generator, providing electrical power. In the test setup, this was reversed; a linear actuator was powered to drive the piston in a consistent motion within the cylinder. There are two assemblies: one has a biofouling mitigation seal, the other (control) does not. The following data encompasses a 4 month test period, with load cells being used to monitor piston friction force. Results from this testing will be used to improve seal design and material selection, mitigating risk of premature failure during open water testing and evaluation. This project is part of the TEAMER RFTS 3 (request for technical support) program.

16 TIDAL AND WAVE POWER↗
DOE OSTI2015

Center for Electrocatalysis, Transport Phenomena, and Materials (CETM) for Innovative Energy Storage - Final Report

EFRC vision. The direct use of organic hydrides in fuel cells as virtual hydrogen carriers that generate stable organic molecules, protons, and electrons upon electro-oxidation and can be electrochemically charged by re-hydrogenating the oxidized carrier was the major focus of the Center for Electrocatalysis, Transport Phenomena and Materials for Innovative Energy Storage (EFRC-ETM). Compared to a hydrogen-on-demand design that includes thermal decomposition of organic hydrides in a catalytic reactor, the proposed approach is much simpler and does not require additional dehydrogenation catalysts or heat exchangers. Further, this approach utilizes the advantages of a flow battery (i.e., separation of power and energy, ease of transport and storage of liquid fuels) with fuels that have system energy densities similar to current hydrogen PEM fuel cells. EFRC challenges. Two major EFRC challenges were electrocatalysis and transport phenomena. The electrocatalysis challenge addresses fundamental processes which occur at a single molecular catalyst (microscopic level) and involve electron and proton transfer between the hydrogen rich and hydrogen depleted forms of organic liquid fuel and the catalyst. To form stable, non-radical dehydrogenation products from the organic liquid fuel, it is necessary to ensure fast transport of at least two electrons and two protons (per double bond formation). The same is true for the reverse hydrogenation reaction. The transport phenomena challenge addresses transport of electrons to/from the electrocatalyst and the current collector as well as protons across the polymer membrane. Additionally it addresses prevention of organic liquid fuel, water and oxygen transport through the PEM. In this challenge, the transport of protons or molecules involves multiple sites or a continuum (macroscopic level) and water serves as a proton conducting medium for the majority of known sulfonic acid based PEMs. Proton transfer in the presence of prospective organic liquid fuels was studied. During EFRC program various types of electrocatalysts, classes of fuels, and membranes have been investigated.

25 ENERGY STORAGE↗