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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 1,531 records · Page 85
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Neutrino Program at Fermilab - Enhancing Proton Beam Power and Accelerator Infrastructure

The upcoming long baseline neutrino experiments aim to enhance proton beam power to multi-MW scale and utilize large-scale detectors to address the challenge of limited event statistics. The DUNE experiment at LBNF will test the three neutrino flavor paradigm and directly search for CP violation by studying oscillation signatures in the high intensity $\nu_{\mu}$ (anti-$\nu_{\mu}$) beam to $\nu_e$ (anti-$\nu_e$) measured over a long baseline.\par Higher beam power and improved accelerator up-time will enhance neutrino flux for the neutrino program by increasing the number of protons on target. LBNF/DUNE, as well as PIP-II upgrade and Accelerator Complex Evolution (ACE) plan, play a vital role in this effort. The scientific potential of ACE plan extends beyond neutrino physics, encompassing endeavors such as the Muon Collider, Charged Lepton Flavor Violation (CLFV), Dark Sectors, and exploration of neutrinos beyond DUNE. In the era of higher-power accelerator operation, research in target materials and beam instrumentation is crucial for optimizing design modifications. This abstract discusses Fermilab ACE, the science opportunities it provides, and how Fermilab is pushing the limits of proton beam power and accelerator infrastructure. By tackling neutrino beam challenges and exploring research and development ideas, we are advancing our understanding of fundamental particles and their interactions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2022

Warm Unit Stand Analysis for Proton Improvement Project II

The Proton Improvement Project II, commonly referred to as PIP II, is a linear accelerator overhaul at Fermilab to eventually double the output of its existing proton beam to continue to be the leading force in high energy physics. The proton beam is created through a series of high frequency cryomodules that must be connected utilizing a combination of magnets and vacuum pumps to ensure the beam is properly aligned. A housing mechanism for the magnets and vacuum pumps (Warm Units) will be placed between the cryomodules for realignment and require multiple stages of 6 degree-of-freedom adjustment options, to ensure that the beam alignment can fit all realistic requirements. Extensive testing and design modifications on the Warm Unit stand was completed to confirm not only the strength of the unit in nominal configuration, but also at each possible adjustment orientation for each 6 degree-of-freedom option. Structural analysis was also completed for various unique loading conditions i ncluding transportation loading and confirming the unit satisfies international building code. Simultaneously, testing and design modifications were done to confirm that the frequency modes of the system resided outside of concern ranges, which is determined by Fermilab safety codes and is set to exceed 15 Hz. Design changes that simultaneously stiffen the system to raise the lowest frequency modes while expanding access for technicians and allow for easier fabrication were developed and implemented into the Warm Unit stand. Various relationships between the design changes and the overall vibrational patterns were also developed for future use and study as the rest of PIP II matures.

43 PARTICLE ACCELERATORS↗
DOE OSTI2024

Warm Unit Stand Assembly and Testing for Proton Improvement Plan - II

The Proton Improvement Project II (PIP II), situated at Fermilab, signifies a critical advancement in the realm of high-energy physics. PIP II, a linear accelerator renovation endeavor, aspires to double the output of the existing proton beam, reinforcing Fermilab’ s position as a vanguard in this field. The proton beam's creation involves a series of high-frequency cryomodules, necessitating environmental temperature arrays of magnets and vacuum pumps henceforth described as ‘Warm Units.’ The Warm Units include design features of : 1. insertion between the cryomodules, 2. multi-stage adjustments in six degrees of freedom to ensure precise beam alignment; 3. Natural frequency modes that avoid specified ranges. In adherence to Fermilab’ s stringent safety standards, comprehensive testing procedures are slated to validate the Warm Units' capacity to simultaneously achieve local alignment adjustments while averting low-frequency oscillation less than 15 Hertz. The testing regimen will scrutinize the Warm Units' alignment adjustment capabilities and their resilience against low-frequency oscillations, with an overarching objective of satisfying the Final Design Review criteria specific to the PIP II initiative. This project works to furnish technicians responsible for the assembly of Warm Units with a comprehensive guide for successful installation, concurrently documenting any requisite design modifications essential for achieving a real-world configuration.

43 PARTICLE ACCELERATORS↗
DOE OSTI2024

Neutrino Program at Fermilab -- Enhancing proton beam power and accelerator infrastructure

The upcoming long baseline neutrino experiments aim to enhance proton beam power to multi-MW scale and utilize large-scale detectors to address the challenge of limited event statistics. The DUNE experiment at LBNF will test the three neutrino flavor paradigm and directly search for CP violation by studying oscillation signatures in the high intensity $\nu_{\mu}$ (anti-$\nu_{\mu}$) beam to $\nu_{e}$ (anti-$\nu_{e}$) measured over a long baseline. Higher beam power and improved accelerator up-time will enhance neutrino flux for the neutrino program by increasing the number of protons on target. LBNF/DUNE, as well as PIP-II upgrade and Accelerator Complex Evolution (ACE) plan, play a vital role in this effort. The scientific potential of ACE plan extends beyond neutrino physics, encompassing endeavors such as the Muon Collider, Charged Lepton Flavor Violation (CLFV), Dark Sectors, and exploration of neutrinos beyond DUNE.\par In the era of higher-power accelerator operation , research in target materials and beam instrumentation is crucial for optimizing design modifications. This abstract discusses Fermilab ACE, the science opportunities it provides, and how Fermilab is pushing the limits of proton beam power and accelerator infrastructure. By tackling neutrino beam challenges and exploring research and development ideas, we are advancing our understanding of fundamental particles and their interactions.

43 PARTICLE ACCELERATORS↗
DOE OSTI2024

Studies of e+e- Pair Photo-Production on Proton Target at 8 GeV in the GlueX Experiment

Lepton pair production has played an important role in both nuclear and particle physics, being among the earliest calculations utilizing QED, and seen most famously in the discovery of the J= at BNL. A technique is presented for measuring the linear polarization of GeV scale photon beams through the detection of e+e? pairs photo-produced in the target. This technique is applied to the analysis of GlueX data on proton target. Simulation predicts the analyzing power for pair production to be :5725 ? 0:0025 for the GlueX data, and the analysis of experimental data gives a linear polarization of approximately 35%, in good agreement with other measurements of beam polarization. The pair production technique is complementary to other electromagnetic and hadronic measurements of beam polarization, and is generally applicable in experiments that allow for forward angle electron and positron identi?fication and tracking. To facilitate this study, a neural net was trained for e=? separation to eliminate the pion background. Further, it is demonstrated that these e+e? pairs are sensitive to the proton charge form factor, which opens up the possibility for a new method to measure the proton RMS charge radius.

Schick, Andrew↗
DOE OSTI2024

Proton-exchange membrane

A proton-exchange membrane includes a polymer matrix, polymer fibers, or a combination thereof. The proton-exchange membrane also includes a proton-conducting material distributed on the polymer matrix, on the polymer fibers, in the polymer fibers, or a combination thereof.

Aulich, Ted R.↗
DOE OSTI2020

Chapter Twelve - Proton transfer and drug binding details revealed in neutron diffraction studies of wild-type and drug resistant HIV-1 protease

HIV-1 protease is an essential therapeutic target for the design and development of antiviral inhibitors to treat AIDS. We used room temperature neutron crystallography to accurately determine hydrogen atom positions in several protease complexes with clinical drugs, amprenavir and darunavir. Hydrogen bonding interactions were carefully mapped to provide an unprecedented picture of drug binding to the protease target. We demonstrate that hydrogen atom positions within the enzyme catalytic site can be altered by introducing drug resistant mutations and by protonating surface residues that trigger proton transfer reactions between the catalytic Asp residues and the hydroxyl group of darunavir. When protein perdeuteration is not feasible, we validate the use of initial H/D exchange with unfolded protein and partial deuteration in pure D2O with hydrogenous glycerol to maximize deuterium incorporation into the protein, with no detrimental effects on the growth of quality crystals suitable for neutron diffraction experiments.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2020

Protein kinase A in the neutron beam: Insights for catalysis from directly observing protons

Protein kinases transmit chemical signals by phosphorylating substrate proteins, thus regulating a multitude of cellular processes. cAMP-dependent protein kinase (PKA), a prototypical enzyme for the whole kinase family, has been the focus of research for several decades, however, the details of the chemical mechanism of phosphoryl group transfer have remained unknown. We used neutron crystallography to map key proton sites and hydrogen bonding interactions in the PKA catalytic subunit (PKAc) in a product complex containing adenosine diphosphate (ADP) and the phosphorylated high affinity protein kinase substrate (pPKS) peptide. To improve neutron diffraction, we deuterated PKAc allowing us to use very small crystals. In the product complex, the phosphoryl group of pPKS is protonated whereas the catalytic Asp166 is not. H/D exchange analysis of the main-chain amides and comparison with the NMR analysis of PKAc with inhibitor peptide complex revealed exchangeable amides that may distinguish the catalytic and inhibited states.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Electron and proton conductivity of Fe-N-C cathodes for PEM fuel cells: A model-based electrochemical impedance spectroscopy measurement

Impedance spectra of a PEM fuel cell with three Fe-N-C cathodes have been measured under the H 2 /N 2 testing regime. The spectra have been fitted using a recently developed physics-based impedance model, which takes into account finite proton ($σ_p$) and electron ($σ_e$) conductivity of the oxygen-free cathode catalyst layer. Fitting allowed to extract numerical data for $σ_p$, $σ_e$, the double layer capacitance, and the inductance of cables used for measuring impedance spectra. The values of σp and σe are close to what previously found for standard Pt/C electrodes, which is found for the first time using PGM-free catalysts. The method enables simultaneous measurement of reference proton and electron conductivity of PEMFC cathode.

25 ENERGY STORAGE↗
DOE OSTI2021

High performance protonic ceramic fuel cell systems for distributed power generation

The technology landscape around distributed generation continues to evolve in response to increasing demand for high-efficiency, low-emission, low-cost power generation. While emerging distributed power technologies, such as solid oxide fuel cells (SOFCs), continue to advance, they still face challenges due to their high capital costs, and shorter lifetimes that typically arise from electrochemical stack performance degradation at high operating temperatures (>750 °C). Recent advancements in protonic ceramic fuel cells (PCFCs) offer the potential to mitigate drawbacks of their higher temperature SOFC counterparts by enabling lower operating temperatures (550 °C–600 °C) with acceptable power densities. Here the present work leverages the recent progress in protonic ceramic cell and stack technology development to generate viable system configurations and evaluate the energetic performance potential of PCFC-based systems for stationary power generation. Process system engineering of two water-neutral system concepts, which provide 25 kW of electric power and process hot water, are presented and evaluated through sensitivity studies. Stack design parameters are altered and used to gauge the effect on system performance characteristics, including fuel cell stack and balance-of-plant sizing requirements, and electric and cogeneration efficiencies. The study finds that the potentially high per-pass fuel utilization capability of PCFC stacks could enable unprecedented electric efficiencies approaching 70% without hybridization with other prime movers.

25 ENERGY STORAGE↗
DOE OSTI2025

Proton spin from small-x with constraints from the valence quark model

We apply the valence quark model [1] to constrain the non-perturbative initial condition for the small-x helicity evolution. The remaining free parameters are constrained by performing a global analysis akin to [2] to the available polarized small-x deep inelastic scattering data. A good description of the world data is obtained with only 8 free parameters. The model parameters are tightly constrained by the data, allowing us to predict the proton polarized structure function $g^p_1$ to be negative at small x. Furthermore, we obtain the small-x quark and gluon spins to give a contribution $\int^{0.1}_{10^{-5}} dx (\frac{1}{2}\Delta\Sigma + \Delta{G}) = 0.63 ± 0.10$ or $1.35 ± 0.16$ (or to the proton spin, depending on the applied running coupling prescription.

Color-class condensate↗
DOE OSTI2021

Current Status on the Manufacturing of Nanomaterials for Proton Exchange Membrane Energy Systems by Vapor-Based Processes

Development of novel technologies for catalyst synthesis and membrane electrode assembly (MEA) fabrication is of primary importance for further improvement of the performance and economics of proton exchange membrane fuel cells (PEMFCs) and proton exchange membrane water electrolyzers (PEMWEs). While the traditional manufacturing methods are time-consuming, energy intensive, and require many processing steps, the new vapor-based methods provide many benefits including the development of improved catalysts and catalyst supports, deposition of uniform thin films, reduction of catalyst loading, and minimizing the number of manufacturing steps. Recent publications in the field identified spray pyrolysis, reactive spray deposition technology, chemical vapor deposition, and atomic layer deposition as advanced vapor-based catalyst synthesis and deposition methods used for fabrication of MEAs for PEMFCs and PEMWEs. Here, the MEAs fabricated via vapor-based processes have shown significant performance improvements in comparison to the state-of-the-art MEAs, which are attributed to better catalyst distribution, improved catalyst supports, and controlled, uniform catalyst layer microstructures. This review provides an overview of the vapor-based synthesis and deposition methods currently being used for the development of PEM-based devices. The advantages and disadvantages of these methods are critically compared and discussed while the outlook for future development is provided.

25 ENERGY STORAGE↗
DOE OSTI2023

Tomography of pions and protons via transverse momentum dependent distributions

We perform the first simultaneous extraction of parton collinear and transverse degrees of freedom from low-energy fixed-target Drell-Yan data in order to compare the transverse momentum dependent (TMD) parton distribution functions (PDFs) of the pion and proton. We demonstrate that the transverse separation of the quark field encoded in TMDs of the pion is more than 4⁢𝜎 smaller than that of the proton. Additionally, we find the transverse separation of the quark field decreases as its longitudinal momentum fraction decreases. In studying the nuclear modification of TMDs, we find clear evidence for a transverse EMC effect. We comment on possible explanations for these intriguing behaviors, which call for a deeper examination of tomography in a variety of strongly interacting quark-gluon systems.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS2020

Medical Proton Test Facilities (MPTFs) Lessons Learned on the Unique Aspects for Single Event Effects (SEE) Testing of Electronics in the 200 MeV Regime

Ever since the closure of the Indiana University Cyclotron Facility (IUCF) in 2014, there has been an increasing use of medical proton therapy facilities (MPTF) for SEE testing with protons in the 200 MeV or greater regime. This talk covers some of the unique features and considerations for utilizing MPTFs including both logistical and technical aspects. This presentation provides an overview of lessons learned for SEE testing at MPTFs.

Medical Proton Test Facilities (MPTFs)↗
DOE OSTI2023

Unlocking High Capacity and Fast Na + Diffusion of H x CrS 2 by Proton-Exchange Pretreatment

This study presents a new material, “H x CrS 2 " (denotes approximate composition) formed by proton-exchange of NaCrS 2 which has a measured capacity of 728 mAh g -1 with significant improvements to capacity retention, sustaining over 700 mAh g -1 during cycling experiments. This is the highest reported capacity for a transition metal sulfide electrode and outperforms the most promising proposed sodium anodes to date. H x CrS 2 exhibits a biphasic structure featuring alternating crystalline and amorphous lamella on the scale of a few nanometers. This unique structural motif enables reversible access to Cr redox in the material resulting in higher capacities than seen in the parent structure which features only S redox. In conclusion, pretreatment by proton-exchange offers a route to materials such as H x CrS 2 which provide fast diffusion and high capacities for sodium-ion batteries.

25 ENERGY STORAGE↗
DOE OSTI2023

Rational Materials and Structure Design for Improving the Performance and Durability of High Temperature Proton Exchange Membranes (HT-PEMs)

Hydrogen energy as the next-generation clean energy carrier has attracted the attention of both academic and industrial fields. A key limit in the current stage is the operation temperature of hydrogen fuel cells, which lies in the slow development of high-temperature and high-efficiency proton exchange membranes. Currently, much research effort has been devoted to this field, and very innovative material systems have been developed. The authors think it is the right time to make a short summary of the high-temperature proton exchange membranes (HT-PEMs), the fundamentals, and developments, which can help the researchers to clearly and efficiently gain the key information. In this paper, the development of key materials and optimization strategies, the degradation mechanism and possible solutions, and the most common morphology characterization techniques as well as correlations between morphology and overall properties have been systematically summarized.

08 HYDROGEN↗