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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 73 records · Page 4

Upgrade of the Materials Analysis Particle Probe (MAPP-U) to decipher the impact of lithium-based surfaces on NSTX-U plasma behavior

Understanding the plasma wall interaction (PWI) remains a critical issue for the feasibility of thermonuclear magnetic fusion energy solutions. Key issues with PWI mechanisms in fusion tokamak reactors include: evolution of surface chemistry and its role on hydrogen retention. In particular how low-Z coatings such as lithium can impact the behavior of plasma at the edge and in the core. PMI (plasma-material interactions) are particularly important for strategies that involve low-recycling regimes and the use of lithium PFS (plasma-facing surfaces) to attain them, as in the case of NSTX-U. Recent reports have indicated the importance of access to the evolving plasma-facing surface during and in-between plasma discharges. Changes in surface chemistry and morphology due to ion bombardment and the difficulty of diagnosing plasma-facing surfaces, especially reactive surfaces, complicate the development of a predictive understanding of the wall and its interaction with the plasma. Consequently, this impairs the ability to design advanced PFC materials for future plasma-burning fusion reactors and appropriate PMI code validation. The Materials Analysis Particle Probe (MAPP) is an established and on-going PMI probe diagnostic system compatible with the highly chemically reactive system of lithium and boron coatings adopted by the NSTX-U research program. MAPP is the first PMI diagnostic to capture the surface physics and chemistry in-vacuo in a fusion tokamak system and correlate this data to controlled plasma shots. Currently MAPP captures this information at a fixed radial location at the NSTX-U outboard divertor region. The MAPP diagnostic has enabled understanding of the near-surface and surface chemistry of complex evolving lithiated and borated carbon-based PFC surfaces retention and transport of hydrogen. Coupled to atomistic simulations in collaboration with P. Krstic of Stony Brook U. MAPP has been very successful in achieving high-impact scientific research in its current grant period evidenced by two invited review articles and over 20 peer-reviewed manuscripts and over 40 contributed and invited presentations at both national and international conferences.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Linear Theory of Electromagnetic Ion Beam Instabilities in the Earth’s Forshock: Peter Gary’s Contributions (1981–1991)

We discuss Peter Gary’s contributions to the understanding of the origin and properties of ultra-low frequency (ULF) waves in the Earth’s foreshock during the period when the International Sun Earth Explorer spacecraft (ISEE-1 and -2) provided unique data about the plasma and wave environment in this region. Peter’s work concerning the linear theory of electromagnetic ion beam instabilities is contained in five journal articles and then summarized in a review article, all of which are discussed here. Brief summaries of observations and theory prior to ISEE as well as to later work are also included.

79 ASTRONOMY AND ASTROPHYSICS↗

IUE observations of cataclysmic variable

Twenty two approved International Ultraviolet Explorer (IUE) programs were studied over a 14 year period. These programs are listed. The observations and subsequent analysis centered on cataclysmic variables (close binaries with a late main sequence star transferring material to a primary white dwarf via an accretion disk). The early studies highlighted the flux distribution of the accretion disk at outburst and quiescence, while later studies accomplished time-resolved observations throughout the orbital cycles, the study of the outflowing winds present at outburst, the study of the white dwarf in those systems with low accretion rate. There are 39 publications resulting from this work which are listed. These results include those for individual systems (Stepanian's star, Lanning 10, AM Her, MV Lyr, TV Col, VW Hyi, T Leo, IR Gem, TT Ari, Z Cam, BV Pup, IP Peg, PG1030+590, V1315 Aql, SW UMa, V426 Oph, WZ Sge, BY Cam, and U Gem) as well as review articles in journals and publications from reviews at meetings that summarize the impact of IUE on the study of accretion disks, white dwarfs, and hot spots resulting from stream impact as well as magnetic accretion columns.

Szkody, Paula↗

Linear Theory of Electromagnetic Ion Beam Instabilities in the Earth’s Forshock: Peter Gary’s Contributions (1981-1991)

We discuss Peter Gary’s contributions to the understanding of the origin and properties of ultra-low frequency (ULF) waves in the Earth’s foreshock during the period when the International Sun Earth Explorer spacecraft (ISEE-1 and -2) provided unique data about the plasma and wave environment in this region. Peter’s work concerning the linear theory of electromagnetic ion beam instabilities is contained in five journal articles and then summarized in a review article, all of which are discussed here. Brief summaries of observations and theory prior to ISEE as well as to later work are also included.

Dan Winske↗

Expanding the Boundaries of Transuranium Chemistry

During the last several Heavy Elements Chemistry grant cycles under award(s): DE-FG02-13ER16414, we have published nearly 90 research articles (see bibliography) in 25 peer-reviewed journals. Additionally, this funding has resulted in several review articles. Together, these publications have already reached well over 4500 citations. These research articles have introduced several hundreds of new crystallographically authenticated f-element compounds and materials and have greatly affected the field of Heavy Elements Chemistry. Concentrating on the heaviest elements that can be studied on the milligram scale, the transplutonium elements are the focus of nearly 30 of these manuscripts containing results such as the first single crystal structure of a berkelium compound and californium presenting itself as an additional transition point in the actinide series.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗

Remote Science at Sea With Remotely Operated Vehicles

Conducting sea-going ocean science no longer needs to be limited to the number of berths on a ship given that telecommunications, computing, and networking technologies onboard ships have become familiar mechanisms for expanding scientists’ reach from onshore. The oceanographic community routinely works with remotely operated vehicles (ROVs) and pilots to access real-time video and data from the deep sea, while onboard a ship. The extension of using an ROV and its host vessel’s live-streaming capabilities has been popularized for almost 3 decades as a telepresence technology. Telepresence-enabled vessels with ROVs have been employed for science, education, and outreach, giving a greater number of communities viewing access to ocean science. However, the slower development of technologies and social processes enabling sustained real-time involvement between scientists on-ship and onshore undermines the potential for broader access, which limits the possibility of increasing inclusivity and discoveries through a diversity of knowledge and capabilities. This article reviews ocean scientists’ use of telepresence for ROV-based deep-sea research and funded studies of telepresence capabilities. The authors summarize these studies findings and conditions that lead to defining the use of telepresence-enabled vessels for “remote science at sea.” Authors define remote science at sea as a type of ocean expedition, an additional capability, not a replacement for all practices by which scientists conduct ocean research. Remote science for ocean research is an expedition at-sea directed by a distributed science team working together from at least two locations (on-ship and onshore) to complete their science objectives for which primary data is acquired by robotic technologies, with connectivity supported by a high-bandwidth satellite and the telepresence-enabled ship’s technologies to support the science team actively engaged before, during, and after dives across worksites. The growth of productive ocean expeditions with remote science is met with social, technical, and logistical challenges that impede the ability of remote scientists to succeed. In this article, authors review telepresence-enabled ocean science, define and situate the adjoined model of remote science at sea, and some infrastructural, technological and social considerations for conducting and further developing remote science at sea.

marine technology↗

A review on snake robot testbeds in granular and restricted maneuverability spaces

Here this article reviews the state of the art in evaluating snake robots for small spaces such as a collapsed building where the snake is either locomoting in restricted maneuverability spaces, such as narrow pipes or tunnels, or pushing through granular regions, such as dirt and rubble. It makes recommendations on designing a testbed that can enable a comprehensive evaluation of a snake robot’s overall capability and an objective comparison of different snakes. A survey of 31 papers reveals that 20 testbeds were used to test snake robots in restricted maneuverability environments. All of those were built specifically to test a particular snake robot rather than for comparison with other snake robots, but each offers insights into designing comprehensive, comparative testbeds. The article analyzed these 20 testbeds in terms of how well they addressed the previously established disaster robotics metrics of scale (a dimensionless number) and four traversability elements, i.e. verticality, tortuosity, accessibility elements, and surface properties. This review suggests that two kinds of general testbeds are in need for the snake robot community: (1) a testbed with high physical fidelity for measuring suitability for a target application, and (2) a testbed which provides a dimensionless comparison of different snake robots. The review is expected to benefit the community in several ways. It can help form a consensus on a suite of metrics and test methods to incorporate into a testbed for evaluating and comparing different types of snake robots and capturing the performance of snake robots in more realistic work envelopes. The metrics and test methods can also pro-actively inform snake robot design as they offer more formally quantified work envelopes, thus accelerating technology transfer. The use of scale and traversability is expected to be applicable to robots in general.

42 ENGINEERING↗

Review of Ion Exchange Technologies for Cesium Removal from Caustic Tank Waste

This article reviews the historical uses of and current research into ion exchange for the removal of cesium (Cs) from defense-related nuclear waste streams. Emphasis is placed on key attributes of the two current leading ion exchangers for Cs removal: spherical resorcinol-formaldehyde, an elutable organic resin, and crystalline silicotitanate, a non-elutable crystalline solid. An understanding of the successes, issues, and limitations of past ion exchange experience may be helpful in better understanding current ion exchanger use. Emphasis is placed on Cs capacity, exchange kinetics, stability, and column hydrodynamics for processing alkaline wastes as well as the final waste forms of the ion exchangers.

Fiskum, Sandra K.↗

A retrospective review of von Neumann’s analysis of hidden variables in quantum mechanics

This article reviews the history of J. von Neumann’s analysis of hidden variables in quantum mechanics and the subsequent analysis by others. In his book The Mathematical Foundations of Quantum Mechanics , published in 1932, von Neumann performed an analysis of the consequences of introducing hidden parameters (hidden variables) into quantum mechanics. He arrived at two principal conclusions: first, hidden variables cannot be incorporated into the existing theory of quantum mechanics without major modifications, and second, if they did exist, the theory would have already failed in situations where it has been successfully applied. This analysis has been taken as an “incorrect proof” against the existence of hidden variables, possibly due to a mistranslation of the German word prufen . von Neumann’s so-called proof isn’t even wrong as such a proof does not exist, but it is an examination of the limitations imposed by internal consistency of the Hilbert space formulation of the theory. One of the earliest attempts to eliminate uncertainty, by D. Bohm, requires a major modification of quantum mechanics (observables are not represented by Hermitian operators), which supports von Neumann’s first principal conclusion. However, testing the Bohm theory requires constructing a physically impossible initial state. As such, the theory has no experimental consequences, so W. Pauli referred to it as an “uncashable check”. As there are no observable consequences, the Bohm theory is possibly a counterexample to von Neumann’s second conclusion that hidden variables in particular would have already led to a failure of the theory.

density matrix↗

Applications of nuclear physics

Today the applications of nuclear physics span a very broad range of topics and fields. This review discusses a number of aspects of these applications, including selected topics and concepts in nuclear reactor physics, nuclear fusion, nuclear non-proliferation, nuclear-geophysics, and nuclear medicine. The review begins with a historic summary of the early years in applied nuclear physics, with an emphasis on the huge developments that took place around the time of World War II, and that underlie the physics involved in designs of nuclear explosions, controlled nuclear energy, and nuclear fusion. The review then moves to focus on modern applications of these concepts, including the basic concepts and diagnostics developed for the forensics of nuclear explosions, the nuclear diagnostics at the National Ignition Facility, nuclear reactor safeguards, and the detection of nuclear material production and trafficking. The review also summarizes recent developments in nuclear geophysics and nuclear medicine. The nuclear geophysics areas discussed include geo-chronology, nuclear logging for industry, the Oklo reactor, and geo-neutrinos. The section on nuclear medicine summarizes the critical advances in nuclear imaging, including PET and SPECT imaging, targeted radionuclide therapy, and the nuclear physics of medical isotope production. Lastly, each subfield discussed requires a review article unto itself, which is not the intention of the current review; rather, the current review is intended for readers who wish to get a broad understanding of applied nuclear physics.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Emerging Trends in Emergent Stroke Neuroimaging

Purpose of Review: Various imaging techniques used in stroke evaluation have complementary, evolving roles. This article reviews recent updates in emergent stroke neuroimaging. Recent Findings: Multiple recent randomized trials showing benefit of endovascular therapy in strokes with confirmed large-vessel occlusion emphasize need for vessel imaging, typically CTA, in addition to unenhanced head CT. In addition, because recent trials published in 2018 showed efficacy of mechanical thrombectomy at up to 24 h from symptom onset in stroke patients with favorable ischemic core and/or penumbra assessments, imaging techniques to define viable and infarcted tissue, such as DWI or CT/MR perfusion imaging, have an increasing role in emergent stroke assessment. Other studies contributing to new AHA/ASA stroke guidelines are also discussed. Summary: Neuroimaging remains crucial to emergent stroke evaluation, with CTA, MRI, and perfusion studies playing an increasing role in identifying patients likely to benefit from treatment.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Bioinspired design toward nanocellulose-based materials

Nature provides lots of inspiration for material and structural design for various applications. Deriving design principles from the investigation of nature can provide a rich source of inspiration for the development of multifunctional materials. The bioinspired design templates mainly include mussels, nacre, and various plant species. As a sustainable and renewable feedstock, nanocellulose can be used to fabricate advanced materials with multifunctional properties through bioinspired designs. However, challenges and opportunities remain for realizing the full potential in the design of novel materials. Here, this article reviewed recent development in the bioinspired nanocellulose based materials and their application. This article summarizes the functions (e.g., surface wetting) and applications (e.g., composite) of bioinspired nanocellulose-based materials. The bioinspired design templates are discussed along with strategies, advantages, and challenges to the development of synthetic mimics. Additionally, mechanisms and processes (e.g., chemical modification, self-assembly) leading to biomimetic design are discussed. Finally, future research directions and opportunities of bioinspired nanocellulose-based materials are highlighted.

36 MATERIALS SCIENCE↗

Manipulating and Probing Ultrafast Atomic and Molecular Dynamics (Final Report)

This program has focused on the exploration and control of dynamics in atoms, small molecules, clusters, and micro- or nano-structures following ultrafast excitation and/or driven by strong oscillating fields. In our principal experiments, gas phase atoms and molecules were exposed to short pulses of electromagnetic radiation with frequencies ranging from THz into the XUV spectral regions, and with durations from picoseconds to attoseconds. The pulses coherently induce and/or probe dynamics in the electronic, vibrational, and rotational degrees of freedom of the targets. The overarching goal of the various projects has been to exploit strong-field processes and/or implement novel ultrafast techniques for manipulating and probing coherent electronic and nuclear motion. Typically, the relevant system evolution occurs over attosecond to picosecond timescales. In doing so, we have gained a more complete picture of correlated multi-particle dynamics in atoms, molecules, and other complex systems and expanded the toolbox of useful techniques for manipulating and probing those dynamics. Grant funds were primarily used to: (i) pay salaries and fringe benefits for the PI and postdocs and stipends, tuition, and health care costs for graduate students; (ii) cover travel expenses for the PI, postdocs, and students to attend and participate in professional meetings, conferences, and workshops; and (iii) purchase research materials, supplies, and equipment required for experiments. The research resulted in the publication of 24 peer reviewed articles (including 1 in Nature Physics, 2 in Nature Communications, 7 in Physical Review Letters, and 12 in Physical Review A), and 4 PhD dissertations. The specific results from different funding periods are summarized separately in the main report.

74 ATOMIC AND MOLECULAR PHYSICS↗

The Human Phenotype Ontology in 2017

Deep phenotyping has been defined as the precise and comprehensive analysis of phenotypic abnormalities in which the individual components of the phenotype are observed and described. The three components of the Human PhenotypeOntology (HPO; www.human-phenotype-ontology.org) project are the phenotype vocabulary, disease-phenotype annotations and the algorithms that operate on these. These components are being used for computational deep phenotyping and precision medicine as well as integration of clinical data into translational research. The HPO is being increasingly adopted as a standard for phenotypic abnormalities by diverse groups such as international rare disease organizations, registries, clinical labs, biomedical resources, and clinical software tools and will thereby contribute toward nascent efforts at global data exchange for identifying disease etiologies. This update article reviews the progress of the HPO project since the debut Nucleic Acids Research database article in 2014, including specific areas of expansion such as common (complex) disease, new algorithms for phenotype driven genomic discovery and diagnostics, integration of cross-species mapping efforts with the Mammalian Phenotype Ontology, an improved quality control pipeline, and the addition of patient-friendly terminology.

59 BASIC BIOLOGICAL SCIENCES↗

Impact of COVID-19 on materials science research innovation and related pandemic response

The scope of impact that the coronavirus SARS-CoV-2 has had and continues to have on life, society, and the world as we know it will be debated for years to come. One thing is for certain, scientists, engineers, clinicians, and researchers around the globe rallied to heed the call for innovation, particularly in the field of materials science. Here, we feature six articles, two of which showcase primary consumable materials research and development, along with four review articles highlighting materials innovation over the last 18 months in diagnostics, prevention, and treatment of SARS-CoV-2 infection.

36 MATERIALS SCIENCE↗

Non-Coalescence in Microgravity: Science and Technology

Non-coalescence of two bodies of the same liquid and the suppression of contact between liquid drops and solid surfaces (nonwetting) has been studied through a pair of parallel investigations being conducted at the Georgia Institute of Technology and the Microgravity Research and Support (MARS) Center in Naples, Italy. Both non- coalescence and nonwetting may achieved by either: i) exploiting the mechanism of thermocapillary convection to drive a lubricating film of surrounding gas (air) into the space between the two liquid free surfaces (non-coalescence) or between the drop free surface and the solid (nonwetting); or ii) using the otherwise forced motion of the solid (or one liquid) surface to generate the lubricating film. These, and other types of related phenomena are discussed in our recent review article (Neitzel GP, Dell'Aversana P. 2002. Noncoalescence and nonwetting behavior of liquids. Annual Review of Fluid Mechanics 34: 267-89). This project was a continuation of earlier research on this subject and includes the possible uses of non-coalescing/wetting systems in technological applications.

Neitzel, G. Paul↗

The Differential Equations That Model Diseases

In this brief tutorial, I will describe the simplest way of modeling a deadly infectious disease, such as COVID-19. I will show that at early times, the disease grows exponentially, but at late times, falls off like a Bell curve. I will solve the equations numerically with Python. A common mathematical model is the so-called compartmental model, where diseases can move people between "categories" such as healthy, infectious, or truly sick. This is a large, well established field and there are many good resources on this topic. I started with the SIAM review article The mathematics of infectious diseases. However, there are many excellent textbooks and more modern reviews as well.

60 APPLIED LIFE SCIENCES↗

Additive Manufacturing of Metallic Materials: A Review

In this review article, the latest developments of the four most common additive manufacturing methods for metallic materials are reviewed, including powder bed fusion, direct energy deposition, binder jetting, and sheet lamination. In addition to the process principles, the microstructures and mechanical properties of AM-fabricated parts are comprehensively compared and evaluated. Finally, several future research directions are suggested.

36 MATERIALS SCIENCE↗