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All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Advanced Scientific Computing Research Network Requirements: ASCR Network Requirements Review Final Report

The Energy Sciences Network (ESnet) is the primary provider of network connectivity for the U.S. Department of Energy (DOE) Office of Science (SC), the single largest supporter of basic research in the physical sciences in the United States. In support of SC programs, ESnet regularly updates and refreshes its understanding of the networking requirements of the instruments, facilities, scientists, and science programs that it serves. This focus has helped ESnet to be a highly successful enabler of scientific discovery for over 25 years. In October 2012, ESnet and the Office of Advanced Scientific Computing Research (ASCR) of the DOE SC organized a review to characterize the networking requirements of the programs funded by the ASCR program office. The requirements identified at the review are summarized in the Findings section, and are described in more detail in the body of the report.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2015

Giant Electrocaloric Effect in Ferroelectrics with Tailored Polaw-Nanostructures

Electrocaloric effect (ECE) is the temperature and/or entropy change in a dielectric material caused by an electric field induced polarization change. Although ECE has been studied since 1930s, the very small ECE observed in earlier studies in bulk materials before 2007 makes it not attractive for practical cooling applications. The objectives of this DOE program are to carry out a systematical scientific research on the entropy change and ECE in polar-dielectrics, especially ferroelectrics based on several fundamental hypotheses and to search for answers on a few scientific questions. Especially, this research program developed a series of polar-dielectric materials with controlled nano- and meso-structures and carried out studies on how these structures affect the polar-ordering, correlations, energy landscapes, and consequently the entropy states at different phases and ECE. The key hypotheses of the program include: (i) Whether a large ECE can be obtained near the ferroelectric-paraelectric (FE-PE) transition in properly designed ferroelectrics which possess large polarization P and large ß (the coefficient in the thermodynamic Landau theory where the Gibbs free energy G = G = G 0 + ½ a P 2 +1/4 b P 4 + 1/6 c P 6 – EP, and a = ß (T-T c ), where b,c,ß and Tc are constants)? (ii) What determines/determine ß? Whether a ferroelectric material with built-in disorders, which disrupt the polar-correlations and enabling a large number of local polar-states, such as a properly designed ferroelectric relaxor, can achieve a large ECE? (iii) How to design a ferroelectric material which has flat energy landscape so that the energy barriers for switching among different phases are vanishingly small? What are the necessary conditions to maximize the number of coexisting phases? (iv) How to design ferroelectric materials with a large tunable dielectric response? That is, at zero electric field, the material possesses very low polar-correlation and hence a very small dielectric constant, under the application of electric field, the material develops long range polar-correlation and hence a high dielectric response. Studying and developing these materials will deepen our understanding on the polarization responses in strongly coupled materials and the roles of molecular and nano, meso-, and micro-scale defects and structures on the polarization responses. On the application front, besides ECE, these dielectrics will also have great impact on micro-electronics and communications. (v) The multi-field effect, besides the electric, elastic and even magnetic effects, could be made use of to tune the energy landscape of polar-materials and hence enhance the ECE. Hence the question is what are the suitable material systems to develop and maximize the multi-field effects? (vi) Besides solid dielectric, liquid dielectrics with properly designed molecular structures and dipolar coupling can also exhibit a large ECE near the dipolar order-disorder transition. The study of order-disorder transition and their influence on entropy change and ECE will provide additional avenue to study dielectrics and understand relationship between the polar-ordering and dipolar entropy in dielectrics. (vii) Besides the regular ECE in which applying an electric field will induce dipolar ordering, there are dielectric material systems which can exhibit negative ECE in which the applied field will reduce the dipolar ordering and anomalous ECE in which applying an electric field pulse will generate cooling only. The question is how to control and balance the nano- and meso-scale polar coupling in dielectrics to achieve such effects? ECE in dielectrics provides an interesting and effective avenue to probe the polar-correlation in dielectrics. Thus the study of ECE in polar-dielectrics, besides the application values, will also deepen our understanding of strongly coupled materials systems, phase transitions, and materials systems with nano- and meso-scale disorders. Through the efforts of this DoE program, we have developed understandings for many questions and materials approaches for many hypotheses listed above. The major accomplishments include: (i) The first one to show that a giant ECE can be obtained in bulk materials of ferroelectric P(VDF-TrFE) copolymer, which has a large ß coefficient and high polarization, near FE-PE transition.[1,3,12] (ii) The first who developed the theoretical analyses on the upper bound of dipolar entropy change in polar-materials and the general approach to maximize the coexisting phases with vanishingly small switching fields among the coexisting phases[10,23] Experimental results confirm these theoretical predictions.[24] (iii) The first to show that the relaxor ferroelectrics, due to built-in defects structures at nano- and meso scale, exhibit a giant ECE over a broad temperature range.[1,3,7,14] (iv) The first to show that a large ECE can be obtained near order-disorder transition in dielectric fluids such as liquid crystals with large dielectric anisotropy. Also the study developed a general approach for developing dielectric fluids to achieve a large electric field induced entropy change.[26] (v) We are starting to explore the multi-field effect (multiferroic effect) in nanocomposites in which there exist large dielectric contrasts between the matrix and nanofilelrs and showed that a significantly enhanced ECE compared with polymer matrix.[36] (vi) By facially tuning the nano- and meso-scale dipolar coupling, we are the first to show that an anomalous ECE can be obtained in a relaxor/normal ferroelectric blend.[39] (vii) Introduced and demonstrated that the internal bias field approach can be effective in enhancing the EC response at low electric field. The result is significant since for practical applications, a low applied field is highly desired. (viii) A high sensitivity ECE characterization system has been developed. This program has made major contributions to the advancement of the EC materials and understandings of EC phenomena. To reflect the advancement in the EC materials development and scientific understandings on ECE through in this time period (from Sept. 1, 2007 to May 2015), this final report is written based on the reports complied each year through the program. Some early works on the ECE which were obtained using the indirect method are not included in this report.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Lewis Acid Pairs for the Activation of Biomass-derived Oxygenates in Aqueous Media

The objective of this project is to understand the mechanistic aspects behind the cooperative activation of oxygenates by catalytic pairs in aqueous media. Specifically, we will investigate how the reactivity of a solid Lewis acid can be modulated by pairing the active site with other catalytic sites at the molecular level, with the ultimate goal of enhancing activation of targeted functional groups. Although unusual catalytic properties have been attributed to the cooperative effects promoted by such catalytic pairs, virtually no studies exist detailing the use heterogeneous water-tolerant Lewis pairs. A main goal of this work is to devise rational pathways for the synthesis of porous heterogeneous catalysts featuring isolated Lewis pairs that are active in the transformation of biomass-derived oxygenates in the presence of bulk water. Achieving this technical goal will require closely linking advanced synthesis techniques; detailed kinetic and mechanistic investigations; strict thermodynamic arguments; and comprehensive characterization studies of both materials and reaction intermediates. For the last performance period (2014-2015), two technical aims were pursued: 1) C-C coupling using Lewis acid and base pairs in Lewis acidic zeolites. Tin-, zirconium-, and hafnium containing zeolites (e.g., Sn-, Zr-, and Hf-Beta) are versatile solid Lewis acids that selectively activate carbonyl functional groups. In this aim, we demonstrate that these zeolites catalyze the cross-aldol condensation of aromatic aldehydes with acetone under mild reaction conditions with near quantitative yields. NMR studies with isotopically labeled molecules confirm that acid-base pairs in the Si-O-M framework ensemble promote soft enolization through α-proton abstraction. The Lewis acidic zeolites maintain activity in the presence of water and, unlike traditional base catalysts, in acidic solutions. 2) One-pot synthesis of MWW zeolite nanosheets for activation of bulky substrates. Through post-synthetic modifications, layered zeolite precursors can be transformed into 2-dimensional (2D), zeolites with open architectures. These novel hierarchical microporous/mesoporous materials with exposed active sites can facilitate the conversion of bulky substrates while maintaining higher stability than amorphous mesoporous materials. However, post-synthetic exfoliation techniques are energy intensive, multi-step and require highly alkaline conditions that result in low silica yields and a partially amorphous product. In this aim, we demonstrate an effective one-pot synthesis method to generate exfoliated single-unit-cell thick MWW nanosheets. The new material, named MIT-1, is synthesized using a rationally-designed OSDA and results in a material with high crystallinity, surface area, and acidity that does not require post-synthetic treatments other than calcination. A parametric study of Al, Na, and water content reveals that MIT-1 crystallizes over a wide synthetic window. Characterization data show that MIT-1 has high mesoporosity with an external surface area exceeding 500 m2g-1 and a high external acid site density of 21 x 10-5 mol g-1. Catalytic tests demonstrate that MIT-1 has three-fold higher catalytic activity for the Friedel-Crafts alkylation of benzene with benzyl alcohol as compared to that of other 3D MWW topology zeolites.

09 BIOMASS FUELS↗
DOE OSTI2015

Controlling Subsurface Fractures and Fluid Flow: A Basic Research Agenda

From beneath the surface of the earth, we currently obtain about 80-percent of the energy our nation consumes each year. In the future we have the potential to generate billions of watts of electrical power from clean, green, geothermal energy sources. Our planet’s subsurface can also serve as a reservoir for storing energy produced from intermittent sources such as wind and solar, and it could provide safe, long-term storage of excess carbon dioxide, energy waste products and other hazardous materials. However, it is impossible to underestimate the complexities of the subsurface world. These complexities challenge our ability to acquire the scientific knowledge needed for the efficient and safe exploitation of its resources. To more effectively harness subsurface resources while mitigating the impacts of developing and using these resources, the U.S. Department of Energy established SubTER – the Subsurface Technology and Engineering RD&D Crosscut team. This DOE multi-office team engaged scientists and engineers from the national laboratories to assess and make recommendations for improving energy-related subsurface engineering. The SubTER team produced a plan with the overall objective of “adaptive control of subsurface fractures and fluid flow.”This plan revolved around four core technological pillars—Intelligent Wellbore Systems that sustain the integrity of the wellbore environment; Subsurface Stress and Induced Seismicity programs that guide and optimize sustainable energy strategies while reducing the risks associated with subsurface injections; Permeability Manipulation studies that improve methods of enhancing, impeding and eliminating fluid flow; and New Subsurface Signals that transform our ability to see into and characterize subsurface systems. The SubTER team developed an extensive R&D plan for advancing technologies within these four core pillars and also identified several areas where new technologies would require additional basic research. In response, the Office of Science, through its Office of Basic Energy Science (BES), convened a roundtable consisting of 15 national lab, university and industry geoscience experts to brainstorm basic research areas that underpin the SubTER goals but are currently underrepresented in the BES research portfolio. Held in Germantown, Maryland on May 22, 2015, the round-table participants developed a basic research agenda that is detailed in this report. Highlights include the following: -A grand challenge calling for advanced imaging of stress and geological processes to help understand how stresses and chemical substances are distributed in the subsurface—knowledge that is critical to all aspects of subsurface engineering; -A priority research direction aimed at achieving control of fluid flow through fractured media; -A priority research direction aimed at better understanding how mechanical and geochemical perturbations to subsurface rock systems are coupled through fluid and mineral interactions; -A priority research direction aimed at studying the structure, permeability, reactivity and other properties of nanoporous rocks, like shale, which have become critical energy materials and exhibit important hallmarks of mesoscale materials; -A cross-cutting theme that would accelerate development of advanced computational methods to describe heterogeneous time-dependent geologic systems that could, among other potential benefits, provide new and vastly improved models of hydraulic fracturing and its environmental impacts; -A cross-cutting theme that would lead to the creation of “geo-architected materials” with controlled repeatable heterogeneity and structure that can be tested under a variety of thermal, hydraulic, chemical and mechanical conditions relevant to subsurface systems; -A cross-cutting theme calling for new laboratory studies on both natural and geo-architected subsurface materials that deploy advanced high-resolution 3D imaging and chemical analysis methods to determine the ;rates and mechanisms of fluid-rock processes, and to test predictive models of such phenomena. Many of the key energy challenges of the future demand a greater understanding of the subsurface world in all of its complexity. This greater under- standing will improve the ability to control and manipulate the subsurface world in ways that will benefit both the economy and the environment. This report provides specific basic research pathways to address some of the most fundamental issues of energy-related subsurface engineering.

15 GEOTHERMAL ENERGY↗
DOE OSTI2019

Predictive Capabilities, Analysis and Experiments for Fusion Nuclear Science and Plasma Chamber Research

UCLA led the efforts of the US on Fusion Nuclear Science and Technology (FNST) for the past 35 years and is the recognized leader of FNST research. UCLA research focuses on identifying and characterizing the key FNST issues with high scientific content, performing pioneering experiments and advancing modelling capabilities, and has led many pioneering domestic and international studies on FNST that greatly advanced the FNST field. Examples of major achievements include our leadership and research work in: FINESSE: Seminal contribution to defining the FNST issues and research approach APEX: High power density concepts including free surface liquid walls and divertors FNSF/VNS: Need for and definition of FSNF conceived and pioneered by UCLA US ITER Test Blanket Program: Defined the test program with international community and options for US participation US-JA JUPITER and TITAN research collaborations: First of a kind research on Molten salt MHD and other advanced functional materials UCLA-EUROfusion collaboration: construction of a first-of-a-kind multiple effect LM-MHD-Thermofluid test facility The achievements and the associated publications during the current grant period of 2/1/2017 to 01/31/2019 are summarized in this final report for the following research areas: First experiments on a First-of-a-Kind Multiple-effect Facility in Liquid Metal MHD Research Self-Generated Stress Evolutions in Ceramic Breeder Material System Thermomechanics Integrated Model for Tritium Transport and Permeation Predictions FESS Liquid Wall Study The people working on the project during this period are listed in Section III. There is no unexpended funds at the final budget period.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2017

Basic Research Needs for Catalysis Science to Transform Energy Technologies: Report from the U.S. Department of Energy, Office of Basic Energy Sciences Workshop May 8–10, 2017, in Gaithersburg, Maryland

Energy technologies affect virtually every aspect of life in modern societies—including transportation, utilities, agriculture, medicine, and the availability of a myriad of consumer products—and depend on human ability to accelerate and to guide chemical transformations. Controlling these transformations, which occur in the microscopic world of atoms and molecules, forms the basis of countless technologies such as production of fuels, fertilizers, plastics, pharmaceuticals and much more. At the very core of these chemical transformations are catalysts—specialized and often highly complex types of matter that allow chemical reactions to occur rapidly and produce specific products. Catalysts also have the remarkable ability to perform their tasks millions of times without themselves being consumed. The discovery of inexpensive and widely-deployable energy and chemical technologies, and their underpinning catalysis science, is critical to ensure the economic viability of U.S. energy and chemical industries. Over the past decade, remarkable new tools have been discovered that allow the observation of catalytic transformations in exquisite detail, and assembly of novel and elaborate catalytic architectures with atomic precision. Furthermore, increasingly sophisticated theoretical and computational tools allow understanding of the essential details of the catalytic processes, and this overall progress has led to the discovery of catalysts with superior performance and the associated economic benefit. In the next decade and beyond, science promises to revolutionize how catalysts and catalytic processes are designed, to enable the introduction of new energy resources, to provide routes to sustainable synthesis of chemicals and other valuable materials, and to create novel approaches to chemical energy storage. This report is the result of the Basic Energy Sciences Workshop on Basic Research Needs for Catalysis Science to Transform Energy Technologies that was held in May 2017, and was attended by more than 100 leading national and international scientific experts. The attendees were organized into four panels: 1. Diversified Energy Feedstocks and Carriers, 2. Novel Approaches to Energy Transformations, 3. Advanced Chemical Conversion Approaches, and 4. Crosscutting Capabilities and Challenges: Synthesis, Theory, and Characterization. The workshop identified five priority research directions (PRDs) that are aimed at harnessing complexity in catalysis to create next-generation energy technologies and realizing efficient catalytic processes to increase the diversity of resources for production of chemicals and energy.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

ARM FY2026 Radar Plan

The U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) User Facility maintains a suite of advanced atmospheric radar systems that serve as critical tools in ARM’s mission to provide continuous, high-quality observations for advancing the understanding and modeling of atmospheric processes. These radar systems enable detailed characterization of clouds, precipitation, and dynamic structures in the atmosphere, supporting a broad range of scientific applications. The number of deployed systems exceeds what current staffing levels can fully support for continuous 24/7/365 operation. As such, it is essential to have a clearly defined and community-informed plan that prioritizes radar operations and communicates ARM’s strategy for sustaining and evolving these observational assets. This FY2026 Radar Plan outlines ARM’s approach to managing its radar portfolio—balancing scientific impact, operational feasibility, and long-term sustainability. It reflects ARM’s continued commitment to delivering calibrated, well-documented radar data products that enable process-level studies and support the development and evaluation of weather and climate models. Through this plan, ARM aims to ensure transparency in decision-making, alignment with user needs, and support for innovative science across the facility’s fixed and mobile observatories. Given uncertainties around the Fiscal Year (FY) 2026 budget, this plan was developed to assume business as usual and will be updated as budgets and plans may change. It should be noted that, given the limited timeframe involved, this plan will be more succinct than previous plans.

47 OTHER INSTRUMENTATION↗
DOE OSTI2014

Overview of the Focused Isoprene eXperiment at the California Institute of Technology (FIXCIT): mechanistic chamber studies on the oxidation of biogenic compounds

The Focused Isoprene eXperiment at the California Institute of Technology (FIXCIT) was a collaborative atmospheric chamber campaign that occurred during January 2014. FIXCIT is the laboratory component of a synergistic field and laboratory effort aimed toward (1) better understanding the chemical details behind ambient observations relevant to the southeastern United States, (2) advancing the knowledge of atmospheric oxidation mechanisms of important biogenic hydrocarbons, and (3) characterizing the behavior of field instrumentation using authentic standards. Approximately 20 principal scientists from 14 academic and government institutions performed parallel measurements at a forested site in Alabama and at the atmospheric chambers at Caltech. During the 4 week campaign period, a series of chamber experiments was conducted to investigate the dark- and photo-induced oxidation of isoprene, α-pinene, methacrolein, pinonaldehyde, acylperoxy nitrates, isoprene hydroxy nitrates (ISOPN), isoprene hydroxy hydroperoxides (ISOPOOH), and isoprene epoxydiols (IEPOX) in a highly controlled and atmospherically relevant manner. Pinonaldehyde and isomer-specific standards of ISOPN, ISOPOOH, and IEPOX were synthesized and contributed by campaign participants, which enabled explicit exploration into the oxidation mechanisms and instrument responses for these important atmospheric compounds. The present overview describes the goals, experimental design, instrumental techniques, and preliminary observations from the campaign. This work provides context for forthcoming publications affiliated with the FIXCIT campaign. Insights from FIXCIT are anticipated to aid significantly in interpretation of field data and the revision of mechanisms currently implemented in regional and global atmospheric models.

Nguyen, T. B.↗
DOE OSTI2024

An Update on Project PARETO - New Capabilities in DOE's Produced Water Optimization Framework

Managing oil and gas produced water, characterized by hypersalinity and large volumes, presents significant challenges. This paper introduces an advanced optimization framework, PARETO, which offers a novel approach to strategic water management, emphasizing produced water (PW) treatment, quality tracking, quantification of emissions, and environmental justice. This work pre-sents a case study showcasing different produced water management challenges. The PARETO framework demonstrated its effectiveness in optimizing water management strategies in line with environmental sustainability and regulatory compliance.

Zamarripa, Miguel↗
DOE OSTI2010

Challenges, uncertainties and issues facing gas production from gas hydrate deposits

The current paper complements the Moridis et al. (2009) review of the status of the effort toward commercial gas production from hydrates. We aim to describe the concept of the gas hydrate petroleum system, to discuss advances, requirement and suggested practices in gas hydrate (GH) prospecting and GH deposit characterization, and to review the associated technical, economic and environmental challenges and uncertainties, including: the accurate assessment of producible fractions of the GH resource, the development of methodologies for identifying suitable production targets, the sampling of hydrate-bearing sediments and sample analysis, the analysis and interpretation of geophysical surveys of GH reservoirs, well testing methods and interpretation of the results, geomechanical and reservoir/well stability concerns, well design, operation and installation, field operations and extending production beyond sand-dominated GH reservoirs, monitoring production and geomechanical stability, laboratory investigations, fundamental knowledge of hydrate behavior, the economics of commercial gas production from hydrates, and the associated environmental concerns.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2012

Development of Scanning Near-Field Ultrasound Holography as an Add-On Module for AFM systems

The project aimed to develop a standalone module for Atomic Force Microscope systems that the biological and environmental research community could use to image and quantify to a greater extent the interactions between nanoparticles and cells. If successful, it would enable the thousands of biological and environmental researchers with access to atomic force microscopes to perform scanning near field ultrasound holography to image nanoparticle interactions with cells. Over the course of this effort, grantees were able to develop a standalone module capable of performing scanning near field ultrasound holography on a variety of commercial systems. The add-on module was tested on systems from 3 of the major Atomic Force Microscope manufacturers (Veeco, JEOL and Park Systems). Furthermore, the investigators believe that the hardware developed will be capable of performing the technique on any AFM with standard signal access modules. The discrete components previously used to perform the SNFUH technique could cost upward of $\$$40,000. Beyond the cost issue, the components are bulky and cumbersome to work with because of the wiring needed between each of the components when implementing the technique. NanoSonix was able to dramatically reduce both the cost and complexity of implementing SNFUH, developing two functional versions of an add-on module (A&B) using National Instruments hardware as put forth in the proposal. More significantly, NanoSonix exceeded the aims of the proposal by developing completely custom electronics that should enable an almost order of magnitude cost reduction while improving the capability versus the discrete componentry. Because potential biological systems are so complex, biological applications of the technique are very diverse and require very distinct domain knowledge. This inhibits the utilization widespread adoption and penetration of new metrology techniques. Northwestern University and NanoSonix has made it both possible and practical for widespread adoption of the technique through the development of a standalone system with order of magnitude cost reduction and significant reduction in complexity. NanoSonix believes that it can produce the add-on modules and make them available to the academic research community at a price point below $\$$10,000, thereby enabling the biological research community to hardness the over 30,000 AFMs in existence around the world today, approximately 18,000 of which reside in the United States at a very modest incremental cost. Finally, we were able to implement a multi-frequency function generator and simultaneous multi-frequency lock-in amplifier with an internal reference frequency (which significantly simplifies the experimental setup) that it believes could lay the foundation for future non-destructive nanoscale 3-D tomography of buried and embedded sub-structures in cells and tissues. To date, we has been unable to find multiple frequency combinations which yield sufficiently strong mixing at the tip-sample interaction, but believes it is conceptually possible and doing so would enable the use of frequency dependent phase shift to better characterize the subsurface structures. Taken together, we believes that this work has materially advanced the prospects of enabling researchers to develop time-resolved cellular uptake of the nanoparticles used for drug delivery, cancer therapies, gene delivery and gene silencing and to assess cellular uptake of nanoparticles for environmental monitoring/remediation/impact.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2016

Spherical nanoindentation stress-strain analysis, Version 1

Nanoindentation is a tool that allows the mechanical response of a variety of materials at the nano to micron length scale to be measured. Recent advances in spherical nanoindentation techniques have allowed for a more reliable and meaningful characterization of the mechanical response from nanoindentation experiments in the form on an indentation stress-strain curve. This code base, Spin, is written in MATLAB (The Mathworks, Inc.) and based on the analysis protocols developed by S.R. Kalidindi and S. Pathak [1, 2]. The inputs include the displacement, load, harmonic contact stiffness, harmonic displacement, and harmonic load from spherical nanoindentation tests in the form of an Excel (Microsoft) spreadsheet. The outputs include indentation stress-strain curves and indentation properties as well their variance due to the uncertainty of the zero-point correction in the form of MATLAB data (.mat) and figures (.png). [1] S. Pathak, S.R. Kalidindi. Spherical nanoindentation stress–strain curves, Mater. Sci. Eng R-Rep 91 (2015). [2] S.R. Kalidindi, S. Pathak. Determination of the effective zero-point and the extraction of spherical nanoindentation stress-strain curves, Acta Materialia 56 (2008) 3523-3532.

Weaver, Jordan S.↗
DOE OSTI2021

High Entropy Alloys: Irradiation

High entropy alloys (HEAs) have been considered as structural materials for nuclear applications due to their promising mechanical properties and radiation resistance. For this purpose, irradiation-induced defect evolution and microstructure change have been characterized to evaluate the irradiation performance of different HEAs. This article reviews recent advances in understanding the irradiation response of HEAs, including the effect of disordered states on the defect energy landscape and defect evolution, irradiation-induced microstructure changes, void swelling, phase stability, mechanical properties under irradiation, as well as the He irradiation effects.

Zhao, Shijun↗
DOE OSTI2012

Improved LWR Cladding Performance by EPD Surface Modification Technique

This project will utilize the electro-phoretic deposition technique (EPD) in conjunction with nanofluids to deposit oxide coatings on prototypic zirconium alloy cladding surfaces. After demonstrating that this surface modification is reproducible and robust, the team will subject the modified surface to boiling and corrosion tests to characterize the improved nucleate boiling behavior and superior corrosion performance. The scope of work consists of the following three tasks: The first task will employ the EPD surface modification technique to coat the surface of a prototypic set of zirconium alloy cladding tube materials (e.g. Zircaloy and advanced alloys such as M5) with a micron-thick layer of zirconium oxide nanoparticles. The team will characterize the modified surface for uniformity using optical microscopy and scanning-electron microscopy, and for robustness using standard hardness measurements. After zirconium alloy cladding samples have been prepared and characterized using the EPD technique, the team will begin a set of boiling experiments to measure the heat transfer coefficient and critical heat flux (CHF) limit for each prepared sample and its control sample. This work will provide a relative comparison of the heat transfer performance for each alloy and the surface modification technique employed. As the boiling heat transfer experiments begin, the team will also begin corrosion tests for these zirconium alloy samples using a water corrosion test loop that can mimic light water reactor (LWR) operational environments. They will perform extended corrosion tests on the surface-modified zirconium alloy samples and control samples to examine the robustness of the modified surface, as well as the effect on surface oxidation

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2020

Characterization of groove density variation of VLS gratings with ALS XROL LTP-II in different operation modes

The long trace profiler, LTP-II, available at the Advanced Light Source (ALS) X-ray Optics Laboratory (XROL), was recently upgraded by replacing a multimode diode laser light source with a single-mode, wavelength-stabilized, fibercoupled diode laser system. The upgrade enables us to reliably characterize the lateral variation of groove density of variable-line-spacing (VLS) x-ray diffraction gratings. Here, we discuss the LTP-II performance with an example of measurements with a VLS grating with the groove density at the grating center of 300 lines/mm. For the measurements, we use the LTP-II in two different operation arrangements, the single Gaussian beam and the pencil beam interferometer arrangements. For each operation arrangement, we apply two data processing algorithms: with calculating the centroid position and with determining the position of a characteristic features of the detected beam intensity distributions. Additionally, we discuss the observed strong correlation between the LTP-II modes of operation and the resulted (extracted) groove density variations. We also speculate on possible origin of the correlation.

42 ENGINEERING↗
DOE OSTI2014

Comparison of a Traditional Probabilistic Risk Assessment Approach with Advanced Safety Analysis

As part of the Light Water Sustainability Program (LWRS) [1], the purpose of the Risk Informed Safety Margin Characterization (RISMC) [2] Pathway research and development (R&D) is to support plant decisions for risk-informed margin management with the aim to improve economics, reliability, and sustain safety of current NPPs. In this paper, we describe the RISMC analysis process illustrating how mechanistic and probabilistic approaches are combined in order to estimate a safety margin. We use the scenario of a “station blackout” (SBO) wherein offsite power and onsite power is lost, thereby causing a challenge to plant safety systems. We describe the RISMC approach, illustrate the station blackout modeling, and contrast this with traditional risk analysis modeling for this type of accident scenario. We also describe our approach we are using to represent advanced flooding analysis.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2022

Advancing flexible electronics and additive manufacturing

There is high interest in the synergism of thin-film and flexible electronics with additive manufacturing. This review primarily focuses on the prospective developments in convergence with flexible electronics manufacturing technologies. Specifically, this paper covers the latest 3D printing and hybrid manufacturing technologies, the utility of specific types of materials, their functionalization and characterization, post-processing and testing strategies toward fabricating robust and application-specific flexible electronics. Besides exploring the advances in this area of research—it also highlights the limitations and gaps that have been observed in the previous years that will challenge and offer opportunities for advancing research and development. Lastly, the future of 3D-printed flexible electronics is discussed in the aspects of customizability, scalability, and its game-changing and state-of-the-art potential for intelligent sensing, instrumentation, and wearables for various medical, engineering, and industrial applications.

36 MATERIALS SCIENCE↗