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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 1,063 records · Page 59
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Fundamental Understanding and Material Challenges in Rechargeable Nonaqueous Li-O 2 Batteries: Recent Progress and Perspective

Energy storage challenges have triggered growing interest in various battery technologies and electrocatalysis. As a particularly promising variety, the Li–O 2 battery with an extremely high energy density is of great significance, offering tremendous opportunities to improve cell performance via understanding catalytic mechanisms and the exploration of new materials. Furthermore, focus on nonaqueous electrolyte–based Li–O 2 batteries has markedly intensified since there could be a higher probability of commercialization, compared to that of solid–state or aqueous electrolytes. The recent advancements of the nonaqueous Li–O 2 battery in terms of fundamental understanding and material challenges, including electrolyte stability, water effect, and noncarbon cathode materials are summarized in this review. Further, the current status of water impact on discharge products, possible mechanisms, and parasitic reactions in nonaqueous electrolytes are reviewed for the first time. The key challenges of noncarbon oxygen electrode materials, such as noble metals and metal oxide–based cathodes, transition metals, transition metal compounds (carbides, oxides) based cathodes as well as noncarbon supported catalysts are discussed. In conclusion, this review concludes with a perspective on future research directions for nonaqueous Li–O 2 batteries.

25 ENERGY STORAGE↗
DOE OSTI2018

Current concepts on epilepsy management in tuberous sclerosis complex

Tuberous sclerosis complex (TSC) is an autosomal dominant neurocutaneous disease affecting approximately 1 in 6,000 people, and represents one of the most common genetic causes of epilepsy. Epilepsy affects 90% of the patients and appears in the first 2 years of life in the majority of them. Early onset of epilepsy in the first 12 months of life is associated with high risk of cognitive decline and neuropsychiatric problems including autism. Prenatal or early infantile diagnosis of TSC, before the onset of epilepsy, provides a unique opportunity to monitor EEG before the onset of clinical seizures, thus enabling early intervention in the process of epileptogenesis. In this review, we discuss the current status of knowledge on epileptogenesis in TSC, and present recommendations of American and European experts in the field of epilepsy.

Canevini, Maria Paola↗
DOE OSTI2017

Rice straw as a feedstock for biofuels: Availability, recalcitrance, and chemical properties

The surplus availability of rice straw, its limited usage and environment pollution caused by inefficient burning has fostered research for its valorization to biofuels. This review elucidates the current status of rice straw potential around the globe along with recent advances in revealing the critical factors responsible for its recalcitrance and chemical properties. The role and accumulation of high silica content in rice straw has been elucidated with its impact on enzymatic hydrolysis in a biorefinery environment. The correlation of different pretreatment approaches in modifying the physiochemical properties of rice straw and improving the enzymatic accessibility has also been discussed. This study highlights new challenges, resolutions and opportunities for rice straw based biorefineries.

09 BIOMASS FUELS↗
DOE OSTI2018

Verification of 5D continuum gyrokinetic code COGENT: Studies of kinetic drift wave instability

COGENT (Continuum Gyrokinetic Edge New Technology) is a kinetic plasma simulation code that is being developed by the edge simulation laboratory (ESL) collaboration. The original version of the code has been developed in a 4D phase space (2D configuration space and 2D velocity space) to address kinetic plasma phenomena in a complex magnetic field geometry including the core, magnetic separatrix, and scrape-off layer regions. This paper is focused on extending the original 4D phase space to a 5D phase space (3D2V) to address full kinetic turbulences in a tokamak edge region. Here, we report on the current status of 5D COGENT, which presently operates in a shear-less, simple slab geometry. As a verification study, we use the problems of collision-less drift wave instability (universal instability) including its modification in the presence of collisional effects. The simulation model includes the gyrokinetic equations for ion and electron species coupled to the long-wavelength limit of the gyro-Poisson equation. Collisional effects are represented by the Krook collision model. Linear analytical results for the drift mode growth rate and real frequency are recovered, and the non-linear stage is modelled and analysed as well. In addition, extensive 5D runs have been performed to address the effects of the drift wave instability on blob/filamentary structures characteristic of a tokamak edge. Finally, a helical-shaped potential perturbation is observed to grow exponentially in time while spinning around the filament axis with electron drift frequency.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2015

Application of Physiologically Based Pharmacokinetic (PBPK) Modeling to Support Dose Selection: Report of an FDA Public Workshop on PBPK: Physiologically Based Pharmacokinetic Modeling to Support Dose Selection

A workshop entitled “Application of Physiologically-based Pharmacokinetic (PBPK) Modeling to Support Dose Selection” was hosted on March 10, 2014 by the US Food and Drug Administration (FDA) at its White Oak Campus in Silver Spring, MD.1 The workshop endeavored to (i) assess the current state of knowledge in the application of PBPK in regulatory decision-making, and (ii) share and discuss best practices in the use of PBPK modeling to inform dose selection in specific patient populations. The conference benefited from strong and diverse participation from the FDA Center for Drug Evaluation and Research (CDER) leaders, European Medicine Agency (EMA) delegates, and pharmaceutical industry and academia representatives. The workshop commenced with plenary presentations by speakers from the FDA, industry, and academia. In the two panel sessions, detailed questions on the current status and future applications of PBPK in drug development and regulatory decisions were discussed. An important focus of the dialog was the need to better define what constitutes a credible physiological system and the evidentiary standards needed for using such a system in making regulatory decisions. This report provides a content summary of the workshop, based on plenary presentations and panel session transcripts posted on the FDA’s website.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2016

High-Entropy Metallic Glasses

This chapter applies the concept of high entropy to metallic glasses (MGs), in particular, to those in a bulk shape: bulk metallic glasses (BMGs). The resultant target materials in this chapter are mainly high-entropy bulk metallic glasses (HE-BMGs), which have recently been developed as alloys with characteristics of both high-entropy alloys (HEAs) and BMGs. Here, the contents in this chapter start by introducing historic background of HE-BMGs and by summarizing the differences between HEAs and BMGs. Then, the fundamental properties of representative HE-BMGs found to date are described mainly in terms of thermodynamic and mechanical behaviors. Besides the experiments, the latest computational approach for clarifying the features of HE-BMGs is described based on the results using ab initio molecular dynamics simulations for the atomic structure, chemical interaction, and diffusivity in this unique class of materials. The current status and future prospects of the HE-BMGs by utilizing their unique features are outlined for their future applications.

36 MATERIALS SCIENCE↗
DOE OSTI2016

The Role of National Research and Education Networks Providing Connectivity and Advanced Network Services to Virtual Communities in Collaborative R&E Projects. CUDI: The Mexican Case Part 1, , In: ISUM 2015: High Performance Computer Applications

This paper describes the role of National Research and Education Networks (NRENs) and their aim to provide a seamless, large scale, high-speed, low-latency network to accelerate scientific and education discovery for national, regional or global collaborative projects that are dependent on the use of modern high performance distributed computing systems (HPDCS) to process mathematical models, produce new knowledge and drive innovation when resolving complex problems. NRENs have become the mainstream of communication and collaboration to integrate the efforts of large geographically distributed teams of Virtual Communities (VC) that - train, teach and learn-, -create, use and share- knowledge, data, information and communications technology resources (e.g. computer and information systems, middleware, tools, instruments, data sets, repositories, applications and services) building e-infrastructures necessary to meet the collaborative projects’ goals. The paper focuses on the current status of the Mexican NREN: CUDI, its future organization and political support, necessary to provide seamless, large scale, high-speed, low latency and secure national backbone and international links providing connectivity, advanced network services and technical support to VCs and their e-infrastructures in collaborative R&E projects within the country, the LAC region and worldwide.

Computer Science↗
DOE OSTI2013

Light Stops, Light Staus and the 125 GeV Higgs

The ATLAS and CMS experiments have recently announced the discovery of a Higgs-like resonance with mass close to 125 GeV. Overall, the data is consistent with a Standard Model (SM)-like Higgs boson. Such a particle may arise in the minimal supersymmetric extension of the SM with average stop masses of the order of the TeV scale and a sizable stop mixing parameter. In this article we discuss properties of the SM-like Higgs production and decay rates induced by the possible presence of light staus and light stops. Light staus can affect the decay rate of the Higgs into di-photons and, in the case of sizable left-right mixing, induce an enhancement in this production channel up to $\sim$ 50% of the Standard Model rate. Light stops may induce sizable modifications of the Higgs gluon fusion production rate and correlated modifications to the Higgs diphoton decay. Departures from SM values of the bottom-quark and tau-lepton couplings to the Higgs can be obtained due to Higgs mixing effects triggered by light third generation scalar superpartners. We describe the phenomenological implications of light staus on searches for light stops and non-standard Higgs bosons. Finally, we discuss the current status of the search for light staus produced in association with sneutrinos, in final states containing a $W$ gauge boson and a pair of $\tau$s.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2017

The GlueX Experiment: First Results

GlueX is a nuclear physics experiment located at the Thomas Jefferson National Accelerator Facility designed to study and understand the nature of confinement in QCD by mapping the spectrum of exotic mesons. The experiment will be able to probe new areas by using photoproduction, i.e. the scattering on nucleon of ~9 GeV linearly polarized photons derived from the recently upgraded CEBAF with a 12 GeV electron beam. Spring 2016 has been characterized by a continued detector commissioning and initial running at the full design energy. The current status of the GlueX detector performance and data collection will be discussed, with a brief overview of first physics results, future run plans, and long term upgrades.

Fanelli, Cristiano (ORCID:0000000219851329)↗
DOE OSTI2018

Nuclear-Physical Foundation of Atomic Energy

The current status of the nuclear database used for engineering calculations in the field of nuclear energy is reported. It is shown that the nuclear database and its attendant computational methods, stabilization, and transmission to the next generation of specialists who will have to solve the problems of the future development of nuclear power must be improved and updated.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2018

Nuclear Problems of Thermonuclear Power Generation

The current status of the nuclear problems of the thermonuclear fusion research program and, in particular, tritium, is discussed. It is noted that thermonuclear power generation without a uranium or thorium blanket is problematic; the key nuclear problems of the fusion–fission hybrid system remain unsolved. It is proposed that an integrated strategic analysis be made of the thermonuclear research program and the realistic possibilities of its application in nuclear power-engineering.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2018

Josephson Effects in Frequency-Domain Multiplexed TES Microcalorimeters and Bolometers

Frequency-division multiplexing is the baseline read-out system for large arrays of superconducting transition-edge sensors (TES’s) under development for the X-ray and infrared instruments like X-IFU (Athena) and SAFARI, respectively. In this multiplexing scheme, the sensors are ac-biased at different frequencies from 1 to 5 MHz and operate as amplitude modulators. Weak superconductivity is responsible for the complex TES resistive transition, experimentally explored in great detail so far, both with dc- and ac-biased read-out schemes. In this paper, we will review the current status of our understanding of the physics of the TES’s and their interaction with the ac bias circuit. In particular, we will compare the behaviour of the TES nonlinear impedance, across the superconducting transition, for several detector families, namely: high-normal-resistance TiAu TES bolometers, low-normal-resistance MoAu TES microcalorimeters and high-normal-resistance TiAu TES microcalorimeters.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2022

Latest Results from the CUORE Experiment

Abstract The Cryogenic Underground Observatory for Rare Events (CUORE) is the first cryogenic experiment searching for $$0\nu \beta \beta $$ 0 ν β β decay that has been able to reach the one-tonne mass scale. The detector, located at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy, consists of an array of 988 $${\mathrm{TeO}}_{2}$$ TeO 2 crystals arranged in a compact cylindrical structure of 19 towers. CUORE began its first physics data run in 2017 at a base temperature of about 10 mK and in April 2021 released its $$3{\mathrm{rd}}$$ 3 rd result of the search for $$0\nu \beta \beta $$ 0 ν β β , corresponding to a tonne-year of $$\mathrm{TeO}_{2}$$ TeO 2 exposure. This is the largest amount of data ever acquired with a solid state detector and the most sensitive measurement of $$0\nu \beta \beta $$ 0 ν β β decay in $${}^{130}\mathrm{Te}$$ 130 Te ever conducted . We present the current status of CUORE search for $$0\nu \beta \beta $$ 0 ν β β with the updated statistics of one tonne-yr. We finally give an update of the CUORE background model and the measurement of the $${}^{130}\mathrm{Te}$$ 130 Te $$2\nu \beta \beta $$ 2 ν β β decay half-life and decay to excited states of $${}^{130}\mathrm{Xe}$$ 130 Xe , studies performed using an exposure of 300.7 kg yr.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2017

Electrospinning: Polymer Nanofibre Adsorbent Applications for Metal Ion Removal

In recent decades, electrospun nanofibres have been applied to different potential fields such as sensor devices, tissue engineering scaffolds, wound dressing, filtration, drug delivery, etc. and significant review papers have been published in these fields. However, the use of electrospun nanofibres in metal ion adsorption is emerging and comparatively innovative. Nanofibre materials hold great potential in advancing the growth of metallurgical technologies and progress for the separation of metallic ions from various sources. The physico-chemical removal processes of adsorption use nanofibres due to their large surface area to volume ratio and the availability of a wide variety of chemical and morphological modification methods. In this review paper, research and developments related to electrospun polymer nanofibre for metal ion removal is presented. The review highlights the emerging and increasing use of electrospun nanofibres for metal ion adsorption especially for hazardous metals. Fundamental understanding of the electrospinning fabrication process, working parameters as they affect fibre morphologies, solvents and polymers used in electrospinning is discussed. This work summarizes the current status of process technique development and ideas in the research and use of electrospun nanofibres in heavy metal ion adsorption to address environmental problems from contaminated water.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2016

Current Thoughts on Reactive Element Effects in Alumina-Forming Systems: In Memory of John Stringer

In memory of John Stringer (1934–2014), one of the leaders in studying the reactive element (RE) effects, this paper reviews the current status of understanding of the effect of RE dopants on high-temperature oxidation behavior, with an emphasis on recent research related to deploying alumina-forming alloys and coatings with optimal performance in commercial systems. Additionally, to the well-known interaction between indigenous sulfur and RE additions, effects have been observed with C, N, and O found in commercial alloys and coatings. While there are many similarities between alumina-forming alloys and coatings, the latter bring additional complicating factors such as the effects of O incorporation during thermal spraying MCrAlY coatings, coating roughness, and heat treatments that must be considered in optimizing the beneficial dopant addition. We can see analogies between RE effects in alloys and in the substrates beneath diffusion M–Al coatings. Recently, there has been more interest in the influence of mixed oxidant environments, since these may modify the manifestation of the RE effect. Some thoughts are provided on optimizing the RE benefit and modeling oxidation of RE-doped alloys.

36 MATERIALS SCIENCE↗
DOE OSTI2025

CO2-Utilization Facilitated by Solid Reaction Mediums—A Review

Abstract This short review examines solid reaction mediums—specifically oxygen, CO 2 , and carbon carriers—within the framework of Chemical Looping (CL) to illuminate various CO 2 utilization pathways. The thermodynamic consideration for carrier selection is first discussed. This is followed by a summary of the key carrier types investigated to date, with an emphasis on elucidating the roles of compositional, structural, and surface properties of the various carriers toward their reactive performances. Besides assessing the performances of various oxygen carriers, their long-term performance, potential deactivation mechanism in the presence of CO 2, and strategies for their reactivation are also discussed in the context of chemical looping dry reforming of methane (CLDRM). While relatively underexplored, the current status of development, advantages, and potential limitations of CO 2 carriers in sorbent looping dry reforming of methane (SLDRM) and carbon carriers in chemical looping methane cracking (CLMC) are also reviewed and discussed. Emerging topics such as combined carriers are also covered along with a perspective for future research directions. Overall, this review aims to offer insights into the sustainable use of CO 2 through chemical looping, emphasizing the potential of solid reaction mediums across different carriers and the challenges associated with these solid reaction mediums.

Iftikhar, Sherafghan↗
DOE OSTI2016

The Materials Data Facility: Data Services to Advance Materials Science Research

With increasingly strict data management requirements from funding agencies and institutions, expanding focus on the challenges of research replicability, and growing data sizes and heterogeneity, new data needs are emerging in the materials community. The materials data facility (MDF) operates two cloudhosted services, data publication and data discovery, with features to promote open data sharing, self-service data publication and curation, and encourage data reuse, layered with powerful data discovery tools. The data publication service simplifies the process of copying data to a secure storage location, assigning data a citable persistent identifier, and recording custom (e.g., material, technique, or instrument specific)and automatically-extractedmetadata in a registrywhile the data discovery service will provide advanced search capabilities (e.g., faceting, free text range querying, and full text search) against the registered data and metadata. TheMDF services empower individual researchers, research projects, and institutions to (I) publish research datasets, regardless of size, from local storage, institutional data stores, or cloud storage, without involvement of thirdparty publishers; (II) build, share, and enforce extensible domain-specific custom metadata schemas; (III) interact with published data and metadata via representational state transfer (REST) application program interfaces (APIs) to facilitate automation, analysis, and feedback; and (IV) access a data discovery model that allows researchers to search, interrogate, and eventually build on existing published data. We describe MDF’s design, current status, and future plans.

data management↗
DOE OSTI2022

Manufacturing Processes for Permanent Magnets: Part II—Bonding and Emerging Methods

Abstract Permanent magnets produce magnetic fields and maintain the field even in the presence of an opposing magnetic field. They are widely used in electric machines, electronics, and medical devices. Part I reviews the conventional manufacturing processes for commercial magnets, including Nd-Fe-B, Sm-Co, alnico, and ferrite in cast and sintered forms. In Part II, bonding, emerging advanced manufacturing processes, as well as magnet recycling methods are briefly reviewed for their current status, challenges, and future directions.

Cui, Jun (ORCID:0000000179118172)↗