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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Li 2 GeS 3 : Lithium Ionic Conductor with an Unprecedented Structural Type

Lithium-ion batteries (LIBs) are widely used in electric vehicles, mobile electronic devices, and large-scale stationary energy storage systems. However, their liquid electrolytes present significant safety concerns due to their inherent flammability. To address this, the focus has shifted toward all-solid-state batteries (ASSBs) utilizing inorganic solid electrolytes that promise enhanced safety. In this work, we report the discovery of a new crystal structural type of Li-ion conductor, Li 2 GeS 3 , with a unique structure, synthesized by a solid-state reaction from Li 2 S and GeS 2 . It was first reported in 2000 with an orthorhombic unit cell, but its detailed crystal structure remains veiled. Here, we have unveiled its structure for the first time, employing an ab initio structure determination technique from powder X-ray and time-of-flight neutron diffraction data. The compound has an unprecedented crystal structural type with a hexagonal $P6_1$ symmetry and a unit cell of α = 6.79364(4) Å and c = 17.90724(14) Å. Its structure is comprised of a distorted hexagonal close-packed arrangement of sulfur anions with three asymmetric metal atoms: Li1, Li2, and Ge are in tetrahedral cavities surrounded by sulfur atoms. The ionic conductivity of Li 2 GeS 3 was measured to be 1.63 × 10 –8 S cm –1 at 303 K and 2.45 × 10 –7 S cm –1 at 383 K. Bond valence energy landscape calculations revealed three-dimensional lithium diffusion pathways within the structure. This novel crystal structure in Li 2 GeS 3 holds the potential for developing high-performance ionic conductors through suitable chemical substitution and offers valuable insights into designing new ionic conductors for ASSBs.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Crowdsourcing Felt Reports Using the MyShake Smartphone App

MyShake is a free citizen science smartphone app that provides a range of features related to earthquakes. Features available globally include rapid postearthquake notifications, live maps of earthquake damage as reported by MyShake users, safety tips, and various educational features. The app also uses the accelerometer in the mobile device to detect earthquake shaking, and to record and submit waveforms to a central archive. In addition, MyShake delivers earthquake early warning alerts in California, Oregon, and Washington. Here, in this study, we compare the felt shaking reports provided by MyShake users in California with the U.S. Geological Survey’s (USGSs) “Did You Feel It?” intensity reports. The MyShake app simply asks, “What strength of shaking did you feel?” and users report on a five-level scale. When the MyShake reports are averaged in spatial or time bins, we find strong correlation with the Modified Mercalli Intensity scale values reported by the USGS based on the DYFI surveys. The MyShake felt reports can therefore contribute to the creation of shaking intensity maps.

58 GEOSCIENCES↗
DOE OSTI2014

Requirements Document for the Redesign of the DIM-based Diagnostics Transport and Handling System at the National Ignition Facility (NIF)

The National Ignition Facility (NIF, Figure 1) is the world’s leading user research facility for inertial confinement fusion. Diagnostic instruments that collect data from the experiment shots are transported around the facility using a series of disjointed, suboptimal transport and handling (T&H) subsystems that compromise user efficiency and ergonomics. Significant time savings and improvements to the diagnostic exchange process could be realized by designing a new transport and handling system that minimizes the hand-offs between T&H subsystems, reduces operator hassle and ergonomic strain, and improves the long-term maintainability of the system. In contrast to the current system – which employs several manually-operated carts and containers to transport the diagnostic, dock it to its destination, and install it – the new diagnostic transporter integrates the contamination container with the transport cart and provides a dynamic range of adjustability to interface with its destination. This single transporter has the requisite maneuverability, height adjustability, and fine adjustment capabilities without any rigging transactions to support contaminated diagnostic transport and handling at the alignment station and Equatorial and Polar DIMs. A remote-controlled user interface device allows operators a more hands-off experience that reduces ergonomic strain and improves safety. Assuming the cost is not prohibitive, diagnostic storage will be accomplished by simply stowing the transporter in its lowest position in the designated area of NIF. This concept for a new diagnostic transport and handling system would be better aligned with the core values of NIF: safety, quality, and reliability.

42 ENGINEERING↗
DOE OSTI2011

How DARHT Works - the World's Most Powerful X-ray Machine

The Dual Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory is an essential scientific tool that supports Stockpile Stewardship at the Laboratory. The World's most powerful x-ray machine, it's used to take high-speed images of mock nuclear devices - data that is used to confirm and modify advanced computer codes in assuring the safety, security, and effectiveness of the U.S. nuclear deterrent.

43 PARTICLE ACCELERATORS↗
DOE OSTI2011

Dust Accelerators And Their Applications In High-Temperature Plasmas

The perennial presence of dust in high-temperature plasma and fusion devices has been firmly established. Dust inventory must be controlled, in particular in the next-generation steady-state fusion machines like ITER, as it can pose significant safety hazards and potentially interfere with fusion energy production. Although much effort has been devoted to getting rid of the dust nuisance, there are instances where a controlled use of dust can be beneficial. We have recognized a number of dust-accelerators applications in magnetic fusion, including in plasma diagnostics, in studying dust-plasma interactions, and more recently in edge localized mode (ELM)'s pacing. With the applications in mind, we will compare various acceleration methods, including electrostatic, gas-drag, and plasma-drag acceleration. We will also describe laboratory experiments and results on dust acceleration.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2021

Tier 2 Safety Basis Document: Weapons and Complex Integration - Building 225

This Safety Basis Document (SBD) covers operations in the Weapons and Complex Integration (WCI) Building 225 (B225) facility. B225 is located in the southwestern quadrant of Lawrence Livermore National Laboratory (LLNL) and is operated and owned by WCI. This SBD satisfies the requirements of LLNL ES&H Manual Document 3.1, Nonnuclear Safety Basis Program (Ref. 2). B225 is classified as a Low Hazard Facility based on the inventory of radiological materials. Other hazards in B225: chemicals, radiation generating devices, and industrial hazards are managed at the Light Science and Industry (LSI) level. Biological and explosive hazards are not authorized in B225. There are four general Administrative Controls (ACs) identified as the B225 Operational Safety Requirements (OSRs). These administrative controls are deemed sufficient to ensure safe operations with respect to co-located workers and the public. Other safety features and administrative requirements are required by the LLNL ES&H Manual, including those to protect the facility workers and the environment, but these have not been selected as credited controls to protect the co-located workers or the public, which are the target populations of concern for the SBD.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2016

Research and Experiment on the Key Technologies of the Spent Fuel Storage in HTR-PM - 18486

High Temperature Reactor demonstration project of China (HTR-PM) is one of the major national science and technology projects, some key technologies for the design and operation of the demonstration project are formed to research according to the main technology. The spent fuel storage system is one of the main systems of the HTR-PM. In order to solve the technical problems related to the operation of spent fuel, several experiments have been conducted, including: spent fuel loading, getting back, spent fuel canister hoisting, storage well cover hoisting, storage canister drop and so on. In the study process, the test facility has been set up to carry on the operation and the experiment verification to ensure the reliability and safety of the spent fuel storage system. Spent fuel storage system undertakes spent fuel receiving, spent fuel canister transfer, storage, lifting and other functions in HTR-PM, the project research need to solve several major technical problems related to the spent fuel operation, which mainly include: Develop the transportable spent fuel canister for HTR-PM, the canister is corrosion resistance, impact resistance, and is in subcritical condition when loaded with fuel. Develop the spent fuel canister hoister, which could hoist the spent fuel canister safely and reliably. Develop the spent fuel storage well cover hoister, which could hoist the well cover safely and reliably. Study the small probability of the spent fuel canister in extreme condition of canister hoist falling accidents, to ensure the radiation protect safety and residual heat removal safety of the canister in case of the canister drop when lifting. Develop the spent fuel charging device and return device, which could load the spent fuel elements into the spent fuel canister, and could take out the fuel elements from the canister. The key technology and equipment of the spent fuel storage system in HTR-PM would be solved through the research of the project. Project research is very important for the implementation and safe operation of the HTR-PM project. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2011

High Power Testing of RF Cavities for the PEP II B Factory

We describe the process of conditioning and high-power testing of RF cavities for PEP-II. Procedures for vacuum assembly, bakeout and automated processing are described. Interlocks and safety precautions for protection of equipment and personnel are discussed and performance data of tested cavity assemblies are reported. Performance of ancillary components such as windows, couplers and tuners is also discussed. Comments are included on handling, alignment, installation and commissioning issues where appropriate.

43 PARTICLE ACCELERATORS↗
DOE OSTI2015

Percutaneous Endovascular Salvage Techniques for Implanted Venous Access Device Dysfunction

PurposeImplanted venous access devices (IVADs) are often used in patients who require long-term intravenous drug administration. The most common causes of device dysfunction include occlusion by fibrin sheath and/or catheter adherence to the vessel wall. We present percutaneous endovascular salvage techniques to restore function in occluded catheters. The aim of this study was to evaluate the feasibility, safety, and efficacy of these techniques.Methods and MaterialsThrough a femoral or brachial venous access, a snare is used to remove fibrin sheath around the IVAD catheter tip. If device dysfunction is caused by catheter adherences to the vessel wall, a new “mechanical adhesiolysis” maneuver was performed. IVAD salvage procedures performed between 2005 and 2013 were analyzed. Data included clinical background, catheter tip position, success rate, recurrence, and rate of complication.ResultsEighty-eight salvage procedures were performed in 80 patients, mostly women (52.5 %), with a mean age of 54 years. Only a minority (17.5 %) of evaluated catheters were located at an optimal position (i.e., cavoatrial junction ±1 cm). Mechanical adhesiolysis or other additional maneuvers were used in 21 cases (24 %). Overall technical success rate was 93.2 %. Malposition and/or vessel wall adherences were the main cause of technical failure. No complications were noted.ConclusionThese IVAD salvage techniques are safe and efficient. When a catheter is adherent to the vessel wall, mechanical adhesiolysis maneuvers allow catheter mobilization and a greater success rate with no additional risk. In patients who still require long-term use of their IVAD, these procedures can be performed safely to avoid catheter replacement.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Proposal of an Arc Detection Technique Based on RF Measurements for the ITER ICRF Antenna

RF arc detection is a key operational and safety issue for the ICRF system on ITER. Indeed the high voltages inside the antenna put it at risk of arcing, which could cause substantial damage. This paper describes the various possibilities explored by circuit simulation and the strategy now considered to protect the ITER ICRF antenna from RF arcs.

43 PARTICLE ACCELERATORS↗
DOE OSTI2014

SU-E-T-570: Management of Radiation Oncology Patients with Cochlear Implant and Other Bionic Devices in the Brain and Head and Neck Regions

Purpose: To investigate the current status of clinical usage of cochlear implant (CI) and other bionic devices (BD) in the brain and head and neck regions (BH and N) and their management in patients during radiotherapy to ensure patient health and safety as well as optimum radiation delivery. Methods: Literature review was performed with both CIs and radiotherapy and their variants as keywords in PubMed, INSPEC and other sources. The focus was on CIs during radiotherapy, but it also included other BDs in BHȦN, such as auditory brainstem implant, bionic retinal implant, and hearing aids, among others. Results: Interactions between CIs and radiation may cause CIs malfunction. The presence of CIs may also cause suboptimum dose distribution if a treatment plan was not well designed. A few studies were performed for the hearing functions of CIs under irradiations of 4 MV and 6 MV x-rays. However, x-rays with higher energies (10 to 18 MV) broadly used in radiotherapy have not been explored. These higher energetic beams are more damaging to electronics due to strong penetrating power and also due to neutrons generated in the treatment process. Modern CIs are designed with more and more complicated integrated circuits, which may be more susceptible to radiation damage and malfunction. Therefore, careful management is important for safety and treatment outcomes. Conclusion: Although AAPM TG-34, TG-63, and TG-203 (update of TG-34, not published yet) reports may be referenced for management of CIs and other BDs in the brain and H and N regions, a site- and device-specified guideline should be developed for CIs and other BDs. Additional evaluation of CI functions under clinically relevant set-ups should also be performed to provide clinicians with better knowledge in clinical decision making.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2016

Conceptual design of front ends for the advanced photon source multi-bend achromats upgrade

The proposed Advanced Photon Source (APS) upgrade from a double-bend achromats (DBA) to multi-bend achromats (MBA) lattice with ring energy change from 7 GeV to 6 GeV and beam current from 100 mA to 200 mA poses new challenges for front ends. All front ends must be upgraded to fulfill the following requirements: 1) handle the high heat load from two insertion devices in either inline or canted configuration, 2) include a clearing magnet in the front end to deflect and dump any electrons in case the electrons escape from the storage ring during swap-out injection with the safety shutters open, 3) incorporate the next generation x-ray beam position monitors (XBPMs) into the front end to meet the new stringent beam stability requirements. This paper presents the evaluation of the existing APS front ends and standardizes the insertion device (ID) front ends into two types: one for the single beam and one for the canted beams. The conceptual design of high heat load front end (HHLFE) and canted undulator front end (CUFE) for APS MBA upgrade is presented.

43 PARTICLE ACCELERATORS↗
DOE OSTI2023

Halide Perovskites and Their Derivatives for Efficient, High‐Resolution Direct Radiation Detection: Design Strategies and Applications

Abstract The past decade has witnessed a rapid rise in the performance of optoelectronic devices based on lead‐halide perovskites (LHPs). The large mobility‐lifetime products and defect tolerance of these materials, essential for optoelectronics, also make them well‐suited for radiation detectors, especially given the heavy elements present, which is essential for strong X‐ray and γ‐ray attenuation. Over the past decade, LHP thick films, wafers, and single crystals have given rise to direct radiation detectors that have outperformed incumbent technologies in terms of sensitivity (reported values up to 3.5 × 10 6 µC Gy air −1 cm −2 ), limit of detection (directly measured values down to 1.5 nGy air s −1 ), along with competitive energy and imaging resolution at room temperature. At the same time, lead‐free perovskite‐inspired materials (e.g., methylammonium bismuth iodide), which have underperformed in solar cells, have recently matched and, in some areas (e.g., in polarization stability), surpassed the performance of LHP detectors. These advances open up opportunities to achieve devices for safer medical imaging, as well as more effective non‐invasive analysis for security, nuclear safety, or product inspection applications. Herein, the principles behind the rapid rises in performance of LHP and perovskite‐inspired material detectors, and how their properties and performance link with critical applications in non‐invasive diagnostics are discussed. The key strategies to engineer the performance of these materials, and the important challenges to overcome to commercialize these new technologies are also discussed.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Kinetics Tuning the Electrochemistry of Lithium Dendrites Formation in Lithium Batteries through Electrolytes

Lithium batteries are one of the most advance energy storage devices in the world and have attracted extensive research interests. However, lithium dendrite growth was a safety issue which handicapped the application of pure lithium metal in the negative electrode. In this paper, two solvents, propylene carbonate (PC) and 2-methyl-tetrahydrofuran (2MeTHF), and four Li + salts, LiPF 6 , LiAsF 6 , LiBF 4 and LiClO 4 were investigated in terms of their effects on the kinetics of lithium dendrite formation in eight electrolyte solutions. The kinetic parameters of charge transfer step (exchange current density, j 0 , transfer coefficient, α) of Li + /Li redox system, the mass transfer parameters of Li + (transfer number of Li + , t Li+ , diffusion coefficient of Li + , D Li+ ), and the conductivity (κ) of each electrolyte were studied separately. The results demonstrate that the solvents play a critical role in the measured j 0 , t Li+ , D Li+ , and κ of the electrolyte, while the choice of Li + salts only slightly affect the measured parameters. Finally, the understanding of the kinetics will gain insight into the mechanism of lithium dendrite formation and provide guidelines to the future application of lithium metal.

2-methyl-tetrahydrofuran↗
DOE OSTI2014

New superconducting toroidal magnet system for IAXO, the international AXion observatory

Axions are hypothetical particles that were postulated to solve one of the puzzles arising in the standard model of particle physics, namely the strong CP (Charge conjugation and Parity) problem. The new International AXion Observatory (IAXO) will incorporate the most promising solar axions detector to date, which is designed to enhance the sensitivity to the axion-photon coupling by one order of magnitude beyond the limits of the current state-of-the-art detector, the CERN Axion Solar Telescope (CAST). The IAXO detector relies on a high-magnetic field distributed over a very large volume to convert solar axions into X-ray photons. Inspired by the successful realization of the ATLAS barrel and end-cap toroids, a very large superconducting toroid is currently designed at CERN to provide the required magnetic field. This toroid will comprise eight, one meter wide and twenty one meter long, racetrack coils. The system is sized 5.2 m in diameter and 25 m in length. Its peak magnetic field is 5.4 T with a stored energy of 500 MJ. The magnetic field optimization process to arrive at maximum detector yield is described. In addition, materials selection and their structure and sizing has been determined by force and stress calculations. Thermal loads are estimated to size the necessary cryogenic power and the concept of a forced flow supercritical helium based cryogenic system is given. A quench simulation confirmed the quench protection scheme.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2025

Low Activity Tritium Detection in CCDs Using Deep Learning Techniques

Here, this study explores the use of charge-coupled devices (CCDs) for detecting low-energy beta particles from tritium decay - a critical signal for nuclear safety, nuclear nonproliferation, and environmental monitoring. We employ a dual approach utilizing both measured CCD data and detailed Geant4 simulations. Our analysis compares classical techniques with advanced deep learning methods, including convolutional neural networks (CNNs), autoencoders trained exclusively on tritium data, and preliminary studies on boosted decision trees (BDTs). The CNN, trained on mixed signal/background datasets, demonstrates superior classification performance, while the autoencoder shows the potential of unsupervised, background-agnostic strategies when background characteristics are poorly defined. These results highlight the excellent sensitivity achievable thanks to the background rejection made possible by information-rich CCD data, paving the way for improved portable tritium monitoring.

Autoencoder↗
DOE OSTI2015

Nominal Device Support for ATCA Shelf Manager

The ATCA standard specifies a mandatory Shelf Manager (ShM) unit which is a key element for the system operation. It includes the Intelligent Platform Management Controller (IPMC) which monitors the system health, retrieves inventory information and controls the Field Replaceable Units (FRUs). These elements enable the intelligent health monitoring, providing high-availability and safety operation, ensuring the correct system operation. For critical systems like ones of tokamak ITER these features are mandatory to support the long pulse operation. The Nominal Device Support (NDS) was designed and developed for the ITER CODAC Core System (CCS), which will be the responsible for plant Instrumentation and Control (I and C), supervising and monitoring on ITER. It generalizes the Enhanced Physics and Industrial Control System (EPICS) device support interface for Data Acquisition (DAQ) and timing devices. However the support for health management features and ATCA ShM are not yet provided. This paper presents the implementation and test of a NDS for the ATCA ShM, using the ITER Fast Plant System Controller (FPSC) prototype environment. This prototype is fully compatible with the ITER CCS and uses the EPICS Channel Access (CA) protocol as the interface with the Plant Operation Network (PON). The implemented solution running in an EPICS Input / Output Controller (IOC) provides Process Variables (PV) to the PON network with the system information. These PVs can be used for control and monitoring by all CA clients, such as EPICS user interface clients and alarm systems. The results are presented, demonstrating the fully integration and the usability of this solution. (authors)

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2012

Radiation protection for high energy implantation of light ions in a production environment

In recent years the irradiation of semiconductor devices by light ions with high energies has increasingly become a well-established method to adjust charge carrier lifetimes in semiconductor devices. To introduce this process into the end of frontend production environment several measures in terms of radiation safety will have to be obeyed. An overview on thresholds for particles induced gamma emission will be given, starting with the {sup 11}B(p,{gamma}){sup 12}C reaction at 163keV. The environment has to be shielded from gamma rays, therefore those implanters have to be situated in adequate enclosures. Calculations for specific implant energies are done to define the thicknesses of tool enclosures. A set of radiation detectors monitors the values at well-defined positions online and radiation values are fed into a superordinate system that is directly coupled to the main power supply of the implanter.

36 MATERIALS SCIENCE↗