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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 361 records · Page 20
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

The tundra phenology database: more than two decades of tundra phenology responses to climate change

Observations of changes in phenology have provided some of the strongest signals of the effects of climate change on terrestrial ecosystems. The International Tundra Experiment (ITEX), initiated in the early 1990s, established a common protocol to measure plant phenology in tundra study areas across the globe. Today, this valuable collection of phenology measurements depicts the responses of plants at the colder extremes of our planet to experimental and ambient changes in temperature over the past decades. The database contains 150 434 phenology observations of 278 plant species taken at 28 study areas for periods of 1–26 years. Here we describe the full data set to increase the visibility and use of these data in global analyses and to invite phenology data contributions from underrepresented tundra locations. Portions of this tundra phenology database have been used in three recent syntheses, some data sets are expanded, others are from entirely new study areas, and the entirety of these data are now available at the Polar Data Catalogue (https://doi.org/10.21963/13215).

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

Chemical durability and degradation mechanisms of HT9 based alloy waste forms with variable Zr content

In Corrosion studies were undertaken on alloy waste forms that can result from advanced electrometallurgical processing techniques to better classify their durability and degradation mechanisms. The waste forms were based on the RAW3-(URe) composition, consisting primarily of HT9 steel and other elemental additions to simulate nuclear fuel reprocessing byproducts. The solution conditions of the corrosion studies were taken from an electrochemical testing protocol, and meant to simulate conditions in a repository. The alloys durability was examined in alkaline and acidic brines.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

High Air-Flow Aerosol Filtration Testing

Pressure losses and aerosol collection efficiencies were measured for fibrous filter materials at air-flow rates consistent with high efficiency filtration (hundreds of cubic feet per minute). Microfiber filters coated with nanofibers were purchased and fabricated into test assemblies for a 12-inch duct system designed to mimic high efficiency filtration testing of commercial and industrial processes. Standards and specifications for high efficiency filtration were studied from a variety of institutions to assess protocols for design, testing, operations and maintenance, and quality assurance (e.g., DOE, ASHRAE, ASME). Three materials with varying Minimum Efficiency Reporting Values (MERV) were challenged with sodium chloride aerosol. Substantial filter loading was observed where aerosol collection efficiencies and pressure losses increased during experiments. Filter designs will be optimized and characterized in subsequent years of this study. Additional testing will be performed with higher hazard aerosols at Oak Ridge National Laboratory.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2022

Serum Neutralizing and Enhancing Effects on African Swine Fever Virus Infectivity in Adherent Pig PBMC

African swine fever virus (ASFV) causes hemorrhagic fever with mortality rates of up to 100% in domestic pigs. Currently, there are no commercial vaccines for the disease. Only some live-attenuated viruses have been able to protect pigs from ASFV infection. The immune mechanisms involved in the protection are unclear. Immune sera can neutralize ASFV but incompletely. The mechanisms involved are not fully understood. Currently, there is no standardized protocol for ASFV neutralization assays. In this study, a flow cytometry-based ASFV neutralization assay was developed and tested in pig adherent PBMC using a virulent ASFV containing a fluorescent protein gene as a substrate for neutralization. As with previous studies, the percentage of infected macrophages was approximately five time higher than that of infected monocytes, and nearly all infected cells displayed no staining with anti-CD16 antibodies. Sera from naïve pigs and pigs immunized with a live-attenuated ASFV and fully protected against parental virus were used in the assay. The sera displayed incomplete neutralization with MOI-dependent neutralizing efficacies. Extracellular, but not intracellular, virions suspended in naïve serum were more infectious than those in the culture medium, as reported for some enveloped viruses, suggesting a novel mechanism of ASFV infection in macrophages. Both the intracellular and extracellular virions could not be completely neutralized.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2012

Portals 4 network API definition and performance measurement

Portals is a low-level network programming interface for distributed memory massively parallel computing systems designed by Sandia, UNM, and Intel. Portals has been designed to provide high message rates and to provide the flexibility to support a variety of higher-level communication paradigms. This project developed and analyzed an implementation of Portals using shared memory in order to measure and understand the impact of using general-purpose compute cores to handle network protocol processing functions. The goal of this study was to evaluate an approach to high-performance networking software design and hardware support that would enable important DOE modeling and simulation applications to perform well and to provide valuable input to Intel so they can make informed decisions about future network software and hardware products that impact DOE applications.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2012

THE ABSORPTION OF HYDROGEN ON LOW PRESSURE HYDRIDE MATERIALS

For this study, hydrogen getter materials (Zircaloy-4 and pure zirconium) that have a high affinity for hydrogen (and low overpressure) have been investigated to determine the hydrogen equilibrium pressure on Zircaloy-4 and pure zirconium. These materials, as with most getter materials, offered significant challenges to overcome given the low hydrogen equilibrium pressure for the temperature range of interest. Hydrogen-zirconium data exists for pure zirconium at 500 C and the corresponding hydrogen overpressure is roughly 0.01 torr. This manuscript presents the results of the equilibrium pressures for the absorption and desorption of hydrogen on zirconium materials at temperatures ranging from 400 C to 600 C. The equilibrium pressures in this temperature region range from 150 mtorr at 600 C to less than 0.1 mtorr at 400 C. It has been shown that the Zircaloy-4 and zirconium samples are extremely prone to surface oxidation prior to and during heating. This oxidation precludes the hydrogen uptake, and therefore samples must be heated under a minimum vacuum of 5 x 10{sup -6} torr. In addition, the Zircaloy-4 samples should be heated at a sufficiently low rate to maintain the system pressure below 0.5 mtorr since an increase in pressure above 0.5 mtorr could possibly hinder the H{sub 2} absorption kinetics due to surface contamination. The results of this study and the details of the testing protocol will be discussed.

08 HYDROGEN↗
DOE OSTI2021

Cell-Type-Specific Proteomics Analysis of a Small Number of Plant Cells by Integrating Laser Capture Microdissection with a Nanodroplet Sample Processing Platform

Plant organs and tissues contain multiple cell types, which are well organized in 3-dimensional structure to efficiently perform physiological functions such as homeostasis, response to environmental perturbation, pathogen infection. It is critically important to perform molecular measurements at the cell-type-specific level to discover mechanisms and unique features of cell populations that govern differentiation and respond to external perturbations. Although mass spectrometry-based proteomics has been demonstrated as an enabling discovery tool to study plant physiology, conventional approaches require millions of cells to generate robust biological conclusions. Such requirements mask the cell-to-cell heterogeneities and limit the comprehensive profiling of plant proteins at spatially resolved and cell-type-specific resolutions. This protocol describes a recently-developed proteomics workflow for studying a small number of plant cells by integrating laser capture microdissection, microfluidic nanodroplet-based sample preparation, with ultrasensitive liquid chromatography-mass spectrometry. Using poplar as a model tree species, we provide detailed protocols, including plant tissue harvest, tissue preparation, cryosectioning, laser microdissection, protein digestion, mass spectrometry measurement, and data analysis. We show the workflow enables the precise identification and quantification of thousands of proteins from hundreds of isolated plant root and leaf cells.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2019

A New Protocol for Efficient and High Yield Preparation of Nanocellulose from Elaeis guineensis Biomass: A Response Surface Methodology (RSM) Study

An innovative system for isolating nanocellulose was established that uses Ni(NO{sub 3}){sub 2} transition metal salt without the assistance of mechanical disintegrations or mineral acid and was compared with the classic production by tedious acid hydrolysis. Optimization study on Ni(II)-catalyzed hydrolysis of cellulose isolated from oil palm (Elaeis guineensis) empty fruit bunch (OPEFB) towards nanocellulose yield was investigated. Response surface methodology-central composite design was used to design and optimize the experiments with three operating parameters: pH of Ni(NO{sub 3}){sub 2} (pH 2–4), reaction time (20‒100 min) and reaction temperature (25‒65 °C). The present study indicated that the nanocellulose yield as high as 81.37% was achieved under hydrolysis conditions of pH 3, 58 °C within 58 min. At the optimum conditions, the OPEFB derived nanocellulose rendered high crystallinity of 91.1% and excellent thermal stability of 341 °C. Evidence of the successful isolation of nanocellulose was proven by HRTEM observation revealing fibrils formed the long and interconnected network-like structure with the average width of 41.1 ± 1.6 nm and several micrometers in length, which resulted in high aspect ratio. Thus, the obtained nanocellulose via Ni(II)-catalyzed hydrolysis has numerous potential applications and represent a green alternative for the treatment of OPEFB. This study provided a facile high yield procedure for the production of nanocellulose with similar characteristics to traditional nanocellulose, which was significant to the commercialization of nanocellulose.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2014

Enhancing robustness of multiparty quantum correlations using weak measurement

Multipartite quantum correlations are important resources for the development of quantum information and computation protocols. However, the resourcefulness of multipartite quantum correlations in practical settings is limited by its fragility under decoherence due to environmental interactions. Though there exist protocols to protect bipartite entanglement under decoherence, the implementation of such protocols for multipartite quantum correlations has not been sufficiently explored. Here, we study the effect of local amplitude damping channel on the generalized Greenberger–Horne–Zeilinger state, and use a protocol of optimal reversal quantum weak measurement to protect the multipartite quantum correlations. We observe that the weak measurement reversal protocol enhances the robustness of multipartite quantum correlations. Further it increases the critical damping value that corresponds to entanglement sudden death. To emphasize the efficacy of the technique in protection of multipartite quantum correlation, we investigate two proximately related quantum communication tasks, namely, quantum teleportation in a one sender, many receivers setting and multiparty quantum information splitting, through a local amplitude damping channel. We observe an increase in the average fidelity of both the quantum communication tasks under the weak measurement reversal protocol. The method may prove beneficial, for combating external interactions, in other quantum information tasks using multipartite resources. - Highlights: • Extension of weak measurement reversal scheme to protect multiparty quantum correlations. • Protection of multiparty quantum correlation under local amplitude damping noise. • Enhanced fidelity of quantum teleportation in one sender and many receivers setting. • Enhanced fidelity of quantum information splitting protocol.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2024

Countering Weapons of Mass Destruction Office (CWMD) Data Categorization Study: Chemical, Biological, Radiological, and Nuclear (CBRN) Detection Device Data

Pacific Northwest National Laboratory (PNNL) seeks to address critical questions related to chemical, biological, radiological, and nuclear (CBRN) detection devices. This research aims to enhance the security and understanding of these devices by investigating various aspects of their identification, communication, and functionality. The primary focus is on network security, malware detection, device identification, and intelligence gathering. CBRN data can be categorized in various ways depending on the purpose of CBRN detection devices and the specific context of the applications for analysis. Criteria that can be used to assist in this effort include but are not limited to data type, data protocol, source/destination, application, time, security, and content. This study will inform additional paths for data classification, data profiling, data mapping, and data modeling. This will help the Countering Weapons of Mass Destruction Office (CWMD) better understand their data and make informed decisions based on the insights gained from this study and their application. The CBRN Data Categorization study will include the identification of 5–10 different CBRN detection devices with unique characteristics for assessing and analyzing the data that is being produced by and transmitted from these devices.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2025

PV backsheets survey protocol: A framework for geo-spatial field surveys for bulk material characterization and reliability analysis applied across 41 PV systems

As widespread adoption of photovoltaic (PV) technologies continues, understanding the lifetime of modules is paramount to the viability of the industry as an environmentally conscious alternative to traditional energy generation. Although power degradation can affect the total energy production of a module over its lifetime, module safety failures necessitate the removal of a module leading to a loss of not only the particular asset, but the earning potential of the device. Therefore, it is critical to ensure that the components that provide essential safety functions for PV module operate for their entire rated lifetime. PV backsheets provide necessary electrical insulation to the completed device and failure of this component is cause for a immediate removal of the module. Degradation of the PV module backsheet has led to module safety failures in large-scale installations, costing millions of dollars in damages and lost potential revenue. The spatio-temporal degradation of fielded PV modules is important to study in order to identify which modules within installations are experiencing the greatest exposure conditions and in turn have the highest chance of failure. This paper describes a comprehensive field survey protocol developed for monitoring PV module backsheet performance using solely non-destructive methods in commercial PV fields. The protocol establishes a field naming convention, sampling method, data handling requirements, and measurement procedures. By ensuring consistent data collection practices, the field survey protocol enables research groups to obtain data of uniform quality on backsheet performance over multiple years and locations. In this study, the developed protocol was implemented at forty-one PV sites. Eight different types of airside layer backsheet materials including poly(vinylidene fluoride) (PVDF), acrylic PVDF, poly(tetrafluoroethylene-co-hexafluoropropylene-co-vinylidene fluoride) (THV), poly(vinyl fluoride) (PVF), poly(ethylene terephthalate) (PET), fluoroethylene vinyl ether (FEVE), polyethylene naphthalate (PEN), and glass were identified using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. The field survey results show that the spatial distribution of degradation indicators are non-uniform within a particular module, individual site, and across site locations. The degradation of PV modules increased in severity for modules mounted at the edge of rows (across a field) and near the junction box (within a module). This study demonstrates the sensitivity of material performance to exposure length across different materials and climates.

14 SOLAR ENERGY↗
DOE OSTI2017

Highlighting the complexities of a groundwater pilot study during an avian influenza outbreak: Methods, lessons learned, and select contaminant results

The highly pathogenic avian influenza (H5N2) outbreak in the Midwestern United States (US) in 2015 was historic due to the number of birds and poultry operations impacted and the corresponding economic loss to the poultry industry and was the largest animal health emergency in US history. The U.S. Geological Survey (USGS), with the assistance of several state and federal agencies, aided the response to the outbreak by developing a study to determine the extent of virus transport in the environment. The study goals were to: develop the appropriate sampling methods and protocols for measuring avian influenza virus (AIV) in groundwater, provide the first baseline data on AIV and outbreak- and poultry-related contaminant occurrence and movement into groundwater, and document climatological factors that may have affected both survival and transport of AIV to groundwater during the months of the 2015 outbreak. While site selection was expedient, there were often delays in sample response times due to both relationship building between agencies, groups, and producers and logistical time constraints. This study's design and sampling process highlights the unpredictable nature of disease outbreaks and the corresponding difficulty in environmental sampling of such events. The lessons learned, including field protocols and approaches, can be used to improve future research on AIV in the environment. - Highlights: • Historic 2015 avian influenza outbreak resulted in over 50 million birds destroyed. • Study to determine environmental extent of virus transport logistically challenging. • Challenges included communication, relationship building, and safety protocols. • Temperature, precipitation may have favored virus survival, transport to subsurface.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Estimating the randomness of quantum circuit ensembles up to 50 qubits

Random quantum circuits have been utilized in the contexts of quantum supremacy demonstrations, variational quantum algorithms for chemistry and machine learning, and blackhole information. The ability of random circuits to approximate any random unitaries has consequences on their complexity, expressibility, and trainability. To study this property of random circuits, we develop numerical protocols for estimating the frame potential, the distance between a given ensemble and the exact randomness. Our tensor-network-based algorithm has polynomial complexity for shallow circuits and is high-performing using CPU and GPU parallelism. We study 1. local and parallel random circuits to verify the linear growth in complexity as stated by the Brown–Susskind conjecture, and; 2. hardware-efficient ansätze to shed light on its expressibility and the barren plateau problem in the context of variational algorithms. Our work shows that large-scale tensor network simulations could provide important hints toward open problems in quantum information science.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2019

Saturated random packing built of arbitrary polygons under random sequential adsorption protocol

Random packings and their properties are a popular and active field of research. Numerical algorithms that can efficiently generate them are useful tools in their study. This paper focuses on random packings produced according to the random sequential adsorption (RSA) protocol. Developing the idea presented by G. Zhang, where saturated random packings built of regular polygons were studied, we create an algorithm that generates strictly saturated packings built of any polygons. Then, the algorithm was used to determine the packing fractions for arbitrary triangles. In this work, the highest mean packing density, 0.552 814 ± 0.000 063, was observed for triangles of side lengths 0.63 : 1 : 1. Additionally, microstructural properties of such packings, kinetics of their growth, as well as distributions of saturated packing fractions and the number of RSA iterations needed to reach saturation were analyzed.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2025

Crystal structure and polymorphic forms of auranofin revisited

Auranofin, initially developed as a treatment for rheumatoid arthritis, is currently under extensive investigation as a potential drug for various conditions, including cancer, bacterial infections, and parasitic infections. The compound is a known inhibitor of thioredoxin reductase (TXNRD1) and related selenoproteins. Although preliminary studies on the auranofin crystal polymorphism exist, and a low-quality crystal structure has been reported, a comprehensive crystallographic characterization remains unexplored. Utilizing X-ray crystallography techniques, we conducted detailed structural analysis of auranofin and compared our findings with related organogold compounds. Implementation of Hirshfeld atom refinement (HAR) enabled a more accurate hydrogen atom positioning in the structure. The crystal packing reveals a layered arrangement stabilised by numerous weak hydrogen bonds and dispersive interactions. Notably, our attempts to reproduce the previously reported polymorphic form of auranofin, purportedly more water-soluble, were unsuccessful despite following published protocols. To our knowledge, this is the first study describing a “disappearing polymorph” phenomenon of any pharmaceutically relevant transition metal coordination compound. Our findings may have significant implications for medicinal chemistry and pharmacology of coordination complexes, suggesting the need for systematic revision of historical crystallographic data in this field.

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

Sparse Phase Ansatzes for Resource-Efficient Qudit State Preparation via the SNAP-Displacement Protocol

Efficient preparation of nonclassical bosonic states is a central requirement for quantum computing, simulation, and precision metrology. We study resource-efficient quantum state preparation in bosonic qudit systems using the SNAP-displacement (SD) protocol. Existing SD-based approaches typically require a large number of gates and SNAP phases, resulting in complex control pulses with longer ansatz durations and amplified impact of photon-loss and control errors. In this work, we focus on the near- to medium-term regime, in which noisy quantum devices impose trade-offs on the fidelity that can be achieved, which must be taken into account. Specifically, we propose to optimize only a subset of the SNAP phases and introduce three progressively more general sparse ansatzes. To provide fine-grained control and identify the most suitable ansatz for a given target fidelity, we further employ a scalarized multi-objective optimization that trades off fidelity against either the number of phases or the duration of the ansatz. Numerical results for several target states and qudit dimensions up to $d=64$, evaluated through the hypervolume of the Pareto frontiers, show that these sparse ansatzes achieve favorable trade-offs over the fully parameterized SD protocol in both ideal and noisy settings. The advantage is strongest and most consistent when minimizing the number of phases, while improvements in ansatz duration are smaller and more dependent on the target-state family and noise level, suggesting a practical route to more efficient near- and medium-term bosonic state preparation.

Ferrari Dacrema, Maurizio [Milan Polytechnic] (ORC↗
DOE OSTI2011

Dosimetry protocol for the preclinical trials in white-beam minibeam radiation therapy

Purpose: In the quest of a curative radiotherapy treatment for gliomas, new delivery modes are being explored. At the Biomedical Beamline of the European Synchrotron Radiation Facility, a new spatially fractionated technique, called minibeam radiation therapy (MBRT), is under development. The aims of this work were to assess different dosimetric aspects and to establish a dosimetry protocol to be applied in the forthcoming animal (rat) studies in order to evaluate the therapeutic index of this new radiotherapy approach. Methods: Absolute dosimetry was performed with a thimble ionization chamber (PTW semiflex 31010) whose center was positioned at 2 g cm{sup -2} depth. To translate the dose measured in broad beam configuration to the dose deposited with a minibeam, the scatter factors were used. Those were assessed by using the Monte Carlo simulations and verified experimentally with Gafchromic films and a Bragg Peak chamber. The comparison of the theoretical and experimental data were used to benchmark the calculations. Finally, the dose distributions in a rat phantom were evaluated by using the validated Monte Carlo calculations. Results: The absolute dosimetry in broad beam configuration was measured in reference conditions. The dose rate was in the range between 168 and 224 Gy/min, depending on the storage ring current. A scatter factor of 0.80 {+-} 0.04 was obtained. Percentage depth dose and lateral profiles were evaluated both in homogenous and heterogeneous slab phantoms. The general good agreement between Monte Carlo simulations and experimental data permitted the benchmark of the calculations. Finally, the peak doses in the rat head phantom were assessed from the measurements in reference conditions. In addition, the peak-to-valley dose ratio values as a function of depth in the rat head were evaluated. Conclusions: A new promising radiotherapy approach is being explored at the ESRF: Minibeam Radiation Therapy. To assess the therapeutic index of this new modality, in vivo experiments are being planned, for which an accurate knowledge of the dosimetry is essential. For that purpose, a complete set of measurements and Monte Carlo simulations was performed. The first dosimetry protocol for preclinical trials in minibeam radiation therapy was established. This protocol allows to have reproducibility in terms of dose for the different biological studies.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2015

Channel-capacity gain in entanglement-assisted communication protocols based exclusively on linear optics, single-photon inputs, and coincidence photon counting

Entanglement can effectively increase communication channel capacity as evidenced by dense coding that predicts a capacity gain of 1 bit when compared to entanglement-free protocols. However, dense coding relies on Bell states and when implemented using photons the capacity gain is bounded by 0.585 bits due to one's inability to discriminate between the four optically encoded Bell states. In this research we study the following question: Are there alternative entanglement-assisted protocols that rely only on linear optics, coincidence photon counting, and separable single-photon input states and at the same time provide a greater capacity gain than 0.585 bits? In this study, we show that besides the Bell states there is a class of bipartite four-mode two-photon entangled states that facilitate an increase in channel capacity. We also discuss how the proposed scheme can be generalized to the case of two-photon N-mode entangled states for N=6,8.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗