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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 253 records · Page 14
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Immunomodulation by cannabidiol in bovine primary ruminal epithelial cells

Ruminant livestock experience a number of challenges, including high concentrate diets, weaning and transport, which can increase their risk of disorders such as ruminal acidosis, and the associated inflammation of the ruminal epithelium. Cannabidiol (CBD), a phytochemical from hemp (Cannabis sativa), is a promising target as a therapy for gastrointestinal inflammation, and may be extremely valuable as either a treatment or prophylactic. However, the effects of CBD in the the ruminant gastrointestinal tract have not been explored, in part due to the restrictions on feeding hemp to livestock. Therefore, the objective of this study was to investigate the immunomodulatory properties of CBD using a model of inflammation in primary ruminal epithelial cells (REC). In addition, CBD dose was evaluated for possible cytotoxic effects. Negative effects on cell viability were not observed when REC were exposed to 10 μM CBD. However, when the dose was increased to 50 μM for 24 h, there was a significant cytotoxic effect. When 10 μM CBD was added to culture media as treatment for inflammation induced with lipopolysaccharide (LPS), expression of genes encoding for pro-inflammatory cytokine IL1B was less compared to LPS exposure alone, and CBD resulted in a down-regulation of IL6. As a pre-treatment, prior to LPS exposure, REC had decreased expression of IL6 and CXCL10 while CBD was present in the media, but not when it was removed prior to addition of LPS. Results suggest that CBD may reduce cytokine transcription both during LPS-induced inflammation and when used preventatively, although these effects were dependent on its continued presence in the culture media. Overall, these experiments provide evidence of an immunomodulatory effect by CBD during a pro-inflammatory response in primary REC in culture.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Analysis of Respirator Cartridge Performance Testing on the 702-AZ Primary Exhauster for the Hanford AY/AZ Tank Farms during a Waste-Disturbing Event

Washington River Protection Solutions (WRPS) conducted tests using two types of chemical cartridges for use in air-purifying respirators (APR) to determine the period of time that the cartridges would provide adequate performance1 for APRs used to protect workers when exposed to a mixture of Chemicals of Potential Concern (COPC) from vapors exiting the 702-AZ Primary Exhauster for the Hanford AY-AZ tank farms. Unlike prior cartridge testing on the 702-AZ Primary Exhauster, the recent tests were performed during a waste-disturbing event. The Occupational Safety and Health Administration (OSHA) identifies cartridge testing as a valid approach for establishing a cartridge change schedules. Testing is commonly applied in situations where mixtures of COPCs exist, and where other approaches, such as manufacturer recommendations and modeling, are less reliable. The tests were designed and conducted to assure measurement and/or control of the key variables OSHA identified as important to estimate the cartridge service life, including temperature, humidity, COPC concentration, breathing rate, and cartridge adsorption capacity. Testing was conducted from February 10–11, 2017, on a slipstream from the 702-AZ exhauster fed to a respirator cartridge test stand developed by WRPS in collaboration with HiLine Engineering (Richland, Washington). Multipurpose respirator cartridges, SCOTT 7422-SD1 and SCOTT 7422-SC1 (SCOTT Safety, Monroe, North Carolina), were assessed on separate days. Sample media (sorbent tubes) and canisters (e.g., Summa) sampling were used to collect samples of the vapor stream entering and exiting the respirator cartridge and were subsequently analyzed for COPC concentrations. Pacific Northwest National Laboratory was tasked with conducting an independent analysis of the analytical results and making recommendations based on the results for respiratory cartridge performance and service life.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2023

ECAR-6564 MARVEL Project Primary Coolant System ASME BPVC Section III Division 5 Design by Analysis

This report demonstrates that the MARVEL Reactor Primary Coolant Boundary (herein referred to as the Primary Coolant System, or PCS) is designed to meet ASME BPVC Section III Division 5 elevated temperature service design-by-analysis criteria. The analysis approach that delineates division of responsibilities to meet project objectives is discussed herein. In short, Design and Service Level A, B, and C code calculations are detailed in ECAR-6580 for the majority of the PCS with complex geometry, while the Lower Downcomers, Bottom Head, and Reactor Core Barrel are analyzed in ANL-23/56. Service Level D code calculations are detailed in this document.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2024

PV-Finder: ML Based Algorithm for Primary Vertex Identification

he CMS detector at the High-Luminosity Large Hadron Collider (HL-LHC) will operate in challenging conditions with expected pile-up of up to 200 collisions per bunch crossing, necessitating the development of a more resilient primary vertex (PV) reconstruction method to ensure the integrity of data analysis and the efficiency of the CMS triggering system. This contribution describes preliminary studies on a new ML based PV-Finder method for PV identification. The method is based on a model trained using Kernel Density Estimations (KDEs) derived from the positions of reconstructed tracks at the beamline, incorporating uncertainties from track parameters. It also utilizes target histograms, modeled as Gaussian distributions centered on the actual ground truth values of specific primary vertices.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2024

Finding of adverse effect and proposed mitigation for the removal of three primary resources and twenty-four accessory resources within the mercury historic district, area 23, nevada national security site, nye county, nevada

The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO) proposes the removal of three primary resources and 24 accessory resources in Mercury on the Nevada National Security Site (NNSS) in Nye County, Nevada. The majority of the resources are concrete pads that have previously been recorded as either primary resources or accessory resources thereof within the Mercury Historic District (MHD). They represent the former locations of environmental support program buildings including a greenhouse (MHD Resource C312), warehouses (Resource C293), offices (Resource C314), dormitories (Resource C298), and two of unknown purpose (Resource C292). The other resources include a buried storage tank and sidewalks.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Back-Stress and Its Evolution during Primary Creep in Particle Strengthened Nickel Superalloys

According to Eshelby’s theory, inelastically inhomogeneous inclusions in a metallic matrix give rise to a distribution of internal stresses. In the case of particle strengthened materials, such as nickel base superalloys, the presence and evolution of this back-stress leads to various observable effects, such as primary creep, back-flow upon loading, and memory of prior deformation. This article presents the background of the concept of back-stress and how it applies to the scenario of creep. A derivation of an evolution equation for back-stress in the context of primary creep is also presented. The results from neutron diffraction with in-situ creep experiments on directionally solidified nickel superalloys are presented in order to demonstrate the validity of the proposed equation and the corollaries derived therefrom.

36 MATERIALS SCIENCE↗
DOE OSTI2021

An evaluation of prognostic factors, oncologic outcomes, and management for primary and recurrent squamous cell carcinoma of the vulva

Objective: To evaluate prognostic factors, outcomes, and management patterns of patients treated for squamous cell carcinoma of the vulva. Methods: One hundred sixty-four women were retrospectively identified with primary squamous cell carcinoma of the vulva treated at our institution between 1/1996–12/2018. Descriptive statistics were performed on patient, tumor, and treatment characteristics. The χ 2 tests and t-tests were used to compare categorical variables and continuous variables, respectively. Recurrence free survival (RFS), overall survival (OS), and disease-specific survival (DSS) were analyzed with Kaplan-Meier estimates, the log-rank test, and Cox proportional hazards. Results: Median follow-up was 52.5 months. Five-year RFS was 67.9%, 60.0%, 42.1%, and 20.0% for stage I–IV, respectively. Five-year DSS was 86.2%, 81.6%, 65.0%, and 42.9% for stage I–IV, respectively. On multivariate analysis, positive margins predicted overall RFS (hazard ratio [HR]=3.55; 95% confidence interval [CI]=1.18–10.73; p=0.025), while presence of lichen sclerosus on pathology (HR=2.78; 95% CI=1.30–5.91; p=0.008) predicted local RFS. OS was predicted by nodal involvement (HR=2.51; 95% CI=1.02–6.13; p=0.043) and positive margins (HR=5.19; 95% CI=2.03–13.26; p=0.001). Adjuvant radiotherapy significantly improved RFS (p=0.016) and DSS (p=0.012) in node-positive patients. Median survival after treatment of local, groin, and pelvic/distant recurrence was 52, 8, and 5 months, respectively. Conclusion: For primary treatment, more conservative surgical approaches can be considered with escalation of treatment in patients with concurrent precursor lesions, positive margins, and/or nodal involvement. Further studies are warranted to improve risk stratification in order to optimize treatment paradigms for vulvar cancer patients.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2020

Impacts of land use change and elevated CO 2 on the interannual variations and seasonal cycles of gross primary productivity in China

Climate change, rising CO 2 concentration, and landuse and land cover change (LULCC) are primary driving forces for terrestrialgross primary productivity (GPP), but their impacts on the temporal changesin GPP are uncertain. In this study, the effects of the three main factorson the interannual variation (IAV) and seasonal cycle amplitude (SCA) of GPPin China were investigated using 12 terrestrial biosphere models from theMulti-scale Synthesis and Terrestrial Model Intercomparison Project. Thesimulated ensemble mean value of China's GPP between 1981 and 2010, drivenby common climate forcing, LULCC and CO 2 data, was found to be7.4±1.8 Pg C yr -1 . In general, climate was the dominant controlfactor of the annual trends, IAV and seasonality of China's GPP. Theoverall rising CO2 led to enhanced plant photosynthesis, thusincreasing annual mean and IAV of China's total GPP, especially innortheastern and southern China, where vegetation is dense. LULCC decreasedthe IAV of China's total GPP by ~7%, whereas rising CO 2 induced an increase of 8 %. Compared to climate change andelevated CO 2 , LULCC showed less contributions to GPP's temporalvariation, and its impact acted locally, mainly in southwestern China.Furthermore, this study also examined subregional contributions to thetemporal changes in China's total GPP. Southern and southeastern Chinashowed higher contributions to China's annual GPP, whereas southwestern andcentral parts of China explained larger fractions of the IAV in China's GPP.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1970

Discrete control of linear distributed systems with application to the deformable primary mirror of a large orbiting telescope

One of the more significant technological problems associated with the orbital operation of large astronomical telescope's is the fabrication and maintenance of the primary mirror surface to the tolerance required for diffraction-limited performance. An interesting approach to the solution of this problem involves continuously measuring and automatically correcting the optical surface of a thin deformable mirror by means of discrete actuators located on its rear surface: The realization of diffraction-limited performance from a telescope in space by this method rests on the ability of the designer to achieve extremely accurate control of a highly complex, interacting, multivariable system. This paper presents the results of a detailed study of the discrete control of linear distributed systems with specific application to the design of a practical controller for a plant representative of a telescope primary mirror for an orbiting astronomical observatory. The problem of controlling the distributed plant is treated by employing modal techniques to represent variations in the optical figure. Distortion of the mirror surface, which arises primarily from thermal gradients, is countered by actuators working against a backing structure to apply a corrective force distribution to the controlled surface. Each displacement actuator is in series with a spring attached to the mirror by means of a pad intentionally introduced to restrict the excitation of high-order modes. Control is then exerted over a finite number (equal.to the number of actuators) of the most significant modes. Through the application of the modal expansion technique the mirror equation of motion is transformed tb a set of uncoupled, linear, time-invariant, ordinary differential equations. The desired dynamic response and static accuracy may then be achieved by the application of classical single-variable design techniques. The formulation of a quadratic performance index which incorporates a measure of image quality permits determination of the trade-off between the-number of actuators and optical purity. A criterion for defining actuator placement and pad size is presented which minimizes the tendency of the controller to excite the unmonitored modes.

Jeremiah F Creedon↗
NASA NTRS1971

Electron-impact promoted fragmentation of alkyl-n-/1-phenylethyl/-carbamates of primary, secondary and tertiary alcohols.

The mass spectra of twenty alkyl carbamates derived from primary, secondary, and tertiary alcohols are investigated, using deuterium labeling and high-resolution mass spectrometry. Several of the primary and secondary alcohol derivatives are found to yield an ion formally equivalent to the product ion of a McLafferty rearrangement. Deuterium labeling, however, revealed a lack, in these carbamate derivatives, of the usual site specificity associated with the McLafferty rearrangement. A double hydrogen rearrangement process was observed in the mass spectra of several carbamates derived from tertiary alcohols.

Pereira, W. E.↗
NASA NTRS1972

An electron microscopy examination of primary recrystallization in TD-nickel.

Primary recrystallization in TD-nickel 1 in. bar has previously been regarded as the process by which the initial fine grain structure is converted to a coarse grain size (increases in grain size by 500 times) under suitable deformation and annealing conditions. This process is dependent on deformation mode. While it occurs readily after rolling transverse to the bar axis and annealing (800 C), it is completely inhibited by longitudinal rolling and swaging deformations, even for very high (1320 C) annealing temperatures. A transmission electron microscopy examination of deformation and annealing substructures indicates that primary recrystallization in TD-nickel 1 in. bar actually occurs on the sub-light optical level, to produce a grain structure similar in size to the initial fine grained state.

Petrovic, J. J.↗
NASA NTRS1973

Mechanical Attachment of Reusable Surface Insulation to Space Shuttle Primary Structure

Three methods of attaching surface insulation tiles to shuttle primary structure have been proposed: direct bond, mechanical attachment, and subpanels with standoffs. The direct bond approach is lightweight but is difficult to refurbish and inspect. The subpanel approach is heavier but allows for easy refurbishment since subpanels are easily removed and replaced. The mechanical attachment approach allows easy refurbishment and inspection and is lightweight when an efficient insulator is used between surface insulation tiles and primary structure.

Fleck, R. W.↗
NASA NTRS1975

The 100 cm solar telescope primary mirror study

The manufacturing impact of primary mirror configuration on the performance of a 100 cm aperture solar telescope was studied. Three primary mirror configurations were considered: solid, standard lightweight, and mushroom. All of these are of low expansion material. Specifically, the study consisted of evaluating the mirrors with regard to: manufacturing metrology, manufacturing risk factors and ultimate quality assessment. As a result of this evaluation, a performance comparison of the configurations was made, and a recommendation of mirror configuration is the final output. These evaluations, comparisons and recommendations are discussed in detail. Other investigations were completed and are documented in the appendices.

Source record↗
NASA NTRS1975

Measurement of the primary cosmic electron spectrum from 10 to about 250-GeV

The intensity and energy spectrum of primary cosmic electrons from 10 to approximately 250 GeV was studied using balloon-borne detectors. Both of the detectors were large area ionization calorimeters with frequent sampling of showering particles and were capable of energy resolution of approximately 7%. A time-of-flight system and detectors to sample the lateral properties of showers were used to examine and improve background rejection. The results of the balloon flights from Alamogordo, N.M. in 1970 and Cape Girardeau, Missouri in 1972 indicated that the primary cosmic ray electron differential energy spectrum exhibits no change of slope in the energy range measured and is well represented by a power law. These results indicate that the cosmic electron spectrum is steeper than the cosmic ray proton spectrum. It is shown that these data are consistent with the leakage lifetime model for the propagation of cosmic electrons in the Galaxy, although other more complex models cannot be excluded on the basis of these data.

Silverberg, R. F.↗
NASA NTRS1976

Measurement of the primary cosmic electron spectrum from 10 to about 250 GeV

The intensity and energy spectrum of primary cosmic electrons from 10 to about 250 GeV have been studied by using balloon-borne detectors. The detectors were large-area ionization calorimeters which sampled showering particles frequently and demonstrated an energy resolution of about 7% in calibration tests. On one of the flights a time-of-flight system and detectors to sample the lateral properties of showers were used to examine and to test background rejection. The results of the balloon flights from Alamogordo, N. Mex., in 1970 and Cape Girardeau, Mo., in 1972 indicated that the primary cosmic ray electron differential energy spectrum exhibits no change of slope in the energy range measured and is well represented by a power law. The results indicate that the cosmic electron spectrum is steeper than the cosmic ray proton spectrum. It is shown that these data are consistent with the leakage lifetime model for the propagation of cosmic electrons in the galaxy, although other more complex models cannot be excluded on the basis of these data.

Silverberg, R. F.↗
NASA NTRS1977

Viking 75 project: Viking lander system primary mission performance report

Viking Lander hardware performance during launch, interplanetary cruise, Mars orbit insertion, preseparation, separation through landing, and the primary landed mission, with primary emphasis on Lander engineering and science hardware operations, the as-flown mission are described with respect to Lander system performance and anomalies during the various mission phases. The extended mission and predicted Lander performance is discussed along with a summary of Viking goals, mission plans, and description of the Lander, and its subsystem definitions.

Cooley, C. G.↗