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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Analysis of Defense Waste Processing Facility Sample: Recycle Collection Tank Sample Batch 4945

The Savannah River National Laboratory (SRNL) was requested by Savannah River Remediation (now Savannah River Mission Completion (SRMC)), through a Technical Task Request, to characterization the “as-received” Recycle Collection Tank (RCT) Sample identified as sample batch 4945 [Sludge Receipt and Adjustment Tank (SRAT) batch 796)], which was delivered to SRNL Shielded Cells on January 28, 2021. The RCT characterization data will be used as input to the Defense Waste Processing Facility (DWPF) Recycle Diversion Project. This RCT report is the first of three sample characterization reports that will be used for this DWPF Project. The other DWPF reports will involve the characterization of the Off-Gas Condensate Tank (OGCT) and the Slurry Mix Evaporator Condensate Tank (SMECT) samples.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

Analysis of Defense Waste Processing Facility Sample: Off-Gas Condensate Tank Sample Batch 27862

The Savannah River National Laboratory (SRNL) was requested by Savannah River Remediation (now Savannah River Mission Completion (SRMC)), through a Technical Task Request (X-TTR-H-00107), to characterize the “as-received” Off-Gas Condensate Tank (OGCT) Sample identified as sample batch 27862, which was delivered to SRNL Shielded Cells on April 30, 2021. This OGCT report is the third of three sample characterization reports dealing with this Defense Waste Processing Facility (DWPF) Recycle Diversion Project. The other two recycling stream characterization reports are the Recycle Collection Tank (RCT) and the Slurry Mix Evaporator Condensate Tank (SMECT) sample report.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

Analysis of Defense Waste Processing Facility Sample: Slurry Mix Evaporator Condensate Tank Sample Batch 4638

The Savannah River National Laboratory (SRNL) was requested by Savannah River Remediation (SRR, now Savannah River Mission Completion (SRMC)), through a Technical Task Request, to characterization the “as-received” Slurry Mix Evaporator Condensate Tank (SMECT) sample identified as sample batch 4638, which was delivered to SRNL Shielded Cells on March 19, 2021. The SMECT characterization data will be used as input to the Defense Waste Processing Facility (DWPF) Recycle Diversion Project. This SMECT report is the second of three sample characterization reports that will be used for this DWPF Project. The other two DWPF characterization reports involve the characterization of the Recycle Collection Tank (RCT) sample and the future Off-Gas Condensate Tank (OGCT) characterization report.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

NSUF Report EBSD analyses on metallic fuel samples: Tips and improvements in sample preparation

EBSD (Electron Backscatter Diffraction) is an analytic technique used to evaluate the microstructure of a specimen. It can be used to evaluate interesting crystallographic data ranging from grains size to grain orientation, from grain boundaries to stresses. Moreover, in the field of nuclear materials EBSD can aid in estimating properties important for reactor performance, such as dislocation and residual strain [1]. EBSD patterns are generated by focusing a stationary electron gun on the specimen and detecting the backscatter electrons that satisfy Bragg conditions, and thus are diffracted by the crystal planes forming the so called Kikuchi bands. These bands correspond to each of the lattice diffracting crystal planes and are detected on a phosphor screen via a low-light CCD camera [2]. The patterns are generated within a small interaction volume located at a depth of less than 50-100 nm. Because of this, the data quality is extremely sensitive to the integrity of the crystallographic lattice order at the surface of the sample and thus to sample preparation and to oxidation [3]. While conventional sample preparation methods are widely used in materials science, they often do not lead to quality electron backscatter patterns needed for the characterization of nuclear materials [4]. This has been related by many authors to the challenges associated with handling radiological specimens, their rapid oxidation, and artifacts in such samples (e.g. high number of defects, precipitates and/or porosities) [4-8]. EBSD, however, can be an invaluable technique to evaluate microstructural evolution during fabrication and after irradiation at the required mesoscale for model and simulation. It also provides important information on grain structure necessary to understand irradiation effect, such as grain subdivision. Thus, it is of paramount importance to further the application of this technique to nuclear materials and especially irradiated fuels.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
NASA NTRS1979

Effect of sample quantity on the results of ferromagnetic resonance studies of lunar samples

Quantitative ferromagnetic resonance (FMR) measurements at 9.5 and 35 GHz were made on lunar fines in order to determine the amount of single domain FE(0) and to ascertain the effect of sample quantity on the results of these experiments. Samples containing more than 10 micrograms of Fe(0) in an X-band TE(104) cavity, or more than 0.11 micrograms in a Ka-band cavity can cause errors greater than 1% in the quantitative determination of Fe(0), as well as cause anomalous broadening of the FMR line. Theoretical calculations were derived to show this effect which results from a nonlinear response of the FMR experiment with the sample quantity. Using samples of nominal weights, the amount of Fe(0) determined at 34 GHz was 1.1-1.8 times greater than at 9.5 GHz, while the linewidths increased by a factor of 1.2. As the particle size increases, the ratio of Fe(0) determined at 35 GHz to that determined at 9.5 GHz increases, suggesting that the additional iron is due to larger spheroidal particles which change from multidomain to single domain at the larger fields.

Goldberg, J. B.↗
NASA NTRS1982

Image sampling, reconstruction, and the effect of sample-scene phasing

This paper is a 1-D analysis of the degradation caused by image sampling and interpolative reconstruction. The analysis includes the sample-scene phase as an explicit random parameter and provides a complete characterization of this image degradation as the sum of two terms: one term accounts for the mean effect of undersampling (aliasing) and nonideal reconstruction averaged over all sample-scene phases; the other term accounts for variations about this mean. The results of this paper have application to the design and performance analysis of image scanning, sampling, and reconstruction systems.

Park, S. K.↗
NASA NTRS1991

Post-flight characterization of optical system samples, thermal control samples, and detectors from LDEF experiment M0003, sub-experiments 6 and 13

Flight samples and control samples of optical and thermal control coatings were measured for hemispheric reflectance and transmission. The samples were exposed directly to the orbital environment, but were on the trailing edge of the LDEF satellite. Preliminary analysis shows no significant change in the reflectance of transmission values of most of the samples. Post-flight tests of avalanche photodiodes is also discussed.

Hodgson, Randall R.↗
NASA NTRS1992

Post-flight characterization of optical system samples, thermal control samples, and detectors from LDEF experiment M0003, sub-experiments 6 and 13

Flight samples and control samples of optical and thermal control coatings have been measured for hemispheric reflectance and transmission. Data was recorded for wavelengths from .25 microns to 18 microns. The samples were exposed directly to the orbital environment, but were on the trailing edge of the LDEF satellite. Preliminary analysis shows no significant change in the reflectance or transmission values of most of the samples. Post-flight tests of avalanche photodiodes have yielded results. The tests consist of measuring the following detector parameters: breakdown voltage for set values of reverse current, responsivity vs. bias voltage, noise equivalent power, and uniformity of photoresponse. The avalanche photodiodes were mounted on the leading edge of the LDEF satellite, but were shielded from the outside by a silver-coated teflon foil cover. Small puncture holes are present in the foil, probably caused by impact of particles in orbit. For most of the detectors, there has been no significant change in noise or response.

Randall R Hodgson↗
NASA NTRS1993

Collecting cometary soil samples? Development of the ROSETTA sample acquisition system

In the reference scenario of the ROSETTA CNRS mission, the Sample Acquisition System is mounted on the Comet Lander. Its tasks are to acquire three kinds of cometary samples and to transfer them to the Earth Return Capsule. Operations are to be performed in vacuum and microgravity, on a probably rough and dusty surface, in a largely unknown material, at temperatures in the order of 100 K. The concept and operation of the Sample Acquisition System are presented. The design of the prototype corer and surface sampling tool, and of the equipment for testing them at cryogenic temperatures in ambient conditions and in vacuum in various materials representing cometary soil, are described. Results of recent preliminary tests performed in low temperature thermal vacuum in a cometary analog ice-dust mixture are provided.

Coste, P. A.↗
NASA NTRS2004

Novel Sample-handling Approach for XRD Analysis with Minimal Sample Preparation

Sample preparation and sample handling are among the most critical operations associated with X-ray diffraction (XRD) analysis. These operations require attention in a laboratory environment, but they become a major constraint in the deployment of XRD instruments for robotic planetary exploration. We are developing a novel sample handling system that dramatically relaxes the constraints on sample preparation by allowing characterization of coarse-grained material that would normally be impossible to analyze with conventional powder-XRD techniques.

Sarrazin, P.↗
NASA NTRS2011

Sampling Theorem in Terms of the Bandwidth and Sampling Interval

An approach has been developed for interpolating non-uniformly sampled data, with applications in signal and image reconstruction. This innovation generalizes the Whittaker-Shannon sampling theorem by emphasizing two assumptions explicitly (definition of a band-limited function and construction by periodic extension). The Whittaker- Shannon sampling theorem is thus expressed in terms of two fundamental length scales that are derived from these assumptions. The result is more general than what is usually reported, and contains the Whittaker- Shannon form as a special case corresponding to Nyquist-sampled data. The approach also shows that the preferred basis set for interpolation is found by varying the frequency component of the basis functions in an optimal way.

Dean, Bruce H.↗
NASA NTRS2011

Measuring Sulfur Isotope Ratios from Solid Samples with the Sample Analysis at Mars Instrument and the Effects of Dead Time Corrections

The Sample Analysis at Mars (SAM) instrument suite comprises the largest science payload on the Mars Science Laboratory (MSL) "Curiosity" rover. SAM will perform chemical and isotopic analysis of volatile compounds from atmospheric and solid samples to address questions pertaining to habitability and geochemical processes on Mars. Sulfur is a key element of interest in this regard, as sulfur compounds have been detected on the Martian surface by both in situ and remote sensing techniques. Their chemical and isotopic composition can belp constrain environmental conditions and mechanisms at the time of formation. A previous study examined the capability of the SAM quadrupole mass spectrometer (QMS) to determine sulfur isotope ratios of SO2 gas from a statistical perspective. Here we discuss the development of a method for determining sulfur isotope ratios with the QMS by sampling SO2 generated from heating of solid sulfate samples in SAM's pyrolysis oven. This analysis, which was performed with the SAM breadboard system, also required development of a novel treatment of the QMS dead time to accommodate the characteristics of an aging detector.

Franz, H. B.↗
NASA NTRS2013

Hermetic Seal Designs for Sample Return Sample Tubes

Prototypes have been developed of potential hermetic sample sealing techniques for encapsulating samples in a ≈1-cm-diameter thin-walled sample tube that are compatible with IMSAH (Integrated Mars Sample Acquisition and Handling) architecture. Techniques include a heat-activated, finned, shape memory alloy plug; a contracting shape memory alloy activated cap; an expanding shape memory alloy plug; and an expanding torque plug. Initial helium leak testing of the shape memory alloy cap and finned shape memory alloy plug seals showed hermetic- seal capability compared against an industry standard of <1×10-8 atm-cc/s He. These tests were run on both clean tubes and dirty tubes dipped in MMS (Mojave Mars Simulant). The leak tests were also performed after thermal cycling between -135 and +55 ºC to ensure seal integrity after Martian diurnal cycles. Developmental testing is currently being done on the expanding torque plug, and expanding shape memory alloy plug seal designs. The finned shape memory alloy (SMA) plug currently shows hermetic sealing capability based on preliminary tests.

Younse, Paulo J.↗
NASA NTRS2021

Machine Vision based Sample-Tube Localization for Mars Sample Return

A potential Mars Sample Return (MSR) architecture is being jointly studied by NASA and ESA. As currently envisioned, the MSR campaign consists of a series of 3 missions: sample cache, fetch and return to Earth. In this paper, we focus on the fetch part of the MSR, and more specifically the problem of autonomously detecting and localizing sample tubes deposited on the Martian surface. Towards this end, we study two machine-vision based approaches: First, a geometrydriven approach based on template matching that uses hardcoded filters and a 3D shape model of the tube; and second, a data-driven approach based on convolutional neural networks (CNNs) and learned features. Furthermore, we present a large benchmark dataset of sample-tube images, collected in representative outdoor environments and annotated with ground truth segmentation masks and locations. The dataset was acquired systematically across different terrain, illumination conditions and dust-coverage; and benchmarking was performed to study the feasibility of each approach, their relative strengths and weaknesses, and robustness in the presence of adverse environmental conditions.

Detry, R.↗
NASA NTRSDate not supplied

Heating and Sampling Efficiency Evaluation for the Nephele Venus Cloud Sampling Mission Concept

Nephele [1] is a descent probe concept with a unique combination of entry (3D-CC+HEEET), sampling (flow-through passive impactors), and optics (laser-induced breakdown spectroscopy, or LIBS, and surface-enhanced Raman spectroscopy, or SERS), technologies with two key innovations (Figure 1). The first is the integration of the aerosol sampling inlet into the aeroshell body, allowing the possibility of sampling during passive descent without separation. The second is the use of the aerosol capture surface as an optical analysis substrate, allowing fast-cadence aerosol analysis via a dual optical spectrometer instead of mass spectrometry. Although this concept shares some features with other efforts such as Cupid’s Arrow [1] (single-body sample capture system), DAVINCI [2] and Venera-D [3] (use of an optical spectrometer), Nephele is unique in its physical integration of the sonde body, aerosol and gas sampler, and analysis instrumentation. This innovation is designed to eliminate the need for a controlled descent to achieve a detailed atmospheric aerosol transect, which offers in situ planetary science in a small spacecraft envelope. Aeroshell designs with inlets for free-falling sondes are well-understood, though not yet assessed for aerosol capture efficiency. A HEEET aeroshell with a specialized nose inlet material comprised of Carbon-Carbon is proposed for this mission concept.

Venus↗
NASA NTRSDate not supplied

Heating and Sampling Efficiency Evaluation for the Nephele Venus Cloud Sampling Mission Concept

Nephele is a descent probe concept with a unique combination of entry (3D-CC+HEEET), sampling (flow-through passive impactors), and optics (laser-induced breakdown spectroscopy, or LIBS, and surface-enhanced Raman spectroscopy, or SERS), technologies with two key innovations. The first is the integration of the aerosol sampling inlet into the aeroshell body, allowing the possibility of sampling during passive descent without separation. The second is the use of the aerosol capture surface as an optical analysis substrate, allowing fast-cadence aerosol analysis via a dual optical spectrometer instead of mass spectrometry. Although this concept shares some features with other efforts such as Cupid’s Arrow (single-body sample capture system), DAVINCI and Venera-D (use of an optical spectrometer), Nephele is unique in its physical integration of the sonde body, aerosol and gas sampler, and analysis instrumentation. This innovation is designed to eliminate the need for a controlled descent to achieve a detailed atmospheric aerosol transect, which offers in situ planetary science in a small spacecraft envelope. Aeroshell designs with inlets for free-falling sondes are well-understood, though not yet assessed for aerosol capture efficiency. A HEEET aeroshell with a specialized nose inlet material comprised of Carbon-Carbon is proposed for this mission concept.

Venus↗
NASA NTRS2012

Sample Sealing Approaches for Mars Sample Return Caching

Objective ot this project was to investigate sealing methods for encapsulating samples in 1 cm diameter thin-walled sample tubes applicable to future proposed Mars Sample Return Techniques implemented include a spring energized Teflon sleeve plug, a crimped tube seal, a heat-activated shape memory alloy plug, a shape memory alloy activated cap, a solder-based plug, and a solder-based cap

Mars Sample Return (MSR) mission↗
NASA NTRS2014

Detection and Quantification of Nitrogen Compounds in the First Drilled Martian Solid Samples by the Sample Analysis at Mars (SAM) Instrument Suite on the Mars Science Laboratory (MSL)

The Sample Analysis at Mars (SAM) instrument suite on the Mars Science Laboratory (MSL) Curiosity Rover detected both reduced and oxidized nitrogen-bearing compounds during the pyrolysis of surface materials at Yellowknife Bay in Gale Crater. Preliminary detections of nitrogen species include NO, HCN, ClCN, CH3CN, and TFMA (trifluoro-N-methyl-acetamide). Confirmation of indigenous Martian N-bearing compounds requires quantifying N contribution from the terrestrial derivatization reagents (e.g. N-methyl-N-tertbutyldimethylsilyltrifluoroacetamide, MTBSTFA and dimethylformamide, DMF) carried for SAM's wet chemistry experiment that contribute to the SAM background. Nitrogen species detected in the SAM solid sample analyses can also be produced during laboratory pyrolysis experiments where these reagents are heated in the presence of perchlorate, a compound that has also been identified by SAM in Mars solid samples.

Curiosity rover↗