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All sourcesNASA NTRSDOE OSTI
NASA NTRS2000

Mission Design Overview for Mars 2003/2005 Sample Return Mission

In May 2003, a new and exciting chapter in Mars exploration will begin with the launch of the first of three spacecraft that will collectively contribute toward the goal of delivering samples from the Red Planet to Earth. This mission is called Mars Sample Return (MSR) and will utilize both the 2003 and 2005 launch opportunities with an expected sample return in October 2008. NASA and CNES are major partners in this mission. The baseline mission mode selected for MSR is Mars orbit rendezvous (MOR), analogous in concept to the lunar orbit rendezvous (LOR) mode used for Apollo in the 1960s. Specifically, MSR will employ two NASA-provided landers of nearly identical design and one CNES-provided orbiter carrying a NASA payload of rendezvous sensors, orbital capture mechanisms, and an Earth entry vehicle (EEV). The high-level concept is that the landers will launch surface samples into Mars orbit, and the orbiter will retrieve the samples in orbit and then carry them back to Earth. The first element to depart for Mars will be one of the two landers. Currently, it is proposed that an intermediate class launch vehicle, such as the Boeing Delta 3 or Lockheed Martin Atlas 3A, will launch this 1800-kg lander from Cape Canaveral during the May 2003 opportunity. The lander will utilize a Type-1 transfer trajectory with an arrival at Mars in mid-December 2003. Landing will be aided by precision approach navigation and a guided hypersonic entry to achieve a touchdown accuracy of 10 km or better. Although the exact landing site has not yet been determined, it is estimated that lander resource constraints will limit the site to between 15 degrees north and south latitudes. Following touchdown, the lander will deploy a six-wheeled, 60-kg rover carrying an extensive suite of instruments designed to aid in the analysis of the local terrain and collection of core samples from selected rocks. The surface mission is currently designed around a concept called the surface traverse. Each traverse will involve the rover exploring a selected area of terrain up to 100 meters from the lander, the collection of rock core samples, and the delivery of the samples from the traverse back to a sample canister on the lander. Planning estimates indicate that up to three traverses may be possible during the expected 90-sol lifetime of the lander. The canister that will receive the samples from the rover will be attached to the top stage of a small solid-fueled rocket mounted to the deck of the lander. This rocket is called the Mars Ascent Vehicle (MAV) and consists of three stages weighing a total of about 140 kg. After the conclusion of the surface mission, the MAV will lift-off and insert the sample canister into a near-circular orbit with an altitude of about 600 km and inclination of 45 degrees. The sample canister will wait in this orbit until it is retrieved by the orbiter sometime in early 2007. In August 2005, the second lander and a CNES-provided orbiter weighing 2700 kg will depart for Mars. Currently, it is proposed that a single Ariane 5 provided by CNES will launch both of these two elements onto a Type-2 transfer trajectory. Although the orbiter and lander will be launched together, they will separate shortly after injection and will fly to Mars as two independent spacecraft. However, both spacecraft will perform a maneuver between 10 and 15 days after launch so that their arrival times at Mars differ by between 12 and 24 hours. This scheme will reduce the operational complexity at the encounter date. A set of four 60-kg surface probes will ride piggyback on the orbiter to Mars. These CNES-provided probes are called Netlanders and will serve as surface stations for scientific investigations independent of the Mars Sample Return goals. Starting approximately one month prior to arrival at Mars, the orbiter will begin to release the Netlanders one at a time. Each release cycle will take several days, and will include time for precision navigation to execute one or two maneuvers that will target the Netlanders to their proper landing site. All four deployment cycles will be completed prior to 10 days before arrival. Both the orbiter and lander will arrive in late-July 2006. Upon arrival, the lander will perform a precision landing and surface mission similar in concept to the one that was executed during the 2003 opportunity. Although the landing site for the 2005 opportunity has not been selected, it is expected to be different from the 2003 site to enhance the diversity of the collected samples. The orbiter's arrival at Mars will be highlighted by the first use of aerocapture to insert a spacecraft into a capture orbit around another planet. The choice of aerocapture, as opposed to a propulsive orbit insertion, was considered mission enabling due to a reduction of over 2000 m/s in mission AV. Aerocapture will be targeted to produce a 250 km x 1400 km capture orbit with an inclination of 45 degrees. Current analysis indicates that achieving this goal will require approximately six minutes of flight deep in the atmosphere with a targeted periapsis of approach of about 43 km. After factoring into account the penalty for carrying a heat shield to survive aerocapture, the net savings compared to a propulsive orbital insertion amounts to several hundred kilograms.

Lee, Wayne J.↗
NASA NTRS2000

NEA Multi-Chamber Sample Return Container with Hermetic Sealing

A sample return container is being developed by Honeybee Robotics to receive samples from a derivative of the Champollion/ST4 Sample Acquisition and Transfer Mechanism or other samplers such as the 'Touch and Go' Surface Sampler (TGSS), and then hermetically seal the samples for a sample return mission. The container is enclosed in a phase change material (PCM) chamber to prevent phase change during return and re-entry to earth. This container is designed to operate passively with no motors and actuators. Using the rotation axis of the TGSS sampler for interfacing, transferring and sealing samples, the container consumes no electrical power and therefore minimizes sample temperature change. The circular container houses multiple isolated canisters, which will be sealed individually for samples acquired from different sites or depths. The TGSS based sampler indexes each canister to the sample transfer position, below the index interface for sample transfer. After sample transfer is completed, the sampler indexes a seal carrier, which lines up seals with the openings of the canisters. The sampler moves to the sealing interface and seals the sample canisters one by one. The sealing interface can be designed to work with C-seals, knife edge seals and cup seals. This sample return container is being developed by Honeybee Robotics in collaboration with the JPL Exploration Technology program. A breadboard system of the sample return container has been recently completed and tested. Additional information is contained in the original extended abstract.

Rafeek, Shaheed↗
NASA NTRS2000

A Sample Return Container with Hermetic Seal

A sample return container is being developed by Honeybee Robotics to receive samples from a derivative of the Champollion/ST4 Sample Acquisition and Transfer Mechanism or other samplers and then hermetically seal samples for a sample return mission. The container is enclosed in a phase change material (PCM) chamber to prevent phase change during return and re-entry to earth. This container is designed to operate passively with no motors and actuators. Using the sampler's featured drill tip for interfacing, transfer-ring and sealing samples, the container consumes no electrical power and therefore minimizes sample temperature change. The circular container houses a few isolated canisters, which will be sealed individually for samples acquired from different sites or depths. The drill based sampler indexes each canister to the sample transfer position, below the index interface for sample transfer. After sample transfer is completed, the sampler indexes a seal carrier, which lines up seals with the openings of the canisters. The sampler moves to the sealing interface and seals the sample canisters one by one. The sealing interface can be designed to work with C-seals, knife edge seals and cup seals. Again, the sampler provides all sealing actuation. This sample return container and co-engineered sample acquisition system are being developed by Honeybee Robotics in collaboration with the JPL Exploration Technology program.

Kin Yuen Kong↗
NASA NTRS2009

Device Acquires and Retains Rock or Ice Samples

The Rock Baller is a sample acquisition tool that improves sample retention. The basic elements of the Rock Baller are the tool rotation axis, the hub, the two jaws, and the cutting blades, which are located on each of the jaws. The entire device rotates about the tool rotation axis, which is aligned parallel to the nominal normal direction of the parent rock surface. Both jaws also rotate about the jaw axis, which is perpendicular to the tool rotation axis, at a rate much slower than the rotation about the tool rotation axis. This movement gradually closes the jaws into a nearly continuous hemispherical shell that encloses the sample as it is cut from the parent rock. When required the jaws are opened to release the sample. The hemispherical cutting method eliminates the sample retention problems associated with existing sample acquisition methods that employ conventional cylindrical cutting. The resulting samples are hemispherical, or nearly hemispherical, and as a result the aspect ratio (sample depth relative to sample radius) is essentially fixed. This fixed sample aspect ratio may be considered a drawback of the Rock Baller method, as samples with a higher aspect ratio (more depth, less width) may be considered more scientifically valuable because such samples would allow for a broader inspection of the geological record. This aspect ratio issue can be ameliorated if the Rock Baller is paired with a device similar to the Rock Abrasion Tool (RAT) used on the Mars Exploration Rovers. The RAT could be used to first grind into the surface of the parent rock, after which the Rock Baller would extract a sample from a depth inside the rock that would not have been possible without first using the RAT. Other potential applications for this technology include medical applications such as the removal of tissue samples or tumors from the body, particularly during endoscopic, laparoscopic, or thoracoscopic surgeries.

Giersch, Louis R.↗
NASA NTRS2014

X-Ray Micro-Computed Tomography of Apollo Samples as a Curation Technique Enabling Better Research

X-ray micro-computed tomography (micro-CT) is a technique that has been used to research meteorites for some time and many others], and recently it is becoming a more common tool for the curation of meteorites and Apollo samples. Micro-CT is ideally suited to the characterization of astromaterials in the curation process as it can provide textural and compositional information at a small spatial resolution rapidly, nondestructively, and without compromising the cleanliness of the samples (e.g., samples can be scanned sealed in Teflon bags). This data can then inform scientists and curators when making and processing future sample requests for meteorites and Apollo samples. Here we present some preliminary results on micro-CT scans of four Apollo regolith breccias. Methods: Portions of four Apollo samples were used in this study: 14321, 15205, 15405, and 60639. All samples were 8-10 cm in their longest dimension and approximately equant. These samples were micro-CT scanned on the Nikon HMXST 225 System at the Natural History Museum in London. Scans were made at 205-220 kV, 135-160 microamps beam current, with an effective voxel size of 21-44 microns. Results: Initial examination of the data identify a variety of mineral clasts (including sub-voxel FeNi metal grains) and lithic clasts within the regolith breccias. Textural information within some of the lithic clasts was also discernable. Of particular interest was a large basalt clast (approx.1.3 cc) found within sample 60639, which appears to have a sub-ophitic texture. Additionally, internal void space, e.g., fractures and voids, is readily identifiable. Discussion: It is clear from the preliminary data that micro-CT analyses are able to identify important "new" clasts within the Apollo breccias, and better characterize previously described clasts or igneous samples. For example, the 60639 basalt clast was previously believed to be quite small based on its approx.0.5 sq cm exposure on the surface of the main mass. These scans show the clast to be approx.4.5 g, however (assuming a density of approx.3.5 g/cc). This is large enough for detailed studies including multiple geo-chronometers. This basalt clast is of particular interest as it is the largest Apollo 16 basalt, and it is the only mid-TiO2 basalt in the Apollo sample suite. By identifying the location of interesting clasts or grains within a sample, we will be able to make more informed decisions about where to cut a sample in order to best expose clasts of interest for future study. Moreover, knowing the location of internal defects (e.g., fractures) will allow more precise chipping and extraction of clasts or grains. By combining micro-CT scans with compositional techniques like micro x-ray fluorescence (particularly on sawn slabs), we will be able to provide even more comprehensive information to scientists trying to best select samples that fit their scientific needs.

Ziegler, R. A.↗
NASA NTRS2018

Curating NASA's Past, Present, and Future Extraterrestrial Sample Collections

As codified in NASA Policy Directive 7100.10F, the Astromaterials Acquisition and Curation Office at NASA Johnson Space Center (hereafter JSC Curation) is charged with curation of all extraterrestrial material under NASA control, including future NASA missions. JSC Curation curates all or part of nine astromaterial collections in seven clean room suites: (1) Apollo Samples (1969; ISO 6-7), (2) Luna Samples (from USSR; 1972; ISO 7), (3) Antarctic Meteorites (1976; ISO 7), (4) Cosmic Dust (1981; ISO 5), (5) Microparticle Impact Collection (formerly called Space Exposed Hardware; 1985; ISO 5), (6) Genesis Solar Wind Atoms (2004; ISO 4); (7) Stardust Comet Particles (2006; ISO 5), (8) Stardust Interstellar Particles (2006; ISO 5), (9) Hayabusa Asteroid Particles (from JAXA; 2010; ISO 5). In addition to the labs that house the samples, we have installed and maintained a wide variety of facilities and infrastructure required to support the clean-rooms: more than 10 different HEPA-filtered air-handling systems, ultrapure dry gaseous nitrogen systems, an ultrapure water system (UPW) and cleaning facilities to provide clean tools and equipment for the labs. We also have sample preparation facilities for making thin sections, microtome sections, and even focused ion-beam (FIB) sections to meet the research requirements of scientists. To ensure that we are keeping the samples as pristine as possible, we routinely monitor the cleanliness of our clean rooms and infrastructure systems. This monitoring includes: daily monitoring of the quality of our UPW, weekly airborne particle counts in the labs, monthly monitoring of the stable isotope composition of the gaseous N2 system, and annual measurements of inorganic or organic contamination in processing cabinets. We track within our databases the current and ever-changing characteristics of more than 250,000 individual samples across our various collections (including the 19,141 samples on loan to 433 Principal Investigators in 24 countries). The next sample return missions that NASA will participate in are Hayabusa2 and OSIRIS-REx (Origins Spectral Interpretation Resource Identification Security - Regolith Explorer). The designs for a new state-of-the-art suite of clean rooms to house these samples at JSC have been finalized. This includes separate ISO class 5 clean rooms to house each collection, a common ISO class 7 area for general use, an ISO class 7 microtome laboratory, and a separate thin section lab. Additionally, a new cleaning facility is being designed and procedures developed that will allow for enhanced cleaning of cabinets and tools in an inorganically, organically, and biologically clean manner. We are also designing a large multi-purpose Advanced Curation laboratory that will allow us to develop the techniques necessary to fully support the Hayabusa2 and OSIRIS-REx missions, as well as future possible sample return missions (e.g., Lunar Polar Volatiles, Mars, Comet Surface). A micro-CT (micro Computed Tomography) laboratory dedicated to the study of astromaterials has come online within JSC Curation, and we plan to add additional facilities that will enable non-destructive (or minimally-destructive) analyses of astromaterials in the near future (e.g., micro-XRF (micro X-Ray Fluorescence), confocal imaging Raman Spectroscopy). These facilities will be available to: (1) develop sample handling and storage techniques for future sample return missions, (2) be utilized by PET (Positron Emission Tomography) for future sample return missions, (3) for retroactive PET-style analyses of our existing collections, and (4) for periodic assessments of the existing sample collections.

Zeigler, Ryan A.↗
DOE OSTI2017

Purpose-Built UAVs for Physical Sampling of Trace Contamination at the Portsmouth Gaseous Diffusion Plant - 17331

The sampling of trace amounts of contamination, particularly of low-energy byproducts such as americium, presents a challenge for non-contact sensing. In many cases, such as determining the need for cleaning inside the exhaust shaft of the Waste Isolation Pilot Plant or sampling the walls of the enormous Gaseous Diffusion Plant at Portsmouth, it may be desirable to take physical swab samples at carefully distributed sample locations for analysis by mass spectrometry. Because of the danger posed to human workers in such scenarios, including risk of falls from lethal heights and exposure to low levels of radiation and the hassle of donning and doffing PPE, a low-cost robotic solution is desired. The inaccessibility of the heights involved suggest Unmanned Aerial Vehicle (UAV) solutions, rather than Unmanned Ground Vehicle (UGV) solutions, but conventional quadrotor UAVs are ill-suited to precise physical interaction with their surroundings. Quadrotors are under-actuated, rendering them non-holonomic and preventing the dexterous application of arbitrary generalized force/torques in interaction with the environment. At Purdue University, the authors have developed a number of novel UAV platforms suitable for dexterous interaction with the environment, making them ideal for such applications. These platforms can independently control forces in all directions, allowing for controlled application of the swab to the surface. Because of the scale of these structures (over 2 km in the case of the Gaseous Diffusion Plant), flight efficiency is of supreme importance. The Purdue team is took a variety of vehicles to the Gaseous Diffusion Plant for field trials on site in August, 2016. (With results available prior to the meeting.) The Purdue Dexterous Hexrotor is a fully-actuated Hexrotor capable of exerting forces in all six directions of force and torque. Operating alone or in swarms, the Dexterous Hexrotor can fly in free space, transition to contact through impact control, and sample the surface through force control. The Purdue I-BoomCopter is a tri-copter with an extra horizontal propeller that enables long-distance flight without pitching and the ability to apply closed-loop forces horizontally. Finally, the Purdue Tiltrotor VTOL is an under-actuated hybrid UAV that combines tilting rotors for vertical takeoff and landing, with a fixed-wing, flying-body design that is ultra-efficient for long-distance flight. The Dexterous Hexrotor provided two demonstrations of physical sampling of walls and crane rails. In sampling the large open sections of the inside of the plant, a small swarm of three UAVs is commanded to sample three distinct points on an internal map of the building. Human-supervised autonomy permits the UAVs to take off by themselves, find a clear elevation at which to fly through uncluttered space, navigate to their designated sampling points, and pause for confirmation by the human supervisor. The supervisor is presented with a video image of the intended sampling spot, which, if confirmed, the UAV will automatically approach and sample. The UAVs then autonomously return to the take-off spot. The second demo involved a single UAV searching upwards, then transitioning into 3-D SLAM mode to wait for a safe sampling spot on the 3-D scan to acquire the sample from the crane rail. The human supervisor, in this case, is responsible for ensuring the absence of cables and other obstacles. I-BoomCopter demonstrated its high-speed, long-distance coverage ability by making a few fast passes before homing in on a mock-up electrical panel with door, which it opened and closed. The dexterity of the I-BoomCopter results from its large propellers, which allow for controlled hovering and the horizontal thruster for applying forces of significant magnitude. Finally, the Tiltrotor VTOL is highly efficient in fixed-wing mode, but the tilt-rotor is under-actuated in hover. The tilt-rotor will take off vertically, then transition to high-speed, long-distance flight to make a number of passes inside the facility. The significance of these demos is the low-cost implementation of physical sampling over prescribable locations in difficult-to-reach areas of potentially contaminate facilities. To make this tractable over very large facilities, the demonstration of combinations of dexterous hovering ability and long-distance/high-speed flight is also in evidence. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

An Open Port Sampling Interface for Liquid Introduction Atmospheric Pressure Ionization Mass Spectrometry

RATIONALE: A simple method to introduce unprocessed samples into a solvent for rapid characterization by liquid introduction atmospheric pressure ionization mass spectrometry has been lacking. The continuous flow, self-cleaning open port sampling interface introduced here fills this void. METHODS: The open port sampling interface used a vertically aligned, co-axial tube arrangement enabling solvent delivery to the sampling end of the device through the tubing annulus and solvent aspiration down the center tube and into the mass spectrometer ionization source via the commercial APCI emitter probe. The solvent delivery rate to the interface was set to exceed the aspiration rate creating a continuous sampling interface along with a constant, self-cleaning spillover of solvent from the top of the probe. RESULTS: Using the open port sampling interface with positive ion mode APCI and a hybrid quadrupole time of flight mass spectrometer, rapid, direct sampling and analysis possibilities are exemplified with plastics, ballpoint and felt tip ink pens, skin, and vegetable oils. These results demonstrated that the open port sampling interface could be used as a simple, versatile and self-cleaning system to rapidly introduce multiple types of unprocessed, sometimes highly concentrated and complex, samples into a solvent flow stream for subsequent ionization and analysis by mass spectrometry. The basic setup presented here could be incorporated with any self-aspirating liquid introduction ionization source (e.g., ESI, APCI, APPI, ICP, etc.) or any type of atmospheric pressure sampling ready mass spectrometer system. CONCLUSIONS: The open port sampling interface provides a means to introduce and quickly analyze unprocessed solid or liquid samples with liquid introduction atmospheric pressure ionization source without fear of sampling interface or ionization source contamination.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2016

Evaluating Composite Sampling Methods of Bacillus Spores at Low Concentrations

Restoring facility operations after the 2001 Amerithrax attacks took over three months to complete, highlighting the need to reduce remediation time. The most time intensive tasks were environmental sampling and sample analyses. Composite sampling allows disparate samples to be combined, with only a single analysis needed, making it a promising method to reduce response times. We developed a statistical experimental design to test three different composite sampling methods: 1) single medium single pass composite: a single cellulose sponge samples multiple coupons; 2) single medium multi-pass composite: a single cellulose sponge is used to sample multiple coupons; and 3) multi-medium post-sample composite: a single cellulose sponge samples a single surface, and then multiple sponges are combined during sample extraction. Five spore concentrations of Bacillus atrophaeus Nakamura spores were tested; concentrations ranged from 5 to 100 CFU/coupon (0.00775 to 0.155CFU/cm 2 , respectively). Study variables included four clean surface materials (stainless steel, vinyl tile, ceramic tile, and painted wallboard) and three grime coated/dirty materials (stainless steel, vinyl tile, and ceramic tile). Analysis of variance for the clean study showed two significant factors: composite method (p-value < 0.0001) and coupon material (p-value = 0.0008). Recovery efficiency (RE) was higher overall using the post-sample composite (PSC) method compared to single medium composite from both clean and grime coated materials. RE with the PSC method for concentrations tested (10 to 100 CFU/coupon) was similar for ceramic tile, painted wall board, and stainless steel for clean materials. RE was lowest for vinyl tile with both composite methods. Statistical tests for the dirty study showed RE was significantly higher for vinyl and stainless steel materials, but significantly lower for ceramic tile. These results suggest post-sample compositing can be used to reduce sample analysis time when responding to a Bacillus anthracis contamination event of clean or dirty surfaces.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2022

Analysis of DWPF Sludge Batch 6 (Macrobatch 7): Pour Stream Glass Samples

The Defense Waste Processing Facility (DWPF) began processing Sludge Batch 6 (SB6), also referred to as Macrobatch 7 (MB7), in June 2010. SB6 is a blend of the heel of Tank 40 from Sludge Batch 5 (SB5), H-Canyon Np transfers and SB6 that was transferred to Tank 40 from Tank 51.1 SB6 was processed using Frit 418. Sludge is received into the DWPF Chemical Processing Cell (CPC) and is processed through the Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator Tank (SME). The treated sludge slurry is then transferred to the Melter Feed Tank (MFT) and fed to the melter. During processing of each sludge batch, the DWPF is required to take at least one glass sample to meet the objectives of the Glass Product Control Program (GPCP) and to complete the necessary Production Records so that the final glass product may be disposed of at a Federal Repository. The DWPF requested various analyses of radioactive glass samples obtained from the melter pour stream during processing of SB6 as well as reduction/oxidation (REDOX) analysis of MFT samples to determine the impact of Argon bubbling. Sample analysis followed the Task Technical and Quality Assurance Plan (TTQAP) and an Analytical Study Plan (ASP). Four Pour Stream (PS) glass samples and two MFT slurry samples were delivered to the Savannah River National Laboratory (SRNL) from the DWPF. Table 1-1 lists the sample information for each pour stream glass sample. SB6 PS3 (S03472) was selected as the official pour stream sample for SB6 and full analysis was requested. This report details the visual observations of the as-received SB6 PS No.3 glass sample as well as results for the chemical composition, Product Consistency Test (PCT), radionuclide content, noble metals, and glass density. REDOX results will be provided for all four pour stream samples and vitrified samples of MFT-558 and MFT-568A. Where appropriate, data from other pour stream samples will be provided.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Analysis of Tank 38H (HTF-38-16-80, 81) and Tank 43H (HTF-43-16-82, 83) Samples for Support of the Enrichment Control and Corrosion Control Programs

SRNL analyzed samples from Tank 38H and Tank 43H to support ECP and CCP. The total uranium in the Tank 38H surface sample was 57.6 mg/L, while the sub-surface sample was 106 mg/L. The Tank 43H samples ranged from 50.0 to 51.9 mg/L total uranium. The U-235 percentage was consistent for all four samples at 0.62%. The total uranium and percent U-235 results appear consistent with recent Tank 38H and Tank 43H uranium measurements. The Tank 38H plutonium results show a large difference between the surface and sub-surface sample concentrations and somewhat higher concentrations than previous samples. The Pu-238 concentration is more than forty times higher in the Tank 38H sub-surface sample than the surface sample. The surface and sub-surface Tank 43H samples contain similar plutonium concentrations and are within the range of values measured on previous samples. The four samples analyzed show silicon concentrations somewhat higher than the previous sample with values ranging from 104 to 213 mg/L.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Analysis of Tank 38H (HTF-38-19-18, -19) and Tank 43H (HTF-43-19-20, -21) Samples for Support of the Enrichment Control and Corrosion Control Programs

SRNL analyzed samples from Tank 38H and Tank 43H to support ECP and CCP. Overall, the results of the analysis indicate the concentrations of species in the Tank 38H surface sample increased significantly from the previous sample with the sodium concentration increasing from 1.09 M in the previous sample to 3.19 M in the current sample. However, it should be noted that the previous Tank 38H surface sample was very dilute compared with typical Tank 38H samples of the recent past. The Tank 38H sub-surface sample shows a composition fairly similar to the previous sample’s composition. Both the Tank 43H surface and sub-surface samples appear slightly more dilute than the previous samples based on the sodium concentrations. For both Tank 38H and Tank 43H, the subsurface samples appear slightly more concentrated for most species than the surface samples. These results indicate some success in increasing the salt solution concentration and reducing stratification in Tank 38H, but some stratification is still evident in both Tank 38H and Tank 43H.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Analysis of Tank 23H (HTF-23-19-23, -24, -25) Samples for Support of the Enrichment Control and Corrosion Control Programs

SRNL analyzed samples from Tank 23H to support ECP and CCP. The results of the analysis indicate the concentrations of species in Tank 23H increase with depth in the tank. The sample obtained from the lowest level of 60” from the bottom of the tank shows the highest concentrations for most species analyzed. The surface sample and the 140” sub-surface sample show similar compositions with the sub-surface sample being slightly more concentrated, and both are more dilute than the lowest 60” sub-surface sample for most species analyzed. The total uranium concentration in the three Tank 23H samples show a slight increase from the surface sample to the next lower sub-surface sample, but then a slight decrease in the uranium concentration in the lowest sub-surface sample. The U-235 weight fraction ranges from 0.94-1.2% in the Tank 23H samples. The sum of the major cations versus the sum of the major anions shows a difference of ~5% or less for all three of the Tank 23H samples indicating good data quality for the non-radioactive analytes in the table. Small %RSD values for the replicate analyses with the exception of species close to the detection limit (e.g., Fe) provide another indication of good data quality for the non-radioactive species. The silicon concentrations measured in the Tank 23H samples were all below detection.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Summary of Expedited Results from Samples Supporting Tank Closure Cesium Removal (TCCR) Batch 3

Savannah River Remediation (SRR) is currently operating the Tank Closure Cesium Removal (TCCR) process to remove 137 Cs from tank waste supernate using an ion exchange process. As part of that process, Savannah River National Laboratory (SRNL) receives and analyzes samples in support of the qualification of each batch to be processed. SRNL recently received supernate samples retrieved from Tank 10H as well as in-tank batch contact samples for characterization in support of qualifying Batch 3 for processing through the TCCR unit. SRNL received and characterized a set of dip samples collected from Tank 10H (one surface and one variable depth sample). No solids were observed in either sample and therefore the samples were combined, and a suite of analyses were performed on the composite sample. The density of the combined sample was 1.174 g/mL (0.18 %RSD), which was consistent with the measured sodium concentration of 3.54 M (0.08 %RSD). The 137Cs activity in the sample was 4.75E+07 dpm/mL (4.28 %RSD) and the total Cs concentration was calculated to be 1.54 mg/L (1.16E-05 M). The in-tank batch contact samples consist of 0.1 g of crystalline silicotitanate (CST) contained within a teabag device. Duplicate samples were submerged in Tank 10H supernate for a period of about 13 days, after which time they were retrieved and transferred to SRNL for analysis. At SRNL the CST was rinsed to remove excess salt solution and the CST was then air dried before being digested for analysis. Results of the analysis indicated a 137 Cs loading of 3.66E+10 ± 1.40E+09 dpm/g or 16.5 ± 0.63 Ci/kg CST . This value represents a bounding upper limit as it includes the addition of two sigma uncertainty from replicate analysis of the individual teabag samples as well as the addition of the small amount of 137 Cs activity measured in the rinse solutions. The above values are based on the air-dried mass of CST. Correcting to the true dry mass using a F-factor of 0.8191 results in a maximum loading of 20.2 ± 0.77 Ci/kg CST .

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

The SDSS-IV MaNGA Sample: Design, Optimization, and Usage Considerations

We describe the sample design for the SDSS-IV MaNGA survey and present the final properties of the main samples along with important considerations for using these samples for science. Our target selection criteria were developed while simultaneously optimizing the size distribution of the MaNGA integral field units (IFUs), the IFU allocation strategy, and the target density to produce a survey defined in terms of maximizing signal-to-noise ratio, spatial resolution, and sample size. Our selection strategy makes use of redshift limits that only depend on i-band absolute magnitude (M {sub i}), or, for a small subset of our sample, M {sub i} and color (NUV − i). Such a strategy ensures that all galaxies span the same range in angular size irrespective of luminosity and are therefore covered evenly by the adopted range of IFU sizes. We define three samples: the Primary and Secondary samples are selected to have a flat number density with respect to M {sub i} and are targeted to have spectroscopic coverage to 1.5 and 2.5 effective radii (R {sub e}), respectively. The Color-Enhanced supplement increases the number of galaxies in the low-density regions of color–magnitude space by extending the redshift limits of the Primary sample in the appropriate color bins. The samples cover the stellar mass range 5×10{sup 8}⩽M{sub ∗}⩽3×10{sup 11} M{sub ⊙} h{sup −2} and are sampled at median physical resolutions of 1.37 and 2.5 kpc for the Primary and Secondary samples, respectively. We provide weights that will statistically correct for our luminosity and color-dependent selection function and IFU allocation strategy, thus correcting the observed sample to a volume-limited sample.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2021

Ice-nucleating particles in precipitation samples from the Texas Panhandle

Ice-nucleating particles (INPs) influence the formation of ice crystals in clouds and many types of precipitation. This study reports unique properties of INPs collected from 42 precipitation samples in the Texas Panhandle region from June 2018 to July 2019. We used a cold stage instrument called the West Texas Cryogenic Refrigerator Applied to Freezing Test system to estimate INP concentrations per unit volume of air (nINP) through immersion freezing in our precipitation samples with our detection capability of >0.006 INP L -1 . A disdrometer was used for two purposes: (1) to characterize the ground-level precipitation type and (2) to measure the precipitation intensity as well as size of precipitating particles at the ground level during each precipitation event. While no clear seasonal variations of n INP values were apparent, the analysis of yearlong ground-level precipitation observation as well as INPs in the precipitation samples showed some INP variations, e.g., the highest and lowest n INP values at -25°C both in the summer for hail-involved severe thunderstorm samples (3.0 to 1130 INP L -1 ), followed by the second lowest at the same temperature from one of our snow samples collected during the winter (3.2 INP L -1 ). Furthermore, we conducted bacteria community analyses using a subset of our precipitation samples to examine the presence of known biological INPs. In parallel, we also performed metagenomics characterization of the bacterial microbiome in suspended ambient dust samples collected at commercial open-lot livestock facilities (cattle feedyards hereafter) in the Texas Panhandle (i.e., the northernmost counties of Texas, also known as “West Texas”) to ascertain whether local cattle feedyards can act as a source of bioaerosol particles and/or INPs found in the precipitation samples. Some key bacterial phyla present in cattle feedyard samples appeared in precipitation samples. However, no known ice nucleation active species were detected in our samples. Overall, our results showed that cumulative n INP in our precipitation samples below -20°C could be high in the samples collected while observing > 10 mm h -1 precipitation with notably large hydrometeor sizes and an implication of cattle feedyard bacteria inclusion.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1993

Investigation of spectral analysis techniques for randomly sampled velocimetry data

It is well known that velocimetry (LV) generates individual realization velocity data that are randomly or unevenly sampled in time. Spectral analysis of such data to obtain the turbulence spectra, and hence turbulence scales information, requires special techniques. The 'slotting' technique of Mayo et al, also described by Roberts and Ajmani, and the 'Direct Transform' method of Gaster and Roberts are well known in the LV community. The slotting technique is faster than the direct transform method in computation. There are practical limitations, however, as to how a high frequency and accurate estimate can be made for a given mean sampling rate. These high frequency estimates are important in obtaining the microscale information of turbulence structure. It was found from previous studies that reliable spectral estimates can be made up to about the mean sampling frequency (mean data rate) or less. If the data were evenly samples, the frequency range would be half the sampling frequency (i.e. up to Nyquist frequency); otherwise, aliasing problem would occur. The mean data rate and the sample size (total number of points) basically limit the frequency range. Also, there are large variabilities or errors associated with the high frequency estimates from randomly sampled signals. Roberts and Ajmani proposed certain pre-filtering techniques to reduce these variabilities, but at the cost of low frequency estimates. The prefiltering acts as a high-pass filter. Further, Shapiro and Silverman showed theoretically that, for Poisson sampled signals, it is possible to obtain alias-free spectral estimates far beyond the mean sampling frequency. But the question is, how far? During his tenure under 1993 NASA-ASEE Summer Faculty Fellowship Program, the author investigated from his studies on the spectral analysis techniques for randomly sampled signals that the spectral estimates can be enhanced or improved up to about 4-5 times the mean sampling frequency by using a suitable prefiltering technique. But, this increased bandwidth comes at the cost of the lower frequency estimates. The studies further showed that large data sets of the order of 100,000 points, or more, high data rates, and Poisson sampling are very crucial for obtaining reliable spectral estimates from randomly sampled data, such as LV data. Some of the results of the current study are presented.

Sree, Dave↗
NASA NTRS2002

A Draft Protocol for Detecting Possible Biohazards in Martian Samples Returned to Earth

In preparation for missions to Mars that will involve the return of samples, it is necessary to prepare for the safe receiving, handling, testing, distributing, and archiving of martian materials here on Earth. Previous groups and committees have studied selected aspects of sample return activities, but a specific protocol for handling and testing of returned -=1 samples from Mars remained to be developed. To refine the requirements for Mars sample hazard testing and to develop criteria for the subsequent release of sample materials from precautionary containment, NASA Planetary Protection Officer, working in collaboration with CNES, convened a series of workshops to produce a Protocol by which returned martian sample materials could be assessed for biological hazards and examined for evidence of life (extant or extinct), while safeguarding the samples from possible terrestrial contamination. The Draft Protocol was then reviewed by an Oversight and Review Committee formed specifically for that purpose and composed of senior scientists. In order to preserve the scientific value of returned martian samples under safe conditions, while avoiding false indications of life within the samples, the Sample Receiving Facility (SRF) is required to allow handling and processing of the Mars samples to prevent their terrestrial contamination while maintaining strict biological containment. It is anticipated that samples will be able to be shipped among appropriate containment facilities wherever necessary, under procedures developed in cooperation with international appropriate institutions. The SRF will need to provide different types of laboratory environments for carrying out, beyond sample description and curation, the various aspects of the protocol: Physical/Chemical analysis, Life Detection testing, and Biohazard testing. The main principle of these tests will be described and the criteria for release will be discussed, as well as the requirements for the SRF and its personnel.

Viso, M.↗