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NASA NTRS2020

Composite Piezoelectric Resonator 1D Modeling with Loss

Abstract – Maximizing the benefit of applying piezoelectric materials in composite structures, which are a mix of piezoelectric and elastic elements, requires analytical modeling. In this paper we describe two main classes of resonators and how to model using network equivalent including material losses. These include extensional devices where the layer areas are parallel to the direction of wave travel as found in a variety of thickness or length mode transducers (BC. Stress T1 = T2 at boundary) and transverse mode resonators (BC. Strain S1 = S2 at boundary) where the major layer area is perpendicular to the wave direction as is found in radial mode or length thickness mode composite resonators. In order to illustrate these models we will use Mason’s equivalent circuits with elastic, dielectric and piezoelectric loss. It is noted that in order to maintain consistency with the linear equations of piezoelectricity and the wave equation care is required when applying complex loss coefficients to the models. Although these techniques are applicable to other models we use Mason’s network equivalent circuit because it is intuitive for composite modeling due to the frequency independent turns ratio and the independence of the equations describing the elastic layers from the adjoining layer properties which aids in understanding the boundary conditions to impose on the layer boundaries. We will present network models for a variety of applications with loss and show how to calculate their impedance spectra, interface stress, strain velocity and displacement spectra.

Sherrit, Stewart↗

DOE OSTI2021

The impact of simultaneous inoculation of Pseudomonas aeruginosa, Staphylococcus aureus , and Candida albicans on rodent burn wounds

Burn wound infection often involves a diverse combination of bacterial and fungal pathogens. In this study, we characterize the mixed species burn wound infection by inoculating the burn surface with 1 × 10 3/4/5 CFU of Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans in a 1:1:1 ratio. Using the revised Walker–Mason scald burn rat model, 168 male Sprague-Dawley rats (350–450 g) subject to ~10% TBSA burn injury, with or without inoculation, were evaluated for 11 days after burn. In the wound, P. aeruginosa and S. aureus formed robust biofilms as determined by the bacterial tissue load, ~1 × 10 9 CFU/g, and expression of key biofilm genes. Interestingly, within 3 days C. albicans achieved tissue loads of ~1 × 10 6 CFU/g, but its numbers were significantly reduced beyond the limit of detection in the burn wound by day 7 in partial-thickness injuries and by day 11 in full-thickness injuries. The pathogenic biofilms contributed to burn depth progression, increased release of HMGB-1 into circulation from injured tissue, and significantly elevated the numbers of circulating innate immune cells (Neutrophils, Monocytes, and Basophils). This robust model of multi-species burn wound infection will serve as the basis for the development of new antimicrobials for combating biofilm-based wound infections.

60 APPLIED LIFE SCIENCES↗

NASA NTRS1973

Minor and trace elements in some meteoritic minerals.

Despite the information available (Mason, 1971) on trace elements in different types of meteorites, relatively little is known about the distribution of these elements among the individual mineral phases. The mineral phases including olivine, orthopyroxene, clinipyroxene, troilite, nickel-iron, plagioclase, chromite, and the phosphates were separated from several meteorites. The purified minerals were analyzed for trace and minor elements by spark source mass spectrometry and instrumental neutron activation analysis. The elements are classified as siderophile, lithophile, and chalcophile.

Allen, R. O., Jr.↗

NASA NTRS1975

Energy dependence of the Si/Fe ratio in the galactic cosmic rays

New measurements are reported of the Si/Fe ratio and the differential energy spectra of galactic cosmic-ray Si and Fe, taking into account the energy range from 35 MeV to 4 GeV per nucleon. The measured data were obtained with the aid of satellite and balloon-borne instrumentation. It is found that for the region below 1 GeV per nucleon the local interstellar spectra computed are consistent with previous galactic cosmic-ray propagation models obtained by Shapiro and Silberberg (1970) and Mason (1972).

Garcia-Munoz, M.↗

NASA NTRS1982

Infrared photometry of the X-ray binary 2A 1822-371 - A model for the ultraviolet, optical, and infrared light curve

The X-ray source 2A 1822-371 may be prototypical of a class of accreting close binary systems in which the X-ray emission is diffused by a cloud of ionized material which is associated with the accretion disk. The present investigation provides a report on infrared photometry of 2A 1822-371 in the J (1.25 micrometer), H (1.65 micrometer), and K (2.2 micrometer) bands. A complete 5.57 hr light curve has been obtained at J which makes it possible to extend the investigations of the energy dependence of the ultraviolet and optical curve begun by Mason and Cordova (1982). The work conducted by White and Holt (1982) is extended to the long wavelength light curve by incorporating the influence of emission from the inner and outer rim of the disk and from the companion star. Including such effects, and assuming that reprocessed X rays are the major source of light at wavelengths greater than 1100 A, it is found possible to reproduce the morphology and energy dependence which is observed in the light curve of 2A 1822-371 from the far-ultraviolet to the near-infrared.

Mason, K. O.↗

NASA NTRS1983

Atomic calculations for the Fe XX X-ray lines

The atomic data presented here and in Bhatia and Mason (1980) allow the calculation of theoretical intensity ratios for all the EUV, UV, and X-ray lines from Fe XX. Tabulations are presently given for the transitions between levels in the 2s2 2p3, 2s2 2p2 3s, and 2s2 2p2 3d configurations of Fe(19+), and electron collision strengths are calculated by means of the 'distorted wave' approximation. In addition to the theoretical X-ray line intensity ratios, new spectral line identifications from a solar flare are presented.

Mason, H. E.↗

NASA NTRS1986

Further atomic calculations for Fe XXIII

Electron collision strengths for Fe XXIII have been obtained using the 'distorted wave' approximation. Previous results (Bhatia and Mason, 1981) were obtained including the configurations 2s(2), 2s2p, 2p(2), 2s3s, 2s3p, and 2s3d. In this paper, the correlation configurations 2p3s, 2p3p and 2p3d have also been included in the solution of the electron scattering problem.

Bhatia, A. K.↗

NASA NTRS1986

Theoretical intensity ratios for the X-ray lines from Ca XV

Electron collision strengths for Ca XV have been obtained using the 'distorted wave' approximation. Previous results (Mason, 1975; Dere et al., 1979) were obtained for the configurations 2s(2)2p(2), 2s2P(3), 2p(4). This paper presents results for transitions 2s(2)2p(2)-2s(2)2p3s, 2s(2)2p3d which give rise to lines in the X-ray spectra of solar active regions and flares.

Bhatia, A. K.↗

NASA NTRS2012

Active Region Moss: Doppler Shifts from Hinode/EIS Observations

Studying the Doppler shifts and the temperature dependence of Doppler shifts in moss regions can help us understand the heating processes in the core of the active regions. In this paper we have used an active region observation recorded by the Extreme-ultraviolet Imaging Spectrometer (EIS) onboard Hinode on 12-Dec- 2007 to measure the Doppler shifts in the moss regions. We have distinguished the moss regions from the rest of the active region by defining a low density cut-off as derived by Tripathi et al. (2010). We have carried out a very careful analysis of the EIS wavelength calibration based on the method described in Young, O Dwyer and Mason (2012). For spectral lines having maximum sensitivity between log T = 5.85 and log T = 6.25 K, we find that the velocity distribution peaks at around 0 km/s with an estimated error of 4 km/s. The width of the distribution decreases with temperature. The mean of the distribution shows a blue shift which increases with increasing temperature and the distribution also shows asymmetries towards blue-shift. Comparing these results with observables predicted from different coronal heating models, we find that these results are consistent with both steady and impulsive heating scenarios. Further observational constraints are needed to distinguish between these two heating scenarios.

Tripathi, Durgesh↗

NASA NTRSDate not supplied

Spaceflight Associated Neuro-Ocular Syndrome: A Brief for Astronaut Candidates

INTRODUCTION: Spaceflight Associated Neuro-ocular Syndrome (SANS) was first described in 2011 as a clinical process involving degradation of visual acuity and structural changes of the eye when exposed to microgravity. This syndrome poses a risk to astronaut vision, safety, and mission performance, especially during extended-duration missions. The modern astronaut cohort is a diverse group of men and women including scientists, engineers, teachers, pilots, business professionals, and artists. Given their diverse backgrounds, it is imperative all crews are educated on SANS risks and potential countermeasures. This education must be comprehensive and easily understood, regardless of academic background or specific expertise. TOPIC: A PowerPoint was created to serve as a presentation and stand-alone educational aid for all astronaut candidates (ASCANS). This medium was chosen as it can be updated dynamically as new information emerges. The brief was split into sections to facilitate organized delivery of complex content in easy-to-understand components. Sections included descriptive statistics, signs and symptoms, outcomes, myths and ongoing research, countermeasures, ongoing surveillance, and unknown and future directions. More research is necessary in order to understand this syndrome, and without continued ASCAN participation in research, acquisition of data will not be possible. These efforts will become increasingly critical with deep space and exploration missions. APPLICATION: We recommend regular use of this brief for all ASCANS, and potentially veteran crewmembers, given the high risks and potentially poor outcomes associated with SANS. For ASCANS, recommendations include that this brief be provided at the start of their training, with a bi-annual refresher course for all astronauts. This ensures they are current on SANS information, given the dynamic nature of this syndrome. Additionally, this brief will be made available to all as a self-study aid, utilized as a refresher immediately prior to launch. It is anticipated that this brief will promote the health, safety, and wellbeing of professional and private crews alike, during and after long-duration spaceflight. RESOURCES: Brunstetter, T., Tarver, B., & Tsung, A. (2022, October). Spaceflight Associated Neuro-ocular Syndrome (Sans) and its Risk to Nasa Astronauts. JSC Aerospace Medicine Clerkship. Houston, TX; Lyndon B. Johnson Space Center. Laurie, S. S., Macias, B. R., Pardon, L. P., Brunstetter, T., Tarver, W. J., Gibson, C. R., Greenwald, S. H., Jasien, K. V., Mason, S., & Tsung, A. (2022). (rep.). Evidence Report: Risk of Spaceflight Associated Neuro-ocular Syndrome (SANS). Houston, TX: National Aeronautics and Space Administration. Mader, T. H., Gibson, C. R., Pass, A. F., Kramer, L. A., Lee, A. G., Fogarty, J., ... & Polk, J. D. (2011). Optic disc edema, globe flattening, choroidal folds, and hyperopic shifts observed in astronauts after long-duration space flight. Ophthalmology, 118(10), 2058-2069. LEARNING OBJECTIVES: • The audience will be able to describe current Spaceflight Associated Neuro-ocular Syndrome (SANS) findings, significance, and countermeasures. • The audience will understand the importance of astronauts’ familiarity with SANS prior to flying and the large risks associated with this syndrome. CME QUESTIONS (3 QUESTIONS, MULTIPLE CHOICE A-D): 1. What is the approximate prevalence rate of SANS in astronauts? A. 22% B. 50% C. 66% D. 80% Answer: C. 2. Which of the ocular findings are NOT associated with SANS? A. Optic disc edema B. Retinal detachment C. Globe flattening D. Chorioretinal folds Answer: B. 3. Which of the following diagnostic technologies are NOT available in-flight? A. Ocular ultrasound B. Retinal photography C. MRI Orbit D. Optical Coherence Tomography (OCT) Answer: C.

Sara Stroble Mason↗

NASA NTRS2026

Swamp Works Regolith Compaction Technologies

While the level of compaction below the lunar surface increases quickly after only a few cm of depth, in many cases during a construction mission there will be a need to excavate and transport regolith to a new location for cut-and-fill or horizontal construction of structures such as berms. In these cases to achieve high levels of bulk density, compaction must be per-formed. Additionally, in some cases surface technolo-gies such as systems that sinter/melt the surface may desire the maximum possible compaction at the sur-face to improve melting/heating performance and the final material strength properties. Kennedy Space Center’s (KSC) Swamp Works has developed two means of compaction, lunar and mar-tian compaction. Planetary Autonomous Compaction Technology (PACT) which is part of the Multifunction End Effector for Regolith Compaction Acquisition and Transfer (MEERCAT [1]) robotic arm end effector system’s capabilities and the Site Preparation Tooling for Operations on Mobility Platforms (STOMP [2]) vibratory roller compactor. PACT on MEERCAT has been demonstrated to a TRL 5 and STOMP to a TRL 4 in ambient testing. The results of PACT on MEERCAT and STOMP testing will be shared with results for various simulants including BP-1, ICN-LHT-1G (aka CSM-LHT-1G), RDW-LHT-1GH (a simulant developed for the Mason Tipping Point to match characteristics of ICN-LHT-1G), and Exolith LHS-1E. This will also include discus-sions on methods used to verify relative density before and after compaction and means to verify density effects below depth. To calculate relative density, maximum and minimum densities for simulants were taken from literature [3] [4] [5] and additional lab test-ing (publication in work).

vibration↗

NASA NTRSDate not supplied

Swamp Works Regolith Compaction Technologies

While the level of compaction below the lunar surface increases quickly after only a few cm of depth, in many cases during a construction mission there will be a need to excavate and transport regolith to a new location for cut-and-fill or horizontal construction of structures such as berms. In these cases to achieve high levels of bulk density, compaction must be per-formed. Additionally, in some cases surface technologies such as systems that sinter/melt the surface may desire the maximum possible compaction at the sur-face to improve melting/heating performance and the final material strength properties. Kennedy Space Center’s (KSC) Swamp Works has developed two means of compaction, lunar and mar-tian compaction. Planetary Autonomous Compaction Technology (PACT) which is part of the Multifunction End Effector for Regolith Compaction Acquisition and Transfer (MEERCAT) robotic arm end effector system’s capabilities and the Site Preparation Tooling for Operations on Mobility Platforms (STOMP) vibratory roller compactor. PACT on MEERCAT has been demonstrated to a TRL 5 and STOMP to a TRL 4 in ambient testing. The results of PACT on MEERCAT and STOMP testing will be shared with results for various simulants including BP-1, ICN-LHT-1G (aka CSM-LHT-1G), RDW-LHT-1GH (a simulant developed for the Mason Tipping Point to match characteristics of ICN-LHT-1G), and Exolith LHS-1E. This will also include discussions on methods used to verify relative density before and after compaction and means to verify density effects below depth. To calculate relative density, maximum and minimum densities for simulants were taken from literature and additional lab testing (publication in work).

redwire↗

DOE OSTI2021

Crystal structures of inhibitor complexes of M‐PMV protease with visible flap loops

Abstract Mason‐Pfizer monkey virus protease (PR) was crystallized in complex with two pepstatin‐based inhibitors in P 1 space group. In both crystal structures, the extended flap loops that lock the inhibitor/substrate over the active site, are visible in the electron density either completely or with only small gaps, providing the first observation of the conformation of the flap loops in dimeric complex form of this retropepsin. The H‐bond network in the active site (with D26N mutation) differs from that reported for the P 2 1 crystal structures and is similar to a rarely occurring system in HIV‐1 PR.

Wosicki, Stanislaw↗

DOE OSTI2024

Quantifying electron transport in aggregated colloidal suspensions in the strong flow regime

Electron transport in complex fluids, biology, and soft matter is a valuable characteristic in processes ranging from redox reactions to electrochemical energy storage. These processes often employ conductor–insulator composites in which electron transport properties are fundamentally linked to the microstructure and dynamics of the conductive phase. While microstructure and dynamics are well recognized as key determinants of the electrical properties, a unified description of their effect has yet to be determined, especially under flowing conditions. In this work, the conductivity and shear viscosity are measured for conductive colloidal suspensions to build a unified description by exploiting both recent quantification of the effect of flow-induced dynamics on electron transport and well-established relationships between electrical properties, microstructure, and flow. These model suspensions consist of conductive carbon black (CB) particles dispersed in fluids of varying viscosities and dielectric constants. In a stable, well-characterized shear rate regime where all suspensions undergo self-similar agglomerate breakup, competing relationships between conductivity and shear rate were observed. To account for the role of variable agglomerate size, equivalent microstructural states were identified using a dimensionless fluid Mason number, Mn f , which allowed for isolation of the role of dynamics on the flow-induced electron transport rate. At equivalent microstructural states, shear-enhanced particle–particle collisions are found to dominate the electron transport rate. This work rationalizes seemingly contradictory experimental observations in literature concerning the shear-dependent electrical properties of CB suspensions and can be extended to other flowing composite systems.

Science & Technology - Other Topics↗

DOE OSTI2020

Foreword Special issue on the Kilopower Project, Kilowatt Reactor Using Stirling TechnologY (KRUSTY) Test

This special issue of Nuclear Technology contains full-length, peer-reviewed papers describing the design work leading up to and the results of the Kilowatt Reactor Using Stirling TechnologY (KRUSTY) test. KRUSTY was the centerpiece of the National Aeronautics and Space Administration (NASA) Kilopower Project to design, build, and test a space nuclear reactor. This test was the first such test since the end of the Space Nuclear Auxiliary Power (SNAP) project at the end of the 1960s. In this issue, the introduction paper presents the goals of the Kilopower Project and the potential missions this reactor concept could serve in NASA. Kilopower was intended to serve both human exploration needs on planetary surfaces as well as science needs for deep-space exploration. The design work for the experiment by Poston and the power conversion development by Gibson present the pre-work required to perform the eventual KRUSTY test. A paper on regulatory analysis follows, to show the path used to gain approval of the proposed experiment. Then, the early zero-power critical experiments are presented by Sanchez and Grove. These experiments were essential data used to enhance model predictions prior to the high-temperature test. Next, Poston presents the three experiments (warm criticals) that increase the temperature in an incremental fashion prior to the final experiment. These experiments were used to achieve final regulatory approval of the final high-temperature experiment. The last paper by Poston presents the results of the steady-state and transient testing of the reactor at full power and at the design temperature. These results show that the reactor design and as-built experiment met all of the requirements that NASA had developed for the system. Any experiment of this magnitude was accomplished only because of the hard work and dedication of a large number of people at multiple institutions, including the NASA Glenn Research Center, NASA Marshall Space Flight Center, Y-12 National Security Site, Los Alamos National Laboratory, and the Nevada National Security Site prime contractor (formerly National Security Technologies and now the Mission Support and Test Services). The project was jointly funded by the Space Technology Mission Directorate at NASA and the Criticality Safety Program at the National Nuclear Security Administration (NNSA). A special thanks to Jerry McKamy and Angela Chambers at the NNSA and Lee Mason and Don Palac at NASA for their support and guidance. For the authors and multitude of staff that performed this work, the passion for space nuclear reactors was the key to making this experiment a reality.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2021

Description of Paraxiopsis kensleyi n. sp., a new axiid lobster from the Gulf of Mexico (Crustacea: Decapoda: Axiidea)

A new species of axiid was discovered during sampling offshore deep banks on the middle continental shelf off Louisiana. Paraxiopsis kensleyi n. sp. appears to inhabit interstices and cavities of coralline algal rubble, rhodoliths, coral rubble, and other eroded calcareous substrates. Weakly separated from Eutrichocheles Wood-Mason, 1876 on the basis of morphology, present assignments of western Atlantic species to Paraxiopsis de Man, 1905 are regarded as provisional. The new species is described morphologically, and the coloration of freshly captured specimens is documented and compared to related species where possible. Coloration readily distinguishes mature specimens of the new species from Paraxiopsis spinipleura Kensley, 1996, with which it was initially confused. The diagnosis includes GenBank accession numbers for COI sequences to allow future molecular phylogenetic comparisons. Compared to regional species that share a similar dentation or spination on the submedian carina, the pleon of the new species is distinctive in the truncate ventral margin on pleura 2–4, as opposed to being broadly rounded or directed ventrally in an acutely triangular tip. The new species is the eighteenth species of Paraxiopsis worldwide and the ninth from western Atlantic waters, seven of which are now known to range into the Gulf of Mexico. An updated key to western Atlantic members of the genus is provided.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2022

Oppenheimer biographer tours Lab while movie is filmed locally

While a Hollywood movie crew filmed the Oppenheimer movie in Los Alamos these past few weeks, a special guest stopped by the Lab in between takes and chats with big-name actors. Director Thom Mason invited Kai Bird, co-author of American Prometheus: The Triumph and Tragedy of J. Robert Oppenheimer, to LANL while Bird was in town. The film’s director, Christopher Nolan, wrote the screenplay based on Bird’s Pulitzer Prize-winning biography, published in 2005. Oppenheimer was a physicist and the Lab’s first director of its wartime mission to secretly create the atomic bombs and help end World War II.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2022

Operational and Mission Highlights: A Monthly Summary of Top Achievements October 2022

On Sept. 26, Director Thom Mason signed the Laboratory’s annual assessment of four of the weapons systems in our nation’s nuclear stockpile: the B61 family of bombs and the W76, the W78 and the W88 warheads. Addressed to the secretary of energy, the secretary of defense and the chair of the Nuclear Weapons Council, this letter informs the president of the United States of our confidence that the stockpile remains safe, secure, and effective now and into the future as a result of our dedicated sustainment and modernization efforts.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗