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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 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Mortality among Tennessee Eastman Corporation (TEC) uranium processing workers, 1943–2019

Background: There are few occupational studies of women exposed to ionizing radiation. During World War II, the Tennessee Eastman Corporation (TEC) operated an electromagnetic field separation facility of 1152 calutrons to obtain enriched uranium (235U) used for the Hiroshima atomic bomb. Thousands of women were involved in these operations. Materials and methods: We report a new study was conducted of 13,951 women and 12,699 men employed at TEC between 1943 and 1947 for at least 90 days. Comprehensive dose reconstruction techniques were used to estimate lung doses from the inhalation of uranium dust based on airborne measurements. Vital status through 2018/2019 was obtained from the National Death Index, Social Security Death Index, Tennessee death records and online public record databases. Analyses included standardized mortality ratios (SMRs) and Cox proportional hazards models. Results: Most workers were hourly (77.7%), white (95.6%), born before 1920 (58.3%), worked in dusty environments (57.0%), and had died (94.9%). Vital status was confirmed for 97.4% of the workers. Women were younger than men when first employed: mean ages 25.0 years and 33.0 years, respectively. The estimated mean absorbed dose to the lung was 32.7 mGy (max 1048 mGy) for women and 18.9 mGy (max 501 mGy) for men. The mean dose to thoracic lymph nodes (TLNs) was 127 mGy. Statistically significant SMRs were observed for lung cancer (SMR 1.25; 95% CI 1.19, 1.31; n = 1654), nonmalignant respiratory diseases (NMRDs) (1.23; 95% CI 1.19, 1.28; n = 2585), and cerebrovascular disease (CeVD) (1.13; 95% CI 1.08, 1.18; n = 1945). For lung cancer, the excess relative rate (ERR) at 100 mGy (95% CI) was 0.01 (–0.10, 0.12; n = 652) among women, and –0.15 (–0.38, 0.07; n = 1002) among men based on a preferred model for men with lung doses <300 mGy. NMRD and non-Hodgkin lymphoma were not associated with estimated absorbed dose to the lung or TLN. Conclusions: There was little evidence that radiation increased the risk of lung cancer, suggesting that inhalation of uranium dust and the associated high-LET alpha particle exposure to lung tissue experienced over a few years is less effective in causing lung cancer than other types of exposures. There was no statistically significant difference in the lung cancer risk estimates between men and women. The elevation of certain causes of death such as CeVD is unexplained and will require additional scrutiny of workplace or lifestyle factors given that radiation is an unlikely contributor since only the lung and lymph nodes received appreciable dose.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2024

Simulations of Sparse Static Detector Networks for City-Scale Radiological/Nuclear Detection

Sparse static detector networks in urban environments can be used in efforts to detect illicit radioactive sources, such as stolen nuclear material or radioactive "dirty bombs." We use detailed simulations to evaluate multiple configurations of detector networks and their ability to detect sources moving through a $6\times 6$ km 2 area of downtown Chicago. A detector network's probability of detecting a source increases with detector density but can also be increased with strategic node placement. Here, we show that the ability to fuse correlated data from a source-carrying vehicle passing by multiple detectors can significantly contribute to the overall detection probability. In this article, we distinguish static sensor deployments operated as networks able to correlate signals between sensors, from deployments operated as arrays where each sensor is operated individually. In particular, we show that additional visual attributes of source-carrying vehicles, such as vehicle color and make, can greatly improve the ability of a detector network to detect illicit sources.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2022

Illuminating otoliths: New insights for life history of Balistes triggerfishes

Our understanding of fish life-history strategies is informed by key biological processes, such as growth, survival/mortality, recruitment and sexual maturation, used to characterize fish stocks (populations). Characterizing the life-history traits of fish populations requires the application of accurate age estimation for managed species. Grey triggerfish Balistes capriscus and queen triggerfish Balistes vetula are important reef-associated species for commercial and recreational fisheries in the Atlantic Ocean. Both species exhibit a unique reproductive strategy for large-bodied fisheries-targeted reef fishes in that they are nesting benthic spawners and invest substantial energy in defence and care of their benthic nests and fertilized eggs. Until recently, our understanding of the life-history strategies of triggerfishes assumed the main method used to obtain age estimates, increments counted from thin sections of the first dorsal spine, provided an accurate characterization of population age-based parameters. However, results from bomb radiocarbon validation studies on the two Balistes species demonstrated that spines do not provide accurate ages, but sagittal otoliths do. The main goal of the current study was to provide an updated understanding for triggerfish life-history strategies by using otolith-based age estimates to characterize population age structure and growth for grey triggerfish and queen triggerfish from waters of the south-eastern U.S. Atlantic. The current study is the first to report on sex-specific age and growth information for grey triggerfish using the Δ 14 C-validated otolith-based age estimation method and the results indicate that the previous characterization of Balistes species as exhibiting moderately rapid growth and as relatively short-lived, based on spine-derived age estimates, are flawed. Otolith-based ages indicated that grey triggerfish and queen triggerfish are moderately slow-growing and long-lived species, attaining maximum ages of 21 and 40 years, respectively. Management efforts for triggerfishes should evaluate these new insights and incorporate the results of otolith-based age estimation into future population monitoring efforts.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2024

A comparison of smartphone and infrasound microphone data from a fuel air explosive and a high explosive

For prompt detection of large (>1 kt) above-ground explosions, infrasound microphone networks and arrays are deployed at surveyed locations across the world. Denser regional and local networks are deployed for smaller explosions, however, they are limited in number and are often deployed temporarily for experiments. With the expanded interest in smaller yield explosions targeted at vulnerable areas such as population centers and key infrastructures, the need for more dense microphone networks has increased. An “attritable” (affordable, reusable, and replaceable) and flexible alternative can be provided by smartphone networks. Explosion signals from a fuel air explosive (thermobaric bomb) and a high explosive with trinitrotoluene equivalent yields of 6.35 and 3.63 kg, respectively, were captured on both an infrasound microphone and a network of smartphones. The resulting waveforms were compared in time, frequency, and time-frequency domains. The acoustic waveforms collected on smartphones produced a filtered explosion pulse due to the smartphone's diminishing frequency response at infrasound frequencies (<20 Hz) and was found difficult to be used with explosion characterization methods utilizing waveform features (peak overpressure, impulse, etc.). However, the similarities in time frequency representations and additional sensor inputs are promising for other explosion signal identification and analysis. As an example, a method utilizing the relative acoustic amplitudes for source localization using the smartphone sensor network is presented.

47 OTHER INSTRUMENTATION↗
DOE OSTI2023

False Indications of Dose-Response Nonlinearity in Large Epidemiologic Cancer Radiation Cohort Studies; A Simulation Exercise

This study explores the likely prevalence of false indications of dose-response nonlinearity in large epidemiologic cancer radiation cohort studies (A-bomb survivors, INWORKS, Techa River). Reasons: Increasing numbers of tests of nonlinearity are being made in studies. Hypothesized nonlinear dose-response models have been justified to policy makers by analyses that rely in part on isolated findings that could be statistical fluctuations. After removing dose nonlinearity (linearization) by adjusting person-years of observation at each dose category, indications of nonlinearity, necessarily false, were counted in 5,000 randomized replications of six datasets. The average frequency of any false positive for five indicators of nonlinearity tested against a linear null was roughly 25% in Monte Carlo simulations per study, consistent with binomial calculations, increasing to ~50% within 6 studies assessed. Comparable frequencies were found using Akaike's information criterion (AIC) for model selection or multi-model averaging. False above-zero threshold doses were found more than 50% of the time, averaging to 0.05 Gy, consistent with findings in the 6 studies. Such bias, uncorrected, could distort meta-analyses of multiple studies, because meta-analyses can incorporate high P value findings. AIC-based correction for the extra threshold parameter lowered these false occurrences to 8 to 19%. Given the simulation rates, the possibility of false positives might be noted when isolated findings of nonlinearity are discussed in a regulatory context. When reporting a threshold dose with a P value > 0.05, it would be informative to note the expected high false prevalence rate due to bias.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2022

‘Spokesperson for everyone at the Laboratory who believed in Oppenheimer’ Los Alamos physicist Fred Ribe’s 1954 petition protested former Lab Director’s revoked clearance

In 1953, J. Robert Oppenheimer received an ultimatum. The Atomic Energy Commission (AEC) sent the "father of the atomic bomb" and former Los Alamos Director a letter outlining two options: give up his Q clearance and role as advisor or appear before a board to prove that he wasn’t a threat to national security. Oppenheimer chose the latter. The ensuing saga that unfolded throughout 1954 peaked with a four-week, closed-door hearing in April and May after which Oppenheimer’s security clearance was formally revoked. The long, complex affair consisted of national security concerns, a tangle of questionable charges, divided opinions, loyalties, egos, and vendettas. AEC Chairman Lewis L. Strauss and Oppenheimer were at the center of events, though an important part of the historical record is Fred L. Ribe and the 493 other Los Alamos scientists who risked harming their careers to protest Oppenheimer’s ordeal. Ribe wrote a one-page letter, signed by his colleagues, to President Dwight Eisenhower and the AEC commissioners “objecting the decision and the grounds for it” as Ribe later wrote. This petition – and Strauss’s written response – were donated by Ribe and are part of the unclassified historical collections in the National Security Research Center, which is the Lab’s classified library.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2022

Operation Plumbbob

On June 24, 1957, a thirty-seven kiloton nuclear device, codenamed Priscilla, exploded 700 feet over the Nevada Test Site’s Frenchman dry lake. Below, on the lakebed, was a bank vault designed by the Mosler Safe Company for one of several Federal Civil Defense Administration experiments. The vault was constructed “to evaluate the effectiveness of a reinforced-concrete vault and steel vault door in providing protection against the effects of a nuclear detonation.” Blast damage to the exterior was largely confined to the side walls, whose concrete was stripped off; its steel reinforcing rods bent and twisted. The vault door was essentially undamaged and was opened with minimal difficulty. The vault contents - sandbags, movie camera, and thermometers - were only slightly disturbed. The camera operated as planned, running 40 ft of film. The film, however, was completely fogged. Two clinical type thermometers registered 88°F, and a 24-hr stylus American temperature recorder registered a constant 88°F. Priscilla was the fifth of twenty-nine tests conducted in 1957 as part of Operation Plumbbob, whose stated purpose was to conduct tests “aimed to attain new knowledge important to the defense of the United States and the Free World.” Individual events included “proof tests of air defense and antisubmarine warheads to be stockpiled, development tests of bomb components and mockups, and design tests of smaller and lighter warheads.” One test, John, was that of an air-to-air missile detonated 18,500 feet over the test site.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2022

Operation Redwing

Cherokee exploded with an impressive yield of 3.8 megatons but missed its aiming point by six miles. Although regrettable, the miss was not overly significant because the event proved “that the United States owned a real [thermonuclear] weapon.” Cherokee was the second of seventeen tests conducted during Operation Redwing, whose primary purpose was to proof test bombs and warheads for an emerging generation of weapon systems. Eleven tests took place at Enewetak Atoll and six at Bikini Atoll. The parsing of tests between the two atolls was based largely on expected yields. Lower yield tests were held at Enewetak with the expectation that they would not impact the permanent tests facilities located on the atoll. Higher yield shots were detonated at Bikini. Although this division worked for the most part, fallout from one Bikini test, Tewa, reached Enewetak, contaminating both personnel and permanent test facilities.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2022

How nuclear weapons tests were named

What do Galileo, Husky Pup, Turquoise and Barracuda have in common? They are names of nuclear weapons tests conducted at what is now called the Nevada National Security Site (NNSS). Over 1,000 U.S. nuclear tests were conducted at various sites between 1945 and 1992, and each of the tests was inaugurated with a name, as documented in the Lab’s vast weapons test collections housed in the National Security Research Center (NSRC). To protect the classified information about nuclear weapons and maintain security, nuclear weapons tests were assigned names. This has been true from the beginning with Trinity, the first atomic bomb test in 1945. Lab Director J. Robert Oppenheimer later said the test name may have been inspired by his love of poetry.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2022

Witness the Trinity test through Lab artifacts

July 16 marks the 77th anniversary of the Trinity test, conducted in a desert in New Mexico. The test subject, an atomic bomb called The Gadget, was successfully detonated from a 100-foot steel tower. This event marks the commencement of the Atomic Age, a new era where fission capabilities could be employed for national security purposes. Shortly after the Trinity test, two Los Alamos-created atomic weapons were released above Japan, helping to end the world’s bloodiest conflict just weeks later. “Trinity was one of the greatest scientific experiments ever,” said NSRC Senior Historian Alan Carr said. “Los Alamos scientists changed the world forever on that day. Not only was it the dawn of the Atomic Age, but also the beginning of the Lab’s eight decades of cutting-edge science and its national security charge.” To preserve this event, and to continue to learn more about this critical moment in history, the National Security Research Center (NSRC) curates a collection of photographs, films, notes, unclassified artifacts and numerous other materials related to the science of the test. Notably, the collection includes a novel material that formed at the site, trinitite, and artifacts from one of the intriguing scientists present at the test, Enrico Fermi.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2022

A Partnership between countries that endures today. The British Mission was a part of the Lab from 1943-1945

After 27 months of grueling hours and scientific secrecy amidst the pressure of a mounting death toll and Nazi Germany's own weapons development, it had come to an end. It was time to celebrate. On September 22, 1945, scientists, engineers and their families gathered at Fuller Lodge downtown to celebrate the success of the Los Alamos atomic bomb and the end of World War II. The party was hosted by members of the British Mission and their wives and included food, dancing and a satirical play based on the lighter moments of wartime life in Los Alamos. However, this party was more than just entertainment and a night of festivities, it also represented a partnership between countries that endures today.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2022

Evaluation of Strain and Exhaustion Limits for Vessels

Design rules for impulsively loaded vessels (ILVs) have been incorporated in Section VIII, Division 3 of the ASME Code since 2019, based upon earlier development of ASME Code Case 2564. These rules are particularly applicable to explosive containment vessels (ECVs) used to fully or partially contain the combustion products of explosives. Uses of these ECVs include containment of suspect luggage at airports, bomb disposal, containment of experiments on explosive devices, and destruction of chemical munitions.

36 MATERIALS SCIENCE↗
DOE OSTI2022

The Influence of Environment on Post-Detonation Chemistry and Debris Formation (Abbreviated Final Report: 20-SI-006)

Predicting, responding to, or interpreting the chemical record preserved in debris derived from nuclear events can be challenging due to chemical fractionation. Chemical fractionation is where different species of the evolving radionuclide inventory segregate and/or are lost from the system over the timescales of debris formation. Both historic data and recent research suggest that the interaction and character of the local environment may exert controls on chemical fractionation by influencing the cooling and evolution of the associated fireball as well as the composition of the vapor term and resultant speciation. Prior to this work, an integrated platform permitting dynamic and concurrent consideration of physical and chemical evolution of early time post-detonation event environments did not exist. Our work merged historic data and experimental approaches to support development of a computational framework able to simulate fundamental processes (e.g., entrainment of local environment, oxidation chemistry, and cooling time scales) that may perturb the radionuclide inventory captured in post-detonation debris. Work with historic debris confirmed that entrained environmental material affect debris composition, structure, and radionuclide incorporation. Complementary work utilizing a readily controllable and tunable benchtop setup (a plasma flow reactor) simulated the late cooling of a nuclear fireball (e.g., T < 6000 K) and bounded the sensitivity of actinide speciation and particle size distribution to variations in oxygen concentration and cooling rates. Concurrent laser ablation and laser heating experiments were used to investigate the chemistry and physics of processes occurring in vaporized and/or rapidly heated actinides and other elements in the presence of oxygen. A more computationally efficient microphysical model was developed for predicting and evolving size distributions of particles forming from mixed vapor terms and simulating particle formation processes under a variety of extreme conditions. Continued study of historic nuclear event film confirmed that shockwave data and physics codes agree to within the uncertainty of the data. Good agreement was achieved for thermal emission from an airburst, however the paucity of low-temperature molecular opacity data for mixtures of air, bomb debris, entrained dirt, and water vapor complicate agreement for more elaborate scenarios. A multiphysics code (ALE3D) was modified to bring the necessary physics and chemistry, including these new data and insights, onto a single platform. Code development included improved initialization of large physical systems, modernization of chemistry capabilities, and modifications to enable inclusion of particle transport.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2022

From print to digital: Preserving over 10,000 McKibbin Cards

Collections management staff from the National Security Research Center (NSRC) recently digitized more than 10,000 McKibbin Cards to make them accessible on the Lab’s unclassified network, said NSRC collections management team leader Patricia Cote (WRS-NSRCMS). The cards, named after Dorothy McKibbin, who was known as the gatekeeper of Los Alamos because she was often the first point of contact for new hires, have become symbolic of the Lab when the world’s greatest minds secretly gathered to create the first atomic bomb and end World War II.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2022

Experimental Set-up for the Study of Chemical Fractionation and Aerosol Dynamics

Experimental investigations of chemical fractionation/phase partition and aerosol dynamics in high-temperature environment were reviewed and discussed. Particle composition and size distribution are the key data for aerosol dynamics predictive model and simulation. However, there were no particle size distribution available from the previous works. Nucleation, condensation, and coagulation are three key physical processes driving the fractionation or phase partition thereby the aerosol dynamics. A new approach was proposed to experimentally observe fractionation/phase partition and provide data for validating the predictive model for aerosol dynamics in the simulation of bomb debris formation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
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↗
DOE OSTI2022

Identification of Material Type and Thickness Using Combined X-ray and Fast Neutron Radiography

Material identification (ID) using radiography is a problem that has implicitly existed since the discovery of the X-ray. Since 9-11, this problem has received renewed attention for homeland security applications of the generic, “what is in the box?” type1. Examples of items potentially in the box include: roadside bombs, nuclear weapons, contraband shipments and the like. In these cases, the “what” can include: explosives, projectiles, fissile material, or drugs. Here we investigate the ability of 60Co gamma-rays, 14MeV neutrons, and their combination to tease apart information about density, thickness and atomic number of items in the box. That information subset can be combined with other types of independent information (e.g. neutron and gammaspectroscopy, intelligence, photographs etc.) to assert a more complete picture of what, exactly, is in the box? That more complete information set can form the basis for actions including: remote detonation, evacuations, disablement, detention, search, arrest etc.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Nuclear Testing and the Joint Task Force System

During the 1940s, 50s, and early 60s, the United States conducted eight nuclear test operations in the far reaches of the Pacific Ocean. These operations were possible only because of a military command and control organization, the joint task force. Commanded by the Army Navy, and Air Force on a rotating basis, each of the seven JTFs provided the means by which the thousands of ships, planes, material, and personnel were moved over thousands of miles of ocean. The first task force, JTF-1, was created to test the destructive effects of the Fat Man bomb on Naval vessels at Bikini Atoll in the summer of 1946. Commanded by Vice Admiral William “Spike” Blandy, JTF-1 was a purely military operation supported by the MED. Never meant to be a permanent organization, JTF-1 was dissolved soon after completing its mission.

99 GENERAL AND MISCELLANEOUS↗