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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 37 records · Page 2

Biomanufacturing: history and perspective

Abstract Biomanufacturing is a type of manufacturing that utilizes biological systems (e.g., living microorganisms, resting cells, animal cells, plant cells, tissues, enzymes, or in vitro synthetic (enzymatic) systems) to produce commercially important biomolecules for use in the agricultural, food, material, energy, and pharmaceutical industries. History of biomanufacturing could be classified into the three revolutions in terms of respective product types (mainly), production platforms, and research technologies. Biomanufacturing 1.0 focuses on the production of primary metabolites (e.g., butanol, acetone, ethanol, citric acid) by using mono-culture fermentation; biomanufacturing 2.0 focuses on the production of secondary metabolites (e.g., penicillin, streptomycin) by using a dedicated mutant and aerobic submerged liquid fermentation; and biomanufacturing 3.0 focuses on the production of large-size biomolecules—proteins and enzymes (e.g., erythropoietin, insulin, growth hormone, amylase, DNA polymerase) by using recombinant DNA technology and advanced cell culture. Biomanufacturing 4.0 could focus on new products, for example, human tissues or cells made by regenerative medicine, artificial starch made by in vitro synthetic biosystems, isobutanol fermented by metabolic engineering, and synthetic biology-driven microorganisms, as well as exiting products produced by far better approaches. Biomanufacturing 4.0 would help address some of the most important challenges of humankind, such as food security, energy security and sustainability, water crisis, climate change, health issues, and conflict related to the energy, food, and water nexus.

Zhang, Yi-Heng Percival↗

Cosmic reionization on computers. II. Reionization history and its back-reaction on early galaxies

We compare the results from several sets of cosmological simulations of cosmic reionization, produced under the Cosmic Reionization On Computers project, with existing observational data on the high-redshift Lyα forest and the abundance of Lyα emitters. We find good consistency with the observational measurements and previous simulation work. By virtue of having several independent realizations for each set of numerical parameters, we are able to explore the effect of cosmic variance on observable quantities. One unexpected conclusion we are forced into is that cosmic variance is unusually large at z > 6, with both our simulations and, most likely, observational measurements still not fully converged for even such basic quantities as the average Gunn-Peterson optical depth or the volume-weighted neutral fraction. We also find that reionization has little effect on the early galaxies or on global cosmic star formation history, because galaxies whose gas content is affected by photoionization contain no molecular (i.e., star-forming) gas in the first place. In particular, measurements of the faint end of the galaxy luminosity function by the James Webb Space Telescope are unlikely to provide a useful constraint on reionization.

79 ASTRONOMY AND ASTROPHYSICS↗

History of dark matter

Although dark matter is a central element of modern cosmology, the history of how it became accepted as part of the dominant paradigm is often ignored or condensed into an anecdotal account focused around the work of a few pioneering scientists. The aim of this review is to provide a broader historical perspective on the observational discoveries and the theoretical arguments that led the scientific community to adopt dark matter as an essential part of the standard cosmological model.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Podcast commemorating Black History Month, LANL history Lab Historian talks with member of first Black family to live in Los Alamos

The Lab is commemorating Black History Month with events, stories, and this podcast conversation between Lab Historian Madeline Whitacre and Clayborne Carson Jr.Carson Jr. was a member of what is thought to be the first Black family to live in Los Alamos. He was a young boy when his father, Clayborne Carson Sr., accepted a job with the Atomic Energy Commission (AEC) as a security inspector in December 1947. The Carson family moved to Los Alamos shortly thereafter. Later, as a teenager, Carson Jr. worked at the Lab during the summers.

99 GENERAL AND MISCELLANEOUS↗

Essays on the History of Rocketry and Astronautics: Proceedings of the Third through the Sixth History Symposia of the International Academy of Astronautics, Volume 1

This two volume publication presents the proceedings of the third through sixth history symposia of the International Academy of Astronautics. Thirty-nine papers are divided into four categories: (1) Early Solid Propellant Rocketry; (2) Rocketry and Astronautics: Concepts, Theory, and Analyses after 1880; (3) The Development of Liquid and Solid Propellant Rockets from 1880 to 1945; and (4) Rocketry and Astronautics after 1945. Categories 1 and 2 will be found in volume 1 and the remainder in volume 2. Among other diciplines, Rocketry and Astronautics encompasses the physical and engineering sciences including fluid mechanics, thermodynamics, vibration theory, structural mechanics, and celestial mechanics. Papers presented in these two volumes range from those of empirical experimenters who used the time-honored cut and try methods to scientists wielding theoretical principles. The work traces the coupling of the physical and engineering sciences, industrial advances, and state support that produced the awesome progress in rocketry and astronautics for the most part within living memory. The proceedings of the four symposia present in these two volumes contain information on the work of leading investigators and their associates carried out in the first two-thirds of the twentieth century.

R Cargill Hall↗

Accretion timescale and impact history of Mars deduced from the isotopic systematics of martian meteorites

High precision Sm-Nd isotopic analyses have been completed on a suite of 11 martian basaltic meteorites in order to better constrain the age of silicate differentiation on Mars associated with the formation of their mantle sources. Our data is used to evaluate the merits and disadvantages of various mathematical approaches that have been employed in previous work on this topic. Ages determined from the Sm-Nd isotopic systematics of individual samples are strongly dependent on the assumed Nd isotopic composition of the bulk planet. This assumption is problematic given differences observed between the Nd isotopic composition of Earth and chondritic meteorites and the fact that these materials are both commonly used to represent bulk planetary Nd isotopic compositions. Ages determined from the slope of Sm-146-Nd-142 whole rock isochrons are not dependent on the assumed Nd-142/Nd-144 ratio of the planet, but require the sample suite to be derived from complementary, contemporaneously-formed reservoirs. In this work, we present a mathematical expression that defines the age of formation of the source regions of such a suite of samples that is based solely on the slope of a Nd-143-Nd-142 whole rock isochron and is also independent of any a priori assumptions regarding the bulk isotopic composition of the planet. This expression is also applicable to mineral isochrons and has been used to successfully calculate Nd-143-Nd-142 model crystallization ages of early refractory solids as well as lunar samples. This permits ages to be obtained using only Nd isotopic measurements without the need for Sm-147/Nd-144 isotope dilution determinations. When used in conjunction with high-precision Nd isotopic measurements completed on martian meteorites this expression yields an age of formation of the martian basaltic meteorite source regions of 4504 +/- 6 Ma. Because the Sm-Nd model ages for the formation of martian source regions are commonly interpreted to record the age at which large scale mantle reservoirs formed during planetary differentiation associated with magma ocean solidification, the age determined here implies that magma ocean solidification occurred several tens of millions of years after the beginning of the Solar System. Recent thermal models, however, suggest that Mars-sized bodies cool rapidly in less than similar to 5 Ma after accretion ceases, even in the presence of a thick atmosphere. In assuming these models are correct, an extended period of accretion is necessary to provide a mechanism to keep portions of the martian mantle partially molten until 4504 Ma. Late accretional heating of Mars could either be associated with protracted accretion occurring at a quasi-steady state or alternatively be associated with a late giant impact. If this scenario is correct, then accretion of Mars-sized bodies takes up to 60 Ma and is likely to be contemporaneous with the core formation and possibly the onset of silicate differentiation. This further challenges the concept that isotopic equilibrium is attained during primordial evolution of planets, and may help to account for geochemical evidence implying addition of material into planetary interiors after core formation was completed.

58 GEOSCIENCES↗

A History of Hanford Tank Waste, Implications for Waste Treatment and Disposal

More than 40 years of plutonium processing have left almost 56 million gallons of mixed radioactive waste sequestered in 177 underground tanks on the Hanford Site. Three different processing technologies were employed for plutonium purification in addition to uranium scavenging and fission product removal from the tank waste. All of these chemical processes have contributed to a complex waste stream that varies from tank to tank that presents downstream processing challenges to render the waste into a safe form for long-term storage. The current disposition pathway for Hanford tank waste is vitrification. To maximize waste loading and minimize the number of high-level waste canisters stored in a geologic repository, pretreatment of the waste is required. Both pretreatment and vitrification operations are impacted by the waste composition.

Separations, filtration, ion exchange↗

The Sporadic History of Rubidium and its Role in Corrosion of Steel Related to Nuclear Material Storage

The influence of rubidium (Rb), both in its metallic and oxidized states, on the corrosion resistance of steels has direct relevance to the storage of radioactive Kr-85 containing nuclear materials. Kr-85 undergoes a ß-decay to generate stable, metallic Rb. The literature to date is sparse, contained primarily in company reports and divisive as to whether Rb metal, or its oxides, can lead to corrosion of steel materials. In both the direct storage of Kr-85 and used nuclear fuel that will contain Kr-85, if Rb is corrosive then continual decay of the Kr-85 will generate an increasingly corrosive environment for the steel canister it is stored in. This review was written to consolidate the known data to date on Rb corrosion of steels to identify consistencies, contradictions and remaining gaps in our understanding of the Rb : steel system.

krypton, corrosion, steel, Rubidium↗

History-dependent ion transport through conical nanopipettes and the implications in energy conversion dynamics at nanoscale interfaces

The dynamics of ion transport at nanostructured substrate–solution interfaces play vital roles in high-density energy conversion, stochastic chemical sensing and biosensing, membrane separation, nanofluidics and fundamental nanoelectrochemistry. Advancements in these applications require a fundamental understanding of ion transport at nanoscale interfaces. The understanding of the dynamic or transient transport, and the key physical process involved, is limited, which contrasts sharply with widely studied steady-state ion transport features at atomic and nanometer scale interfaces. Here we report striking time-dependent ion transport characteristics at nanoscale interfaces in current–potential (I–V) measurements and theoretical analyses. First, a unique non-zero I–V cross-point and pinched I–V curves are established as signatures to characterize the dynamics of ion transport through individual conical nanopipettes. Moreoever, ion transport against a concentration gradient is regulated by applied and surface electrical fields. The concept of ion pumping or separation is demonstrated via the selective ion transport against concentration gradients through individual nanopipettes. Third, this dynamic ion transport process under a predefined salinity gradient is discussed in the context of nanoscale energy conversion in supercapacitor type charging–discharging, as well as chemical and electrical energy conversion. Our analysis of the emerging current–potential features establishes the urgently needed physical foundation for energy conversion employing ordered nanostructures. The elucidated mechanism and established methodology can be generalized into broadly-defined nanoporous materials and devices for improved energy, separation and sensing applications.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

EFFECT OF HALO BIAS AND LYMAN LIMIT SYSTEMS ON THE HISTORY OF COSMIC REIONIZATION

We extend the existing analytical model of reionization by Furlanetto et al. to include the biasing of reionization sources and additional absorption by Lyman limit systems. Both effects enhance the original model in non-trivial ways, but do not change its qualitative features. Our model is, by construction, consistent with the observed evolution of the galaxy luminosity function at z {approx}< 8 and with the observed evolution of Ly{alpha} forest at z {approx}< 6. We find that the same model can match the Wilkinson Microwave Anisotropy Probe/Planck constraint on the Thompson optical depth and the South Pole Telescope and EDGES constraints on the duration of reionization for values of the relative escape fraction that are consistent with the observational measurements at lower redshifts. However, such a match is only possible if dwarf galaxies contribute substantially to the ionizing photon budget. The latter condition is inconsistent with simulations and observational upper limits on the escape fraction from dwarfs at z {approx} 3. Whether such a disagreement is due to the different nature of z > 6 galaxies, the inadequacy of simulations and/or some of the observational constraints, or indicates an additional source of ionizing radiation at z > 8 remains to be seen.

79 ASTRONOMY AND ASTROPHYSICS↗