Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “nevada”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 883 records · Page 49
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Measurement of Wind Loading on Heliostats at the Crescent Dunes Power Plant: An Overview

The cost of solar collectors constitutes almost one third of the total cost of a CSP plant. One of the ongoing challenges in the design of these collectors is wind loading on mirrors, support structures, and drives. A particular challenge is dynamic wind loading, caused by the turbulent wind flow. To date, the design of solar collector structures has relied on wind tunnel experiments and numerical simulations that do not entirely capture the dynamic effects observed at scale. The CSP industry has shown increased interest in validating the idealized assumptions with measurements obtained in operational settings to improve wind load assumptions and increase reliability and cost-efficiency of the collector design. Further, performance models need realistic assumptions about wind loading and its impact on optical performance. In a parabolic trough field campaign, NREL successfully collected a wealth of long-term, high-resolution wind and loads data [2], that are publicly available and that can be used for the above-mentioned purposes. Heliostats are impacted differently by wind than parabolic troughs, due to their different shape, size, and field layout. To study the impact of wind and turbulence on heliostats, we initiated another field campaign in an operational power- tower plant, Crescent Dunes, in Nevada, USA. In this work, we present an overview of the measurements, first results, and potential implications of wind driven loads on Heliostats.

concentrated solar power↗
DOE OSTI2025

2024-03U-JWS01 - Initial Abstract

Abstract for recently approved CRADA joint work statement 2024-03U-JWS01 with University of Nevada Reno. Publication of abstract at time of approval satisfies requirements of DOE O 483.1B.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2025

High‐Speed Embedded Ink Writing of Anatomic‐Size Organ Constructs

Embedded ink writing (EIW) is an emerging 3D printing technique that fabricates complex 3D structures from various biomaterial inks but is limited to a printing speed of ∼10 mm s −1 due to suboptimal rheological properties of particulate-dominated yield-stress fluids when used as liquid baths. In this work, a particle-hydrogel interactive system to design advanced baths with enhanced yield stress and extended thixotropic response time for realizing high-speed EIW is developed. In this system, the interactions between particle additive and three representative polymeric hydrogels enable the resulting nanocomposites to demonstrate different rheological behaviors. Accordingly, the interaction models for the nanocomposites are established, which are subsequently validated by macroscale rheological measurements and advanced microstructure characterization techniques. Filament formation mechanisms in the particle-hydrogel interactive baths are comprehensively investigated at high printing speeds. To demonstrate the effectiveness of the proposed high-speed EIW method, an anatomic-size human kidney construct is successfully printed at 110 mm s −1 , which only takes ∼4 h. This work breaks the printing speed barrier in current EIW and propels the maximum printing speed by at least 10 times, providing an efficient and promising solution for organ reconstruction in the future.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Nitrogen fixation in Pampinifervens , a new species-rich genus of Aquificaceae that inhabits a wide pH range in terrestrial hot springs

Members of the Aquificota play important roles in hydrogen, sulfur, and carbon cycles in geothermal systems as ubiquitous and abundant chemolithoautotrophs; however, their roles in the nitrogen cycle are poorly defined. Here, we show that Aquificaceae isolate T-2 T from Tengchong, China, fixes nitrogen based on growth with dinitrogen as the sole nitrogen source and incorporation of 15 N atoms when grown with 15 N 2 . We further show evidence that suggests its nitrogen fixation (nif) genes are transcribed in situ in a nearby spring. We propose the name Pampinifervens diazotrophicum gen. et sp. nov., with strain T-2 T (= JCM 35475 T = DSM 116324 T ) as the nomenclatural type. Its close relative designated Pampinifervens florentissimum sp. nov. T-8 T (= CGMC 1.5214 T = JCM 33569 T ) does not fix nitrogen but respires nitrate. Analysis of 104 metagenome-assembled genomes from 84 metagenomes allowed us to circumscribe the genus Pampinifervens and identify at least 16 sympatric Pampinifervens species that dominate the Aquificaceae populations in diverse hot springs in southwest China, with distinct species globally. Analysis of these Pampinifervens genomes revealed variable presence of nif and denitrification genes and frequent gene loss and horizontal transfer. Genes for pH homeostasis were also present in Pampinifervens genomes, with a proliferation in species from Tengchong, consistent with the wide pH growth range of both Pampinifervens isolates and the prevalence of Pampinifervens in both alkaline and acidic springs. The dynamic evolution of nif and denitrification genes, along with pH homeostasis genes, may facilitate the diversification of Pampinifervens into diverse springs with different nitrogen availability.

Aquificae↗
DOE OSTI2026

Electron-ion equilibration in superheated gold

Electron-ion equilibration dynamics in samples driven into superheated states with multi-eV electron temperatures represent a fundamental process in nonequilibrium physics. A clear picture of the evolving ion temperature is essential for understanding the strength of the electron-ion coupling. However, direct, model-independent measurements of the ion temperature in laser-irradiated samples have remained experimentally elusive. Using inelastic X-ray scattering with meV-resolution in gold samples, the ion response to ultrafast heating by the hot electrons can be resolved, quantifying the electron-ion equilibration dynamics. We report measurements revealing a strongly enhanced energy transfer rate compared to that in weakly excited gold. Moreover, we obtain a quasi-constant electron-ion coupling at the highly elevated electron temperatures. These results place new constraints on electron-ion energy transfer in warm dense matter and establish a path toward quantitative benchmarking of models for nonequilibrium dynamics.

Griffin, Travis D. [Univ. of Nevada, Reno, NV (Uni↗
DOE OSTI2024

Highly Active Carbon–Platinum-Based Nanozymes: Synthesis, Characterization, and Immunoassay Application

Nanozymes (nanomaterials with intrinsic enzyme-like characteristics) have gained much attention for diagnostics and therapy due to their excellent enzyme-mimicking capability, great stability in environments, and facile and low-cost production. However, developing nanozymes with a high catalytic constant, K cat , has been challenging. Herein, we report a class of nanozyme-mimicking peroxidases, which are formed by depositing ultrasmall platinum nanoparticles (Pt NPs) 1–2 nm in size on the surface of hydrophilic nitrogen-doped carbon nanoparticles (CN NPs). These nanozymes defined as CN-Pt NPs show a high peroxidase-like activity with K cat values of 1.27 M·mL/s·g for 3,3,5,5′-tetramethylbenzidine (TMB) and 1.97 M·mL/s·g for hydrogen peroxide (H 2 O 2 ), respectively, which are at least one or two orders higher than many other reported carbon–noble metal-based nanozymes. Our developed CN-Pt NPs were further utilized in a colorimetric immunoassay as signal amplifiers for the biomarker detection of Burkholderia pseudomallei, a Gram-negative bacterial pathogen classified as a tier 1 select agent by the US CDC. In conclusion, the assay achieved lower limits of detection of 0.11 ng/mL in phosphate-buffered saline (PBS) and 0.16 ng/mL in human serum, when compared to many other assays in detecting the same biomarker.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Superheating gold beyond the predicted entropy catastrophe threshold

In their landmark study, Fecht and Johnson unveiled a phenomenon that they termed the ‘entropy catastrophe’, a critical point where the entropy of superheated crystals equates to that of their liquid counterparts. This point marks the uppermost stability boundary for solids at temperatures typically around three times their melting point. Despite the theoretical prediction of this ultimate stability threshold, its practical exploration has been prevented by numerous intermediate destabilizing events, colloquially known as a hierarchy of catastrophes, which occur at far lower temperatures. Here we experimentally test this limit under ultrafast heating conditions, directly tracking the lattice temperature by using high-resolution inelastic X-ray scattering. Our gold samples are heated to temperatures over 14 times their melting point while retaining their crystalline structure, far surpassing the predicted threshold and suggesting a substantially higher or potentially no limit for superheating. We point to the inability of our samples to expand on these very short timescales as an important difference from previous estimates. These observations provide insights into the dynamics of melting under extreme conditions.

Laser-produced plasmas↗
DOE OSTI2025

Feasibility of carbon foam-based sorbents for the abatement of gaseous mercury and iodine

The U.S. Department of Energy Hanford Site in Washington State is in the process of commissioning the Waste Treatment and Immobilization Plant to process a portion of the 54 million gallons of radioactive and chemical waste from cold war weapon production. Technologies for the capture of volatile species of concern are still being assessed, and new methods and materials are developed as operational and flowsheet mission risks are identified. One such area still being assessed is the abatement efficacy of the Carbon Adsorber units to retain gaseous mercury and 129 I released during processing. It is challenging to predict the mercury chemistry due to the variability of the feed, and different methods/materials are required for the capture of gaseous Hg 0 and Hg II compounds. In this study, the feasibility of using developmental carbon foam (CF) sorbents for the capture of iodine and mercury was assessed using static and dynamic flow testing and compared against a commercially available sorbent, BATII-37. Both CF and CF functionalized with bismuth particles (CF-Bi) chemisorbed iodine, and CF-Bi had similar mercury capture performance to BATII-37 in dynamic flow tests. While species loading concentrations were measurable, limitations in achieving a mass balance prevented a full evaluation of capture efficacy. Nonetheless, the results serve as an important first step in demonstrating the potential for simultaneous iodine and mercury capture.

Hanford site↗