Results for “LABORATORY” — Page 56

NASA NTRS2014

Analytical Techniques for Retrieval of Atmospheric Composition with the Quadrupole Mass Spectrometer of the Sample Analysis at Mars Instrument Suite on Mars Science Laboratory

The Sample Analysis at Mars (SAM) instrument suite is the largest scientific payload on the Mars Science Laboratory (MSL) Curiosity rover, which landed in Mars׳ Gale Crater in August 2012. As a miniature geochemical laboratory, SAM is well-equipped to address multiple aspects of MSL׳s primary science goal, characterizing the potential past or present habitability of Gale Crater. Atmospheric measurements support this goal through compositional investigations relevant to martian climate evolution. SAM instruments include a quadrupole mass spectrometer, a tunable laser spectrometer, and a gas chromatograph that are used to analyze martian atmospheric gases as well as volatiles released by pyrolysis of solid surface materials (Mahaffy et al., 2012). This report presents analytical methods for retrieving the chemical and isotopic composition of Mars׳ atmosphere from measurements obtained with SAM׳s quadrupole mass spectrometer. It provides empirical calibration constants for computing volume mixing ratios of the most abundant atmospheric species and analytical functions to correct for instrument artifacts and to characterize measurement uncertainties. Finally, we discuss differences in volume mixing ratios of the martian atmosphere as determined by SAM (Mahaffy et al., 2013) and Viking (Owen et al., 1977, Oyama and Berdahl, 1977) from an analytical perspective. Although the focus of this paper is atmospheric observations, much of the material concerning corrections for instrumental effects also applies to reduction of data acquired with SAM from analysis of solid samples.

quadropole mass spectometer↗

NASA NTRS2019

Laboratory Astrophysics at NASA Ames: Recent Results and Advances

The Cosmic SImulation Chamber (COSmIC) facility was developed at NASA Ames to study, in the laboratory, neutral and ionized molecules and nanoparticles under the low temperature and high vacuum conditions representative of interstellar, circumstellar and planetary environments. COSmIC is composed of a Pulsed Discharge Nozzle expansion that generates a plasma in a free supersonic jet expansion coupled to highsensitivity, complementary in situ diagnostic tools, used for the detection and characterization of the species present in the expansion: a Cavity Ring Down Spectroscopy and fluorescence spectroscopy systems operating in the UV-Visible range, and a Reflectron Time-Of-Flight Mass Spectrometer (ReTOF-MS). We will present recent advances that were achieved in laboratory astrophysics using COSmIC. These include advances in the domain of the diffuse interstellar bands (DIBs) and in the formation of dust grains and aerosols from their gas-phase molecular precursors in environments as varied as circumstellar outflows and planetary atmospheres. An extension of the spectral response of the facility into the infrared (IR) range is in progress with the addition of a high-resolution near-IR to mid-IR CRDS system that will allow to further investigate cosmic molecules and grains with COSmIC. Acquisition of laser induced fluorescence spectra of cosmic molecule analogs and the laser induced incandescence spectra of cosmic grain analogs are also planned. Preliminary results in these fronts will presented and the implications of the on-going studies for astronomy will be addressed.

Laboratory↗

NASA NTRS2020

The Galactic Cosmic Ray Simulator at the NASA Space Radiation Research Laboratory

With NASA’s new Artemis plan for a sustainable return to the moon, astronauts will once again leave Earth’s protective magnetosphere only to endure higher levels of radiation from galactic cosmic radiation (GCR). The ever penetrating GCR will continue to pose significant health risks especially as lunar missions increase in duration and as NASA sets its aspirations on Mars. The primary risks of concern include carcinogenesis, central nervous system (CNS) effects resulting in potential in-mission cognitive or behavioral impairment and/or late neurological disorders, and degenerative tissue effects including circulatory and heart disease. Characterization and mitigation of these risks requires a significant reduction in the large biological uncertainties of chronic (low-dose rate) heavy ion exposures and the validation of countermeasures in a relevant space environment. Historically, most research on understanding space radiation-induced health risks has been performed using acute exposures of monoenergetic single-ion beams. However, the space radiation environment consists of a wide variety of ion species over a broad energy range. Using the fast beam switching and controls systems technology recently developed at the NASA Space Radiation Laboratory at Brookhaven National Laboratory, a new era in radiobiological research is possible. NASA has developed the “GCR simulator” to generate a spectrum of ion beams that approximates the primary and secondary GCR field experienced at human organ locations within a deep-space vehicle.

NASA Space Radiation Laboratory↗

NASA NTRSDate not supplied

NASA Space Radiation Laboratory Galactic Cosmic Ray Simulator

With exciting new Agency plans for a sustainable return to the moon, astronauts will once again leave earth’s protective magnetosphere only to endure higher levels of radiation from galactic cosmic rays (GCR) and the possibility of a large solar particle event (SPE). Gateway, lunar landers, and surface habitats will be designed to protect crew against SPEs with vehicle optimization, storm shelter concepts, and/or active dosimetry; however, the ever-penetrating GCR will continue to pose the most significant health risks especially as lunar missions increase in duration and as NASA sets its aspirations on Mars. The primary risks of concern include carcinogenesis, central nervous system effects resulting in potential in-mission cognitive or behavioral impairment and/or late neurological disorders, degenerative tissue effects including cataracts, circulatory and heart disease, as well as, potential immune system decrements impacting multiple aspects of crew health. Characterization and mitigation of these risks requires a significant reduction in the large biological uncertainties of chronic (low-dose rate) heavy ion exposures and the validation of countermeasures in a relevant space environment. NASA has developed the “GCR Simulator” at Brookhaven National Laboratory to generate a spectrum of ion beams that approximates the primary and secondary GCR field experienced at human organ locations within a deep-space vehicle. The majority of the dose is delivered from protons (~65-75%) and helium ions (~10-20%) with heavier ions (Z>3) contributing the remainder. The “GCR Simulator” exposes state-of-the art cellular and animal model systems to 33 sequential beams including 4 proton energies plus degrader, 4 helium energies plus degrader, and the five heavy ions of C, O, Si, Ti, and Fe. A polyethylene degrader is used with the 100 MeV/n H and He beams to provide a nearly continuous distribution of low energy particles. A 500 mGy exposure, delivering doses from each of the 33 beams, requires 75-90 minutes. To more closely simulate the low dose rates found in space, sequential field exposures can be divided into daily fractions over 2-6 weeks, with individual beam fractions as low as 0.1-0.2 mGy. In the large beam configuration (60 x 60 cm2), 54 special housing cages can accommodate 2-3 mice each for a 70-75 min duration or ~15 individually housed rats. Emerging research results from our 2018 runs utilizing mixed heavy ion fields and protracted space exposures are forthcoming and will deepen our understanding of the numerous health risks faced by astronauts. This talk discusses NASA’s innovative technology solution for a ground-based GCR simulator at the NASA Space Radiation Laboratory to enable future exploration missions.

galactic cosmic ray simulator↗

NASA NTRS2021

Direct Measurements of Infrared Intensities of HCN and H2O + HCN Ices for Laboratory and Observational Astrochemistry

Hydrogen cyanide (HCN) is found in a wide variety of extraterrestrial environments within and beyond the solar system, and for that reason laboratory spectroscopists have studied this compound in many spectral regions, including the infrared (IR). However, one aspect that remains to be investigated is the intrinsic IR spectral intensities of solid HCN as opposed to relative band strengths, intrinsic intensities being needed to measure HCN abundances. Here we report measurements of IR absorption coefficients and band strengths, along with supporting refractive indices and densities, of both amorphous and crystalline HCN at two temperatures, one for interstellar work and one more relevant to the outer solar system. Spectra are presented at both temperatures, along with optical constants that can be used in numerical models. Despite widespread and longstanding interest in and investigations of solid HCN, this is the first time that the properties we are reporting have been measured in a single laboratory, avoiding the need for estimates or to combine results from various authors. We find that our measured band strength of ~1 × 1017 cm molecule1 for the CN vibration of HCN, in both amorphous HCN and in an H2O-rich ice, is substantially higher than an earlier estimate. Unless errors of 100% can be tolerated then our new value requires a rescaling of earlier work. Our results shed light on why HCN and other nitriles have been so difficult to identify in the solid state, in contrast to their many detections in the gas phase.

astrochemistry – methods: laboratory – solid state↗

NASA NTRS2021

Direct Measurements of Infrared Intensities of HCN and H2O + HCN Ices for Laboratory and Observational Astrochemistry

Hydrogen cyanide (HCN) is found in a wide variety of extraterrestrial environments within and beyond the solar system, and for that reason laboratory spectroscopists have studied this compound in many spectral regions, including the infrared (IR). However, one aspect that remains to be investigated is the intrinsic IR spectral intensities of solid HCN as opposed to relative band strengths, intrinsic intensities being needed to measure HCN abundances. Here we report measurements of IR absorption coefficients and band strengths, along with supporting refractive indices and densities, of both amorphous and crystalline HCN at two temperatures, one for interstellar work and one more relevant to the outer solar system. Spectra are presented at both temperatures, along with optical constants that can be used in numerical models. Despite widespread and longstanding interest in and investigations of solid HCN, this is the first time that the properties we are reporting have been measured in a single laboratory, avoiding the need for estimates or to combine results from various authors. We find that our measured band strength of ~1 × 1017 cm molecule1 for the CN vibration of HCN, in both amorphous HCN and in an H2O-rich ice, is substantially higher than an earlier estimate. Unless errors of 100% can be tolerated then our new value requires a rescaling of earlier work. Our results shed light on why HCN and other nitriles have been so difficult to identify in the solid state, in contrast to their many detections in the gas phase.

astrochemistry – methods: laboratory – solid state↗

NASA NTRS2023

First Optical Constants of Laboratory-Generated Organic Refractory Materials (Tholins) Produced in the NASA Ames COSmIC Facility from the Visible to the Near Infrared (0.4–1.6 μm): Application to Titan’s Aerosols

We have measured the complex refractive indices, from 0.4 to 1.6μm, of five laboratory-generated organic refractory materials (tholins) produced at low temperature(150 K)using plasma chemistry in the stream of a supersonic expansion in NASA Ames’ COsmic SImulation Chamber(COSmIC)facility. Three samples were produced from N2:CH4gas precursors(with different voltages inducing different degrees of ionization in the plasma), one sample was produced from N2:CH4:C2H2, and one sample was produced from Ar:CH4in order to produce a purely carbonaceous sample. The optical constants, n and k, of the samples were determined using spectral reflectance measurements. We observe that both n and k appear to be correlated with the nitrogen content in the solid sample, with samples containing more nitrogen having higher n and k. Comparisons to previous laboratory studies and Titan aerosol optical constants derived from observations show that the COSmIC tholins with a higher nitrogen content (higher n and k)are closer analogs of Titan aerosols. We also present a new analysis of Cassini Visible Infrared Mapping Spectrometer observations of Titan’s atmosphere in the visible to near infrared using the COSmIC tholin optical constants in a radiative transfer model. The COSmIC tholin sample produced from N2:CH4with the lowest energy level has a spectral behavior that appears well suited to reproduce the observed Titan aerosol properties. This study has therefore demonstrated that this COSmIC tholin sample has valuable and promising optical properties for the analysis of Cassini’s Titan atmospheric observations.

Optical Constants↗

DOE OSTI2012

Heat Pump Water Heater Technology Assessment Based on Laboratory Research and Energy Simulation Models: Preprint

This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of US climate regions. Laboratory results demonstrate the efficiency of this technology under most of the conditions tested and show that differences in control schemes and design features impact the performance of the individual units. Theseresults were used to understand current model limitations, and then to bracket the energy savings potential for HPWH technology in various US climate regions. Simulation results show that HPWHs are expected to provide significant energy savings in many climate zones when compared to other types of water heaters (up to 64%, including impact on HVAC systems).

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2014

Evaluating Solar Resource Data Obtained from Multiple Radiometers Deployed at the National Renewable Energy Laboratory: Preprint

Solar radiation resource measurements from radiometers are used to predict and evaluate the performance of photovoltaic and concentrating solar power systems, validate satellite-based models for estimating solar resources, and advance research in solar forecasting and climate change. This study analyzes the performance of various commercially available radiometers used for measuring global horizontal irradiances (GHI) and direct normal irradiances (DNI). These include pyranometers, pyrheliometers, rotating shadowband irradiometers, and a pyranometer with a shading ring deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory (SRRL). The radiometers in this study were deployed for one year (from April 1, 2011, through March 31, 2012) and compared to measurements from radiometers with the lowest values of estimated measurement uncertainties for producing reference GHI and DNI.

14 SOLAR ENERGY↗

DOE OSTI2015

Special Analysis for the Disposal of the Lawrence Livermore National Laboratory EnergyX Macroencapsulated Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) EnergyX Macroencapsulated waste stream (B LAMACRONCAP, Revision 1) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL EnergyX Macroencapsulated waste stream is macroencapsulated mixed waste generated during research laboratory operations and maintenance (LLNL 2015). The LLNL EnergyX Macroencapsulated waste stream required a special analysis due to tritium (3H), cobalt-60 (60Co), cesium-137 (137Cs), and radium-226 (226Ra) exceeding the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015).The results indicate that all performance objectives can be met with disposal of the waste stream in a SLB trench. Addition of the LLNL EnergyX Macroencapsulated inventory slightly increases multiple performance assessment results, with the largest relative increase occurring for the all-pathways annual total effective dose (TED). The maximum mean and 95th percentile 222Rn flux density remain less than the performance objective throughout the compliance period. The LLNL EnergyX Macroencapsulated waste stream is suitable for disposal by SLB at the Area 5 RWMS. The waste stream is recommended for approval without conditions.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2018

AGR-3/4 PIE at Oak Ridge National Laboratory

The Advanced Reactor Technologies (ART) Technology Development Office (TDO) is currently supporting a tristructural isotropic (TRISO) fuel development and qualification program, which includes fuel fabrication, test irradiations, and post-irradiation examination (PIE) and safety testing to assess fuel performance during normal irradiation and under accident conditions. PIE work on fuel from the third and fourth test irradiations, Advanced Gas Reactor-3/4 (AGR-3/4), will begin at Idaho National Laboratory (INL) in approximately April 2015. The work scope in this memorandum purchase order (MPO) includes Oak Ridge National Laboratory (ORNL) providing technical input, developing equipment and techniques for small-area deconsolidation of compacts, and initiating a system design for hot cell operations (expected to begin in about April 2015), and contributing expertise to this effort.