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At least 451 records · Page 25
All sourcesNASA NTRSDOE OSTI
NASA NTRS2001

Assessment of Air Quality in the Shuttle and International Space Station (ISS) Based on Samples Returned by STS-100 at the Conclusion of 6A

The toxicological assessment of air samples returned at the end of the STS-100 (6A) flight to the ISS is reported. ISS air samples were taken in March and April 2001 from the Service Module, FGB, and U.S. Laboratory using grab sample canisters (GSCs) and/or formaldehyde badges. An unplanned "first-entry" sample of the MPLM2 (multipurpose logistics module) atmosphere was taken with a GSC, and preflight and end-of-mission samples were obtained from Endeavour using GSCs. Analytical methods have not changed from earlier reports, and all quality control measures were met for the data presented herein. The two general criteria used to assess air quality are the total-non-methane-volatile organic hydrocarbons (NMVOCs) and the total T-value (minus the CO2 and formaldehyde contribution). Because of the Freon 218 (octafluoropropane, OFP) leak, its contribution to the NMVOC is indicated in brackets. When comparing the NMVOC values with the 25 mg/cubic m guideline, the OFP contributions should be subtracted. Control of atmospheric alcohols is important to the water recovery system engineers, hence total alcohols were also assessed in each sample.

James, John T.↗
NASA NTRS2001

Assessment of Air Quality in the Shuttle and International Space Station (ISS) Based on Samples Returned by STS-105 at the Conclusion of 7A.1

The toxicological assessment of air samples returned at the end of the STS-105 (7 A.1) flight to the ISS is reported. ISS air samples were taken in August 2001 from the Service Module, FGB, and U.S. Laboratory using grab sample canisters (GSCs) and/or formaldehyde badges. Preflight and end-of-mission samples were obtained from Discovery using GSCs. Analytical methods have not changed from earlier reports, and surrogate standard recoveries were 64-115%. Pressure tracking indicated no leaks in the canisters.

James, John T.↗
NASA NTRS2010

Eight Year Climatologies from Observational (AIRS) and Model (MERRA) Data

We examine climatologies derived from eight years of temperature, water vapor, cloud, and trace gas observations made by the Atmospheric Infrared Sounder (AIRS) instrument flying on the Aqua satellite and compare them to similar climatologies constructed with data from a global assimilation model, the Modern Era Retrospective-Analysis for Research and Applications (MERRA). We use the AIRS climatologies to examine anomalies and trends in the AIRS data record. Since sampling can be an issue for infrared satellites in low earth orbit, we also use the MERRA data to examine the AIRS sampling biases. By sampling the MERRA data at the AIRS space-time locations both with and without the AIRS quality control we estimate the sampling bias of the AIRS climatology and the atmospheric conditions where AIRS has a lower sampling rate. While the AIRS temperature and water vapor sampling biases are small at low latitudes, they can be more than a few degrees in temperature or 10 percent in water vapor at higher latitudes. The largest sampling biases are over desert. The AIRS and MERRA data are available from the Goddard Earth Sciences Data and Information Services Center (GES DISC). The AIRS climatologies we used are available for analysis with the GIOVANNI data exploration tool. (see, http://disc.gsfc.nasa.gov).

Hearty, Thomas↗
DOE OSTI2026

Elemental analysis of air-sensitive frozen molten salt samples using an inert transfer chamber for LIBS/LA-ICP-TOF-MS analysis

A novel inert sample transfer system was developed and employed to enable, for the first time, the analysis of air-sensitive salt samples in a two-volume ablation cell using simultaneous laser-induced breakdown spectroscopy (LIBS) and laser ablation (LA)-inductively coupled plasma (ICP)-time-of-flight (TOF)-mass spectrometry (MS) analysis. Molten salts are of growing interest as a medium for advanced nuclear reactors and nuclear fuel reprocessing technologies continue to be developed around their use. However, compositional analysis of molten salt samples can be challenging because of their air-sensitive nature and varying solubilities leading to inaccurate measurements when digested. LA-based analysis provides an alternate method to digestion and can provide rapid elemental information with little sample preparation. In this study, LIBS and LA-ICP-TOF-MS were used to analyze the Ce content in frozen salt samples taken from a series of electrochemical experiments. Calibrations were built for each technique, and the resulting limits of detection for Ce were estimated to be 107 and 58 µg g −1 for LIBS and LA-ICP-TOF-MS, respectively. Test samples from the electrochemical experiments were analyzed using these calibrations. The results matched bulk digestion-based ICP-optical emission spectroscopy values, and daily trends in Ce concentration changes were identified. Additionally, the LIBS and LA-ICP-TOF-MS analysis was demonstrated for identifying microgram per gram levels of components and detecting trace contaminants. The impurities detected by LIBS included Al, Mg, Ca, and Na. The impurities detected by LA-ICP-TOF-MS included W, Ag, Al, Fe, Ni, Mo, Nd, Sm, Th, and U.

Andrews, Hunter B. [Oak Ridge National Laboratory ↗
NASA NTRS1986

Solid-Sorbent Air Sampler

Portable unit takes eight 24-hour samples. Volatile organic compounds in air collected for analysis by portable, self-contained sampling apparatus. Sampled air drawn through sorbent material, commercial porous polymer of 2, 3-diphenyl-p-phenylene oxide. High-boiling-point organic compounds adsorbed onto polymer, while low-boiling-point organics pass through and returned to atmosphere. Sampler includes eight sample tubes filled with polymeric sorbent. Organic compounds in atmosphere absorbed when air pumped through sorbent. Designed for checking air in spacecraft, sampler adaptable to other applications as leak detection, gas-mixture analysis, and ambient-air monitoring.

Galen, T. J.↗
DOE OSTI2012

Magnetocaloric effect in manganites

The magnetocaloric effect (MCE) in La{sub 1-x}Sr{sub x}MnO{sub 3}, Sm{sub 0.55}Sr{sub 0.45}MnO{sub 3}, and PrBaMn{sub 2}O{sub 6} compounds is studied. The maximum values of MCE ({Delta}T{sub max}) determined by a direct method in the second and third compositions and in La{sub 0.9}Sr{sub 0.1}MnO{sub 3} are found to be much lower than those calculated from the change of the magnetic part of entropy in the Curie temperature (T{sub C}) and the Neel temperature (T{sub N}) range. The negative contribution of the antiferromagnetic (AFM) part of a sample in the La{sub 1-x}Sr{sub x}MnO{sub 3} system at 0.1 {<=} x {<=} 0.3 decreases {Delta}T{sub max} and changes the {Delta}T(T) curve shape, shifting its maximum 20-40 K above T{sub C}. Lower values of {Delta}T{sub max} are detected in the range T{sub C} = 130-142 K in polycrystalline and single-crystal Sm{sub 0.55}Sr{sub 0.45}MnO{sub 3} samples cooled in air. If such samples were cooled in an oxygen atmosphere (which restores broken Mn-O-Mn bonds and, thus, increases the volume of CE-type AFM clusters), the maximum in the temperature dependence of MCE is located at T{sub N} (243 K) for CE-type AFM clusters. A magnetic field applied to a sample during the MCE measurements transforms these clusters into a ferromagnetic (FM) state, and both types of clusters decompose at T = T{sub N}. The PrBaMn{sub 2}O{sub 6} composition undergoes an AFM-FM transition at 231 K, and the temperature dependence of its MCE has a sharp minimum at T = 234 K, where MCE is negative, and a broad maximum covering T{sub C}. The absolute values of MCE at both extrema are several times lower than those calculated from the change in the magnetic entropy. These phenomena are explained by the presence of a magnetically heterogeneous FM-AFM state in these manganites.

36 MATERIALS SCIENCE↗
NASA NTRSDate not supplied

Continued Environmental Microbiology Monitoring of The International Space Station (ISS) Veggie Unit Used for In-Flight, Crop-Based Food Systems

The International Space Station is a closed environment where rotating sets of Crewmembers live and work. This environment is monitored to ensure occupants’ health and safety during their spaceflight residency by routine Environmental Health System (EHS) collection of microbial samples including air, surface, and water. The microbial samples are collected, enumerated, and analyzed quarterly to monitor on-board system contamination and potential risks to crew health. Quarterly monitoring of the microorganisms in the ISS environment supports crew safety and contributes to a large set of microbial concentration and diversity data. The current in-inflight microbial requirements were developed using this historical data collected by the routine environmental monitoring. These in-flight microbial requirements have been established to maintain the health and safety of the spacecraft environment. This study leverages quarterly operational EHS sampling by collecting additional microbial samples from the surface of the Veggie plant production system on ISS. These samples will yield microbial concentration and diversity that can be compared and analyzed with nominal surface samples from the vehicle. The data collected in this study will aid in the development of requirements for spaceflight-based food production systems. Continued surface sampling of the internal and external surfaces of the Veggie system, along with collaboration from both Johnson Space Center (JSC) & Kennedy Space Center (KSC) scientists studying the microbiome of the veggie-crop systems, will be implemented as part of the future development of crop-based food system requirements for the ISS and beyond.

Christian Mena↗
DOE OSTI2019

Novel rapid oxidizing fusion method to determine Polonium-210 in air filters

A rapid method for the determination of polonium-210 in air filters has been created for use following a radiological event and for routine environmental monitoring. Air filter samples, including cellulose and glass fiber, are fused with a sodium or potassium nitrate/sodium hydroxide flux material. The alkaline matrix minimizes polonium volatility during sample digestion steps, while efficiently dissolving the air filter and inorganic matter implanted on the filter. The addition of nitrate to the flux destroys organic material which can decrease Polonium recovery during precipitation, extraction and source preparation steps. Polonium is concentrated and separated from the sample matrix using an iron hydroxide precipitation and extraction chromatography with DGA Resin. Polonium-210 is subsequently measured by alpha spectrometry following rapid microprecipitation with bismuth phosphate. The new method employs extraction chromatographic purification to remove alpha emitting interferences and sample matrix constituents which can interfere with 210 Po measurements using alpha spectrometry. The novel blend of sodium hydroxide and alkali metal nitrate digests the air filters quickly and effectively.

61 RADIATION PROTECTION AND DOSIMETRY↗
NASA NTRS1994

Enhancement of acidic gases in biomass burning impacted air masses over Canada

Biomass-burning impacted air masses sampled over central and eastern Canada during the summer of 1990 as part of ABLE 3B contained enhanced mixing ratios of gaseous HNO3, HCOOH, CH3COOH, and what appears to be (COOH)2. These aircraft-based samples were collected from a variety of fresh burning plumes and more aged haze layers from different source regions. Values of the enhancement factor, delta X/delta CO, where X represents an acidic gas, for combustion-impacted air masses sampled both near and farther away from the fires, were relatively uniform. However, comparison of carboxylic acid emission ratios measured in laboratory fires to field plume enhancement factors indicates significant in-plume production of HCOOH. Biomass-burning appears to be an important source of HNO3, HCOOH, and CH3COOH to the troposphere over subarctic Canada.

Lefer, B. L.↗
NASA NTRS1988

Development of remote sensing techniques capable of delineating soils as an aid to soil survey

Eighty-one benchmark soils from Alabama, Georgia, Florida, Tennessee, and Mississippi were evaluated to determine the feasibility of spectrally differentiating among soil categories. Relationships among spectral properties that occur between soils and within soils were examined, using discriminant analysis. Soil spectral data were obtained from air-dried samples using an Exotech Model 20C field spectroradiometer (0.37 to 2.36 microns). Differentiating among the orders, suborders, great groups, and subgroups using reflectance spectra achieved varying percentages of accuracy. Six distinct reflectance curve forms were developed from the air-dried samples based on the shape and presence or absence of adsorption bands. Iron oxide and organic matter content were the dominant soil parameters affecting the spectral characteristics for differentiating among and between these soils.

Coleman, T. L.↗
DOE OSTI2019

Modification of the Surface Properties of PbSnTe〈In〉 Epitaxial Layers with Composition near Band Inversion

High-resistance Pb{sub 1 –x}Sn{sub x}Te〈In〉 layers grown by molecular beam epitaxy on BaF{sub 2}(111) substrates with compositions close to band inversion have been investigated. The I–V characteristics and relaxation dependences of the photocurrent of the structures in dependence on the chemical surface treatment and subsequent exposure of the samples in air have been examined. It has been observed that the characteristics significantly transform depending on the physicochemical surface state. It has been found that the chemical surface treatment in the hydrochloric acid solution in isopropyl alcohol leads to an increase in the current by up to four orders of magnitude with the subsequent recovery of the I–V characteristics upon exposure of the samples in air for several days.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
NASA NTRS2012

Whole Module Offgas Test Report: Space-Xl Dragon Module

On September 26 and September 28,2012 a chemist from the JSC Toxicology Group acquired samples of air in 500 m1 evacuated canisters from the sealed Space-Xl Dragon Module. One sample was also acquired from Space-X Facility near the module at the start of the test. Samples of the module air were taken in triplicate once the module had been sealed, and then taken again in triplicate 1.98 days later. Ofthe triplicate samples, the first served as a line purge, and the last two were analyzed. The results of 5 samples are reported.

James, John T.↗
DOE OSTI2012

Analysis of Vapors from Methylene Chloride Extracts of Nuclear Grade Hepa Filter Fiberglass Samples (Rev.1)

While several organic compounds were detected in the vapor samples used in the reenactment of the preparation of mounts from the extracts of nuclear grade high-efficiency particulate air filter fiberglass samples, the most significant species present in the samples were methylene chloride, phenol, phenol-d6, and 2-fluorophenol. These species were all known to be present in the extracts, but were expected to have evaporated during the preparation of the mounts, as the mounts appeared to be dry before any vapor was collected. These species were present at the following percentages of their respective occupational exposure limits: methylene chloride, 2%; phenol, 0.4%; and phenol-d6, 0.6%. However, there is no established limit for 2-fluorophenol. Several other compounds were detected at low levels for which, as in the case of 2-fluorophenol, there are no established permissible exposure limits. These compounds include 2-chlorophenol; N-nitroso-1-propanamine; 2-fluoro-1,1'-biphenyl; 1,2-dihydroacenaphthylene; 2,5-cyclohexadiene-1,4-dione,2,6-bis(1,1-dimethylethyl); trimethyl oxirane; n-propylpropanamine; 2-(Propylamino)ethanol; 4-methoxy-1-butene; 6-methyl-5-hepten-2-one; and 3,4-dimethylpyridine. Some of these were among those added as surrogates or spike standards as part of the Advanced Technologies and Laboratories International, Inc. preparation of the extract of the HEPA filter media and are indicated as such in the data tables in Section 2, Results; other compounds found were not previously known to be present. The main inorganic species detected (sulfate, sodium, and sulfur) are also consistent with species added in the preparation of the methylene chloride extract of the high-efficiency particulate air sample.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2011

EMP Attachment 1: DOE-SC PNNL Site Sampling and Analysis Plan

This Sampling and Analysis Plan (SAP) is written for the radiological environmental air surveillance program for the DOE-SC PNNL Site, Richland Washington. It provides the requirements for planning sampling events, and the requirements imposed on the analytical laboratory analyzing the air samples. The actual air sampling process is in procedure EPRP-AIR-029. The rationale for analyte selection, media, and sampling site location has been vetted through the data quality objectives (DQO) process (Barnett et al. 2010). The results from the DQO process have been reviewed and approved by the Washington State Department of Health. The DQO process (Barnett et al. 2010) identified seven specific radionuclides for analysis along with the need for gross alpha and gross beta radiological analyses. The analytes are 241<\sup>Am, 243<\sup>Am, 244<\sup>Cm, 60<\sup>Co, 238<\sup>Pu, 239<\sup>Pu, and 233<\sup>U. The report also determined that air samples for particulates are the only sample matrix required for the monitoring program. These samples are collected on 47-mm glass-fiber filters.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2014

Gas cell for in situ soft X-ray transmission-absorption spectroscopy of materials

A simple gas cell design, constructed primarily from commercially available components, enables in situ soft X-ray transmission-absorption spectroscopy of materials in contact with gas at ambient temperature. The cell has a minimum X-ray path length of 1 mm and can hold gas pressures up to ~300 Torr, and could support higher pressures with simple modifications. The design enables cycling between vacuum and gas environments without interrupting the X-ray beam, and can be fully sealed to allow for measurements of air-sensitive samples. The cell can attach to the downstream port of any appropriate synchrotron beamline, and offers a robust and versatile method for in situ measurements of certain materials. The construction and operation of the cell are discussed, as well as sample preparation and proper spectral analysis, illustrated by examples of spectral measurements. Potential areas for improvement and modification for specialized applications are also mentioned.

47 OTHER INSTRUMENTATION↗
DOE OSTI2022

Modeling the use of mobile modular gas samplers in near-field detection

The Wireless Independent Noble Gas Sampler (WINGS) is a mobile, modular gas sampling system designed for use in low infrastructure environments. In the case of a suspected underground nuclear explosion (UNE), WINGS units could be deployed to detect noble gases emanating from the suspected explosion site or identify gases originating from another source entering the local area from offsite. In conclusion, this work uses the atmospheric transport modeling tool inline WRF-HYSPLIT to test the effectiveness of WINGS units around a suspected UNE site as a function of sampler density and distance from the emission point of gases from a UNE.

Air sampling↗
DOE OSTI2017

New Generation Flask Sampling Technology Final Report

Scientists are turning their focus to the Arctic, site of one of the strongest climate change signals. A new generation of technologies is required to function within that harsh environment, chart evolution of its trace gases and provide new kinds of information for models of the atmosphere. Our response to the solicitation tracks how global atmospheric monitoring was launched more than a half century ago; namely, acquisition of discrete samples of air by flask and subsequent analysis in the laboratory. AOS is proposing to develop a new generation of flask sampling technology. It will enable the new Arctic programs to begin with objective high density sampling of the atmosphere by UAS. The Phase I program will build the prototype flask technology and show that it can acquire and store mol fractions of CH4 and CO2 and value of δ13C with good fidelity. A CAD model will be produced for the entire platform including a package with 100 flasks and the airframe with auto-pilot, electronic propulsion and ground-to-air communications. A mobile flask analysis station will be prototyped in Phase I and designed to final form in Phase II. It expends very small sample per analysis and will interface directly to the flask package integrated permanently into the UAS fuselage. Commercial Applications and Other Benefits: • The New Generation Flask Sampling Technology able to provide a hundred or more samples of air per UAS mission. • A mobile analysis station expending far less sample than the existing ones and small enough to be stationed at the remote sites of Arctic operations. • A new form of validation for continuous trace gas observations from all platforms including the small UAS. • Further demonstration to potential customers of the AOS capabilities to invent, build, deploy and exploit entire platforms for observations of Earth’s atmosphere and ocean. Key Words: Flask Sampler, Mobile Analysis Station, Trace Gas, CO2, CH4, δC13, UAS, Baseline Airborne Observatory, Arctic, Climate Change. Summary for Members of Congress: The air, land and sea of the Arctic combine to produce a large climate change signal. AOS is proposing to develop unmanned airborne technologies able to begin prompt, objective observations of the signal’s atmospheric component.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2012

Whole Module Offgas Test Report: Space-X Dragon Module

Between 7 April and 11 April 2012 a chemist from the JSC Toxicology Group acquired samples of air in 500 ml evacuated canisters from the sealed Dragon Module at the Space-X facility at KSC. Three samples were taken of facility air (two before the test and one after the test), and a total of 9 samples were taken from the sealed module in triplicate at the following times: 0 hours, 48 hours, and 96 hours. The module contained 470 kg, which was 100% of the mass to be launched. Analytical data contained in the Toxicology Group Report (attached) show that the ambient facility air was clean except for almost 9 milligrams per cubic meter of isopropanol (IPA) in the sample taken at the end of the test. Space-X must ensure that IPA is not introduced into the module before it is sealed for launch. Other minor contaminants in the ambient air included the following: perfluoro(2-methyl)pentane and hexamethylcyclotrisiloxane. The first-acquired samples of each triplicate from the module were not analyzed. Analyses of pairs of samples that were taken during the test show excellent agreement between the pairs and a linear increase in the T-values during the 4 days of the test (figure below). The rate of increase averaged 0.124 T units per day. If the time from last purge of the module on the ground to crew first entry on orbit is 10 days, then the T value at first entry should be less than 1.2 units, which is well below the criterion of 3.0 for consideration of additional protection of the crew from offgas products. The primary contributors were as follows: trimethylsilanol (0.057), fluorotrimethylsilane (0.047), acetaldehyde (0.004), hexamethylcyclopentasiloxane (0.003), and toluene (0.002).

James, John T.↗