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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 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

A method to measure the atmospheric aerosol content using ERTS-1 data

The apparent gradual increase of particles in the atmosphere has received considerable attention in recent years due to the possible effect of atmospheric aerosols on the earth's climate. The ERTS-1 satellite offered the opportunity of determining the feasibility of monitoring the atmospheric aerosol content on a global basis, as suggested by theoretical studies, which showed a linear relationship between the upwelling earth atmosphere radiance and the aerosol content. This relationship was investigated at two test sites, San Diego and the Salton Sea, using the MSS radiance data, with ground truth observations of the aerosol content being made with a Volz photometer at the time of the satellite overpasses. Significant results, relating the radiance over water surfaces to the atmospheric aerosol content, have been obtained. The results indicate that the MSS channels, 4, 5 and 6 centered at 0.55, 0.65 and 0.75 micron have comparable sensitivity, and that the aerosol content can be determined within + or - 10% with the assumed measurement errors of the MSS.

Griggs, M.↗
NASA NTRS1983

Transmittance and reflectance of crystalline quartz and highand low-water content fused silica from 2 microns to 1 mm

The transmittances and reflectances of cultured crystalline quartz, Suprasil, Suprasil W, and Infrasil were compared over the wavelength region from 2 to 1000 microns. The high-water content of Suprasil and the low-water content of cultured crystalline quartz, Suprasil W, and Infrasil were determined by their transmittances measured at 2.73 microns where water content causes high absorption in optical materials. The fact that the fused silicas, both with high- and low-water content, had identical far-IR transmittances and that their transmittances were greatly inferior to that of crystalline quartz led to the conclusion that their inferior transmittance is due to their amorphous structure and not to their water content.

Heaney, J. B.↗
NASA NTRS1993

Norepinephrine content in discrete brain areas and neurohypophysial vasopressin in rats after a 9-d spaceflight (SLS-1)

The norepinephrine (NE) content in discrete brain areas and the vasopressin content in the neurohypophysial system were assessed in rats after a 9-d spaceflight and after a recovery period. The NE content in the locus coeruleus decreased significantly in spaceflight rats, but showed no difference between control and flight animals after a 9-d recovery. These findings were probably due to an acute stress undergone during landing. The NE content was unchanged in the A2 and A5 cell groups. In rats flown aboard SLS-1, the vasopressin content was increased in the posterior pituitary, and was significantly decreased in the hypothalamus. We conclude that the NE depletion in the locus coeruleus and the alteration in vasopressin release were consistent with an acute stress, likely occurring during and/or after landing. These changes tend to mask the actual neuroendocrine modifications caused by microgravity.

Fareh, Jeannette↗
NASA NTRS1997

Ultrasound Algorithm Derivation for Soil Moisture Content Estimation

Soil moisture content can be estimated by evaluating the velocity at which sound waves travel through a known volume of solid material. This research involved the development of three soil algorithms relating the moisture content to the velocity at which sound waves moved through dry and moist media. Pressure and shear wave propagation equations were used in conjunction with soil property descriptions to derive algorithms appropriate for describing the effects of moisture content variation on the velocity of sound waves in soils with and without complete soil pore water volumes, An elementary algorithm was used to estimate soil moisture contents ranging from 0.08 g/g to 0.5 g/g from sound wave velocities ranging from 526 m/s to 664 m/s. Secondary algorithms were also used to estimate soil moisture content from sound wave velocities through soils with pores that were filled predominantly with air or water.

Belisle, W.R.↗
NASA NTRS1987

Oxidative processes in soybean and pea seeds: effect of light, temperature, and water content

Oxidative processes are probable determinants of longevity of seeds in storage. Measurements of actual oxygen uptake rates were made for soybean and pea seeds as a comparison of short and long lived seeds when light, temperature, and moisture contents were varied. In both peas and soybeans, the oxygen uptake was depressed at low temperatures (<16 degrees C) and low water contents (< 0.25 gram H2O per gram dry weight). Apparent activation energies under these conditions are very high, while apparent activation energies of seeds at higher water contents and at temperatures greater than 22 degrees C are much less. Light enhances the level of oxygen uptake in pea, but reduces the level of oxygen uptake in soybean. The complexities of the interactions of oxygen uptake with environmental conditions in soybean compared to pea suggest that oxidative processes occur in soybean at low water contents, but are essentially absent in pea. It is suggested that the additional oxidative processes in soybean with moisture contents between 0.10 and 0.24 gram per gram may contribute to the poorer longevity of soybean seed compared to pea seed.

NASA Program Space Biology↗
NASA NTRS1996

Effect of CO2 levels on nutrient content of lettuce and radish

Atmospheric carbon-dioxide enrichment is known to affect the yield of lettuce and radish grown in controlled environments, but little is known about CO2 enrichment effects on the chemical composition of lettuce and radish. These crops are useful model systems for a Controlled Ecological Life-Support System (CELSS), largely because of their relatively short production cycles. Lettuce (Lactuca sativa L.) cultivar 'Waldmann's Green' and radish (Raphanus sativus L.) cultivar 'Giant White Globe' were grown both in the field and in controlled environments, where hydroponic nutrient solution, light, and temperature were regulated, and where CO2 levels were controlled at 400, 1000, 5000, or 10,000 ppm. Plants were harvested at maturity, dried, and analyzed for proximate composition (protein, fat, ash, and carbohydrate), total nitrogen (N), nitrate N, free sugars, starch, total dietary fiber, and minerals. Total N, protein N, nonprotein N (NPN), and nitrate N generally increased for radish roots and lettuce leaves when grown under growth chamber conditions compared to field conditions. The nitrate-N level of lettuce leaves, as a percentage of total NPN, decreased with increasing levels of CO2 enrichment. The ash content of radish roots and of radish and lettuce leaves decreased with increasing levels of CO2 enrichment. The levels of certain minerals differed between field- and chamber-grown materials, including changes in the calcium (Ca) and phosphorus (P) contents of radish and lettuce leaves, resulting in reduced Ca/P ratio for chamber-grown materials. The free-sugar contents were similar between the field and chamber-grown lettuce leaves, but total dietary fiber content was much higher in the field-grown plant material. The starch content of growth-chamber lettuce increased with CO2 level.

NASA Discipline Life Support Systems↗
NASA NTRS2000

Correlation of lycopene measured by HPLC with the L, a, b color readings of a hydroponic tomato and the relationship of maturity with color and lycopene content

Tomatoes (Lycopersicon esculentum cv. Laura) were separated, according to the ripening stage, by a sensory panel into seven groups, and color was measured on the tomato surface with a Minolta Chroma meter. The L, a, b, hue, chroma, and lycopene content were plotted against the maturity stages of the tomatoes, and several good correlations were found. The a/b ratio and the lycopene content were the parameters that allowed six of seven maturity groups in the tomato to be statistically distinguished. The lycopene content, measured by HPLC, was also correlated with the color measurements, and the a, a/b, and (a/b)(2) color factors produced the best regressions. An estimation of the lycopene content in tomatoes can be achieved by using a portable chroma meter, with a possible field usage application. Equations to calculate the lycopene content of tomatoes based on the color readings are reported.

Non-NASA Center↗
NASA NTRS2010

Results and Conclusions from the NASA Isokinetic Total Water Content Probe 2009 IRT Test

The NASA Glenn Research Center has developed and tested a Total Water Content Isokinetic Sampling Probe. Since, by its nature, it is not sensitive to cloud water particle phase nor size, it is particularly attractive to support super-cooled large droplet and high ice water content aircraft icing studies. The instrument comprises the Sampling Probe, Sample Flow Control, and Water Vapor Measurement subsystems. Results and conclusions are presented from probe tests in the NASA Glenn Icing Research Tunnel (IRT) during January and February 2009. The use of reference probe heat and the control of air pressure in the water vapor measurement subsystem are discussed. Several run-time error sources were found to produce identifiable signatures that are presented and discussed. Some of the differences between measured Isokinetic Total Water Content Probe and IRT calibration seems to be caused by tunnel humidification and moisture/ice crystal blow around. Droplet size, airspeed, and liquid water content effects also appear to be present in the IRT calibration. Based upon test results, the authors provide recommendations for future Isokinetic Total Water Content Probe development.

Reehorst, Andrew↗
NASA NTRS2015

Mantle Water Contents Beneath the Rio Grande Rift (NM, USA): FTIR Analysis of Rio Puerco and Kilbourne Hole Peridotite Xenoliths

Peridotite xenoliths from the Rio Grande Rift (RGR) are being analyzed for H (sub 2) O contents by FTIR (Fourier Transform Infrared) as well as for major and trace element compositions. Nine samples are from the Rio Puerco Volcanic Field (RP) which overlaps the central RGR and southeastern Colorado Plateau; seventeen samples are from Kilbourne Hole (KH) in the southern RGR. Spinel Cr# (Cr/(Cr+Al)) (0.08-0.46) and olivine Mg# (Mg/(Mg plus Fe)) (0.883-0.911) of all RGR samples fall within the olivine-spinel mantle array from [1], an indicator that peridotites are residues of partial melting. Pyroxene H (sub 2) O in KH correlate with bulk rock and pyroxene Al (sub 2) O (sub 3).The KH clinopyroxene rare earth element (REE) variations fit models of 0-13 percent fractional melting of a primitive upper mantle. Most KH peridotites have bulk-rock light REE depleted patterns, but five are enriched in light REEs consistent with metasomatism. Variation in H (sub 2) O content is unrelated to REE enrichment. Metasomatism is seen in RP pyroxenite xenoliths [2] and will be examined in the peridotites studied here. Olivine H (sub 2) O contents are low (less than or equal to 15 parts per million), and decrease from core to rim within grains. This is likely due to H loss during xenolith transport by the host magma [3]. Diffusion models of H suggest that mantle H (sub 2) O contents are still preserved in cores of KH olivine, but not RP olivine. The average H (sub 2) O content of Colorado Plateau clinopyroxene (670 parts per million) [4] is approximately 300 parts per million higher than RGR clinopyroxene (350 parts per million). This upholds the hypothesis that hydration-induced lithospheric melting occurred during flat-slab subduction of the Farallon plate [5]. Numerical models indicate hydration via slab fluids is possible beneath the plateau, approximately 600 kilometers from the paleo-trench, but less likely approximately 850 kilometers away beneath the rift [6].

Schaffer, L. A.↗
NASA NTRS2017

Towards a Preservation Content Standard for Earth Observation Data

Information from Earth observing missions (remote sensing with airborne and spaceborne instruments, and in situ measurements such as those from field campaigns) is proliferating in the world. Many agencies across the globe are generating important datasets by collecting measurements from instruments on board aircraft and spacecraft, globally and constantly. The data resulting from such measurements are a valuable resource that needs to be preserved for the benefit of future generations. These observations are the primary record of the Earths environment and therefore are the key to understanding how conditions in the future will compare to conditions today. Earth science observational data, derived products and models are used to answer key questions of global significance. In the near-term, as long as the missions data are being used actively for scientific research, it continues to be important to provide easy access to the data and services commensurate with current information technology. For the longer term, when the focus of the research community shifts toward new missions and observations, it is essential to preserve the previous mission data and associated information. This will enable a new user in the future to understand how the data were used for deriving information, knowledge and policy recommendations and to repeat the experiment to ascertain the validity and possible limitations of conclusions reached in the past and to provide confidence in long term trends that depended on data from multiple missions. Organizations that collect, process, and utilize Earth observation data today have a responsibility to ensure that the data and associated content continue to be preserved by them or are gathered and handed off to other organizations for preservation for the benefit of future generations. In order to ensure preservation of complete content necessary for understanding and reusing the data and derived digital products from todays missions, it is necessary to develop a specification of such preservation content. While there are existing standards that address archival and preservation in general, there are no existing international standards or specifications today to address what content should be preserved. The purpose of this paper is to outline briefly the existing standards that apply to preservation, describe a recent effort in getting an international standard in place for specifying preservation content for Earth observation data and derived digital data products and the remaining work needed to arrive at a standard.

ISO Standards↗
NASA NTRS2018

Developing a Standard for Earth Observation Data Preservation Content - A Path to Future Usability

For datasets to be usable, many pieces of information in addition to the data themselves are essential. During the active parts of the lifecycle of dataset generating projects, the needed information is usually accessible through individuals familiar with the various aspects of the projects. However, the utility of datasets tends to outlive the lives of projects, by several decades in many cases. Thus it is essential to capture all the relevant information about the datasets, data, metadata and associate knowledge that is sufficient to read, understand, interpret and reuse the datasets, while the projects are still active. The capture and preservation should be such that the data are usable when no consultation is available from the original project participants. Identification of specific categories of content through an international standard is beneficial to the user communities of the future, so that projects involving Earth observations and generating data products can consistently plan for preservation and future usability of the project outcomes. While there are existing standards that address archival and preservation in general, there are no existing international standards or specifications today to address what content should be preserved. The standard, ISO 19165-1, titled "Geographic Information - Preservation of digital data and metadata Part 1: Fundamentals" considers geographic information preservation in general. It acknowledges that "specific content items needed to preserve the full provenance and context of the data and associated metadata depend on the needs of the designated community and types of datasets (e.g., maps, remotely sensed data from satellites and airborne instruments, physical samples). Follow-up parts to this standard may be developed detailing content items appropriate to individual disciplines." NASA proposed an extension to this standard, titled "Geographic information -- Preservation of digital data and metadata -- Part 2: Content specifications for Earth observation data and derived digital products." The development of this extension is in progress with participation by an international team representing nine countries. The purpose of this paper is to introduce this standard and report on its status.

Remote Sensing; Data Systems; Open Data;↗
DOE OSTI2013

Expanded Content Envelope For The Model 9977 Packaging

An Addendum was written to the Model 9977 Safety Analysis Report for Packaging adding a new content consisting of DOE-STD-3013 stabilized plutonium dioxide materials to the authorized Model 9977 contents. The new Plutonium Oxide Content (PuO{sub 2}) Envelope will support the Department of Energy shipment of materials between Los Alamos National Laboratory and Savannah River Site facilities. The new content extended the current content envelope boundaries for radioactive material mass and for decay heat load and required a revision to the 9977 Certificate of Compliance prior to shipment. The Addendum documented how the new contents/configurations do not compromise the safety basis presented in the 9977 SARP Revision 2. The changes from the certified package baseline and the changes to the package required to safely transport this material is discussed.

42 ENGINEERING↗
DOE OSTI2018

Neutron Gamma-Method for Monitoring Ash Content of Coal

A brief analysis is given of the modern instrumental methods of monitoring the ash content of coal. Their particulars and drawbacks are examined. A neutron gamma-method of monitoring the ash content is proposed on the basis of integrated use of prompt γ-radiation accompanying inelastic scattering of fast neutrons and radiative capture of thermal neutrons by nuclei of the primary elements comprising the organic and mineral components of coal. The instrumental-methodological parameters of monitoring (sizes of the analyzed samples, energy intervals of the detected gamma radiation) making it possible to the increase the sensitivity of the method with respect to the ash content and to minimize the impact of the variability of the moisture content of coal on its material composition, are optimized. The method has been certified and recommended for representative monitoring of the quality of coarse coal.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2016

An experimental investigation on acoustic emission characteristics of sandstone rockburst with different moisture contents

Rockburst occurred frequently during deep mining in China. The mechanism of rockburst is very complicated and related to many factors. In order to investigate the influence of moisture contents of rockmass on rockburst, we conducted a series of laboratory rockburst experiments of sandstone under three different moisture contents by the Modified True-Triaxial Apparatus (MTTA), in which the acoustic emission (AE) system was employed to monitor the internal damage of rock mass. A high-speed video camera was utilized to record the detail of rockburst. Based on the experimental results, the AE characteristics, such as AE count, AE energy, and AE frequency, were analyzed. The rockburst process, type, and indensity under different moisture contents were discussed. The research results show that with the increase of moisture contents, rock strength was soften, the elastic and the cumulative damage of the rock were reduced, resulting in a gradual decrease in AE cumulative counts and cumulative energy over the course of rockburst. Finally, this study provides an experimental basis and reference for better understanding to the rockburst mechanism and control.

58 GEOSCIENCES↗
DOE OSTI2018

Inclusion Characterization in Aluminum-Deoxidized Special Steel with Certain Sulfur Content Under Combined Influences of Slag Refining, Calcium Treatment, and Reoxidation

Inclusions in Al-killed steel with [S] of about 0.0060 to 0.0070 mass pct were characterized and discussed, evaluating the combined effects of basic slag refining and Ca treatment in ladle, together with reoxidation of liquid steel in casting tundish. Inclusions were changed from Al{sub 2}O{sub 3} to MgO-Al{sub 2}O{sub 3} spinel and then to MgO-Al{sub 2}O{sub 3}-CaO during basic slag refining. After Ca treatment, many (MgO-Al{sub 2}O{sub 3}) + CaS inclusions were formed, featuring the coexistence of MgO-Al{sub 2}O{sub 3} and CaS to form a dual-phased structure. In the following Ar blowing, the number density of (MgO-Al{sub 2}O{sub 3}) + CaS inclusions and pure CaS increased obviously, which implied that [Ca] preferentially reacted with [S] rather than [O] in steel. Reoxidation in casting tundish caused the pickup of oxygen in steel, and the rise of total oxygen (T.O) was 0.0002 mass pct; even 55t steel has been poured. As a result, the content of CaO in inclusions increased and MgO-Al{sub 2}O{sub 3}-CaO inclusions were formed again. Thermodynamic calculations revealed that the driving force was strong for the formation of CaS-based inclusions. Higher carbon content in steel would help to reduce oxygen content while enhancing the activity of [S] in steel, which further stabilized the existence of CaS-based inclusions. Therefore, inclusions were mostly the solid (MgO-Al{sub 2}O{sub 3}) + CaS dual-phase ones, without the formation of liquid calcium aluminates. Contents of CaS and CaO in inclusions were affected by the [mass pct S]/[mass pct O] ratio, which was calculated as about 4.58 K and 5.34 K at 1873 K and 1823 K, respectively. This finding implied that lower oxygen was not favorable to prevent the solid inclusions in the calcium treatment of high carbon special steel.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Nonlinear response of hail precipitation rate to environmental moisture content: A real case modeling study of an episodic midlatitude severe convective event: Hail and Environmental Moisture

The dependence of hail production on initial moisture content in a simulated midlatitude episodic convective event occurred in northeast China on 10–11 June 2005 was investigated using the Weather Research and Forecasting (WRF) model with a double-moment microphysics scheme where both graupel and hail are considered. Three sensitivity experiments were performed by modifying the initial water vapor mixing ratio profile to 90% (“Q-10%”), 105% (“Q+5%”), and 110% (“Q+10%”) of the initial conditions used for the control simulation. It was found that increasing the initial water vapor content caused the hail and total precipitation rates to increase during the first 5 h. The precipitation response to increasing water vapor content was monotonic for this first episode; however, for the event's second episode, the hail precipitation rate responds to the initial water vapor profile nonlinearly, while the total precipitation rate responds mostly monotonically. In particular, simulation Q+5% achieves the largest hail production rate while simulation Q+10% has the largest total precipitation rate. In contrast, during the second episode simulation Q-10% has the strongest vertical motion, produces the most cloud ice and snow, but has the lowest hail production. Analysis shows that increasing the initial moisture content directly increases the precipitation during the first episode, which subsequently induces a stronger, longer-asting cold pool that limits the development of deep convection during the second episode.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Optimization of the autoclave preparation process for improving resistant starch content in rice grains

Abstract The autoclave preparation process to increase the content of resistant starch (RS) in rice grains was optimized, and the results showed that the optimal preparation process was obtained with a water content of 41.63%, a pH of 5.95, an autoclave time of 60.96 min, and a refrigeration time of 17.11 hr. Under these conditions, the theoretical value of RS content in rice grains reached 17.57%. After autoclaving, the estimated glycemic index (EGI) in rice grains was reduced from 78.35 to 66.08 measured after cooking, suggesting that autoclaving was capable of increasing the RS content in rice grains and reducing its EGI value. These results may help spark new concepts and methods for the development of specialized foods for specific populations, such as people with diabetes.

Zheng, Yunzhan↗
DOE OSTI2021

A TTL-based Approach for Content Placement in Edge Networks

Edge networks are promising to provide better services to users by provisioning computing and storage resources at the edge of networks. However, due to the uncertainty and diversity of user interests, content popularity, distributed network structure, cache sizes, it is challenging to decide where to place the content, and how long it should be cached. In this paper, we study the utility optimization of content placement at edge networks through timer-based (TTL) policies. We propose provably optimal distributed algorithms that operate at each network cache to maximize the overall network utility. Our TTL-based optimization model provides theoretical answers to how long each content must be cached, and where it should be placed in the edge network. Extensive evaluations show that our algorithm significantly outperforms path replication with conventional caching algorithms over some network topologies.

Panigrahy, Nitish K.↗