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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 1,801 records · Page 100
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Raw leaf gas exchange data, Leaf traits and 13CO2 experiment in the Amazon basin, Manaus, Brazil, 2019

This data package contains raw light response curves of mature leaves from 26 individuals, distributed among 18 species with different canopy positions, and leaf traits (LMA, N, P, and NSC) from Manaus-Brazil (June-November 2019). Branches were cut from the tree and re-cut under water. All measurements were made using (Li-6400XT, Li-Cor®, Lincoln, USA) under standard environmental conditions. Also, have data from an experiment with 13CO2 using a combined method with Licor 6400XT and Picarro. The experiment was conducted with one tropical species and measured the concentration of ¹³CO2 and ¹²CO2 to estimate rates of leaf respiration. All the files included in this data package are in .csv format with additional metadata spreadsheets in Excel file formats.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Leaf gas exchange (BNL-PNNL collaboration), San Lorenzo, Panama, 2020

This data package contains Photosynthetic CO2 response (ACi curves) and Light Response (AQ) of mature sunlit canopy leaves of 11 species from PA-SLZ, February 2020. Branches were cut from the top of the canopy and re-cut under water. Fitted Vcmax and Jmax photosynthetic parameters were derived from measured data as well as the convexity, light use efficiency and apparent quantum yield. This data was collected as a collaboration between Brookhaven National Laboratory (BNL) and Pacific Northwest National Laboratory (PNNL), and is a subset of the 2020 BNL Panama campaign. The species included in this dataset are: Apeiba membranacea, Carapa guianensis, Cespedesia spathulate, Jacaranda copaia, Lonchocarpus heptaphyllus, Pera arboea, Pourouma bicolore, Symphonia globulifera, Tachigali versicolor, Tapirira guianensis, and Virola sebifera. The files included in this data package are in .csv and .pdf format, with two Excel files containing additional metadata.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

G-LiHT Campaign Leaf Carbon and Nitrogen Content, Mar2017: Puerto Rico

Measurements of leaf carbon and nitrogen content collected from 68 tropical tree species. Data includes leaves collected from fully sunlit and shaded canopy strata as well as leaves for young, mature, old and senescent leaf ages. Data for each sample includes the relative age estimate, leaf canopy position and sample number. This data was collected as part of the 2017 NGEE-Tropics / NASA G-LiHT airborne campaign. This data package includes processed data for leaf carbon and nitrogen content (*.csv). Metadata files include data description (_dd.csv) for tabular data, site information (*.csv), sampling protocol (*.pdf) and the NGEE-Tropics FRAMES e-field log and file submission metadata (*.xlsx). See related datasets for sample details including photographs, leaf-level reflectance and transmittance spectra, leaf mass per area (LMA) and water content.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Monitoring of dielectric permittivity in accelerated alkali-silica reaction concrete with microwave backscattering

Deterioration of concrete due to the alkali–silica reaction (ASR) involves a reaction between alkaline ions in the cement pore solution and non-crystalline silica found in many aggregates. The product of reaction is a porous hydrophilic ASR gel, which causes expansion and cracking of concrete structure. Currently, there is no reliable method for non-destructive evaluation of ASR. We have investigated the feasibility of using relative dielectric permittivity obtained from X-band microwave backscattering of concrete. Advantages of this method of concrete evaluation are that measurements are non-contact and one-sided, and the approach is scalable to arbitrary-size concrete structures. The exploratory study was performed using an unrestrained set of accelerated ASR concrete prism specimens developed according to the ASTM1293 standard. One set of specimens contained no entrained air, while another set was contained entrained air. The specimens were removed from the environmental chamber at different times during a year-long study to create a set of different ASR maturity specimens. Strain measurements were performed on all specimens. Strain data both air entrained and non-air entrained sets were shown to be in close agreement with Larive model of isothermal unrestrained ASR expansion with similar fitting parameters. Furthermore, relative dielectric permittivity of concrete specimens was correlated with strain data. Both sets show correlation between dielectric permittivity and strain, with stronger linear correlation observed for the air-entrained specimens. Development of such correlation would enable estimating expansion of actual concrete structures from microwave backscattering measurements, which could be used for risk stratification to guide and minimize coring.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Post-Release Survivorship in a New Population of Blanding's Turtles Established Using Headstarted and Directly Released Turtles

Blanding’s Turtles are facing a variety of anthropogenic threats that decrease population viability. We initiated a project to establish a new population of Blanding’s Turtles on a National Wildlife Refuge in Massachusetts using hatchlings obtained from a nearby robust donor population. We released 440 head-started individuals and 401 directly-released hatchlings between 2007–2013 and conducted multiple years of post-release monitoring via aquatic trapping to estimate survival. Between 2014–2021 we released an additional 824 head-started and 433 directly-released individuals and conducted one year of aquatic trapping in 2021 to estimate population size. First year post-release survival of head-started turtles was six times that of directly-released hatchlings (0.72 vs. 0.12, respectively), but annual survival of both groups was 0.78–0.90 in subsequent years. Only 19% of turtles released at <60 mm carapace length (CL) were subsequently recaptured compared to 60% of those released at ≥60 mm CL, supporting 60 mm CL as a target minimum release size. The mean population estimates using two different study designs were 164 and 202, with 91 individuals encountered. Now that turtles released early in the project are approaching reproductive maturity, we recommend resampling and expanding trapping efforts to include more wetlands to assess long-term survival, abundance, and distribution of Blanding’s Turtles in this newly established population. Furthermore, our results, combined with other evaluations of head-starting across the species’ range, add credence to the use of head-starting as a population recovery tool for Blanding’s Turtles.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

AmeriFlux US-Cwt Coweeta

This is the AmeriFlux version of the carbon flux data for the site US-Cwt Coweeta. Site Description - Mature, secondary, deciduous-dominated forest. Located in southern Appalachian mountains, cove location, near base of forested catchment. Proximity close to USFS Coweeta Hydrologic Laboratory offices. Forest harvesting until early 1930s, unmanaged since.

Oishi, A. Christopher↗
DOE OSTI2021

AmeriFlux US-BZS Bonanza Creek Black Spruce

This is the AmeriFlux version of the carbon flux data for the site US-BZS Bonanza Creek Black Spruce. Site Description - Mature black spruce boreal forest with cold, permafrost soils on a peat plateau. In the Tanana lowlands in interior Alaska. Primary wind direction in the summer is WSW.

Euskirchen, Eugenie↗
DOE OSTI2022

AmeriFlux FLUXNET-1F US-Ha1 Harvard Forest EMS Tower (HFR1)

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Ha1 Harvard Forest EMS Tower (HFR1). This is the FLUXNET version of the carbon flux data for the site US-Ha1 Harvard Forest EMS Tower (HFR1) produced by applying the standard ONEFlux (1F) software. Site Description - The Harvard Forest tower is on land owned by Harvard University. The site is designated as an LTER site. Most of the surrounding area was cleared for agrigulture during European settlement in 1600-1700. The site has been regrowing since before 1900 (based on tree ring chronologies) and is now predominantly red oak and red maple, with patches of mature hemlock stand and individual white pine. Overstory trees were uprooted by hurricane in 1938. Climate measurements have been made at Harvard Forest since 1964.

Munger, J. William↗
DOE OSTI2022

AmeriFlux FLUXNET-1F US-BZS Bonanza Creek Black Spruce

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-BZS Bonanza Creek Black Spruce. This is the FLUXNET version of the carbon flux data for the site US-BZS Bonanza Creek Black Spruce produced by applying the standard ONEFlux (1F) software. Site Description - Mature black spruce boreal forest with cold, permafrost soils on a peat plateau. In the Tanana lowlands in interior Alaska. Primary wind direction in the summer is WSW.

Euskirchen, Eugenie↗
DOE OSTI2023

AmeriFlux FLUXNET-1F US-Dix Fort Dix

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Dix Fort Dix. This is the FLUXNET version of the carbon flux data for the site US-Dix Fort Dix produced by applying the standard ONEFlux (1F) software. Site Description - The Fort Dix site is located in the upland forests of the New Jersey Pine Barrens, the largest continuous forested landscape on the Northeastern coastal plain. Upland forests occupy 62% of the 1.1 million acre Pine Barrens and can be divided into three dominant stand types, Oak/Pine (19.1%), Pine/Oak (13.1%), and Pitch Pine/Scrub oak (14.3%). The majority of mature upland forests are the product of regeneration following late 19th century logging and charcoaling activities. Gypsy moths first appeared in the Pine Barrens of New Jersey in 1966. Since the time of arrival, the upland forest stands have undergone several episodes of defoliation, the most significant occurred in 1972, 1981, and 1990. In recent years, the overstory oaks and understory oaks and shrubs of the Fort Dix stand, underwent two periods of defoliation by Gypsy moth, in 2006 and 2007. During these two years, maximum leaf area reached only 70% of the 2005 summer maximum.

Clark, Kenneth↗
DOE OSTI2023

AmeriFlux FLUXNET-1F US-Syv Sylvania Wilderness Area

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Syv Sylvania Wilderness Area. This is the FLUXNET version of the carbon flux data for the site US-Syv Sylvania Wilderness Area produced by applying the standard ONEFlux (1F) software. Site Description - Old growth unmanaged forest consisting primarily of sugar maple and eastern hemlock up to 350 years old,. Note that a small lake to the north. Site was chosen to represent an end member representative of the upland forests in the US_PFa tall tower flux footprint and contrast to nearby mature sites, NEON site US-xUN, US-WCr, and US-UMB. Virtual Site Visit: https://fen.aos.wisc.edu/owncloud/index.php/s/Il31u921iYXbSEO

Desai, Ankur↗
DOE OSTI2024

AmeriFlux AR-Bal Balcarce BA

This is the AmeriFlux version of the carbon flux data for the site AR-Bal Balcarce BA. Site Description - The study was carried out in a 19-ha rainfed soybean plot at the Unidad Integrada Balcarce, located southeast of Buenos Aires, Argentina. The site is located in an environment of gentle hills at 130 m.a.s.l. Its soil was classified as a typical Argiudoll, with a loamy clayey texture up to 0.30 m and between 0.80 to 1.10 m depth, and a clayey texture between 0.30 and 0.80 m depth. The slope was 1:50 and oriented NE to SW. A caliche layer was found at 1 to 1.2 m depth thus the water table was considered beneath that level. The soybean variety used was DM 3810, Maturity Group III with an indeterminate growing habit. It was sown on November 21, 2012, and emerged on December 1. The crop archive had a maximum height of 0.75 m.

Gassmann, Maria Isabel↗
DOE OSTI2025

AmeriFlux FLUXNET-1F US-CRK Davy Crockett National Forest

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-CRK Davy Crockett National Forest. This is the FLUXNET version of the carbon flux data for the site US-CRK Davy Crockett National Forest produced by applying the standard ONEFlux (1F) software. Site Description - Shortleaf pine, mature

Noormets, Asko [Texas A&M University]↗
DOE OSTI2025

AmeriFlux FLUXNET-1F AR-Bal Balcarce BA

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site AR-Bal Balcarce BA. This is the FLUXNET version of the carbon flux data for the site AR-Bal Balcarce BA produced by applying the standard ONEFlux (1F) software. Site Description - The study was carried out in a 19-ha rainfed soybean plot at the Unidad Integrada Balcarce, located southeast of Buenos Aires, Argentina. The site is located in an environment of gentle hills at 130 m.a.s.l. Its soil was classified as a typical Argiudoll, with a loamy clayey texture up to 0.30 m and between 0.80 to 1.10 m depth, and a clayey texture between 0.30 and 0.80 m depth. The slope was 1:50 and oriented NE to SW. A caliche layer was found at 1 to 1.2 m depth thus the water table was considered beneath that level. The soybean variety used was DM 3810, Maturity Group III with an indeterminate growing habit. It was sown on November 21, 2012, and emerged on December 1. The crop archive had a maximum height of 0.75 m.

Gassmann, Maria Isabel [Universidad de Buenos Aire↗
DOE OSTI2026

AmeriFlux US-NC5 NC Butner Farm

This is the AmeriFlux version of the carbon flux data for the site US-NC5 NC Butner Farm. Site Description - The US-NC5 flux tower is located within an 80-year-old mixed pine-hardwood forest at the Umstead Research Farm in Butner, North Carolina. The northern section of this 20-hectare Fall Lake Watershed of the Neuse River Basin in the Piedmont of North Carolina, USA. The Northern portion is currently a managed cattle farm, which is slated for expansion—necessitating forest clearing in the flux site. To establish a reference baseline, a year-long, all-season eddy covariance flux monitoring campaign will be conducted from April 2025 to March 2026. This effort aims to capture the carbon flux dynamics of the mature forest ecosystem prior to a planned land-use conversion. The site will be transitioned into a silvopasture, maintained through prescribed burning and cattle grazing to promote an open-canopy watershed structure. Flux measurements will continue after the conversion.

Sun, Ge [USDA Forest Service]↗
DOE OSTI2026

AmeriFlux FLUXNET-1F BR-Sa1 Santarem-Km67-Primary Forest

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site BR-Sa1 Santarem-Km67-Primary Forest. This is the FLUXNET version of the carbon flux data for the site BR-Sa1 Santarem-Km67-Primary Forest produced by applying the standard ONEFlux (1F) software. Site Description - The LBA Tapajos KM67 Mature Forest site is a closed-canopy terra firme (upland) forest, located in the FLONA Tapajos, or National Forest, a 450,000 ha government conservation unit in the Brazilian Amazon. Bounded by the Tapajos River in the west and highway BR-163 to the east, the tower is located on a flat plateau (or planalto) that extends up to 40 km to the north, south, and east. The forest at the tower site is classified as primary or "old-growth"" predominantly by its uneven age distribution, emergent trees, numerous epiphytes and abundant large logs. In January 2006 and again in November 2023, falling trees hit the tower guy wires destroying the tower and halting measurements. In each case, the tower was restored and measurements resumed, first in August of 2008 (enabled by a Partnership for International Research and Education, or PIRE, grant from the U.S. National Science Foundation) and again in June 2024.

Restrepo-Coupe, Natalia [University of Arizona, Cu↗
DOE OSTI2026

AmeriFlux FLUXNET-1F US-Cwt Coweeta

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-Cwt Coweeta. This is the FLUXNET version of the carbon flux data for the site US-Cwt Coweeta produced by applying the standard ONEFlux (1F) software. Site Description - Mature, secondary, deciduous-dominated forest. Located in southern Appalachian mountains, cove location, near base of forested catchment. Proximity close to USFS Coweeta Hydrologic Laboratory offices. Forest harvesting until early 1930s, unmanaged since.

Oishi, A. Christopher [USDA Forest Service]↗

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