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Results for “Reproducibility of Results”

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 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Validity of a finite temperature expansion for dense nuclear matter

In this work we provide a new, well-controlled expansion of the equation of state of dense matter from zero to finite temperatures (𝑇) while covering a wide range of charge fractions (𝑌 𝑄 ), from pure neutron to isospin symmetric nuclear matter. Our expansion can be used to describe neutron star mergers using the equation of state inferred from neutron star observations. We discuss how knowledge from low-energy nuclear experiments and heavy-ion collisions can be directly incorporated into the expansion. We also suggest new thermodynamic quantities of interest that can be calculated from theoretical models or directly inferred by experimental data that can be used to infer the finite temperature equation of state. With our new method, we can quantify the uncertainty in our finite 𝑇 and 𝑌 𝑄 expansions without making assumptions about the underlying degrees of freedom. We can reproduce results from a microscopic equation of state up to 𝑇 = 100 MeV for baryon chemical potential 𝜇 𝐵 ≳ 1100 MeV [≈(1–2)⁢𝑛 sat ] within 5% error, with even better results for larger 𝜇 𝐵 and/or lower 𝑇. We investigate the sources of numerical and theoretical uncertainty and discuss future directions of study.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2025

MIST_paper

Code to reproduce results from and implement functionality described in "A Bayesian error model for synthesis and sequencing of oligonucleotides", Marrs, FW, Gratz, D, and Erkkila, TH.

Marrs, Frank↗
DOE OSTI2026

STAT_UQ_AI

Code to reproduce results in "Statistical Uncertainty Quantification for Aggregate Performance Metrics in Machine Learning Benchmarks".

Gopalan, Giri↗
DOE OSTI2024

Verified, Archived, Library of Inputs and Data (VALID) Supporting Files

This dataset contains input, output, and sensitivity data files for computational simulations with the SCALE code system as part of the Verified, Archived Library of Inputs and Data (VALID). The simulations cover critical benchmark experiments from the International Criticality Safety Benchmark Evaluation Project. The files are to be housed in a public directory for distribution. The information contained in the files have been approved for release by the Organisation for Economic Co-operation and Development Nuclear Energy Agency (NEA). Users wanting to reproduce results from this dataset are required to obtain a license to the SCALE code system for which details on the distribution can be found here: https://www.ornl.gov/scale/releases.

keff↗
DOE OSTI2026

Data & Code from Phoenix CPPP Phase 2 Analysis

This data and code package supports the analysis presented in “Beyond Surface Cooling: Comprehensive Field Assessment of Reflective Pavement Thermal Performance in Phoenix, Arizona” and provides fully reproducible workflows for evaluating the thermal performance of cool pavement treatments in a hot urban environment. The dataset integrates multi-modal field measurements collected across residential and nonresidential settings, including mobile air temperature traverses, stationary air temperature monitoring, residential mean radiant temperature (MRT) measurements, subsurface temperature profiles, and controlled testbed observations. The data package contains raw and processed datasets in comma-separated value (CSV) format, accompanying metadata files describing site characteristics and measurement protocols, and R scripts (.R files) used for data cleaning, time synchronization, spatial and temporal matching, quality control filtering, statistical comparison, and figure generation. All analyses were conducted using R (version ≥ 4.2.0) with commonly available packages (e.g., tidyverse, lubridate, data.table, ggplot2). No proprietary software is required to reproduce results. Field campaigns were designed to quantify the effects of high-reflectance pavement coatings on surface temperature, near-surface air temperature, subsurface heat propagation, and radiative heat exposure. Temporal alignment procedures include standardized timestamp conversion and nearest-neighbor matching of high-frequency sensor measurements to stop-based metadata within defined tolerance windows to ensure comparability across instruments. The workflows generate summary statistics, treatment–control contrasts, depth-dependent thermal gradients, and time-series visualizations used in the associated publication. By integrating mobile, stationary, radiative, and subsurface measurements within a unified and transparent processing framework, this package enables comprehensive evaluation of cool pavement performance across multiple thermal exposure pathways and supports reuse in future urban heat mitigation and climate resilience studies.

AIR TEMPERATURE↗
NASA NTRS1972

Dynamic measurement of bulk modulus of dielectric materials using a microwave phase shift technique

A microwave Doppler shift technique was developed for measuring the dynamic bulk modulus of dielectric materials such as solid propellants. The system has a demonstrated time resolution on the order of milliseconds and a theoretical spatial resolution of a few microns. Accuracy of the technique is dependent on an accurate knowledge of the wavelength of the microwave in the sample being tested. Such measurement techniques are discussed. Preliminary tests with two solid propellants, one non-aluminized and one containing 16% aluminum, yielded reasonable, reproducible results. It was concluded that with refinements the technique holds promise as a practical means for obtaining accurate dynamic bulk modulus data over a variety of transient conditions.

Barker, B. J.↗
NASA NTRS1976

Method and apparatus for tensile testing of metal foil

A method for obtaining accurate and reproducible results in the tensile testing of metal foils in tensile testing machines is described. Before the test specimen are placed in the machine, foil side edges are worked until they are parallel and flaw free. The specimen are also aligned between and secured to grip end members. An aligning apparatus employed in the method is comprised of an alignment box with a longitudinal bottom wall and two upright side walls, first and second removable grip end members at each end of the box, and a means for securing the grip end members within the box.

Wade, O. W.↗
NASA NTRS1976

A study of the toxicology of pyrolysis gases from synthetic polymers

An apparatus and procedure for evaluating the toxicity of pyrolysis gases from synthetic polymers are described. In each test, four Swiss albino mice are exposed in a 5-liter chamber to the gases from materials pyrolyzed at 700 C. The apparatus is simple in design, easy to clean, inexpensive and gives reproducible results. Data on several fluorine-containing and polyamide polymers are presented.

Young, W.↗
NASA NTRS1976

Electrical conductivity measurements on silicate melts using the loop technique

A new method is described for measurement of the electrical conductivity of silicate melts under controlled oxygen partial pressure at temperatures to 1550 C. The melt samples are suspended as droplets on platinum-rhodium loops, minimizing iron loss from the melt due to alloying with platinum, and providing maximum surface exposure of the melt to the oxygen-buffering gas atmosphere. The latter provides extremely rapid equilibration of the melt with the imposed oxygen partial pressure. The loop technique involves a minimum of setup time and cost, provides reproducible results to within + or - 5% and is well suited to electrical conductivity studies on silicate melts containing redox cations.

Waff, H. S.↗
NASA NTRS1978

Post-shock temperatures in minerals

Post-shock temperatures were measured in a wide variety of materials, including those of geophysical interest such as silicates by using an infrared detector to determine the brightness temperature of samples shocked to pressures in the range 5 to approximately 30 GPa. Measurements were made in the 4.5 to 5.75 micron and in the 7 to 14 micron wavelength ranges. Reproducible results, withe the temperatures in the two wavelength bands generally in excellent agreement, were obtained for aluminum-2024 (10.5 to 33 GPa; 125 to 260 C), stainless steel-304 (11.5 to 50 GPa; 80 to 350 C), crystalline quartz (5.0 to 21.5 GPa; 80 to 250 C) forsterite (7.5 to 28.0 GPa; approximately 30 to 160 C) and Bamble bronzite (6.0 to 26.0 GPa; approximately 30 to 225 C). Results are generally much higher at low pressures than the values calculated assuming a hydrodynamic rheology and isentropic release parallel to the Hugoniot but tend towards them at higher pressures.

Raikes, S. A.↗
NASA NTRS1978

Fire toxicology program. JSC methodology

Toxicological testing of spacecraft materials was initiated in 1965. Toxicological evaluations of the pyrolysis/combustion products of candidate spacecraft materials were performed using a modified 142 liter Bethlehem Chamber equipped with a Linberg Model 55031 furnace external to the chamber. In all of the assessments, lethality was chosen as the endpoint. A new pyrolysis/combustion chamber was developed for toxicological testing and ranking of both spacecraft and aircraft materials. The pyrolysis/combustion chamber permits the use of both behavior and physiological measurements as indicators of incapacitation. Methods were developed which employ high resolution gas chromatography/mass spectrometry to generate chamber atmospheric profiles which indicate the reproductibility of pyrolysate concentrations. The atmospheric volatile profiles in combination with CO, CO2, and O2 analysis indicates that small chamber equipped with an internal furnace will give reproducible results.

Schneider, H.↗
NASA NTRS1979

Post-shock temperatures in minerals

An experimental technique was developed for measuring post-shock temperatures in a wide variety of materials, including those of geophysical interest such as silicates. The technique uses an infrared radiation detector to determine the brightness temperature of samples shocked to pressures in the range 5 to approximately 30 GPa; in these experiments measurements were made in two wavelength ranges (4.5 to 5.75 microns and 7 to 14 microns). Reproducible results, with the temperatures in the two wavelength bands generally in excellent agreement, were obtained for aluminum-2024 (10.5 to 33 GPa, 125 to 260 C), stainless steel-304 (11.5 to 50 GPa, 80 to 350 C), crystalline quartz (5.0 to 21.5 GPa, 80 to 250 C), forsterite (7.5 to 28.0 GPa, approximately 30 to 160 C) and Bamble bronzite (6.0 to 26.0 GPa, approximately 30 to 225 C). It is concluded that release adiabat data should be used, wherever available, for calculations of residual temperature, and that adequate descriptions of the shock and release processes in minerals are more complex than generally assumed.

Raikes, S. A.↗
NASA NTRS1982

A study comparing several isocyanate and isothiocyanate derivatives of Porasil C for the separation of lower hydrocarbons by GC

Several isocyanate and isothiocyanate derivatives of Porasil C were synthesized and evaluated for the separation of the low-molecular-weight saturated and unsaturated hydrocarbons. It was shown that different functional groups significantly affect the retention behavior of the more polar unsaturated hydrocarbons, and that reproducible results can be obtained if dry carrier gas is used.

Pollock, G. E.↗
NASA NTRS1982

Electron microprobe analysis of trace elements in minerals at 10 PPM concentrations

An improved technique is developed for measuring backgrounds during trace element analysis of crystals and glass using electron microprobes. This technique overcomes major difficulties encountered with conventional techniques, such as the problem of obtaining the net X-ray intensity of the characteristic emission line of interest with sufficient precision and accuracy, as well as the error due to the inability to directly measure the intensity at the wavelength of the characteristic line on the sample being analyzed. It is shown that this technique can yield reproducible results to within 4 ppm in olivine, and has a minimum uncertainty and detection limit of 10 ppm Nd in olivine.

Mckay, G. A.↗
NASA NTRS1982

Vomiting Center reanalyzed: An electrical stimulation study

Electrical stimulation of the brainstem of 15 decerebrate cats produced stimulus-bound vomiting in only 4 animals. Vomiting was reproducible in only one cat. Effective stimulating sites were located in the solitary tract and reticular formation. Restricted localization of a vomiting center, stimulation of which evoked readily reproducible results, could not be obtained.

Miller, A. D.↗
NASA NTRS1982

Experimental study of electrochemical fluorination of trichloroethylene

The electrochemical fluorination of trichloroethylene in anhydrous hydrogen fluoride at 0 C and at constant cell potential was investigated. A microprocessor-aided electrochemical fluorination reactor system that yields highly reproducible results was utilized. The following major two-carbon-chain products were observed: CHCl2-CCl2F, CHCl2-CClF2, CHClF-CCl2F, and CCl2F-CClF2. The first step in the reaction sequence was determined to be fluorine addition to the double bond, followed by replacement of first hydrogen and then chlorine by fluorine. Polymerization reactions yielded higher molecular weight or possible ring-type chlorofluorohydrocarbons. A comparison of the reaction products of electrochemical and chemical fluorinations of trichloroethylene is also discussed.

Polisena, C.↗
NASA NTRS1983

An assessment of flow-field simulation and measurement

The effectiveness of the instrumentation, techniques, and wind tunnel flow characterizations in the U.S. large scale wind tunnels for accuracy in making increasingly finer drag measurements on airfoils is assessed. The more reliable measurement is necessary due to refined designs of airfoils and the need to continue to improve the economic performance of commercial aircraft. Consequently, the effects of flows in wind tunnels, compared with those in the freestream environment, have become a critical factor. Dynamic flow properties in individual wind tunnels have to be documented in order to assure reproducible results. Laser velocimetry is a suitable tool for nonintrusive measurement of the mean velocity, turbulence intensity, and the shear stress in wind tunnel flowfields. It is suggested that future wind tunnel studies be designed to remain within the diagnostic capabilities available at the site.

Owen, F. K.↗