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Goddard, W. A., III

Publications and source records attributed to Goddard, W. A., III.

6 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2011

First Principles Based Reactive Atomistic Simulations to Understand the Effects of Molecular Hypervelocity Impact on Cassini's Ion and Neutral Mass Spectrometer

We report here on the predicted impact of species such as ice-water, CO2, CH4, and NH3, on oxidized titanium, as well as HC species on diamond surfaces. These simulations provide the dynamics of product distributions during and after a hypervelocity impact event, ionization fractions, and dissociation probabilities for the various species of interest as a function of impact velocity (energy). We are using these results to determine the relevance of the fragmentation process to Cassini INMS results, and to quantify its effects on the observed spectra.

hypervelocity collisions↗
NASA NTRS2006

Expanding the Capabilities of the JPL Electronic Nose for an International Space Station Technology Demonstration

An array-based sensing system based on polymer/carbon composite conductometric sensors is under development at JPL for use as an environmental monitor in the International Space Station. Sulfur dioxide has been added to the analyte set for this phase of development. Using molecular modeling techniques, the interaction energy between SO2 and polymer functional groups has been calculated, and polymers selected as potential SO2 sensors. Experiment has validated the model and two selected polymers have been shown to be promising materials for SO2 detection.

electronic noses↗
NASA NTRS2006

Use of the JPL Electronic Nose to detect leaks and spills in an enclosed environment

An electronic nose to be used as an air quality monitor in human habitats in space has been developed at the Jet Propulsion Laboratory. This device is capable of detecting, identifying and quantifying several organic and inorganic chemical species which might be present as contaminants in spacecraft air. The complete portable device, including sensors, electronics, and software for data analysis, has been extensively tested.

environmental monitoring↗
NASA NTRS1975

Theoretical description of the 2A/double prime/ and 2A/prime/ states of the peroxyformyl radical

Simple orbital ideas are used to describe the lowest two states of the peroxyformyl radical, and ab initio Hartree-Fock calculations in these states are reported. It is found that both states may be formed exothermically by association of O2 and HCO in their ground states; however, the excited state may decompose readily to OH and CO2. The possible role of such processes in oxidation of aldelydes is discussed.

Winter, N. W.↗
NASA NTRS1971

Group theoretical selection rules for electron-impact spectroscopy.

Simple group theoretical principles are applied to the consideration of electron scattering off atoms and diatomic and polyatomic molecules. This approach is also used to estimate relative strengths of electron-impact-induced transitions of diatomic and polyatomic molecules.

Goddard, W. A., III↗