The absolute cross section for photoionization of atomic oxygen from the 2p4 3P ground state of O(0)
NASA Technical Reports Server (NTRS)
An experiment to determine the absolute value of the photo-ionization cross section of atomic oxygen
An experiment to determine the absolute value of the photo-ionization cross section of atomic oxygen is described. The atoms are produced in an electrical discharge in oxygen gas with 1% hydrogen added. In order to prevent recombination a crossed beam tec...
National Technical Information Service (NTIS)
The absolute rate constant for the reaction of ground state oxygen atoms with methyl radicals is reported. The methyl radicals were generated by the reaction of oxygen atoms with ethylene in a fast flow reactor, and were detected by a photoionization mass...
The major constituent in the atmosphere of the Earth at altitudes between 200 and 500km is atomic oxygen. Collisions involving atomic oxygen are therefore important in this region of the atmosphere. Due to the difficulty in producing atomic oxygen in the laboratory, there ...
Energy Citations Database
There is a problem with the absolute abundance measurements of oxygen. One of these calibrated measurements is in error, either oxygen in air, or oxygen in (V-SMOW), Vienna's standard mean ocean water reference material. Nier's measurement in air is proba...
Absolute atomic oxygen ground state densities in a radio-frequency driven atmospheric pressure plasma jet, operated in a helium-oxygen mixture, are determined using diagnostic based modeling. One-dimensional numerical simulations of the electron dynamics are combined with time integrated optical emission ...
NASA Astrophysics Data System (ADS)
The atom-beam recoil technique was used to measure absolute total cross sections for the scattering of electrons by atomic and molecular oxygen at 22 energies between 0.5 and 11.3 eV, with additional data obtained up to 100 eV. In this method, a modulated...
The atom beam recoil technique was used to measure absolute total cross sections for the scattering of electrons by atomic and molecular oxygen at 22 energies between 0.5 and 11.3 eV, with additional data obtained up to 100 eV. In this method, a modulated...
Aug 24, 2011 ... A horizon-scanning photometer experiment measured the absolute brightness of the yellow sodium D lines and the atomic oxygen green line ...
NASA Website
The absolute values of photoionization cross sections of atomic oxygen were measured from the ionization threshold to 120 A. An auto-ionizing resonance belonging to the 2S2P4(4P)3P(3Do, 3So) transition was observed at 479.43 A and another line at 389.97 A...
The relative and absolute intensities of trimethylaluminum (TMA), iron pentacarbonyl, lead tetraethyl, and nitrogen oxide upon reaction with atomic oxygen were studied experimentally. The results have shown that the TMA and oxygen reaction created the str...
A novel calibration method for the determination of absolute species densities by laser spectroscopy with two-photon absorption is presented. The method is based on a comparative measurement with a noble gas which has a two-photon resonance spectrally close to the transition investigated. Application of this scheme for the calibration of LIF measurements to determine ...
The compact measurement system for absolute density of oxygen (O) atom has been developed, which employs a vacuum ultraviolet absorption spectroscopy (VUVAS) technique with a high-pressure microdischarge hollow cathode lamp (MHCL) as a light source. The influences of self-absorption, emission line profile of the MHCL, and background ...
Absolute total cross sections for the Ne + Ne, Ar + Ar and O2 + O2 interactions have been measured in the thermal energy range using the crossed nozzle beam technique. The atom-atom total cross section measurements are regarded as sufficiently accurate to...
Results of work carried out mostly in flow systems to escribe the kinetic behavior of F atoms, FO, and NF free radicals are summarized. Some topics surveyed are production of ground state halogen atoms and measurement of atom concentrations as absolute concentrations and by atomic resonance, ...
Absolute cross sections for the excitation of the OI 3s (triplet S(0)) and 3s (quintet S(0)) states by electron impact on atomic oxygen have been measured for electron energies from threshold to 300 eV. Both cross sections are larger than the values predi...
... Title : REACTION OF OXYGEN ATOMS WITH TETRAFLUOROETHYLENE IN THE PRESENCE OF MOLECULAR OXYGEN. ...
DTIC Science & Technology
... Title : Excitation of Oxygen Atoms by Electrons,. ... Descriptors : *OXYGEN, ELECTRONS, ELECTRON TRANSITIONS, ELECTRON IRRADIATION. ...
... AND OXYGEN ATOMS IN A RAREFIED FLAME OF CARBON MONOXIDE AND OXYGEN MIXTURE IN PRESENCE OF SMALL ADMIXTURES OF ...
... Title : DETERMINATION AND APPLICATION OF ABSOLUTE TRANSITION PROBABILITIES AND LIFETIMES OF ATOMS, MOLECULES, AND IONS ...
... Title : ABSOLUTE CHEMILUMINESCENT REACTION RATES FOR EMISSION OF THE O2 HERZBERG BANDS IN OXYGEN AND OXYGEN-INERT ...
Oligonucleotides, in which one of the two nonbridging oxygen atoms of internucleotidic phosphates is replaced by a different type of atom or a substituent, are useful as therapeutic agents and probes to elucidate mechanisms of enzymatic reactions. The internucleotidic phosphorus atoms of these oligonucleotides are ...
PubMed
The variation of atomic charges upon hydride addition to carbonylic compounds comprising: ketones, aldehydes, carboxylic acids, esters, and amides were studied using two different atomic partitionings: the QTAIM and the Hirshfeld scheme. The absolute charges for the electronegative atoms and those bonded to them ...
The compact measurement system for absolute densities of oxygen (O) atom has been developed employing a vacuum ultraviolet absorption spectroscopy (VUVAS) technique with a high-pressure micro-discharge hollow cathode lamp (MHCL) as a light source. The influences of self-absorption, emission line profiles of the MHCL, and the background ...
Two small rocket payloads containing atomic oxygen resonance lamps and detectors were flown during twilight and night conditions to measure atomic oxygen profiles from 70 to 130 km. The payloads each consisted of a closed, flowing rf excited, modulated, oxygen resonance lamp producing on the ...
... The effectiveness of atomic oxygen protective coatings relies upon the inherent atomic oxygen durability of the coating itself, and the number and ...
The exposure of silicones to atomic oxygen in low Earth orbit causes ... A comparison of the results of atomic oxygen interaction with silicones and ...
Diagnostic based modelling (DBM) actively combines complementary advantages of numerical plasma simulations and relatively simple optical emission spectroscopy (OES). DBM is employed to determine absolute atomic oxygen ground state densities in a helium-oxygen radio-frequency driven atmospheric pressure plasma jet. ...
The reactions of vinyl butyl ether and vinyl butyrate with atomic hydrogen and deuterium lead to addition at the terminal position of the olefins. This observation is consistent with the reactions carried out earlier with other olefins. Both of the absolute rates of addition to vinylbutyl ether and vinyl butyrate, in acetone and hexane, were measured at ...
... Accession Number : ADA211987. Title : Retrieval of Atomic Oxygen and Temperature in the Thermosphere. 1: Feasibility ...
... Descriptors : *ALKALINE EARTH METALS, *METALS, *OXIDES, *OXYGEN, *RECOMBINATION REACTIONS, ALUMINUM COMPOUNDS, ATOMS ...
... THE RELATIVE MATRIX DEACTIVATION RATES OF THE HIGHLY ENERGETIC SULFIDE-OXYGEN-ATOM PRECURSOR COMPLEX. ...
... Title : ON THE POSSIBILITY OF MEASURING ATOMIC OXYGEN AT THE HEIGHT OF 100 - 150 KM BY THE HEAT TRADUCER METHOD,. ...
... Title : Dioxododecaisopropoxytetratungsten. Oxygen Atom Abstraction from Acetone in Reactions with Hexaisopropoxyditungsten (M=M). ...
... Accession Number : AD0421572. Title : CATALYSIS OF OXYGEN ATOM RECOMBINATION,. Corporate Author : GENERAL ...
Techniques developed at the NASA Glenn Research Center to produce atomic oxygen in order to simulate
Atomic oxygen formation in a radio-frequency driven micro-atmospheric pressure plasma jet is investigated using both advanced optical diagnostics and numerical simulations of the dynamic plasma chemistry. Laser spectroscopic measurements of absolute densities of ground state atomic oxygen ...
This paper reports measurements of absolute scattering cross sections, differential in angle, for collisions of ground state oxygen atoms with He, N{sub 2}, and O{sub 2}. Data are presented for scattering of 0.5-, 1.5-, and 5.0-keV oxygen atome projectiles in the range of laboratory frame ...
The coplanar microscale atmospheric pressure plasma jet (?-APPJ) is a capacitively coupled radio frequency discharge (13.56 MHz, ~15 W rf power) designed for optimized optical diagnostic access. It is operated in a homogeneous glow mode with a noble gas flow (1.4 slm He) containing a small admixture of molecular oxygen (~0.5%). Ground state atomic ...
Absolute total cross sections for single electron capture by hydrogen-like ions of carbon, nitrogen, oxygen and fully-stripped oxygen ions from atomic hydrogen are being measured in the relative collision energy range of 0.01-20 keV/amu. Measurements are performed using a merged-beams technique with intensive ...
Atomic radicals such as hydrogen (H) and oxygen (O) play important roles in process plasmas. In a previous study, we developed a system for measuring the absolute density of H, O, nitrogen, and carbon atoms in plasmas using vacuum ultraviolet absorption spectroscopy (VUVAS) with a compact light source using an ...
Changes with temperature of x-ray intensities of the 001 reflections in ice and heavy ice are investigated. From these the amplitudes of thermal motion of oxygen and hydrogen atoms are determined separately. This can be accomplished since only hydrogen atoms contribute to the 004 reflection. The thermal amplitudes of the ...
At the heart of modern oxide chemistry lies the recognition that beneficial (as well as deleterious) materials properties can be obtained by deliberate deviations of oxygen atom occupancy from the ideal stoichiometry. Conversely, the capability to control and confine oxygen vacancies will be important to realize the full potential of ...
These films can be modified by additions of nitrogen, oxygen, and fluorine to produce coatings that are resistant to atomic oxygen erosion, ...
... Accession Number : AD0417929. Title : ABSOLUTE STABILITY OF CUBIC CRYSTAL STRUCTURES OF HEAVY RARE GAS ATOMS II,. ...
... Title : ON THE INFLUENCE OF RECOMBINATION OF ATOMS IN ... atoms of oxygen recombine in the instruments. ... the density in the instrument to that ...
The micro atmospheric pressure plasma jet (?APPJ) is a capacitively coupled rf discharge (13.56 MHz, �15 W transceiver power) developed, in particular, for optical diagnostics. The discharge is operated at a helium flow of about 1.4 slm with an admixture of oxygen (�0.5 vol.-%). In the effluent spatially resolved density distributions of the ground state ...
In order to characterize an inductively coupled plasma torch used in refining of metallurgical silicon, we have developed a spectroscopic method based on absolute emissivity measurements and Abel inversion. This method permitted to measure the concentrations of atomic hydrogen and atomic oxygen, which are among the ...
... theorists from the 'golden age' of nuclear strategy. His farsighted theories stated in The Absolute Weapon: Atomic Power and World Order,' are as ...
... has been used to measure the absolute total electron-helium-atom scattering cross ... with increasing energy to a minimum of about 10% below the ...
Absolute branching ratios for production of O(superscript 3P), O(superscript 1D), and O(superscript 1S) in the reaction of N(+) with O2 are measured using the flowing afterglow/visible chemiluminescence technique. The O(superscript 1S) product is monitore...
The rate parameters for the reaction of O(3P) with carbonyl sulfide, O(3P) + OCS yields CO + SO have been determined directly by monitoring O(3P) using the flash photolysis-resonance fluorescence technique. The value for k sub 1 was measured over a temper...
The characteristics of species in Kr/O{sub 2} mixture surface wave excited plasmas have been studied for clarifying the mechanism of plasma oxidation process. The absolute densities of the ground-state oxygen atom ({sup 3}P{sub j=0,1,2}) and the metastable oxygen atom ({sup 1}D{sub 2}) were ...
... Energy Oxygen Atom Chemistry Theoretical Studies of High Energy Oxygen Atom Chemistry The 2004 Air Force Office of Scientific Research ...
of 2 to more than a factor of 10, of atomic oxygen near the equator. The relative magnitude ... be used to determine atomic oxygen in the MLT [Russell ...
Atomic oxygen reaction with polymers causes erosion, which is a threat to ... polymers is the knowledge of the atomic oxygen fluence that the polymers were ...
ule moving into the natural neutral atomic oxygen ... Figure 2, atomic oxygen has the highest concentra- ... Atomic oxygen is highly reactive with polymeric ma- ...
... Title : Production of Pulsed Atomic Oxygen Beams Via ... to the formation of the atomic oxygen beam. ... a universal crossed molecular beams apparatus ...
Aug 29, 2007 ... Atomic oxygen, or oxygen broken into individual atoms by sunlight, doesn't typically exist on Earth. In low Earth orbit, however, these single ...
of the oxygen atoms at time t. Assume the rest position of the atoms are at x = ?d,0,d for the oxygen, carbon and oxygen atoms respectively. ...
E-print Network
atomic oxygen erosion yields. In LEO, atomic oxygen is an environmental durability ... different reactions and erosion rates. In an effort to improve the ...
Dec 3, 2004 ... developed for atomic oxygen exposure testing, has been investigated .... A soot covered feather was also included for atomic oxygen treatment ...
material removed per oxygen atom arriving) for FEP Teflon, polyethylene, and pyrolytic graphite with respect to Kapton. HN was performed in an atomic oxygen ...
The atom-beam recoil technique has been used to measure absolute total cross sections for the scattering of electrons by atomic and molecular oxygen at 22 energies between 0.5 and 11.3 eV, with additional data obtained up to 100 eV. In this method, a modulated electron beam cross-fires an atom ...
Feb 9, 2004 ... This radiation breaks typical oxygen molecules (O2) into free oxygen atoms. Those free atoms of oxygen (O) then join with molecular oxygen ...
of a carbon atom and M O the mass of an oxygen atom. We will model a vibration of the. bonds connecting the carbon atom to the oxygen atoms by connecting ...
Atomic oxygen plays a very important role in the upper atmospheric energy balance. Characterizing the global atomic oxygen distribution and its variabilities is key to our understanding of mesospheric thermal structure. Aboard the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) spacecraft, the ...
... POINTS OF LIQUID NITROGEN AND HYDROGEN. I. THE MEAN ATOMIC SPECIFIC HEATS AT 50 DEGREES ABSOLUTE OF THE ELEMENTS A ...
The effluent of a microscale atmospheric pressure plasma jet (?-APPJ) operated in helium with a small admixture of molecular oxygen (<1.6%) has been analyzed by means of two independent diagnostics, quantitative molecular beam mass spectrometry (MBMS) and two-photon absorption laser-induced fluorescence spectroscopy (TALIF). The atomic ...
