Kinetics and thermochemistry of ClCO formation from the Cl + CO association reaction
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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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The cosmic ray produced Ar-36/Ar-38 ratio measured in iron meteorites is about 0.65, but is not well determined for stone meteorites due to the common presence of trapped Ar or absorbed atmospheric Ar in bulk analysis. Almost all single-extraction measurements of stones give Ar-36/Ar-38 ratios intermediate between the trapped and air values of 5.3 and the expected cosmogenic value of about 0.65. The isotopic composition of Ar was measured for stepwise temperature release of both chondritic and melt portions of Chico. The Chico data suggest that for large chondrites, the cosmogenic Ar-36/Ar-38 ratio may well be higher than 0.65, and therefore the procedure of correcting bulk analysis results may underestimate the concentration of cosmogenic Ar-38. In this context we note that in analysis of many Antarctic chondrites observed that determined amounts of cosmogenic Ar-38 averaged about 13 percent too low in comparison to that expected from measurements of other cosmogenic species.
This video features scenes shot by the crew of onboard activities including Earth shots, middeck experiments, TDRS deploy, and other mission objectives.
The region of the UV between 500 and 1200 A is a rich one for the study of planetary and astrophysical targets. EUV atmospheric spectroscopy opens up an important window on ion and neutral nitrogen, oxygen, and noble gas emissions. In this document we describe the specific scientific background and motivations for this Venus EUV rocket observation along with experiment design and mission parameters.
The equilibrium structures, harmonic vibrational frequencies, dipole moments, and IR intensities of nitric acid, fluorine nitrate, and chlorine nitrate have been investigated by using the singles and doubles coupled cluster method that also includes a perturbational estimate of the effects of connected triple excitations, CCSD(T). A standard triple-zeta double-polarized basis set was utilized. The equilibrium geometries and vibrational spectra of HONO2 and ClONO2 are shown to be in excellent agreement with the available experimental data. The ab initio vibrational spectrum of FONO2 is also shown to be in excellent agreement with experiment. Unlike the FOOF and FON molecules, but similar to the cis- and trans-FONO molecules, FONO2 is shown to possess normal bond distances. The bonding in FONO2 is shown to be more similar to that in ClONO2 than that in HONO2, although there are still significant differences, especially in the partial atomic charges as deduced from Mulliken populations. This causes FONO2 to possess almost no dipole moment, which is very different to both HONO2 and ClONO2. By using large atomic natural orbital basis sets, CCSD(T) energies are computed for four isodesmic reactions in order to determine an accurate heat of formation for FONO2. Our best estimate for DELTA H(raised circle) (sub f,298) is 3.1 plus or minus 2.0 kcal/mol, indicating that the F-ONO2 bond energy is 31.3 kcal/mol.
This research developed and applied high-precision analytical methods (electron microprobe) to determine the major- and minor-element abundances (Si, Ti, A], Cr, Fe, Mn, Mg, Ca, Na, K) in three suites of Apollo 14 volcanic green glasses. Since the precision of these data was a factor of 5-10 better than previously published results, the data provided the strongest constraints yet achieved on the geochemical processes that operated at depths less than 400 kilometers inside the Moon. The results of this work were submitted to the 29th Lunar and Planetary Science Conference, formed the basis for a Master's Thesis, and were published in the top-tier geochemical journal. Additional high-precision data on the trace abundances of sodium (Na), sulfur (S), and potassium (K) in the Apollo 17 volcanic orange glasses (74220) were also acquired during this grant-period. These data show diffusion profiles within individual 200-micron diameter, glass spherules that were apparently generated during the fire-fountain eruption of this magma in the presence of a transient vapor phase. Although these results have not yet been published, publication is planned in 2001 after additional numerical modeling has been completed. This work has also catalyzed on-going collaborative work with Professor Timothy Grove (MIT) to analyze and understand the origin of the Apollo 15 volcanic green glasses. That work will be completed for publication in 2001.
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Rate constants for the reactions of OH with CH3C1, CH2Cl2, CHCl3 and CH3Br have been measured by a relative rate technique in which the reaction rate of each compound was compared to that of HFC-152a (CH3CHF2)and for CH2Cl2, HFC-161 (CH3CH2F).
We present R-matrix calculations of photoabsorption and photoionization cross sections across the K edge of Mg, Si, S, Ar, and Ca ions with more than 10 electrons. The calculations include the effects of radiative and Auger damping by means of an optical potential. The wave functions are constructed from single-electron. orbital bases obtained using a Thomas-Fermi-Dirac statistical model potential. Configuration interaction is considered among all states up to n = 3. The damping processes affect the resonances converging to the K-thresholds causing them to display symmetric profiles of constant width that smear the otherwise sharp edge at the photoionization threshold. These data are important for the modeling of features found in photoionized plasmas.
The Coiled Brine Recovery Assembly (CoBRA) project will result in a proof-of-concept demonstration for a lightweight, compact, affordable, regenerable and disposable solution to brine water recovery. The heart of CoBRA is an evaporator that produces water vapor from brine. This evaporator leverages a novel design that enables passive transport of brine from place to place within the system. While it will be necessary to build or modify a system for testing the CoBRA concept, the emphasis of this project will be on developing the evaporator itself. This project will utilize a “test early, test often” approach, building at least one trial evaporator to guide the design of the final product.
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LaP5O17Cl18 crystallizes in the monoclinic P2_1 space group. The structure is zero-dimensional and consists of two LaP5O17Cl18 clusters. La is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of La–O bond distances ranging from 2.51–2.71 Å. There are five inequivalent P sites. In the first P site, P is bonded in a tetrahedral geometry to one O and three Cl atoms. The P–O bond length is 1.48 Å. All P–Cl bond lengths are 1.99 Å. In the second P site, P is bonded in a tetrahedral geometry to one O and three Cl atoms. The P–O bond length is 1.48 Å. All P–Cl bond lengths are 1.99 Å. In the third P site, P is bonded in a tetrahedral geometry to one O and three Cl atoms. The P–O bond length is 1.48 Å. There is two shorter (1.99 Å) and one longer (2.00 Å) P–Cl bond length. In the fourth P site, P is bonded in a tetrahedral geometry to one O and three Cl atoms. The P–O bond length is 1.48 Å. There is two shorter (1.99 Å) and one longer (2.00 Å) P–Cl bond length. In the fifth P site, P is bonded in a tetrahedral geometry to one O and three Cl atoms. The P–O bond length is 1.48 Å. There is two shorter (1.99 Å) and one longer (2.00 Å) P–Cl bond length. There are seventeen inequivalent O sites. In the first O site, O is bonded in a distorted bent 150 degrees geometry to one La and one P atom. In the second O site, O is bonded in a distorted linear geometry to one La and one P atom. In the third O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.44 Å. In the fourth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.45 Å. In the fifth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.45 Å. In the sixth O site, O is bonded in a distorted single-bond geometry to one La and one P atom. In the seventh O site, O is bonded in a bent 120 degrees geometry to one La and one Cl atom. The O–Cl bond length is 1.51 Å. In the eighth O site, O is bonded in a water-like geometry to one La and one Cl atom. The O–Cl bond length is 1.50 Å. In the ninth O site, O is bonded in a distorted linear geometry to one La and one P atom. In the tenth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.44 Å. In the eleventh O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.45 Å. In the twelfth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.45 Å. In the thirteenth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. In the fourteenth O site, O is bonded in a distorted water-like geometry to one La and one Cl atom. The O–Cl bond length is 1.49 Å. In the fifteenth O site, O is bonded in a bent 150 degrees geometry to one La and one Cl atom. The O–Cl bond length is 1.49 Å. In the sixteenth O site, O is bonded in a distorted single-bond geometry to one La and one P atom. In the seventeenth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.45 Å. There are eighteen inequivalent Cl sites. In the first Cl site, Cl is bonded in a single-bond geometry to one P atom. In the second Cl site, Cl is bonded in a single-bond geometry to one P atom. In the third Cl site, Cl is bonded in a single-bond geometry to one P atom. In the fourth Cl site, Cl is bonded in a single-bond geometry to one P atom. In the fifth Cl site, Cl is bonded in a single-bond geometry to one P atom. In the sixth Cl site, Cl is bonded in a tetrahedral geometry to four O atoms. In the seventh Cl site, Cl is bonded in a single-bond geometry to one P atom. In the eighth Cl site, Cl is bonded in a single-bond geometry to one P atom. In the ninth Cl site, Cl is bonded in a single-bond geometry to one P atom. In the tenth Cl site, Cl is bonded in a single-bond geometry to one P atom. In the eleventh Cl site, Cl is bonded in a single-bond geometry to one P atom. In the twelfth Cl site, Cl is bonded in a single-bond geometry to one P atom. In the thirteenth Cl site, Cl is bonded in a tetrahedral geometry to four O atoms. In the fourteenth Cl site, Cl is bonded in a single-bond geometry to one P atom. In the fifteenth Cl site, Cl is bonded in a single-bond geometry to one P atom. In the sixteenth Cl site, Cl is bonded in a single-bond geometry to one P atom. In the seventeenth Cl site, Cl is bonded in a tetrahedral geometry to four O atoms. In the eighteenth Cl site, Cl is bonded in a single-bond geometry to one P atom.