Showing papers by "Ames Research Center published in 1969"
TL;DR: In this paper, a numerical method for time dependent compressible Navier-Stokes equations applied to axisymmetric flow field produced by hypervelocity impact, examining viscous effects is presented.
Abstract: Numerical method for time dependent compressible Navier-Stokes equations applied to axisymmetric flow field produced by hypervelocity impact, examining viscous effects
1,156 citations
01 Apr 1969
TL;DR: In this article, the authors reviewed the use of pilot rating scales and their use in assessing aircraft handling qualities and proposed a new definition of handling qualities, emphasizing the importance of factors that influence the selection of a rating other than stability and control characteristics.
Abstract: : Pilot rating scales and their use in assessing aircraft handling qualities are reviewed historically, and objections that have been raised to limitations of earlier scales are considered in the development of a revised scale. Terminology used in the evaluation of handling qualities is reviewed and new definitions are proposed to improve communication and international understanding. Of particular significance is the new definition of handling qualities, which emphasizes the importance of factors that influence the selection of a rating other than stability and control characteristics. The experimental use of pilot rating is discussed in detail, with special attention devoted to (1) clarifying the difference between mission and task, (2) identifying what the rating applies to, (3) considering the pilot's assessment criteria, and (4) defining the simulation situation. The important elements of the report are then summarized in a suggested 'Briefing Guide,' designed for guidance in planning and executing handling qualities experiments.
978 citations
TL;DR: “Human imagination is the source of the greatest triumphs of science, technology, art, and philosophy, and the authors must be careful not to cripple its exercise by arbitrary restrictions.
Abstract: “Human imagination is the source of the greatest triumphs of science, technology, art, and philosophy. We must be careful not to cripple its exercise by arbitrary restrictions. It gives us our preeminence over the brutes.” C. J. Herrick 1956 The Evolution of Human Nature
494 citations
TL;DR: The results help to explain how the lung maintains oxygen and carbon dioxide transfer in the face of ventilation-perfusion ratio inequality and may be useful in characterizing the degree of ventilation and perfusion inequality in real situations.
290 citations
TL;DR: Results are presented of an experiment to determine extraterrestrial solar spectral irradiance at the earth's mean solar distance within the 300-2500 nm wavelength region, with absolute accuracy of approximately +/-3% over most of the measurement range.
Abstract: Extraterrestrial solar spectral irradiance at earth mean solar distance within 300 to 2500 nm wavelength region, from NASA CV-990 aircraft research flights
281 citations
TL;DR: Highly purified cathepsin C was characterized as a Cl--activated dipeptidyl aminopeptidase of broader specificity than hitherto known for the bovine spleen enzyme, and substrate specificity characteristics comparable to its hydrolytic activity on amides, β-naphthylamides, and esters.
215 citations
TL;DR: Interplanetary magnetic fields from Explorer 33 magnetometer relationship to surface geomagnetic variations emphasizing unified view as discussed by the authors, showing that the Earth's magnetic field can be represented by a unified view.
209 citations
TL;DR: In this paper, a computer program was used to predict spectra from electronic transitions of diatomic molecules and atoms, noting line intensity distribution by Voigt profile, based on spectral properties.
Abstract: Computer program to predict spectra from electronic transitions of diatomic molecules and atoms, noting line intensity distribution by Voigt profile
176 citations
01 Jan 1969
140 citations
TL;DR: Aerodynamic coefficients from observed motion of body in flight, eliminating need for closed form solutions by employing numerical solutions to equations of motion were derived by as mentioned in this paper, where they were used to eliminate the need for a closed form solution.
Abstract: Aerodynamic coefficients from observed motion of body in flight, eliminating need for closed form solutions by employing numerical solutions to equations of motion
132 citations
TL;DR: The condensation of amino-acids in aqueous solutions using various “prebiotic” condensing agents, such as cyanamide1–3, cyanoguanidine4 and dicyanamide5, is reported.
Abstract: Peptide formation during glycine reaction with linear polyphosphates and cyclic metaphosphates, considering prebiotic synthesis
TL;DR: Transmission of Alfven waves through earth bow shock based on hydromagnetic shocks theory, discussing amplitude amplification as mentioned in this paper, discussed amplitude amplification and amplitude amplification of the earth bow wave.
TL;DR: In this article, an organic synthesis by electrical discharge in simulated Jovian atmosphere is described, noting appearance of orange-red cyanogen-ammonia polymer nonvolatile fraction.
TL;DR: A crater 30 cm in diameter and 4.4 cm in depth was created by the impact of an aluminium sphere with a homogeneous granite target as discussed by the authors, the volume excavated was 748 cm3, the mass ejected 1933 g. The crater geometry is compared with previous laboratory experiments.
Abstract: A crater 30 cm in diameter and 4.4 cm in depth was produced upon impact of an aluminium sphere with a homogeneous granite target. The volume excavated was 748 cm3, the mass ejected 1933 g. The crater geometry is compared with previous laboratory experiments. Mineralogical investigations revealed that shock induced, microscopic fracturing is lowest in the direction of uniaxial compression, followed by a 45° profile. Due to reflections of stress waves at the free surface, the horizontal profile displayed the highest fracture index. Kinking of biotite was very common in samples close to the crater walls (≈ 50 kb). However it faded out at a distance which corresponds to approximately 10 kb. This seems to be the lower pressure limit for the formation of kink bands under shock conditions.
TL;DR: The problem of identifying and characterization of mixtures of sugars by gas-liquid chromatography (GLC) has posed considerable difficulty since the advent of the technique1,2 as mentioned in this paper.
Abstract: IDENTIFICATION and characterization of mixtures of sugars by gas–liquid chromatography (GLC) have posed considerable difficulty since the advent of the technique1,2. The principal problems have been: (a) the isomerism of the sugars, giving several peaks for each sugar, and (b) the lack of sugar derivatives with sufficient volatility and stability to avoid overlong retention times and degradation during chromatographic separation.
TL;DR: An analytic model of the human left ventricularle is presented, which incorporates the three-dimensional shape of the left ventricle and the effects of ventricular wall thickness, which resembles a thick-walled ellipsoid of revolution.
TL;DR: Atmospheric oxygen A band individual rotational lines intensities and half widths measurements were collected in this paper. But the results showed that the rotational line intensities varied with the altitude.
Abstract: Atmospheric oxygen A band individual rotational lines intensities and half widths measurements
TL;DR: Evidence derived from this study is used to support a common identity for dipeptidyl aminopeptidase I and the "glucagon-degrading enzyme" of liver.
TL;DR: Aerodynamics of bodies of revolution in nonplanar motion using nonlinear functional analysis of moments for motion about center of gravity is described in this paper. But the analysis is restricted to a single body of revolution.
Abstract: Aerodynamics of bodies of revolution in nonplanar motion using nonlinear functional analysis of moments for motion about center of gravity
TL;DR: The data presented suggest that it is possible to make meaningful comparisons between EEG records obtained with a single presentation of the stimulus and the average evoked potential.
01 Jan 1969
01 Oct 1969
TL;DR: Halobacterium cutirubrum extracts exhibit no menadione reductase activity in the absence of salt; activity increases with salt concentration to a maximum at 2 m or higher concentrations of sodium chloride, and enzyme activity lost at low salt concentrations can be restored by adding 2 m NaCl.
TL;DR: In this article, the authors present a quantitative interpretation of three dimensional weakly refractive phase objects using holographic interferometry, determining the index of refraction of the phase objects.
Abstract: Quantitative interpretation of three dimensional weakly refractive phase objects using holographic interferometry, determining index of refraction
TL;DR: A main branch of electron transport including a flavoprotein, reduced by DPNH, and a second branch consisting of flavoproteins and cytochrome b(559), reduced byDPNH and succinate are suggested, which join at the c-type cytochromes.
TL;DR: In this paper, meteorites pigments were identified as porphyrins for extraterrestrial life evidence, using sample analyses of Orgueil, Murray, Cold Bokkeveld and Mokoia carbonaceous chondrites.
01 Jan 1969
TL;DR: In this article, a global morphology of electron density distributions in the topside ionosphere during sunspot minimum as deduced from Alouette I and II ionograms is presented.
Abstract: A global morphology of electron density distributions in the topside ionosphere during sunspot minimum as deduced from Alouette I and II ionograms is presented. Graphs are shown illustrating the variations of electron density with altitude (400 to 3000 km), dip latitude (±90°), local time (24 hours), and season (December and June solstices; equinox) for both quiet and disturbed geomagnetic field conditions. "Average" daytime and nighttime electron density distributions, based on the analysis of large quantities of Alouette I quiet-time data, are presented for the lower altitudes (less than 1000 km) and for low and middle dip latitudes for each season. Large-scale anomalous features are summarized and discussed with respect to their bottomside counterparts where such exist. Small-scale effects and physical explanations for the topside ionosphere behavior are discussed in companion papers.
TL;DR: Immunodiffusion showed that antiserum to rat prolactin cross-reacted strongly with hamster and weakly with mouse pituitary extracts, but not with extracts from pigeon, pig, or guinea pig.
Abstract: Prolactin was isolated from fresh, whole rat pituitary glands by the following procedure: 1) sequential extraction to remove other hormones, 2) extraction of prolactin with 60% ethanol at pH 9.5 and precipitation with 80% ethanol at pH 6, 3) filtration on Sephadex G-100 at pH 9, and 4) chromatography on DEAE-cellulose with gradient elution at pH 8. The yield was about 1 mg/g of glands at a potency of 28 IU/mg by the local crop assay and 11 IU by the systemic assay. The preparation was 95% homogeneous by electrofocusing in 2M urea and showed a pI =5.46. Analysis by sedimentationequilibrium gave a mol wt of 21,600. Best- analysis of the amino acid composition gave mol wt of 22,500; only 2 residues of methionine were present. Leucine constituted the amino terminus. Immunodiffusion showed that antiserum to rat prolactin cross-reacted strongly with hamster and weakly with mouse pituitary extracts, but not with extracts from pigeon, pig, or guinea pig. Complement fixation was absent when antiserum to rat prolac...
TL;DR: Naatanen's comments on Donchin and Cohen's study of selective attention seem to derive from a failure to appreciate the relationship between the negative shifts in cortical potentials reported by Naatanen, and Grey Walter's CNV.
Abstract: Naatanen's comments on Donchin and Cohen's study of selective attention seem to derive from a failure to appreciate the relationship between the negative shifts in cortical potentials reported by N...
01 Jan 1969
TL;DR: Subsonic lifting surface theory including leading edge, discussing singularities in solution of integral equation for determination of aerodynamic properties as mentioned in this paper, discussed singularity in solution for determining aerodynamic property.
Abstract: Subsonic lifting surface theory including leading edge, discussing singularities in solution of integral equation for determination of aerodynamic properties