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The effects of carbon monoxide and mixtures of carbon monoxide and hydrogen cyanide at different concentrations and times of exposure were studied in a pole-jump apparatus. The time to loose the avoidance and escape response for mice exposed to these atmospheres was obtained. Correlations to predict the loss as a function of dosage are presented.
Pupil responses to light are greatly influenced by initial pupil size. Small pupils, operating under photopic conditions, show tonic responses to step increases of light and high gains; thus the pupil is a good regulator of light. Large pupils, operating under mesopic or scotopic conditions show phasic responses, 'pupillary escape', and smaller gains: the pupil only transiently influences retinal flux. By using accommodation level to set the size of the pupil, the mechanism of the 'pupil size effect' is shown to be dependent on retinal light level only so far as retinal activity sets pupil size.
A two-stage process is presented to identify Io as the source of Na and K ions in the Io plasma torus. The Voyager I IRIS experiment recorded an SO2 abundance of 0.2 cm atm in the Io subsolar region, and further calculations determined that the S(+) and O(+) would have sufficient energy to penetrate the Io atmosphere and produce sputtering of surface atoms at a rate of 800 million/sq cm per sec. If K, Na, and S are present on the surface in cosmic proportions, then an evenly applied sputter distribution would produce the same abundances of sputtered Na and K as observed in the Na and K clouds around Io. Sputtered into the atmosphere, the ions undergo thermal Jean's escape and attain velocities of at least 2.6 km/sec. The sputtering ions are a factor of two greater on the Jupiter side than on the solar side, in agreement with asymmetries measured by the Voyager.
The escape rate of nitrogen from Mars is calculated to be 2.3 x 10 to the 5th per sec for low solar flux conditions and 8.9 x 10 to the 5th per sec for high solar flux conditions. The major source of energetic atoms is dissociative recombination of ground state and vibrationally excited N2(+) ions. The measured N-15/N-14 isotope ratio can be reproduced by postulating an early dense atmosphere during which little differentiation occurred.
It is shown in this work how to obtain the probabilities of photons escaping from a cold electron plasma environment after having undergone an arbitrary number of scatterings. This is done by retaining the exact differential cross section for Thomson scattering as opposed to using its polarization and angle averaged form. The results are given in the form of recursion relations. The geometry used is the semi-infinite plane-parallel geometry witlh a photon source located on a plane at an arbitrary optical depth below the surface. Analytical expressions are given for the probabilities which are accurate over a wide range of initial optical depth. These results can be used to model compact X-ray galactic sources which are surrounded by an electron-rich plasma.
A double crystal monochromator at the Stanford Synchrotron Radiation Laboratory is used to study the Si/SiO2 interface, using photon energies of hv = 1950-3700 eV. This photon energy range allows interfaces to be observed through oxide layers 50 A thick or more. Variations in electron escape depth and/or oxide density as a function of distance from the interface are observed over the entire kinetic energy range (100-3600 eV). These differences are attributed to a strained oxide layer near the interface.
Energy-independent first-flight transport kernels are evaluated for a spherical region with an R(-2) density distribution. The uncollided angular-flux distribution is obtained and integrated for a source distribution that is proportional to the density to give the uncollided emitted particle flux and current density. These are useful for the calculation of mass, energy, and momentum carried away by fast particles born in the medium. The data are relevant to estimate escape from weakly bound atmospheres such as comet comae, dilute circumstellar envelopes, and some unconfined laboratory plasmas.
Estimates of the abundance of sulfur, sodium and oxygen ions and neutrals observed by Voyager 1 in the plasma torus and neutral cloud associated with the Jovian satellite Io are used to investigate the physical characteristics of the Io atmosphere. Specific attention is given to two questions about the Io atmosphere: the necessity of an atmosphere to account for the supply of sulfur and oxygen observed in the plasma torus, and, if an atmosphere is necessary, the lower limit to such atmosphere. It is found that an SO2 atmosphere is most likely needed on Io as an intermediate buffer so that the sulfur and oxygen can be transported to the plasma torus. The minimum atmosphere needed for this process is calculated to be 1.4 x 10 to the -10th bar with an SO2 column density of about 10 to the 16th per sq cm and an SO2 surface density of about 1.2 x 10 to the 10th per cu cm. A complete list of all the atmospheric escape fluxes for Io is provided.
The service life evaluation of explosive devices used in a wide variety of aircraft escape systems is described. The purpose was to develop a service extension approach, supported by tests on candidate devices, to evaluate the effects of service, age, and degradation, and allow responsible, conservative, service life determinations. An overview is given on the recommended approach and experimental procedures for accurate service evaluations with test results on rigid and flexible explosive transfer lines, one-way transfers, and flexible linear shaped charges.
Both hydrodynamic calculations (Drury and Volk, 1981, and Axford et al., 1982) and kinetic simulations imply the existence of thermal subshocks in high-Mach-number cosmic-ray-mediated shocks. The injection efficiency of particles from the thermal background into the diffusive shock-acceleration process is determined in part by the sharpness and compression ratio of these subshocks. Results are reported for a Monte Carlo simulation that includes both the back reaction of accelerated particles on the inflowing plasma, producing a smoothing of the shock transition, and the free escape of particles allowing arbitrarily large overall compression ratios in high-Mach-number steady-state shocks. Energy spectra and estimates of the proportion of thermal ions accelerated to high energy are obtained.
Service life extension of explosive devices used in aircraft escape systems can achieve considerable savings. An overall approach is needed to challenge the logic of explosive component service extension from design to removal from service for evaluation. The purpose of the effort described in this paper was to develop a service-extension approach on explosive devices used in aircraft systems, supported by actual testing of representative candidate devices, to evaluate quantitatively the effects of service, age, and degradation, and allow responsible, conservative service life determinations. Evaluated were five explosive components: rigid and flexible explosive transfer lines, one-way transfers, flexible linear shaped charges, and initiation handles. The service extension approach generated in this effort is summarized by eight recommendations.
Chemical and functional tests yield conservative service-life estimates. Approach to extension of service lives of explosive devices in aircraft escape system developed, supported by testing of representative candidate devices to evaluate quantitatively effects of service, age, and degradation, and to enable responsible, conservative service-life determinations. Five types of explosive components evaluated: rigid and flexible explosive transfer lines; one-way transfers; flexible, linear-shaped charges; and initiation-handles. Extension of service in realistic manner provides both cost savings and increased system reliability.
The configuration and morphology of the plasma clouds in the ionotail of Venus (revealed by the Pioneer Venus Orbiter) are studied, and the rate of planetary ion escape, which may be associated with the dissipation and removal of the ionospheric plasma, is estimated. The data supplied by the Orbiter's instruments, the Orbiter electron temperature probe, the ion mass spectrometer, the neutral mass spectrometer, the magnetometer, and the plasma analyzer, are analyzed, and the results of the observations are discussed.
In order that magnetic flux be confined within the solar interior for times comparable to the solar cycle period it has been suggested that the bulk of the solar toroidal field is stored in the convectively stable overshoot region situated beneath the convection zone proper. Such a magnetic field, though, is still buoyant and is therefore subject to Rayleigh-Taylor type instabilities. The model problem of an isolated region of magnetic field embedded in a convectively stable atmosphere is considered. The fully nonlinear evolution of the two dimensional interchange of modes is studied, thereby shedding some light on one of the processes responsible for the escape of flux from the solar interior.
The polarization of an escaping terrestrial continuum radiation event that occurred on March 2, 1982, was determined using plasma wave measurements from the DE-1 spacecraft. The source of the radiation was determined to be located near the magnetic equator on the nightside of the earth at a radial distance of about 2.8-3.5 earth radii. Two meridional beams were detected, one directed north at an angle of about 20-30 deg with respect to the magnetic equator, and the other directed south at a comparable angle. Polarization measurements indicated that the radiation is right-hand polarized with respect to an outward directed E plane normal in the Northern Hemisphere and left-hand polarized in the Southern Hemisphere.
In the tractor-rocket seated-extraction candidate system for Space Shuttle Orbiter crew escape, the crewmember is pulled from his seat and away from the Orbiter via an elastic pendant, using a system of rails to guide the extraction trajectory through an opening on the window frame for flight deck crew and through the side hatch for the middeck crew. A three-body simulation has been developed to model the flight-mechanics aspects of the concept, where the three bodies are the astronaut (six DOF), the tractor rocket (six DOF), and the Shuttle Orbiter (three DOF); attention is given to crewmembers' clearance of the Orbiter structure and engine plumes.
Emergency escape system for aircraft and aerospace vehicles ejects up to seven crewmembers, one by one, within 120 s. Intended for emergencies in which disabled craft still in stable flight at no more than 220 kn (113 m/s) equivalent airspeed and sinking no faster than 110 ft/s (33.5 m/s) at altitudes up to 50,000 ft (15.2 km). Ejection rockets load themselves from magazine after each crewmember ejected. Jumpmaster queues other crewmembers and helps them position themselves on egress ramp. Rockets pull crewmembers clear of aircraft structure. Provides orderly, controlled exit and avoids ditching at sea or landing in rough terrain.
Space shuttle crewmembers have been equipped with a launch-entry crew escape system (LES) since the Challenger accident in 1986. Some crewmembers, wearing the new pressure suit, have reported breathing difficulties and increased effort to achieve the desired range of motion. This study was conducted to quantify the reported increased physical workloads and breathing difficulty associated with wearing the LES. Both veteran astronauts and centrifuge panel members were exposed to various + Gx profiles (including simulated shuttle launch) + Gx on the USAF School of Aerospace Medicine (USAFSAM) human-use centrifuge. Maximum heart rate data showed no increased workload associated with arm and head movement in the LES when compared to the flight suit/helmet ensemble (LEH). However, the LES did impose a significant increase in breathing difficulty beginning at +2.5 Gx which was demonstrated by a decrease in forced vital capacity and subjected questionnaries.