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The presence of oxygen in a gas is detected by contacting an article, such as a film, comprising poly(ethylenenaphthalene-dicarboxylate) with a gas and simultaneously exposing the article to ultraviolet light. The article is subsequently heated and the presence of oxygen in the gas is indicated by thermoluminescence.
Two strains of Bacillus subtilis were exposed to components of the ultraviolet spectrum in space. Both strains possess multiple genetic markers, and one of the strains is defective in the ability to repair ultraviolet damage. The T-7 bacteriophage of Escherichia coli was also exposed to selected wavelengths and energy levels of ultraviolet light in space. Preliminary findings do not reveal anomalies in survival rates. Data are not yet available on detailed genetic analyses.
Stellar ultraviolet light near 2500 A is attenuated in the earth's upper atmosphere due to strong absorption in the Hartley continuum of ozone. The intensity of stars in the Hartley continuum region has been monitored by the University of Wisconsin stellar photometers aboard the OAO-2 satellite during occultation of the star by the earth's atmosphere. These data have been used to determine the ozone number density profile at the occultation tangent point. The results of approximately 12 stellar occultations, obtained in low latitudes, are presented, giving the nighttime vertical number density profile of ozone in the 60- to 100-km region.
It was observed that quartz crystals from veins within a diabase dike of precambrian age from S.W. Africa contain organic particles which closely resemble, in detailed morphology, coacervates, proteinoid microspheres or fossil and recent microorganisms. The microphotospectrographs in visible and near-ultraviolet light of these minute particles revealed a strong absorption peak at the vicinity of 4000 A, which is indicative of lipids. Hydrothermal mineral from veins from a number of other localities proved to contain the biomorphic organic particles. The theoretical significance of these organic particles is discussed with reference to problems of origin of life.
Stellar ultraviolet light near 1500 A is attenuated in the earth's upper atmosphere due to strong absorption in the Schumann-Runge continuum of molecular oxygen. The intensity of stars in the Schumann-Runge continuum region has been monitored by the University of Wisconsin stellar photometers aboard the OAO-2 satellite during occultation of the star by the earth's atmosphere. These data have been used to determine the molecular oxygen number density profile at the occultation tangent point. The results of 14 stellar occultations obtained in low and middle latitudes are presented giving the night-time vertical number density profile of molecular oxygen in the 140-200 km region. In general, the measured molecular oxygen number density is about a factor of 2 lower than the number densities predicted by the CIRA 1965 model.
Photoemission diode standards for accurately measuring monochromatic ultraviolet light intensity (3000 A-1100 A) are described that are also blind to visible light. The standard uses an opaque photocathode of Cs2Te and is unique because of its combination of thinness (19 mm), high sensitivity, time stability, and uniformity of response. Design criteria, construction methods, and difficulties overcome in obtaining a stable, uniform, high yield photocathode responses are discussed. Cs2Te is discussed in terms of a model for high yield photoemitters.
Details are presented of flow visualization techniques developed during wind tunnel test IA-52 conducted in a 14 x 14 inch trisonic wind tunnel. Testing was conducted from Mach = 0.9 to 5.0 on the orbiter alone and integrated vehicle configurations. Thin film oil paint and ultraviolet light sensitive oil applications were used on a .004 scale model vehicle. Test results presented are in the form of black and white photographs taken after the completion of a test run.
A class of polymers is provided, namely, poly(diarylsiloxy) arylazines. These polymers have a basic chemical composition which has the property of stabilizing the optical and physical properties of the polymer against the degradative effect of ultraviolet light and high temperatures. This stabilization occurs at wavelengths including those shorter than found on the surface of the earth and in the absence or presence of oxygen, making the polymers of the present invention useful for high performance coating applications in extraterrestrial space as well as similar applications in terrestrial service. The invention also provides aromatic azines which are useful in the preparation of polymers such as those of the present invention.
The method of photographic subtraction, which superposes positive and negative photographs taken with the analyzer rotated through 90 deg, is used to analyze polarization photographs of Venus, Jupiter, Saturn, and the moon. For Venus, near 90 deg phase angle, variation in polarization in ultraviolet light appears to correspond generally with the position of the cloud markings. The northern hemisphere of Saturn shows higher polarization in blue light than does the rest of the planet. The polarization of the moon is shown to deviate significantly from Umov's law for reciprocity of polarization and reflectivity in certain regions.
The violet solar cell has been submitted to a flight qualification program. The tasks included in this program were: to define the violet cell's electrical output from -100 C to +100 C; to determine the violet cell's degradation under 2 MeV, 1 MeV and .3 MeV proton irradiation, under a high humidity environment and under ultraviolet light; to thermal cycle two similar modules of violet cells; to flight qualify a full size violet cell panel for the IMP-J flight; and to obtain a primary balloon-flown standard of the violet cell type. The results of these tests demonstrate that the violet cell is fully qualified for space flight use with no further development work. The tests show that the violet cell offers a power increase of at least twenty-one per cent over presently available commercial cells.
The likelihood of biologically contaminating a planet by an atmospheric probe has a low probability of occurring if the probe is kept biologically clean during terrestrial operations and if the structure remains in tact until the planets life zone is completely penetrated. High standards of cleanliness, monitoring and estimating for remedial actions must be maintained in a probe program. It is not a foregone conclusion, however, that heat sterilization needs to be employed. The use of several techniques having a good potential for lower probe costs are available and appear adequate to render a probe sterile within acceptable bounds. The techniques considered to be satisfactory for minimizing microbial load include: (1) combined heat (at 95-105 C) and gamma radiation; (2) short term heating at 105 + or - 5 C to inactivate all vegetative microbes; (3) irradiation routinely by ultraviolet light; (4) wiping by a bactericidal agent with or without a penetrant; and (5) cleanliness alone.
The generation of tunable visible, infrared, and ultraviolet light is examined, along with the control of this light by means of novel mode-locking and modulation techniques. Transient mode-locking of the Nd:YAG laser and generation of short tunable pulses in the visible and the alkali metal inert gas excimer laser systems were investigated. Techniques for frequency conversion of high power and high energy laser radiation are discussed, along with high average power blue and UV laser light sources.
Texts of high-energy multicharged particle, ultraviolet light, and galactic irradiation fluxes on exposed biological specimens aboard Apollo 16 are described. Passive nuclear track detectors, passive dosimeters, and thermoluminescent dosimeters, respectively, were used for the measurements. Biological phenomena studied ranged from lipolytic alpha toxin production in Bacillus thuringiensis to animal tissue invasion (of human hair by Trichophyton terrestre). Fluxes observed were lower than those recorded by detectors located in the Biostack and in the passive personnel dosimeters worn by the astronauts, suggesting a greater average shielding in the latter two environments.
System is capable of detecting ultraviolet light emitted by match size flame at distance of 10 ft. System is not affected by high energy or particulate radiation and is therefore particularly suited for applications around nuclear plants and X-ray equipment.
A new class of polymers is provided, namely, poly (diarylsiloxy) arylazines. These novel polymers have a basic chemical composition which has the property of stabilizing the optical and physical properties of the polymer against the degradative effect of ultraviolet light and high temperatures. This stabilization occurs at wavelengths including those shorter than found on the surface of the earth and in the absence or presence of oxygen, making the polymers useful for high performance coating applications in extraterrestrial space as well as similar applications in terrestrial service. The invention also provides novel aromatic azines which are useful in the preparation of polymers such as those described.
The 1956, 1971, and 1973 major dust storms on Mars affected the apparent contrast and extent of the northern polar hood. A survey of photography from seven apparitions indicates that this seasonal feature is consistently prominent and identified in the absence of major storms throughout half of the Martian year. During the 1956 dust storm, the hood was not seen for a period of over one month on Lowell photographs. The effects of a storm are also seen in 1971 International Planetary Patrol photographs; the hood quickly became faint and tenuous even in ultraviolet light, which normally shows it as very bright. Patrol photographs of 1973 cover the complete progression from a prominent and extensive hood before the storm, to an intermittent disappearance at the height of the storm, to the subsequent return of a normal hood as the storm died out.
A review is presented of the current state of knowledge concerning the emitted flux distributions of Ap stars and their ultraviolet photometric variability especially as it relates to photometric and spectrum variability observed in the visible. A table of Ap stars observed in the ultraviolet from space vehicles is presented along with a graph which shows the observed flux distributions, normalized to unity flux at 3320 A, for the Si star theta Aur and for the normal stars 134 Tau and gamma UMa. Attention is given to ultraviolet color indices and ultraviolet light curves for variable Ap stars.
Spectral scans of the Ap star Epsilon UMa made with the Copernicus satellite show strong line blanketing from profuse Cr II and Fe II lines. In the spectral region covering 1900 to 3000 A, about 500 lines are present which suppress the apparent continuum by at least 15-30%. An accurate line-identification list is compiled showing Eu II present in addition to Mn II and Ni II. The identification of Eu II, however, rests on very stringent identification limits for Fe II. If these are relaxed, the existence of Eu II is dubious. There are no broad features in this spectral region which would suggest strong photoionization discontinuities by metals, but one feature near 2137 A might contain the photoionization edge due to Cr I 5S lying 0.94 eV above the ground level. However, a significant correlation between the line-blanketing strength and the amplitude of the OAO-2 ultraviolet light curves was found such that both monotonically increase in the same proportion toward shorter wavelengths. This gives additional strength to the suggestion that variations in the metal line-blanketing cause the observed photometric variations.