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Experimental aging of Arctic diesel, gasoline, motor oil, benzene, and petroleum ether in marine simulated environment failed to produce any tar-like material. Bunker C produced tars quickly. Southern Louisiana crude oil failed to form tars even when asphalt was added to the solution before aging. Presumably some combination of surface energy and mutual solubilities prevents tar formation in this case. The effect warrants further investigation. Aging experiments seem to show that asphaltenes form from other components during aging. Analyses of marine tars demonstrate the value of separating tar components and analyzing the fractions separately. Presence of particulate iron in some marine tars strongly supports the hypothesis that man's activities are involved in their formation. Attached fouling organisms appear to be an important agent in removing floating tar from the sea surface.

A study was undertaken to develop a rapid, efficient method for identifying the source of spilled oil. Fifty-seven different petroleum products were weathered under controlled conditions in laboratory simulators. Samples were taken periodically and examined by a variety of analytical techniques. The analytical methods were graded on their abilities to (1) classify petroleum products as to generic type and (2) identify the actual source of the spilled oil. Four types of analyses were identified as being especially useful: thin-layer chromatography, infrared fingerprinting, gas chromatographic fingerprinting and liquid-liquid chromatography. The application of these techniques is discussed in detail and examples are given. By use of a combination of these four technques all oils studied in this project could be uniquely identified. (Author)

The report concerns the development of high-vacuum liquid-helium cooled circular-variable filter spectrometers. These spectrometers have been successfully used in rocketborne applications to make in situ measurements of the overhead spectral radiance, as a function of rocket height, of the atmospheric emission species in the long wavelength region of the infrared. This research led to the advancement of the state-of-the-art in such aerospace infrared measurements and in several related areas such as the detector- preamplifier interface and cold bearing design. A total of five rocket flights were conducted which resulted in measurements of the overhead radiance, as a function of rocket altitude between 45 and 200 km, of the atmospheric emissions in the 7 to 24 micrometer range of the infrared.

The aim of this research has been to refine the physics associated with the energy levels involved at the interface between silicon and silicon dioxide as exemplified in an n-channel MOSFET structure. Demonstration of the photoresistive response of devices to radiation resonant with energy levels in the inversion layer has allowed characterization of a voltage tuneable infrared detector-spectrometer. Operating at 4.2K, typical devices have continuous tuneability from 8 mev (about 150 micrometers) to 30 mev (about 40 micrometers), a band width of approximately 1 mev, a response time of 0.00025 seconds and a noise equivalent power (NEP) of approximately 10 to the -11th power watts. Outlines for methods of improvement in terms of band range, band width and noise equivalent power have been obtained.

Until recently, no instrument displayed the sensitivity, stability, and portability necessary for on-site field analysis of trace contaminants in aviator's breathing oxygen (ABO). A solid-state portable infrared gas analyzer became commercially available in 1971, which led to development of an instrument package capable of analyzing ABO at the base level. Procedures for field analysis of ABO are given as a guide for Air Force personnel using the ABO contaminant detector system developed by USAFSAM. (Author)

The results of a round robin of measurements for the purpose of standardizing infrared directional emittance and reflectance apparatus in three laboratories are presented. Polarizers were incorporated in two of the devices, which have dispersing monochromators in their optical paths. Samples of bare polished fused silica as well as gold evaporated on polished nickel were the basis for the calibration. Their directional polarized properties were independently computed using published optical constants, and are presented here. (Modified author abstract)

The report describes work concerning the design of a liquid Helium cooled infrared spectrometer for an Aerobee sounding rocket payload. The flight is designed to study the diffuse radiation from the Ecliptic and Galactic planes. The designs of the Dewar and electronics systems are not described here. The telescope will be an f3 7-inch aperture Cassegrain system. (Modified author abstract)

An Astrobee D rocket (A30.205-4) was launched at Poker Flat, Alaska, on 9 March 1972 at 1052 hours UT during a condition of Class IBC2 post-breakup auroral display. A near-zenith spectral radiance profile was obtained from 48.5 km to an apogee of 91.9 km on ascent, and from 91.9 km down to about 84.7 km on descent, using a circular variable-filter spectrometer. About 268 spectral scans were obtained during flight, covering the range from 1.4 to 5.0 micrometer at a resolution of about 4 per cent. The dominant emission feature was at 4.3 micrometer, which is attributed to the CO2 nu(3) fundamental. The upward-viewed spectral radiance appeared to range from about 45 MR/micrometer at 48.5 km to less than 2 MR/micrometer at 92 km. A volume-emission-rate/altitude profile for the nu(3) fundamental of CO2 is presented. The profile is based on a simple LTE model and neglects radiation transport. As a result, the model cannot be compared directly with the data. A more complete analysis of the problem is in progress. (Author)

The preparation and evaluation of two infrared interferometer spectrometers for the balloon borne measurement of atmospheric radiance is described. The flights of 5 April 1962 and 2 August 1962 showed agreement with the theoretical data computed from the available temperature, pressure and dew point profiles. Auxiliary sys tems were built, tested and flown in these flights. Comparison spectral runs and evaluations were conducted with independent laboratories. A procedure for calibration was developed and an evaluation of the precision and accuracy of the instrument was undertaken. Several possible improvements for future measurement programs were evaluated and proposed recommendations are included.

The theory and operation of an interferometricmodulation order-separator for a far infrared spectrograph is described.

Laboratory studies were conducted about the spatial and spectral distribution of rocket plume radiance at simulated altitudes. Motors of 150 to 200 lb thrust were operated at sea level and at pressures equivalent to approximately 50,000 and 100,000 ft. The propellant combinations studied were gasoline/oxygen, RP 1/OXYGEN, JP 4/oxygen, UDMH/N2O4 and aluminized solid propellant. A traversing rocket technique was employed which permitted simultaneous observation of a number of radiometric and spectrometric properties of a common area of the plume. The graphical presentations of these data are interpreted on a qualitative and semi-quantitative basis.

The principal instruments and facilities are described with special emphasis on new construction or modifications. This equipment includes two high dispersion grating spectrographs, two types of patrol spectrographs, ground- based, aircraft borne and balloon-borne infrared spectrometers, a scanning spectrometer for the visible and ultra violet regions with memory unit, two types of photometer for the study of twilight alkali emissions, a Michelson interferometer for the near infrared region and a temperature-measuring photometer for the measuring of auroral rotational temperatures. Also described are facilities for producing specialized interference filters, a source for the Vegard-Kaplan bands, intensity standards for absolute brightness measurements of aurora and a system for obtaining all-sky photographs through interference filters. There is also a brief description of two rocket borne photometers which are under development. Twilight airglow and dayglow measurements, observations of auroral emissions, of the night airglow and of auroral temperatures are discussed. A study is described of the possibility of measuring atmospheric temperatures using the vibrational ratios of N(2) bands. New quantitative measurements of the Vegard-Kaplan bands in the second positive bands of N(2) with the photo electric scanning spectrometer and memory are described.

A rocket-borne infrared spectrometer employing the principles of mock interferometry is described. Development work centered around two main problems: (1) Design of a mechanical drive unit that would yield a "linear" reticle drive; (2) Design of an optical correction system to correct the field curvature produced by off-axis rays. The first of these problems was eventually solved but no good solution to the second problem was discovered. The off-axis imaging problem can be ameliorated by using small entrance and exit apertures, but this limits throughout and resolution. The problem is not felt to be inherently insoluble and further work to devise an optical correction system is recommended.

Samples of condensed ring hydrocarbons ranging in size from benzene to dinaphthocoronene are being analysed after irradiation in the pile. The determination of primary importance is that for the amount of unchanged material, and this is being done by direct infrared analysis. In addition, the identification and analysis of the irradiation products are being attempted, using chromatographic techniques to isolate these products prior to identification by infrared analysis. Direct infrared analysis of irradiated samples of benzene, naphthalene, anthracene, phenanthrene, l,2-benzanthracene, pyrene, and 1,2, 5,6-dibenzanthracene has been completed and some work has been done to determine the identity of the compounds produced from them by the irradiation process. When the materials are available, it is planned to irradiate and analyse samples of chrysene, perylene, triphenylene, coronene, dibenzocoronene, and dinaphthocoronene. jg p.4

The technical note is one of a series that provides brief descriptions of scientific programs investigating the physics and chemistry of the upper atmosphere under normal and disturbed conditions in support of the High Altitude Effects Simulation (HAES) program of the Defense Nuclear Agency. In the absence of actual nuclear testing in the atmosphere a number of experiments are being carried out both in the laboratory and in the field to determine a sufficient number of parameters to characterize the environment and its reactions in a suitable model. This technical note describes one of these experiments. The circular variable filter (CVF) infrared spectrometer is one of the principal instruments used in rocket-borne experiments to measure auroral infrared emissions. The spectrometers described were developed by Utah State University and include both liquid nitrogen cooled short wavelength infrared and liquid helium cooled long wave infrared spectrometers. A brief description is also given of the CVF spectrometer experiments flown in the ICECAP 73 rocket series launched from Poker Flat, Alaska in March 1973.

The report describes the theory, details and performance of the laboratory prototype of a small-scale Fourier spectrometer to measure the absolute spectral intensity of the radiation from the Earth or other planets in the 10 to 40 micrometer range from aircraft, balloons, rockets or satellites. (Author), Trans. of Akademiya Nauk SSSR. Fizicheskii Institut, Preprint-189 p1-31 1969.

The far infrared portion of the electromagnetic spectrum has, until very recently, been the least accessible to experimentalists in the field of plasma diagnostics. Within the last decade, the availability of fast, sensitive detectors, known calibration sources, and rapid advancement in the field of fusion plasma research, have made the far infrared region quite viable and attractive in diagnostics. By far the most versatile and useful instrument in this area is the vacuum grating spectrometer. Thus a far-infrared spectroscopic system, the heart of which is a vacuum grating spectrometer, was built for plasma spectroscopy studies on the Texas Tokamak. The work described here specifies the system and defines some of the more important operating characteristics of the spectrometer. (Author)

The instrumentation used to obtain data for the purposes of an investigation into the use of passive, optical techniques for arms control inspection of rocket testing is described. Three distinct systems were used. The first employed a single detector infrared spectrometer; the second was a prototype multiple detector spectroscopic system and the third was an improved, operational version of the multiple detector system. Common to all three were documentary and engineering sequential cameras. Included in the report is a detailed discussion of the three systems as well as an explanation of the spectral data processing procedures. (Author), See also Volume 1, AD-701 255.