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Of six samples from boulder 1 at Station 2, four contain a unique meteoritic component, which is attributed to the Crisium projectile. The other two samples are meteorite free, igneous rocks: an unusual, alkali- and Ge-rich pigeonitic basalt, and an alkali-poor norite of unexceptional trace element chemistry.
Samples of ASTM type A jet fuel were analyzed for trace-element content by instrumental neutron activation techniques. Forty-nine elements were sought. Only ten, aluminum, gold, indium, lanthanum, titanium, vandium, barium, dysprosium, tellurium, and uranium, were observed at levels above the detection limits encountered; of these only aluminum, titanium, and barium were present at concentrations greater than 0.1 ppm. Estimates of exhaust gas concentrations are made, and the ambient contribution at or near airports is calculated by using the Los Angeles International Airport dispersion model. It is shown that the ambient contribution is about an order of magnitude below typical urban levels for virtually all elements sought.
An experimental investigation of catalytic oxidation of trace levels of methane in oxygen was conducted in a tubular reactor. Two noble metal solid catalysts were explored: a 1-percent platinum on gamma alumina and a 0.5-percent rhodium on gamma alumina. For each catalyst the activity was determined as a function of temperature, pressure, space velocity, and methane concentration. The rhodium catalyst was considerably more active than the platinum catalyst. For each catalyst mass transfer had a pronounced effect upon activity at low space velocity.
The PDS-1010G microdensitometer is run under the control of a PDP-11 program called TRACE. This program gives the operator vary flexible control over the machine functions. Most commands are passed to the computer through either the Tektronix 4010 terminal or the teletype, as selected by the position of the LOCAL/LINE rocker switch above the 4010 keyboard. (LINE places the 4010 in control; LOCAL transfers control to the teletype. In general, the teletype is used when the operator desires a permanent record of the operator-computer dialogue.) A small number of control functions are requested by setting switches on the computer front panel.
The factors that affect the preferred positions of cations in ionic solid solutions were investigated utilizing vibrational spectroscopy. Solid solutions of the sulfate and chromate ions codoped with La(+3) and Ca(+2) in a KBr host lattice were examined as a function of the polyvalent cation concentration. The cation-anion pairing process was found to be random for Ca(+2), whereas the formation of La(+3)-SO4(-2) ion pairs with a C2 sub v bonding geometry is highly preferential to any type of La(+3)-CrO4(-2) ion pair formation. The relative populations of ion pair site configurations are discussed in terms of an energy-entropy competition model which can be applied to the partition of trace elements during magmatic processes.
Description of three experiments involving the injection of barium ions into magnetic flux tubes with the aid of high-explosive shaped charges with hollow conical liners of barium metal. In these experiments (called Alco, Bubia, and Loro, respectively) the explosive charges were detonated at altitudes above 500 km, producing jets of barium plasma with initial velocities ranging from 8 to 20 km/sec. The most interesting result of the experiments, which were carried out near L = 1.24 and were successful in tracing an entire field line some 7000 km to the conjugate ionosphere, was the observation that for Loro and probably Alco the direction and rate of drift of the two ends of the field line were identical, whereas those for Bubia differed significantly. In the case of the Bubia event significant differences in magnitude and direction at the conjugate points are noted, which lead to the conclusion that the field line could not have been equipotential during the interval of observation.
Analyses for major elements, REE, Co, Cr, Cs, Ga, Hf, Ni, Rb, Sc, and Zn have been done on samples of Apollo 16 rocks 60025, 60335, 64455, 65015, 67075, and 67629 and on fines 60601, 61221, 61241, 64501, 65701, 67601, and 69941. FeO, Na2O, REE, Co, Cr, Hf, and Sc have been determined in four 4-5 mg chips from 65015 and 20 individual, 2.5-9.5 mg fragments from 65702. It appears that trace element characteristics of small fragments are similar to those of larger rocks. No simple mixing relationship was found among KREEP basalts, VHA basalts, anorthosites, fines, and meteorites. Balances could not be simultaneously achieved for Al2O3 and LIL elements, using analyzed samples as end members for mixing models. Most samples analyzed have negative Eu anomalies, in contrast to the positive anomalies expected for plagioclase cumulates. Most samples may be derived from LIL-rich liquids that flowed into highland valleys.
Two types of highland terrain appear to be present at the Apollo 16 landing site. The Plains Formation called Cayley is ubiquitous and blankets even those regions that were presumably a part of the mountainous Descartes Formation. The second type of terrain is that associated with the ejectae from North and South Ray craters. The stratigraphy sampled by the ejectae underlays the Cayley layer as characterized above and may permit a redefinition of Descartes Formation as that which underlays the smooth Plains deposits. These conclusions are based on the concentrations and chemical coherence between elements such as Cl-F-P2O5 and Ru-Os. The primitive lunar crust may be characterized by the type of feldspathic rocks which are enriched in trace elements, such as Cl, Br, U, Te, Ru, and Os, as found in 'rusty' rock 66095 and in 61016; other feldspathic rocks are depleted and may be of secondary origin.
The K, Rb, Sr, Ba and rare-earth-element contents of some Archean volcanic rocks from the Vermilion greenstone belt, northeast Minnesota, were determined by the isotopic dilution method. The characteristics of trace element abundances, supported by the field occurrences and major element chemistry, suggest that these volcanic rocks were formed in an ancient island arc system.
A correlation interferometer has been developed for the measurement of carbon monoxide and methane at 2.35 micrometers in the troposphere and in the stratosphere. This instrument has been tested in laboratory tests, solar-looking outdoor tests, and downward-looking airplane-based tests. The aircraft tests were flown on a Falcon fanjet provided by The Canada Centre for Remote Sensing over both polluted and unpolluted regions of North America. The results of these various tests are discussed. Based on the results obtained for carbon monoxide and methane, a study was undertaken to investigate the feasibility of measuring other atmospheric trace species by correlation interferometry. Results of the feasibility study for carbon dioxide, water vapor, ammonia, nitrous oxide, nitric oxide, nitrogen dioxide, sulfur dioxide, and several hydrocarbons are presented.
The Allende samples analyzed include seven Ca, Al-rich aggregates, ten melilite chondrules, an olivine chondrule, and two olivine-rich aggregates. The Allende meteorite has been described as a type III carbonaceous chondrite. Major element abundances were determined with the electron microprobe technique reported by Reed and Ware (1972). An MS7 spark source mass spectrometer was used for the determination of trace element abundances.
Rare gas data are presented from step-wise heatings of lunar breccias 14066 and 14318 and from an interlaboratory cross-calibration of five standards used in Ar-40/Ar-39 dating. While different in detail, the Ar release patterns in the four samples yield indistinguishable plateau ages of 3.93 plus or minus 0.03 b.y. and above 400 C total ages of 3.87 plus or minus 0.06 b.y. Concentrations of K, Ca, Ba, Br, U and I are given for 14318 and 14066. We also present an updating of all of the Ar-40/Ar-39 ages and trace element concentrations previously published by this laboratory.
Preliminary review of a study of trace elements and compound concentrations in the ambient suspended particulate matter in Cleveland, Ohio, measured from August 1971 through June 1973, as a function of source, monitoring location, and meteorological conditions. The study is aimed at the development of techniques for identifying specific pollution sources which could be integrated into a practical system readily usable by an enforcement agency.
An experimental method for determinating the flow tracing fidelity of a scattering aerosol used in laser Doppler velocimeters was developed with particular reference to the subsonic turbulence measurements. The method employs the measurement of the dynamic response of a flow seeding aerosol excited by acoustic waves. The amplitude and frequency of excitation were controlled to simulate the corresponding values of fluid turbulence components. Experimental results are presented on the dynamic response of aerosols over the size range from 0.1 to 2.0 microns in diameter and over the frequency range 100 Hz to 100 kHz. It was observed that unit density spherical scatterers with diameters of 0.2 microns followed subsonic air turbulence frequency components up to 100 kHz with 98 percent fidelity.
The sensitivity and reliability of neutron activation analysis in detecting trace elements in solid rocket effluents are discussed. Special attention was given to Al and Si contaminants. The construction and performance of a thermal column irradiation unit was reported.
A description and operating instructions for the Analysis Program Arizona Radiation Trace (APART) are given. This is a computer program that is able to efficiently and accurately predict the off-axis rejection characteristics of unwanted stray radiation for complex rotationally symmetric optical systems. The program first determines the critical objects or areas that scatter radiation to the image plane either directly or through imaging elements: this provides the opportunity to modify, if necessary, the design so that the number of critical areas seen by the image plane is reduced or the radiation to these critical areas is minimized. Next, the power distribution reaching the image plane and a sectional power map of all internal surfaces are computed. Angular information is also provided that relates the angle by which the radiation came into a surface to the angle by which the radiation is scattered out of the surface.
Radio wave propagation predictions are described in which modern comprehensive theoretical ionospheric models are coupled with ray-tracing programs. In the computer code described, a network of electron density and collision frequency parameters along a band about the great circle path is calculated by specifying the transmitter and receiver geographic coordinates, time, the day number, and the 2800-MHz solar flux. The ray paths are calculated on specifying the frequency, mode, range of elevation angles, and range of azimuth angles from the great circle direction. The current program uses a combination of the Penn State MKI E and F region models and the Mitra-Rowe D and E region model. Application of the technique to the prediction of satellite to ground propagation and calculation of oblique incidence propagation paths and absorption are described. The implications of the study to the development of the next generation of ionospheric models are discussed.
Measurements are given for sixteen trace elements determined by radiochemical neutron activation analysis in six samples of four components of lunar rock 14321, 184. The samples were of basalt (1B), matrix (9A), microbreccia-2 (15), and microbreccia-3 (14A, 16A, and 19A) components. The ancient meteoritic components in the samples were determined according to the ratios of siderophile elements (Ir/Au and Ge/Au) found in the samples.