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Neutron activation analysis is used for quantitative identification of trace metals in copper. Establishing a unique fingerprint of impurities in Michigan copper would enable identification of artifacts made from this copper.
Computerized information storage and display system directs storage of documents, drawings, photographs, fingerprints, etc., and permits rapid retrieval for real-time viewing on remote consoles.
Study of C-13 nuclear magnetic resonance (NMR) spectra of polycyclic fused systems. The fingerprint qualities of the natural abundance in C-13 NMR spectra permitting unequivocal identification of these compounds is discussed. The principle of structural additivity of C-13 NMR information is exemplified on alpha and beta androstanes, alpha and beta cholestanes, ergostanes, sitostanes, and isodecanes.
Window surface is laid flat on top of photosensitive paper. Opposite side of glass is covered by black cloth. Window edges are then illuminated by light flash through fiber optics. Exposed paper is processed and inspected. Paper shows scratches, bubbles, dust particles, and fingerprints on glass surface.
The author has identified the following significant results. A new device, called a Spectral Attenuation Board, has been designed and tested, which enables ERTS-1 sea truth collection teams to monitor the attenuation depths of three colors continuously, as the board is being towed behind a boat. The device consists of a 1.2 x 1.2 meter flat board held below the surface of the water at a fixed angle to the surface of the water. A camera mounted above the water takes photographs of the board. The resulting film image is analyzed by a micro-densitometer trace along the descending portion of the board. This yields information on the rate of attenuation of light penetrating the water column and the Secchi depth. Red and green stripes were painted on the white board to approximate band 4 and band 5 of the ERTS MSS so that information on the rate of light absorption by the water column of light in these regions of the visible spectrum could be concurrently measured. It was found that information from a red, green, and white stripe may serve to fingerprint the composition of the water mass. A number of these devices, when automated, could also be distributed over a large region to provide a cheap method of obtaining valuable satellite ground truth data at present time intervals.
Methods for metabolic fingerprinting of pathogenic oral bacteria were developed and the effects of Skylab missions on salivary electrolyte levels were studied. High resolution gas liquid chromatographic (GLC) and pyrolysis-GLC procedures were used to obtain metabolic profiles of closely related bacteria associated with dental caries and periodontal disease. It was found that the GLC procedures provide a practical and reproducible means of obtaining metabolic markers for identifying closely related strains of these organisms. Fractions of stimulated whole saliva samples from the prime and back-up crews of the three Skylab missions were used to measure salivary electrolyte concentrations. All the electrolytes previously reported as having increased in urine and feces during the missions were assessed. Sodium, potassium, calcium, magnesium, phosphorous and chloride were studied. A decrease in sodium and an increase in magnesium were observed, but the mineral imbalances attributable to the mission-related increases in urinary electrolytes were not detected.
The addition polyimide, LARC-160, which was originally synthesized from low cost liquid monomers as a laminating resin in ethanol, was prepared as a solventless, high viscosity, neat liquid resin. The resin was processed by hot-melt coating techniques into graphite prepreg with excellent tack and drape. Comparable data on graphite reinforced laminates made from solvent-coated and various hot-melt coated prepreg were generated. LARC-160, because of its liquid nature, can be easily autoclave processed to produce low void laminates. Liquid chromatographic fingerprints indicate good reaction control on resin scale ups. Minor changes in monomer ratios were also made to improve the thermal aging performance of graphite laminates.
The problem of designing analytical failure-detection systems (FDS) for sensors and actuators, using observers, is addressed. The use of observers in FDS is related to the examination of the n-dimensional observer error vector which carries the necessary information on possible failures. The problem is that in practical systems, in which only some of the components of the state vector are measured, one has access only to the m-dimensional observer-output error vector, with m or = to n. In order to cope with these cases, a secondary observer is synthesized to reconstruct the entire observer-error vector from the observer output error vector. This approach leads toward the design of highly sensitive and reliable FDS, with the possibility of obtaining a unique fingerprint for every possible failure. In order to keep the observer's (or Kalman filter) false-alarm rate under a certain specified value, it is necessary to have an acceptable matching between the observer (or Kalman filter) models and the system parameters. A previously developed adaptive observer algorithm is used to maintain the desired system-observer model matching, despite initial mismatching or system parameter variations. Conditions for convergence for the adaptive process are obtained, leading to a simple adaptive law (algorithm) with the possibility of an a priori choice of fixed adaptive gains. Simulation results show good tracking performance with small observer output errors, while accurate and fast parameter identification, in both deterministic and stochastic cases, is obtained.
Graphs show preflight and postflight reflectivities in percent for exposed and covered mirrors carried on the OSS-1 payload pallet during STS-3. No changes greater than 1.8 sigma were observed except for a fingerprint. Weak evidence for degradation at 1216 A and 1600 A was found in several samples. There was no difference between flight mirrors and control mirrors. Covered samples suffered more than samples exposed to the Sun, but the differences are barely significant. The exposed side of the flight mirrors were somewhat dusty. No evidence was found for permanent solar-induced or shuttle-induced deterioration. There also was no evidence on oil-pumped vacuum versus oil-free vacuum during coating.
Techniques for determining the composition of small dust grains in interstellar matter are discussed. The best way to study the composition of interstellar grain mantles is by infrared spectroscopy. The absorption features in a complete infrared spectrum from 2 to 15 microns can be used as fingerprints to identify the absorbing molecule. Ground-based observations around 3 microns confirmed the presence of H2O ice in interstellar grain mantles, through the detection of the 3.08 micron OH stretching vibration. The detection of other molecules, in particular the carbon bearing molecules, is however hampered by atmospheric absorption in the 5-8 micron region and the presence of the strong ice and silicate bands, which dominate the 3 and 10 micron region respectively. Kuiper Airborne Observatory observations of the 5-8 micron region of the spectrum are therefore extremely important to determine the composition of interstellar grain mantles. The 5 to 8 micron spectra of molecular cloud sources was obtained using a 24 detector grating spectrometer. An important characteristic of this spectrometer is that the whole spectrum is obtained simultaneously. It is therefore relatively easy to correct for atmospheric transmission.
In order to define ribonuclease contamination, an assay for ribonuclease having picogram level sensitivity was established. In this assay, polycytidylic acid is digested by ribonuclease leading to smaller fragments of poly C that remain soluble after treatment of the sample with perchloric acid and lanthanum acetate. An absorbance measurement at 260 nm of the supernatant from the centrifuged sample measures the ribonuclease. A standard curve is shown. Using this assay procedure, ribonuclease contamination was found to be significant in routine laboratory proteins, in particular, bovine serum albumin, lysozyme, catalase, and cytochrome C. This was confirmed by demonstrating a considerable reduction in this activity in the presence of phosphate buffer since phosphate inhibits ribonuclease. Ribonuclease contamination was not significantly encountered in routine laboratory glassware, plasticware, column surfaces, chromatographic particles, and buffer reagents, including airborne contamination. Some contamination could be introduced by fingerprints, however.
The compilation of ultra high energy jets suggests at present the existence of a bump in primary energy spectrum (with the standard concept of high energy collisions). The pseudo-rapidity distribution exhibits some typical anomalies, more than the (P sub t) behavior, which are (may be) the fingerprints of quark gluon plasma transition. The next results of Emulsion Chamber on Supersonic (ECHOS) will be in both cases determinant to confirm those tendancies, as well as an important effort of the cosmic ray community to develop in that sense a flying emulsion chamber experiment.
The introduction of time resolved observations can provide a very penetrating tool in the practice of laser fluorosensing. The investigations have demonstrated a relevance of multispectral, time resolved analysis for oil fingerprinting. By comparative studies on a variety of crude oils and their most significant fractions, it was found that the process of time decay in a composite oil is characterized by a few steps, which are associated with specific components in the medium light range. The average decay times of these pure fractions are markedly differentiated as to absolute values and spectral spread; as a consequence, the corresponding parameters in the resultant crude are quite sensitive to the particular mixture of these components. Measurements of the time response give then a finer discrimination between oil classes, depending on the relative content of certain fractions. Experiments were pursued with an improved fluorosensor facility, in order to test the application of time resolved fluorosensing to remote samples on water.
A small CO2 snow cleaning apparatus to clean both molecular films and particles from small and large components and surfaces was constructed. Various types of surfaces were cleaned using the CO2 technique. Vacuum deposited and sputtered metallic coatings such as germanium, aluminum, and silver and silicon wafers, and polished copper conical mirrors were purposely contaminated with everyday aerospace contaminants, including particle fallout and fingerprints. Precleaning characterization by Bidirectional Reflectance Distribution Function (BRDF), ellipsometry, nonvolatile residue, and microscopic particle evaluation served as evaluation of cleaning efficiency. Good results were obtained in trial application.
The granulite uncertainty principle, which states that it is difficult or impossible to determine with certainty the maximum geopressure and geotemperature that a granulite has experienced, is addressed. Also, geochemical fingerprinting cannot always be used reliably in the nebulous region that is transitional between metamorphic and igneous environments. Ion exchange thermometers are typically useful to approximately 800 C in slowly cooled plutonic rocks unless one uses a reintegration technique on unmixed minerals, or unless a metastable mineral assemblage can be observed. It is argued that in most granulites, fossil temperatures are typically obliterated by reequilibration and/or deformation during slow cooling. Granulite metamorphism may be further complicated by the common association with igneous activity. The previously-used geochemical indicators such as high K/Rb ratios and LIL depletion may not be strictly the result of granulite facies metamorphic depletion, but also may result from igneous processes, which depend on bulk and mineral compositions and on the mineralogy of the protolith. Detailed geologic mapping will be the ultimate arbitrator of whether a given geochemical signature is the result of igneous or metamorphic processes.
Molecular contamination of bonding surfaces can drastically affect the bond strength that can be achieved and therefore the structural integrity and reliability of the bonded part. The presence of thin contaminant films on bonding surfaces can result from inadequate or incomplete cleaning methods, from oxide growth during the time between cleaning (such as grit blasting) and bonding, or from failure to properly protect cleaned surfaces from oils, greases, fingerprints, release agents, or deposition of facility airborne molecules generated by adjacent manufacturing or processing operations. Required cleanliness levels for desired bond performance can be determined by testing to correlate bond strength with contaminant type and quantity, thereby establishing the degree of contamination that can be tolerated based on the strength that is needed. Once the maximum acceptable contaminant level is defined, a method is needed to quantitatively measure the contaminant level on the bonding surface prior to bonding to verify that the surface meets the established cleanliness requirement. A photoelectron emission technique for the nondestructive inspection of various bonding surfaces, both metallic and nonmetallic, to provide quantitative data on residual contaminant levels is described. The technique can be used to scan surfaces at speeds of at least 30 ft/min using a servo system to maintain required sensor to surface spacing. The fundamental operation of the photoelectron emission sensor system is explained and the automated scanning system and computer data acquisition hardware and software are described.
Morphological and spectrophotometric investigations have been extensively applied in the past years to various kinds of micron and/or submicron-sized grains formed by materials which are candidate to be present in space. The samples are produced in the laboratory and then characterized in their physio-chemical properties. Some of the most recent results obtained on various kinds of carbonaceous materials are reported. Main attention is devoted to spectroscopic results in the VUV and IR wavelength ranges, where many of the analyzed samples show typical fingerprints which can be identified also in astrophysical and cometary materials. The laboratory methodologies used so far are also critically discussed in order to point out capabilities and present limitations, in the view of possible application to returned comet samples. Suggestions are given to develop new techniques which should overcome some of the problems faced in the manipulation and analysis of micron solid samples.
The mid-IR spectral region of molecular clouds is known to show the fingerprints of molecules frozen in the icy mantles of the interstellar grains. To study the complex chemical and physical interactions on the ice mantles accreted on grains in molecular clouds numerous UV irradiation and diffusion experiments were performed. The irradiation of binary ices was studied. Using isotopic labelling on NH3/CO and NH3/O2 ices numerous compounds were identified, of which OCN(-), NO2(-), NO3(-), and NH4(+) ions reveal a new type of chemical reactions. It appeared that these compounds were formed by proton transfer reactions induced by the interaction between an acid (HNCO, HNO2, HNO3) and a base (NH3) through a hydrogen bond. This mechanism was confirmed by a study of photolyzed diluted argon mixtures. The main astrophysically relevant data from the overall study are presented. The 4.62 micron band in W33A can be reproduced with NH3/CO containing irradiated ices and was identified with OCN(-). The 6.87 micron band in W33A and other photostellar objects is reproduced with NH3/O2 containing ices and is identified with NH4(+).