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Measuring the error introduced by the machine and human in a man-machine system is an important step in understanding and improving the system. Two experiments assessed the error from the total system in length measurements and shape classification. A separate analysis calculated the error introduce by the camera. The average error for length measurements was 2.33 pixels with a standard deviation of 2.399. The error in edge location introduce by the camera was 5-10 pixels. This indicates that humans generally are good at measuring lengths, but have difficulty near the threshold of resolution. Results from the classification task indicate that humans have lower then expected intra and inter geologist consistency. The study indicates that increasing the resolution of the camera system increases length measurement accuracy and that training may be the best way to improve classification consistency.

We have performed specific heat, resistivity, and magnetic measurements on a series of glassy aluminum alloys containing up to 93 at. % Al. In addition to the fact that we can extrapolate from our data the values of superconducting temperature (>5 K) and resistivity (approx.20 ..mu cap omega.. cm) for amorphous Al, our results also provide evidence that significant softening of phonon modes (in the case of glassy Al/sub 92/La/sub 8/, a drastic reduction is observed with a Debye temperature of approx.242 K as compared with approx.428 K in crystalline Al) is responsible for the enhanced superconductivity of up to 8.5 K observed in some metastable Al alloys. For glassy Al alloys containing a few at. % Gd, the maximum in specific heat is observed at more than twice the magnetic ordering temperature defined by the cusp in susceptibility, markedly different from that of canonical spin glasses. The structural differences between these glassy Al alloys and other magnetic alloys are pointed out. Ce in glassy Al shows a large valence instability, yielding an effective moment of 1.37..mu../sub B/ at room temperature to approx.0.25..mu../sub B/ at 5 K, which was not observed previously in an amorphous metal.

Resume Cinq patients sont atteints d'une infection a Pasteurella multocida . Cette infection survient apres morsure animale chez deux patients ; en l'absence de tout contact animal chez deux autres. Trois malades presentent une forme septicemique grave. L'evolution est favorable dans quatre cas sous traitement antibiotique.

We have investigated the transport and superconducting properties of the Mg/sub 32/(Al,Zn)/sub 49/-type icosahedral (I) and Frank-Kasper (FK) phases. All measurements were performed on single-phase samples. The I and FK phases of Al/sub 52.4/Cu/sub 12.6/Mg/sub 35/ are superconducting below 0.81 and 0.73 K, respectively. Their electronic densities of states at the Fermi energy were obtained from upper-critical-field measurements. The I phase has (1) a higher low-temperature (4.2 K) resistivity of approx. =58 ..mu cap omega.. cm compared with approx. =23 ..mu cap omega.. cm for the FK phase and (2) a lower renormalized density of states of approx. =0.52 states/eVXom versus approx. =0.89 states/eVXom for the FK phase. The results are discussed with respect to theoretical models. Fitting magnetoresistance data of the I phase to localization theory gives a spin-orbit scattering time of approx. =5 x 10/sup -12/ sec and an inelastic scattering time inversely proportional to T/sup 2/. The resistivities of the I and FK phases of Al/sub 20.2/Zn/sub 40.3/Mg/sub 39.5/ are also measured, and superconductivity is not detected down to approx. =0.3 K. The transport properties of these icosahedral quasicrystals are compared with other I-phase alloys containing d valence electrons.

An investigation of the equilibria formed between the terminal olefins 1-hexene and 1-octene and Na2Pd2Cl6 in glacial acetic acid, using preparative, Raman, and ultra-violet and visible spectroscopic methods has shown that the principal olefin complexes formed are Na[Pd2Cl5(Olefin)], at low olefin concentrations, and [Pd2Cl4(Olefin)2], at high olefin concentrations. The value is emphasised of using the Method of Continuous Variations (Job's Method) at as wide a range of wavelengths as possible for studying systems in which more than one metal—ligand complex is formed.

Use of 2-thiophene- trans -aldoxime as the precipitating agent provides an improved method for gravimetric determination of palladium.