The morphology of micelles formed by two novel metallosurfactants has been studied by small-angle neutron scattering (SANS) and small-angle-X-ray scattering (SAXS). The two surfactants both contain a dodecyl chain as the hydrophobic moiety, but differ in the structure of the head group. The surfactants are Cu(II) complexes of monopendant alcohol derivatives of a) the face-capping macrocycle 1,4,7-triazacyclanonane (tacn), and b) an analogue based upon the tetraazamacrocycle 1,4,7,10-tetraazacyclododecane. Here, neutron scattering has been used to study the overall size and shape of the surfactant micelles, in conjunction with X-ray scattering to locate the metal ions. For the 1,4,7,10-tetraazacyclododecane-based surfactant, oblate micelles are observed, which are smaller to the prolate micelles formed by the 1,4,7-triazacyclononane analogue. The X-ray scattering analysis shows that the metal ions are distributed throughout the polar head-group region, rather than at a well-defined radius; this is in good agreement with the SANS-derived dimensions of the micelle. Indeed, the same model for micelle morphology can be used to fit both the SANS and SAXS data.

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Direct measurement of the spectral distribution emitted by an x‐ray tube with a solid‐state detector is described. Spectral distributions of various x‐ray tubes differing in anode material were measured and compared. Numerical values and relevant data for Cu, Mo and W x‐ray tubes are presented.

A knowledge of the spectral distribution method emitted by an x-ray tube is important for all calculations in quantitative x-ray fluorescence analysis. A simple way of directly measuring the primary spectrum of an x-ray tube with a solid-state detector is presented. For samples which meet thin-film criteria sensitivity factors based on the measured primary spectrum were calculated and compared with experimental values.

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A method for measuring spectral distributions of x-ray tubes directly with a solid-state detector is presented. Different anode materials (chromium, molybdenum, rhodium and tungsten) have been measured. Results for various applied voltages and take-off angles have been obtained.