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Applications of surface and physico-chemical techniques to the clinical setting, in particular related to the urogenital tract, have been sporadic, often concentrating on aspects of biocompatibility and interactions of blood cells with materials. In an era where billions of such devices are implanted annually, it is important to utilize such techniques to improve our understanding of material-host interactions. In an effort to encourage further such interactive investigations, this review will illustrate some practical biomedical examples where utilization of sophisticated surface-science techniques has provided valuable insight into interfacial events between host components, micro-organisms and material surfaces. Techniques to reduce bacterial infection and encrustations will be discussed, and suggestions given for future lines of enquiry. © 1995.

VESPERS beamline is a hard X-ray microprobe beamline dedicated to micro-diffraction and micro-fluorescence analysis at the Canadian Light Source; it requires multi-bandpass X-ray beams for different types of samples and experiments. A specially designed double crystal/multilayer monochromator was built for this purpose with three different bandpasses: 0.01%, 1.6% and 10%. The diffraction elements used for the monochromator have a triple-stripe design using Si(111) crystal as a single substrate with two differing stripes of Mo/B4C multilayers deposited thereon. The uncovered Si(111) section provides a 0.01% bandpass, while the periodic and depth-graded Mo/B4C multilayers provide 1.6% and 10% bandpasses, respectively. This paper outlines the requirements and specifications of the diffracting elements as well as the design, deposition and optimization of the multilayers. The performance of the deposited multilayer structures has been tested using Cu-Kα radiation line with a Huber diffractometer.

Substrates of aluminium alloy 2011 were plasma nitrided using an inductively coupled plasma source and characterised in situ using X-ray photoelectron spectroscopy (XPS). The maximum entropy method (MEM), used for sharpening the spectra, has enabled the identification of metallic Al and AlN at binding energies of 72.7 and 74.4 eV, respectively. Other peaks at 73.4, 75.0, 75.5 and 76.2 eV are ascribed to Al oxide species. Nitriding carried out for 3 h at 300 and 400 °C gave rise to a higher relative surface AlN concentrations compared to treatments carried out at lower temperatures or for shorter times. Oxidation of the substrate surface rather than nitriding occurred if the substrate surfaces were treated for shorter times at high temperatures. The substrates were also characterised ex situ by dynamic time-of-flight secondary ion mass spectroscopy (ToF-SIMS) and scanning electron microscopy. AlN layers were found to extend up to 15 nm into the metal. A large number of CuAl 2 precipitants are formed on the grain faces as well as on the grain boundaries after treatment at 400 °C. Faster cooling rates after the nitriding process and/or lower nitriding temperatures are required to prevent segregation of the precipitants at the grain boundaries. After exposure to air, further oxidation occurs and the thickness of the surface oxide layer increases.