Measurement of edge residual stresses in glass by the phase-shifting method

Control and measurement of residual stress in glass is of great importance in the industrial field. Since glass is a birefringent material, the residual stress analysis is based mainly on the photoelastic method. This paper considers two methods of automated analysis of membrane residual stress in glass sheets, based on the phase-shifting concept in monochromatic light. In particular these methods are the automated versions of goniometric compensation methods of Tardy and Sénarmont. The proposed methods can effectively replace manual methods of compensation (goniometric compensation of Tardy and Sénarmont, Babinet and Babinet-Soleil compensators) provided by current standards on the analysis of residual stresses in glasses.     

Computer aided photoelasticity by an optimum phase stepping method

In this paper an automated photoelastic method based on the phase stepping technique is described. It provides full-field maps of the isoclinic parameter and the relative retardation. The technique is based on processing six images of a photoelastic specimen acquired using plane and circularly polarized light. The number of acquisitions and the type of polariscope used in this approach have been chosen with the aim at reducing the influence of quarter wave plate errors and obtaining raw photoelastic data in a periodic form suitable for easy applications of automatic unwrapping routines.     

A simple nebulization reflux system for use in ICP-AES

A simple and inexpensive recycling nebulizer for inductively-coupled plasma atomic emission spectrometry has been devised by slightly and reversibly modifying a conventional external pneumatic nebulizer. Its performance was checked with a number of analytes (Ca, Cu, Mg, P, Pt) in aqueous and serum solutions. Results show that the system is entirely reliable provided that argon carrier gas is presaturated with water vapor. The use of a peristaltic pump even in the recirculating version was found to be essential for a proper functioning if complex media are investigated.     

Measurement of antiproton lifetime using the ice storage ring

Antiprotons have been stored in the ICE Storage Ring and held for 85h with the help of stochastic cooling. We set a limit of at least 32 h for the antiproton lifetime (in its rest frame).     

Determination of ultra-trace levels of gold in size-segregated atmospheric particulate samples by laser induced fluorescence: towards an aerosol tracer

A method is described for measuring the gold content of integral and size-segregated samples of atmospheric particulate matter. After acid digestion and a liquid/ liquid extraction, the sample are analysed by Two-Colour Laser Induced Fluorescence in a graphite furnace. An absolute instrumental detection limit of 1 fg is achieved. Assuming a sampled volume of 1 m³, this corresponds to an atmospheric concentration of 50 fg m^–3. Due to blank limited noise, the above limits increase to 20 fg and 1 pg m^–3, respectively. Results of the analysis of filter samples as well as of size-segregated impactor samples are presented.     

Determination of ultra-trace levels of gold in size-segregated atmospheric particulate samples by laser induced fluorescence: towards an aerosol tracer

A method is described for measuring the gold content of integral and size-segregated samples of atmospheric particulate matter. After acid digestion and a liquid/ liquid extraction, the sample are analysed by Two-Colour Laser Induced Fluorescence in a graphite furnace. An absolute instrumental detection limit of 1 fg is achieved. Assuming a sampled volume of 1 m(3), this corresponds to an atmospheric concentration of 50 fg m(-3). Due to blank limited noise, the above limits increase to 20 fg and 1 pg m(-3), respectively. Results of the analysis of filter samples as well as of size-segregated impactor samples are presented.