PubMed Health⌕ Search

Biomedical subjects

M J French

Publications and source records attributed to M J French.

4 recordsLinked to original sources

The effects of welding parameters on ultra-violet light emissions, ozone and CrVI formation in MIG welding.

This paper describes the relationships between ultra-violet emission, ozone generation and CrVI production in MIG welding which were measured as a function of shield gas flow rate, welding voltage, electrode stick-out and shield gas composition using an automatic welding rig that permitted MIG welding under reproducible conditions. The experimental results are interpreted in terms of the physico-chemical processes occurring in the micro- and macro-environments of the arc as part of research into process modification to reduce occupational exposure to ozone and CrVI production rates in MIG welding. We believe the techniques described here, and in particular the use of what we have termed u.v.-ozone measurements, will prove useful in further study of ozone generation and CrVI formation and may be applied in the investigation of engineering control of occupational exposure in MIG and other welding process such as Manual Metal Arc (MMA) and Tungsten Inert Gas (TIG).

Air Pollutants, Occupational↗

Leaded windows as a source of lead within homes.

Corrosion of 'cames', i.e., the lead binding or decorative strips in leaded windows, is a significant, but previously unreported source of lead within older homes. Surfaces close to the leaded windows are highly contaminated with lead but the content of lead in dust diminishes rapidly within the first 2 m away from the window and is minimal after 3 m. The dust near the window was identified, using X-ray diffraction, as mainly composed of basic lead carbonate. Condensation water on leaded windows contains appreciable lead whereas for unleaded windows it is negligible. The exterior surface of unleaded windows contains more lead than the interior surface but the converse is true for leaded windows. A laboratory simulation suggested that corrosion by window condensate was likely to be the principal mechanism by which lead entered the home environment.

Dust↗

A study of collagen and gelatin solutions by optical self beat spectroscopy.

A study of the conformation of collagen and gelatin in aqueous solution by Optical Self Beat Spectroscopy is reported. The translational diffusion coefficient of monomeric tropocollagen was experimentally measured from the half-width of the Rayleigh scattered radiation and the value obtained is shown to be in good agreement with that calculated from hydrodynamical theory for the tropocollagen rod. The Self Beat Spectrometer was also used to investigate the factors affecting the aggregation and flexing of molecules in dilute gelatin solutions and the gel-sol transition in more concentrated gelatin solutions.

Animals↗