Seminar: 12.7.11 / CREOL A214 / 11-12pm / Seminar: “Making Use Of Molecular Bands In LIBS Spectra In Recent Applications At NILES, Cairo University”,

Seminar: “Making Use Of Molecular Bands In LIBS Spectra In Recent Applications At NILES, Cairo University”, Mohamed Abdel Harith

CREOL A214

Wednesday, December 7, 2011 / 11-12pm

Mohamed Abdel Harith

Abstract:

Two recent research works conducted by the applied laser spectroscopy group (ALS) at NILES will be presented. Though the two works are in two different fields (one is an industrial application while the other is in Cultural heritage) but in both we have made use of the molecular bands in the obtained LIBS spectra.

The first work it has been focused on studying evolution of the cyanide (CN) and carbon (C₂) molecular spectral emission lines in the laser induced breakdown spectra of lubricating oil as a function of its consumption. The intensities of these molecular bands have been taken as indicator of engine oil degradation at certain mileage. The results proved that it is possible to have a direct, straightforward and easy method for prediction of lubricating oil degree of consumption. This may facilitate scheduling the proper time and/or mileage intervals for changing the oil to avoid any possibility of engine failure.

In the second work human calcified tissue samples of recent and archeological bones have been studied via the LIBS technique. The old samples were from three different ancient Egyptian dynasties. Elements normally used to study dietary habits (Sr, Ba, Al, and Pb) were analyzed and the interferences of postmortem or diagenic effects due to the burial place were investigated via LIBS analysis of soil samples taken from the same locations where the archeological bones have been buried. Study of CN and C₂ molecular bands in the obtained LIBS spectra of the bones revealed that these bands have strong intensities in recent bones spectra contrary to the archaeological ones. This is attributed to the degradation of the tissues and has been confirmed by following up calcium to phosphorus ratios in different bone samples.

For More Information:

Dr. Matthieu Baudelet

Senior Research Scientist

Townes Laser Institute, CREOL, UCF

Phone: 407-823-6910