CPM Seminar

In analytical chemistry and physics thermal gravimetric (TG) analysis is routinely used to study mass variation owing to desorption, adsorption or decomposition of materials. We have developed a new micromechanical thermogravimetric (MMTG) method based on a cantilever-type microbalance to heat and weigh nanogram sample uantities with picogram mass resolution. The resonance frequency of a piezoresistive cantilever is detected. Such sensors typically used for scanning force microscopy, can execute a defined temperature program by controlling the electrical power dissipated in the micromechanical device. The mechanical properties as well as the heating and temperature distribution of such a sensor are simulated by finite element (FE) calculations. These simulations allow the sensor to be calibrated accurately for detailed quantitative data analysis. Additionally we present new measurements of individual single zeolite crystals (ZSM-5) as well as FE simulations of this miniaturized chemical analytical system.

Monday, October 26th 1998, 15:30
Ernest Rutherford Physics Building, room 118