Making measurements is the heart of science. Long-term, ongoing studies concern measuring heat transport properties, specifically thermal diffusivity, and spectroscopic measurements from the ultraviolet to the far-infrared. The particular combination of modern instruments is unique, and applies to how matter interacts with energy.
Major Instrumentation
Two Laser-flash Apparati
Anne Hofmeister is loading a sample in the LFA 427 manufactured by Netzsch, for high-temperature laser-flash analysis. Anne placed the sample on an aperture using a pair of tweezers. The furnace (silver colored cylinder above) with be lowered over the sample. A high-power infrared laser provides a heat pulse from below, and sample emissions are recorded as a function of time. Time-temperature curves are shown on the bulletin board. This method provides thermal diffusivity from Fourier’s equation that is accurate to 2-3% whereas achieving 5% is difficult with other modern methods while historic methods have large systematic errors. The laboratory has published over 30 papers with data on minerals and rocks, plus a book, leading to a new picture of heat transport in Earth materials. Here is a view of the closed furnace (silver-colored), the laser is below and the detector is the grey cylinder above. The cabinet on the left contains the power source for the laser.New! LFA-467 manufactured by Netzsch can accurately and simultaneously gather data simultaneously on heat capacity and thermal diffusivity from 173 to 773 K, permitting accurate calculation of thermal conductivity over this temperature range. The large cylinder to the left provides liquid nitrogen coolant to reach low temperatures.
Push-rod Dilatometer
Push-rod dilatometer in the lab. This is a Netzch DIL 402c, with low and high temperature furnaces that measures alpha to ±1% from -150 to 2000°C and collects data continuously with T, permitting kinetic studies.
Inside the push-rod dilatometer. The white rod is the thermocouple. The thin grey rod pushes on the sample, here a large grey cylinder with MORB glass inside.
