Topic: absorption

Melissa and Jam examine how erasers remove graphite from paper. The episode connects the structure of graphite with the polymers and physical interactions that let an eraser lift a mark, contrasting absorption and adsorption and discussing what makes an everyday material effective for this purpose.

Spatial frequency domain imaging (SFDI) is a diffuse optical measurement technique that can quantify tissue optical absorption and reduced scattering on a pixel by-pixel basis. Measurements of absorption at different wavelengths enable the extraction of molar concentrations of tissue chromophores over a wide field, providing a noncontact and label-free means to assess tissue viability, oxygenation, microarchitecture, and molecular content. In this talk, I will describe openSFDI, an open-source guide for building a low-cost, small-footprint, multi-wavelength SFDI system capable of quantifying a