Disappearance of the Boson Peak in Unfolded Enzyme Solutions and Development of Lightweight Electromagnetic Interference Shielding Material
Enzymes are essential to life in all organisms and maintain their role as the most efficient catalysts to date. However, we still do not fully understand the inner workings of enzymes that facilitates their functionality. One aspect of enzymes, and all proteins, that gives insight into their function, is their vibrational or phonon dynamics. Furthermore, one feature of the phonon dynamics that is said to be universal to proteins is the boson peak, an excess in the vibrational density of states in the range of about 2 meV to 4 meV. This work uses inelastic x-ray scattering (IXS) to measure the phonon dynamics on both folded and unfolded hen egg white lysozyme (HEWL) solutions. We measured both HEWL solutions at q points between 2 nm-1 and 5 nm-1. These measurements show the disappearance of the boson peak in the unfolded solution.Electromagnetic interference (EMI) is harmful for all kinds of electronic devices and may damage them or cause them to stop working entirely. This is important even on the Moon, where there is no atmospheric protection from any space radiation. This work studies the implementation of MXenes, an electrically conductive 2D class of materials, into polymer composites to create lightweight EMI shielding material suitable for power transmission cables on the Moon. Through dielectric spectroscopy measurements, we show that the incorporation of low weight percentages of MXene fillers in polymer composites can raise the EMI shielding effectiveness (SE) without greatly increasing its electrical conductivity.