Cultivating Mars: A Project-Based Learning Lab Analyzing an Oxygen Based Redox Reaction in Order to Design an Oxygen-Rich Environment on the Red Planet.

In a series of activities/labs, designed in a building block approach, whereas each subsequent lab builds into the next, students will explore the reactivity and production of oxygen in various biological and chemical systems. Through student-constructed analyses, participants will optimize oxygen-generating systems for the colonization of Mars, wherein their system will be used as part of a narrative to construct a livable habitat for future astronauts. Use of remote access technology to a Scanning Electron Microscope (SEM) with elemental analysis capabilities allows students to investigate their oxygen reaction via formation of iron oxide, resulting in rich multidimensional and contextualized scientific exploration in the chemistry classroom.

Frequency dependent steering with backward leaky waves via photonic crystal interface layer.

A Photonic Crystal (PC) with a surface defect layer (made of dimers) is studied in the microwave regime. The dispersion diagram is obtained with the Plane Wave Expansion Method. The dispersion diagram reveals that the dimer-layer supports a surface mode with negative slope. Two facts are noted: First, a guided (bounded) wave is present, propagating along the surface of the dimer-layer. Second, above the light line, the fast traveling mode couple to the propagating spectra and as a result a directive (narrow beam) radiation with backward characteristics is observed and measured. In this leaky mode regime, symmetrical radiation patterns with respect to the normal to the PC surface are attained. Beam steering is observed and measured in a 70 degrees angular range when frequency ranges in the 11.88-13.69 GHz interval. Thus, a PC based surface wave structure that acts as a frequency dependent leaky wave antenna is presented. Angular radiation pattern measurements are in agreement with those obtained via numerical simulations that employ the Finite Difference Time Domain Method (FDTD). Finally, the backward radiation characteristics that in turn suggest the existence of a backward leaky mode in the dimer-layer are experimentally verified using a halved dimer-layer structure.