Enhanced Organic Nitrate Formation from Peroxy Radicals in the Condensed Phase.

Organic alkoxy (RO) and peroxy (RO) radicals are key intermediates in multiphase atmospheric oxidation chemistry, though most of the study of their chemistry has focused on the gas phase. To better understand how radical chemistry may vary across different phases, we examine the chemistry of a model system, the 1-pentoxy radical, in three phases: the aqueous phase, the condensed organic phase, and the gas phase. In each phase, we generate the 1-pentoxy radical from the photolysis of -pentyl nitrite, run the chemistry under conditions in which RO radicals react with NO, and detect the products in real time using an ammonium chemical ionization mass spectrometer (NH CIMS).

Indoor Air Quality Implications of Germicidal 222 nm Light.

One strategy for mitigating the indoor transmission of airborne pathogens, including the SARS-CoV-2 virus, is irradiation by germicidal UV light (GUV). A particularly promising approach is 222 nm light from KrCl excimer lamps (GUV); this inactivates airborne pathogens and is thought to be relatively safe for human skin and eye exposure. However, the impact of GUV on the composition of indoor air has received little experimental study.

Emergent microrobotic oscillators via asymmetry-induced order.

Spontaneous oscillations on the order of several hertz are the drivers of many crucial processes in nature. From bacterial swimming to mammal gaits, converting static energy inputs into slowly oscillating power is key to the autonomy of organisms across scales. However, the fabrication of slow micrometre-scale oscillators remains a major roadblock towards fully-autonomous microrobots.

Autoperforation of two-dimensional materials to generate colloidal state machines capable of locomotion.

A central ambition of the robotics field has been to increasingly miniaturize such systems, with perhaps the ultimate achievement being the synthetic microbe or cell sized machine. To this end, we have introduced and demonstrated prototypes of what we call colloidal state machines (CSMs) as particulate devices capable of integrating sensing, memory, and energy harvesting as well as other functions onto a single particle. One technique that we have introduced for creating CSMs based on 2D materials such as graphene or monolayer MoS is "autoperforation", where the nanometer-scale film is fractured around a designed strain field to produce structured particles upon liftoff.