Photodissociation of O3 in the Hartley Band. Reactions of O(1D) and O2(1Σg+) with O3 and O2

Exploring the working mechanism of graphene patterning by magnetic-assisted UV ozonation

When assisted with an inhomogenous vertical magnetic field, ultraviolet (UV) ozonation turns directional and is testified to be applicable to graphene patterning. Using a more cost-effective low-pressure mercury lamp, we further explore the underlying working mechanism by changing oxygen content, introducing reactive ozone or inert nitrogen molecules, and study the lateral under-oxidation impeded Dirac point shifts for a graphene field-effect transistor under UV irradiation. The paramagnetic oxygen molecule X³Σ accelerates toward graphene with the magnetic moment aligned parallel to the magnetic field. The O(³P) atoms, stemming from such a directional oxygen molecule, have a high initial velocity before being further accelerated, and therefore enhance the oxidation capability compared with those from weak diamagnetic ozone molecules. Intermolecular or atomic-molecular collisions between the high-speed oxygen molecules/atoms and the randomly moved weak diamagnetic molecules, including nitrogen and ozone, appear crucial in deteriorating graphene patterning by increasing the lateral under-oxidation. This study may shed light on our understanding of graphene patterning by magnetic-assisted UV ozonation.

Possible high energy laser at 1.27 microm

Preliminary theoretical and experimental evidence is presented that suggests the potential of lasing from the strongly forbidden O(2)((1)Delta(g)) ? C(2)((3)Sigma (-)(g)) transition of molecular oxygen. A rate equation model is developed which predicts pulse energies up to several hundred joules/liter atmosphere for typical mixtures of 10(3):2N(2) activated by uv photolysis in less than 10 microsec. Preliminary results from a flash photolysis laser apparatus demonstrating 1.27-microm lasing are presented. Results from a computer analysis assessing the possibility of using this system as a multipass amplifier are also given.