The Nascent Specter: Vision, Corporeality, Reproduction, and Modernity in Henry James and Photographic Theory

Honors (Bachelor's)EnglishUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/107800/1/rzaluzec.pd

Ion irradiation of the TiO2 polymorphs and cassiterite.

Thin crystals of rutile, brookite, anatase, and cassiterite were irradiated in situ in the transmission electron microscope using 1.0 MeV Kr ions at 50–300 K. Synthetic rutile and natural cassiterite, with 0.1–0.2 wt% impurities, remain crystalline up to a fluence of 5 x 1015 ions cm–2 without evidence for amorphization at 50 K. Natural brookite and anatase, with 0.3–0.5 wt% impurities, become amorphous at fluences of 8.1 x 1014 and 2.3 x 1014 ions cm–2, respectively. We have also studied two natural rutile samples containing ~1.7 and 1.2 wt% impurities. These samples became amorphous at 9.2 x 1014 and 8.6 x 1014 ions cm–2 at 50 K, respectively. Further analyses of the fluence-temperature data for natural brookite, rutile, and anatase give critical amorphization temperatures of 168 ± 11, 209 ± 8, and 242 ± 6 K, respectively. Results are briefly discussed with respect to several criteria for radiation resistance, including aspects of the structure, bonding, and energetics of defect formation and migration. © 2010, Mineralogical Society of Americ

Lithium Ion Battery Materials as Tunable, Redox Non-Innocent Catalyst Supports

The development of general strategies for the electronic tuning of a catalyst’s active site is an ongoing challenge in heterogeneous catalysis. To this end, herein we describe the application of Li-ion battery cathode and anode materials as redox non-innocent catalyst supports that can be continuously modulated as a function of lithium intercalation. A zero-valent nickel complex was oxidatively grafted onto the surface of lithium manganese oxide (LixMn2O4) to yield isolated Ni(II) occupying the vacant interstitial octahedral site in the Li diffusion channel on the surface and subsurface of the spinel structure (Ni/LixMn2O4). The activity of Ni/LixMn2O4 for olefin hydrogenation, as a representative probe reaction, was found to increase monotonically as a function of support reductive lithiation. Simulation of Ni/LixMn2O4 reveals the dramatic impact of surface redox states on the viability of the homolytic oxidative addition mechanism for H2 activation. Catalyst control through support lithiation was extended to an organotantalum complex on LixTiO2, demonstrating the generality of this phenomenon